Economic impact of adult obesity on health systems: a systematic review

Abstract
Background: Obesity represents an important public health issue. An assessment of its costs would be useful to provide recommendations for policy and decision-making strategies. The aims of our study were to carry out a systematic review to assess the economic burden of adult obesity in terms of direct and indirect costs and to perform a quality appraisal of the analysed studies. Methods: A literature search was carried out on PubMed, Scopus and Cochrane Library to retrieve cost-of-illness (COI) analyses focused on adult (aged 18 years or more) overweight or obese people and published up to 2013. COI analyses that considered direct and indirect costs were included. Each included manuscript was independently appraised by three groups of researchers on the basis of the British Medical Journal Drummond’s checklist. Results: Approximately 2044 articles were initially retrieved, and 17 were included in the current review. The included studies showed a medium–high-quality level. The available studies seemed to be heterogeneous both in terms of methodology and results reporting. However, as many studies have been conducted from the payer perspective, just direct medical costs can be considered exhaustive. As only three studies included considered also indirect costs, there is no strong evidence to give a comprehensive picture of this phenomenon also from the societal perspective. Conclusion: The review confirmed that obesity absorbs a huge amount of health-care resources. Further research is therefore needed to better understand the economic impact and to identify and promote public health strategies to tackle obesity.