The prevalence of hypertension increased between 1990 and 2020 in both urban and rural areas of low- and middle-income countries (LMICs), but the rural trend was more pronounced. The study was recently published in the journal Plos Medicine under the direction of the Barcelona Institute of Global Health (ISGlobal), a centre supported by the “la Caixa” Foundation.
The research team analysed nearly 300 studies containing data from more than 19.7 million people in 66 low- and middle-income countries (LMICs) and discovered that the prevalence of hypertension in urban areas (30.5%) was slightly higher than in rural areas (27.5%). The total disparity was only 2.45%. This disparity was smaller for the period 2005-2020 than it was for the period 1990-2004, and trends indicate that hypertension increased more rapidly in rural areas than in urban ones. As countries progress socioeconomically, the prevalence of hypertension in rural areas approaches or even surpasses that of urban areas.
This faster growth in rural areas could be partially attributed to the rural population ageing as a result of youth emigration. Increasing levels of outdoor air pollution as a result of socioeconomic development, in addition to air pollution in rural homes caused by the use of inefficient cooking and lighting fuels, may also play a role. Urbanization is also associated with a shift toward sedentary habits (less physically demanding occupations) and unhealthy diets.
Although urban areas have been the focus of hypertension prevention research, “if the global burden of hypertension is to be reduced, more attention must be paid to rural areas,” says Otavio T. Ranzani, ISGlobal researcher and lead author of the study.
Although hypertension is one of the world’s leading risk factors for morbidity and mortality, the effect of urban living is poorly understood. “It is important to better understand how the prevalence of hypertension varies with urbanicity because many LMICs, particularly those in Africa and Asia, are experiencing rapid urbanisation, which has health implications,” argues Cathryn Tonne, ISGlobal researcher and study’s final author.
LMICs have experienced a greater increase in non-communicable diseases, including hypertension, than high-income countries over the past three decades, and ischaemic heart disease and stroke are now among the top four causes of death in these nations.