The use of historical and anthropometric data as risk factors for screening of low mBMD & MCI.

To evaluate the risk factors which affect bone loss in screening for osteoporosis, interview of anamnestic data (age, marriage status, pregnancies, menopausal age, intake of calcium, vegetables, protein and coffee, excessive use of alcohol and smoking, sedentary habits, family history), medical data, surgical data, followed by measurement of anthropometric variables [weight, height, antero-posterior (AP) thickness at xiphoid level], blood examination (calcium, inorganic phosphorus, alkaline phosphatase), both postero-anterior (PA) hands and lateral thoraco-lumbar radiography were done in 1,182 normal volunteers aged 17-83. From PA hands radiographs, metacarpal bone mineral density (mBMD) and metacarpal index (MCI) were measured by computed X-ray densitometry (CXD) (Bonalyzer, Teijin Ltd., Tokyo). The results showed that the mean of menopausal age in Thai females was 48.86 +/- 3.09 years ranging from 39 to 55 years. The average number of children in their family was 2.10. Correlation among anthropometric variables, AP thickness was positive linear correlation to weight/height ratio (r = 0.7878, p-value < 0.005). Weight, AP thickness and body mass index (BMI) significantly increased with aging (r = 0.2456, 0.4489 and 0.3484, p-value < 0.005, 0.001 and < 0.005), but decreased with height (r = -0.1030, p-value = 0.001). Lower mBMD and MCI were associated with increased age, married female, increased pregnancies, increased AP thickness, decreased vegetable intake, increased protein intake and increased years after menopause. From a multiple regression analysis, the significant factors that can predict the MCI were years after menopause, sex, daily vegetable intake and hormonal replacement. The incidence rate of high risk of developing osteoporosis in females, no vegetable intake and no hormonal replacement subjects occurred 7.50, 2.22 and 2.63 times greater than in males, vegetable intake and hormonal replacement subjects, respectively. In postmenopausal women since 1-2, 3-5, 6-10, 11-15 and > 15 years, the incidence rate were 5.24, 14.51, 17.01, 20.86 and 29.76 times greater than the rate of premenopausal women. Concerning perimenopausal women, only 2 of all factors influenced the measured mBMD and MCI. The incidence rate of high risk of developing osteoporosis in women who intake protein > 30 g/d and intake medicine (corticosteroid) was 2.96 and 6.16 times greater than < 30 g/d protein intake and no medicine intake subjects.

Computed X-ray densitometry measurement of mBMD & MCI in normal Thai and osteoporotic patients.

To establish the reference values of age-related change of metacarpal bone mineral density (mBMD) and metacarpal index (MCI) in screening for osteoporosis, both postero-anterior (PA) hands and lateral thoraco-lumbar radiography were done on 1,182 normal volunteers aged 17-83. From PA hands radiographs, mBMD and MCI were measured by computed X-ray densitometry (CXD) (Bonalyzer, Teijin Ltd., Tokyo). Exclusion of the surgical menopause condition and the causes of affected bone loss, the results show that mean mBMD and MCI in various age groups were significantly different (p-value < 0.005 for both) in females. Both values increased gradually from age under 20 and peaked in the 30-39 years age group, then decreased gradually until age 50 and decreased markedly after age 50. The yearly rate of bone loss from the peak density detected by mBMD and MCI was 1.3 per cent and 1.6 per cent between aged 50-59, 1.6 per cent and 2.7 per cent in subjects aged 60-69, 1.3 per cent and 3.2 per cent in those aged 70-79. However, mBMD and MCI in males did not show a downward trend with age. It indicated that a screening program for early prevention of osteoporosis may be necessary only in females before, during and after menopause. Because 92.3 per cent of 39 osteoporotic subjects had abnormal CXD measurements lower than -2 standard deviations (SD) limit of mean mBMD in young healthy women (aged 20-40 years), this value appeared to constitute a satisfactory definition of "high risk of developing osteoporosis". The incidence rate of high risk of developing osteoporosis was 3.03 per cent in a normal young population, while the risk rate occurred 4.76, 13.14, 34.28, 47.30 and 47.00 per cent in subjects aged 40-49, 50-59, 60-69, 70-79 and > 80, respectively. Results confirmed the necessity of early prevention of osteoporosis in postmenopausal women. These measurements may be appropriate for mass screening to separate patients who have a greater risk for development of osteoporosis from those at lesser risk.