Bariatric Surgery and Research: An Interview with Professor Ali Aminian

Updated: Nov 12, 2019

The IBC Newsletter is privileged to interview Professor. Ali Aminian to highlight on his phenomenal research work that is truly changing the bariatric world to the better. Dr. Aminian’s most recent paper “Association of Metabolic Surgery With Major Adverse Cardiovascular Outcomes in Patients With Type 2 Diabetes and Obesity” was published in the prestigious JAMA journal. It was highlighted upon in the New York Times, Wall Street Journal, Time Magazine, Apple News (to name a few). He is currently at Cleveland Clinic, Ohio and is a very active member in many societies (ASMBS, IFSO, SAGES..) that govern bariatric surgery.

Dr. Aminian, you have published several influential research papers on bariatric surgery. Where did it all start?

Thanks for this opportunity, Dr. Ghanem. When I look back to the past, generally speaking, I think I have been interested in two aspects of research: first, to provide answer for unanswered questions, and second, in metabolic research. I remember when my wife and I were medical students near 20 years ago in Shiraz, Iran, our research project was to assess the effects of unripe grape juice on blood lipid levels. There is a general belief in Iranian traditional medicine that unripe grape juice has lipid-lowering effects and that was one of my very first research projects. We were gavaging rabbits the egg yolks to induce hyperlipidemia and randomized them to different groups. Actually that was my first negative study too. Our findings did not support that general belief. I continued to be interested in research in the next several years and spent one full year as a research fellow in Bariatric and Metabolic Institute at Cleveland Clinic which further shaped my academic career.

What are the characteristics an academic bariatric surgeon researcher should have?

Passion, training, time, and support are 4 key elements for success. You have to be interested in research and you need research training and good mentorship. It definitely takes some of your clinical and family time to do high-quality research. Support from your department and institution would be necessary in terms of prioritizing research in your activities and providing protected time and fund.

Venous Thromboembolism in bariatric surgery continues to be a hot topic on IBC Facebook group. Knowing that you developed the postdischarge VTE risk assessment, can you share with us some details on it? Where can surgeons find it? And are there any updates for this risk calculator? Why was OCP use not included in your algorithm/risk stratification?

The risk calculator is available on the webpage and as a smartphone app (BariatricCalc). The risk calculator was constructed based on 10 independent risk factors of post-discharge VTE after bariatric surgery and all risk factors had odds ratio of at least 1.5. Unfortunately, we didn’t have data on OCP use to be considered in the risk modeling. Nonetheless, in our practice, we stop estrogen-containing OCPs 4 weeks before and 4 weeks after bariatric surgery for the fear of VTE and porto-splenic thrombosis. Exciting news would be that the second version of BariatricCalc containing more useful risk calculators will be released at Obesity Week 2019 Congress. I’m working on that now.

When it comes to diabetes, patients ask bariatric surgeons about the “best” procedure for them? Can you highlight on the “Individualized Metabolic Surgery Score or IMS Score for Procedure Selection”? Is it applicable in all cases?

The IMS Score can assist in choosing between RYGB and SG in patients with T2DM based on severity of T2DM before surgery. Data has come from the largest reported cohort of patients with T2DM (n=900) and at least 5-year data after RYGB and SG (median follow-up time of 7 years). Again, the calculator is available online and as a smartphone app. Other bariatric procedures such as DS, SADI, and single anastomosis gastric bypass were not included in the model, since we didn’t have high-quality long-term data after these procedures. The IMS score may not be as accurate if applies to patients with class I obesity or Asian ethnicity, since it was developed and validated based on cohorts from USA and Europe. The full article can be accessed through the link below:

The JAMA paper was a great success in all means. Can you please summarize why this paper is that essential? And why it got so much non-medical media exposure?

This matched-cohort study of near 14,000 patients showed that bariatric surgical procedures are associated with a striking 40% reduction in adverse cardiovascular events and death. Specifically, bariatric surgery was associated with 41% reduction in all-cause mortality, 62% reduction in heart failure, 31% reduction in heart attack, 33% reduction in stroke, 60% reduction in nephropathy, and 22% reduction in atrial fibrillation in 8 years. In another words, by operating on 13 patients, we can save 1 life. This remarkable reduction in cardiovascular events is unprecedented and has not been reported with any medication.

Do you believe this paper may encourage more medical doctors from the different specialties to refer patients for bariatric surgery?

I hope so. The findings were robust. First, the study showed that severe obesity and T2DM are really life-threating conditions. In 8 years, almost half of patients in the medical arm had at least one adverse cardiovascular event and 18% died. So, this is a very serious situation. Second, the study showed that the effects of obesity and T2DM on cardiovascular health can be reversible by substantial and sustained weight loss. The observed effect size of surgery was impressive. Publication in JAMA and discussion on social media would help to disseminate the message of this study.

With the abundance of the bariatric surgery research we are witnessing, do you believe the future research will be more on the physiological aspects of bariatric surgery or the technical aspects?

Both are important and will grow side by side. Research on the surgical techniques would can safety and efficacy of surgical procedures and will advance the field. Translational research is necessary to unlock the mechanisms of action of surgery which can lead to more effective therapies.

Ali Aminian M.D. Associate Professor of Surgery Cleveland Clinic, Ohio


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