The effect of direct cognitive assessment in the Medicare annual wellness visit on dementia diagnosis rates

Objective: To evaluate the relationship between direct cognitive assessment introduced with the Medicare Annual Wellness Visit (AWV) and new diagnoses of dementia, and to determine if effects vary by race. Data Sources: Medicare Limited Data Set 5% sample claims 2003-2014 and the HRSA Area Health Resources Files. Study Design: Instrumental Variable approach estimating the relationship between AWV utilization and new diagnoses of dementia using county-level Welcome to Medicare Visit rates as an instrument. Data Collection/Extraction Methods: Three hundred twenty-four thousand three hundred and eighty-five fee-for-service Medicare beneficiaries without dementia when the AWV was introduced in 2011. Principal Findings: Annual Wellness Visit utilization was associated with an increased probability of new dementia diagnosis with effects varying by racial group (categorized as white, black, Hispanic/Latino, or Asian based on Social Security Administration data). Hazard ratios (95% confidence intervals) for new dementia diagnosis within 6 months of AWV utilization were as follows: 2.34 (2.13, 2.58) white, 2.22 (1.71, 2.89) black, 4.82 (2.94, 7.89) Asian, and 6.14 (3.70, 10.19) Hispanic (P <.001 for each). Our findings show that estimates that do not control for selection underestimate the effect of AWV on new diagnoses. Conclusions: Dementia diagnosis rates increased with AWV implementation with heterogenous effects by race and ethnicity. Current recommendations by the United States Preventive Services Task Force state that the evidence is insufficient to recommend for or against screening for cognitive impairment in older adults.