The risk of osteonecrosis of the jaws in Taiwanese osteoporotic patients treated with oral alendronate or raloxifene.
BACKGROUND
This study aimed to explore the possible association between osteonecrosis of the jaws (ONJ) and oral alendronate or raloxifene used for osteoporosis and to estimate its absolute and attributable risks in the Taiwanese population.


METHODS
Using an electronic medical records system and manual confirmation of ONJ, we identified patients who began taking alendronate or raloxifene for osteoporosis and developed ONJ between January 2000 and April 2012.


RESULTS
The incidence of ONJ associated with oral alendronate for the management of osteoporosis began after 1 year of drug exposure and progressively increased with longer durations of therapy, specifically from 0.23% to 0.92% as the duration of treatment went from 2 years to 10 years. The overall frequency of ONJ related to oral alendronate over a 12-year period was 0.55%. The incidence rate of ONJ attributed to alendronate exposure was 283 per 100 000 persons per year. On multivariate Cox proportional analysis, adjusting for the potential confounders, alendronate remains an independent predictor for ONJ occurrence [hazard ratio 7.42 (1.02-54.09)] compared with raloxifene. Advanced age, drug duration, and coexisting diabetes and rheumatoid arthritis are contributing factors to the development of oral alendronate-related ONJ.


CONCLUSIONS
We provided the evidence to support the association of ONJ with oral alendronate used in the treatment or prevention of osteoporosis.
Division of Endocrinology and Metabolism (W.-Y.C., W.-S.Y., K.-S.T.) and Department of Internal Medicine (W.-Y.C., J.-Y.C., W.-S.Y., J.-M.J.J., K.-S.T.), National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan; Department of Laboratory Medicine (W.-Y.C., K.-S.T.), and Division of Oral and Maxillofacial Surgery (J.-J.L.), Department of Dentistry, National Taiwan University Hospital, Taipei 10002, Taiwan; and Graduate Institute of Clinical Medicine (W.-Y.C., J.-Y.C., W.-S.Y.), College of Medicine, National Taiwan University, Taipei 10002, Taiwan.
Wei-Yih
WY
Chiu
Jung-Yien
JY
Chien
Wei-Shiung
WS
Yang
Jyh-Ming Jimmy
JM
Juang
Jang-Jaer
JJ
Lee
Keh-Sung
KS
Tsai
D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D019386:Alendronate / Q000008:administration & dosage* / Q000009:adverse effects; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000453:epidemiology*; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000188:drug therapy* / Q000453:epidemiology*; D020849:Raloxifene Hydrochloride / Q000008:administration & dosage* / Q000009:adverse effects; D012189:Retrospective Studies; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology
D050071:Bone Density Conservation Agents; D020849:Raloxifene Hydrochloride; D019386:Alendronate