Appointment adherence, weight reduction, and retention at 9 months in Australian clinical obesity services: a retrospective cohort study

OBJECTIVE: This study aimed to compare demographic, clinical, and early engagement characteristics between participants retained and not retained at 9 months in specialist obesity services. METHODS: This retrospective cohort study analysed 235 records of patients (mean body mass index 49.2 kg/m²) from eight Australian specialist obesity services. Participants were classified as retained (n = 153) and not retained (n = 82) at 9 months. Demographic variables and baseline comorbidities were examined to identify potential predictors of retention. Appointment adherence and weight reduction outcomes during the first 6 months were also analysed according to retention status. Descriptive statistics and appropriate comparative tests were used to test the differences between groups. RESULTS: Baseline demographic characteristics were similar between participants retained and not retained at 9 months. Type 2 diabetes was more prevalent among participants retained compared with those not retained (55.6% vs 39.0%; P = 0.02). Eating disorders (7.8% vs 22.0%; P = 0.002), gallstones (1.9% vs 8.6%; P = 0.04), and prior stroke (0.6% vs 8.6%; P = 0.003) were more common in participants who were not retained. Retention at 9 months was associated with significantly higher appointment adherence throughout the study period, with the greatest difference in cumulative 9-month adherence (0.88 vs 0.77, P < 0.001). At 6 months, retained participants achieved significantly greater weight reduction (-9.02 kg ± 10.29 kg vs -5.78 kg ± 10.55 kg; P = 0.04). CONCLUSIONS: In this cohort, 9-month retention was strongly associated with early appointment adherence and greater 6-month weight reduction. Non-retained patients clustered with eating disorders and prior stroke indicate patients requiring additional support. Early adherence and weight reduction appear key to sustained engagement.