Outcomes of a specialist weight management programme in the UK National Health Service: prospective study of 1838 patients

OBJECTIVES: There is limited evidence on the effectiveness of weight management programmes provided within routine healthcare and inconsistent use of outcome measures. Our aim was to evaluate a large National Health Service (NHS) weight management service and report absolute and proportional weight losses over 12 months. DESIGN: Prospective observational study. SETTING: Glasgow and Clyde Weight Management Service (GCWMS), which provides care for residents of NHS Greater Glasgow and Clyde area (population 1.2 million). PARTICIPANTS: All patients who began GCWMS between 1 October 2008 and 30 September 2009. INTERVENTIONS: Structured educational lifestyle programme employing cognitive behavioural therapy, 600 kcal deficit diet, physical activity advice, lower calorie diet and pharmacotherapy. PRIMARY AND SECONDARY OUTCOMES MEASURES: Baseline observation carried forward (BOCF), last observation carried forward (LOCF) and changes in programme completers reported using outcomes of absolute 5 kg and 5% weight losses and mean weight changes at a variety of time points. RESULTS: 6505 referrals were made to GCWMS, 5637 were eligible, 3460 opted in and 1916 (34%) attended a first session. 78 patients were excluded from our analysis on 1838 patients. 72.9% of patients were women, mean age of all patients at baseline was 49.1 years, 43.3% lived in highly socioeconomically deprived areas and mean weights and body mass indices at baseline were 118.1 kg and 43.3 kg/m(2), respectively. 26% lost ≥5 kg by the end of phase 1, 30% by the end of phase 2 and 28% by the end of phase 3 (all LOCF). Weight loss was more successful among men, particularly those ≤29 years old. CONCLUSIONS: Routine NHS weight management services may achieve moderate weight losses through a comprehensive evidence-based dietary, activity and behavioural approach including psychological care. Weight losses should be reported using a range of outcome measures so that the effectiveness of different services can be compared.