New analysis of data indicates that, despite subsequent weight regain, participants in behavioural weight-management programmes (BWMPs) show improvements in several cardiovascular risk factors for at least 5 years after the invention ends.
Largely driven by cardiovascular disease, obesity is a major risk factor for premature morbidity and mortality. BWMPs enhance weight loss in the short term, but are typically followed by weight regain. Their longer-term cardiometabolic effects are uncertain. This large systematic review and meta-analysis, by Hartmann-Boyce and colleagues, assessed whether weight regain after the end of interventions was associated with changes in cardiometabolic risk and incident disease.
The investigators analysed data from 124 randomised controlled trials of BWMPs with adult participants with overweight or obesity, that reported changes in cardiovascular risk factors, diabetes or cardiovascular disease following the end of the programme. The median follow-up was 28 months. Differences were assessed between these intensive interventions and comparator groups.
At 1 year and 5 years after the BWMPs ended, total cholesterol/high-density lipoprotein (HDL) ratio was 1.5 points lower both times (82 studies; n=19,003); systolic blood pressure was 1.5 and 0.4 mmHg lower (84 studies; n=30,836); and HbA1c was 0.38% lower both times (94 studies; n=28,083).
There were also indications that cardiovascular disease and type 2 diabetes incidence were lower at 5 years in the intervention arms (10 studies; n=4202), but the evidence was too sparse to draw high-certainty conclusions.
There was clear evidence that BWMPs lowered cardiovascular risk compared to comparator groups, and that the improvement was apparent for at least 5 years (although gradually eroding as weight was regained). While acknowledging a number of study limitations, the authors concluded that support for weight management reduces the risk of premature morbidity, and that weight regain is unlikely to erode the lifetime benefits.
The study can be read in full here.
