Seizures Associated With Bone Density Conservation Agents.

Objective: The purpose of this review is to discuss the existing literature regarding patients who have experienced seizures after administration of a bone density conservation agent (BDCA).

Data sources: A comprehensive literature review was performed between September and October 2021 using the following keywords: osteoporosis/drug therapy, seizures/chemically induced, hypercalcemia, hypocalcemia, osteoporosis, seizure risk, osteoclast medication, seizures, bisphosphonates, risedronate, zoledronic acid, pamidronate, denosumab, Prolia, Xgeva, calcitonin, BDCAs.

Study selection and data extraction: A total of 90 articles were identified, but only 6 articles met prespecified inclusion and exclusion criteria. These articles included 4 case reports, 1 case series, and 1 retrospective cohort study.

Data synthesis: Two case reports and 1 case series described the occurrence of seizures with the use of zoledronic acid. One case report described the occurrence of seizures with the use of alendronate, 1 retrospective cohort study with the use of denosumab, and 1 case report with the use of calcitonin. The articles displayed a variety of contributing factors that could have caused seizures including those with a prior history of seizures, calcium or vitamin D deficiency prior to starting therapy, a history of gastrectomy impairing glucose homeostasis, or concurrent infection.

Conclusion: While there is not a direct link to BDCA causing seizures, the hypocalcemic effect may be severe enough in some patients to precipitate a seizure. The correction of underlying conditions and electrolyte disturbances should be addressed before initiating a BDCA. Further studies are needed to better explore the relationship between BDCA and seizures.