Alzheimer's Disease Linkage to Real-World Evidence (AD-LINE) Study: Linking Claims Data to Phase 3 GRADUATE Study of...

Linking data from clinical trials and real-world claims may improve the robustness of trial data and provide information on the health, economic, and societal impacts of a disease.

To report on the feasibility of linking trial data to Medicare claims data in early symptomatic Alzheimer's disease (AD) in the US.

Alzheimer's Disease Linkage to Real-World Evidence (AD-LINE) was a noninterventional cohort study that included participants recruited from the GRADUATE program whose trial data were linked to their Medicare claims.

AD-LINE participants were 66 years and older with early symptomatic AD (ie, mild cognitive impairment [MCI] due to AD or mild AD dementia) and were enrolled in the GRADUATE program and a Medicare fee-for-service or Medicare Advantage plan.

The Centers for Medicare and Medicaid Services linked participants' clinical trial identifiers to their Medicare beneficiary identifiers using a deterministic, exact matching process. Demographics and clinical characteristics of the AD-LINE cohort at baseline were collected. Outcomes measured in this study included healthcare resource utilization derived from Medicare claims data.

In total, 147 participants across 21 US sites were invited to participate and 111 provided informed consent. Of those, 61 patients had linkable data (ie, Medicare beneficiary identifier), Medicare Parts A/B enrollment, and no health maintenance organization (HMO) enrollment in the year before trial entry. Of the 61 participants whose data were analyzed in this study, 30 had MCI due to AD and 31 had mild AD dementia. Participants in the MCI due to AD group had more healthcare resource utilization on average in the baseline period than those in the mild AD dementia group (29.9 [SD, 20.9] vs 24.5 claims [SD, 12.3]). In an ad hoc analysis, a relatively high concordance (85.3%) was seen between the rates of clinically confirmed AD diagnosis and evidence of AD diagnosis in claims data.

This linkage process may serve as a proof of concept for researchers interested in linking clinical trial and real-world claims data. The lessons learned from AD-LINE and innovation of data linkage approaches may encourage key stakeholders to link data in the future.