Increase of body weight during the first year of intensive insulin treatment in type 2 diabetes: systematic review and meta-analysis

Abstract

This systematic review and meta-analysis was to evaluate the body weight increase and its clinical correlates, through direct weighted regressions, as well as the effect of different insulin regimens and insulin analogues, through meta-analysis. Appropriate methodology according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was adhered to. Forty-six randomized studies, published as full papers, reporting the effect of insulin treatment on change in body weight were identified, and used to identify predictors of weight change; studies were included in a meta-analysis to study the effect of different insulin regimens or insulin analogues on weight change. Intensity of treatment [aim of study (fasting blood glucose, mg/dl), dose of insulin, final HbA1c, change of HbA1c and frequency of hypoglycaemia] was significantly associated with body weight increase, with small differences between basal versus twice-a-day and prandial regimen. At meta-analysis, body weight increase was lower with basal regimen than with twice-a-day regimen and than with a prandial regimen. Within all regimens, body weight increase was lower with detemir than with NPH, with no difference between glargine and NPH; only two studies directly compared detemir and glargine, indicating lower weight gain with the former insulin. Within twice-a-day regimens and within prandial regimens, comparison was between newer analogues and older drugs, with no significant difference in body weight increase. Body weight increase during the first year of insulin treatment is associated with the intensity of treatment; body weight increase also depends on the insulin regimen applied.