A systematic review and meta-analysis
Miles D. Witham1 and Alison Avenell2
1 Section of Ageing and Health, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
2 Health Services Research Unit, University of Aberdeen, Aberdeen, UK
Address correspondence to: M. Witham. Tel: (+44) 1382 632436; Fax: (+44) 1382 660675. Email: firstname.lastname@example.org
Purpose: the prevalence of obesity is rapidly increasing inolder adults. Information is required about what interventionsare effective in reducing obesity and influencing health outcomesin this age group.
Design: systematic review and meta-analysis.
Data sources: thirteen databases were searched, earliest date1966 to December 2008, including Medline, CINAHL, PsycINFO,the Cochrane database and EMBASE.
Study selection: we included studies with participants’mean age 60 years and mean body mass index 30 kg/m2, with outcomesat a minimum of 1 year. Data were independently extracted bytwo reviewers and differences resolved by consensus.
Data extraction: nine eligible trials were included. Study interventionstargeted diet, physical activity and mixed approaches. Populationsincluded patients with coronary artery disease, diabetes mellitusand osteoarthritis.
Results: meta-analysis (seven studies) demonstrated a modestbut 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-densitylipoprotein, low-density lipoprotein or triglycerides. In onestudy, recurrence of hypertension or cardiovascular events wassignificantly 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 onestudy 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 efficacyof weight loss programmes in older people.
Keywords: obesity, older, weight loss, meta-analysis, elderly, systematic review