One in two women and one in three men older than 45 will develop Parkinson’s disease, dementia or stroke during their lifetime, a new study suggests.
Preventive strategies to delay disease onset can reduce this risk by up to half.
The study with those findings, “Lifetime risk of common neurological diseases in the elderly population” was published in the Journal of Neurology, Neurosurgery & Psychiatry.
Parkinson’s disease, dementia and stroke are among the leading causes of mortality and disability in older individuals. In fact, the diseases often co-occur. Parkinson’s disease and stroke patients are at increased risk of dementia, and patients with dementia at increased risk of stroke.
Researchers from the University Medical Center Rotterdam, The Netherlands, assessed the lifetime risk for dementia, stroke and parkinsonism in middle-aged and elderly men and women between 1990 and 2016.
They followed 12,102 individuals (57.7% women) aged 45 or older who were free from these diseases at baseline (beginning), and enrolled in the Rotterdam Study, a prospective population-based group. Participants participated in full medical check-ups every four years.
After 26-years of follow-up, 1,489 individuals were diagnosed with dementia, 1,285 with stroke, and 263 with Parkinson’s disease. A total of 438 individuals were diagnosed with more than one disease.
The overall lifetime risk to develop any of these conditions for a 45-year-old was 48.2% in women and 36.3% in men.
This difference was due to a higher risk of dementia as the first manifesting disease in women rather than men (25.9% vs 13.7%, respectively), while the risk for stroke (19.0% vs 18.9%) and parkinsonism (3.3% vs 3.6%) was similar between the sexes.
Moreover, this risk increased with age – between the ages of 45 to 65 years this risk ranged from 2.6% for women and 3.2% for men. After that, and until the age of 95, up to 45.8% of women and 35.3% of men were at risk.
“At age 45, first manifestation of stroke posed the highest lifetime risk for men (18.9%). Dementia posed the largest risk for women (25.9%), which was significantly higher compared with that for men (13.7%),” researchers wrote.
The lifetime risk for Parkinson’s was similar between women (4.3%) and men (4.9%).
Strategies that delay disease onset between one to three years could reduce the lifetime risk for developing any of these diseases by 20% in individuals 45 and older, and by more then 50% in the oldest members of that group.
“Even a delay in onset for a few years of only one disease could already result in substantial reductions for the combined lifetime risk of developing any of these diseases,” researchers wrote.
“These findings strengthen the call for prioritizing the focus on preventive interventions at population level which could substantially reduce the burden of common neurological diseases in the aging population,” they concluded.