Abstract:
A documented diagnosis only benefits patients who know about it. Using nationally representative Health and Retirement Study data linked to Medicare claims (1998-2020), we quantify the gap between clinically documented dementia diagnoses and patients' own reports. Among self-respondents with probable dementia and a claims-based diagnosis, 67 percent do not report having been diagnosed-more than double the average underreporting rate for arthritis, hypertension, diabetes, and depression among the same population-and underreporting is highest in the early disease stage, precisely when decision-making capacity is greatest. Underreporting is more prevalent among individuals who live alone, are dually eligible, have less education, and are non-Hispanic Black, and less prevalent among Medicare Advantage enrollees and patients seen by dementia specialists, consistent with roles for stigma, social vulnerability, and provider disclosure incentives. Underreporting predicts lower post-diagnosis care engagement and a lower likelihood of establishing a will or trust, suggesting information frictions undermine the returns to early detection.
