Stroke trends

Two recently published studies on stroke attest to the gains made in controlling hypertension and reducing stroke risk factors—at least in older Americans.

JAMA and American Journal of Medicine each featured research on the incidence of stroke, with the former looking at enrollees in the Atherosclerosis Risk in Communities (ARIC) population and the latter at data from the National Health and Nutrition Examination Survey and the Medicare Current Beneficiary Survey. Both studies reported a decline in the rate of strokes over time.

Not just a decline, by the way, but a significant drop in the incidence rate in the 65 years and older population. The American Journal of Medicine study found a reduction of 40 percent over two decades. The JAMA research, which was based on four communities, noted similar declines in men and women and in whites and blacks. The incidence rate fell from 3.73 per 1,000 person years for total stroke to 0.93 per 1,000 person years.

Both studies placed the likely credit on preventive care, including the increased use of antihypertensive and statin medications as well as lifestyle changes. In the ARIC population, for instance, they found use of cholesterol medication was five times higher at nine-year follow-up and the proportion of smokers had dropped 14.7 percent. In the other study, statin use jumped from 4 percent in 1992 to 41.4 percent in 2008, while antihypertensive use increased from 53 percent to 73.5 percent.

But the improvement noted in elderly Americans may not carry through to younger generations. In the JAMA study, participants 65 years and older had an absolute decrease of 1.35 per 1,000 person years and those younger than 65 years a decrease of 0.09 per 1,000 person years.

This raises concerns, given stroke’s high societal and economic costs. It may be worth exploring whether lifestyle factors or increasing prevalence in obesity, diabetes and other conditions play a role in this trend.

In the meantime, cardiologists and the preventive care community deserve accolades for persevering over the years to help whittle down stroke rates in the U.S.

Candace Stuart

Cardiovascular Business, editor