The association of dietary calcium, bone mineral density and biochemical bone turnover markers in rural Thai women.

OBJECTIVE: To investigate the relative contribution of dietary calcium intake on bone mineral density (BMD) and biochemical bone turnover markers in rural Thai women. MATERIAL AND METHOD: A cross-sectional investigation was designed in 255 rural Thai women. Usual dietary calcium intake was determined by 3-day food records and quantitative food-frequency questionnaire. BMD was measured by DXA. The three markers for bone turnover event: serum total alkaline phosphatase, serum N-mid osteocalcin and type I collagen C-telopeptide, including serum calcium and were determined in 125 women in the present study. RESULTS: An average daily calcium intake in the present study was 265 mg/day. Two hundred and thirty three out of 255 women (87%) consumed dietary calcium less than half of the recommended value and only 3% of women (n = 7) had calcium intake > 800 mg/day. After controlling certain parameters: age and body mass index, women who consumed higher amount of dietary calcium had significantly higher BMD at all sites. Moreover highly increased bone turnover markers were observed in those with lowest quartile calcium intake. Women with osteopenia and osteoporosis were older, lower BMI, consumed less calcium and had significantly higher values of all biochemical bone turnover markers than those who had normal BMD. CONCLUSION: The present study showed that a habitual diet of the rural Thai population might not provide enough calcium as needed for bone retention and for prevention of bone loss in the following years. Modification of eating pattern by promotion of increased consumption of locally available calcium rich food may be beneficial for prevention of osteoporosis among this population.

Dietary calcium intake among rural Thais in Northeastern Thailand.

OBJECTIVES: The present study examined the amount and relative contribution of calcium from the habitual diet among rural Thais. MATERIAL AND METHOD: Calcium intake was assessed using 3-day food records and interviewer-administered quantitative food-frequency questionnaire, containing 73 food items. RESULTS: The authors recruited 436 healthy participants (181 men and 255 women), between 20 and 85 years of age. Averaged daily calcium intake among men and women were 378.6 and 265.6 mg, respectively. Sixty-seven percent of men and eighty seven percent of women had less dietary calcium intake than half of the recommended level (< 400 mg/day) whereas only 6 and 3% had an intake more than 800 mg/day. The major food sources of dietary calcium was glutinous rice (32 percent) followed by small animals with edible bones (31 percent) and fresh and fermented fish (20 percent). Dairy products and vegetables constituted only 8 and 5% of dietary calcium, respectively. CONCLUSION: The habitual diet among rural Northeast Thais does not meet the recommended calcium intake level. To promote more consumption of dairy products and locally-available calcium-rich foods would be beneficial to prevent osteoporosis among this population.

Association between waist circumference and percentage body fat among rural Thais.

OBJECTIVE: Determine the association between waist circumference (WC) and percentage body fat (%BF) and to develop cut-off values and evaluate the accuracy of WC in the definition of obesity in rural Thai population. MATERIAL AND METHOD: A cross-sectional, epidemiologic study in 181 men and 255 women aged 50+/-16 yr (mean+/-SD; range: 20-84 yr) sampled by stratified clustering sampling method, was designed. Percentage body fat was measured by dual energy X-ray absorptiometry (GE Lunar Corp, Madison, WI). The "golden standard"for defining obesity was%BF > or = 25 in men and%BF > or = 35 in women. Waist circumference in centimeter was measured. RESULTS: In this study, the %BF-based prevalence of obesity in men and women was 8.3% and 44%, respectively. However using the WC cut-off (WHO) of 102 cm in men and 88 cm in women, only 1.7% of men and 24% of women were classified as obese. WC was a significant predictor of %BF, such that in men, a WC of 93 cm would predict a %BF of25%, and in women a WC of 84 cm would correspond to a %BF of 35%. The area under the receiver operating characteristic curve was 0. 87 and 0. 88 in men and women, respectively. In conclusion, waist circumference is a reasonably useful indicator of obesity. CONCLUSION: The cut-off values of WC for diagnosing obesity should be lower in Thailand than in Western countries.

Relationship of body composition and circulatory adiponectin to bone mineral density in young premenopausal women.

OBJECTIVE: Adiponectin is a recently discovered hormone secreted by adipocytes. Adiponectin plays an important role in the regulation of insulin sensitivity as well as the propensity to inflammation and atherosclerosis. In the present study, the authors explore the relationship between adiponectin and bone mass in premenopausal women. The relationship of fat mass compared to lean body mass to bone mass was also investigated MATERIAL AND METHOD: Two hundred premenopausal women aged between 20 and 40 years were studied. Bone mineral density (BMD) was measured at L2-4 and femoral neck by dual-energy X-ray absorptiometry (DEXA). Serum adiponectin concentrations were measured by radioimmunoassay. RESULTS: At the lumbar spines, factors associated with BMD were age (p < 0.01) and lean body mass (p < 0.001). No independent association with fat mass was demonstrated Likewise, at the femoral neck, only lean body mass was related to BMD (p < 0. 01). In terms of the relation of serum adiponectin to BMD, no association of serum adiponectin to BMD at the lumbar spines or femoral neck was found CONCLUSION: Altogether, the present findings do not suggest the independent role of adiponectin in the accrual of bone mass in females, although such a role still cannot be excluded in men or postmenopausal women.

Prevalence of osteoporosis in Thai men.

BACKGROUND: Osteoporosis is a growing health problem not only in women but also in men. However, there is a scarcity of epidemiologic data to study osteoporosis in Thai men. OBJECTIVES: To examine the bone mineral density (BMD) and to determine the prevalence of osteoporosis in Thai men. MATERIAL AND METHOD: A total of 412 men (159 from Bangkok and 253 from Khon Kaen, respectively) averaging 51 +/- 16 years of age, were measured for BMD at the femoral neck and lumbar spine by dual energy X-ray absorptiometry (LUNAR Corporation, WI, USA). RESULTS: The peak BMD was observed in men 20-29 years of age at both the femoral neck (mean +/- SD, 1.10 +/- 0.15 g/cm2) and lumbar spine (mean +/- SD, 1.17 +/- 0.13 g/cm2). The prevalence of osteoporosis in the entire group of subjects was 12.6, 4.6 and 3.9 per cent at the femoral neck, lumbar spine and both sites, respectively. The prevalence of osteoporosis increased with advancing age and was significantly higher at the femoral neck in urban men than rural men (18.2 vs 9.2 per cent, p < 0.05) but comparable at the lumbar spine (5.0 vs 4.3 per cent, p = 0.81). The correlation between femoral neck and lumbar spine BMDs was 0.53 (p < 0.001). In univariate analysis, increased age, lower weight and lesser height were each associated with lower femoral neck BMD, whereas only lower weight and lesser height were associated with lower lumbar spine BMD. However, when the three factors were entered simultaneously, only increased age and lower weight were significantly associated with lower femoral neck BMD and only lower weight had a significant association with lower lumbar spine BMD. CONCLUSION: The present study demonstrated descriptive BMD data, normal BMD reference values for diagnosis and reported the prevalence of osteoporosis in Thai men.

Estimated volumetric bone mineral density in a rural Thai men and women: Khon Kaen Osteoporosis Study (KKOS).

The authors examined the areal bone mineral density (aFNBMD) and estimated volumetric bone mineral density at the femoral neck (vFNBMD) in rural Thai men and women. A total of 181 men and 255 women, between 20 and 84 years of age, living in rural areas of Khon Kaen province, were randomly selected. Areal FNBMD and estimated v FNBMD were determined using dual energy X-ray absorptiometry (DPX-IQ, GE Lunar Corp, Madison, WI). Men had a significantly higher aFNBMD than women, whereas the estimated vFNBMD was similar regardless of sex. The peak for the aFNBMD vs. vFNBMD was observed between 20 and 29 vs. 30 and 39 years of age in men and women, respectively. The prevalence of osteoporosis in men and women using estimated vFNBMD vs. aFNBMD cut-offs was 19 and 14.2 vs 11.8 and 26 percent, respectively. Prevalence increased with age. Estimated vFNBMD shows only small sex-correlated differences in bone density. Estimated vFNBMD was more sensitive than aFNBMD, when used to define the osteoporotic cut-offs in men, while it was less sensitive than aFNBMD in women.

Association of circulating leptin with bone mineral density in males and females.

Leptin, a hormone produced by fat cells, possesses several physiological functions not limited to energy balance. Recently, leptin has been shown to inhibit bone formation through its action at the hypothalamus. In the present study, the authors explored the association of leptin with bone mineral density (BMD) in men and women according to menopausal status. Subjects consisted of 75 men, 51 premenopausal women and 63 postmenopausal women aged 20-80 years. All were healthy and did not take medication which may affect bone metabolism. BMD was measured at L2-4 and femoral neck by DEXA. Serum leptin concentrations were measured by radioimmunoassay. Serum leptin in males was independently related to BMD at L2-4 (r = -0.36, p < 0.05) and the femoral neck (r = -0.32, p < 0.05) in a multiple linear regression model with age, body mass index (BMI), serum free testosterone, estradiol and leptin as independent variables. In premenopausal women, serum leptin correlated negatively to L2-4 (r = -0.29, p < 0.01) and femoral neck BMD (r = -0.29, p < 0.05) independently of age and BMI. However, in postmenopausal women, no association of leptin with BMD was found after controlling for age and BMI. The authors concluded that circulating leptin is negatively associated with BMD in men and premenopausal women, but not in postmenopausal women. The negative associations found in both premenopausal women and men in the present study strengthen the notion that leptin may inhibit bone formation during the accumulation of bone mass early in life

Earlier onset of pubertal maturation in Thai girls.

BACKGROUND: Recent studies in the USA and Hong Kong demonstrated the onset of puberty in girls has shifted toward a younger age. Based upon previous studies on variations of pubertal maturation in Thai girls, the secular trend has also moved toward an earlier age. The latest study in 1995 revealed the mean age of menarche was 12.3 years. OBJECTIVES: To identify the onset of puberty, menarche and pubarche in female children and adolescents in 2 Bangkok schools. METHOD: Three hundred school girls aged 9-19 years were enrolled in the study. Data were collected from January 1997 through December 1999. Assessment of pubertal staging by Tanner's criteria was performed by a trained pediatrician. All were in good physical health and had normal height and weight. The median ages of thelarche, menarche and pubarche were estimated by probit analysis. All other parameters were expressed as mean +/- SD. RESULTS: The median ages of thelarche and pubarche were 9.4 and 11.1 years, respectively. Two hundred and twenty one girls had experienced menstruation. The median age of menarche was 11.2 years, whereas, the mean age was 12.1 years. Most girls reached near final adult height after 14 years old. CONCLUSION: The secular trend in decline of the ages of thelarche (or puberty) and menarche was observed in Bangkok girls. Further study in a larger population including a younger age group is required to define the current reference interval of onset of puberty.

Influence of normal ageing on mechanism of bone loss in women and men in Bangkok.

Age and sex related changes in bone metabolism are of interest in the pathogenesis of osteoporosis. However, most data in the literature were studied in Western countries. In a tropical country, such as Thailand, little is known of vitamin D status and bone remodeling. Thus, the aim of this study was to determine the changes of vitamin D levels and biochemical markers of bone turnover in healthy women and men of various age groups between 20-80 years who were living in Bangkok. From the results, vitamin D levels of various age groups did not alter significantly between men and women except in the sixth decade of women. However, men had higher levels of vitamin D than women. In women, all biochemical markers of bone turnover increased with age, with a sharp increase at the onset of menopause. In contrast, biochemical markers of bone turnover in men gradually declined with advancing age. CONCLUSION: There was no evidence of vitamin D deficiency in the Bangkok population. Women and men showed different age-related changes in bone metabolism.

Difference in goiter rates between two areas in Mae Hong Son Province despite an equally sufficient iodine supply.

The study was designed to investigate the problem of endemic goiter and iodine supplementation in Mae Hong Son, Thailand. Routine school data still showed high goiter rates in many areas. Six such schools and five schools with declining prevalence of goiter were selected. A single examiner examined all the children. Their weight, height, body mass index, ethnicity, history of iodine intake and migration were recorded. Urine samples were collected for measuring iodine and thiocyanate levels. From 653 children, 105 and 13 were found to have grade 1 and 2 goiter status, respectively. Median values of urine iodine level in children from all schools suggested sufficient iodine supplementation. Multivariate analysis showed that hilltribe minorities had a 2.09 times higher risk of endemic goiter than Thai children. Urine thiocyanate levels among children from high prevalence schools were significantly higher than those from low prevalence schools. No other significant correlation was found. Possible roles of other known and unknown goitrogens should also be investigated.

Incidence of hip fracture in Chiang Mai.

The reported incidence of hip fracture varies to a large extent across regions. Most studies relied on hospital data under the assumption that nearly all cases of hip fracture get access to hospital care. As in many developing countries, a number of hip fracture cases in Thailand might not seek care in hospitals due to geographical, socio-cultural and financial barriers. Therefore, using hospital data alone, could lead to under estimation of the magnitude of hip fracture. This study was undertaken to obtain such information using a combined method of hospital discharge survey and a cross sectional community survey. It resulted in an estimated incidence of 151.2 per 100,000 (95% CI 136.7-167.2) from the hospital survey and 185.2 per 100,000 (95% CI 138.1-247.6) from the community survey. In comparison to developed countries, age-adjusted incidence of hip fracture in this study was markedly lower than that reported from developed countries. It was argued that different degree of urbanization might explain the discrepancy. This implicated promotion of physical activity as a public health measure to prevent hip fracture.

Bone mineral density in rural Thai adults living in Khon Kaen province.

OBJECTIVES: To define the bone status and pattern of bone loss in a normal adult population living in a rural area of Khon Kaen province. STUDY DESIGN: A descriptive study. SETTINGS: Department of Medicine, Faculty of Medicine, Khon Kaen University, Thailand. Subjects 436 subjects (181 men and 255 women), aged 20-80 years. MAIN OUTCOME MEASURES: Bone parameter including total bone mineral density (BMD), the bone mineral density at different sites such as forearm, lumbar spine and hip, bone mineral content (BMC) were measured by dual energy X-ray absorptiometry (DEXA). RESULTS: The result revealed that women had lower bone mass at various bone sites than men. The peak bone mass in women was observed between 30-39 years of age except at the distal radius which occurred between 20-29 years of age while the peak bone mass in men was observed between 20-29 years of age. It was also shown that bone loss occurred in both men and women with advancing age. The rate of decline at all sites in women was greater than men especially when they were over 60 years old. When comparisons were made between pre and post-menopausal women, the mean of bone mineral density in pre-menopausal women was 1.18 +/- 0.08, 0.69 +/- 0.06, 0.69 +/- 0.06, 1.0 +/- 0.13, 1.15 +/- 0.13 g/cm2 at total body, mid-shaft radius, ultra distal radius, femoral neck and lumbar spine, respectively while the mean of bone mineral density in post-menopausal women was 1.02 +/- 0.12, 0.54 +/- 0.11, 0.54 +/- 0.11, 0.75 +/- 0.16, 0.88 +/- 0.2 g/cm2 at total body, mid-shaft radius, ultra distal radius, femoral neck and lumbar spine, respectively which were lower than BMD in pre-menopausal women (p<0.05). The mean bone mineral content (BMC) in pre-menopausal women was 2401+318.3 g while in post-menopausal women it was 1915.4+421.7 g (p<0.05). The rate of bone loss correlated with the duration after menopause. In this study, using World Health Organization criteria for diagnosis of osteopenia and osteoporosis and a reference value obtained from Khon Kaen young adults, the prevalence of osteopenia in Khon Kaen women subjects was 37.4 per cent at femoral neck, 30.2 per cent at lumbar spine, 44.5 per cent at ultra distal radius, 31.5 per cent at mid-shaft radius and the prevalence of was osteoporosis 19.3 per cent at femoral neck, 24.7 per cent at lumbar spine, 18.5 per cent at ultra distal radius and 26.4 per cent at mid-shaft radius. CONCLUSION: The result of this study demonstrated the bone parameters in rural Thai adults living in Khon Kaen province, the pattern of bone loss, the difference between men and women and finally the prevalence of osteopenia and osteoporosis.