April 14 (UPI) -- People fully vaccinated against COVID-19 with a history of certain psychiatric conditions are at higher risk for developing "breakthrough" cases, or infections that occur despite being inoculated, a study published Thursday found.
This may be due to an impaired immune response caused by these mental health conditions, as well as risky behaviors associated with some of them, the researchers according to an article published Thursday by JAMA Network Open.
Patients age 65 years and older with substance abuse, psychotic disorders, bipolar disorder, adjustment disorder and anxiety are up to 24% more likely to develop breakthrough COVID-19 after vaccination than those with no history of mental health problems, the data showed.
Those age 65 years and younger with these conditions are up to 11% more likely to have breakthrough cases than those who do not have a history of psychiatric disorders, the researchers said.
"Our research suggests that increased breakthrough infections in people with psychiatric disorders cannot be entirely explained by socio-demographic factors or pre-existing conditions," study co-author Aoife O'Donovan said in a press release.
"It's possible that immunity following vaccination wanes more quickly or more strongly for people with psychiatric disorders and/or they could have less protection to newer variants," said O'Donovan, an associate professor of psychiatry at the University of California-San Francisco.
A study published in February by the same UCSF researchers found that people with elevated anxiety and probable post-traumatic stress disorder, conditions associated with impulsivity, were more likely to engage in behaviors that put them at higher risk for COVID-19.
The new findings are based on a review of data from more than 263,000 U.S. Department of Veterans Affairs patients who were fully vaccinated and had been tested for COVID-19 at least once.
Just over half, 51%, had received at least one psychiatric diagnosis within the past five years and 15% developed breakthrough COVID-19, as confirmed by a positive test, the data showed.
Participants with psychiatric disorders had a 3% increased risk for breakthrough COVID-19 infections in 2021 compared with participants without a psychiatric history, the researchers said.
However, the risk was 24% higher for those age 65 years and older with substance abuse disorder, 23% higher for those with psychotic disorders such as schizophrenia, 16% higher for bipolar disorder, 14% for adjustment disorder, a disorder caused by poor stress response, and 12% higher for anxiety, they said.
In addition, the risk was 11% higher in people age 65 years and younger with substance abuse disorder, 9% higher for adjustment disorder, 4% higher for anxiety and 3% higher for post-traumatic stress disorder, according to the researchers.
This higher risk is on par with those associated with other chronic health conditions, including kidney disease, heart disease, HIV and lung disease, they said.
"Mental health is important to consider in conjunction with other risk factors," O'Donovan said.
"Some patients should be prioritized for boosters and other critical preventive efforts," she said.