Objective:

To understand the path and barriers to Alzheimer’s disease diagnosis.

Background:

We analyzed the clinical care pathway of patients at varying AD stages.

Design/Methods:

Data were from the US Adelphi Real World Dementia Disease Specific Programme™ (December 2022‒September 2023). Physicians reported patient characteristics and disease severity, and patients reported their disease experience. Patients were aged ≥50 years with probable AD based on physician diagnosis and Mini-Mental State Examination (MMSE) scores: 26‒29, mild cognitive impairment (MCI) due to AD; 21‒25, mild AD dementia; 11‒20, moderate AD dementia; 0‒10, severe AD dementia.

Results:

Overall, 191 physicians (83 primary care physicians [PCPs], 108 specialists) reported data for 870 patients. Mean (SD) age was 74.7 (8.4) years and 48.3% were female. At initial diagnosis, 22% of patients had MMSE scores consistent with MCI due to AD; 49% mild, 26% moderate and 2% severe AD dementia.

Short-term memory loss prompted first physician evaluation for 83% of patients. Most patients (53.1%) delayed evaluation because they perceived memory issues as normal aging.

Median (IQR) time between symptom onset and first evaluation was 17.3 (4.4;43.4) weeks, and time from first evaluation to diagnosis was 3.0 (0.0;13.1) weeks. Before diagnosis, 47.0% of patients were referred to a secondary physician, with median time from first evaluation to referral of 8.7 (2.3;19.9) weeks. For referred patients, median time from first evaluation to diagnosis was 9.9 (3.1;26.2) weeks.

In 75.3% of cases, patients first visited a PCP (range: 71.4–76.8%, across severity subgroups). Specialists made 57.9% of initial diagnoses versus 41.8% by PCPs; 61.9% versus 38.1%, respectively, for MCI due to AD and 57.1% versus 42.9%, respectively, for severe AD dementia.

Conclusions:

Specialists were more likely to diagnose patients in the MCI stage. Delays in AD diagnosis are common, and new strategies to address these delays are warranted.