Lyme disease and psychiatric disorders
Confirmed cases of Lyme disease – an infection by Borrelia spp. acquired from a tick bite – are becoming more common in the UK. Although easily treatable if recognised early, the infection may have serious complications and, in 2% – 4% of individuals infected, it causes neuroborreliosis – a syndrome including meningoradiculoneuritis, encephalitis, myelitis and zoster-like pain (Dtsch Arztebl Int 2018;115:751–756). Researchers in Denmark have explored the possibility that neuroborreliosis may, in turn, be associated with psychiatric disorders.
The case-control study included all Danish residents with an intrathecal antibody index test for Borrelia burgdorferi between 1995 and 2015 (n=2,897); they were matched by age and sex to 28,970 population controls.
There was no difference between the cases and controls in the risk of a psychiatric disease diagnosis or hospital contacts for psychiatric disease. More patients with Lyme neuroborreliosis were prescribed psychotropic drug within the first year after diagnosis: 7.2% vs 4.7% for anxiolytics; 11% vs 5.3% for hypnotics and sedatives; and 11% vs 6.0% for antidepressants. However, after that period there was no difference in prescribed medication between the groups, suggesting the symptoms subside within a year.