Risk factors for symptoms of stroke in a community-based observational study in Nepal

Abstract

Background: Stroke is currently the third leading cause of death and sixth highest cause of premature death in Nepal. While studies have been conducted at tertiary care facilities to describe the epidemiology of hospitalized stroke, there has been limited research using population-level data that can reveal major risk factors for stroke in the Nepalese population. This study describes the prevalence of and risk factors for self-reported symptoms of stroke in participants of the Dhulikhel Heart Study (DHS), Dhulikhel, Nepal. Methods: We conducted analysis of cross-sectional data collected at baseline from participants enrolled in the Dhulikhel Heart Study, a population-based, longitudinal cohort study focused on investigating risk factors for cardiovascular disease in Dhulikhel, Nepal. The study included 1073 individuals aged 18 or older who were randomly sampled from residents of Dhulikhel at the household level. Participants were surveyed with a battery of instruments that included the Questionnaire for Verifying Stroke-Free Status (QVSFS), a validated questionnaire used to assess whether individuals exhibit stroke symptoms. Pearson’s chi-squared tests and t-tests were used to examine associations between demographic, physical, and behavioral risk factors stratified by sex as well as binary stroke outcome. Multivariate logistic regression models were developed hierarchically for further assessment of risk factors. Fully adjusted models included the following covariates: demographic characteristics (sex, age [categorical], ethnicity, education, annual income, employment status, marriage status), physical risk factors (BMI, hypertension, diabetes, severe chest pain lasting at least half an hour, depression), and behavioral risk factors (fruit/vegetable/fat consumption, smoking, exposure to secondhand smoke, alcohol use, physical activity, stress). Results: The mean age of study participants was 40.5 (SD=16.4) years and 58.4% were female. A total of 126 individuals in the study (11.7%) had at least one self-reported stroke symptom assessed from the QVSFS. In the fully adjusted linear regression model, females had a 2.7-fold greater odds of exhibiting stroke symptoms compared to males (p=0.003, 95% CI: 1.4, 5.2). Obesity (BMI>30) was found to be protective and associated with an odds of stroke symptoms 0.3 times that of normal weight (p=0.03, 95% CI: 0.1, 0.9), as was a high level of physical activity (>5000 MET-min per week) with an odds of stroke symptoms 0.2 times that of the lower recommended level of physical activity (p=0.001, 95% CI: 0.1, 0.5). The presence of at least one major life stressor was associated with an odds of stroke symptoms 2.1 times that of individuals with no major stressors (p=0.003, 95% CI: 1.3, 3.5). Discussion: Nepal has a unique stroke symptom profile. The prevalence of individuals who exhibited stroke symptoms in this study was twice as high as in the United States and suggests a potentially high burden of stroke in Nepal. This burden of stroke symptoms was skewed toward younger ages and females compared to the global burden. Significant risk factors for an increased risk of exhibiting stroke symptoms included sex, age, and having at least one major life stressor. Unemployment was marginally associated with higher odds of stroke symptoms. Significant protective factors included high levels of physical activity and, surprisingly, obesity. Collinearity between variables and the fact that the QVSFS has higher negative predictive value than positive predictive value may explain why traditional behavioral and metabolic risk factors were not found to be significant in this study’s fully adjusted logistic regression model. Obesity and access to foods such as fruits and fats may also have been protective due to being an indicator of increased household wealth. Conclusion: The results of this study confirm the high burden of stroke symptoms and risk factors within Nepal. Prospective longitudinal studies are needed to verify these results and monitor trends in stroke and other chronic disease risk factors to strengthen the country’s ability to prevent and respond to the growing burden of non-communicable diseases.