Socio-economic position at three points in life in association with type 2 diabetes and impaired glucose tolerance in middle-aged Swedish men and women.

BACKGROUND It has been suggested that low socio-economic position (SEP) during childhood and adolescence predicts risk of adult type 2 diabetes. We investigated the associations between type 2 diabetes and childhood SEP (fathers' occupational position), participants' education and adult SEP (participants' occupational position). To determine possible independent associations between early SEP (fathers' occupational position and participants' education) and disease, we adjusted for adult SEP and factors present in adult life associated with type 2 diabetes. METHODS This cross-sectional study comprised 3128 men and 4821 women aged 35-56 years. All subjects have gone through a health examination and answered a questionnaire on lifestyle factors. At the health centre, an oral glucose tolerance test was administered and identified 55 men and 52 women with previously undiagnosed type 2 diabetes. Relative risks (RRs) with 95% CIs were calculated in multiple logistic regression analyses. RESULTS The age-adjusted RRs of type 2 diabetes if having a father with middle occupational position were 2.3 [Confidence interval (CI:1.0-5.1) for women and, 2.0 (CI:0.7-5.6) for men]. Moreover, low education was associated with type 2 diabetes in women, RR = 2.5 (CI:1.2-4.9). Low occupational position in adulthood was associated with type 2 diabetes in women, RR = 2.7 (CI:1.3-5.9) and men, RR = 2.9 (CI:1.5-5.7). The associations between early SEP and type 2 diabetes disappeared after adjustment for adult SEP and factors associated with type 2 diabetes. CONCLUSION The association between type 2 diabetes and low SEP during childhood and adolescence in middle-aged Swedish subjects disappeared after adjustment for adult SEP and adult risk factors of diabetes.