Comparison of laboratory-based and non-laboratory-based cardiovascular risk prediction tools in rural India

Non-laboratory-based cardiovascular risk prediction tools are feasible alternatives to laboratory-based tools in low- and middle-income countries. However, their effectiveness compared to their laboratory-based counterparts has not been adequately tested.

We compared estimates from laboratory-based and non-laboratory-based risk prediction tools in a low- and middle-income country setting.

Using a cross-sectional design, residents of the Rishi Valley region, Andhra Pradesh, India, were surveyed from 2012 to 2015. Ten-year absolute risk was compared for laboratory-based and non-laboratory-based Framingham Risk Score (FRS), World Health Organization-Risk Score (WHO-RS) and risk prediction tool for global populations (Globorisk). An agreement was assessed using ordinary least-products (OLP) regression (for RS) and quadratic weighted kappa (κ_w, for risk band).

Among 2847 participants aged 40-74 years, the mean age was 54.0 years. Cardiovascular RS increased with age and was greater in men than women in each age group. For all tools, regardless of whether laboratory or non-laboratory-based, over 80% of the participants were classified in the same risk band. There was strong agreement between laboratory-based and non-laboratory-based tools, greatest for the WHO-RS tools (OLP slope = 0.96, κ_w = 0.93) and least for the FRS (OLP slope = 0.84, κ_w = 0.88). The level of agreement was greater among women than men, less in those with hypercholesterolaemia or hypertension than those without, and was particularly poor among those with diabetes.

Non-laboratory-based Framingham, WHO-RS and Globorisk tools performed relatively well compared with their laboratory-based counterparts in rural India. However, they may be less useful for risk stratification when applied to individuals with diabetes.