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Summary: There is a wide variation in fracture probabilities estimated by Asian FRAX models, although the outputs of South Asian models are concordant. Clinicians can choose either fixed or age-specific intervention thresholds when making treatment decisions in postmenopausal women. Cost-effectiveness of such approach, however, needs to be addressed., Purpose: This study examined suitable fracture probability intervention thresholds (ITs) for Sri Lanka, based on the Sri Lankan FRAX model., Methods: Fracture probabilities were estimated using all Asian FRAX models for a postmenopausal woman of BMI 25 kg/m² and has no clinical risk factors apart from a fragility fracture, and they were compared. Age-specific ITs were estimated based on the Sri Lankan FRAX model using the method followed by the National Osteoporosis Guideline Group in the UK. Using the age-specific ITs as the reference standard, suitable fixed ITs were also estimated., Results: Fracture probabilities estimated by different Asian FRAX models varied widely. Japanese and Taiwan models showed higher fracture probabilities while Chinese, Philippine, and Indonesian models gave lower fracture probabilities. Output of remaining FRAX models were generally similar. Age-specific ITs of major osteoporotic fracture probabilities (MOFP) based on the Sri Lankan FRAX model varied from 2.6 to 18% between 50 and 90 years. ITs of hip fracture probabilities (HFP) varied from 0.4 to 6.5% between 50 and 90 years. In finding fixed ITs, MOFP of 11% and HFP of 3.5% gave the lowest misclassification and highest agreement., Conclusion: Sri Lankan FRAX model behaves similar to other Asian FRAX models such as Indian, Singapore-Indian, Thai, and South Korean. Clinicians may use either the fixed or age-specific ITs in making therapeutic decisions in postmenopausal women. The economical aspects of such decisions, however, need to be considered.

The FRAX software developed by the World Health Organization provides a method to estimate fracture probability of old men and women based on their bone mineral density (BMD) and clinical risk factors (CRFs). The validity of 4 selected ethnic-specific FRAX tools in determining prevalent fracture or treatment decisions in a group of postmenopausal women from Sri Lanka was examined. Women with a history of fragility fracture/s and those who were detected to have femoral neck T-score<2.5 were considered eligible for specific osteoporosis treatment. Ten-year all osteoporotic fracture (vertebral and nonvertebral) probability (10y-AOFP) of 481 postmenopausal women were estimated on US Caucasian, US Asian, Japanese, and Chinese FRAX tools, first using CRFs alone and then combining with femoral neck T-scores. At 20% 10y-AOFP, Chinese tool showed a very low sensitivity in detecting prevalent fracture or detecting women needing intervention (1.3%). Sensitivities observed with US Asian and Japanese tools ranged from 33% to 42%, showing their limitations in predicting prevalent fracture in this group of women. The US Caucasian tool, either with CRFs alone or with BMD incorporated, showed a relatively higher sensitivity in detecting fractures or identifying those needing interventions (71% and 76%, respectively). Furthermore, the US Caucasian tool showed a relatively high specificity (ranging from 70% to 87%). In conclusion, this analysis showed the limitations of the current FRAX tools in predicting fractures when applied to a different ethnic group. Until a separate FRAX tool is developed, the US Caucasian tool can be used to predict fractures in Sri Lankan postmenopausal women., (Copyright (c) 2010 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.)

There is paucity of studies related to parity and bone mineral density in South Asian countries. We recruited 713 healthy, community dwelling post-menopausal women from seven provinces in Sri Lanka for this survey. The number of pregnancies, including miscarriages beyond 20 weeks of gestation, was recorded. Women with diseases and those who have taken drugs that can affect bone mineral density (BMD) were excluded (n = 15). Phalangeal BMD and bone mineral content (BMC) were measured using AccuDEXA in 713 women. Mean (SE) BMD of nulliparous women (n = 32), women with one to two pregnancies (n = 284), three to four pregnancies (n = 290) and more than four pregnancies (n = 107) were 0.437(0.014), 0.454(0.005), 0.455(0.005) and 0.417(0.006) g/cm(2), respectively (P < 0.001). Corresponding mean (SE) BMCs were 1.30(0.063), 1.41(0.021), 1.43(0.022) and 1.32(0.033) g, respectively (P < 0.001). Women with more than four pregnancies were older and lighter when compared with other groups. When results were adjusted for current age and current weight, differences in mean BMD and BMC between groups became non-significant. BMD of nulliparous women remained low in all analyses. We report a significant difference in unadjusted phalangeal BMD in women categorized according to their parity. Women with one to four pregnancies had the highest phalangeal BMD and BMC, while multi-parous (more than four pregnancies) and nulliparous women had lower values. However, in an adjusted analysis, the differences in BMD and BMC were partially explained by the differences of age and body weight between the groups and the unique effect of parity was difficult to determine. Women with lower BMD may have a higher risk of future fractures.

To establish normative reference values and to study the age-related trends in phalangeal bone mineral density (BMD), 4504 male and 5215 female volunteers aged 20 yr or more were recruited from 7 provinces from October 2004 to October 2005. Subjects suffering from diseases and those who were taking medications, which could affect BMD were excluded from the analysis (n=530). Phalangeal BMD was measured in the nondominant hand using an AccuDXA. Men and women were categorized to age groups of 20-29 (1087 men and 1079 women), 30-39 (1122 men and 1146 women), 40-49 (1148 men and 1455 women), 50-59 (810 men and 1111 women), 60-69 (250 men and 335 women), and 70 yr or more (87 men and 94 women). Mean BMDs (SD) of men in above categories were 0.595 (0.057), 0.603 (0.061), 0.591 (0.066), 0.576 (0.069), 0.558 (0.077), and 0.522 (0.079) g/cm2, respectively. The corresponding BMDs (SD) in women were 0.495 (0.057), 0.506 (0.062), 0.502 (0.064), 0.462 (0.072), 0.406 (0.072), and 0.340 (0.055) g/cm2, respectively. Peak BMD was seen in 30-39-age category in both sexes. Women after 50 yr lost BMD at a rate of 0.006 (standard error 0.0003) g/cm2/yr, whereas the corresponding value in men was 0.002 (standard error 0.0001) g/cm2/yr. These data provide normative reference data for the calculation of T-score and Z-score for phalangeal BMD in Sri Lankan men and women aged more than 20 yr.

Associations between lean mass, fat mass, and bone mass have been reported earlier; however, most of those studies have been done in Caucasian populations, and data from Asian countries, especially those in South Asia, are limited. We examined the associations between lean mass, fat mass, bone mineral density (BMD), and bone mineral content (BMC), determined by dual-energy X-ray absorptiometry technology, in a group of healthy, middle-aged, premenopausal female volunteers. The mean (SD) age of the women (n = 106) was 42.1 (6.1) years and the mean (SD) body mass index was 24.3 (3.6) kg/m(2). Total body BMD, total body BMC, and BMD in total spine, total hip, and femoral neck showed statistically significant partial correlations (adjusted for age) with total fat mass (r = 0.19-0.43, P < 0.05) and lean body mass (r = 0.28-0.54, P < 0.05). Truncal fat mass correlated positively with total body BMC and BMD at total hip and femoral neck (r = 0.33-0.40, P < 0.001). When a stepwise regression model was fitted, lean mass remained the strongest predictor of total body BMD, total body BMC, and total spine BMD (regression coefficients = 0.004-0.008 g/cm(2) per 1-kg change in lean mass, P < 0.001). Similarly, crude BMD and BMC increased across the tertiles of lean mass (P trend < 0.05). We show that lean mass is the strongest predictor of total body BMC and BMD at different sites, although positive correlations with fat mass also exist.

Indices of hip geometry are known to be predictive of hip fractures while sex and ethnic differences in hip geometry have been previously demonstrated. Age-related trends in hip geometry among Asians, however, have not been studied sufficiently. A total of 280 healthy, perimenopausal women, aged between 32 and 97 years, were selected from the Community Study Area of the Faculty of Medicine, Galle, Sri Lanka. Hip DXA images were analyzed further to calculate the hip axis length, neck-shaft angle, and femoral neck width at the narrowest point of the femoral neck. Standard formulae were used to calculate cross-sectional area, cross-sectional moment of inertia, and section modulus in the femoral neck region. Mean (SD) age, weight, height, femoral neck bone mineral density (BMD), hip axis length, neck-shaft angle, neck width, cross-sectional area, and cross-sectional moment of inertia of the study sample were 56.8 (13.0) years, 47.8 (10.1) kg, 1.48 (0.06) m, 0.704 (0.147) g/cm(2), 90.6 (5.6) mm, 123.2 (5.7) degrees, 2.99 (0.24) cm, 2.00 (0.42) cm(2), and 1.62 (0.47) cm(4), respectively. Height and weight of subjects had positive correlations with most of the indices of hip geometry. Femoral neck BMD, cross-sectional area and section modulus showed a rapid reduction during the postmenopausal period. With advancing age, there was a marginal but statistically nonsignificant expansion of the neck width, increase in the hip axis length, and narrowing of the neck-shaft angle. In conclusion, this study demonstrated a gradual loss of BMD in postmenopausal age, accompanied by thinning of the cortical shell and deterioration of the resistance to bending in the femoral neck of this group of healthy women. The clinical relevance of the marginal changes seen in other indices such as neck-shaft angle, hip axis length, and neck width is not known.