Patient-reported health and 1-year mortality in patients with ischemic heart disease – findings from the Denheart study

Background

Though survival has improved markedly in ischemic heart disease (IHD), it remains a leading cause of death worldwide. Screening tools to identify patients at risk are ever in demand. Large-scale studies exploring the association between patients' self-reported mental and physical health and mortality are lacking.

Purpose

(i) to describe patient-reported outcomes (PROs) at discharge in IHD patients deceased and alive at one year, (ii) to investigate the discriminant predictive performance of PRO instruments on mortality, (iii) to investigate differences in time to death among survey responders/non-responders and among three diagnostic sub-groups (chronic ischemic heart disease/stable angina, non-STEMI/unstable angina and STEMI), and (iv) to investigate predictors of one-year mortality among sociodemographic, clinical and self-reported factors.

Methods

Data from the national DenHeart survey with register-data linkage was used. A total of 14,115 adults with IHD were discharged during one year. Eligible (n=13,476) were invited to complete a questionnaire and 7,167 (53%) responded. Questionnaires included the Health survey short form 12-items (SF-12), Hospital Anxiety and Depression Scale (HADS), EuroQoL-5-dimensions (EQ-5D), HeartQoL, Edmonton Symptom Assessment Scale (ESAS) and ancillary questions. Clinical and demographic characteristics were obtained from registries as were data on one-year mortality. Comparative analyses investigated differences in PROs, and discriminant PRO-performance was explored by Receiver Operating Characteristics (ROC) curves. Kaplan-Meier survival analysis explored differences in time to death across sub-groups. Predictors of mortality were explored using multifactorially adjusted cox regression analyses with time to death as underlying timescale.

Results

Highly significant and clinically important differences in PROs were found between those alive and those deceased at one year. The best discriminant performance was observed for the physical component scale of the SF-12 (Area Under the Curve (AUC) 0.706) (Figure 1). One-year mortality among responders and non-responders was 2% and 7%, respectively. Significant differences in time to death was observed between responders and non-responders (p<0.001) and among diagnostic subgroups (p<0.001). Strongest predictors of one-year mortality included STEMI (hazard ratio (HR) 2.9 95% confidence interval (CI) 2.3–3.7), Tu comorbidity index score 3+ (HR 3.6, 95% CI 2.7–4.8) and patient-reported feeling unsafe about returning home from hospital (HR 2.07, 95% CI 1.2–3.61).

Conclusions

One-year post-discharge mortality was expectedly low, however notably higher in certain subgroups. Though clinical predictors may be difficult to modify, factors such as feeling unsafe about returning home should be addressed at discharge. PRO-performance estimates may guide clinicians and researchers in choosing appropriate predictive patient-reported outcome tools.

Figure 1. PRO instruments ROC curves

Funding Acknowledgement

Type of funding source: None