Intentional Weight Loss and Longevity in Overweight Patients with Type 2 Diabetes: A Population-Based Cohort Study

PLoS One. 2016 Jan 25;11(1):e0146889. doi: 10.1371/journal.pone.0146889. eCollection 2016.

Abstract

Objective: This study examined the influence of weight loss on long-term morbidity and mortality in overweight (BMI≥25 kg/m2) patients with type 2 diabetes, and tested the hypothesis that therapeutic intentional weight loss supervised by a medical doctor prolongs life and reduces the risk for cardiovascular disease in these patients.

Methods: This is a 19 year cohort study of patients in the intervention arm of the randomized clinical trial Diabetes Care in General Practice. Weight and prospective intentions for weight loss were monitored every third month for six years in 761 consecutive patients (≥40 years) newly diagnosed with diabetes in general practices throughout Denmark in 1989-92. Multivariable Cox regression was used to estimate the association between weight change during the monitoring period (year 0 to 6) and the outcomes during the succeeding 13 years (year 6 to 19) in 444 patients who were overweight at diagnosis and alive at the end of the monitoring period (year 6). The analysis was adjusted for age, sex, education, BMI at diagnosis, change in smoking, change in physical activity, change in medication, and the Charlson comorbidity 6-year score. Outcomes were from national registers.

Results: Overall, weight loss regardless of intention was an independent risk factor for increased all-cause mortality (P<0.01). The adjusted hazard ratio for all-cause mortality, cardiovascular mortality, and cardiovascular morbidity attributable to an intentional weight loss of 1 kg/year was 1.20 (95%CI 0.97-1.50, P = 0.10), 1.26 (0.93-1.72, P = 0.14), and 1.06 (0.79-1.42, P = 0.71), respectively. Limiting the analysis to include only those patients who survived the first 2 years after the monitoring period did not substantially change these estimates. A non-linear spline estimate indicated a V-like association between weight change and all-cause mortality, suggesting the best prognosis for those who maintained their weight.

Conclusions: In this population-based cohort of overweight patients with type 2 diabetes, successful therapeutic intentional weight loss, supervised by a doctor over six years, was not associated with reduced all-cause mortality or cardiovascular morbidity/mortality during the succeeding 13 years.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Body Mass Index
  • Body Weight
  • Cohort Studies
  • Denmark
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / mortality*
  • Diabetes Mellitus, Type 2 / physiopathology
  • Female
  • Health Status
  • Humans
  • Intention
  • Longevity / physiology*
  • Male
  • Middle Aged
  • Overweight / complications
  • Overweight / mortality*
  • Overweight / physiopathology
  • Risk Factors
  • Survival Rate
  • Weight Loss / physiology*

Grants and funding

The authors received no specific funding for this paper. The DCGP trial was supported by the Danish Medical Research Council, The Danish Research Foundation for General Practice, The Health Insurance Foundation, The Danish Ministry of Health, Novo Nordisk Farmaka Denmark Ltd., The Pharmacy Foundation, The Foundation for General Practice in Copenhagen, Frederiksberg, Tårnby and Dragør, The Doctor Sofus Carl Emil Friis and his Wife Olga Doris Friis Trust, The Danish Medical Association Research Fund, The Velux Foundation, The Rockwool Foundation, Novo Nordisk Ltd., The Danish Diabetes Association, Oda and Hans Svenningsen’s Fund, The A P Møller Foundation for the Advancement of Medical Science, Captain Axel Viggo Mørch and his Wife’s Trust, The Danish Eye Health Society, Mogens and Jenny Vissing’s Trust, and Bernhard and Marie Klein’s Trust. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.