Are we overconcerned about secondary hyperparathyroidism and underestimating the more common secondary hypoparathyroidism in our dialysis patients?

OBJECTIVES

The aim of the study was to determine the prevalence of hyper and hypo-parathyroid state in prevalent dialysis patients. The second part of the study was to look for the prevalence of vascular calcification (abdominal aortic) and factors predicting calcification in these patients.

METHODS

All adult patients, who were more than 1 month on dialysis, were included in the study. A total of 68 patients, of which 75% were on hemodialysis and 25% on peritoneal dialysis, were finally studied. Patients' parathyroid status was defined as per target recommendation of KDOQI--hypoparathyroid with iPTH < or = 150 pg/ml and hyperparathyroid with iPTH > 300 pg/ml. Vascular calcification was determined by X ray of lateral lumbar spine to look for abdominal aortic calcification (AAC). The AAC was scored as validated. The prevalence of hyper- and hypoparathyroidism in dialysis patients was determined as percentage of total dialysis patients. The prevalence of AAC and factors predicting it was analyzed by 'univariate' and 'multiple logistic regression analyses.

RESULTS

The mean age of patients was 50.04 +/- 14.15 years, 58.82% were males and 42.64% were diabetics. Mean duration of dialysis was 22.36 +/- 19.17 months. Hyperparathyroidism was seen in only 27.94% of all dialysis patients, while hypoparathyroidism was in 45.58%. Abdominal aortic calcification was seen in 79.41% of overall patients and 13.23% had significant calcification (score 7-24). On univariate analysis, age (0.000) and iPTH (0.03) were the only variables predicting AAC and on logistic regression analysis, age was the only independent predictor of abdominal aortic calcification (p = 0.002, OR 1.11, CI 1.038-1.186).

CONCLUSION

Hypoparathyroidism is more common (46%) in our dialysis patients as compared to hyperparathyroidism (28%). There is high prevalence of vascular (abdominal aortic) calcification (80%) in our dialysis patients.