Background and objectives: Self-rated health is a widely used measure of health status, but its biologic foundations are poorly understood. We investigated the association of frequently used biomarkers with self-rated health, and the role of these biomarkers in the association of self-rated health with mortality.
Methods: The relation of self-rated health to blood levels of albumin, white blood cell count, hemoglobin, HDL cholesterol, and creatinine was examined in a population-based sample of 4,065 men and women aged 71 years or older. A Cox proportional hazards model was used to determine the association of self-rated health with mortality during 4.9 years. Sociodemographic factors, diagnosed chronic conditions, and activities of daily living disability were controlled for in these analyses.
Results: All the biomarkers showed a graded relationship with self-rated health. After adjusting for other indicators, hemoglobin and white cell count were significantly associated with fair or poor self-rated health. When biomarkers and other indicators were adjusted for, self-rated health still was a significant predictor of mortality.
Conclusion: Self-rated health has a biologic basis, and it can be a sensitive barometer of physiologic states. Self-rated health is likely to predict mortality because it covers the spectrum of health conditions better than the variables measured in the study.