Background: Changes in health-related quality of life (HRQoL) several days after surgery have rarely been investigated. We aimed to estimate the perioperative change of HRQoL, to identify patients with clinically relevant decrease in postoperative HRQoL and to establish factors associated with this decrease in HRQoL at day 30 after major surgery.

Methods: Patients scheduled for major surgery at a university hospital were enrolled. Based on the HRQoL SF-12 questionnaire, the preoperative physical component summary (PCS) score, preoperative mental component summary (MCS) score, and postoperative PCS and MCS scores at day 30 were recorded. Minimal clinically important difference (MCID) was defined as those with a decrease of at least one half of the standard deviation (SD) of preoperative PCS or MCS scores. Differences between the groups with or without decreased HRQoL were investigated using univariate comparisons. A multiple logistic regression model was performed to evaluate the predictive value of potential perioperative variables.

Results: The mean ± SD preoperative PCS score was 38.5 ± 10.6, postoperative score was 35.1 ± 7.8 (p = .004) in 85 patients. Thirty-five patients (41.2%) had a clinically relevant decrease of the postoperative PCS score. A normal to high preoperative exercise metabolic capacity measured with metabolic equivalent of task (MET) (p = .01) was a predictor of the decrease in postoperative PCS. The mean preoperative MCS scores (p = .395) were 42.2 (SD 12.8) preoperative, and 43.45 (SD 12.4) postoperative, respectively.

Conclusions: Major surgery decreases postoperative PCS scores of HRQoL at 30 days. A normal to high exercise capacity was a predictor of a clinically relevant decrease of postoperative PCS scores.

Trial registration: 07-107 (Ethical Committee NAC of Geneva University Hospitals).