Allostatic load and stress biomarkers in a sample of community-dwelling older adults

Background: The idea that cumulative levels of stress can have deleterious effects on health and longevity has led investigators to discuss individual differences in the accumulation of Allostatic Load (AL) during life. Our aim was to evaluate the AL indices and stress biomarkers between genders and to determine which factors were more associated with AL indices. Methods: We evaluated 256 subjects, including 88 men and 168 women, aged 65 years or more. AL was measured by 10 biomarkers, including systolic and diastolic blood pressure, waist-hip ratio, glycosylated hemoglobin, salivary cortisol, salivary dehydroepiandrosterone sulphate, urinary epinephrine and norepinephrine, total cholesterol and total cholesterol/HDL. Sociodemographic and clinical characteristics, cognitive function and physical functional variables were additionally analyzed. Results: The mean age of the participants was 74.1 +/- 6.7 years. The AL index was 2.30 +/- 1.68, without a significant difference between gender. The final linear regression model controlling for gender, age, years of study and living arrangement showed that AL was associated to a number of chronic conditions (beta = 0.24; 95 % CI: 0.08-0.40), mobility disability (beta = 0.58; 95 % CI: 0.06-1.14), and handgrip strength (beta = 0.06; 95 % CI: 0.06-1.14). Conclusion: As a result of this investigation, Allostatic load was shown to be associated with poor health or physical function for community-dwelling older adults.