Risk factors for ischemic stroke; results from 9 years of follow-up in a population based cohort of Iran

Abstract

BackgroundData about the risk factors of stroke are sparse in the Middle East populations. We aimed to determine the potential risk factors and their population attributable fraction (PAF) for stroke in an Iranian population.MethodsA cohort Study consisted of 1089 men and 1289 women, with mean (SD) ages of 61.1(7.6) and 59.0(6.7) years, respectively. Cox regression was implemented to estimate the hazard ratio (HR) of each risk factor for stroke events in a stepwise method. We calculated a multivariate adjusted population attributable fraction (PAF) for any risk factors remained in the model.ResultsDuring 9.3 years of follow-up, 69 events of stroke occurred with incidence rates of 4.5 (95% CI: 3.3-6.0) and 2.5 (1.7-3.6) in 1000 person-years for men and women respectively. Among potential risk factors, only age ≥ 65 years (HR: 2.03, CI: 1.24-3.31), male gender (HR: 2.00, CI: 1.16-3.43), hypertension (HR: 3.03, CI: 1.76-5.22), diabetes mellitus (HR: 2.18, CI: 1.34-3.56), and chronic kidney disease (CKD) (HR: 2.01, CI: 1.22-3.33), were independently associated with increased risk of stroke events in the total population. A paired homogeneity test showed that the hazard ratio of CKD did not differ from other independent risk factors. The PAFs were 29.7% and 25% for male gender and age ≥ 65 as non-modifiable and 48.6%, 29.1% and 22.0% for hypertension, CKD and diabetes as modifiable risk factors respectively.ConclusionFollowing this population based study of Iranians, we demonstrated that among modifiable risk factors, CKD as well as hypertension and diabetes are the strongest independent predictors of stroke.

The impact of smoking status on 9.3 years incidence of cardiovascular and all-cause mortality among Iranian men

“…Also, it has been reported that, among smokers, the effect of risk factor accumulation on the incidence of CVD was more apparent (Iso et al, 2007). Recently, we showed that smoking had a significant risk for stroke events and had a population attributable fraction of $13% among the Iranian population (Fahimfar et al, 2012). However, no data was available on the effect of smoking on mortality and CVD events in Iran.…”

Hypertension, alcohol drinking and stroke incidence

“…A cohort study of Iran [16] found that hypertension (hazard ratio 3.03, 95% CI 1.76-5.22) was independently associated with an increased risk of stroke events in the total population. A meta-analysis also found a continuous and graded relationship between blood pressure and stroke risk in many populations, with higher levels of blood pressure conferring greater risks of stroke in hypertensive and normotensive individuals [17].…”

Study of Symptoms, Risk Factors and Prescribing Patterns in Cerebral Stroke Patients

“…It is a major cause of mortality worldwide. 2,7,19 It is the leading cause of death only next to cancer. 11,29,33 There are three types of strokes, which include Ischemic (88%) Hemorrhagic (12%) and Transient (rare type).…”