Effects of intranasal salmon calcitonin in juvenile idiopathic arthritis: an observational study.

The aim of this study was to follow the changes in bone mineral density (BMD) and biochemical markers of bone turnover in 10 children (7.5-17.5 years of age) with severe juvenile idiopathic arthritis (JIA), during a 3-year therapy with salmon calcitonin (100 IU/day 2 months on and 2 off for a year and 200 IU/day for 2 years) and calcium (500 mg/day). All patients were functional classes III and IV and were measured at yearly intervals with a dual photon absorptiometer at the lumbar spine. The changes observed were 7.2-9.5% per year for BMD and 2.0-6.0% for volumetric bone mineral density (BMDvol). The bone resorption markers showed significant decreases after a year's treatment (Pyr/Cr from 175+/-15 to 108+/-15 nm/mm, P < 0.001, Pyr-D/Cr from 24.3+/-3.5 to 13.3+/-1.9 nm/mm, P < 0.05, and OHPr/Cr from 57.4+/-11 to 35.1+/-8.4 microg/mg) and smaller changes thereafter. No significant changes were observed in the bone formation markers of osteocalcin and alkaline phosphatase. Serum iPTH, the vitamin D metabolites, and calcium concentrations fluctuated within normal, while calcium excretion increased from 0.3+/-0.1 to 1.9+/-0.4 mg/kg/24 hours, P < 0.001. In conclusion, the present study, despite its limitations of not being placebo controlled, shows possible beneficial effects of intranasal calcitonin on bone resorption and pain relief in JIA patients.