Summary
Patients with Post-treatment Lyme Disease Syndrome (PTLDS) commonly complain of cognitive symptoms. However, prior studies assessing neuropsychological functioning in this population have varied both in terms of patient selection criteria and the significance of their findings. This study sought to assess objective cognitive functioning status in a well-defined sample of patients with PTLDS. The study found, in subsets of PTLDS patients, objective evidence of cognitive decline in verbal memory and processing speed, cognitive impairment, and sub-optimal engagement with testing.
Why was this study done?
Patients with post-treatment Lyme disease syndrome (PTLDS) commonly complain of cognitive symptoms, however prior studies assessing neuropsychological functioning in this population have varied. This study was done to systematically examine and measure cognitive functioning of patients with PTLDS, using standardized testing instruments.
How was this study done?
The study enrolled 124 patients with confirmed PTLDS defined by the Infectious Diseases Society of America’s proposed case definition. Cognitive functioning was evaluated using standardized neuropsychological measures of attention, memory, processing speed, and test engagement.
What were the major findings?
The majority (92%) of participants with PTLDS reported symptoms of cognitive difficulty to some degree. Objective evidence of cognitive decline (compared to estimated pre-morbid function) was identified in 26% of participants, with the most robust findings in verbal memory and processing speed. A subset (22% of those with decline) also showed objective evidence of cognitive impairment compared to population-level performance. Despite subjective symptoms, 50% of the sample showed no statistically or clinically significant objective decline in cognitive function using standardized neuropsychological measures. The remaining 24% of the sample were found to have sub-optimal engagement on testing measures, which may be due to the impact of fatigue, pain, prior negative clinical experiences, or other unknown factors.
What is the impact of this work?
The current findings support objective evidence of cognitive decline and impairment in subsets of patients with PTLDS in distinct areas of cognitive functioning, especially verbal memory and processing speed. Further studies are needed to better understand the patient subjective experience of cognitive decline as well as the factors associated with objective cognitive decline to better manage symptoms of PTLDS and improve health related quality of life.
This research was supported by:
The research was supported by The Lyme Disease Research Foundation and the Steven and Alexandra Cohen Foundation.
Link to the original research article:
Cognitive Decline in Post-treatment Lyme Disease Syndrome – Pegah Touradji, John N Aucott, Ting Yang, Alison W Rebman, Kathleen T Bechtold; Cognitive Decline in Post-treatment Lyme Disease Syndrome, Archives of Clinical Neuropsychology, , acy051,
