Response to Letter to the Editor From Riahi and Gruntmanis: “Inpatient Zoledronic Acid and Integrated Orthopedic and Fracture Liaison Services Improve Osteoporosis Treatment Rates” Free

We highly appreciate the 2 important comments made by Riahi and Gruntmanis (1).

Zoledronic acid (ZA) reduces serum calcium level and can cause significant hypocalcemia, especially among patients with vitamin D deficiency. In general, intravenous bisphosphonates for patients with osteoporotic fragility fracture have been administered in the outpatient setting, typically 2 weeks after surgery (2, 3). This is partly due to concerns of hypocalcemia, which could be worsened by vitamin D deficiency, in the acute postoperative setting (3). Vitamin D deficiency is common among patients seen by the Massachusetts General Hospital Fracture Liaison Service. Our data from a cohort of 1196 consecutive patients showed that 25.4% of them had a 25-hydroxy vitamin D (25OHD) level of 19 ng/mL or less (unpublished data). All patients with 25OHD > 20 ng/mL, regardless of the decision for inpatient ZA (IP-ZA), were treated with cholecalciferol 1000 to 2500 international units daily along with calcium (as calcium citrate or carbonate) 650 to 1000 mg daily unless contraindicated or declined by the patient. Among patients with serum 25OHD of 20 ng/mL or above and on the above supplementations, IP-ZA was not associated with symptomatic hypocalcemia in the acute postfracture setting (data under review). For patients with 25OHD of <20 ng/mL, we have a loading/repletion protocol, the outcome of which is currently being analyzed.

In terms of outpatient follow-up, as pointed out in the letter, our data demonstrated that patients with recent fragility fractures often experience significant difficulty in achieving timely and regular outpatient follow-up, even when selected for their presumed ability to do so (4). It is precisely for this reason that prompt initiation of treatment during the index fracture hospitalization offers a unique opportunity to improve osteoporosis treatment rates for this particularly at-risk population. As suggested, our data support the assertion that “we should consider more patients for inpatient treatment of osteoporosis” and specifically that fracture liaison service–managed IP-ZA may be a particularly efficient way of achieving this goal. We are currently analyzing the data further in order to better assess IP-ZA's safety profile and will continue to assess long-term outcomes in our growing cohort.

Funding

Not applicable.

Disclosures

W.F.: no conflict of interest and nothing relevant to current study to disclose. B.Z.L.: no conflict of interest and nothing relevant to current study to disclose. M.B.B.: Grants: Rheumatology Research Foundation Clinician Scholar Educator Award; Genentech, Cumberland, Inc., Corbus. Honoraria: The Merck Manual, American Board of Internal Medicine. Board of Directors: American College of Rheumatology.

References

Abbreviations

 
• 25OHD

  25-hydroxy vitamin D

 
• IP

  inpatient

 
• ZA

  zoledronic acid