Economic Burden of Non-Cystic Fibrosis Bronchiectasis in the First Year after Diagnosis from A US Health Plan Perspective

Abstract

Recent estimates suggest the prevalence of non-cystic fibrosis bronchiectasis (NCFB) may be increasing in the US. The objective of this study was to determine the current economic burden of NCFB compared with non-NCFB controls in the first year after diagnosis within a commercially enrolled US population. A retrospective matched cross-sectional case control (1:3) study design was used. Data were derived from MarketScan(®) Commercial Claims and Encounters Database, which captures all patient-level demographic data and all medical and pharmacy claims during the period 1 January 2005 to 31 December 2009. NCFB patients were identified using ICD-9 codes 494.0 and 494.1. Individuals with medical claims for cystic fibrosis or chronic obstructive pulmonary disease were excluded. Incremental burden of NCFB was estimated for overall and respiratory-related expenditures using multivariate regression models which adjusted for baseline characteristics and healthcare resource utilization. All demographic characteristics and economic outcomes were ascertained in 12 months before (baseline period) and 12 months after (follow-up) index event, which was defined as the first bronchiectasis-related medical event. Non-parametric bootstrap technique was used to calculate the 95 % confidence limits for the adjusted estimate. All costs are inflation-adjusted to a baseline year of 2009 using the consumer price index. All statistical tests were conducted using SAS 9.2 and STATA 12.0. The study sample used for healthcare burden analyses had 9,146 cases and 27,438 matched controls. The majority of the sample was between the ages of 45-64 years old and 64 % were female. A greater proportion of cases than controls had an increase from baseline to follow-up in both total (49 vs 40 %) and respiratory-related costs (57 vs 25 %). The average increase in overall and respiratory-related costs compared with controls after adjusting for differences in baseline characteristics was US$2,319 (95 % CI 1,872-2,765) and US$1,607 (95 % CI 1,406-1,809), respectively. The primary driver for this increment was increase in outpatient visits of approximately 2 overall and 1.6 respiratory-related visits per patient per year, which translated to US$1,730 (95 % CI 1,332-2,127) and US$1,253 (95 % CI 1,097-1,408), respectively. This study found that the cost of managing NCFB in the first year within a commercially enrolled population may be burdensome. Compared with previously published estimates in the literature, the burden of NCFB may be also increasing.