Abstract
By using commercial insurance claims data, we estimated that Lyme disease was diagnosed and treated in ≈476,000 patients in the United States annually during 2010–2018. Our results underscore the need for accurate diagnosis and improved prevention.
Lyme disease is caused by
Borrelia burgdorferi spirochetes, which are transmitted to humans by certain
Ixodes spp. ticks (
1). The infection can involve multiple organ systems and is treatable with antimicrobial drugs; most persons recover fully, especially those who receive early and appropriate treatment (
1). The geographic distribution of Lyme disease in the United States and the demographic characteristics of persons affected have been well documented through nearly 3 decades of public health surveillance (
Abstract
We evaluated MarketScan, a large commercial insurance claims database, for its potential use as a stable and consistent source of information on Lyme disease diagnoses in the United States. The age, sex, and geographic composition of the enrolled population during 2010–2018 remained proportionally stable, despite fluctuations in the number of enrollees. Annual incidence of Lyme disease diagnoses per 100,000 enrollees ranged from 49 to 88, ≈6–8 times higher than that observed for cases reported through notifiable disease surveillance. Age and sex distributions among Lyme disease diagnoses in MarketScan were similar to those of cases reported through surveillance, but proportionally more diagnoses occurred outside of peak summer months, among female enrollees, and outside high-incidence states. Misdiagnoses, particularly in low-incidence states, may account for some of the observed epidemiologic differences. Commercial claims provide a stable data source to monitor tren
Our investigation has some limitations. First, interviews were conducted several weeks after illness onset, which enabled accurate classification of patients by hospitalization status and data collection on all symptoms and their duration (
45). However, this timing might result in incomplete recall and recall bias, which could affect the accuracy of reported symptoms and their timing, particularly among hospitalized patients, who might be more likely to remember more severe symptoms (
46). Future prospective studies using methods such as symptom diaries or serial interviews could reduce recall bias. Second, a higher proportion of proxies were interviewed on behalf of hospitalized case-patients. However, when proxies were removed from the reduced multivariable model, the ORs were relatively stable, indicating the proxies did not affect the association of symptoms with hospitalization. In addition, although clinical manifestation of viral respiratory diseases can differ by age, we w