Hyperglycemia, symptoms, and symptom clusters in colorectal cancer survivors with type 2 diabetes

The purpose of the study was to compare the individual and total number of symptoms and explore symptom clusters by hyperglycemia status in colorectal cancer survivors (CRCS) with diabetes (type 2).A retrospective cohort study was conducted, whereby symptom data were extracted from clinical notes in electronic health records. CRCS (stage II or III) diagnosed between 2007 and 2017 who had diabetes and at least one HbA1c within 8 months of initial chemotherapy were included. Zero-inflated negative binomial regression analysis was used to examine total symptoms by hyperglycemia status (hyperglycemia versus no hyperglycemia). Exploratory factor analysis was conducted to identify symptom clusters.Two hundred forty-three CRCS met inclusion criteria. CRCS with hyperglycemia (HbA1c ≥ 6.5%) had greater individual symptoms (fatigue and depression) and total number of symptoms than those with no hyperglycemia. Two distinct symptom clusters, with five (nausea, vomiting, constipation, fatigue, and peripheral neuropathy) and two symptoms (anxiety and depression), were identified among CRCS with hyperglycemia.These findings indicate that CRCS with diabetes and hyperglycemia had more symptoms and two distinct symptom clusters compared to those with no hyperglycemia. Prospective research studies are needed to examine the role of hyperglycemia in symptoms among CRCS with diabetes. Understanding hyperglycemia's influence is important as it is a modifiable risk factor towards which prevention and intervention can be directed, potentially mitigating symptoms and symptom clusters and improving outcomes for CRCS with diabetes.