Williams JW (Durham COE), Holsinger TC
(Durham COE), Stechuchek KM
(Durham COE), Coffman C
(Durham COE)
Objectives:
To estimate an overall prevalence of dementia in primary care (PC) patients using administrative and prospectively collected data at Durham VAMC.
Methods:
Prospective study (GEMS):
Subjects were identified from upcoming PC appointments based on eligibility criteria of age > = 65, at least 2 visits to primary care within the past 18 months, living within 90 miles of the Durham VAMC in a non-institutional setting with no ICD-9 diagnoses of dementia or psychosis and an AUDIT C < 7. Consenting subjects were evaluated by a research nurse using the CERAD neuropsychological battery, a semi-structured questionnaire and medical history review. Informants completed an interview about the subject’s cognitive and functional ability. An experienced panel of clinicians applied DSM-IV criteria to achieve a consensus diagnosis of normal, cognitive impairment no dementia, or dementia. We estimated unrecognized dementia using the percentage diagnosed with dementia.
Administrative pull:
Subjects were identified based on having a PC visit between May 2006-May 2008, age > = 65, at least 2 visits to PC within the past 18 months, living within 90 miles of the Durham VAMC, with no ICD-9 codes for psychosis. Excluded were veterans enrolled in the GEMS study. We estimated recognized dementia using the percentage having a dementia ICD-9 code.
Overall dementia prevalence:
We applied the unrecognized dementia rate to those who did not have an ICD-9 dementia code and combined them with those with recognized dementia to get the overall dementia prevalence rate.
Results:
Demographic characteristics for the 6,663 identified in the administrative data pull were: mean age 76.1 ± 6.7 years; 99% male; 62.5% white, 21.5% black, 14.8% unknown, and 1.2% other. GEMS study subjects were similar demographically.
In the GEMS study, 21 of 478 (4.4%) were given a consensus diagnosis of dementia. In administrative data, 463 veterans had a dementia ICD-9 code (6.9%). We estimate that 272 veterans have unrecognized dementia. The combined estimate of recognized and unrecognized dementia is 735/6,663 (11.0%).
Implications:
Administrative data may significantly underestimate the prevalence of dementia in veterans.
Impacts:
As the U.S. population ages, accurate estimates of dementia prevalence are needed to inform planning for expenditures in all healthcare settings. Current VA projections for dementia range 3.6-5.1% and may significantly underestimate coming needs.
If these data are confirmed in other VA outpatient settings, policy planners should be better prepared for increased related expenditures as the Vietnam-era cohort ages.