PTH and prostate cancer: Among prostate cancer patients, vitamin D levels correlated positively with age (r = 0.12, P < 0.02), and were negatively associated with BMI (r = −0.13, P = 0.003), glucose (r = −0.12, P < 0.007), HbA1C (r = −0.16, P = 0.001), and PTH (r = −0.21; P < 0.0001).