Week 2 – CAST

“Mortality and Morbidity in Patients Receiving Encainide, Flecainide, or Placebo”

The Cardiac Arrhythmia Suppression Trial (CAST)

N Engl J Med. 1991 Mar 21;324(12):781-8. [full text]
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Ventricular arrhythmias are common following MI, and studies have demonstrated that PVCs and other arrhythmias such as non-sustained ventricular tachycardia (NSVT) are independent risk factors for cardiac mortality following MI. As such, by the late 1980s, many patients with PVCs post-MI were treated with antiarrhythmic drugs in an attempt to reduce mortality. The 1991 CAST trial sought to prove what predecessor trials had failed to prove – that suppression of such rhythms post-MI would improve survival.

This trial took post-MI patients with PVCs (with no sustained VT) and reduced EF and randomized them to an open-label titration period in which encainide, flecainide, or moricizine was titrated to suppress at least 80% of the PVCs and 90% of the runs of NSVT. Patients were then either randomized to continuation of the antiarrhythmic drug assigned during the titration period or transitioned to a placebo. The primary outcome was death or cardiac arrest with resuscitation, “either of which was due to arrhythmia.”

The trial was terminated early due to increased mortality in the encainide and flecainide treatment groups. 1498 patients were randomized following successful titration during the open-label period, and they were reported in this paper. The results of the moricizine arm were reported later in a different paper (CAST-II). The RR of death or cardiac arrest due to arrhythmia was 2.64 (95% CI 1.60–4.36; number needed to harm = 28.2). See Figure 1 on page 783 for a striking Kaplan-Meier curve. The RR of death or cardiac arrest due to all causes was 2.38 (95% CI 1.59–3.57; NNH = 20.6). Regarding other secondary outcomes, cardiac death/arrest due to any cardiac cause was similarly elevated in the treatment group, and there were no significant differences in non-lethal endpoints among the treatment and placebo arms.

In this large RCT, the treatment of asymptomatic ventricular arrhythmias with encainide and flecainide in patients with LV dysfunction following MI resulted in increased mortality. This study provides a classic example of how a treatment that seems to make intuitive sense based on observational data can be easily and definitively disproven with a placebo-controlled trial with hard endpoints (e.g. death). Although PVCs and NSVT are associated with cardiac death post-MI and reducing these arrhythmias might seem like an intuitive strategy for reducing death, correlation does not equal causation. Modern expert opinion at UpToDate notes no role for suppression of asymptomatic PVCs or NSVT in the peri-infarct period. Indeed such suppression may increase mortality. As noted on Wiki Journal Club, modern ACC/AHA guidelines “do not comment on the use of antiarrhythmic medications in ACS care.”

Further Reading/References:
1. CAST @ Wiki Journal Club
2. CAST @ 2 Minute Medicine
3. CAST-I Trial @ ClinicalTrials.gov
4. CAST-II trial publication, NEJM 1992
5. UpToDate “Clinical features and treatment of ventricular arrhythmias during acute myocardial infarction”

Summary by Duncan F. Moore, MD

Week 1 – CLOT

“Low-Molecular-Weight Heparin versus a Coumarin for the Prevention of Recurrent Venous Thromboembolism in Patients with Cancer”

by the Randomized Comparison of Low-Molecular-Weight Heparin versus Oral Anticoagulant Therapy for the Prevention of Recurrent Venous Thromboembolism in Patients with Cancer (CLOT) Investigators

N Engl J Med. 2003 Jul 10;349(2):146-53. [free full text]
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Malignancy is a pro-thrombotic state, and patients with cancer are at significant and sustained risk of venous thromboembolism (VTE) even when treated with warfarin. Warfarin is a suboptimal drug that requires careful monitoring, and its effective administration is challenging in the setting of cancer-associated difficulties with oral intake, end-organ dysfunction, and drug interactions. The 2003 CLOT trial was designed to evaluate whether treatment with low-molecular-weight heparin (LMWH) was superior to treatment with a vitamin K antagonist (VKA) in the prevention of recurrent VTE.

The study randomized adults with active cancer and newly diagnosed symptomatic DVT or PE to treatment with either dalteparin subQ daily (200 IU/kg daily x1 month, then 150 IU/kg daily x5 months) or a vitamin K antagonist x6 months (target INR 2.5, with 5-7 day LMWH bridge). The primary outcome was the recurrence of symptomatic DVT or PE within 6 months of follow-up. Secondary outcomes included major bleed, any bleeding, and all-cause mortality.

338 patients were randomized to the LMWH group, and 338 were randomized to the VKA group. Baseline characteristics were similar among the two groups. 90% of patients had solid malignancies, and 67% of patients had metastatic disease. Within the VKA group, INR was estimated to be therapeutic 46% of the time, subtherapeutic 30% of the time, and supratherapeutic 24% of the time. Within the six-month follow-up period, symptomatic VTE occurred in 8.0% of the dalteparin group and 15.8% of the VKA group (HR 0.48, 95% CI 0.30-0.77, p=0.002; NNT = 12.9). The Kaplan-Meier estimate of recurrent VTE at 6 months was 9% in the dalteparin group and 17% in the VKA group. 6% of the dalteparin group developed major bleeding versus 6% of the VKA group (p = 0.27). 14% of the dalteparin group sustained any type of bleeding event versus 19% of the VKA group (p = 0.09). Mortality at 6 months was 39% in the dalteparin group versus 41% in the VKA group (p = 0.53).

In summary, treatment of VTE in cancer patients with low-molecular-weight heparin reduced the incidence of recurrent VTE relative to the incidence following treatment with vitamin K antagonists. Notably, this reduction in VTE recurrence was not associated with a change in bleeding risk. However, it also did not correlate with a mortality benefit either. This trial initiated a paradigm shift in the treatment of VTE in cancer. LMWH became the standard of care, although cost and convenience may have limited access and adherence to this treatment.

Until recently, no trial had directly compared a DOAC to LMWH in the prevention of recurrent VTE in malignancy. In an open-label, noninferiority trial, the Hokusai VTE Cancer Investigators demonstrated that the oral Xa inhibitor edoxaban (Savaysa) was noninferior to dalteparin with respect to a composite outcome of recurrent VTE or major bleeding. The 2018 SELECT-D trial compared rivaroxaban (Xarelto) to dalteparin and demonstrated a reduced rate of recurrence among patients treated with rivaroxaban (cumulative 6-month event rate of 4% versus 11%, HR 0.43, 95% CI 0.19–0.99) with no difference in rates of major bleeding but increased “clinically relevant nonmajor bleeding” within the rivaroxaban group.

Further Reading/References:
1. CLOT @ Wiki Journal Club
2. CLOT @ 2 Minute Medicine
3. UpToDate, “Treatment of venous thromboembolism in patients with malignancy”
4. Hokusai VTE Cancer Trial @ Wiki Journal Club
5. “Edoxaban for the Treatment of Cancer-Associated Venous Thromboembolism,” NEJM 2017
6. “Comparison of an Oral Factor Xa Inhibitor With Low Molecular Weight Heparin in Patients With Cancer With Venous Thromboembolism: Results of a Randomized Trial (SELECT-D).” J Clin Oncol 2018.

Summary by Duncan F. Moore, MD

Image Credit: Westgate EJ and FitzGerald GA, CC BY 2.5, via Wikimedia Commons

Week 52 – Donor-Feces Infusion for Recurrent C. difficile

“Duodenal Infusion of Donor Feces for Recurrent Clostridium difficile”

N Engl J Med. 2013 Jan 31;368(5):407-15. [free full text]
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Clostridioides (formerly Clostridium) difficile infection (CDI) is a common, increasingly prevalent, and increasingly recurrent disease. As discussed in the 2017-2018 Academic Year Week 43 post, the IDSA/SHEA guidelines published March 2018 now list vancomycin PO as first line treatment for initial, non-severe CDI. These guidelines also list fecal microbiota transplantation (FMT) as an option for treatment of a second or subsequent recurrence of CDI. FMT received a rating of “Strong [recommendation] / Moderate [level of evidence]” for this indication thanks to this 2013 trial by van Nood et al. – the first prospective RCT to compare antibiotic therapy to FMT in recurrent CDI.

This single-academic-center (Netherlands), open-label, randomized controlled trial compared three regimens for the treatment of recurrent CDI. One treatment arm received vancomycin 500mg PO QID x4-5 days followed by bowel lavage and then infusion of donor feces through nasoduodenal tube, another treatment arm received a standard 14-day vancomycin 500mg PO QID regimen, and the final treatment arm received a standard 14-day vancomycin regimen with additional bowel lavage on day 4 or 5. The primary endpoint was cure without relapse by 10 weeks.

43 patients were randomized prior to the termination of the trial due to the markedly higher rates of recurrent CDI among patients who did not receive FMT. Regarding the primary outcome, 13 (81%) of the FMT group were cured after the first infusion (and remained so) at 10 weeks, whereas resolution of CDI occurred in only 4 (31%) of the vancomycin-alone group and in only 3 (23%) of the vancomycin + bowel lavage group (p < 0.001 for both pairwise comparisons vs. FMT).

In this randomized controlled trial, fecal microbiota transplantation was superior to both vancomycin and vancomycin plus bowel lavage in the cure of recurrent Clostridium difficile infection. Although this trial was small, its effect was enormous. As mentioned above, FMT is now recommended by guidelines for the treatment of multiply-recurrent CDI. FMT has been the subject of numerous published and ongoing trials, including this notable 2017 study by Kao et al. that demonstrated noninferiority of FMT delivered via oral capsules versus “conventional” colonoscopic delivery.

Further Reading/References:
1. Wiki Journal Club
2. 2 Minute Medicine
3. 2017 Update to IDSA/SHEA Clinical Practice Guidelines for Clostridium difficile Infection
4. Kao et. al, “Effect of Oral Capsule- vs Colonoscopy-Delivered Fecal Microbiota Transplantation on Recurrent Clostridium difficile Infection.” JAMA. 2017;318(20):1985-1993.
5. IDSA, “Fecal Microbiota Transplantation”
6. Food and Drug Administration, “Enforcement Policy Regarding Investigational New Drug Requirements for Use of Fecal Microbiota for Transplantation to Treat Clostridium difficile Infection Not Responsive to Standard Therapies”

Summary by Duncan F. Moore, MD

Image Credit: CDC/ Lois S. Wiggs (PHIL #6260), Public Domain, via Wikimedia Commons

Week 51 – Rifaximin Treatment in Hepatic Encephalopathy

“Rifaximin Treatment in Hepatic Encephalopathy”

N Engl J Med. 2010 Mar25;362(12):1071-81. [free full text]
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As we are well aware at Georgetown, hepatic encephalopathy (HE) is highly prevalent among patients with cirrhosis, and admissions for recurrent HE place a significant burden on the medical system. The authors of this study note that HE is thought to result from “the systemic accumulation of gut-derived neurotoxins, especially ammonia, in patients with impaired liver function and portosystemic shunting.” Lactulose is considered the standard of care for the prevention of HE. It is thought to decrease the absorption of ammonia in the gut lumen through its cathartic effects and by alteration of colonic pH. The minimally absorbable oral antibiotic rifaximin is thought to further reduce ammonia production through direct antibacterial effects within the gut lumen. Thus the authors of this pivotal 2010 study sought to determine the additive effect of daily rifaximin prophylaxis in the prevention of HE.

The study enrolled adults with cirrhosis and 2+ episodes of overt HE during the past 6 months and randomized them to treatment with either rifaximin 550mg PO BID x6 months or placebo 550mg PO BID x6 months. The primary outcome was time to first breakthrough episode of HE (West Haven Score of 2+ or West Haven Score 0 –> 1 with worsening asterixis). Secondary outcomes included time to first hospitalization involving HE and adverse events, including those “possibly related to infection.”

299 patients were randomized. 140 and 159 patients were assigned to rifaximin and placebo, respectively. Baseline characteristics were similar among the two groups. Lactulose use prior to and during the study was similar in both groups at approximately 91%. Breakthrough HE occurred in 31 (22.1%) of the rifaximin patients and 73 (45.9%) of the placebo patients [HR 0.42, 95% CI 0.28-0.64, p<0.001, absolute risk reduction 23.7%, NNT = 4.2]. This result was consistent within all tested subgroups, except patients with MELD score 19-24 and patients who were not using lactulose at baseline. (See Figure 3.) Hospitalization involving HE occurred in 19 (13.6%) of the rifaximin patients and 36 (22.6%) of the placebo patients [HR 0.50, 95% CI 0.29-0.87, p = 0.01, absolute risk reduction 9.1%, NNT = 11.0]. There were no differences in adverse events among the two treatment groups.

Thus, prophylactic rifaximin reduced the incidence of recurrent HE and its resultant hospitalizations. This landmark trial showed a clear treatment benefit with implied savings in healthcare utilization costs associated with HE recurrences and hospitalizations. This marked effect was demonstrated even in the setting of relatively good (91%) lactulose adherence in both treatment arms prior to and throughout the trial.  On the day this trial was published in 2010, the FDA approved rifaximin for “reduction in risk of overt hepatic encephalopathy recurrence” in adults.

Because rifaximin is not generic and remains quite expensive, its financial utility is limited from an insurance company’s perspective. There is no other comparable nonabsorbable antibiotic for this indication. UpToDate suggests starting with lactulose therapy and then adding a nonabsorbable antibiotic, such as rifaximin, both for the treatment of overt HE and for the prevention of recurrent HE. In practice, most insurance companies will require a prior authorization for outpatient rifaximin treatment, but in my recent experience, this process has been perfunctory and easy.

Further Reading/References:
1. ClinicalTrials.gov, NCT00298038
2. FDA, NDA approval letter for Xifaxan (rifaximin)
3. UpToDate, “Hepatic encephalopathy in adults: Treatment”

Summary by Duncan F. Moore, MD

Week 50 – VERT

“Effects of Risedronate Treatment on Vertebral and Nonvertebral Fractures in Women With Postmenopausal Osteoporosis”

by the Vertebral Efficacy with Risedronate Therapy (VERT) Study Group

JAMA. 1999 Oct 13;282(14):1344-52. [free full text]
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Bisphosphonates are a highly effective and relatively safe class of medications for the prevention of fractures in patients with osteoporosis. The VERT trial published in 1999 was a landmark trial that demonstrated this protective effect with the daily oral bisphosphonate risedronate.

The trial enrolled post-menopausal women with either 2 or more vertebral fractures per radiography or 1 vertebral fracture with decreased lumbar spine bone mineral density. Patients were randomized to the treatment arm (risedronate 2.5mg PO daily or risedronate 5mg PO daily) to the daily PO placebo control arm. Measured outcomes included: 1) the prevalence of new vertebral fracture at 3 years follow-up, per annual imaging, 2) the prevalence of new non-vertebral fracture at 3 years follow-up, per annual imaging, and 3) change in bone mineral density, per DEXA q6 months.

2458 patients were randomized. During the course of the study, “data from other trials indicated that the 2.5mg risedronate dose was less effective than the 5mg dose,” and thus the authors discontinued further data collection on the 2.5mg treatment arm at 1 year into the study. All treatment groups had similar baseline characteristics. 55% of the placebo group and 60% of the 5mg risedronate group completed 3 years of treatment. The prevalence of new vertebral fracture within 3 years was 11.3% in the risedronate group and 16.3% in the placebo group (RR 0.59, 95% CI 0.43-0.82, p = 0.003; NNT = 20). The prevalence of new non-vertebral fractures at 3 years was 5.2% in the treatment arm and 8.4% in the placebo arm (RR 0.6, 95% CI 0.39-0.94, p = 0.02; NNT = 31). Regarding bone mineral density (BMD), see Figure 4 for a visual depiction of the changes in BMD by treatment group at the various 6-month timepoints. Notably, change from baseline BMD of the lumbar spine and femoral neck was significantly higher (and positive) in the risedronate 5mg group at all follow-up timepoints relative to the placebo group and at all timepoints except 6 months for the femoral trochanter measurements. Regarding adverse events, there was no difference in the incidence of upper GI adverse events among the two groups. GI complaints “were the most common adverse events associated with study discontinuance,” and GI events lead to 42% of placebo withdrawals but only 36% of the 5mg risedronate withdrawals.

Oral risedronate reduces the risk of vertebral and non-vertebral fractures in patients with osteoporosis while increasing bone mineral density. Overall, this was a large, well-designed RCT that demonstrated a concrete treatment benefit. As a result, oral bisphosphonate therapy has become the standard of care both for treatment and prevention of osteoporosis. This study, as well as others, demonstrated that such therapies are well-tolerated with relatively few side effects. A notable strength of this study is that it did not exclude patients with GI comorbidities.  One weakness is the modification of the trial protocol to eliminate the risedronate 2.5mg treatment arm after 1 year of study. Although this arm demonstrated a reduction in vertebral fracture at 1 year relative to placebo (p = 0.02), its elimination raises suspicion that the pre-specified analyses were not yielding the anticipated results during the interim analysis and thus the less-impressive treatment arm was discarded.

Further Reading/References:
1. Weekly alendronate vs. weekly risedronate [https://www.ncbi.nlm.nih.gov/pubmed/15619680]
2. Comparative effectiveness of pharmacologic treatments to prevent fractures: an updated systematic review (2014) [https://www.ncbi.nlm.nih.gov/pubmed/25199883]

Summary by Duncan F. Moore, MD

Image Credit: Nick Smith, CC BY-SA 3.0, via Wikimedia Commons

Week 49 – PARADIGM-HF

“Angiotensin-Neprilysin Inhibition versus Enalapril in Heart Failure”

N Engl J Med. 2014 Sep 11;371(11):993-1004. [free full text]

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Background:
Thanks to the CONSENSUS and SOLVD trials, angiotensin-converting enzyme (ACE) inhibitors have been a cornerstone of the treatment of heart failure with reduced ejection fraction (HFrEF) for years. Neprilysin is a neutral endopeptidase that degrades several peptides, including natriuretic peptides, bradykinin, and adrenomedullin. Inhibiting neprilysin increases levels of these substances and thus counteracts the neurohormonal overactivation of heart failure (which would otherwise lead to vasoconstriction, sodium retention, and maladaptive remodeling). Prior experimental data has demonstrated that, in terms of cardiovascular outcomes, neprilysin inhibition with an ARB is superior to ARB monotherapy. However, a clinical trial of concurrent neprilysin-inhibitor and ACE inhibitor therapy resulted in unacceptably high rates of serious angioedema. This study sought to show improved cardiac and mortality outcomes with neprilysin inhibition plus an ARB when compared to enalapril alone.

The study enrolled adults with NYHA class II, III, or IV heart failure, LVEF ≤ 35%, and BNP ≥ 150 or NT-proBNP ≥600. Pertinent exclusion criteria included symptomatic hypotension, SBP < 100mmHg at screening or 95mmHg at randomization, eGFR < 30 or decrease in eGFR by 25% between screening and randomization, K+ > 5.2, or history of angioedema/side effects to ACE inhibition or ARBs. Patients were randomized to treatment with either sacubitril/valsartan 200mg BID or to enalapril 10mg BID. (Screened patients were initially given sacubitril/valsartan followed by enalapril in single blinded run-in phases in order to ensure similar tolerance of the drugs prior to randomization.) The primary outcome was a composite of death from cardiovascular causes or first hospitalization for heart failure. Selected secondary outcomes included: 1) change from baseline in the clinical summary score of the Kansas City Cardiomyopathy Questionnaire (KCCQ), 2) time to new-onset atrial fibrillation, and 3) time to first occurrence of decline in renal function.

 

Results:
4187 patients were randomized to the sacubitril/valsartan group, and 4212 were randomized to the enalapril group.

The primary endpoint (composite death due to cardiovascular causes or first hospitalization for HF) occurred in 914 patients (21.8%) in the sacubitril/valsartan group and 1117 patients (26.5%) in the enalapril group (p < 0.001; NNT = 21). Death due to cardiovascular causes occurred 558 times in the sacubitril/valsartan group and 693 times in the enalapril group (13.3% vs. 16.5%, p < 0.001; NNT = 31). Hospitalization for heart failure occurred (at least once) 537 times in the sacubitril/valsartan group and 658 times in the enalapril group (12.8% vs. 15.6%, p < 0.001; NNT = 36).

Regarding secondary outcomes, the mean change in KCCQ score was a reduction of 2.99 points (i.e. a worsening of symptoms) in the sacubitril/valsartan group versus a reduction of 4.63 points in the enalapril group (p = 0.001). There was no significant group difference in time to new-onset atrial fibrillation or time to diminished renal function.

Regarding safety outcomes, patients in the sacubitril/valsartan group were more likely to have symptomatic hypotension compared to patients in the enalapril group (14.0% vs. 9.2%; p < 0.001; NNH = 21). However, patients in the enalapril group were more likely to have cough, serum creatinine ≥ 2.5, or potassium ≥6.0 compared to sacubitril/valsartan (p value varies, all significant). There was no group difference in rates of angioedema (p = 0.13).

Implication/Discussion:
In patients with HFrEF, inhibition of both angiotensin II and neprilysin with sacubitril/valsartan significantly reduced the risk of cardiovascular death or hospitalization for heart failure when compared to treatment with enalapril alone.

This study had several strengths. The treatment with sacubitril/valsartan was compared to treatment with a dose of enalapril that had previously been shown to reduce mortality when compared with placebo. Furthermore, the study used a run-in phase to ensure that patients could tolerate an enalapril dose that had previously been shown to reduce mortality. Finally, more patients in the enalapril group than in the sacubitril/valsartan group stopped the study drug due to adverse effects (12.3% vs. 10.7%, p = 0.03).

This study ushered in a new era in heart failure management and added a new medication class – Angiotensin Receptor-Neprilysin Inhibitors or ARNIs – to the arsenal of available heart failure drugs. Entresto (sacubitril/valsartan), the ARNI posterchild, has been advertised widely over the past several years. However, clinical use so far has been lower than expected (see http://www.cardiobrief.org/2017/12/05/after-slow-start-entresto-is-poised-for-takeoff/). Novartis, Entresto’s drug maker, is currently sponsoring PARAGON-HF, a trial of Entresto in patients with heart failure with preserved ejection fraction (HFpEF).

The 2017 ACC/AHA update to the guidelines for management of symptomatic HFrEF states that primary inhibition of the renin-angiotensin system with an ARNI in conjunction with evidence-based beta blockade and aldosterone antagonism is a Class I recommendation (Level B evidence). However, it does not favor this regimen over the Level-A-evidence regimens of an ARB or ACE inhibitor substituted for the ARNI. Yet the new guidelines also state that patients who have chronic symptomatic HFrEF of NYHA class II or III and tolerate an ACE inhibitor or ARB should substitute an ARNI for the ACE inhibitor or ARB in order to further reduce morbidity and mortality (Class I recommendation, level B evidence). See pages 15 and 17 here to read the details.

Bottom line:
Among patients with symptomatic HFrEF, treatment with an ARNI reduces cardiovascular mortality and HF hospitalizations when compared to treatment with enalapril. Due to this study’s impact, the use of ARNIs is now a Class I recommendation by the 2017 ACC/AHA guidelines for the treatment of HFrEF. Despite its higher cost, the use of sacubitril/valsartan appears to be cost-effective in terms of QALYs gained.

Further Reading/References:
1. PARADIGM-HF @ Wiki Journal Club
2. PARADIGM-HF @ 2 Minute Medicine
3. ACC/AHA 2017 Focused Update for Guideline Management of Heart Failure
4. CardioBrief, “After Slow Start Entresto Is Poised For Takeoff.”
5. PARAGON-HF @ ClinicalTrials.gov
6. McMurray et al., “Cost-effectiveness of sacubitril/valsartan in the treatment of heart failure with reduced ejection fraction.” Heart, 2017.

Summary by Patrick Miller, MD

Week 48 – SYMPLICITY HTN-3

“A Controlled Trial of Renal Denervation for Resistant Hypertension”

N Engl J Med. 2014 Apr 10;370(15):1393-401 [free full text]
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Approximately 10% of patients with hypertension have resistant hypertension (SBP > 140 despite adherence to three maximally tolerated doses of antihypertensives, including a diuretic). Evidence suggests that the sympathetic nervous system plays a large role in such cases, so catheter-based radiofrequency ablation of the renal arteries (renal denervation therapy) was developed as a potential treatment for resistant HTN. The 2010 SYMPLICITY HTN-2 trial was a small (n=106), non-blinded, randomized trial of renal denervation vs. continued care with oral antihypertensives that demonstrated a remarkable 30-mmHg greater decrease in SBP with renal denervation. Thus the 2014 SYMPLICITY HTN-3 trial was designed to evaluate the efficacy of renal denervation in a single-blinded trial with a sham-procedure control group.

The trial enrolled adults with resistant HTN with SBP ≥ 160 despite adherence to 3+ maximized antihypertensive drug classes, including a diuretic. (Pertinent exclusion criteria included secondary hypertension, renal artery stenosis > 50%, prior renal artery intervention.) Patients were randomized to either renal denervation with the Symplicity (Medtronic) radioablation catheter or to renal angiography only (sham procedure). The primary outcome was the mean change in office systolic BP from baseline at 6 months. (The examiner was blinded to intervention.) The secondary outcome was the change in mean 24-hour ambulatory SBP at 6 months. The primary safety endpoint was a composite of death, ESRD, embolic event with end-organ damage, renal artery or other vascular complication, hypertensive crisis within 30 days, or new renal artery stenosis of > 70%.

535 patients were randomized. On average, patients were receiving five antihypertensive medications. There was no significant difference in reduction of SBP between the two groups at 6 months. ∆SBP was -14.13 ± 23.93 mmHg in the denervation group vs. -11.74 ± 25.94 mmHg in the sham-procedure group for a between-group difference of -2.39 mmHg (95% CI -6.89 to 2.12, p = 0.26 with a superiority margin of 5 mmHg). The change in 24-hour ambulatory SBP at 6 months was -6.75 ± 15.11 mmHg in the denervation group vs. -4.79 ± 17.25 mmHg in the sham-procedure group for a between-group difference of -1.96 mmHg (95% CI -4.97 to 1.06, p = 0.98 with a superiority margin of 2 mmHg). There was no significant difference in the prevalence of the composite safety endpoint at 6 months with 4.0% of the denervation group and 5.8% of the sham-procedure group reaching the endpoint (percentage-point difference of -1.9, 95% CI -6.0 to 2.2).

In patients with resistant hypertension, renal denervation therapy provided no reduction in SBP at 6-month follow-up relative to a sham procedure.

This trial was an astounding failure for Medtronic and its Symplicity renal denervation radioablation catheter. The magnitude of the difference in results between the non-blinded, no-sham-procedure SYMPLICITY HTN-2 trial and this patient-blinded, sham-procedure-controlled trial is likely a product of 1) a marked placebo effect of procedural intervention, 2) Hawthorne effect in the non-blinded trial, and 3) regression toward the mean (patients were enrolled based on unusually high BP readings that over the course of the trial declined to reflect a lower true baseline).

Currently, there is no role for renal denervation therapy in the treatment of HTN (resistant or otherwise). However, despite the results of SYMPLICITY HTN-3, other companies and research groups are assessing the role of different radioablation catheters in patients with low-risk essential HTN and with resistant HTN. (For example, see https://www.ncbi.nlm.nih.gov/pubmed/29224639.)

Further Reading/References:
1. NephJC, SYMPLICITY HTN-3
2. UpToDate, “Treatment of resistant hypertension,” heading “Renal nerve denervation”

Summary by Duncan F. Moore, MD

Week 47 – STOPAH

“Prednisolone or Pentoxifylline for Alcohol Hepatitis”

aka the Steroids or Pentoxifylline for Alcoholic Hepatitis (STOPAH) trial

N Engl J Med. 2015 Apr 23;372(17):1619-28. [free full text]
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Severe alcoholic hepatitis is associated with short-term mortality as high as 30%. Treatment of alcoholic hepatitis with corticosteroids has been extensively studied and debated. Prior to this 2010 study, an analysis of the five largest studies of glucocorticoid treatment in alcoholic hepatitis concluded that there was a significant mortality benefit at 28 days among patients with severe disease. Similarly, the nonselective phosphodiesterase inhibitor pentoxifylline has been evaluated in alcoholic hepatitis. One of four RCTs showed a significant benefit, but two meta-analyses have not concluded that there is any benefit. The authors of the 2010 STOPAH trial sought to evaluate both therapies compared to placebos in a 2-by-2 factorial design.

The trial enrolled adults with a clinical diagnosis of alcoholic hepatitis, average alcohol consumption > 80 gm/day in men or 60 gm/day in women, total bilirubin > 4.7mg/dL, and a Maddrey discriminant function ≥ 32 [https://www.mdcalc.com/maddreys-discriminant-function-alcoholic-hepatitis]. Patients were randomized to one of the following four groups for 28 days of treatment.

      1. prednisolone-matched placebo daily + pentoxifylline-matched placebo TID
      2. prednisolone 40mg daily + pentoxifylline-matched placebo TID
      3. prednisolone-matched placebo daily + pentoxifylline 400mg TID
      4. prednisolone 40mg placebo daily + pentoxifylline 400mg TID

The primary outcome was 28-day mortality. The major secondary outcome was mortality or liver transplant at 90 days and at 1 year.

Regarding randomization of the 1103 patients, 276 were randomized to placebo-placebo, 277 to prednisolone-placebo, 276 to pentoxifylline-placebo, and 274 to prednisolone-pentoxifylline. The trial was stopped early due to “limitations on funding.” However, all enrolled patients completed at least 28 days of follow-up. 33 patients were unable to complete 90-day and 1-year follow-up due to termination of the trial.

At 28 days, 45 of 269 (17%) of placebo-placebo patients, 38 of 266 (14%) of prednisolone-placebo patients, 50 of 258 (19%) of pentoxifylline-placebo patients, and 35 of 260 (13%) of prednisolone-pentoxifylline patients had died. The odds ratio for 28-day mortality among patients treated with prednisolone was 0.72 (95% CI 0.52-1.01, p = 0.06), and the odds ratio for patients treated with pentoxifylline was 1.07 (95% CI 0.77-1.49, p = 0.69).

Similarly, neither treatment was found to influence 90-day or 1-year mortality or liver transplantation. (See Table 2.) Infection occurred in 13% of patients who received prednisolone versus 7% of patients who did not receive prednisolone.

Implication/Discussion:
In patients with severe alcoholic hepatitis, neither prednisolone nor pentoxifylline reduced morality risk at 28 days. Additionally, neither drug reduced the combined secondary endpoint of mortality or liver transplantation at 90 days or 1 year.

This was a well-designed, randomized, double-blind, double-placebo-controlled trial. A notable limitation was this trial’s reliance on the clinical diagnosis of alcohol hepatitis, rather than tissue diagnosis. This may have reduced the power of the trial with respect to detecting a treatment effect. Contemporary authors also noted that harm may have come to study patients due to a lack of tapering of prednisolone at the end of the 28 days of treatment.

A 2015 meta-analysis that included the STOPAH trial concluded that prednisolone treatment reduced 28-day mortality.

Despite the negative results of this specific trial, corticosteroid treatment has remained a mainstay of the treatment of severe alcoholic hepatitis.

The generally accepted practice, as summarized by UpToDate, is treatment with prednisolone 40mg PO daily for 28 days in patients with discriminant function ≥ 32. (Prednisolone is preferred over prednisone because prednisone requires conversion in the liver to its active form prednisolone, and such conversion can be impaired in liver dysfunction.) Therapy should be terminated early after 7 days if patients fail to show improvement (either by parameters such as bilirubin or discriminant function or by improvement in the Lille score).

Further Reading/References:
1. STOPAH @ Wiki Journal Club
2. STOPAH @ 2 Minute Medicine
3. UpToDate, “Management and prognosis of alcoholic hepatitis”
4. American College of Gastroenterology, “ACG Clinical Guideline: Alcoholic Liver Disease” (2018)
5. European Association for Study of the Liver (EASL), “EASL Clinical Practice Guidelines: Management of Alcoholic Liver Disease” (2012)

Summary by Duncan F. Moore, MD

Image Credit: University of Alabama at Birmingham Department of Pathology, CC BY-SA 2.5, via Wikimedia Commons

Week 46 – ACCORD

“Effects of Intensive Glucose Lowering in Type 2 Diabetes”

by the Action to Control Cardiovascular Risk in Diabetes (ACCORD) Study Group

N Engl J Med. 2008 Jun 12;358(24):2545-59. [free full text]
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We all treat type 2 diabetes mellitus (T2DM) on a daily basis, and we understand that untreated T2DM places patients at increased risk for adverse micro- and macrovascular outcomes. Prior to the 2008 ACCORD study, prospective epidemiological studies had noted a direct correlation between increased hemoglobin A1c values and increased risk of cardiovascular events. This correlation implied that treating T2DM to lower A1c levels would result in the reduction of cardiovascular risk. The ACCORD trial was the first large RCT to evaluate this specific hypothesis through comparison of events in two treatment groups – aggressive and less aggressive glucose management.

The trial enrolled patients with T2DM with A1c ≥ 7.5% and either age 40-79 with prior cardiovascular disease or age 55-79 with “anatomical evidence of significant atherosclerosis,” albuminuria, LVH, or ≥ 2 additional risk factors for cardiovascular disease (dyslipidemia, HTN, current smoker, or obesity). Notable exclusion criteria included “frequent or recent serious hypoglycemic events,” an unwillingness to inject insulin, BMI > 45, Cr > 1.5, or “other serious illness.” Patients were randomized to either intensive therapy targeting A1c to < 6.0% or to standard therapy targeting A1c 7.0-7.9%. The primary outcome was a composite first nonfatal MI or nonfatal stroke and death from cardiovascular causes. Reported secondary outcomes included all-cause mortality, severe hypoglycemia, heart failure, motor vehicle accidents in which the patient was the driver, fluid retention, and weight gain.

10,251 patients were randomized. The average age was 62, the average duration of T2DM was 10 years, and the average A1c was 8.1%. Both groups lowered their median A1c quickly, and median A1c values of the two groups separated rapidly within the first four months. (See Figure 1.) The intensive-therapy group had more exposure to antihyperglycemics of all classes. See Table 2.) Drugs were more frequently added, removed, or titrated in the intensive-therapy group (4.4 times per year versus 2.0 times per year in the standard-therapy group). At one year, the intensive-therapy group had a median A1c of 6.4% versus 7.5% in the standard-therapy group.

The primary outcome of MI/stroke/cardiovascular death occurred in 352 (6.9%) intensive-therapy patients versus 371 (7.2%) standard-therapy patients (HR 0.90, 95% CI 0.78-1.04, p = 0.16).

The trial was stopped early at a mean follow-up of 3.5 years due to increased all-cause mortality in the intensive-therapy group. 257 (5.0%) of the intensive-therapy patients died, but only 203 (4.0%) of the standard-therapy patients died (HR 1.22, 95% CI 1.01-1.46, p = 0.04). For every 95 patients treated with intensive therapy for 3.5 years, one extra patient died. Death from cardiovascular causes was also increased in the intensive-therapy group (HR 1.35, 95% CI 1.04-1.76, p = 0.02).

Regarding additional secondary outcomes, the intensive-therapy group had higher rates of hypoglycemia, weight gain, and fluid retention than the standard-therapy group. (See Table 3.) There were no group differences in rates of heart failure or motor vehicle accidents in which the patient was the driver.

Intensive glucose control of T2DM increased all-cause mortality and did not alter the risk of cardiovascular events. This harm was previously unrecognized.

The authors performed sensitivities analyses, including non-prespecified analyses, such as group differences in use of drugs like rosiglitazone, and they were unable to find an explanation for this increased mortality.

The target A1c level in T2DM remains a nuanced, patient-specific goal. Aggressive management may lead to improved microvascular outcomes, but it must be weighed against the risk of hypoglycemia. As summarized by UpToDate, while long-term data from the UKPDS suggests there may be a macrovascular benefit to aggressive glucose management early in the course of T2DM, the data from ACCORD suggest strongly that, in patients with longstanding T2DM and additional risk factors for cardiovascular disease, such management increases mortality.

The 2019 American Diabetes Association guidelines suggest that “a reasonable A1c goal for many nonpregnant adults is < 7%.” More stringent goals (< 6.5%) may be appropriate if they can be achieved without significant hypoglycemia or polypharmacy, and less stringent goals (< 8%) may be appropriate for patients “with a severe history of hypoglycemia, limited life expectancy, advanced microvascular or macrovascular complications…”

Of note, ACCORD also simultaneously cross-enrolled its patients in studies of intensive blood pressure management and adjunctive lipid management with fenofibrate. See this 2010 NIH press release and the links below for more information.

ACCORD Blood Pressure – NEJM, Wiki Journal Club

ACCORD Lipids – NEJM, Wiki Journal Club

Further Reading/References:
1. ACCORD @ Wiki Journal Club
2. ACCORD @ 2 Minute Medicine
3. American Diabetes Association – “Glycemic Targets.” Diabetes Care (2019).
4. “Effect of intensive treatment of hyperglycaemia on microvascular outcomes in type 2 diabetes: an analysis of the ACCORD randomised trial.” Lancet (2010).

Summary by Duncan F. Moore, MD

Week 45 – COURAGE

“Optimal Medical Therapy with or without PCI for Stable Coronary Disease”

by the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) Trial Research Group

N Engl J Med. 2007 Apr 12;356(15):1503-16 [free full text]
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The optimal medical management of stable coronary artery disease has been well-described. However, prior to the 2007 COURAGE trial, the role of percutaneous coronary intervention (PCI) in the initial management of stable coronary artery disease was unclear. It was known that PCI improved angina symptoms and short-term exercise performance in stable disease, but its mortality benefit and reduction of future myocardial infarction and ACS were unknown.

The trial recruited patients with stable coronary artery disease. (See paper for inclusion/exclusion criteria. Disease had to be sufficiently and objectively severe, but not too severe, and symptoms could not be sustained at the highest CCS grade.) Patients were randomized to either optimal medical management (including antiplatelet, anti-anginal, ACEi/ARB, and cholesterol-lowering therapy) and PCI or to optimal medical management alone. The primary outcome was a composite of all-cause mortality and non-fatal MI.

2287 patients were randomized. Both groups had similar baseline characteristics with the exception of a higher prevalence of proximal LAD disease in the medical-therapy group. Median duration of follow-up was 4.6 years in both groups. Death or non-fatal MI occurred in 18.4% of the PCI group and in 17.8% of the medical-therapy group (p = 0.62). Death, non-fatal MI, or stroke occurred in 20.0% of the PCI group and 19.5% of the medical-therapy group (p = 0.62). Hospitalization for ACS occurred in 12.4% of the PCI group and 11.8% of the medical-therapy group (p = 0.56). Revascularization during follow-up was performed in 21.1% of the PCI group but in 32.6% of the medical-therapy group (HR 0.60, 95% CI 0.51–0.71, p < 0.001). Finally, 66% of PCI patients were free of angina at 1-year follow-up compared with 58% of medical-therapy patients (p < 0.001). Rates were 72% and 67% at 3 years (p = 0.02) and 72% and 74% at five years (not significant).

Thus, in the initial management of stable coronary artery disease, PCI in addition to optimal medical management provided no mortality benefit over optimal medical management alone. However, initial management with PCI did provide a time-limited improvement in angina symptoms.

As the authors of COURAGE nicely summarize on page 1512, the atherosclerotic plaques of ACS and stable CAD are different. Vulnerable, ACS-prone plaques have thin caps and spread outward along the wall of the coronary artery, as opposed to stable CAD plaques, which have thick fibrous caps and are associated with inward-directed remodeling that narrows the artery lumen (and cause reliable angina symptoms and luminal narrowing on coronary angiography).

Notable limitations of this study:

      • Generalizability was limited due to the population, which was largely male, white, and 42% came from VA hospitals.
      • Drug-eluting stents were not clinically available until the last 6 months of the study, so most stents placed were bare metal.

Later meta-analyses were weakly suggestive of an association of PCI with improved all-cause mortality. It is thought that there may be a subset of patients with stable CAD who achieve a mortality benefit from PCI.

The 2017 ORBITA trial made headlines and caused sustained controversy when it demonstrated in a randomized trial that, in the context of optimal medical therapy, PCI did not increase exercise time more than did a sham PCI. Take note of the relatively savage author’s reply to commentary regarding the trial. See blog discussion here. The ORBITA-2 trial is currently underway.

The ongoing ISCHEMIA trial is both eagerly awaited and involved in a degree of controversy after a recent change in endpoints.

It is important to note that all of the above discussions assume that the patient does not have specific coronary artery anatomy (e.g. left main disease, multi-vessel disease with decreased LVEF) in which initial CABG would provide a mortality benefit. Finally, PCI should be considered in patients whose physical activity is limited by angina symptoms despite optimal medical therapy.

Further Reading:
1. COURAGE @ Wiki Journal Club
2. COURAGE @ 2 Minute Medicine
3. Canadian Cardiovascular Society grading of angina pectoris
4. ORBITA-2 @ ClinicalTrials.gov
5. ISCHEMIA @ ClinicalTrials.gov
6. Discussion re: ISCHEMIA trial changes @ CardioBrief

Summary by Duncan F. Moore, MD

Image Credit: National Institutes of Health, US Public Domain, via Wikimedia Commons