Secondary hyperparathyroidism is a common complication of renal failure. The exact prevalence in chronic hemodialysis patients in not known. We evaluated 122 patients who were receiving maintenance hemodialysis for at least 12 months in 2 dialysis centers in mid Michigan. Seventy-eight percent of the patients had iPTH above 200 pg/mL (mean 481 pg/mL), 19% had iPTH within the accepted normal range (mean 155 pg/mL), while 3% had level below 100 (mean 53 pg/mL). Phosphate, calcium, calcium phosphate product, age and time on dialysis are the important factors correlating with elevated iPTH. There was no significant difference in iPTH between diabetic and nondiabetic patients with mean iPTH of 403 pg/mL and 407 pg/mL respectively. Black patients had a statistically significant elevated iPTH compared with white patients with a mean iPTH of 438 pg/mL and 283 pg/mL respectively (p < or = 0.004). Factors that predict the response to vitamin D therapy need to be evaluated to help reduce the high prevalence of secondary hyperparathyroidism. The patterns of bone disease in black patients need to be evaluated to further define the accepted normal iPTH range for this population.