Allostatic load and health: a crossed-lagged analysis of the English Longitudinal Study of Ageing (ELSA)

Allostatic load has been conceptualised as a biological burden induced by chronic stress which predicts health outcomes. Few studies have investigated whether this is the case. We investigate reciprocal associations between allostatic load, limiting long-term illness and self-rated health using cross-lagged longitudinal modelling. The sample included men and women aged 52+ who participated in Wave 2 (2004) and Wave 4 (2006) of English Longitudinal Study of Ageing (n = 4,688 in wave 4). Allostatic load was measured with nine biomarkers using a multisystem summary approach. Self-rated health was measured using a global 5-point indicator; the measure of limiting tong-term illness was dichotomous. Autoregressive cross-lagged models between allostatic load, limiting long-term illness and self-rated health in waves 2 and 4 were tested. Models were adjusted for age, gender and education in wave 2, and for time-varying variables of being married, wealth, physical activity, smoking, and social support. Allostatic load predicted limiting long-term illness. The association between allostatic load and self-rated health was reciprocal, and the strength of the estimates suggested that the path from poor self-rated health to low allostatic load score was stronger than the path from low allostatic load to poor self-rated health.