Abstract
Self-rated health (SRH) is one of the most frequently used indicators in health research. It is easy to use and considered as a valid measure of health because of its robust association with mortality. This association can largely be explained by the fact that in SRH summarized many health factors such as disease, functioning, and symptoms. Yet the biological basis of SRH is poorly understood. We investigated the association of SRH with several biomarkers measured from blood and urine in a large population sample where disease and functioning could be taken into account. Data were from MARK- AGE, a European-wide project on biomarkers of aging. The sample included 3252 individuals aged 18 to 92 years from eight European countries. SRH was categorized as poor&fair, good, very good and excellent. Multinomial logistic regression was used, contrasting “excellent” to “poor&fair”. Altogether 170 biomarkers were included in the preliminary analyses and, adjusted for age and gender, 42 of them showed a significant association with SRH. Adjusted for age, gender and cardiovascular diseases, arthritis, diabetes, elevated blood pressure, hypothyroidism/hyperthyroidism and respiratory diseases, still 33 biomarkers showed a significant association. Of these, the TOP5 strongest SRH-associations were with concentrations of beta-carotene (β=1.7), 25-hydroxyvitamin-D (β=0.03), lutein (β=3.7), beta-cryptoxanthine (β=2.3) and HDL-cholesterol (β=1.3) in plasma (all P<0.001). The findings suggest that SRH reflects the physiological state of the organism beyond the disease diagnoses, and better SRH is strongly associated with higher levels of plasma carotenoids that serve as biomarkers of fruit and vegetable intake.