Compliance with drug therapies for the treatment and prevention of osteoporosis.
OBJECTIVE
This study used paid claims data from real-world treatment settings to investigate the impact of hormone replacement therapy (HRT), bisphosphonate and raloxifene on patients with a recorded diagnosis of osteoporosis.


METHODS
Data from a large health insurer were used to identify 58,109 osteoporosis patients who initiated drug therapy for osteoporosis. Multivariate statistical models were developed for duration of therapy, compliance at 1 year, time to discontinuation or a change in therapy, health care costs and risk of fracture over 1 year.


RESULTS
One-year compliance rates were below 25% for all osteoporosis therapies. The mean unadjusted duration of continuous therapy was 221 days for raloxifene, 245 days for bisphosphonate, 262 for estrogen-only and 292 days for estrogen plus progestin. Raloxifene patients were consistently less compliant than estrogen-only patients after adjusting for differences in patient characteristics. Estrogen plus progestin patients were generally more compliant while bisphosphonate did not differentiate from estrogen-only. Compliance reduced the risk of hip fracture (o.r. = 0.382, P < 0.01) and vertebral fracture (o.r. = 0.601, P < 0.05). Compliant patients used fewer physicians services (-US dollars 56, P < 0.0001), hospital outpatient services (-US dollars 38, P < 0.05) and hospital care (-US dollars 155, P < 0.01). Bisphosphonate patients were twice as likely as estrogen-only patients to experience vertebral, Colles and other fractures and experienced higher health care costs (+US dollars 420, P < 0.01). The effectiveness of both raloxifene and bisphosphonate medications relative to estrogen-only improved significantly with the age of the patient.


CONCLUSIONS
Compliance with drug therapies for osteoporosis over 1 year is poor leaving patients at risk for fractures and higher health care costs.
McCombs
Jeffrey S
JS
Department of Pharmaceutical Economics and Policy, School of Pharmacy, University of Southern California, Los Angeles, CA, USA. jmccombs@usc.edu
Thiebaud
Patrick
P
McLaughlin-Miley
Connie
C
Shi
Jinhai
J
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D004164:Diphosphonates / Q000008:administration & dosage / Q000191:economics; D015914:Estrogen Replacement Therapy / Q000191:economics / Q000379:methods / Q000706:statistics & numerical data; D004967:Estrogens / Q000008:administration & dosage / Q000191:economics; D005260:Female; D050723:Fractures, Bone / Q000191:economics / Q000453:epidemiology* / Q000517:prevention & control; D017048:Health Care Costs; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010024:Osteoporosis / Q000150:complications / Q000188:drug therapy* / Q000191:economics / Q000517:prevention & control*; D010349:Patient Compliance / Q000523:psychology*; D020849:Raloxifene Hydrochloride / Q000008:administration & dosage / Q000191:economics; D012189:Retrospective Studies; D012307:Risk Factors
D004164:Diphosphonates; D004967:Estrogens; D020849:Raloxifene Hydrochloride