Mild cognitive impairment and dementia in primary care: the value of medical history.

BACKGROUND: Primary care should be the place for the early detection of mild cognitive impairment (MCI) and dementia; however, a considerable proportion of these processes remain undetected at this setting. Family doctors may not have enough time or expertise for cognitive testing. The utility of clinical variables, other than cognitive tests, has hardly been investigated.

OBJECTIVES: To explore the diagnostic and prognostic value of the variables that are usually collected in the medical history of patients with suspected cognitive impairment.

METHODS: In this cohort study, people aged ≥ 50 years were prospectively searched for cognitive decline of unknown aetiology by seven primary care physicians (PCP) during their practice. The baseline assessment included demographic variables, symptom-related variables, medical and psychiatric co-morbidity, family history of dementia and neurological exam. The diagnosis was made by a neurologist at baseline and after 1 year.

RESULTS: One hundred and seventy-six patients were analysed of whom 81 (46.0%) had MCI and 18 (10.2%) had dementia at baseline. After 1 year, 8 (9.9%) MCI patients had progressed to dementia, but 48 (59.3%) had reverted to normal cognition. Old age, source of symptoms (informant or PCP), short duration and low education were associated with MCI or dementia at baseline; low education predicted progression to dementia in MCI patients and less chronic medical conditions and younger age predicted reversion from MCI to normal cognition (P < 0.05, adjusted regression models).

CONCLUSION: Clinical data usually collected on medical history by PCP are useful to detect patients with MCI and dementia and also to predict MCI outcome.