To investigate whether low self-rated health (SRH) is associated with increased mortality in individuals with diabetes.
Population-based prospective cohort study.
Enrolment took place between 1992 and 2000 in four centres (Bilthoven, Heidelberg, Potsdam, Umeå) in a subcohort nested in the European Prospective Investigation into Cancer and Nutrition.
3257 individuals (mean ± SD age was 55.8±7.6 years and 42% women) with confirmed diagnosis of diabetes mellitus.
Primary outcome measure
The authors used Cox proportional hazards modelling to estimate HRs for total mortality controlling for age, centre, sex, educational level, body mass index, physical inactivity, smoking, insulin treatment, hypertension, hyperlipidaemia and history of myocardial infarction, stroke or cancer.
During follow-up (mean follow-up ± SD was 8.6±2.3 years), 344 deaths (241 men/103 women) occurred. In a multivariate model, individuals with low SRH were at higher risk of mortality (HR 1.38, 95% CI 1.10 to 1.73) than those with high SRH. The association was mainly driven by increased 5-year mortality and was stronger among individuals with body mass index of <25 kg/m2 than among obese individuals. In sex-specific analyses, the association was statistically significant in men only. There was no indication of heterogeneity across centres.
Low SRH was associated with increased mortality in individuals with diabetes after controlling for established risk factors. In patients with diabetes with low SRH, the physician should consider a more detailed consultation and intensified support.
Is low self-rated health (SRH) associated with increased mortality in individuals with diabetes?
If so, is the association between SRH and mortality in individuals with diabetes moderated by socio-demographic and health-related variables?
Low SRH was associated with increased mortality in individuals with diabetes after controlling for established risk factors. The association was homogeneous across the four European Prospective Investigation into Cancer and Nutrition centres situated in three different European countries.
The association between low SRH and mortality was mainly driven by increased 5-year mortality in men and was stronger among individuals with body mass index <25 than among obese individuals.
Strengths and limitations of this study
To our knowledge, this is the first study that evaluates this research question in a population-based cohort of individuals with diabetes with long-term follow-up (up to a maximum of 14 years) in different European countries.
The association between SRH and mortality remained robust after controlling for potential confounders, including previous myocardial infarction, stroke or cancer, but we cannot rule out residual confounding from other comorbidity that was not assessed at baseline.