Associations of very high C-reactive protein concentration with psychosocial and cardiovascular risk factors in an ageing population

Abstract

Background: Raised levels of C-reactive protein (CRP), a marker of low grade systemic inflammation, is common in ageing populations although the relevance of very highly elevated CRP (>10mg/L) remains unclear. We examined cross-sectional associations of very high CRP with psychosocial, behavioural, and cardiovascular risk factors.

Methods: Participants were 5307 men and women from the English Longitudinal Study of Ageing, a study of community dwelling older adults (46.0% men, aged 66.5+/-10.1 years). Psychosocial (social status, marital status, depressive symptoms), behavioural (smoking, physical activity, alcohol), and cardiovascular risk factors (blood pressure, cholesterol, glycated haemoglobin, body mass index, waist) were assessed in relation to CRP.

Results: A very high CRP concentration was recorded in 7.5% of the sample. After adjustments for age, sex, acute infection and chronic inflammatory conditions, very high CRP was associated with lower social position, depressive symptoms, physical inactivity, smoking, and alcohol abstinence. There was a linear trend for increased prevalence of cardiovascular risk factors across CRP categories representing low (<1mg/L), medium (1 to <3mg/L), high (3-10mg/L), and very high (>10mg/L), although little differences in risk between high and very high groups were observed.

Conclusions: Very high levels of CRP in elderly participants might reflect chronic health and psychosocial adversity, independently of acute infection.