Netherlands study finds Lyme disease common in elderly
Lyme disease, also known as Lyme borreliosis, is a treatable condition in the elderly, but little is known about the prevalence of the illness and pervasiveness of depressive symptoms among this age group. Now, a study by Zomer and colleagues takes a more in-depth look, examining the records of patients referred to a Lyme disease center in the Netherlands between 2008 and 2014. 
by Daniel J. Cameron, MD, MPH
According to the authors, out of the 1454 patients referred to the center, 255 (17.5%) were 65 years and older, of which 45% were males. The average age was 79, with a range from 65 to 87 years.
One-third or 33% had clinical Lyme borreliosis and positive serologic tests, compared with 18% of the younger patients. Positive serology was defined as an equivocal or positive IgG ELISA in combination with an equivocal or positive IgG immunoblot.
Forty-five of the elderly patients had disseminated Lyme disease, with 5 having an active infection, writes Zomer in the European Journal of Internal Medicine.
However, when looking at symptoms of depression in this group, Zomer found “the prevalence of depressive symptoms in older patients was approximately half of that in younger patients.” According to a Beck Depression Inventory II (BDI-II) test, 9.8% of the elderly patients had depression, compared to 24.7% of the patients 18-64 years old.
The study was not designed to determine whether any of the cases were treated and their outcome. It was reassuring that doctors in the Netherlands were referring their elderly patients to the Lyme disease clinic.
- Zomer TP, van Bemmel T, van Munster B, van Kooten B, Vermeeren YM. Lyme borreliosis and depressive symptoms in patients aged 65 years and older referred to a tertiary Lyme centre. Eur J Intern Med. 2018.