Impact of anti-obesity medication initiation and duration on weight loss in a comprehensive weight loss programme.

OBJECTIVE: This retrospective study aimed to evaluate the impact of anti-obesity medication (AOM) initiation, usage and duration on weight loss in a 72-week precision obesity programme. The type of AOM, diet and exercise plan was chosen based upon an individual's biological and psychosocial needs. The 72-week study duration allowed for a fair investigation of the downstream impact of delayed versus early AOM initiation. METHODS: Participants, aged ≥18 years with body mass index ≥30 kg m-2, enrolled from 1 March 2015 to 1 April 2017, were included. Subgroups were assigned by AOM usage (users versus non-users, early [before 8 weeks] versus delayed [after 8 weeks] AOM initiation and short [<6 months] versus long [≥6 months] AOM duration). Primary endpoints included change in baseline weight at 72 weeks and proportions achieving ≥5%, ≥10% and ≥15% weight loss. Outcomes were compared between subgroups. RESULTS: Mean age and body mass index (N = 129) were 45.0 ± 14.0 years and 37.0 ± 6.0 kg m-2, respectively; 67% were female. At week 72, AOM users (N = 71) achieved significantly greater mean percentage reduction in baseline weight than non-users (N = 58). On average, baseline weight decreased by 14.04 ± 6.2% in users versus 10.9 ± 6.8% in non-users (P = 0.008); 84% and 94% of non-user and AOM users lost >5% weight loss (P = 0.006). A higher proportion of users lost ≥15% of weight (45.1% vs. 19.0%; P < 0.001). Mean percentage reduction in weight was greater for early versus delayed starters (-17.60 ± 5.3% vs. -13.95 ± 5.5%; P = 0.024), and longer AOM usage trended towards increased weight loss. CONCLUSION: Early initiation of AOM may enhance weight loss.