%0 Journal Article
%T To what extent does IQ 'explain' socio-economic variations in function?
%A Hans Bosma
%A Martin PJ van Boxtel
%A Gertrudis IJM Kempen
%A Jacques van Eijk
%A Jelle Jolles
%J BMC Public Health
%D 2007
%I BioMed Central
%R 10.1186/1471-2458-7-179
%X The Maastricht Aging Study (MAAS) is a prospective cohort study based upon participants in a registration network of general practices in The Netherlands. Information was available on 1211 men and women, 24 ¨C 81 years old, who were without cognitive impairment at baseline (1993 ¨C 1995), who ever had a paid job, and who participated in the six-year follow-up. Main outcomes were longitudinal decline in important components of quality of life and successful aging, i.e., self-reported physical, affective, and cognitive functioning.Persons with a low occupational level at baseline showed more functional decline than persons with a high occupational level. Socio-economic and developmental factors from early life hardly contributed to the adult socio-economic differences in functional decline. Intellectual abilities, however, took into account more than one third of the association between adult socio-economic status and functional decline. The contribution of the intellectual abilities was independent of the early life factors.Rather than developmental and socio-economic characteristics of early life, the findings substantiate the importance of intellectual abilities for functional decline and their contribution ¨C as potential, but neglected confounders ¨C to socio-economic differences in functioning, successful aging, and quality of life. The higher intellectual abilities in the higher socio-economic status groups may also underlie the higher prevalences of mastery, self-efficacy and efficient coping styles in these groups.Lately there have been reports that lower intellectual abilities may result in poor physical functioning and even in heightened risks of mortality [1-9]. The mechanisms underlying the association, however, remain undetermined. In particular, the issue of whether lower intellectual abilities are related to poor health outcomes, independent of adverse socio-economic conditions in childhood and adulthood, remains unresolved [5,10]. A related unresolved iss
%U http://www.biomedcentral.com/1471-2458/7/179