Systematic Review into City Interventions to Address Childhood Obesity

Abstract

Background: Childhood obesity threatens to undo the gains we have made in life expectancy over the last two centuries.  It disproportionately affects lower socioeconomic and ethnic minority groups and has become one of the most important global health challenges of the 21st century. Whilst obesity is not confined to city populations, cities are home to more than half of the world’s population with concentrated groups at high risk of obesity.  Cities have also long been the engine-room of social and technological change that has led to our current obesogenic environment. The aim of this study was to systematically identify city-wide interventions to address childhood obesity and provide a practical assessment with recommendations for policy makers, health system leaders and political leaders in other cities.  

Methods: Systematic review, conducted according to PRISMA guidelines, examining Embase, Ovid Medline, Central, Scopus, Campbell Library, CINALH, Health Business Elite; Health Management Information Consortium (HMIC), PyschINFO and  Prospero. Studies that described a city-wide intervention to reduce childhood obesity were included, irrespective of study design or perceived methodological quality. Only studies in English language were included.  This manuscript represents thematic analysis of a sub-set of data from the Prospero study, registration number: CRD42020166210  

Findings: Our search yielded 42,137 original citations of which 1614 met the inclusion criteria and 96 were coded as relating to childhood obesity. The 96 citations, ranging in year of publication 1997 to 2019,  were conducted in 36 cities, with 13 citations either not stating a city or covering multiple cities, across 5 continents.  The highest proportion of publications were from North America (59 / 96) and in particular the USA (56/96) and New York City (23/96).  The primary outcome indicators that were extracted were: reduction in obesity, reduction in weight and/or reduction in BMI. This was stated in only one quarter of the identified studies (24/96).  Where this was not stated a secondary impact measure was identified and recorded. Overall there was high degree of  heterogeneity of study design and reporting of impact, with a majority being descriptive texts using qualitative instruments of assessment.  The studies were analysed thematically with the following 7 areas of intervention emerging; schools and childcare settings(27); education and support programmes(20); multi-component(17); healthy food availability(11); physical infrastructure(11); restaurants and food outlets(6) and marketing and nutritional labelling(4).  

Interpretation: Multi-level and multi-component interventions, at the individual, community and city level, done in concert, are needed to address childhood obesity.  A composite of interventions that cities can utilise to address childhood obesity is provided. These interventions will also be beneficial to the environment and make the case that personal health and planetary health are inextricably linked and should be considered as one.

Funding Statement: None.

Declaration of Interests: None.

Keywords: city, cities, mayor, childhood obesity