People with Lyme neuroborreliosis not at overall increased risk for psychiatric disorders

Individuals with Lyme neuroborreliosis were not at overall increased risk for psychiatric disorders, according to results of a nationwide population-based matched cohort study published in JAMA Psychiatry.

“Lyme neuroborreliosis has been associated with a variety of psychiatric conditions, including schizophrenia, mood affective disorders, suicide and anxiety,” Malte M. Tetens, BMSc, of the department of infectious diseases at Copenhagen University Hospital in Denmark, and colleagues wrote. “However, most studies of these associations have been limited by flaws in study design. To our knowledge, no nationwide population-based cohort study with long-term follow-up of the potential association between Lyme neuroborreliosis and the risk of developing psychiatric diseases has been performed.”

To address this research gap, the investigators sought to evaluate the risk for psychiatric disease, the percentage of psychiatric inpatient and outpatient contacts and prescribed psychiatric medication receipt among 2,897 individuals with Lyme neuroborreliosis vs. 28,970 in a matched comparison cohort, for all of whom the median patient age was 45.7 years. They included all residents of Denmark who tested positive for Borrelia burgdorferi according to an intrathecal antibody index test between January 1995 and December 2015 and matched cohorts by age and sex.

Results showed no increased risk for psychiatric disease diagnosis and the percentage of hospital contacts for psychiatric disease among individuals with Lyme neuroborreliosis vs. those without. However, certain prescriptions were higher among those with Lyme neuroborreliosis, including anxiolytic (difference = 2.6%; 95% CI, 1.6%-3.5%), hypnotic and sedative (difference = 2.6%; 95% CI, 1.6%-3.5%) and antidepressant (difference = 5.4%; 95% CI, 4.3%-6.6%) medications within 1 year of diagnosis, after which receipt of these medications returned to the level of that of the comparison cohort.

“The clinical implications of our study are notable in that no data were found to indicate an increase in the long-term risk [for] developing psychiatric disease after a diagnosis of Lyme neuroborreliosis,” Tetens and colleagues wrote. “However, the short-term affective symptoms of Lyme neuroborreliosis warrant further investigation to assess the association between Lyme neuroborreliosis and the receipt of prescribed psychiatric medications.”