Background: Although Lyme Disease (LD) is the most commonly reported vector-borne illness in the US, real-world incidence of LD is poorly understood and likely underreported. Moreover, little is known about real-world treatment patterns. The objective of this study was to estimate LD incidence among commercially insured patients in the US from 2010 through 2013. A secondary objective was to describe initial LD treatment choices and time duration of therapy.
Methods: Incidence of LD was defined as presence of a non-ancillary healthcare claim with a LD diagnosis (International Classification of Diseases, Ninth Revision code 088.81) in 2010-2013 among patients in the Truven Health MarketScan® Research Databases. Incidence of LD was calculated separately for each calendar year among patients with continuous medical and pharmacy benefits for the calendar year. Patients with a diagnosis of a non-LD infection during the week before or after the LD diagnosis were excluded from the treatment patterns analysis to ensure that treatment was truly due to LD. Secondary analysis outcomes were the portion of patients receiving antibiotics within 14 days after a LD diagnosis, as well as types and duration of antibiotic use.
Results: On average, 32 million patients had continuous enrolment in each of the study calendar years. The incidence of LD was 0.68 per 1,000 person-years in 2010, increasing to 0.84 in 2011, 0.83 in 2012 and 0.96 in 2013. A sub-analysis limited to US geographic regions with known high incidence of LD showed similar results with annual incidence increasing from 2.56 per 1,000 person-years in 2010 to 3.64 in 2013. Mean age of LD patients was 42.4 years and approximately one-half (52.8%) were female, which remained consistent throughout the study years. Overall, the number of patients treated with antibiotics within 14 days of an LD diagnosis increased from 49.7% in 2010 to 54.8% in 2013. The mean duration of therapy decreased slightly from 38.5 days (standard deviation (SD)=44.1) in 2010 to 35.3 days (SD=41.6) in 2013 (p<0.001); however, the median duration of therapy was consistently 21 days for each calendar year.
Conclusion: While the
incidence of LD appears to be increasing over time, initial treatment patterns
remain largely unchanged. Results from this study will enhance understanding of
LD epidemiology and treatment.
B. H. Johnson,
M. M. Bonafede, None