In this update, we offer our "Slow Medicine" take on three topics that have caught some media attention over the past few weeks.
More Evidence Against Omega-3 Fatty Acid Supplementation
Do you recommend omega-3 fatty acid supplements to your patients with heart disease? If so, there may now be one less thing to do. Although the randomized controlled trials of omega-3 fatty acid supplementation for patients with known coronary heart disease (CHD) have had conflicting results, a new involving almost 78,000 participants from 10 RCTs found that omega-3 fatty acid supplements do not prevent any clinically important adverse outcomes. Nor does omega-3 supplementation look promising in any particular subgroup: "[A]fter adjustment for multiple testing, randomization of patients to study arms involving supplementation by omega-3 [fatty acids] had no significant association with major vascular events in any of the prespecified subgroups, including those defined by sex, history of CHD, history of diabetes, pretreatment levels of total cholesterol, high-density lipoprotein levels, low-density lipoprotein levels, triglyceride levels, or prior use of statin therapy. " This study confirms the in 2016 that supplementation with omega-3 fatty acids does not decrease the risk of cardiovascular disease.
In our view, these findings ought to lead to a reduction in the use of omega-3 supplements by the in favor of whole foods containing omega-3s. But we suspect that the impact of these new findings may be modes, as in 2016, given that companies are permitted to market omega-3 fatty acid as beneficial for "heart health" even when the totality of the scientific evidence suggests otherwise.
Coming Around on the New Zoster Vaccine
Though an ounce of prevention may be worth a pound of cure, not all vaccines are worth incorporating into clinical practice, as we explained recently in a in which we critique the Advisory Committee on Immunization Practices (ACIP) recommendation to add the pneumococcal conjugate vaccine to the adult vaccination schedule. In our view, providing pneumococcal conjugate vaccination does not add sufficient value to counterbalance the added complexity of the vaccine schedule.
For similar reasons, we have historically been skeptical of zoster vaccination among adults. Although herpes zoster can be a debilitating condition, the only vaccine approved for zoster prevention before last year -- Zoster Vaccine Live [Zostavax] -- simply doesn't work that well. Rigorous have shown that this live attenuated vaccine lowers the incidence of shingles over a 3-year period from about 3.3% to 1.6% in certain populations, but is much less efficacious in those over 70. Moreover, vaccine efficacy seems to wane substantially after a few years. Because of the small magnitude of the benefits, we always provided the vaccine to patients requesting it, but didn't use precious face time with our patients to actively promote it.
Recently, however, the FDA approved a new inactivated recombinant zoster vaccine (Zoster Vaccine Recombinant, Adjuvanted [Shingrix]) that seems to be more effective. According to involving adults ≥50 years old, the new vaccine was 97.2% efficacious in preventing zoster after three years, and in among adults ≥70 it proved 90% efficacious. In both studies, it also reduced the incidence of post-herpetic neuralgia -- the most important complication of the disease.
Important questions remain about the new inactivated zoster vaccine. Will its efficacy persist beyond 3-4 years? Will it be effective in real-world settings among diverse populations? Will it work among immunocompromised populations? Post-marketing surveillance studies -- which are notorious for never being completed -- will be needed to address these questions. Nevertheless, we endorse the , which now recommend the recombinant (administered in two doses) rather than the live attenuated vaccine for all adults ≥50 years old. Given the improved efficacy relative to the prior zoster vaccine, it may ultimately prove worth our effort to actively promote uptake of the vaccine among at-risk populations. For now, while we await post-marketing research, we will give the new recombinant zoster vaccine, rather than the older live attenuated vaccine, when patients request vaccination.
Growing Support for Sleeve Gastrectomy
We have long been proponents of Roux-en-Y gastric bypass to promote weight loss among carefully selected patients, especially those with diabetes. In recent years, use of sleeve gastrectomy, which involves a 70% vertical gastric resection without an intestinal bypass, has become increasingly common despite limited evidence for its efficacy. In fact, sleeve gastrectomy, which is technically less complex to perform than gastric bypass, has already overtaken gastric bypass as the most common bariatric surgery worldwide.
Two small but well-conducted randomized trials published recently in JAMA comparing gastric bypass directly with sleeve gastrectomy seem to support the recent promulgation of sleeve gastrectomy. In , 240 patients were randomized to either laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass and followed for 5 years. Gastric bypass was slightly more effect in respect to percent of excess weight loss (57% versus 49%) as well as partial or complete remission of diabetes (45% versus 37%). In , 217 morbidly obese patients were randomized to Roux-en-Y gastric bypass or sleeve gastrectomy and followed for 5 years. Excess BMI loss was not significantly different between the two surgical approaches. But some symptoms responded better to one approach than the other. Notably, gastric reflux resolved in 60% of patients undergoing gastric bypass but only 25% in patients randomized to sleeve gastrectomy. There was no statistically significant difference in re-operation rates between the two approaches.
In an excellent summarizing these and other recent findings, the authors argue that "these studies provide reassuring data to suggest that the rapid switch from Roux-en-Y gastric bypass to sleeve gastrectomy in the last decade has not been a therapeutic misadventure similar to the rise and fall of the adjustable gastric band." While we await longer term data, we will add sleeve gastrectomy to our evidence-based options for management of morbid obesity, especially for patients not suffering from gastric reflux.
"Updates in Slow Medicine" applies the latest medical research to support a thoughtful approach to clinical care. It is produced by , of Harvard Medical School, and , of the Keck School of Medicine at the University of Southern California. To learn more, .