LEVERAGING MEDICARE CLAIMS TO CHARACTERIZE DIAGNOSTIC PATHWAYS IN ALZHEIMER’S DISEASE

Abstract

Real-world, administrative claims data is uniquely suited to help characterize the journey of Alzheimer's disease (AD) patients from the onset of disease symptoms through diagnosis and beyond. The primary aims of this analysis were to: (1) characterize the temporal relationship between diagnostic and treatment codes associated with AD; and (2) explore the pre-diagnostic claims record for the appearance of codes suggestive of AD-related symptoms. Medical and pharmacy claims data from a large, geographically diverse, commercial, US Medicare Advantage health plan, for the period 2009–2014, was used to identify cases of newly diagnosed AD. Beneficiaries with claims for AD-specific diagnostic codes and prescription fills for a medication indicated to treat AD were included in the analysis. Among the 4,039 beneficiaries identified for inclusion in the analysis: 31% received a treatment prior to their first Alzheimer's-specific diagnostic code, 14% received an AD diagnostic code prior to their first treatment; and 23% received their treatment and diagnostic codes within 60 days of one another. Thirty-percent of the diagnosed cohort had multiple diagnostic codes but no evidence of treatment at any time during the 48-month observation period (24 months prior to and after incident diagnosis). Notable gaps between treatment and diagnosis were observed. The median number of days between treatment and diagnosis among those receiving a treatment first was 577; the median number of days between diagnosis and treatment in those receiving a diagnosis first was 397. Sixty-three percent of the combined cohort had an average of 6.1 claims suggestive of AD-related symptoms (e.g. memory loss, mild cognitive impairment) before their incident diagnostic code. These data suggests there is considerable heterogeneity in the AD diagnostic and treatment pathways. While the first appearance of a diagnosis code is commonly used as the index date from which disease related health care use is attributed, measurable care-seeking behavior and therapy associated with AD begins much earlier. Further research is needed to better understand the factors influencing pathway variability and the risks associated with diagnostic and treatment delays.