The consequences of overdiagnosis and overtreatment of Lyme disease: An observational study

Background: The adverse consequences associated with overdiagnosis and overtreatment of Lyme disease, although previously recognized, have received inadequate attention. Objective: To determine the use of health services and occurrence of treatment-related illness, disability, and distress among patients in whom Lyme disease is inappropriately diagnosed or treated. Design: Observational cohort study. Setting: University-based Lyme disease clinic. Participants: 209 patients with a presumptive diagnosis of Lyme disease previously assigned by referring physicians, the patients themselves, or both. Measurements: Self-reported data, review of medical records, and standardized instruments were used to determine 1) use of health services in terms of number of outpatient visits, number of physicians seen, types of serologic tests, and days of antibiotic treatment; 2) occurrence of antibiotic-related adverse events; and 3) levels of disability, depression, and stress. Results: Of the 209 patients, 44 (21%) met criteria for active Lyme disease, 40 (19%) had previous but not active Lyme disease, and 125 (60%) had no evidence of current or previous infection. In general, patients with active Lyme disease (who were not the focus of this study) had good outcomes. Patients with previous Lyme disease and patients with no evidence of Lyme disease used considerable health resources (median number of office visits, 11 and 7; median number of serologic tests, 4 and 4; and median days of antibiotic treatment, 75 and 42), had frequent minor adverse drug events (53% and 55%), reported significant disability (proportion of symptomatic days during which normal activities could not be performed, 16% and 18%), and had high rates of depression (38% and 42%) and stress (52% and 45%). Conclusions: Overdiagnosis and overtreatment of Lyme disease are associated with inappropriate use of health services, avoidable treatment-related illness, and substantial disability and distress.