Asthma linked to increased risk of Parkinson's disease

(HealthDay)—Patients with asthma may have an increased risk of developing Parkinson's disease, according to a study published online Aug. 27 in Allergy.

Chih-Ming Cheng, M.D., from the Taipei Veterans General Hospital in Taiwan, and colleagues examined the temporal association between asthma and Parkinson's disease. A cohort of 10,455 patients (age 45 years and older) who were diagnosed with asthma between 1998 and 2008 and 41,820 age- and sex-matched controls were selected and observed through 2011.

The researchers found that the risk of developing Parkinson's disease was increased among patients with asthma (hazard ratio, 3.10) after adjustment for demographic data, health system use, medical comorbidities, and medication use. After excluding observations on the first year and first three years, sensitivity tests yielded consistent findings (hazard ratios, 2.90 and 2.46, respectively). The risk of subsequent Parkinson's disease was greater for patients with asthma who had more frequent admissions during the follow-up period (hazard ratios, 16.42, 12.69, and 2.92 for more than two, one to two, and zero to one admissions, respectively).

"Patients with asthma had an elevated risk of developing Parkinson's disease later in life, and we observed a dose-dependent relationship between greater asthma severity and a higher risk of subsequent Parkinson's disease," the authors write.