Statsols Blog

STUDY: Pre-surgical depression and anxiety and recovery following coronary artery bypass graft surgery

nQuery Sample Size Calculator has been featured in another interesting study, this time published in the Journal of Behavioral Medicine.

The study states that "co-morbid depression is commonly observed in patients suffering from coronary heart disease (Dickens 2015). Two landmark studies documented the impact of depression on survival following coronary artery bypass graft (CABG) surgery".

The study "aimed to explore the combined contribution of pre-surgical depression and anxiety symptoms for recovery following coronary artery bypass graft (CABG) using data from 251 participants. Participants were assessed prior to surgery for depression and anxiety symptoms and followed up at 12 months to assess pain and physical symptoms, while hospital emergency admissions and death/major adverse cardiac events (MACE) were monitored on average 2.68 years after CABG." 

"After controlling for covariates, baseline anxiety symptoms, but not depression, were associated with greater pain (β = 0.231, p = 0.014) and greater physical symptoms (β = 0.194, p = 0.034) 12 months after surgery.

On the other hand, after controlling for covariates, baseline depression symptoms, but not anxiety, were associated with greater odds of having an emergency admission (OR 1.088, CI 1.010–1.171, p = 0.027) and greater hazard of death/MACE (HR 1.137, CI 1.042–1.240, p = 0.004). These findings point to different pathways linking mood symptoms with recovery after CABG surgery."

Study Results featuring nQuery Sample Size Calculator

(Below is an extract from the results of the study. For full details of how nQuery Sample Size Calculator was used including details regards power analysis, outcome variables, covariates and statistical methods, please read the Full Study here.)

"Descriptive characteristics of the sample are displayed in Table 1. The majority of participants were male (87.0 %), overweight (BMI >25 = 82.5 %) and of White ethnic origin (88.0 %). Predicted mortality risk according to EuroSCORE ranged from 1.5 % to 22.0 %. Comorbidities were common, particularly diabetes which was present in a quarter of participants and hypertension (79.3 %).
The majority of participants underwent on-pump surgery in isolation. Depression and anxiety symptoms were prevalent at baseline. Over a third (35.9 %) of participants reported moderate to severe depression symptoms (BDI scores ≥10) and just under a third of participants (31.9 %) reported anxiety symptoms within the mild to severe range (HADS score ≥8). Depression and anxiety symptoms were significantly correlated (r = 0.641,p < 0.001).
Twelve-months following CABG surgery approximately half (48.9 %) of participants were still experiencing some pain, and 90.3 % had physical symptoms relating to their surgery. Sensory pain and physical symptom reporting were positively correlated (r = 0.690, p < 0.001). With regards to the clinical outcomes there were 19 death/MACE events of which 9 participants died, 8 participants experienced a MACE, and a further 2 participants experienced both MACE and death."

Cite: Poole, L., Ronaldson, A., Kidd, T. et al. J Behav Med (2016). doi:10.1007/s10865-016-9775-1

Topics: nQuery Publications Citing nQuery Sample Size Calculator