title: Assessing the risk of osteonecrosis of the jaw due to bisphosphonate therapy in the secondary prevention of osteoporotic fractures.
abstract: CONCLUSIONS
  There is evidence that the use oral bisphosphonates can lead to osteronecrosis of the jaws (ONJ). Although the occurrence of ONJ appears rare among oral bisphosphonates (BPs) users, it is important to know that it exists and can be opportunely minimized.
  
  
  BACKGROUND
  The purpose of this study is to evaluate the association between BPs prescribed for the secondary prevention of osteoporotic fractures and the occurrence of ONJ.
  
  
  METHODS
  An Italian record linkage claims database with a target population of around 18 million individuals (6 million over 55 years of age) constituted the data source. We conducted a nested case-control study within a cohort of individuals aged 55+ years old, who were discharged from hospitals with a primary diagnosis of incident osteoporotic fracture. The date related to the discharge diagnosis of ONJ was the index date. Conditional logistic regression for matched data was fitted to estimate the odds ratio (OR) along with 95 % confidence intervals (95 % CI) for the likely association between use of BPs and the risk of ONJ.
  
  
  RESULTS
  Any one of the 61 ascertained cases of ONJ (incidence rate, 36.6 per 100,000 person-years) was matched to 20 controls for a total of 1120 controls. When the exposure to BPs was modeled according to recency (i.e., exposure time window prior to the index date) of use, the adjusted OR (95 % CI) for current users was 2.8 (1.3-5.9) against never users. The cumulative use of BPs has shown to increase the incidence of ONJ among patients with primary osteoporotic fractures, although not statistically significant risk has been observed.
  
  
  CONCLUSIONS
  Although the risk of BP-related ONJ appears low in non-oncological indications, it is important to be aware that it exists and to know how it may be predicted and possibly minimized.
authors.affiliation: Regional Agency for Healthcare Services of Tuscany, Florence, Italy. francesco.lapi@unifi.it
authors.forename: F
authors.initials: F
authors.lastname: Lapi
authors.forename: F
authors.initials: F
authors.lastname: Cipriani
authors.forename: A P
authors.initials: AP
authors.lastname: Caputi
authors.forename: G
authors.initials: G
authors.lastname: Corrao
authors.forename: A
authors.initials: A
authors.lastname: Vaccheri
authors.forename: M C
authors.initials: MC
authors.lastname: Sturkenboom
authors.forename: M
authors.initials: M
authors.lastname: Di Bari
authors.forename: D
authors.initials: D
authors.lastname: Gregori
authors.forename: F
authors.initials: F
authors.lastname: Carle
authors.forename: T
authors.initials: T
authors.lastname: Staniscia
authors.forename: A
authors.initials: A
authors.lastname: Vestri
authors.forename: M
authors.initials: M
authors.lastname: Brandi
authors.forename: V
authors.initials: V
authors.lastname: Fusco
authors.forename: G
authors.initials: G
authors.lastname: Campisi
authors.forename: G
authors.initials: G
authors.lastname: Mazzaglia
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000453:epidemiology / Q000209:etiology*; D050071:Bone Density Conservation Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D016022:Case-Control Studies; D004164:Diphosphonates / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008498:Medical Record Linkage; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000517:prevention & control*; D018570:Risk Assessment / Q000379:methods
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates