Contrast Sensitivity Loss in Patients With Posttreatment Lyme Disease

PURPOSE: Posttreatment Lyme disease (PTLD) is marked by neurologic symptoms, cognitive impairment, and significant symptom burden, including fatigue and ocular complaints. The purpose of this study was to determine whether contrast sensitivity (CS) is altered in patients with PTLD compared with healthy controls and, second, whether CS is associated with cognitive and/or neurologic deficits. METHODS: CS was measured using a Pelli–Robson chart with forced-choice procedures, and the total number of letters read was recorded for each eye. CS impairment was defined for age <60 years as logCS of 1.80 (36 letters or fewer) and for those age ≥60 years as logCS of 1.65 (33 letters or fewer). Participants self-administered a questionnaire to assess presence of ocular symptoms and underwent a neurologic exam and battery of neurocognitive tests. RESULTS: CS impairment was associated with an increased odds of being in the PTLD group that was 2.6 times as high as those without CS impairment (odds ratio, 2.6; 95% confidence interval, 1.3–5.2). Neither cases nor controls had significant distance acuity impairment. CS impairment was not associated with any of the ocular complaints in cases but was borderline associated with neurologic abnormalities and cognitive impairment. CONCLUSIONS: CS impairment in patients with PTLD is linked to signs of cognitive and neurologic impairment and may be a marker of illness severity. TRANSLATIONAL RELEVANCE: Further investigation into the value of testing CS impairment in PTLD cases is warranted, especially if it is an indicator of cognitive or neurologic manifestations.