Health-related quality of life and functional performance predictors in secondary peritonitis patients

Introduction

Health-related quality of life (HR-QoL) is an important patient outcome, playing a complementary role to both mortality and long-term morbidity outcomes in the assessment and measurement of treatment effects and hospital process. Our aim is to determine predictive factors for the HR-QoL in patients with secondary peritonitis. We evaluated patient, surgery and postoperative characteristics to determine their roles in HR-QoL.

Methods

Patients participating in an ongoing trial evaluating surgical strategies for secondary peritonitis were consecutively surveyed by questionnaire 6 months after initial laparotomy. Eighty-three patients were asked to fill in the Euroqol-5 Dimensions (EQ-5D) and Euroqol Visual analogue scale (VAS) measuring HR-QoL, while their attending doctors assessed the Karnofsky performance scale, measuring functional impairment, at the outpatients clinic.

Statistical analysis

Univariate analysis was carried out using the Mann–Whitney U test, the Kruskal–Wallis analysis of ranks and the Wilcoxon rank test. Relationship significance was determined by the Spearman's rank correlation coefficient. Multivariate analyses were done by general linear model main effects model, using patient characteristics, disease characteristics and postoperative characteristics.

Results

The following factors were determined predictive in the univariate analysis and were therefore added to the multivariate analyses: age, gender, enterostomy, comorbidity (assessed by the Charlson index), type of contamination, and finally length of hospital stay (LOH) (LOH was used as a summary value to represent, length of ICU stay, ventilation duration, and the number of relaparotomies; as these were all highly correlated). Predictive factors for worse HR-QoL measured by the VAS, determining overall patient well-being, are: being female (β = -11.1, P = 0.009); having an enterostomy (β = -8.8 P = 0.049); purulent contamination (β = -11.0, P = 0.028); LOH stay (β = -14.5, P = 0.042); and severity of comorbidity (β = -3.6, P = 0.063). Predictive factors for poor mobility are: increasing age (P = 0.030); being female (P = 0.026); having an enterostomy (P = 0.014); and LOH stay (P = 0.019). Predictive factors for reduced ability to care for oneself are: having an enterostomy (P = 0.031); and LOH stay (P = 0.003). Predictive factors for limited ability to perform daily activities are: having an enterostomy (P = 0.011); LOH stay (P = 0.037); and severity of comorbidity (P = 0.018). Only being female (P = 0.060) was predictive for reporting more pain. Predictive factors for increased depression and anxiety are: being younger (P = 0.005); purulent contamination (P = 0.010); and faecal contamination (P = 0.003). LOH stay was the only predictive factor for the Karnofsky performance scale (β = -25.2, P < 0.001).

Conclusion

Six months following initial surgery, it appears that LOH stay and enterostomy are overall the most predictive factors for HR-Qol and functional impairment in patients with secondary peritonitis.