INTRODUCTION

If mild cognitive impairment (MCI) is diagnosed after dementia, it suggests either the dementia diagnosis was premature, or the MCI diagnosis is incorrect. We investigated the prevalence and predictors of such "diagnostic reversion"-MCI diagnosis following dementia diagnosis-in a large academic health system.

METHODS

Among 5,965 patients aged 50+ with incident dementia in UCSF Health electronic health records, we identified "reverters" with a subsequent MCI diagnosis. We used Group LASSO-regularized logistic regression and random forest models to identify predictors.

RESULTS

Reversion occurred in 13.7% of patients. Lower odds were observed among older adults (OR=0.95/year; 95% CI: 0.92-0.98), while higher odds were found among Spanish speakers (OR=2.26; 95% CI: 1.28-4.00), those with greater cardiovascular risk (OR=1.16; 95% CI: 1.01-1.33), and higher Charlson comorbidity burden (OR=1.09; 95% CI: 1.05-1.14).

DISCUSSION

Diagnostic reversion is common and socially patterned, suggesting contributions from misdiagnosis, clinical uncertainty, or variability in clinical presentation and care setting.