Long-term weight control improves blood sugar levels in diabetes, finds Study

Loss of glucose‐lowering efficacy over time has commonly been found in existing long‐term studies regardless of monotherapy, combination therapy or insulin treatment. Weight loss is associated with improvement in beta‐cell function and a decreased need for treatment. However, the association between changes in HbA1c and body weight and their relationships with beta‐cell function in terms of maintaining glycaemic control or blood sugar control in diabetes treatment are not clear. For this purpose, researchers of the Huazhong University of Science and Technology, Wuhan, China conducted a study to analyse quantitatively the association between the durability of blood sugar control and body weight changes during treatment.

It was a meta-analysis that comprised observational studies including pharmacotherapy, dietary and bariatric surgery interventions. Researchers searched the following electronic bibliographic databases: MEDLINE, EMBASE, PsycINFO, Global Health, The Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Methodology Register), Health Technology Assessment Database, and Web of Science (Science and Social Science Citation Index). They included Studies with follow‐ups >12 months, and final and intermediate assessments of haemoglobin A1c (HbA1c) and body weight. They extracted and synthesized four outcomes assessing therapeutic durability using Stata statistical software, including changes in HbA1c, goal-achievement rate, failure rate and coefficient of failure (CoF).

Key findings of the study were:

♦ After 8.9 months of treatment, researchers found the HbA1c levels declined from 8.03% to 7.15% and then gradually increased up to 7.72% after 5 years.

♦ They also noted that the goal‐achievement rate decreased from 54.8% (after 1 year of treatment) to 19.4% after 5 years because of the rebound of HbA1c. Poor weight control (regain of body weight) is the major reason for this rebound.

♦ The CoF was 0.123 ± 0.022%/year. After stratification, the researchers noted CoFs were 0.224 ± 0.025%/year for weight gain, 0.137 ± 0.034%/year for neutral weight and −0.024 ± 0.032%/year for weight loss. Which implies the weight gain and neutral weight is positively associated with the coefficient of failure, whereas weight loss is negatively associated with it.

♦ Upon stratification by treatment approaches, they noted the CoFs were 0.45%/year for insulin, 0.43%/year for sulphonylurea, 0.34%/year for thiazolidinediones, 0.29%/year for metformin, 0.16% for glucagon‐like polypeptide‐1 receptor agonists, 0.12% for surgery, −0.03% for sodium‐glucose cotransporter‐2 inhibitors( SGLT2 I) and −0.21% for dipeptidyl peptidase‐IV inhibitors (DPP4i) . This implies that glycaemic control was maintained in groups that received treatment with agents without weight‐gain effects, particularly SGLT2i and DPP4i.

The authors concluded, "Our review shows that long‐term weight control was associated with the prevention of beta function deterioration and improvement in glycaemic maintenance. Modest weight loss with a goal of 2‐3% of body weight should be recommended to improve therapeutic durability and prevent beta‐cell deterioration". The review shows that glycaemic control was maintained in groups that received treatment with agents without weight‐gain effects, particularly SGLT2i and DPP4i. At least 2% body weight loss was associated with the maintenance of therapeutic efficacy. 

For further information:

https://dom-pubs.onlinelibrary.wiley.com/doi/10.1111/dom.14217