Stroke Rates Have Dropped 40% for People 65+
A new analysis of data from 1988-2008 by researchers at the University of California San Francisco School of Medicine has revealed a 40% decrease in the incidence of stroke in Medicare patients 65 years of age and older. The decline is greater than anticipated considering this population’s risk factors for stroke. Not only that, but the drop applies to both ischemic and hemorrhagic strokes. The team also found that deaths resulting from stroke declined during the same period. The findings are published in the July 2014 issue of The American Journal of Medicine.
A release from the publisher notes that stroke is the fourth leading cause of mortality in the United States, with approximately 795,000 strokes occurring each year. Beyond the impact on patients, treatment and after care place high demands on doctors and health care facilities. With an aging population reaching Medicare age, deconstructing and studying stroke statistics are important for understanding the causes underlying this downward trend, benefiting both patients and providers.
The release quotes lead investigator Margaret C. Fang, MD, MPH as saying, “Shedding light on trends in the burden of stroke among Medicare beneficiaries may provide important information for policy purposes, including describing the past and current scope of the condition, assessing the potential effect of stroke prevention interventions on a national level, and identifying areas where resources can be targeted more specifically and effectively.”
The study was constructed to analyze stroke cases over the past two decades, not to investigate causation; however, researchers did find evolving patterns in the risk factors associated with strokes. Although the prevalence of diabetes mellitus increased over time, other risk factors, such as cigarette smoking, measured systolic blood pressure, and total cholesterol values, decreased.
The decline in stroke rates paralleled increasing use of antihypertensive and statin medications and might explain the reduction in stroke rates. “Antihypertensive medications reduce the risk of stroke by approximately 32% and statins by approximately 21%. Stroke rates seem to decrease most sharply after year 1998, approximately when statin use became more prevalent,” explains Dr. Fang. “If true, then this illustrates how medical interventions have resulted in significant improvements in health on a population level.”
Investigators analyzed occurrence data from a sample of Medicare patients diagnosed as having suffered a stroke. Risk factors such as high blood pressure, diabetes, smoking status, and high lipid levels were gathered from the National Health and Nutrition Examination Survey (NHANES). The Medicare Current Beneficiary Survey was used to determine medication use.