Prevalence of stroke and associated risk factors: a population-based cross-sectional study from the Qinghai-Tibet Plateau of China

Background and objectivesThe epidemiology of stroke at high altitudes has not been extensively studied, especially at heights of 4000m and above. Thus, stroke prevention and treatment at high altitudes are challenging. We conducted a cross-sectional study to estimate the prevalence of stroke, the detection rate of individuals at high risk of stroke and the risk factors for stroke in the Qinghai-Tibet Plateau in China, a high altitude plateau that inhabits approximately 15 million people. DesignA population-based cross-sectional study in the Qinghai-Tibet Plateau. SettingData were collected from participants through face-to-face screening using a primary screening table. The table relied on the China National Stroke Screening and Prevention Project. ParticipantsA total of 10700 residents aged >= 40 years and living on the Qinghai-Tibet Plateau for more than 6months participated from January 2019 to December 2021. Main outcome measuresThe primary screening table included basic demographic information, medical history information, personal lifestyle habits and physical examination information.ResultsA total of 10056 people were included in the analysis. The prevalence of stroke was 2.3% (95% CI 2.0% to 2.6%), and the detection rate of individuals at high risk of stroke was 26.2% (95% CI 25.3% to 27.0%). The prevalence of stroke and the detection rate of individuals at high risk of stroke increased with altitude (p<0.01), and the prevalence of stroke at high altitudes was almost 2.2 times that at mid-altitudes (p<0.01). After full adjustments, age, residence, hypertension, family history of stroke and smoking were significantly associated with stroke (p<0.05). ConclusionsThe prevalence of stroke, the related risk factors and the detection rate of high-risk individuals were clarified. The prevalence rates of hypertension, overweight or obesity and diabetes in the Qinghai-Tibet Plateau were all higher than the Chinese average. Higher-altitude exposure may be an independent risk factor for stroke.