Individuals with asthma demonstrated an increased risk for Parkinson’s disease later in life, according to study results.
Researchers also reported a dose-dependent relationship between greater asthma severity and higher risk for Parkinson’s disease.
Chih-Ming Cheng, MD, of the department of psychiatry at Taipei Veterans General Hospital in Taipei, Taiwan, and colleagues used the Taiwan National Health Insurance Research Database to identify 10,455 adults aged 45 years or older diagnosed with asthma between 1998 and 2008.
Researchers compared those study participants with 41,820 controls matched for age and sex.
Follow-up continued until the end of 2011. At that time, researchers recorded asthma severity among study participants and also identified those who developed Parkinson’s disease during the follow-up period.
After adjustments for health system use, comorbidities, medication use and demographics, results showed individuals with asthma were three times more likely than controls to develop Parkinson’s disease (HR = 3.1; 95% CI, 2.2-4.36).
The elevated risk persisted after researchers performed sensitivity tests and excluded observations made during the first year of follow-up (HR = 2.9; 95% CI, 2.04-4.13) and the first 3 years of follow-up (HR = 2.46; 95% CI, 1.64-3.69).
Researchers observed elevated risks for Parkinson’s disease among study participants who developed asthma prior to age 65 years (HR = 3.51; 95% CI, 19.5-6.31) and those who developed asthma when they were aged 65 years or older (HR = 2.95; 95% CI, 1.93-4.5).
Asthma severity — determined by the annual frequency of asthma clinic visits or admissions — also appeared associated with an elevated risk for Parkinson’s disease later in life. Researchers reported HRs of 2.92 (95% CI, 1.91-4.49) for those with zero or one visits or admissions; 12.69 (95% CI, 5.03-31.71) for those with one or two visits/admissions; 16.42 (95% CI, 5.88-45.91) for those with more than two visits/admissions; and 18.88 (95% CI, 9.44-37.79) for those with more than 10 visits/admissions.
“Both middle-aged and elderly adults with asthma had an elevated risk of developing Parkinson’s disease later in life,” Cheng and colleagues wrote. “Further study is required to validate our findings and investigate the pathophysiology underlying the relationship between asthma and Parkinson’s disease.” – by Jeff Craven
Disclosure: The researchers report no relevant financial disclosures.