Background: We have shown previously that extended intravenous antibiotic therapy is associated with low morbidity and no mortality in patients referred for treatment of neurologic Lyme disease. In this study, we evaluated the benefit of extended intravenous antibiotic therapy in patients with symptoms of neurologic Lyme disease.
Methods: Patients with significant neurologic symptoms and positive testing for Borrelia burgdorferi were treated with intravenous antibiotics, and biweekly evaluation of symptom severity was performed using a six-level ordinal scale. Four symptoms were selected a priori as primary outcome measures in the study, ie, fatigue, cognition, myalgias, and arthralgias. Patients were placed into five groups according to time on treatment (1-4, 5-8, 9-12, 13-24, and 25-52 weeks), and changes in the primary symptoms as a function of time on treatment were analyzed using a mixed-effects proportional odds model.
Results: Among 158 patients with more than one follow-up visit who were monitored for up to 1 year, there were on average 6.7 visits per person (median 5, range 2-24). The last follow-up day was on average 96 days after enrollment (median 69, range 7-354 days), corresponding to the length of antibiotic therapy. Each primary symptom was significantly improved at one or more time points during the study. For cognition, fatigue, and myalgias, the greatest improvement occurred in patients on the longest courses of treatment (25-52 weeks) with odds ratios (OR) for improvement of 1.97 (P = 0.02), 2.22 (P < 0.01), and 2.08 (P = 0.01), respectively. In contrast, arthralgias were only significantly improved during the initial 1-4 weeks of therapy (OR: 1.57, P = 0.04), and the beneficial effect of longer treatment did not reach statistical significance for this symptom.
Conclusion: Prolonged intravenous antibiotic therapy is associated with improved cognition, fatigue, and myalgias in patients referred for treatment of neurologic Lyme disease. Treatment for 25-52 weeks may be necessary to obtain symptomatic improvement in these patients.
Keywords: Borrelia burgdorferi; Lyme disease; intravenous antibiotics; neurologic symptoms.