Background and objective: Reduction of bone mineral density (BMD) is a complication of cystic fibrosis (CF) which is observed in parallel to the increment of life expectancy in these patients. The aim of this study was to analyze the evolution of BMD following the application of a protocol for the prevention and treatment of osteoporosis.
Patients and method: We performed a multidisciplinary prospective study in 21 adult patients with CF with a mean age of 24.3 (r: 19-44) years. We evaluated BMD results depending on the treatment schedule, and the annual relative change of BMD percentage was correlated with changes observed in respiratory function, corporal mass index (CMI), Brasfield radiologic score and Shwachman clinical score for a 3 years follow up period. Three regimens of treatment were applied: general measurements, supplementation of calcium and vitamin D, and 10 daily mg of alendronate plus calcium and vitamin D supplements.
Results: Basal assessment showed that 14.2% of CF patients had a marked diminution of bone mass with respect to an age and sex matched control population, with a Z score of < -2 DE in lumbar vertebral and/or total femur. Another 38% showed a lessening of Z score between -1 and -2.5 DE. We observed a progressive annual reduction of BMD in all the anatomic areas analyzed: -0.52% (1.87) in lumbar spine, -1.17% (1.91) in total femur and -2.16% (2.65) in neck femur. The hip BMD annual decrement was related to that observed in FEV1. Only patients treated with alendronate did not suffer progressive BMD lose. Treatment with a combination of calcium, vitamin D and alendronate was more efficient in hip BMD than calcium plus vitamin D alone (p < 0.05). Also, this combination was better than no treatment at hip and femoral neck levels (p < 0.05).
Conclusions: Our work confirms that Spanish young adults patients with CF show low control matched BMD, and that it even worsens at follow-up. This decrement is not adequately halted with preventive treatment with supplements of calcium and vitamin D, and only patients treated with alendronate show increments of their BMD.