Socioeconomic differences in cognitive decline and the role of biomedical factors.
OBJECTIVE
This study examines the association between socioeconomic status and cognitive decline in a community-based cohort of well-functioning older adults and seeks to determine whether this link could be explained by biomedical factors.


METHODS
Data are from 2574 men and women aged 70 to 79 years from Pittsburgh, PA, and Memphis, TN, participating in the Health, Aging and Body Composition study (Health ABC). Three indicators of socioeconomic status were used: education, income, and ownership of financial assets. Cognitive decline over 4 years was defined as a decrease of five points or more in the Modified Mini-Mental State Examination (3MS) score. Biomedical factors measured at baseline, included heart disease, cerebrovascular disease, diabetes, hypertension, poor pulmonary function, and high serum levels of inflammatory markers.


RESULTS
Adjusted odds ratios were significantly higher in those with low education, low income, and few assets. Odds ratios ranged from 1.51 to 2.16 in the lowest socioeconomic groups. Additional adjustment for biomedical factors reduced the odds ratios of cognitive decline by an average of 2% for education, 5% for income, and 8% for the number of assets.


CONCLUSIONS
Low socioeconomic status predicts a decline in cognitive function in older adults and this relationship is not mediated by biomedical factors.
Koster
Annemarie
A
Department of Health Care Studies, Section Medical Sociology, Universiteit Maastricht, Maastricht, The Netherlands. a.koster@zw.unimaas.nl
Penninx
Brenda W J H
BW
Bosma
Hans
H
Kempen
Gertrudis I J M
GI
Newman
Anne B
AB
Rubin
Susan M
SM
Satterfield
Suzanne
S
Atkinson
Hal H
HH
Ayonayon
Hilsa N
HN
Rosano
Caterina
C
Yaffe
Kristine
K
Harris
Tamara B
TB
Rooks
Ronica N
RN
Van Eijk
Jacques Thm
JT
Kritchevsky
Stephen B
SB
D000368:Aged; D003072:Cognition Disorders / Q000209:etiology*; D005260:Female; D015577:Geriatric Assessment; D006304:Health Status; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012923:Social Class