HealthDay News — Schizophrenia spectrum disorder increases the risk for Parkinson disease (PD) later in life, according to a study published online Jan. 6 in Movement Disorders.
Tomi Kuusimäki, M.D., from Turku University Hospital in Finland, and colleagues investigated the risk for PD after a diagnosis of a schizophrenia spectrum disorder. The analysis included 3,045 patients with a confirmed PD diagnosis (2004 to 2019).
The researchers found that the prevalence of earlier schizophrenia spectrum disorder was 0.76 percent in PD patients in regional data and 1.50 percent in nationwide data, while in age-matched controls, the prevalence of schizophrenia spectrum disorder in the regional and national data was 0.16 and 1.31 percent, respectively. Following a schizophrenia diagnosis, the odds ratio for PD was 4.63 in the regional data and 1.17 in the national data.
“The occurrence of PD and schizophrenia in the same person has been considered rare because these diseases are associated with opposite alterations in the brain’s dopamine system,” Kuusimäki said in a statement. “Our study changes this prevailing conception.”