Study objective: The chronically critically ill (CCI)
are a subgroup of critically ill patients who have survived an acute
critical illness but remain profoundly debilitated and ventilator
dependent. We have previously shown that CCI patients have a very high
prevalence of bone hyperresorption. The objective of this present study
was to determine the biochemical response of bone hyperresorption in
CCI patients to treatment with either calcitriol alone or calcitriol
Design: Retrospective survey.
Setting: Respiratory care step-down unit (RCU) at a
tertiary-care teaching hospital.
ventilator-dependent CCI patients transferred from ICUs within the same
institution who had elevated urine N-telopeptide (NTx) levels at RCU
admission, who were treated with either calcitriol alone (n = 44) or
calcitriol and pamidronate (n = 11), and who had urine NTx levels
remeasured following treatment.
Measurements and results: Patients treated with
calcitriol alone had a significant reduction in serum parathyroid
hormone (PTH; 93 ± 145 pg/mL vs 40 ± 28 pg/mL; p = 0.02) but
not in urinary NTx (187 ± 146 nmol bone collagen equivalents[
BCE]/mmol creatinine [Cr] vs 178 ± 123 nmol BCE/mmol Cr,
p = 0.59). In contrast, patients treated with both calcitriol and
pamidronate had a significant decrease in urine NTx at follow-up
(329 ± 238 to 100 ± 85 nmol BCE/mmol Cr; p < 0.01) but not in
serum PTH (36 ± 29 to 53 ± 51 pg/mL; p = 0.44).
Conclusion: The bone hyperresorption of CCI patients is PTH
independent and biochemically responds to treatment with calcitriol and
pamidronate but not calcitriol alone.