Association between indicators of inequality and weight change following a behavioural weight loss intervention.
Obesity facts 2022
Birch JM, Mueller J, Sharp SJ, Griffin SJ, Kelly MP, Halford JCG, and Ahern AL
DOI : 10.1159/000528135
PubMed ID : 36521444
URL : https://www.karger.com/Article/Abstract/528135
Weight loss through behavioural weight management interventions can have important health benefits for people with obesity. However, to maximise the health benefits, weight lost must be maintained. Evidence suggests that behavioural weight loss interventions do not exacerbate inequalities in the short-term. However, no study has yet considered whether inequalities exist in long-term weight change following intervention.
To investigate if there are inequalities in weight change following weight loss intervention.
We conducted a cohort analysis of data from the Weight Loss Referrals for Adults in Primary Care (WRAP) trial (N=1267). WRAP randomised participants to receive a brief intervention information booklet or vouchers for 12-weeks or 52-weeks of WW (formerly Weight Watchers) and followed them for 5-years. Multiple linear regression estimated the association between exposures (indicators of inequality) and outcome (change in weight between 1- and 5-years). Each model was adjusted for intervention group, baseline weight, weight change between baseline and 1-year, research centre, and source of the 5-year weight data.
Of the 1267 participants in WRAP, 708 had weight change data available. Mean weight change between 1- and 5-years was +3.30 kg (SD 9.10 kg). A 1 year difference in age at baseline was associated with weight change of 0.11kg ((95%CI 0.06, 0.16), p<0.001). We did not find evidence of associations between ethnicity, gender, education, indices of multiple deprivation, household income, or other family members participating in a weight loss programme and weight change.
Except for age, we did not find evidence of inequalities in weight change following a behavioural intervention. Findings further support the use of behavioural weight management interventions as part of a systems wide approach to improving population health.
Weight loss through behavioural weight management programmes can have important health benefits for people living with obesity.
These programmes are often delivered via commercial organisations, such as WW (formerly Weight Watchers). Maintaining weight loss that comes from attending these interventions is often difficult. It is important that we identify if there are groups in the population (such people of a certain age, gender, ethnicity, or income level) that may face more difficulties in maintaining weight loss from a weight management programme.
If there are differences in the amount of weight loss maintained by age, gender, ethnicity, or income level, then this may indicate health inequalities being widened by weight loss programmes. Health inequalities are differences in health or things that affect health between different groups of people.
To explore this, we analysed data from a study that considered how much weight people lost from 12 or 52 weeks of WW compared to those who received a brief advice booklet. There was data available for 708 participants, who were all people living with overweight or obesity.
We found that, between 1- and 5-years of follow up from when the participants were recruited into the study, that there was a difference in the amount of weight loss maintained by age, but not by other characteristics (gender, ethnicity, and income). Our analyses showed that older age was associated with maintaining more weight loss. A ten-year increase in age was associated with maintaining an additional 1.1kg of weight loss.
Our results show that younger participants, who may have greater work and caring responsibilities, may have more difficulties in maintaining weight loss from a weight management programme.