Health-related quality of life 1-3 years post-myocardial infarction: its impact on prognosis

Abstract

Objective: To assess associations of health-related quality of life (HRQoL) with patient profile, resource use, cardiovascular (CV) events and mortality in stable patients post-myocardial infarction (MI).

Methods: The global, prospective, observational TIGRIS Study enrolled 9126 patients 1-3 years post-MI. HRQoL was assessed at enrolment and 6-month intervals using the patient-reported EuroQol-5 dimension (EQ-5D) questionnaire, with scores anchored at 0 (worst possible) and 1 (perfect health). Resource use, CV events and mortality were recorded during 2-years' follow-up. Regression models estimated the associations of index score at enrolment with patient characteristics, resource use, CV events and mortality over 2-years' follow-up.

Results: Among 8978 patients who completed the EQ-5D questionnaire, 52% reported 'some' or 'severe' problems on one or more health dimensions. Factors associated with a lower index score were: female sex, older age, obesity, smoking, higher heart rate, less formal education, presence of comorbidity (eg, angina, stroke), emergency room visit in the previous 6 months and non-ST-elevation MI as the index event. Compared with an index score of 1 at enrolment, a lower index score was associated with higher risk of all-cause death, with an adjusted rate ratio of 3.09 (95% CI 2.20 to 4.31), and of a CV event, with a rate ratio of 2.31 (95% CI 1.76 to 3.03). Patients with lower index score at enrolment had almost two times as many hospitalisations over 2-years' follow-up.

Conclusions: Clinicians managing patients post-acute coronary syndrome should recognise that a poorer HRQoL is clearly linked to risk of hospitalisations, major CV events and death.

Trial registration number: ClinicalTrials.gov Registry (NCT01866904) (https://clinicaltrials.gov).

Keywords: coronary artery disease; myocardial infarction; quality of healthcare.

Figure 1

(A) Distributions of the EQ-5D items and (B) the consequent EQ-5D index score and VAS score in 8978 patients at enrolment. EQ-5D, EuroQol-5 dimension; VAS, Visual Analogue Scale.

Figure 2

The associations of (A) baseline EQ-5D index score and (B) baseline VAS score with mortality and the composite outcome of CV death, MI, stroke and unstable angina requiring urgent revascularisation (using Poisson regression models with and without adjustment for other patient variables). Adjusted for variables in the TIGRIS index model: age ≥65 years; diabetes; second prior MI; chronic kidney disease; heart failure; peripheral artery disease; CV event in past 6 months; prior major bleed; medical management only of index MI; on diuretics at enrolment. CV, cardiovascular; EQ-5D, EuroQol-5 dimension; MI, myocardial infarction; VAS, Visual Analogue Scale.

Figure 3

Health resource use over 2-years’ follow-up by baseline self-rated health in 7846 patients with health resource data at every visit (using OLS regression models with and without adjustment for other patient variables). (A) EQ-5D index score and (B) EQ-5D VAS score adjusted for variables in the TIGRIS index model: age ≥65 years; diabetes; second prior MI; chronic kidney disease; heart failure; peripheral artery disease; CV event in past 6 months; prior major bleed; medical management only of index MI; on diuretics at enrolment. CV, cardiovascular; EQ-5D, EuroQol-5 dimension; ER, emergency room; GP, general practitioner; MI, myocardial infarction; OLS, Ordinary Least Squares; VAS, Visual Analogue Scale.