Recent research sheds light on link between mortality outcomes and psychosocial variables for cardiac bypass patients



Research by Dr. Wolfgang Linden, professor emeritus in UBC’s department of psychology, is the first to measure the relationship between long-term morbidity and mortality outcomes and psychosocial variables for cardiac bypass recipients.

Dr. Linden and his research collaborators used psychosocial assessments conducted shortly after cardiac bypass surgery, as well as medical charts and provincial death records 14 years later, to study what psychosocial variables are associated with life expectancy following surgery. They found that depression, household responsibility and functional impairment at 1 year after surgery were associated with long-term mortality. Additionally, depression was found to be related to increased likelihood of another cardiac event.

This research shows how vital it is to include psychological and psychosocial variables in long-term follow-ups—and how psychological variables can become a determinant of life expectancy over time.

“Longitudinal studies are critical if we want to understand what causes what. The key finding in this study is that short-term health benefit is likely driven by the quality of medical care but when it comes to understanding long-term prediction of survival and well-being psychological factors become more and more important over time.”
Professor Emeritus

Dr. Wolfgang Linden, lead author of the study Psychosocial and medical predictors of 14-year mortality and morbidity in male and female coronary artery bypass graft recipients: a prospective observational study, joins us for a Q&A, where he discusses how this research can shape future cardiac care.

What is this study about?

This study tracked adjustment of cardiac bypass recipients over a mean follow-up of 14 years. The average patient has a mean lifespan of around fifteen years following this surgery but this is highly variable and we need to know what determines life expectancy. The same psychosocial variables were assessed twice, namely within 3-5 days of the surgery and one year later. Medical charts and provincial death records provided objective long-term outcome data 14 years later. Importantly, sampling had continued until an adequate balance of male and female participants was obtained. Overall, depression, household responsibility and functional impairment were prospectively associated with long-term mortality and also to urgent recurrence of another cardiac procedure over and above traditional medical risk factors. Social support was not differentially associated with a main effect for outcomes. Year one functional and emotional adjustment status was a better predictor of long-term cardiac outcome than was the corresponding status immediately following CABG. These results were equally relevant for men and women.

What do your research findings show?

Long-term follow-ups with medical and psychological measures including mortality are rare because they are expensive and logistically challenging. However, such longitudinal studies are critical if we want to understand what causes what. Bypass surgery is given to men about 3x as often as to women and it was hard to get a large sample of female research participants for our study (but we did succeed, with much effort!). The key finding is that short-term health benefit is likely driven by the quality of medical care but when it comes to understanding long-term prediction of survival and well-being psychological factors become more and more important over time.

How is this study relevant for society?

I will argue that the most important take-home message is that cardiac care needs to be undertaken with a long-term perspective and psychological needs of bypass patients need to be reassessed and monitored repeatedly once the medical crisis and initial adjustment are over. There needs to be an integrated system of medical and psychological care that hold hands with each other. COVID-19 for example forced the cardiac rehabilitation program to shut down and this puts many patients at risk for renewed cardiac problems. Our study results certainly justify a re-establishment of in-person cardiac rehabilitation as soon as possible.