Parkinson’s disease is the second most common neurodegenerative disorder among people older than 65 years of age. The incidence of the disease rises steeply with age, and symptoms include bradykinesia, resting tremor, gait imbalance, muscular rigidity, postural instability, slowing of physical movements, and autonomic dysfunction, which are caused by a progressive degeneration and loss of dopaminergic cells in the substantia nigra.
Evidence from previous studies supports an association between allergic diseases and related chronic inflammatory process and the development of neurodegenerative disorders, such as Alzheimer’s disease. However, there is a lack of research concerning the relationship between allergic diseases and Parkinson’s disease.
In the study entitled “Risk of developing Parkinson’s disease among patients with asthma: a nationwide longitudinal study,” 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 (NHIRD), a large sample size, and a longitudinal follow-up study design to investigate the temporal association between asthma and the risk of subsequent Parkinson’s disease.
A total of 10,455 patients who were diagnosed with asthma between 1998 and 2008 and aged ≥45 years and 41,820 age- and sex-matched controls took part in the study and were followed until 2011. The researchers identified those who developed Parkinson’s disease during the follow-up period and examined their asthma severity, as indicated by the frequency of admission (times per year) for asthma exacerbation, and the risk of subsequent Parkinson’s disease.
The results revealed that patients with asthma had an increased risk of developing Parkinson’s disease even after the researchers adjusted for demographic data, health system use, medical comorbidities, and medication use.
The researchers also found that patients with asthma who had more frequent admissions (times per year) during the follow-up period exhibited a greater risk of subsequent Parkinson’s disease.
“Both middle-aged and elderly adults with asthma had an elevated risk of developing Parkinson’s disease later in life,” Cheng and colleagues wrote according to a news release. “Further study is required to validate our findings and investigate the pathophysiology underlying the relationship between asthma and Parkinson’s disease.”