Half of women and a third of men will be diagnosed with stroke, dementia or parkinsonism in their lifetime, according to a nearly three-decades-long study of neurological disease in the Dutch population. Up to 50 percent of those cases, though, might be mitigated with early prevention.
Corresponding author M. Arfan Ikram, of Erasmus MC University Medical Center Rotterdam in the Netherlands, and colleagues said in the BMJ Journal of Neurology, Neurosurgery & Psychiatry that dementia, stroke and parkinsonism pose “a huge burden” to the elderly community.
“These common neurological diseases share many risk factors and subsequently tend to show substantial co-occurrence, with stroke and parkinsonism patients at increased risk of dementia and patients with dementia at increased risk of stroke,” Ikram and coauthors wrote. “Recent estimates indicate that the global costs-of-illness for these diseases sum up to more than 2 percent of the annual world gross domestic product.”
Despite that, the authors said informative risk estimates, public awareness campaigns and clinical studies have centered more around heart disease and cancer than neurological conditions. We can definitively say one in eight women are likely to develop breast cancer and a quarter of people will be diagnosed with heart disease, but no such numbers exist for conditions like stroke and Parkinson’s.
Ikram et al. studied 12,102 men and women aged 45 and up for their study, which aimed to quantify the prevalence of common neurological diseases in the Rotterdam Study cohort. Patients were followed for 26 years, during which time 1,489 were diagnosed with dementia, 1,285 were diagnosed with stroke and 263 with parkinsonism. Nearly 5,300 patients passed away before the study’s end, 61 percent of whom died free of disease.
Those who did develop a neurological condition were 10.1 percent more likely to be hypertensive, 3.5 percent more likely to have atrial fibrillation and 13.5 percent more likely to be diagnosed with hypercholesterolemia, according to the results. Patients with dementia, stroke or parkinsonism were also more likely to present with type 2 diabetes.
Almost 15 percent of patients who were diagnosed with a neurological disease were identified as having two or more conditions—something that was much more common in women. Female patients, according to the study, were twice as likely as men to experience both stroke and dementia during their lifetime.
Ikram and colleagues said there are limited options for preventing neurological complications as people age, but the team found preventive strategies that delay disease onset by up to three years could reduce a person’s lifetime risk for stroke, dementia and parkinsonism by 20 to 50 percent.
“There are currently no disease-modifying drugs available for dementia and most causes of parkinsonism, and prevention of stroke is hampered by suboptimal adherence to effective preventive strategies or unmet guideline thresholds,” the authors wrote. “Yet, a delay in onset of these common neurological diseases by merely a few years could reduce the population burden of these diseases substantially. In fact, preventive interventions may also contribute to a drop in competing mortality by affecting lifetime risk of diseases with similar risk factors.”
Ikram et al. said their results could be expanded in the future by considering other common diseases, like multiple sclerosis and polyneuropathy, in the older demographic. For now, the team suggested using the data to develop more effective preventive treatments.
“These results...have implications for the type of prevention strategies to develop, including population-wide interventions targeted at risk factors with considerable sex-specific differences in attributable risk, such as loneliness and depression in women or diet in men,” they wrote.