Effect of the mode of calcitriol administration on PTH-ionized calcium relationship in uraemic patients with secondary hyperparathyroidism.

To assess the effect of the different modes of calcitriol administration on PTH-ionized calcium relationship we conducted a prospective clinical trial in 33 patients on chronic haemodialysis with secondary hyperparathyroidism (four times upper normal limit intact PTH) who were randomly assigned, with stratification to PTH levels, to receive daily oral, intermittent oral, or intermittent intravenous calcitriol at the same dose of 0.045 micrograms/kg/weekly. PTH-iCa curves were generated by inducing hypo- or hypercalcaemia in sequential haemodialysis 1 week apart, before and after 10 weeks on treatment. All patients were dialysed against a dialysate calcium concentration of 2.5 mEq/l throughout the study period. After drop-outs, 26 patients completed the study: 11 on intravenous calcitriol (mean basal PTH +/- SD: 666 +/- 280 pg/ml), eight on intermittent oral calcitriol (mean basal PTH: 831 +/- 361), and seven on daily oral calcitriol (mean basal PTH: 719 +/- 280). Serum ionized calcium and phosphorus significantly increased in intravenous and daily oral groups after calcitriol treatment, but not in the intermittent oral group. Basal PTH did not significantly change in the three groups after 10 weeks on treatment. Maximal PTH significantly decreased in intravenous group (1449 +/- 660 versus 1122 +/- 691 pg/ml, P = 0.0085) and at the limit of statistical significance in the intermittent oral group (1701 +/- 774 versus 1445 +/- 634, P = 0.12), but it did not change in the daily oral group. Minimal PTH did not modify in the three groups. In all three groups, a shift to the right in the PTH-iCa relationships were observed, with significant changes in the set point of calcium.(ABSTRACT TRUNCATED AT 250 WORDS)

Bisoprolol and nifedipine SR in the treatment of hypertension in the elderly.

Forty outpatients (11 men and 29 women) aged between 65 and 85 years (mean age of 68 years) with mild to moderate hypertension [mean systolic/diastolic blood pressure (SBP/DBP) after 2 weeks on placebo of 175/102 mm Hg] were included in a randomized, double-blind, parallel-group study to compare the efficacy and tolerance of 10 mg of bisoprolol once daily (o.d., n = 20) and 20 mg of nifedipine sustained release (SR) b.i.d. (n = 20) during 4 weeks of treatment. SBP and DBP were significantly reduced compared to baseline with both treatments. There was no significant difference in efficacy between the two treatments after 2 and 4 weeks. After 2 weeks, the number of patients with normalized DBP (< or =90 mm Hg) was higher with bisoprolol than with nifedipine, this difference no longer being present after 4 weeks. Resting heart rate was significantly reduced with bisoprolol from 78+/-8 to 68+/-9 beats/min after 4 weeks, but there was no change in heart rate with nifedipine. Adverse events were reported by 6 patients on bisoprolol (20 events) and 12 patients on nifedipine (51 events) and the overall tolerance of bisoprolol was considered to be significantly better than that of nifedipine. Because bisoprolol is equally effective when administered once daily in comparison with nifedipine SR, which has to be given twice daily, and since bisoprolol exhibits a better tolerance, this beta-blocker appears to be a useful drug of first choice for the treatment of elderly hypertensive patients.