Incidence and causes for failure of treatment of women with proven osteoporosis.

The purpose of this study was to examine factors influencing women's compliance with medical therapy for osteoporosis in Israel. The study population consisted of women diagnosed with osteoporosis using a DEXA examination in the year 2000. Medication purchases for a period of 13 months after the exam were analyzed. Data were gathered from the computerized data base of Clalit Health Care Services and phone interviews. Treatment was divided into specific drugs and food additives (preparation of calcium plus vitamin D). Full, intermediate, low and no compliance were defined as >80, 50-80, 25-50 and <25% of treatment days, respectively. In the study, 857 women with a mean age of 73.6 years were enrolled; 581 (67.8%) were interviewed by telephone. Most of women were undereducated and unemployed. Twenty percent did not purchase any specific drug; 4.5% did not purchase any drug or food additive for osteoporosis; 60% were fully or intermittently compliant (by purchasing) with drug therapy. The most frequent single specific drugs purchased were bisphosphanates and SERM: 62.3 and 76.3% purchased bisphosphanates and/or food additives, respectively. Multi-variant analysis showed that predictors of compliance were healthy women, compliant with calcium plus vitamin D preparations, and/or spending more on drugs. Reasons for low or non-compliance were inconsistent recommendations by various physicians and the side effects of specific drugs. The relatively high compliance rate of osteoporosis treatment may be attributed to the increase in awareness of its benefits. The effect of physicians on compliance needs further investigation.