Obesity and Diabetes

Abstract

Weight reduction is an integral part of the therapy of many patients with type 2 diabetes. The effectiveness of weight reduction in the treatment and prevention of type 2 diabetes has been proven by many studies. In the “Finnish Diabetes Prevention Study”, the conversion of prediabetes to type 2 diabetes was reduced by 58% through lifestyle intervention [1]. Similar results were obtained in the “Diabetes Prevention Program” [2]. An English study showed that for every 1 kg of weight lost in the first year after diagnosis of type 2 diabetes, life expectancy increases by 3−4 months [3], and Williamson et al. [4] showed that a weight reduction of 10 kg reduces overall mortality in people with type 2 diabetes by 25%. In addition, weight reduction not only improves blood glucose levels, but also virtually all comorbidities of diabetes simultaneously (hypertension, fatty liver disease, depression, obstructive sleep apnea syndrome [OSAS], etc.). However, these effects appear to be particularly strong when a weight reduction of at least 5% can be achieved [5]. Weight gain in type 2 diabetes treatment worsens cardiovascular risk factors and is associated with an increase in cardiovascular events and mortality [6]. From the 2018 consensus report of the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) and the 2019 update [7], it is clear that self-managed lifestyle intervention with weight reduction is of major importance in the treatment of type 2 diabetes. As a general treatment goal, patients with obesity and diabetes should aim for weight stabilization in the range of the normal weight (BMI 18.5−24.9 kg/m²). Since both an increased abdominal subcutaneous and visceral fat mass are associated with insulin resistance, measurement of waist circumference also serves as a good indicator of metabolic and cardiovascular risk and helps in the assessment of effective weight loss [8]. The BMI is also considered an independent predictor of cardiovascular events. However, waist circumference seems to be a better indicator of cardiovascular risk than BMI [9]. Women with a waist circumference≥80 cm and men with≥94 cm should not gain any further weight ([Table 1]). If the waist circumference is already at ≥88 cm for women and at ≥102 cm for men, the body weight should be reduced [9]. People with diabetes and a BMI of ≥25 kg/m² should aim to lose weight. At least 5% of the initial body weight should be lost within 6−12 months. This reduction of 5% already leads to a significant improvement in blood glucose levels. In people with diabetes and a BMI≥35 kg/m², the goal of weight reduction should be at least 10% of the starting weight. Once the weight reduction goals have been achieved, the treatment aims at long-term weight stabilization. Publication Date: 22 December 2020 (online) © 2020. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany