A recent study presents new findings on the connection between psychiatric disorders and Lyme.
A population-based matched cohort study of 2897 patients in Denmark found Lyme neuroborreliosis is not linked to an increased risk of psychiatric disorders or hospitalizations.1 The study, published in JAMA Psychiatry, also showed psychiatric medications were dispensed within the first year after patients received a diagnosis of Lyme neuroborreliosis, but these prescribing patterns subsided a year after diagnosis. Malte M. Tetens, BMsc, of the Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, and colleagues assessed the risk of psychiatric disorders and hospitalizations (inpatient and outpatient), as well as prescription medications redeemed by patients for up to 15 years after the diagnosis of the disease.
According to Tetens, “The most important message from our study is that we did not demonstrate any increased risk of psychiatric disease.”
The study included all Danish patients in whom the presence of Lyme neuroborreliosis was detected between 1995 and 2015 with an intrathecal antibody index test for Borrelia burgdorferi sensu lato complex. They were matched by age and sex against a comparison cohort of Danish individuals without the disease.
The authors told Psychiatric Times, “We did demonstrate an increase in the redemption of anxiolytics, hypnotics and sedatives, and antidepressants among [patients with] Lyme neuroborreliosis within the first year after diagnosis. Possibly pain management might explain some of the increased receipt of this psychiatric medication.”
When asked about the ongoing debate around the role of Lyme borreliosis in the etiology or exacerbation of existing mental disorders,2 the authors said, “Our study is reassuring for the affected patients and serves as a counterweight to studies suggesting that psychiatric disease is caused by Lyme neuroborreliosis.”
A strength of the study was the robust size, but a limitation was the comparison of patient and comparison cohorts: “[A] limitation was lack of access to scores of the psychiatric diseases. However, this was partly compensated by analysis of psychiatric hospital contacts and redemption of prescribed psychiatric medicine.”
Despite these findings, there seems to be ample evidence to dispute some of the conclusions.3 In a 2018 paper by Robert C. Bransfield, MD4, clinical associate professor at Rutgers Robert Wood Johnson Medical School, stated, “There is increasing evidence and recognition that [Lyme borreliosis] causes mental symptoms . . . [with] over 400 peer-reviewed articles addressing different aspects of neuropsychiatric symptoms caused by [Lyme borreliosis].” However, the author stated: “It is recognized there is a selection bias in many of the studies discussed in this article since only the more severe cases were referred to the mental health professionals who specialized in treating LB. Also, a significant amount of this article and many of the citations are based upon clinical observations, publications, and presentations by the author. Critical appraisal and research by others to independently validate, modify or refute the author’s findings is needed to advance future research and a better understanding of the content of this article.”
Although their findings were promising, Tetens and colleagues1 cautioned against sweeping generalizations about these study results: “It is of vital importance to differentiate the results of this study from the experience of the individual patient. Nonetheless, based on our study it is reasonable to suggest that Lyme neuroborreliosis is not a major cause of psychiatric disease.”
1. Tetens MM, Haahr R, Dessau RB, et al. Assessment of the Risk of Psychiatric Disorders, Use of Psychiatric Hospitals, and Receipt of Psychiatric Medication Among Patients With Lyme Neuroborreliosis in Denmark. JAMA Psychiatry. 2020 Oct 7 [Epub ahead of print].
2. Stanek G, Wormser GP, Gray J, Strle F. Lyme borreliosis. Lancet. 2012;379(9814):461-473.
3. Bransfield RC. List of 700 Articles Citing Chronic Infection Associated with Tick-Borne Diseases Compiled by Dr. Robert Bransfield. International Lyme and Associated Disease Society. 2015. Accessed October 12, 2020. http://www.ilads.org/ilads_news/wp-content/uploads/2017/02/CLDList-ILADS.pdf
4. Bransfield RC. Neuropsychiatric Lyme Borreliosis: An Overview with a Focus on a Specialty Psychiatrist's Clinical Practice. Healthcare (Basel). 2018;6(3):104.