Health inequalities with the National Statistics-Socioeconomic classification: disease risk factors and health in the 1958 British birth cohort

Background: Health inequalities using the new National Statistics socioeconomic classification (NS-SEC) have so far been assessed using only general measures of health, with little known about inequality for specific health outcomes. Preliminary analyses show that self-employed workers, distinguished for the first time by NS-SEC, show increased mortality risk in the last 5 years of working life. We examined health inequalities for multiple disease risk factors and health outcomes, with particular reference to cardiorespiratory risk in the self-employed. Methods: 8952 participants in the 1958 British birth cohort with information on adult occupation and disease risk factors at 45 years. Systolic and diastolic blood pressure, body mass index, glycosylated haemoglobin, total and high density lipoprotein (HDL) cholesterol, triglycerides, fibrinogen, C-reactive protein, tissue plasminogen activator (t-PA), von Willebrand factor, total immunoglobulin E (IgE), one-second forced expiratory volume, 4kHz hearing threshold, visual impairment, depressive symptoms, anxiety, chronic widespread pain and self-rated health were measured. Results: Routine workers had poorer health than professional workers for most outcomes examined, except HDL cholesterol, triglycerides, t-PA and IgE in men; total cholesterol and IgE in women. Patterns of inequality varied depending on the outcome but rarely showed linear trend across the classes. Relative to professionals, own account workers (self-employed) did not show consistently increased levels of cardiorespiratory risk markers. Conclusions: Health inequalities are seen with NS-SEC across diverse outcomes for men and women. In mid-life, self-employed workers do not have an adverse cardiorespiratory risk profile.