Longitudinal analysis of dementia diagnosis and specialty care among racially diverse Medicare beneficiaries.

Introduction: There is insufficient understanding of diagnosis of etiologic dementia subtypes and contact with specialized dementia care among older Americans.

Methods: We quantified dementia diagnoses and subsequent health care over five years by etiologic subtype and physician specialty among Medicare beneficiaries with incident dementia diagnosis in 2008/09 (226,604 persons/714,015 person-years).

Results: Eighty-five percent of people were diagnosed by a nondementia specialist physician. Use of dementia specialists within one year (22%) and five years (36%) of diagnosis was low. "Unspecified" dementia diagnosis was common, higher among those diagnosed by nondementia specialists (33.2%) than dementia specialists (21.6%). Half of diagnoses were Alzheimer's disease.

Discussion: Ascertainment of etiologic dementia subtype may inform hereditary risk and facilitate financial and care planning. Use of dementia specialty care was low, particularly for Hispanics and Asians, and associated with more detection of etiological subtype. Dementia-related professional development for nonspecialists is urgent given their central role in dementia diagnosis and care.