CRONICAS Cohort Study

Understanding the effects of rapid urbanization remains a challenge concerning chronic non-communicable diseases (NCDs). Peru offers a unique opportunity to assess the impact of geographical variation on NCDs. Comprehensive data generated by the CRONICAS Cohort Study across a diversity of scenarios has provided important advances towards understanding NCD burden and epidemiology in low- and middle-income countries.

The CRONICAS Cohort Study had two main aims. First, we evaluated the effects of variation in geographical settings on cardiovascular and chronic pulmonary diseases. Second, being aware of the reliance on biomass fuels, a feature that distinguishes low-resource settings from high-income countries, we are also looking into the longitudinal evaluation of lung function across different settings. Exposure to by-products of biomass fuel combustion is considered to be the most important risk factor for COPD after cigarette smoking.

This study was a joint effort between Johns Hopkins University and Universidad Peruana Cayetano Heredia. It was funded by the United States National Institutes of Health and has been implemented in three different sites with varying degrees of urbanization, outdoor and household air pollution exposures, and altitude above sea level (See Table).

Altitude Setting Vehicular Traffic Development Indoor Pollution
Lima Sea level Dense shantytown outside center of Lima Dense throughout the day Paved and dirt roads Primarily influenced by outdoor air pollution
Urban Puno 3,825 m
elevation
Dense city center Dense between 7am-7pm, otherwise minimal Primarily paved roads Primarily influenced by outdoor air pollution
Rural Puno 3,825 m
elevation
Farming communities far from city center Little to none. Bicycles and walking are the primary forms of transportation All dirt roads Indoor cookstoves
Tumbes Sea level Semi-urban setting with enrollment predominantly from farming communities far from city center Little to none. Bicycles and walking are the primary forms of transportation Primarily dirt roads Outdoor or semi-indoor cookstoves

Miranda JJ, Bernabe-Ortiz A, Smeeth L, Gilman RH, Checkley W; CRONICAS Cohort Study Group. Addressing geographical variation in the progression of non-communicable diseases in Peru: the CRONICAS cohort study protocol. BMJ Open 2012 2(1):e000610.