Hyperglycaemia and reduced risk of prostate cancer

Hyperglycemia, Classified with Multiple Biomarkers Simultaneously in Men without Diabetes, and Risk of Fatal Prostate Cancer

The association between hyperglycemia and prostate cancer risk is inconsistent, and its association with prostate cancer mortality is understudied. Thus, we investigated the association between hyperglycemia and prostate cancer risk and mortality using multiple biomarkers simultaneously to classify hyper- and normoglycemia. We conducted a prospective analysis of 5,162 cancer-free men attending visit 2 (1990-1992) of the Atherosclerosis Risk in Communities (ARIC) study followed for total (N = 671) and lethal (N = 69) prostate cancer incidence and prostate cancer mortality (N = 64) through 2012. Men without diagnosed diabetes were classified as normo- or hyperglycemic using joint categories of fasting glucose, glycated hemoglobin, and glycated albumin (or fructosamine) defined by clinical or research cutpoints. We evaluated the multivariable-adjusted association of hyperglycemia with prostate cancer incidence and mortality using Cox proportional hazards regression; men with diagnosed diabetes were included as a separate exposure category. Among 4,753 men without diagnosed diabetes, 61.5% were classified as having hyperglycemia (high on ≥1 biomarker). HbA1c and glycated albumin together classified 61.9% of 1,736 men with normal fasting glucose as normoglycemic. Compared with men who were normal on all three biomarkers, men who were high on ≥1 biomarker had an increased risk of lethal [HR, 2.50; 95% confidence interval (CI), 1.12-5.58] and fatal (HR, 3.20; 95% CI, 1.26-8.48) disease, but not total prostate cancer incidence (HR, 0.98; 95% CI, 0.81-1.20); associations were similar including fructosamine instead of glycated albumin. Our findings indicate hyperglycemia is associated with an increased risk of lethal and fatal prostate cancer, but not total prostate cancer incidence.