Weight regain may not erode improvement in CV risk due to weight loss at five years

"Data from the review shows that even though most people who lose weight after behavioural weight-management programs eventually regain some of the eight, their risk for cardiovascular disease appears to be lower for at least five years after the program ends," the researchers wrote in their study.

Behavioural weight loss programs are known to enhance weight loss in the short term, but longer-term cardiometabolic effects are uncertain since the lost weight is commonly regained. Therefore, Jamie Hartmann-Boyce, University of Oxford, Oxford, United Kingdom, and colleagues aimed to assess the impact of weight regain after BWMPs (behavioural weight management programs) on cardiovascular risk factors, diabetes, and cardiovascular disease.

For this purpose, the researchers used 11 databases, trial registries, and forward-citation searching to identify published articles. They included Randomized trials of BWMPs in adults with obesity reporting cardiometabolic outcomes at ≥12 months at and after the program end. Differences were synthesized between more intensive interventions and comparator groups using meta-regression, mixed-effects, and time-to-event models to evaluate the impact of weight regain on the incidence and risk of cardiovascular disease.

One hundred twenty-four trials with a median follow-up of 28 months after program end reporting on ≥1 cardiometabolic outcomes were included. The median baseline participant BMI (body mass index) was 33 kg/m2; the median age was 51.

The authors reported the following findings:

· Fifteen and 8 study arms (4202 and 7889 participants, respectively) examined the incidence of type 2 diabetes and CVD, respectively, with imprecise evidence of a lower incidence for at least five years.

· weight regains in BWMPs relative to comparators reduced these differences.

· One and five years after the program ended, systolic BP (blood pressure) was 1.5 mm mercury and 0.4 mm lower (84 studies; 30 836 participants), the total cholesterol/HDL (high-density lipoprotein) ratio was 1.5 points lower at both times (82 studies; 19 003 participants), and HbA1c (%) 0.38 lower at both times (94 studies; 28 083 participants).

· Of the included studies, 22% were judged at high risk of bias; removing these did not meaningfully change results.

To conclude, BWMPs reduce cardiometabolic risk factors with effects lasting at least five years following the completion of the program, despite weight regain.

"Evidence that they reduce the incidence of cardiovascular disease or diabetes is less certain," the researchers wrote. "Few studies followed participants for ≥5 years."

Reference:

Hartmann-Boyce J, Theodoulou A, Oke JL, Butler AR, Bastounis A, Dunnigan A, Byadya R, Cobiac LJ, Scarborough P, Hobbs FDR, Sniehotta FF, Jebb SA, Aveyard P. Long-Term Effect of Weight Regain Following Behavioral Weight Management Programs on Cardiometabolic Disease Incidence and Risk: Systematic Review and Meta-Analysis. Circ Cardiovasc Qual Outcomes. 2023 Mar 28:e009348. doi: 10.1161/CIRCOUTCOMES.122.009348. Epub ahead of print. PMID: 36974678.