Purpose: the prevalence of obesity is rapidly increasing in older adults. Information is required about what interventions are effective in reducing obesity and influencing health outcomes in this age group.
Design: systematic review and meta-analysis.
Data sources: thirteen databases were searched, earliest date 1966 to December 2008, including Medline, CINAHL, PsycINFO, the Cochrane database and EMBASE.
Study selection: we included studies with participants' mean age > or = 60 years and mean body mass index > or = 30 kg/m(2), with outcomes at a minimum of 1 year. Data were independently extracted by two reviewers and differences resolved by consensus.
Data extraction: nine eligible trials were included. Study interventions targeted diet, physical activity and mixed approaches. Populations included patients with coronary artery disease, diabetes mellitus and osteoarthritis.
Results: meta-analysis (seven studies) demonstrated a modest but significant weight loss of 3.0 kg [95% confidence interval (CI) 5.1-0.9] at 1 year. Total cholesterol (four studies) did not show a significant change: -0.36 mmol/l (95% CI -0.75 to 0.04). There was no significant change in high-density lipoprotein, low-density lipoprotein or triglycerides. In one study, recurrence of hypertension or cardiovascular events was significantly reduced (hazard ratio 0.65, 95% CI 0.50-0.85). Six-minute walk test did not significantly change in one study. Health-related quality of life significantly improved in one study but did not improve in a second study.
Conclusions: although modest weight reductions were observed, there is a lack of high-quality evidence to support the efficacy of weight loss programmes in older people.