Long term clinical outcomes of patients with ischemic stroke in primary care - a 9-year retrospective study

Background We aim to document the long-term outcomes of ischemic stroke patients and explore the potential risk factors for recurrent cardiovascular events and all-cause mortality in primary care. Methods A retrospective cohort study performed at two general out-patient clinics (GOPCs) under Hospital Authority (HA) in Hong Kong (HK). Ischemic stroke patients with at least two consecutive follow-up visits during the recruitment period (1/1-30/6/2010) were included. Patients were followed up regularly till the date of recurrent stroke, cardiovascular event, death or 31/12/2018. The primary outcome was the occurrence of recurrent cerebrovascular event including transient ischemic stroke (TIA), ischemic stroke or hemorrhagic stroke. The secondary outcomes were all-cause mortality and coronary artery disease (CAD). We fit cox proportional hazard model adjusting death as competing risk factor to estimate the cause-specific hazard ratio (csHR). Results A total of 466 patients (mean age, 71.5 years) were included. During a median follow-up period of 8.7 years, 158 patients (33.9%) died. Eighty patients (17.2%) had recurrent stroke and 57 (12.2%) patients developed CAD. Age was an independent risk factor for recurrent stroke, CAD and death. Statin therapy at baseline had a protective effect for recurrent stroke (csHR = 0.476; 95% confidence interval [CI] 0.285-0.796, P = 0.005) after adjusting death as a competing risk factor and all-cause mortality (HR = 0.693, 95% CI 0.486-0.968, P = 0.043). In addition, female sex, antiplatelet and a higher diastolic blood pressure (DBP) at baseline were also independent predictors for survival. Conclusions Long term prognosis of ischemic stroke patients in primary care is favorable. Use of statin was associated with a significant decrease in stroke recurrence and mortality. Patients who died had a significant lower DBP at baseline, highlighted the need to consider both systolic and diastolic blood pressure in our daily practice.