Heterogeneity in risk factors for cognitive impairment, no dementia: population-based longitudinal study from the Kungsholmen Project.
OBJECTIVE
The objectives of this study were to investigate the relation of vascular, neuropsychiatric, social, and frailty-related factors with "Cognitive impairment, no dementia" (CIND) and to verify their effect independently of future progression to Alzheimer disease (AD).


METHODS
Seven hundred eighteen subjects aged 75+ years who attended baseline, 3- and 6-year follow-up examinations of the Kungsholmen Project, a Swedish prospective cohort study, were studied. CIND was defined according to the performance on the Mini-Mental State Examination. Potential risk factors were collected at baseline and clustered according to four research hypotheses (frailty, vascular, neuropsychiatric, and social hypothesis), each representing a possible pathophysiological mechanism of CIND independently of subsequent development of AD.


RESULTS
Over a mean 3.4 years of follow up, 82 participants (11.4%) developed CIND. When the population was subsequently followed for a mean of 2.7 years, subjects with CIND had a threefold increased risk to progress to AD. After multiple adjustments, including adjustment for the development of AD at the 6-year follow up, risk factors for CIND were hip fracture, polypharmacy, and psychoses.


CONCLUSIONS
The results suggest that not only the AD-type neurodegenerative process, but also neuropsychiatric- and frailty-related factors may induce cognitive impairment in nondemented elderly. These findings may have relevant preventive and therapeutic implications.
Monastero
Roberto
R
Aging Research Center, Division of Geriatric Epidemiology, Department for Neurobiology, Health Care Sciences, and Society, Karolinska Institutet, Stockholm Gerontology Research Center, Stockholm, Sweden. roberto.monastero@ki.se
Palmer
Katie
K
Qiu
Chengxuan
C
Winblad
Bengt
B
Fratiglioni
Laura
L
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000523:psychology; D003072:Cognition Disorders / Q000453:epidemiology* / Q000209:etiology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006620:Hip Fractures / Q000523:psychology; D006801:Humans; D008297:Male; D019338:Polypharmacy; D016016:Proportional Hazards Models; D011618:Psychotic Disorders / Q000523:psychology; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology