The goal of this study was to determine whether the risk of ischemic stroke associated with increased left ventricular mass (LVM) is modified by physical activity (PA).
Background
Increased LVM is associated with an increased risk for stroke. Physical activity can decrease the risk of stroke and may have variable effects on LVM.
Methods
We used a case-control study design in a multiethnic population in northern Manhattan, New York, to study 394 case subjects who had a first ischemic stroke and 413 stroke-free control subjects. All subjects were interviewed and two-dimensional echocardiograms obtained to determine LVM.
Results
A sharp increase in risk of ischemic stroke was seen in the highest quartile of LVM (odds ratio [OR]: 6.14 [95% confidence interval {CI}: 3.04 to 12.38]). Thus, increased LVM was defined by the highest quartile of LVM. In multivariate analysis, the effect of increased LVM on the risk of stroke was significantly decreased by the presence of any level of PA versus no PA (OR: 1.59 [95% CI: 0.99 to 2.57] p < 0.07 vs. 3.53 [95% CI: 1.94 to 6.42] p < 0.0001). Although PA decreased the risk of stroke in all patients, the effect was stronger in subjects with increased LVM than among those without increased LVM (p = 0.033).
Conclusions
Increased LVM is associated with an increased risk of stroke, especially among sedentary patients. Physical activity decreases the risk of stroke among patients with increased LVM to a level comparable to that of patients without increased LVM. Recommending PA may be a nonpharmacologic tool to reduce the stroke risk, especially among patients with increased LVM.
Supported, in part, by grants from the National Institute of Neurological Disorders and Stroke (R0I NS 29993, R01-32525, NS 33248, T32 NS 07153). Dr. Rodriguez is a recipient of the National Institute of Neurological Disorders and Stroke Minority Supplement Grant.
