# Amyloid PET and changes in clinical management among ethnoracially diverse and clinically atypical individuals: Findings from New IDEAS

## TL;DR

This study shows that amyloid PET scans lead to changes in how doctors manage patients with cognitive issues, including diverse ethnic groups and those with atypical Alzheimer's symptoms.

## Contribution

The study provides evidence of amyloid PET's impact on clinical decisions in diverse and atypical Alzheimer's populations previously underrepresented in research.

## Key findings

- Amyloid PET scans led to clinical management changes in over 50% of Black/African American and Hispanic/Latino participants.
- Participants with atypical Alzheimer's presentations also experienced significant changes in management after amyloid PET scans.
- Black/African American participants with positive amyloid PET results had a higher likelihood of management changes.

## Abstract

Amyloid PET use has been associated with change in clinical management among cognitively impaired older adults but various ethnoracial groups were underrepresented in prior studies. New IDEAS examined whether this association exists among cognitively impaired ethnoracially diverse Medicare beneficiaries and beneficiaries presenting with clinically “atypical” (non‐memory predominant) presentations of Alzheimer's disease (AD).

New IDEAS was a national, multi‐site, prospective, longitudinal study that enrolled Medicare beneficiaries with mild cognitive impairment (MCI) or dementia who underwent amyloid PET scan as recommended by their treating dementia specialists at “real‐world” clinics. The study examined association between amyloid PET and subsequent change in clinical management within 90 days of PET.

Primary endpoint was change in management between pre‐ and post‐PET visits defined as a composite inclusive of change in AD and non‐AD drugs and change in counseling about safety and future planning. Proportions of change in management between pre‐ and post‐PET visit by group are reported as well as logistic regression examining association between composite change in management and multiple factors.

Median age of 4363 participants is 75 (range 35‐98) years and 55.4% are female, 63.8% having MCI and 65.4% (95% CI 64.0, 66.8) amyloid PET positive. The sample includes 938 (21.5%) Black/African American, 707 (16.2%) Hispanic/Latino, and 2718 (62.3%) other individuals with 1330 (30.5%) participants with atypical presentations of AD (Table 1).

Overall change in management occurred in 54.7% (95% CI 51.5, 57.9) of Black/African American, 53.7% (50.1, 57.4) of Hispanic/Latino, and 60.2% (58.3, 62.0) of other individuals. By clinical presentation, 44.1% (40.7, 47.6) of atypical clinical MCI, 52.6% (48.4, 56.7) of atypical dementia, 63.9% (61.8, 66.0) of typical MCI, and 59.9% (56.8, 62.8) of typical dementia participants had an overall change in management (Table 2). Logistic regression demonstrated significant interactions between Black/African American identity and positive amyloid PET scan (OR 1.64, 95% CI 1.14, 2.36; p 0.008) (Table 3).

New IDEAS demonstrated that amyloid PET use among ethnoracially diverse Medicare beneficiaries and those with atypical and typical clinical presentations of AD leads to changes in clinical management, highlighting the value of this biomarker in a real‐world clinical care setting.