Positive impact of compliance to strontium ranelate on the risk of nonvertebral osteoporotic fractures.
CONCLUSIONS
Adherence is now one of the major issues in the management of osteoporosis. This paper relates the relationship existing between adherence to strontium ranelate and the risk of subsequent nonvertebral fracture among postmenopausal women with osteoporosis.


BACKGROUND
The aim of this study is to investigate compliance to strontium ranelate (SR) therapy and the impact of compliance on the risk of nonvertebral fractures among women with osteoporosis.


METHODS
This study was a post-hoc analysis of pooled data from two international, phase III, randomized, placebo-controlled, double-blind studies (the Spinal Osteoporosis Therapeutic Intervention and Treatment Of Peripheral Osteoporosis). A nested case-control study was performed in the strontium ranelate-treated population. Compliance was quantified using the medication possession ratio (MPR).


RESULTS
Two hundred eighty-five nonvertebral fracture cases (hip fx n = 70; major nonvertebral fx n = 213) were identified and matched to 1,425 controls. The mean MPR was 86.8% for controls and 82.6% for cases (p < 0.001). Women who were compliant to SR had a 38% reduction in all nonvertebral fractures compared with those who were not (OR = 0.62; 95%CI[0.47-0.81; p < 0.001). Considering hip fractures only, the risk was reduced by 50% for compliant patients compared to noncompliant patients (OR = 0.50; 95%CI[0.28-0.88]; p < 0.05).


CONCLUSIONS
Our analyses emphasize the importance of good compliance to treatment in order to reduce the risk of osteoporotic fractures. In particular, there was a greater reduction in the risk of nonvertebral and hip fractures with increase compliance.
Rabenda
V
V
Department of Public Health, Epidemiology and Health Economics, University of Liège, CHU-Bât. B23, 4000, Liège, Belgium. veronique.rabenda@ulg.ac.be
Reginster
J-Y
JY
D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008875:Middle Aged; D009942:Organometallic Compounds / Q000627:therapeutic use*; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000503:physiopathology / Q000517:prevention & control*; D013876:Thiophenes / Q000627:therapeutic use*; D016896:Treatment Outcome; D016903:Drug Monitoring
D050071:Bone Density Conservation Agents; D009942:Organometallic Compounds; D013876:Thiophenes; C081587:strontium ranelate