Tomoko Sakai 1, Shiho Honzawa 2, Makiko Kaga 2, Yuji Iwasaki 2, Tatsuo Masuyama 2
Objectives: We assessed the severity and pathology of osteoporosis in children and adults with severe motor and intellectual disabilities (SMID) by evaluating bone enzymes, by which we aimed to determine adequate treatment approaches for preventing fractures.
Methods: Ninety patients (44 men, 46 women; mean age, 34.5 years) underwent bone quality assessment. Quantitative ultrasonography (QUS) was used to measure the T-score and Z-score of the calcaneus, and blood tests were used to measure bone-specific alkaline phosphatase and tartrate-resistant acid phosphatase 5b levels as bone formation and resorption markers, as well as calcium, phosphorous, and parathyroid hormone levels as routine examination.
Results: Bone formation and resorption marker levels were within normal ranges in adults, although they were high during the growth period in children and adolescents and in elderly women. Patients receiving tube feeding showed a significantly lower Z-score than those without tube feeding. Tube feeding was a significant factor for the Z-score, whereas age, vitamin supplements, and anti-epileptic drugs were not.
Conclusions: The severity of osteoporosis in SMID started during the growth period and seems to be caused by a lack of an effective increase in bone mineral density. Any treatment should be started during the growth period. More study about tube feeding is needed.