Lazo-Porras Maria, Bernabe-Ortiz Antonio, Gilman Robert H, Checkley William, Smeeth Liam, Miranda J Jaime
CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima, Peru.
Division of Tropical and Humanitarian Medicine, Geneva University Hospitals & University of Geneva, Switzerland.
Lancet Reg Health Am. 2022 Jan;5. doi: 10.1016/j.lana.2021.100083. Epub 2021 Oct 30.
Limited information exists about the incidence of first-ever stroke at the population level, particularly in low- and middle-income countries (LMIC). Longitudinal data from the CRONICAS Cohort Study includes both altitude and urbanization and allows a detailed assessment of stroke incidence in resource constrained settings. The aim of this study was to estimate the incidence and explore risk factors of first-ever stroke at the population level in Peru.
Stroke was defined using a standardised approach based on information from cohort participants or family members. This information was adjudicated centrally by trained physicians using common definitions. Time of follow-up was calculated as the difference between date of enrolment and the reported date of the stroke event. Unstandardised and age-standardised, first-ever stroke incidence rate and 95% confidence intervals (95% CI) were calculated. Generalized linear models, assuming Poisson distribution and link log, were utilized to determine potential factors to develop stroke.
3,601 individuals were originally enrolled in the cohort and 2,471 provided data for the longitudinal analysis. The median time of follow-up was 7.0 (range: 1 - 9) years, accruing a total of 17,308 person-years. During followup, there were 25 incident cases of stroke, resulting in an age-standardised incidence of stroke of 98.8 (95% CI: 63.8 - 154.0) per 100,000 person-years. After adjustment by age and sex, stroke incidence was higher among people with hypertension (incidence risk ratio (IRR) = 5.18; 95% CI: 1.89 - 14.16), but lower among people living at high altitude (IRR = 0.09; 95% CI: 0.01 - 0.63).
Our results indicate a high incidence of first-ever strokes in Peruvian general population. These results are consistent with the estimates found in previous LMIC reports. Our study also found a contributing role of hypertension, increasing the risk of having a first-ever stroke. This work further advances the field of stroke epidemiology by identifying high altitude as a factor related to lower incidence of stroke in a longitudinal study. However, this information needs to be considered with cautions because of the study limitations.
在人群层面，关于首次中风发病率的信息有限，尤其是在低收入和中等收入国家（LMIC）。CRONICAS队列研究的纵向数据涵盖了海拔和城市化情况，能够对资源受限环境中的中风发病率进行详细评估。本研究的目的是估计秘鲁人群中首次中风的发病率并探索其风险因素。
中风的定义采用基于队列参与者或家庭成员信息的标准化方法。这些信息由经过培训的医生根据通用定义进行集中判定。随访时间计算为入组日期与报告的中风事件日期之间的差值。计算了未标准化和年龄标准化的首次中风发病率及95%置信区间（95%CI）。采用假设泊松分布和对数链接的广义线性模型来确定发生中风的潜在因素。
最初有3601人纳入该队列，2471人提供了用于纵向分析的数据。随访时间中位数为7.0（范围：1 - 9）年，总计17308人年。随访期间，有25例中风病例，年龄标准化中风发病率为每10万人年98.8（95%CI：63.8 - 154.0）。在按年龄和性别调整后，高血压患者的中风发病率较高（发病风险比（IRR）= 5.18；95%CI：1.89 - 14.16），但生活在高海拔地区的人群中风发病率较低（IRR = 0.09；95%CI：0.01 - 0.63）。
我们的结果表明秘鲁普通人群中首次中风的发病率较高。这些结果与先前低收入和中等收入国家报告中的估计一致。我们的研究还发现高血压起到了一定作用，增加了首次中风的风险。这项工作通过在纵向研究中确定高海拔是与中风发病率较低相关的一个因素，进一步推动了中风流行病学领域的发展。然而，由于研究存在局限性，对这些信息需谨慎考虑。
