Effects of bariatric surgery in different obesity phenotypes: Tehran Obesity Treatment Study (TOTS)



Not all morbid obese patients suffer from metabolic co-morbidities; thus, a sub-group of metabolically healthy morbid obese (MHMO) individuals are identified. However, the role of bariatric surgery is not well understood in this subgroup.


A total of 2244 morbid obese individuals aged 18–65 years undergoing bariatric surgery were selected. Patients were considered MHMO according to the joint interim statement (JIS) definition, as having two or less abnormalities in these five parameters: waist circumference (WC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), systolic or diastolic blood pressure (SBP or DBP), and fasting plasma glucose (FPG). Otherwise, they were considered metabolically unhealthy morbid obese (MUMO). Follow-up data were collected at 6, 12, and 24 months post-surgery.


Prior to surgery, 36.2% of participants were MHMO and had significantly lower BMI, WC, TG, FPG, SBP, and DBP and higher HDL-C compared to MUMO. Both MHMO and MUMO participants showed a significant decrease in BMI, WC, TG, SBP, DBP, and FPG and increase in HDL-C and the percentage of excess weight loss (%EWL). Two-year post-operative changes (from baseline) of BMI, WC, and %EWL were greater in MHMO subjects and changes of TG, HDL-C, DBP, SBP, and FPG were greater in MUMO subjects. Further multivariate regression analysis for delta (∆) change in these characteristics revealed that only the delta (∆) changes of WC and %EWL were statistically different between the two phenotypes and were greater in MHMO subjects, 2 years after the surgery (− 3.077 cm decrease in WC and + 3.612% higher %EWL compared to MUMO subjects).


Bariatric surgery is an effective method for reduction of metabolic abnormalities and weight loss in both MUMO and MHMO phenotypes. Benefits of this intervention are comparable between patients with these two obesity phenotypes.

This is a preview of subscription content, log in to check access.

Access options

Buy single article

Instant unlimited access to the full article PDF.

US$ 39.95

Price includes VAT for USA

Subscribe to journal

Immediate online access to all issues from 2019. Subscription will auto renew annually.

US$ 99

This is the net price. Taxes to be calculated in checkout.

Fig. 1


  1. 1.

    Van Gaal LF, Mertens IL, De Block CE. Mechanisms linking obesity with cardiovascular disease. Nature. 2006;444(7121):875–80.

  2. 2.

    Karelis AD. Metabolically healthy but obese individuals. Lancet (London, England). 2008;372(9646):1281–3.

  3. 3.

    Phillips CM. Metabolically healthy obesity: definitions, determinants and clinical implications. Reviews in endocrine & metabolic disorders. 2013;14(3):219–27.

  4. 4.

    Jung CH, Lee WJ, Song KH. Metabolically healthy obesity: a friend or foe? The Korean journal of internal medicine. 2017;32(4):611–21.

  5. 5.

    Phillips CM. Metabolically healthy obesity across the life course: epidemiology, determinants, and implications. Annals of the New York Academy of Sciences. 2017;1391(1):85–100.

  6. 6.

    Guh DP, Zhang W, Bansback N, et al. The incidence of co-morbidities related to obesity and overweight: a systematic review and meta-analysis. BMC public health. 2009;9:88.

  7. 7.

    Mingrone G, Panunzi S, De Gaetano A, et al. Bariatric surgery versus conventional medical therapy for type 2 diabetes. The New England journal of medicine. 2012;366(17):1577–85.

  8. 8.

    McTigue KM, Harris R, Hemphill B, et al. Screening and interventions for obesity in adults: summary of the evidence for the U.S. Preventive Services Task Force. Annals of internal medicine. 2003;139(11):933–49.

  9. 9.

    Picot J, Jones J, Colquitt JL, et al. The clinical effectiveness and cost-effectiveness of bariatric (weight loss) surgery for obesity: a systematic review and economic evaluation. Health technology assessment (Winchester, England). 2009;13(41):1–190. 215-357, iii-iv

  10. 10.

    Stelmach-Mardas M, Walkowiak J. Dietary interventions and changes in cardio-metabolic parameters in metabolically healthy obese subjects: a systematic review with meta-analysis. Nutrients. 2016;8:8.

  11. 11.

    Athyros VG, Tziomalos K, Karagiannis A, et al. Cardiovascular benefits of bariatric surgery in morbidly obese patients. Obesity reviews : an official journal of the International Association for the Study of Obesity. 2011;12(7):515–24.

  12. 12.

    Karelis AD, Messier V, Brochu M, Rabasa-Lhoret R. Metabolically healthy but obese women: effect of an energy-restricted diet. Diabetologia. 2008;51(9):1752-4.

  13. 13.

    Kantartzis K, Machann J, Schick F, et al. Effects of a lifestyle intervention in metabolically benign and malign obesity. Diabetologia. 2011;54(4):864–8.

  14. 14.

    Sesti G, Folli F, Perego L, et al. Effects of weight loss in metabolically healthy obese subjects after laparoscopic adjustable gastric banding and hypocaloric diet. PloS one. 2011;6(3):e17737.

  15. 15.

    Pelascini E, Disse E, Pasquer A, et al. Should we wait for metabolic complications before operating on obese patients? Gastric bypass outcomes in metabolically healthy obese individuals. Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2016;12(1):49–56.

  16. 16.

    Barzin M. Hosseinpanah F. Bariatric surgery for morbid obesity: Tehran Obesity Treatment Study (TOTS) rationale and study design. 2016;5(1):e8.

  17. 17.

    Gösta S. Physical status: the use and interpretation of anthropometry. WHO Technical Report Series. Acta Paediatrica. 1997;86(3):280.

  18. 18.

    Alberti KG, Eckel RH, Grundy SM, et al. Harmonizing the metabolic syndrome: a joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention; National Heart, Lung, and Blood Institute; American Heart Association; World Heart Federation; International Atherosclerosis Society; and International Association for the Study of Obesity. Circulation. 2009;120(16):1640–5.

  19. 19.

    Delavari A, Forouzanfar MH, Alikhani S, et al. First nationwide study of the prevalence of the metabolic syndrome and optimal cutoff points of waist circumference in the Middle East: the national survey of risk factors for noncommunicable diseases of Iran. Diabetes care. 2009;32(6):1092–7.

  20. 20.

    Rey-Lopez JP, de Rezende LF, Pastor-Valero M, et al. The prevalence of metabolically healthy obesity: a systematic review and critical evaluation of the definitions used. Obesity reviews : an official journal of the International Association for the Study of Obesity. 2014;15(10):781–90.

  21. 21.

    Lin H, Zhang L, Zheng R, et al. The prevalence, metabolic risk and effects of lifestyle intervention for metabolically healthy obesity: a systematic review and meta-analysis: a PRISMA-compliant article. Medicine. 2017;96(47):e8838.

  22. 22.

    Karelis AD, Messier V, Brochu M, et al. Metabolically healthy but obese women: effect of an energy-restricted diet. Diabetologia. 2008;51(9):1752–4.

  23. 23.

    Arsenault BJ, Cote M, Cartier A, et al. Effect of exercise training on cardiometabolic risk markers among sedentary, but metabolically healthy overweight or obese post-menopausal women with elevated blood pressure. Atherosclerosis. 2009;207(2):530–3.

  24. 24.

    Goday A, Benaiges D, Parri A, et al. Can bariatric surgery improve cardiovascular risk factors in the metabolically healthy but morbidly obese patient? Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2014;10(5):871–6.

  25. 25.

    Jimenez A, Perea V, Corcelles R, et al. Metabolic effects of bariatric surgery in insulin-sensitive morbidly obese subjects. Obesity surgery. 2013;23(4):494–500.

  26. 26.

    Gastrointestinal surgery for severe obesity. Consensus statement National Institutes of Health Consensus Development Conference. 1991;9(1):1-20.

  27. 27.

    Phillips CM, Perry IJ. Does inflammation determine metabolic health status in obese and nonobese adults? The Journal of clinical endocrinology and metabolism. 2013;98(10):E1610–9.

Download references


The authors would like to thank the hospital staff, study assistants, and coordinators that took part in this research. The authors would also like to thank Dr. Forough Ghanbari for critically editing English grammar and syntax of the manuscript.

Funding information

This work was funded by the Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Author information

Correspondence to Farhad Hosseinpanah.

Ethics declarations

Conflict of Interest

The authors declare that they have no conflict of interest.

Statement of Informed Consent

Informed consent was obtained from all individual participants included in the study.

Human Rights/Ethical Approval

This study has been approved by the Human Research Review Committee of the Endocrine Research Center, Shahid Beheshti University of Medical Sciences, No. 2ECRIES 93/03/13.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Barzin, M., Aryannezhad, S., Khalaj, A. et al. Effects of bariatric surgery in different obesity phenotypes: Tehran Obesity Treatment Study (TOTS). OBES SURG 30, 461–469 (2020).

Download citation


  • Bariatric surgery
  • Morbid obesity
  • Obesity phenotype