Trends and patterns of global health risk factors (2015-2019): a composite index approach across 100 countries...

Global health risk factors contribute significantly to mortality and morbidity worldwide, with diverse impacts across socio-economic groups. This study developed a composite index for health risk factors and subdomains, including nutrition, environmental risks, and non-communicable diseases, across 100 countries stratified by human development index (HDI) from 2015 to 2019. The index tracks disparities, trends, and associations with human development, aiding in resource allocation and informed policy-making for reducing health risks and improving global health outcomes.

A panel dataset comprising 100 countries, categorized into four HDI groups, was analyzed for the period 2015 to 2019. Health indicators were selected to construct a Health Risk Factors Index based on the World Health Organization's Global Reference List 2018. The development of the composite index and its sub-domains followed the United Nations Development Programme's methodology for data normalization, utilized Principal Component Analysis to determine weights, and employed the inverse normalized Euclidean distance formula for aggregation. Spearman's rank correlation was used to examine the relationships between the composite Health Risk Factors Index, its sub-indices, and the HDI.

The study revealed that very high HDI countries excelled in the Health Risk Factors Index and sub-indices for nutrition and environmental risks, indicating lower health risks. While low and medium HDI groups performed better in the non-communicable diseases index. Singapore achieved the highest health risk factors index scores in 2015 and 2019. A strong positive correlation was observed between HDI with composite and sub-indices of health risk factors and a negative correlation with sub-index of noncommunicable disease during 2015-2019.

The study highlights significant disparities in health risk factors across HDI groups, underscoring the need for tailored interventions. In general, very high and high HDI countries require focused efforts on noncommunicable disease-related health risk factors, while low and medium HDI countries should prioritize nutrition and environmental risks. Composite indices like the health risk factor index facilitate benchmarking and policy development, promoting accountability and targeted strategies for global health improvement.