April 24 (UPI) -- Asthma, hay fever and eczema are linked to an increased risk of developing psychiatric disorders, according to a new study in Taiwan.
The researchers relied on a database of health insurance claims of 46,647 people with allergic diseases and 139,941 people without the ailments from 2000 to 2015. The research was published this week in the journal Frontiers in Psychiatry.
"We would like to let clinicians who care for patients with allergic diseases know that their risk for psychiatric diseases may be higher," lead author Dr. Nian-Sheng Tzeng, from Tri-Service General Hospital in Taiwan, said in a Frontiers press release. "Assessing their emotional condition and monitoring their mental health could help to avoid later psychiatric problems."
Psychiatric disorders include depression, anxiety, bipolar disorder and schizophrenia.
The most common allergic diseases are nicknamed the three "A"s: asthma, allergic rhinitis or hay fever and atopic dermatitis, also known as eczema.
"As a clinician, I observed that some patients with the three 'A's appeared to suffer emotionally," Tzeng said. "Therefore, I wanted to clarify whether these allergic diseases are associated with psychiatric disorders."
Previous research found links between allergic diseases and specific psychiatric disorders or emotional problems. And one study in Taiwan suggested allergic rhinitis is less common among patients with schizophrenia.
But no one had studied the link between the three "A"s and the overall risk of developing psychiatric disorders, the researchers said.
Over the 15-year period, 10.8 percent of people with allergic diseases developed a psychiatric disorder, compared with 6.7 percent of those with no allergic disease.
In further data analysis, researchers found people with atopic dermatitis had a lower risk of developing a psychiatric disorder than those with asthma and allergic rhinitis had a higher risk.
They also found certain asthma medication use was associated with a lower risk of psychiatric disorders in asthma patients. Oral prednisolone usage was associated with a lower risk of developing psychiatric disorders in bronchial asthma patients. Also studied were inhaled steroids, beta-agonist, aminophylline, leukotriene receptor antagonists and anti-IgE antibody medicine.
To explain the link, they said research suggests that inflammation is linked to psychiatric disorders, including depression and anxiety disorders. And because allergies also involve inflammation, it is possible that it may contribute to psychiatric disorders in the same patients.