Evaluation of persistence and adherence to teriparatide treatment in patients affected by severe osteoporosis (PATT): a multicenter observational real life study

Introduction. Osteoporosis is a chronic condition leading to an increased risk of developing fractures, with high morbidity and mortality in aging population. Efficacy of anti-osteoporotic treatment is based on drug potency but also on compliance and persistence to treatment regimen, which is very low, as already described for other diseases. Teriparatide (TPTD) is the first anabolic agent developed for the treatment of osteoporosis. Since it appears that persistence to Teriparatide declines over time, aim of this pilot multicenter observational study was to evaluate persistence and adherence to TPTD (20 mu g daily injection regimen for 18 months) treatment (PATT) in patients affected by severe osteoporosis in an every day clinical practice. Methods. Patients affected by severe osteoporosis were selected among those who referred to 5 different specialized centers for osteoporosis in North, Center and South of Italy. A sample of 475 women with severe postmenopausal osteoporosis treated with TPTD in accordance to the Italian osteoporosis guidelines was included. At the beginning of TPTD treatment patients were instructed on the use of the device by the referring specialist of the center, a resident fellow or a nurse. Bone biochemical markers were evaluated the same morning and after 1, 3, 6, 12 and 18 months. Patients were visited at time 0 and after 6, 12 and 18 months for clinical follow up. Results. The results included observations of 441/ 475 patients (98% women) who completed the 18 months treatment; mean age for women was 73 +/- 8 and for men 65 +/- 9. After 6 months of TPTD treatment persistence was of 89,79%, 87,75% after 12 months and 86,85% after 18 months. Adherence was of 100% at 6,12 and 18 months. Total dropouts were 13,15% (71/441), which was usually higher within the first 6 months of TPTD treatment. Most common adverse events (arthralgies 2,7%, dizziness 1,8%, migraine 1,8%, depression 1,6%, hypertension 1,1%) were reported in 62/441 patients (14%) of patients, but were not reason for stopping treatment. Conclusions. The persistence and adherence to TPTD treatment obtained in this multicenter observational real life study was very high as compared to studies performed by others. These encouraging results suggest that different key factors such quality of information, frequency of visits, motivations given to patients, opportunity to call the doctor might play a pivotal role in the high persistence and adherence to TPTD treatment obtained in our study and need to be carefully considered before prescribing chronic anti-osteoporotic therapy.