Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Oct 1;2(4):E306-17.
doi: 10.9778/cmajo.20140012. eCollection 2014 Oct.

Treatment for overweight and obesity in adult populations: a systematic review and meta-analysis

Leslea Peirson  1 , James Douketis  2 , Donna Ciliska  1 , Donna Fitzpatrick-Lewis  1 , Muhammad Usman Ali  1 , Parminder Raina  1
Affiliations

Treatment for overweight and obesity in adult populations: a systematic review and meta-analysis

Leslea Peirson et al. CMAJ Open. .

Abstract

Background: Obesity is a major public health issue. This review updates the evidence on the effectiveness of behavioural and pharmacologic treatments for overweight and obesity in adults.

Methods: We updated the search conducted in a previous review. Randomized trials of primary-care-relevant behavioural (diet, exercise and lifestyle) and pharmacologic (orlistat and metformin) with or without behavioural treatments in overweight and obese adults were included if 12-month, postbaseline data were provided for weight outcomes. Studies reporting harms were included regardless of design. Data were extracted and pooled wherever possible for 5 weight outcomes, 6 secondary health outcomes and 4 adverse events categories.

Results: We identified 68 studies, most consisted of short-term (≤ 12 mo) treatments using diet (n = 8), exercise (n = 4), diet and exercise (n = 10), lifestyle (n = 19), orlistat (n = 25) or metformin (n = 4). Compared with the control groups, intervention participants had a greater weight loss of -3.02 kg (95% confidence interval [CI] -3.52 to -2.52), a greater reduction in waist circumference of -2.78 cm (95% CI -3.34 to -2.22) and a greater reduction in body mass index of -1.11 kg/m(2) (95% CI -1.39 to -0.84). The relative risk for loss of ≥ 5% body weight was 1.77 (95% CI 1.58-1.99, [number needed to treat 5, 95% CI 4-7]), and the relative risk for loss of ≥ 10% body weight was 1.91 (95% CI 1.69-2.16, [number needed to treat 9, 95% CI 7-12]). Incidence of type 2 diabetes was lower among pre-diabetic intervention participants (relative risk 0.62 [95% CI 0.50-0.77], number needed to treat 17 [95% CI 13-29]). With prevalence rates for type 2 diabetes on the rise, weight loss coupled with a reduction in the incidence of type 2 diabetes could potentially have a significant benefit on population health and a possible reduction in need for drug treatments for glycemic control.

Interpretation: There is moderate quality evidence that behavioural and pharmacologic plus behvioural, treatments for overweight and obesity in adults lead to clinically important reductions in weight and incidence of type 2 diabetes in pre-diabetic populations.

Registration: PROSPERO no. CRD42012002753.

PubMed Disclaimer

Conflict of interest statement

Competing interests:Donna Ciliska and Parminder Raina have received grants from the Canadian Institutes of Health Research. James Douketis is a current member of the advisory boards for Bayer, Bristol-Myers Squibb, Sanofi and Pfizer. He was a member of the advisory boards for AstraZeneca, Boehringer Ingelheim, Biotie Therapies, Portola Pharmaceuticals and The Medicines Company. He also received speaker fees from AGEN Biomedical, Ortho-Janssen Pharmaceuticals and Boehringer Ingelheim, as well as a grant from Boehringer Ingelheim. No competing interests were declared by the other authors..

Figures

Figure 1:
Figure 1:
Search and selection flow diagram for articles on treatment of overweight and obesity in adults.
Figure 2A:
Figure 2A:
Effect of behavioural treatment interventions on weight in kilograms. Note: 1 = intervention arm 1; 2 = intervention arm 2; F = females only; M = males only: 1F, 2F and 3F represent female participants in different intervention arms; 1M and 2M represent male participants in different intervention arms; CI = confidence interval; DPP = Diabetes Prevention Program; SD = standard deviation.
Figure 2B:
Figure 2B:
Effect of pharmacologic plus behavioural treatment interventions on weight in kilograms. Note: 2 = intervention arm 2; CI = confidence interval; DPP = Diabetes Prevention Program; SD = standard deviation.
Figure 3:
Figure 3:
Effect of treatment interventions on loss of ≥ 5% baseline body weight: overall and by focus of intervention (behavioural and pharmacologic plus behavioural). Note: CI = confidence interval; F = females only.
See this image and copyright information in PMC

References

    1. Obesity and overweight Geneva (Switzerland): World Health Organization; 2014. Available: www.who.int/mediacentre/factsheets/fs311/en/ (accessed 2014 Sept. 17).
    1. Eckersley RM. Losing the battle of the bulge: causes and consequences of increasing obesity. Med J Aust 2001;174:590-2. - PubMed
    1. Mokdad AH, Ford ES, Bowman BA, et al. Prevalence of obesity, diabetes, and obesity-related health risk factors, 2001. JAMA 2003;289:76-9. - PubMed
    1. Wilson PW, D’Agostino RB, Sullivan L, et al. Overweight and obesity as determinants of cardiovascular risk: the Framingham experience. Arch Intern Med 2002;162:1867-72. - PubMed
    1. Flegal KM, Graubard BI, Williamson DF, et al. Excess deaths associated with underweight, overweight, and obesity. JAMA 2005;293:1861-7. - PubMed

LinkOut - more resources