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.