Background: Self-rated health is frequently used as a health outcome variable in population studies. The aim of this study was to investigate the association between self-rated health and mortality in a Norwegian population.
Material and methods: We used data from the first "Nord-Trøndelag Health Study" in 1984-1986 (HUNT 1), where 76,793 persons aged 20 years and older participated (90.7 % of the total adult county population). Average follow-up time was 16.4 years (median 18.9 years). Mortality risks in different groups were estimated using Cox' regression analyses, adjusted for age, education and chronic disease.
Results: Compared to participants with very good self-rated health, men with poor self-rated health had a relative increased mortality risk (hazard ratio) of 2.37 (95 % CI 2,09-2,70) and women of 2.37 (95 % CI 2.05-2.76), when adjusted for age, education and chronic disease. Poor self-rated health gave a mortality risk of 2.99 (95 % CI 2.76-3.23), compared to self-reported myocardial infarction 2.02 (95 % CI 1.92-2.12) and diabetes 1.99 (95 % CI 1.90-2.09), adjusted for age and gender.
Interpretation: Adults who participate in health surveys and rate their health to be poor have a higher mortality as a group than those with a good self-rated health, even higher than those with self-reported cardiac infarction or diabetes. Our findings strengthen the impression that self-rated health is a very important health indicator in population studies.