Lack of an association between gallstone disease and bilirubin levels with risk of colorectal cancer: a Mendelian randomisation analysis.

BACKGROUND: Epidemiological studies of the relationship between gallstone disease and circulating levels of bilirubin with risk of developing colorectal cancer (CRC) have been inconsistent. To address possible confounding and reverse causation, we examine the relationship between these potential risk factors and CRC using Mendelian randomisation (MR). METHODS: We used two-sample MR to examine the relationship between genetic liability to gallstone disease and circulating levels of bilirubin with CRC in 26,397 patients and 41,481 controls. We calculated the odds ratio per genetically predicted SD unit increase in log bilirubin levels (ORSD) for CRC and tested for a non-zero causal effect of gallstones on CRC. Sensitivity analysis was applied to identify violations of estimator assumptions. RESULTS: No association between either gallstone disease (P value = 0.60) or circulating levels of bilirubin (ORSD = 1.00, 95% confidence interval (CI) = 0.96-1.03, P value = 0.90) with CRC was shown. CONCLUSIONS: Despite the large scale of this study, we found no evidence for a causal relationship between either circulating levels of bilirubin or gallstone disease with risk of developing CRC. While the magnitude of effect suggested by some observational studies can confidently be excluded, we cannot exclude the possibility of smaller effect sizes and non-linear relationships.

Developing and piloting a nurse-led model of follow-up in the multidisciplinary management of colorectal cancer.

One of the main challenges of colorectal cancer follow-up is the detection of early disease in order to influence survival and improve outcome. Yet, the benefits of follow-up are not only related to survival. It is well documented that patients can experience an array of problems following colorectal cancer surgery which impact upon quality of life, therefore symptom management plays an important part in the overall spectrum of follow-up care. In addition, there is emerging evidence to suggest that clinical nurse specialists are well placed in the multidisciplinary team to co-ordinate such follow-up programmes. This paper reports on a pilot study designed to assess the feasibility of a follow-up programme led by nurse specialists for patients with colorectal cancer. Key outcome areas were adherence to an agreed follow-protocol, quality of life, patient and clinician satisfaction and a cost-analysis of the new model. The study was conducted over one year with 60 patients. This redesign resulted in a smoother pathway of follow-up care, improved quality of life and acceptance to both patients and clinicians alike. The introduction of a nurse-led follow-up model is expected to demonstrate cost savings over a 3 year rolling follow-up programme.