Accuracy of patient recall of preoperative symptom severity (angina and breathlessness) at one year following aorta-coronary artery bypass grafting.

AIM AND
OBJECTIVE: The accuracy with which patients recall their cardiac symptoms prior to aorta-coronary artery bypass grafting is assessed approximately one year after surgery together with patient-related factors potentially influencing accuracy of recall.
BACKGROUND: This is a novel investigation of patient's rating of preoperative symptom severity before and approximately one year following aorta-coronary artery bypass grafting.
DESIGN: Patients undergoing aorta-coronary artery bypass grafting (n = 208) were recruited preoperatively and 177 of these were successfully followed up at 16.4 (SD 2.1) months after surgery and asked to describe current and recalled preoperative symptoms using a 15-point numerical scale.
METHOD: Accuracy of recall was measured and correlated (Pearson's correlation) with current and past symptoms, health-related quality of life and coronary artery disease risk factors. Hypothesis tests used Student's t-test and the chi-squared test.
RESULTS: Respective angina and breathlessness scores were recalled accurately by 16.9% and 14.1% while 59% and 58% were inaccurate by more than one point. Although the mean preoperative and recalled scores for severity of both angina and breathlessness and were not statistically different, patients who recalled most accurately their preoperative scores had, on average, significantly higher preoperative scores than those with less accurate recall. Patients whose angina and breathlessness symptoms were relieved by operation had significantly better accuracy of recall than patients with greater levels of symptoms postoperatively.
CONCLUSION: Patient's rating of preoperative symptom severity before and one year following aorta-coronary artery bypass grafting was completely accurate in approximately one sixth of patients with similar proportions of the remaining patients overestimating and underestimating symptoms. The extent to which angina and breathlessness was relieved by operation was a significant factor in improving accuracy of recall. RELEVANCE TO CLINICAL PRACTICE: Factors associated with accuracy of recall of symptoms provide useful insights for clinicians when interpreting patients' views of the effectiveness of aorta-coronary artery bypass grafting for the relief of symptoms associated with coronary heart disease.