The impact of cancer type, treatment, and distress on health-related quality of life: cross-sectional findings from a study of Australian cancer patients.

PURPOSE: This study examined the mediating effects of cancer type, treatment, and distress on health-related quality of life (HRQoL) for early diagnosis cancer patients. Results were interpreted with respect to established thresholds for clinical meaningfulness. METHODS: A cross-sectional design was used. Patients completed surveys collecting demographics, cancer type, treatment, comorbid conditions, distress (HADS), and HRQoL (FACT-G). Hierarchical multivariate regressions examined associations between cancer type, treatment, and distress on HRQoL. Established minimum differences were used to identify clinically meaningful changes in HRQoL. RESULTS: Of the 1183 patients surveyed, 21% were classified as having elevated anxiety and 13% had elevated depression. Our sample reported significantly lower physical and emotional well-being compared to population norms. Patients with prostate, melanoma, gynaecological, and urological cancers had higher HRQoL scores than those with colorectal cancer. However, when effects for treatment type and distress were considered, differences between cancer types became non-significant. Anxiety and depression were associated with lower HRQoL scores as was chemotherapy. Only depression, anxiety, and chemotherapy were associated with clinically meaningful decreases in HRQoL scores. CONCLUSIONS: While statistically significant differences in HRQoL were found between different cancer types, only chemotherapy, anxiety, and depression produced clinically meaningful poorer HRQoL scores. In practice, clinically meaningful differences could promote a shift in resources toward interventions where a positive effect on patient well-being is appreciated by both the patient and health professional.