Health-related quality of life of Chinese patients with colorectal neoplasms

Abstract

Increasing number of people is diagnosed with colorectal neoplasms (CRN) in the form of polyps or cancers. Colorectal cancer (CRC) is one of the most common causes of cancer deaths among Chinese in Hong Kong. Advances in diagnosis and treatments have increased the survival rate of CRN patients, resulting in a large group of cancer survivors. Preserving and maintaining health-related quality of life (HRQOL) has become an important direction in research and clinical care of patients with CRN. This research aimed to evaluate the HRQOL and its association with socio-demographics and disease-related characteristics among patients with CRN, and illustrate how HRQOL data could be converted to preference for the estimation of quality adjustment of life years in health economic evaluations.

This research comprised of three parts. First was the establishment of the validity and reliability of the traditional Chinese version of Functional Assessment of Cancer Therapy-Colorectal (FACT-C) as a HRQOL measure for Chinese patients by a cross-sectional sample of 536 adult patients with CRN. Psychometric testing and concurrent validation of the FACT-C with European Organization for Research and Treatment of Cancer Core Questionnaire plus Colorectal-specific Module Questionnaire and the Short-Form 12-item Health Survey_Version2 (SF-12V2) were carried out. Second was a longitudinal study on the HRQOL of 554 CRN patients at baseline, six (n=479) and twelve (n=414) months of recruitment. The associations of HRQOL with socio-demographics and disease-related factors, and change of HRQOL over time were explored. Comparisons of HRQOL between CRN patients and the general population and among different CRN groups were made. Cross-sectional data were used to develop mapping functions to estimate SF-6D preference scores from FACT-C subscale scores. Third was the application of the health preference scores by CRN stages collected at baseline of the longitudinal study, in combination with survival data extracted from the literature in a Markov model on the cost-effectiveness of different CRC screening strategies (colonoscopy, guaiac and immunochemical fecal occult blood tests) in comparison to no screening in terms of quality-adjusted life-years gained.

This research comprised of three parts. First was the establishment of the validity and reliability of the traditional Chinese version of Functional Assessment of Cancer Therapy-Colorectal (FACT-C) as a HRQOL measure for Chinese patients by a cross-sectional sample of 536 adult patients with CRN. Psychometric testing and concurrent validation of the FACT-C with European Organization for Research and Treatment of Cancer Core Questionnaire plus Colorectal-specific Module Questionnaire and the Short-Form 12-item Health Survey_Version2 (SF-12V2) were carried out. Second was a longitudinal study on the HRQOL of 554 CRN patients at baseline, six (n=479) and twelve (n=414) months of recruitment. The associations of HRQOL with socio-demographics and disease-related factors, and change of HRQOL over time were explored. Comparisons of HRQOL between CRN patients and the general population and among different CRN groups were made. Cross-sectional data were used to develop mapping functions to estimate SF-6D preference scores from FACT-C subscale scores. Third was the application of the health preference scores by CRN stages collected at baseline of the longitudinal study, in combination with survival data extracted from the literature in a Markov model on the cost-effectiveness of different CRC screening strategies (colonoscopy, guaiac and immunochemical fecal occult blood tests) in comparison to no screening in terms of quality-adjusted life-years gained.

Psychometric analysis confirmed that FACT-C had satisfactory reliability, construct validity and responsiveness in Chinese patients Patients with CRN reported worse physical HRQOL but better mental HRQOL and similar health preference score compared to the general population. Disease severity indicated by tumor stage at initial diagnosis was the most significant determinant of HRQOL of CRN patients. Rectal cancer also significantly associated with a decrease in physical HRQOL and health preference scores. Markov modelling showed that immunochemical fecal occult blood (I-FOBT) yearly was the most effective and two-yearly was the most cost-effective screening strategy compared to no screening.