Patients with greater levels of self-reported pain one year after a myocardial infarction (MI) have a significantly higher risk of subsequent mortality, according to a new study.
It is recognised that in patients with symptomatic chest pain, markers such as coronary artery calcium score and cystatin C levels are linked to a higher risk of all-cause mortality.
In addition, self-reported chronic pain is also linked to a higher risk of adverse cardiovascular outcomes including MI and stroke, independently of established cardiovascular risk factors. The extent to which any post-MI pain impacts on subsequent mortality is to be determined.
To this end, in the recent study, published in the Journal of the American Heart Association, Swedish researchers aimed to examine various levels of pain severity one year after an MI as a potential risk for all-cause mortality.
The team collated data from patients who had a registered MI event between 2004 and 2013 with measurements of potential cardiovascular risk indicators at hospital discharge from the Swedish quality register SWEDEHEART database.
Self-reported levels of experienced pain according to EuroQol-5 dimension instrument were recorded in secondary prevention clinics one year after their hospital discharge. The researchers set the primary outcome as all‐cause mortality.
Self-reported pain scores and mortality
A total of 18,376 patients with complete data were included in the analysis, and all-cause mortality data were collected up to 8.5 years (median 3.4 years) after the one-year visit. There were 1,067 recorded deaths.
Self-reported moderate pain and extreme pain were reported by 38.2% and 4.5% of included patients, respectively.
In fully adjusted models, the mortality risk among those with self-reported moderate severity pain was 35% higher than for those not reporting pain (hazard ratio, HR = 1.35, 95% CI 1.18 – 1.55, p < 0.0001).
But in those reporting severe pain, the risk was more than doubled (HR = 2.06, 95% CI 1.63 – 2.60, p < 0.0001). In fact, pain was a stronger mortality predictor than smoking.
The researchers suggested that clinicians managing post-MI patients should recognise the need to consider those with self-reported pain as a prognostic factor, which is comparable to persistent smoking, and to address this when tailoring secondary prevention treatments.