Risk of cardiovascular mortality: The combined impact of impaired health related quality of life and diabetes mellitus

There is an established link There is an established link between Health Related Quality of Life (HRQL) and cardiovascular disease (CVD) mortality, however, few studies have determined the combined impact of diabetes mellitus (DM) and impaired HRQL on CVD mortality. We investigated if the combination of DM and impaired HRQL carry[apos]s a higher CVD risk than either component alone. The Australian Diabetes Obesity and Lifestyle study (AusDiab) included 11,247 adults aged [ge]25 years from 42 randomly selected areas of Australia. At baseline, in 1999-2000, diabetes status was defined using the World Health Organization criteria and HRQL was assessed using the SF-36 questionnaire. The SF-36 defined two summary scores: mental (MSC) and physical health component summary scores (PCS). Overall, after 7.4 years of follow-up, 57 of those with DM and 105 of those without DM had died from CVD. In individuals with and without DM, HRQL measures were significant predictors of increased CVD mortality. The hazard ratios (HRs) and 95% confidence intervals (CIs) for CVD mortality among those with DM or impaired PCS alone were similar, while those with both DM and impaired PCS had a much higher CVD mortality (DM only 1.4 (0.7-2.8), impaired PCS alone 1.7 (1.1-2.6), both DM and impaired PCS 3.3 (2.0-5.5), compared to those without DM and normal PCS (after adjustment for age, sex, smoking, history of CVD, systolic BP, lipid therapy, total cholesterol and triglycerides). For MCS the HRs for CVD mortality among those with DM only was 1.5 (95% CI 0.9-2.3) and impaired MCS alone was 0.8 (95% CI 0.5-1.4), while the HR for CVD mortality among those with both DM and impaired MCS was 2.5 (95% CI 1.4-4.5). This study has shown that the combination of DM and impaired HRQL is associated with substantially higher CVD mortality and it suggests that among those with DM, impaired HRQL is likely to be important in the identification of individuals at increased risk of CVD mortality.