Parkinson's Disease Relatives at Risk for Dementia
Younger age at onset of Parkinson's disease raises odds
FRIDAY, Oct. 12 (HealthDay News) -- Relatives of patients with Parkinson's disease are at increased risk of cognitive impairment or dementia, and the two diseases may share familial susceptibility, according to the results of a study published in the October issue of the Archives of Neurology.
Walter A. Rocca, M.D., of the Mayo Clinic College of Medicine in Rochester, Minn., and colleagues conducted a study of 1,019 first-degree relatives of 162 patients with Parkinson's disease, as well as 858 relatives of 147 matched controls. A further 2,716 first-degree relatives of 411 Parkinson's disease patients were also studied.
Relatives of Parkinson's disease patients were at 1.37 times higher risk for cognitive impairment or dementia than the relatives of the control subjects. The relatives of those whose Parkinson's disease began before the age of 66 were at greater risk than those whose relatives developed the disease at a later age.
"In this population-based sample, the risk of cognitive impairment or dementia was modestly increased overall but was sizably increased for relatives of patients with younger age at onset of Parkinson's disease," the authors write. "The observed associations suggest the action of shared familial susceptibility factors, genetic or non-genetic."