Long-term survival after stroke in Lithuania: Data from Kaunas population-based stroke registry

Background
There is a lack of reliable epidemiological data on long-term survival trends of first-ever stroke patients in Lithuanian population.
Aims
To evaluate trends in long-term survival after stroke and to determine the influence of some sociodemographic and lifestyle factors, time and subtype of stroke, and stroke care on survival.
Methods
All stroke events included in Kaunas stroke register database were ascertained and validated according to the standardized criteria outlined by the WHO MONICA Project. The study included all patients in Kaunas (Lithuania) city aged 25 to 64 years who experienced a stroke between 1986 and 2011. Death time was confirmed by the Office for National Death Statistics. Estimates of stroke long-term survival data and factors influencing survival changes were made by applying the Kaplan-Meier and Cox regression analysis.
Results
During the study period, 4,129 persons aged 25–64 years suffered from a first-ever stroke: 2,215 (53.6%) of them were men and 1,914 (46.4%)—women. Ischemic stroke was significantly more frequent in males than in females (80.6% and 78.6%, respectively, p<0.05) and subarachnoid hemorrhage was more common in women than in men (9.0% and 7.0% respectively, p <0.05). Of all first-ever stroke patients, 3,272 (79.2%) survived 1 year and 2,905 (70.4%) survived 5 years after stroke onset. The 1- and 5-years survival rate after a first-ever stroke in women was significantly higher as compared with that in men (Log-rank test p = 0.0001). The older (55–64 year) persons had poorer 1-year and 5-years survival rate as compared with persons in the younger (25–54 years) age group (Log-rank test p = 0.0001). Among persons with a first-ever stroke who had their stroke in 2007–2011, 1- and 5-year survival rate was higher compared with that in persons who had had a stroke in 1986–1990 and in 1997–2001 (Log-rank test p = 0.0001). The persons with a first-ever ischemic stroke had a better chance to survive first 1- and 5-years after stroke compared with persons who had intracerebral or subarachnoid haemorrhage. Only female gender was associated with higher 1- and 5-year survival rate after first-ever stroke. The older age, previous myocardial infarction and diabetes mellitus were associated with lower 1- and 5-year survival rate after first-ever stroke.
Conclusions
This population-based study of patients with first-ever stroke demonstrated that the long-term survival was better in women than men, and improved significantly in both men and women during the past decade. Long-term survival was better of those with first-ever ischemic stroke and of younger age– 25 to 54 years.

研究背景
目前立陶宛人群中首次卒中患者长期生存趋势的可靠流行病学数据仍存在空白。
研究目的
旨在评估卒中后长期生存趋势，并明确部分社会人口学与生活方式因素、卒中发生时间与分型以及卒中救治对患者生存情况的影响。
研究方法
本研究纳入考纳斯卒中登记数据库中的所有卒中事件，并依据世界卫生组织莫尼卡项目（WHO MONICA Project）制定的标准化标准对其进行确认与验证。研究对象为1986年至2011年间罹患卒中的立陶宛考纳斯市25~64岁所有患者。患者死亡时间经国家死亡统计办公室（Office for National Death Statistics）确认。采用卡普兰-迈耶法（Kaplan-Meier）与Cox比例风险回归分析（Cox regression analysis）对卒中长期生存数据及影响生存变化的因素进行估算。
研究结果
研究期间，共计4129名25~64岁的患者发生首次卒中，其中男性2215例（占比53.6%），女性1914例（占比46.4%）。男性缺血性卒中（ischemic stroke）发生率显著高于女性（分别为80.6%与78.6%，p<0.05）；而女性蛛网膜下腔出血（subarachnoid hemorrhage）发生率高于男性（分别为9.0%与7.0%，p<0.05）。所有首次卒中患者中，3272例（79.2%）在卒中发病后存活1年，2905例（70.4%）存活5年。女性首次卒中后1年及5年生存率显著高于男性（对数秩检验（Log-rank test），p=0.0001）。55~64岁老年患者的1年及5年生存率显著低于25~54岁年轻患者（对数秩检验（Log-rank test），p=0.0001）。2007~2011年发生首次卒中的患者，其1年及5年生存率显著高于1986~1990年及1997~2001年卒中患者（对数秩检验（Log-rank test），p=0.0001）。首次发生缺血性卒中的患者，其卒中后1年及5年生存几率显著高于脑出血（intracerebral hemorrhage）或蛛网膜下腔出血患者。仅女性性别与首次卒中后更高的1年及5年生存率相关。高龄、既往心肌梗死（myocardial infarction）病史以及糖尿病（diabetes mellitus）与首次卒中后更低的1年及5年生存率相关。
研究结论
这项基于人群的首次卒中患者研究显示，女性长期生存率优于男性，且在过去十年间，男女患者的长期生存率均得到显著改善。首次发生缺血性卒中以及25~54岁的年轻患者，其长期生存率更佳。