Objective: To explore whether determinants of global quality of life (QOL) change before and after major cancer surgery.
Methods: Consecutive patients (n = 145) undergoing surgery for upper gastrointestinal cancer were prospectively studied and asked to complete the EORTC QLQ-C30 before and after 6 months. Excluded were patients found to be inoperable (n = 12) and those with missing second questionnaires (because of death n = 20, poor health (n = 10), administrative failure (n = 7) or patient refusal (n = 4)). Multivariable linear regression models investigated associations between global QOL and other scales and items of QOL adjusting for clinical variables.
Results: Some 87 patients completed both questionnaires. Before surgery the main predictors of global QOL were physical and emotional function, with adjusted increases in global QOL of 0.55 (95% CI 0.26-0.84; P < 0.001) and 0.30 (95% CI 0.14-0.45; P < 0.001) per unit increase of physical and emotional function, respectively. Six months after surgery, however, fatigue and dyspnea most strongly predicted global QOL, with adjusted differences in global QOL of -0.24 (95% CI -0.44 to -0.04; P = 0.02) per unit increase of fatigue and -6.28 (95% CI -12.64 to 0.07; P = 0.05) for those experiencing any symptoms of dyspnea.
Conclusion: Further work is needed to test these findings, but the results suggest that the global QOL scale in the QLQ-C30 is difficult to interpret and it should be considered within the context of other clinical and patient reported outcomes.