Determinants of sleep quality in 5835 individuals living with and beyond breast, prostate, and colorectal cancer: a cross-sectional survey

Purpose The present study aimed to quantify the level of sleep problems in 5835 breast, prostate, and colorectal cancer survivors, and explore a number of potential determinants of poor sleep quality in the present sample. BMI, diet, and physical activity were of particular interest as potential determinants. Methods Participants who completed the ‘Health and Lifestyle after Cancer’ survey were adults who had been diagnosed with breast, prostate, or colorectal cancer (mean time since cancer diagnosis was 35.5 months, SD=13.56). Sleep quality was assessed using the Pittsburgh Sleep Quality Index. BMI was calculated from self-reported height and weight. Participants were categorised as meeting/not meeting the World Cancer Research Fund (WCRF) recommendations for fibre, fruit and vegetables, added sugar, red meat, processed meat, fat, alcohol, and physical activity. Analyses accounted for demographic and clinical factors. Results Fifty-seven percent of those with sleep data were classified as poor sleepers (response rate 79%). Being female, having a higher number of cancer treatments, more comorbid conditions, and being more anxious/depressed increased the odds of being a poor sleeper. After adjustment for these factors, there were no associations between diet/alcohol/physical activity and sleep. However, BMI was associated with sleep. Individuals in the overweight and obese categories had 22% and 79% higher odds of being poor sleepers than individuals in the underweight/healthy weight category, respectively. Conclusions The findings suggest that there may be a need to develop sleep quality interventions for cancer survivors with obesity. Even after adjustment for multiple clinical and demographic factors, BMI (particularly obesity) was associated with poor sleep. Thus, researchers and health professionals should find ways to support individuals with overweight and obesity to improve their sleep quality. Implications for Cancer Survivors The present findings highlight that poor sleep is a common issue in cancer survivors. Interventions seeking to improve outcomes for cancer survivors over the longer term should consider sleep quality.