Association Between a Self-Rated Health Question and Mortality in Young and Old Dialysis Patients: A Cohort Study Melissa S.Y. Thong, MSc, 1 Adrian A. Kaptein, PhD, 2 Yael Benyamini, PhD, 3 Raymond T. Krediet, MD, PhD, 4 Elisabeth W. Boeschoten, MD, PhD, 5 and Friedo W. Dekker, PhD, 1 on behalf of the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD) Study Group Background: Self-rated health (SRH) has been shown to predict mortality in large community-based studies; however, large clinical-based studies of this topic are rare. We assessed whether an SRH item predicts mortality in a large sample of incident dialysis patients beyond sociodemographic, disease, and clinical measures and possible age interaction. Study Design: Prospective cohort study. Setting & Participants: 1,443 predominantly white patients from 38 dialysis centers in The Nether- lands participating in the Netherlands Cooperative Study on the Adequacy of Dialysis-2 between 1997 and 2004. Predictor: SRH score completed at 3 months after the start of dialysis therapy (baseline). Outcomes & Measurements: Cox proportional hazards model estimated the association between SRH and all-cause mortality. Interaction of SRH with age (65 and 65 years) was examined in an additive model. Results: Mean age of patients was 59.6  14.8 years, with 61% men and 69% married/living together. Mean follow-up was 2.7  1.8 years. Deaths per SRH group in the multivariate analyses sample: excellent/very good (9 of 63 patients; 14.3%), good (148 of 473 patients; 31.3%), fair (194 of 508 patients; 38.2%), and poor (45 of 71 patients; 63.4%). Patients with poor, fair, or good health ratings had a greater mortality risk than those with excellent/very good health ratings (adjusted hazard ratio [HR adj ], 3.56; 95% confidence interval [CI], 1.71 to 7.42; HR adj , 2.09; 95% CI, 1.06 to 4.12; HR adj , 1.87; 95% CI, 0.95 to 3.70, respectively) independent of a range of risk factors. No age interaction with SRH was found. Limitations: Although the SRH-mortality association remained strong despite extensive adjust- ments, unknown residual confounding could still exist. Conclusion: SRH is an independent predictor of mortality in incident dialysis patients. Patients with poor SRH in both age strata had a significantly increased risk of mortality even after controlling for demographic and clinical confounders. Patient self-assessment of health can be an invaluable and economical complement to clinical measures in risk assessment. Am J Kidney Dis 52:111-117. © 2008 by the National Kidney Foundation, Inc. INDEX WORDS: Self-rated health; mortality; dialysis; age interaction. H ow are you feeling today? So simple a ques- tion, and so often asked as a polite opener during consultation, can provide a wealth of infor- mation about patients’ health perceptions and out- comes. Irrespective of its phrasing, this seemingly simple global self-rated health (SRH) item has been shown to be as powerful in predicting mortal- ity as more detailed health assessments or objec- tive clinical measures. In both community- 1-3 and clinical-based studies, 4,5 a strong association between SRH and mortality persisted even after controlling for demographic, clinical, and health factors. A study of 2,885 catheterized patients with coronary heart disease reported that patients with poor self-health ratings had a significantly increased risk of both all-cause and coronary heart disease–related mortality, even after exten- sive adjustment for mortality risk factors. 6 From the Departments of 1 Clinical Epidemiology and 2 Medical Psychology, Leiden University Medical Center, Leiden, The Netherlands; 3 Bob Shapell School of Social Work, Tel Aviv University, Tel Aviv, Israel; 4 Department of Nephrology, Academic Medical Center, University of Amster- dam, Amsterdam; and 5 Hans Mak Institute, Naarden, The Netherlands. Received July 31, 2007. Accepted in revised form April 2, 2008. Originally published online as doi: 10.1053/j.ajkd.2008.04.001 on May 22, 2008. A list of the members of the NECOSAD Study Group appears at the end of this article. Address correspondence to Melissa S.Y. Thong, MSc, Department of Clinical Epidemiology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Nether- lands. E-mail: m.thong@lumc.nl © 2008 by the National Kidney Foundation, Inc. 0272-6386/08/5201-0015$34.00/0 doi:10.1053/j.ajkd.2008.04.001 American Journal of Kidney Diseases, Vol 52, No 1 (July), 2008: pp 111-117 111