Drug-induced osteoporosis/osteomalacia: analysis in the French and Spanish pharmacovigilance databases

Osteomalacia and osteoporosis are two metabolic bone disorders that increase the risk of fracture due to several causes. In terms of drugs, apart from corticosteroids, which are known to induce bone disorders, several other drugs used in chronic disease management have also been linked with an increased risk of osteoporosis and osteomalacia.

The aim of this study was to describe spontaneous reports of drug-induced osteoporosis and osteomalacia in the French (FPVDB) and Spanish (SPVDB) pharmacovigilance databases.

Data were provided by the FPVDB and SPVDB. All reports of osteoporosis and osteomalacia recorded from 1985 up to 31 December 2015 inclusive were selected. Taking the time to onset of bone loss into account, all cases occurring in less than 1 month were excluded.

A total of 369 reports (44 cases of osteomalacia, 325 cases of osteoporosis) were registered in the FPVDB and 64 (22 cases of osteomalacia, 42 cases of osteoporosis) in the SPVDB. In France, the top 5 drugs involved in the onset of osteoporosis were corticosteroids accounting for approximately half of the reports (n = 170) followed by systemic antiviral (n = 87), antacid (n = 29), antiepileptic (n = 27) and antithrombotic (n = 24) drugs. The 2 main classes of drugs implicated in osteomalacia were systemic antiretroviral drugs for half of the reports (n = 21) and antiepileptic drugs (n = 15). In Spain, corticosteroids were involved in 35.7% of reported cases of osteoporosis (n = 15) followed by systemic antiviral drugs (n = 12). There was no spontaneous report for antacid drugs. For osteomalacia, the 2 main drug classes were systemic antiretroviral drugs (n = 18, 81.8%) followed by antiepileptics (n = 2, 9.0%). In both countries, concomitant administration of systemic corticosteroids with other suspected drugs did not significantly modify the time to onset of drug-induced osteoporosis.

Despite some differences between the French and Spanish PVDBs, our data consistently show that bone loss is not only restricted to glucocorticoids but also involves antivirals, antiepileptic drugs, antacid drugs or antidepressants. Further analysis might prove useful in exploring the characteristics of drug-induced bone loss on a larger scale.