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Association of Weight Loss Achieved Through Metabolic Surgery With Risk and Severity of COVID-19 Infection

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To identify the key insights or developments described in this article
1 Credit CME
Key Points

Question  Is substantial weight loss achieved with weight loss surgery associated with improved risk and severity of COVID-19 infection in patients with obesity?

Findings  In this cohort study of 11 809 patients with obesity, the rates of positive SARS-CoV-2 test results were comparable among patients in the surgical group and control group. However, previous weight loss surgery was significantly associated with a 49% lower risk of hospitalization, 63% lower risk of need for supplemental oxygen, and 60% lower risk of severe disease during a 12-month period after contracting COVID-19 infection.

Meaning  The findings from this study show an association between weight loss achieved with surgery and improved outcomes of COVID-19 infection, suggesting that obesity can be a modifiable risk factor for the severity of COVID-19 infection.


Importance  Obesity is an established risk factor for severe COVID-19 infection. However, it is not known whether losing weight is associated with reduced adverse outcomes of COVID-19 infection.

Objective  To investigate the association between a successful weight loss intervention and improved risk and severity of COVID-19 infection in patients with obesity.

Design, Setting, and Participants  This cohort study involved adult patients with a body mass index of 35 or higher (calculated as weight in kilograms divided by height in meters squared) who underwent weight loss surgery between January 1, 2004, and December 31, 2017, at the Cleveland Clinic Health System (CCHS). Patients in the surgical group were matched 1:3 to patients who did not have surgical intervention for their obesity (control group). The source of data was the CCHS electronic health record. Follow-up was conducted through March 1, 2021.

Exposures  Weight loss surgery including Roux-en-Y gastric bypass and sleeve gastrectomy.

Main Outcomes and Measures  Distinct outcomes were examined before and after COVID-19 outbreak on March 1, 2020. Weight loss and all-cause mortality were assessed between the enrollment date and March 1, 2020. Four COVID-19–related outcomes were analyzed in patients with COVID-19 diagnosis between March 1, 2020, and March 1, 2021: positive SARS-CoV-2 test result, hospitalization, need for supplemental oxygen, and severe COVID-19 infection (a composite of intensive care unit admission, need for mechanical ventilation, or death).

Results  A total of 20 212 patients (median [IQR] age, 46 [35-57] years; 77.6% female individuals [15 690]) with a median (IQR) body mass index of 45 (41-51) were enrolled. The overall median (IQR) follow-up duration was 6.1 (3.8-9.0) years. Before the COVID-19 outbreak, patients in the surgical group compared with control patients lost more weight (mean difference at 10 years from baseline: 18.6 [95% CI, 18.4-18.7] percentage points; P < .001) and had a 53% lower 10-year cumulative incidence of all-cause non–COVID-19 mortality (4.7% [95% CI, 3.7%-5.7%] vs 9.4% [95% CI, 8.7%-10.1%]; P < .001). Of the 20 212 enrolled patients, 11 809 were available on March 1, 2020, for an assessment of COVID-19–related outcomes. The rates of positive SARS-CoV-2 test results were comparable in the surgical and control groups (9.1% [95% CI, 7.9%-10.3%] vs 8.7% [95% CI, 8.0%-9.3%]; P = .71). However, undergoing weight loss surgery was associated with a lower risk of hospitalization (adjusted hazard ratio [HR], 0.51; 95% CI, 0.35-0.76; P < .001), need for supplemental oxygen (adjusted HR, 0.37; 95% CI, 0.23-0.61; P < .001), and severe COVID-19 infection (adjusted HR, 0.40; 95% CI, 0.18-0.86; P = .02).

Conclusions and Relevance  This cohort study found that, among patients with obesity, substantial weight loss achieved with surgery was associated with improved outcomes of COVID-19 infection. The findings suggest that obesity can be a modifiable risk factor for the severity of COVID-19 infection.

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Article Information

Accepted for Publication: October 7, 2021.

Published Online: December 29, 2021. doi:10.1001/jamasurg.2021.6496

Corresponding Author: Steven E. Nissen, MD, Cleveland Clinic Coordinating Center for Clinical Research, Department of Cardiovascular Medicine, Cleveland Clinic, 9500 Euclid Ave, Mail Code JB-20, Cleveland, OH 44195 (nissens@ccf.org).

Author Contributions: Dr Aminian had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Aminian.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Aminian, Milinovich.

Critical revision of the manuscript for important intellectual content: Aminian, Tu, Wolski, Kattan, Nissen.

Statistical analysis: Tu, Milinovich, Wolski, Kattan.

Obtained funding: Aminian.

Administrative, technical, or material support: Aminian, Nissen.

Supervision: Aminian, Nissen.

Conflict of Interest Disclosures: Dr Aminian reported receiving research support and speaking honoraria from Medtronic outside the submitted work. Mr Milinovich reported receiving grants from NovoNordisk, Novartis, Boehringer Ingelheim, Merck, Bayer, National Institutes of Health, and the National Football League Players Association as well as personal fees from American Association for Thoracic Surgery outside the submitted work. Dr Nissen reported receiving grants from Novartis, Eli Lilly, Abbvie, Silence Therapeutics, AstraZeneca, Esperion Therapeutics, Amgen, and Bristol Myers Squibb outside the submitted work. No other disclosures were reported.

Funding/Support: This study was funded by grant ERP-2021-12614 from Medtronic.

Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Meeting Presentation: This study was presented in part in the Latest Science Session at the European Society of Cardiology Congress; August 27, 2021; online.

Additional Contributions: Greg Strnad, MS, and Robert Burton, BS, Cleveland Clinic, helped in the collection of some data. These individuals received no additional compensation, outside of their usual salary, for their contributions.

Popkin  BM , Du  S , Green  WD ,  et al.  Individuals with obesity and COVID-19: a global perspective on the epidemiology and biological relationships.   Obes Rev. 2020;21(11):e13128. doi:10.1111/obr.13128 PubMedGoogle Scholar
Stefan  N , Birkenfeld  AL , Schulze  MB .  Global pandemics interconnected—obesity, impaired metabolic health and COVID-19.   Nat Rev Endocrinol. 2021;17(3):135-149. doi:10.1038/s41574-020-00462-1 PubMedGoogle ScholarCrossref
Gao  M , Piernas  C , Astbury  NM ,  et al.  Associations between body-mass index and COVID-19 severity in 6·9 million people in England: a prospective, community-based, cohort study.   Lancet Diabetes Endocrinol. 2021;9(6):350-359. doi:10.1016/S2213-8587(21)00089-9PubMedGoogle ScholarCrossref
de Siqueira  JVV , Almeida  LG , Zica  BO , Brum  IB , Barceló  A , de Siqueira Galil  AG .  Impact of obesity on hospitalizations and mortality, due to COVID-19: A systematic review.   Obes Res Clin Pract. 2020;14(5):398-403. doi:10.1016/j.orcp.2020.07.005PubMedGoogle ScholarCrossref
Földi  M , Farkas  N , Kiss  S ,  et al; KETLAK Study Group.  Obesity is a risk factor for developing critical condition in COVID-19 patients: a systematic review and meta-analysis.   Obes Rev. 2020;21(10):e13095. doi:10.1111/obr.13095 PubMedGoogle Scholar
Mingrone  G , Panunzi  S , De Gaetano  A ,  et al.  Metabolic surgery versus conventional medical therapy in patients with type 2 diabetes: 10-year follow-up of an open-label, single-centre, randomised controlled trial.   Lancet. 2021;397(10271):293-304. doi:10.1016/S0140-6736(20)32649-0 PubMedGoogle ScholarCrossref
Schauer  PR , Bhatt  DL , Kirwan  JP ,  et al; STAMPEDE Investigators.  Bariatric surgery versus intensive medical therapy for diabetes—5-year outcomes.   N Engl J Med. 2017;376(7):641-651. doi:10.1056/NEJMoa1600869 PubMedGoogle ScholarCrossref
Ikramuddin  S , Korner  J , Lee  WJ ,  et al.  Lifestyle intervention and medical management with vs without Roux-en-Y gastric bypass and control of hemoglobin A1c, LDL cholesterol, and systolic blood pressure at 5 years in the Diabetes Surgery Study.   JAMA. 2018;319(3):266-278. doi:10.1001/jama.2017.20813 PubMedGoogle ScholarCrossref
Cohen  RV , Pereira  TV , Aboud  CM ,  et al.  Effect of gastric bypass vs best medical treatment on early-stage chronic kidney disease in patients with type 2 diabetes and obesity: a randomized clinical trial.   JAMA Surg. 2020;155(8):e200420. doi:10.1001/jamasurg.2020.0420 PubMedGoogle Scholar
O’Brien  R , Johnson  E , Haneuse  S ,  et al.  Microvascular outcomes in patients with diabetes after bariatric surgery versus usual care: a matched cohort study.   Ann Intern Med. 2018;169(5):300-310. doi:10.7326/M17-2383 PubMedGoogle ScholarCrossref
Arterburn  DE , Telem  DA , Kushner  RF , Courcoulas  AP .  Benefits and risks of bariatric surgery in adults: a review.   JAMA. 2020;324(9):879-887. doi:10.1001/jama.2020.12567 PubMedGoogle ScholarCrossref
Aminian  A , Zajichek  A , Arterburn  DE ,  et al.  Association of metabolic surgery with major adverse cardiovascular outcomes in patients with type 2 diabetes and obesity.   JAMA. 2019;322(13):1271-1282. doi:10.1001/jama.2019.14231 PubMedGoogle ScholarCrossref
Sjöström  L , Peltonen  M , Jacobson  P ,  et al.  Association of bariatric surgery with long-term remission of type 2 diabetes and with microvascular and macrovascular complications.   JAMA. 2014;311(22):2297-2304. doi:10.1001/jama.2014.5988 PubMedGoogle ScholarCrossref
Fisher  DP , Johnson  E , Haneuse  S ,  et al.  Association between bariatric surgery and macrovascular disease outcomes in patients with type 2 diabetes and severe obesity.   JAMA. 2018;320(15):1570-1582. doi:10.1001/jama.2018.14619 PubMedGoogle ScholarCrossref
Carlsson  LMS , Sjöholm  K , Jacobson  P ,  et al.  Life expectancy after bariatric surgery in the Swedish Obese Subjects Study.   N Engl J Med. 2020;383(16):1535-1543. doi:10.1056/NEJMoa2002449 PubMedGoogle ScholarCrossref
Syn  NL , Cummings  DE , Wang  LZ ,  et al.  Association of metabolic-bariatric surgery with long-term survival in adults with and without diabetes: a one-stage meta-analysis of matched cohort and prospective controlled studies with 174 772 participants.   Lancet. 2021;397(10287):1830-1841. doi:10.1016/S0140-6736(21)00591-2PubMedGoogle ScholarCrossref
Milinovich  A , Kattan  MW .  Extracting and utilizing electronic health data from Epic for research.   Ann Transl Med. 2018;6(3):42. doi:10.21037/atm.2018.01.13 PubMedGoogle ScholarCrossref
Grambsch  PM , Therneau  TM .  Proportional hazards tests and diagnostics based on weighted residuals.   Biometrika. 1994;81(3):515-526. doi:10.1093/biomet/81.3.515 Google ScholarCrossref
van Buuren  S , Groothuis-Oudshoorn  K .  mice: multivariate imputation by chained equations in R.   J Stat Softw. 2011;45(3):1-67. doi:10.18637/jss.v045.i03 Google Scholar
Bhatt  DL , Aminian  A , Kashyap  SR ,  et al.  Cardiovascular biomarkers after metabolic surgery versus medical therapy for diabetes.   J Am Coll Cardiol. 2019;74(2):261-263. doi:10.1016/j.jacc.2019.04.058 PubMedGoogle ScholarCrossref
Zhang  C , Zhang  J , Liu  W , Chen  X , Liu  Z , Zhou  Z .  Improvements in humoral immune function and glucolipid metabolism after laparoscopic sleeve gastrectomy in patients with obesity.   Surg Obes Relat Dis. 2019;15(9):1455-1463. doi:10.1016/j.soard.2019.05.021 PubMedGoogle ScholarCrossref
Aminian  A , Fathalizadeh  A , Tu  C ,  et al.  Association of prior metabolic and bariatric surgery with severity of coronavirus disease 2019 (COVID-19) in patients with obesity.   Surg Obes Relat Dis. 2021;17(1):208-214. doi:10.1016/j.soard.2020.10.026 PubMedGoogle ScholarCrossref
Iannelli  A , Bouam  S , Schneck  AS ,  et al.  The impact of previous history of bariatric surgery on outcome of COVID-19. A nationwide medico-administrative French study.   Obes Surg. 2021;31(4):1455-1463. doi:10.1007/s11695-020-05120-z PubMedGoogle ScholarCrossref
Aminian  A , Tu  C .  Association of bariatric surgery with clinical outcomes of SARS-CoV-2 infection: a systematic review and meta-analysis in the initial phase of COVID-19 pandemic.   Obes Surg. 2021;31(6):2419-2425. doi:10.1007/s11695-020-05213-9 PubMedGoogle ScholarCrossref
Rubino  F , Cohen  RV , Mingrone  G ,  et al.  Bariatric and metabolic surgery during and after the COVID-19 pandemic: DSS recommendations for management of surgical candidates and postoperative patients and prioritisation of access to surgery.   Lancet Diabetes Endocrinol. 2020;8(7):640-648. doi:10.1016/S2213-8587(20)30157-1 PubMedGoogle ScholarCrossref
Aminian  A , Kermansaravi  M , Azizi  S ,  et al.  Bariatric surgical practice during the initial phase of COVID-19 outbreak.   Obes Surg. 2020;30(9):3624-3627. doi:10.1007/s11695-020-04617-x PubMedGoogle ScholarCrossref
Executive Council of ASMBS.  Safer through surgery: American Society for Metabolic and Bariatric Surgery statement regarding metabolic and bariatric surgery during the COVID-19 pandemic.   Surg Obes Relat Dis. 2020;16(8):981-982. doi:10.1016/j.soard.2020.06.003 PubMedGoogle ScholarCrossref
Belanger  MJ , Hill  MA , Angelidi  AM , Dalamaga  M , Sowers  JR , Mantzoros  CS .  Covid-19 and disparities in nutrition and obesity.   N Engl J Med. 2020;383(11):e69. doi:10.1056/NEJMp2021264 PubMedGoogle Scholar
Townsend  MJ , Kyle  TK , Stanford  FC .  Outcomes of COVID-19: disparities in obesity and by ethnicity/race.   Int J Obes (Lond). 2020;44(9):1807-1809. doi:10.1038/s41366-020-0635-2 PubMedGoogle ScholarCrossref
Dicker  D , Bettini  S , Farpour-Lambert  N ,  et al.  Obesity and COVID-19: the two sides of the coin.   Obes Facts. 2020;13(4):430-438. doi:10.1159/000510005 PubMedGoogle ScholarCrossref
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