Clinical inertia in thyrotropin suppressive therapy for low-risk differentiated thyroid cancer: A real-world experience at an endocrine center in Bangkok

The management of low-risk differentiated thyroid cancer (DTC) has evolved over time toward treatment de-escalation. However, overtreatment with supraphysiological dose of levothyroxine (LT4) continues to be observed despite current clinical guideline. This study aimed to assess the actual thyrotropin suppressive therapy for low-risk DTC patients at an endocrine center in Bangkok. This retrospective study included patients with low-risk DTC who were regularly follow-up for at least 18 months at Theptarin Hospital between 2016 and 2022. The serum thyroid stimulating hormone (TSH) levels were stratified as TSH < 0.1 mIU/L; TSH 0.1 to 0.5 mIU/L; TSH 0.5 to 2.0 mIU/L; and TSH > 2.0 mIU/L. The initial risk stratification (IRS) and dynamic risk stratification were determined at 12 months of follow-up after completing the initial treatment and at the last visit. The clinical factors associated with overtreatment with LT4 were analyzed. A total of 102 patients (83.3% female, age at diagnosis 41.8 ± 13.6 years, mean tumor size 1.6 ± 1.0 cm) were evaluated with a mean follow-up of 5.9 years. The IRS classified 92.2% of patients after the initial treatment and 93.1% of patients at the last follow-up visit into the excellent response category. The mean LT4 daily dosage at the last follow-up was 121.3 ± 44.8 µg/day. Serum TSH levels were in an appropriate target range according to IRS in only 8.8% (9/102) of the patients and then improved to 19.6% (20/102) at the last follow-up visit. Further analysis showed that treating physicians with ≥10 years of practice was associated with severe TSH suppression therapy (TSH < 0.1 mIU/L). Despite the current clinical guideline recommendations and scientific evidences, less than one-fifth of low-risk DTC patients achieved the appropriate serum TSH target. While the proportion of an optimum LT4 suppressive had improved during the study period, further efforts are needed to overcome this clinical inertia.

Recurrence Factors and Characteristic Trends of Papillary Thyroid Cancer Over Three Decades

Background: The prevalence of thyroid cancer is rising worldwide. Although thyroid cancer has a favorable prognosis, up to 20% of patients experienced recurrent disease at some point during follow-up. The present study aimed to examine the recurrent factors that determined the outcomes of papillary thyroid cancer (PTC) and the characteristic trends in Thai patients over the last 30 years in a single institute. Methods: We reviewed the clinical data of all patients with PTC who were treated between 1987 and 2019. Clinical characteristics, epidemic trends, factors associated with the persistent or recurrent disease, disease-specific survival rate and disease-free survival rate were analysed. Results: A total of 235 patients with PTC who were registered between 1987 and 2019 were reviewed. The mean age was 41.0 ± 14.3 years, with a mean follow-up of 113 months. Papillary thyroid microcarcinoma (PTMC) was consistently increased and accounted for 21.4% (50/235) of total cases. According to American Thyroid Association (ATA) risk stratification, high ATA risk was found 24% of all PTMCs in the last decade, and 16.7% of these patients experienced local recurrence during the follow-up period. Coexistence with Hashimoto’s thyroiditis (HT) was found in one-fifth of the patients with PTC and was correlated with a low recurrent rate (HR 0.21, p = 0.009). Factors associated with the persistent or recurrent of disease included age &gt; 55 years and high ATA risk. The overall disease-free survival rate and disease-specific survival rate were 77.4% and 98.3%, respectively. Conclusions: The prognosis of PTC is generally considered favorable. However, more than one-third of patients with PTMC demonstrated more aggressive clinical behavior, particularly in the last decade of the study. Coexistence with HT might contribute to a better prognosis in cases of PTC.

Practice patterns and outcomes in the management of Thai patients with Graves' disease

BACKGROUND

The treatment of hyperthyroid Graves' disease (GD) varies considerably among geographic areas. In this study, we aimed to evaluate practice patterns and treatment outcomes in Thai patients with hyperthyroid GD.

METHODS

A retrospective cohort study over 35 years (1985-2019) in patients with hyperthyroid GD was conducted. The trends of treatment options were compared periodically during the study period and the overall remission rate from each option was determined.

RESULTS

A total of 2736 hyperthyroid GD patients were treated and followed-up for at least 3 months over the study period (female 82.0%, mean age at diagnosis 36.3 ± 12.0 years, median duration of follow-up 74.5 months). Anti-thyroid drug (ATD) was the most commonly used treatment (78.0%), followed by RAI (21.0%), and surgery (1.0%). There was a significant downward trend for surgery, from 12.3% in the 1980s to only 0.2% in last phase of the study period. The preference for RAI therapy has also decreased in the last 5 years. Among ATD-treated patients, the remission rate was achieved only in 30.7 and 16.0% of all ATD-treated patients were eventually treated with RAI. Spontaneous hypothyroidism developed in 2.7% of the ATD-treated patients during a follow-up period. Almost all RAI-treated patients (97.1%) developed hypothyroidism.

CONCLUSIONS

Our present study highlighted the changing landscape of primary treatments for hyperthyroid GD toward ATD and the sharp downward trend in the surgical option. Even though ATD was associated with a low remission rate, it was preferred by many patients and physicians. The use of RAI as the primary treatment decreased in the last decade. However, RAI was a very effective treatment for Graves' hyperthyroidism but will inevitably induce hypothyroidism and a requirement for life-long replacement therapy.

Serum T3 Level and Duration of Minimum Maintenance Dose Therapy Predict Relapse n Methimazole-Treated Graves Disease

Background

Methimazole (MMI) has been advocated as a preferred option for most Graves disease (GD) patients. However, long-term remission after a course of MMI treatment is achieved in only 20% to 40% of patients, depending on the duration of follow-up.

Objective

To evaluate clinical factors for predicting relapse of GD in Thai patients after MMI treatment.

Methods

A retrospective analysis was performed of newly diagnosed patients with GD who achieved remission of hyperthyroid GD after at least 12 months of MMI treatment. Long-term outcomes were assessed and predictive factors of early and late relapse were evaluated.

Results

A total of 443 patients with newly diagnosed GD who were treated with MMI for at least 12 months from 1985 to 2019, and were able to discontinue medication, were studied. The mean age at diagnosis was 37.0 ± 11.4 years and 81.7% were female. Of the 320 patients (72.2%) who achieved initial remission after MMI treatment for 23 months, 106 patients (33.1%) experienced late relapse during the mean follow-up duration of 9.7 years after MMI withdrawal. The remission rates decreased from 36.4% at the first year after stopping MMI to only 20.7% at 10 years. High initial serum triiodothyronine (T3) level and duration of minimum maintenance dose therapy (MMDT) of <6 months were associated with late disease relapse after remission.

Conclusion

The long-term remission rate of Graves hyperthyroidism was achieved in one-fifth of MMI-treated Thai patients. Predictive markers for late relapse included high initial serum T3 level and a duration of MMDT of <6 months.

Recurrence Factors and Characteristic Trends of Papillary Thyroid Cancer over Three Decades

BACKGROUND

The prevalence of thyroid cancer is rising worldwide. Although thyroid cancer has a favorable prognosis, up to 20% of patients experienced recurrent disease during the follow-up period. The present study aimed to examine the trend of incidence and factors associated with recurrence and outcomes of papillary thyroid cancer (PTC) in Thai patients over the last 30 years.

METHODS

We reviewed the clinical data of all patients with PTC who were treated between 1987 and 2019 at Theptarin Hospital. Clinical characteristics, epidemic trend, factors associated with the persistence/recurrence of the disease, overall disease-specific survival rate, and overall disease-free survival rate were analysed.

RESULTS

A total of 235 patients with PTC who were registered between 1987 and 2019 were reviewed. The mean age was 42.5 ± 14.3 years, with a mean follow-up of 9.5 years. Papillary thyroid microcarcinoma (PTMC) was consistently increased and accounted for 21.4% (50/235) of total cases. The American Thyroid Association (ATA) risk stratification was high in 24% of all PTMCs in the last decade, and 16.0% of these patients experienced local recurrence during the follow-up period. Coexistence with Hashimoto's thyroiditis (HT) was found in one-fifth of the patients with PTC and was correlated with a low recurrence rate (HR: 0.16, P=0.013). Only age ≥55 years associated with the persistence/recurrence of the disease. The overall disease-free survival and disease-specific survival rates were 77.4% and 98.3%, respectively.

CONCLUSIONS

The prognosis of PTC is generally considered favorable. However, approximately one-fourth of patients with PTMC demonstrated more aggressive clinical behavior, particularly in the last decade of the study. Coexistence of HT contributed to a better prognosis.

Impact of first-line treatment choice on long-term outcomes of hyperthyroid Graves' disease patients with thyrotoxic periodic paralysis

Background

Thyrotoxic periodic paralysis (TPP) is a unique manifestation of Graves’ disease. While it is uncommon in Asian, it is extremely rare in Caucasian patients (0.1–0.2%). Previous studies suggested that TPP indicate more severity of Graves’ disease and definitive treatments should be used to prevent relapses.

Aim

To describe clinical features and impact of first-line treatment on long-term outcomes of TPP patients.

Method

A retrospective cohort study over 35 years (1985–2019) of TPP from Graves’ disease patients was conducted. All cases were analyzed and their clinical courses were compared between those who received anti-thyroid drugs (ATD) versus radioactive iodine (RAI) as a primary treatment. None of them underwent surgery.

Results

A total of 2964 hyperthyroid Graves’ disease patients were treated and followed-up at least 3 months over the study period. TPP was identified in 63 cases (2.1%) of all patients. There were 60 males and only 3 females with age at presentation of 35.0 ± 8.2 years. TPP was the first presentation of hyperthyroid Graves’ disease in 82.5% of them. During the acute attack of TPP, all patients presented with bilateral lower limb flaccid weaknesses with median serum potassium of 2.1 mmol/L. No fatal TPP cases were found. RAI was selected as primary treatment in 27 patients (42.9%). Nearly all RAI-treated patients rendered hypothyroidism with the median RAI dose at 15 mCi. No patients who were in remission after RAI treatment developed recurrent attack of TPP. In the remaining 36 ATD-treated patients with mean follow-up time at 9.1 years, relapse was found in 10 patients (27.8%) after the drug discontinuation and 6 patients suffered recurrent TPP. Only 8 ATD-treated TPP patients (22.2%) went into remission.

Conclusions

TPP is a rare complication of hyperthyroid Graves’ disease. Definitive treatment with RAI or thyroidectomy should be employed to prevent relapse and further attacks of TPP.

The efficacy of calcium supplementation alone in elderly Thai women over a 2-year period: a randomized controlled trial

Supplementation with elemental calcium 500 mg/day alone for 2 years is able to decrease bone turnover and is effective in retarding bone loss at lumbar spine and slowing bone loss at femoral neck in elderly Thai women who had low dietary calcium intake.

INTRODUCTION

Most elderly Thais have a total dietary calcium intake of less than the recommended amount. The aim of the study was to investigate the effect of calcium supplementation on bone mineral density and biochemical indices of bone remodeling in Thai postmenopausal women.

METHODS

Four hundred and four healthy postmenopausal women 60 years old or older without osteoporosis were recruited and conducted in a randomized, double-blinded, placebo-controlled trial. They were randomly given elementary calcium 500 mg/day or placebo for 2 years. Dietary calcium intake was calculated from the nutrient compositional analysis of the 3-day food records. Serum 25 hydroxyvitamin D was measured by radioimmunoassay and bone turnover markers were determined by electrochemiluminescence immunoassay.

RESULTS

The age of the subjects was 65.8 ± 4.4 years. All baseline characteristics of the subjects in the calcium-supplemented group and the placebo group were not statistically different. At the end of the study, significant decreases in serum C-terminal telopeptide of type I collagen and serum total procollagen type I amino terminal propeptide in the calcium-supplemented group were observed, while there was no change in the placebo group. In addition, plasma parathyroid hormone decreased, although not significantly, only in the calcium-supplemented group. Percent changes from baseline of lumbar spine (L2-L4) bone mineral density increased 2.76% in the calcium-supplemented group and 0.87% in the placebo group, whereas the percent changes from baseline of femoral neck decreased 0.21% in the calcium-supplemented group and 0.90% in the placebo group.

CONCLUSIONS

Calcium supplementation is necessary for the decrease of bone turnover and prevention of bone loss in Thai elderly women.

Prevalence of sarcopenia and associated factors among Thai population

The purpose of this study was to determine the prevalence of sarcopenia using the skeletal muscle index (SMI) criteria in the Thai population. The secondary objective was to demonstrate factors influencing low SMI in this population. Femoral neck bone mass density (BMD) was measured by dual-energy X-ray absorptiometry (GE Lunar, Madison, WI, USA) in 435 urban and 397 rural subjects (334 men and 498 women) between 20 and 84 years of age. Body mass index (BMI) was calculated from weight and height. The respective prevalence of sarcopenia among men and women was 35.33 % (95 % CI, 29.91, 40.41) and 34.74 % (95 % CI, 30.56, 39.10). Factors associated with sarcopenia using multiple logistic regression analyses in both sexes were (a) living in the city, (b) higher BMI, and (c) older age. Living in an urban area was the strongest factor, with an odds ratio (OR) of 17.26 ± 7.12 (95 % CI, 7.68, 38.76) in men and 8.62 ± 2.74 (95 % CI, 4.62, 16.05) in women (p < 0.05). The prevalence rate ratio for persons living in urban compared to rural areas was 2.01 (95 % CI, 1.14, 3.53) in men and 1.69 (95 % CI, 1.31, 2.17) in women (p < 0.05). Sarcopenia, as based on SMI, occurs frequently in the Thai population and increases with age. The prevalence of sarcopenia is particularly high among pre-retirement women (50-59 years of age) whereas the number of men with sarcopenia gradually rises with age. An urban environment is the most predictive factor for sarcopenia, followed by high BMI and age. Given the aging population, early recognition of this condition can be beneficial for prevention of an epidemic of sarcopenia-related disability.

Prediction of Percentage Body Fat in Rural Thai Population Using Simple Anthropometric Measurements

OBJECTIVE

To develop and validate sex-specific equations for predicting percentage body fat (%BF) in rural Thai population, based on BMI and anthropometric measurements.

RESEARCH METHODS AND PROCEDURES

%BF (DXA; GE Lunar Corp., Madison, WI) was measured in 181 men and 255 women who were healthy and between 20 and 84 years old. Anthropometric measures such as weight (kilograms), height (centimeters), BMI (kilograms per meter squared), waist circumference (centimeters), hip circumference (centimeters), thickness at triceps skinfold (millimeters), biceps skinfold (millimeters), subscapular skinfold (millimeters), and suprailiac skinfold (millimeters) were also measured. The sample was randomly divided into a development group (98 men and 125 women) and a validation group (83 men and 130 women). Regression equations of %BF derived from the development group were then evaluated for accuracy in the validation group.

RESULTS

The equation for estimating %BF in men was: %BF(men) = 0.42 x subscapular skinfold + 0.62 x BMI - 0.28 x biceps skinfold + 0.17 x waist circumference - 18.47, and in women: %BF(women) = 0.42 x hip circumference + 0.17 x suprailiac skinfold + 0.46 x BMI - 23.75. The coefficient of determination (R2) for both equations was 0.68. Without anthropometric variables, the predictive equation using BMI, age, and sex was: %BF = 1.65 x BMI + 0.06 x age - 15.3 x sex - 10.67 (where sex = 1 for men and sex = 0 for women), with R2 = 0.83. When these equations were applied to the validation sample, the difference between measured and predicted %BF ranged between +/-9%, and the positive predictive values were above 0.9.

DISCUSSION

These results suggest that simple, noninvasive, and inexpensive anthropometric variables may provide an accurate estimate of %BF and could potentially aid the diagnosis of obesity in rural Thais.

Prevalence of vitamin D insufficiency and low bone mineral density in elderly Thai nursing home residents

Background

Numerous emerging data from research on osteoporosis among Asians found differences from Caucasians. Therefore, the aim of this study was to determine the prevalence of vitamin D insufficiency and osteoporosis in elderly participants from two nursing homes in Thailand, a country located near the equator.

Methods

The subjects of this cross-sectional study comprised 93 elderly Thai women who were living in institutional long-term nursing homes for the aged. Demographic data, daily food and calcium intake, physical activity, and sunlight exposure were measured. Lumbar spine and femoral neck bone mineral density (BMD) and biochemical levels including serum 25 hydroxyvitamin D [25(OH)D] and bone turnover markers were assessed. Vitamin D insufficiency was defined as 25(OH)D level < 70 nmol/l.

Results

The mean age of subjects was 75.2 ± 6.0 (SD) years. Dietary calcium intake was low (322 ± 158 mg/day) The mean 25(OH)D level was 64.3 ± 14.9 nmol/L and the prevalence of vitamin D insufficiency was 38.7% (95% CI: 28.8%, 49.4%). There was no correlation between serum 25(OH)D concentrations and age (r = −.11, p = 0.3). The mean BMD of lumbar spine and femoral neck were 0.92 ± 0.19 and 0.65 ± 0.10 g/cm², respectively. Nearly a half of the subjects had osteopenia (44.1%, 95% CI: 33.8%, 54.8%) and osteoporosis (47.3%, 95% CI: 36.9%, 57.9%). Circulating C-terminal telopeptide of type I collagen (CTx) level correlated significantly with both lumbar spine (r = −0.26, p = 0.01) and femoral neck BMD (r = −0.25, p = 0.02).

Conclusions

More than one-third of Thai elderly women residing in nursing homes had vitamin D insufficiency. Almost all nursing home residents had osteoporosis and/or osteopenia.

Asymptomatic Paget's bone disease in ethnic Thais: a series of four case reports and a review of the literature

Paget's bone disease is quite common in some parts of Europe and countries inhabited by European emigrants, but it is rare in Asia. There have been only 13 reported cases in Southeast Asia, including one reported case from Thailand. Half of the previously reported cases had bone symptoms and the other half were asymptomatic, but were incidentally discovered when patients were being investigated for other medical problems. Here are reported cases of four asymptomatic patients who presented elevation of serum alkaline phosphatase during routine annual medical checkups. All patients were of Chinese descent and all cases were proven by biopsy. Based on this experience, we are of the opinion that a substantial number of unrecognized cases of Paget's disease exist among ethnic Thais. We feel that they would be revealed if clinicians were alerted of its presence and if they included it as a possible diagnosis together with metastasis and osteoporosis when examining bone lesions or when results for elevated serum alkaline phosphatase are detected during routine checkups. We also anticipate that a higher prevalence of this disease may occur in future Thai generations due to the addition of offspring from Asian-European intermarriages to offspring of Chinese descent in the ethnic Thai population.

Malic enzyme gene polymorphism is associated with responsiveness in circulating parathyroid hormone after long-term calcium supplementation

OBJECTIVE

To identify genetic variations associated with parathyroid hormone (PTH) suppression after long-term calcium supplementation.

DESIGN AND PARTICIPANTS

For high throughput SNP screening, subjects consisted of 171 postmenopausal women without osteoporosis at the lumbar spine. A separate group of 19 premenpausal women were recruited for calcium absorption study. Postmenopausal women in the screening group were given 500 mg/day calcium supplementation.

SETTING

Bangkok, Thailand.

MEASUREMENTS

Parathyroid hormone (PTH) and bone mineral density (BMD) were measured at baseline and 2 years after calcium supplementation. High throughput single-nucleotide polymorphism (SNP) screening was performed by comparing estimated allele frequencies derived from hybridization signal intensities of pooled DNA samples on Affymetrix's 10K SNP genotyping microarrays based responsiveness in PTH after calcium supplementation. Genotyping of SNP rs1112482 in malic enzyme gene (ME1) gene, a SNP among those with highest odds ratio of being related to PTH suppression after calcium, was performed in all postmenopausal subjects in the screening group and premenopausal women in the calcium absorption study group in which fractional calcium absorption was assessed by stable isotope dilution. Data were expressed as mean +/- SEM.

RESULTS

PTH significantly decreased after 2 years of calcium supplementation (4.7 ± 1.9 vs. 4.4 ± 1.6 pmol/L, P < 0.01). There was a significant increase in lumbar spine BMD (1.03 ± 0.01 vs. 1.01 ± 0.01 g/cm2, P < 0.001) but not femoral neck BMD. In 108 subjects whose PTH levels decreased after calcium, the suppression of PTH was higher in those with at least one C allele in rs1112482 of ME1 gene (-26.3 ± 2.1 vs. -16.9 ± 1.4%, P < 0.001). Fractional calcium absorption also tends to the higher in subjects in the calcium absorption study group with at least one C allele (n = 6) compared to those without the C allele (n = 13) (58.0 ± 4.9 vs. 49.3 ± 2.8%, P = 0.054).

CONCLUSION

Cytosolic malic enzyme 1 gene polymorphism is associated with the degree of suppression of parathyroid hormone after long-term calcium supplementation. The effect is probably mediated through an increase in intestinal calcium absorption.

The relationship of fetuin-A and lactoferrin with bone mass in elderly women

SUMMARY

The relationships of fetuin-A and lactoferrin to bone-related phenotypes were investigated in elderly women. Fetuin-A was associated not only with bone mineral density (BMD) but also with bone resorption marker suggesting an influence of fetuin-A on osteoclasts.

INTRODUCTION

The aim of this study is to investigate the relationship of bone-related phenotypes in elderly women with circulating fetuin-A and lactoferrin.

METHODS

Eighty-two elderly women were studied. Serum fetuin-A, lactoferrin, C-terminal telopeptide of type I collagen (CTx), total procollagen type 1 amino-terminal propeptide, and plasma intact parathyroid hormone (PTH) were analyzed. BMD of the lumbar spine at L2-4 and at the femoral neck was measured.

RESULTS

Serum fetuin-A was significantly associated with L2-4 BMD (r = 0.23, P < 0.05). After controlling for age and body weight, the association remained statistically significant. There was a significant association between serum fetuin-A and serum CTx (r = -0.37, P < 0.001). The association between fetuin-A and L2-4 BMD no longer existed after controlling for serum CTx. There were positive associations of circulating lactoferrin with plasma PTH (r = 0.24, P < 0.05) and serum CTx (r = 0.26, P < 0.05). No association between serum lactoferrin and BMD at the lumbar spine or femoral neck was detected.

CONCLUSIONS

Circulating fetuin-A is related to bone mass and bone resorption markers in elderly women. Lactoferrin, in contrast, is associated only with bone resorption markers.

Discrepant influence of vitamin D status on parathyroid hormone and bone mass after two years of calcium supplementation

OBJECTIVE

To investigate the influence of vitamin D status on parathyroid hormone and bone mass after a 2-year supplementation of calcium alone.

PATIENTS AND METHODS

Randomized, double-blind, placebo-controlled clinical trial, in healthy postmenopausal women without osteoporosis: three hundred and thirty-six subjects aged 60-97 years were studied and randomized to receive elemental calcium 500 mg/day (n = 175) or placebo (n = 161) for 2 years.

MEASUREMENTS

Changes in parathyroid hormone (PTH) and bone mineral density (BMD) from baseline and vitamin D status. Values are presented as means +/- SD.

RESULTS

After 2 years, subjects with calcium supplementation had significant decrease in plasma PTH level (4.4 +/- 1.7 vs 4.7 +/- 1.9 pmol/l, P < 0.01), improved lumbar BMD (1.031 +/- 0.12 vs 1.004 +/- 0.12 g/cm(2), P < 0.001) and total hip BMD (0.890 +/- 0.10 vs 0.883 +/- 0.10 g/cm(2), P < 0.001) without change in femoral neck BMD. In the placebo group, PTH level significantly increased (4.8 +/- 1.6 vs 4.5 +/- 1.5 pmol/l, P < 0.001), lumbar BMD slightly increased (1.027 +/- 0.14 vs 1.018 +/- 0.14 g/cm(2), P < 0.001), total hip and femoral neck BMD decreased (0.876 +/- 0.11 vs 0.887 +/- 0.11 g/cm(2), P < 0.001 and 0.783 +/- 0.10 vs 0.798 +/- 0.10 g/cm(2), P < 0.001, respectively). When subjects were classified according to baseline 25-hydroxyvitamin D [25(OH)D] levels into those with 25(OH)D in the lower tertile (lowVitD) and those in the middle and upper tertiles combined (normVitD). The degree of PTH suppression after calcium supplementation was significantly higher in the normVitD compared to the lowVitD groups (-5.6 +/- 26.7%vs 1.3 +/- 27.2%, P < 0.05). No effect of vitamin D status on the change in lumbar BMD after calcium supplementation was demonstrated. Despite the higher suppression of PTH, there was a slight decrease in femoral neck BMD after calcium supplementation in the normVitD group while femoral neck BMD was more or less maintained in the lowVitD group (-0.6 +/- 3.2%vs 0.5 +/- 2.9%, P < 0.05).

CONCLUSION

Calcium supplementation appears to affect femoral bone mass less in Thai postmenopausal women with adequate vitamin D status, despite higher suppression of PTH.

Genetic variant in the aquaporin 9 gene is associated with bone mineral density in postmenopausal women

This study investigated whether single nucleotide polymorphisms (SNP) in the aquaporin 9 (AQP9) gene is associated with bone mineral density (BMD) in Thai postmenopausal women, after an initial genome-wide screening using high-throughput SNP genotyping in pooled DNA samples. Subjects consisted of 516 postmenopausal women aged 50 or more. High-throughput SNP screening was performed by comparing the estimated allele frequency derived from hybridization signal intensities of pooled DNA samples on the Affymetrix 500 K SNP genotyping chip set. The SNP was then genotyped for each subject individually. Data were expressed as mean ± SEM. Pooled DNA SNP screening revealed the allele frequency of an intronic A/T SNP rs2414539 in the AQP9 gene as being different between subjects with femoral neck BMD in tertiles 1 and 3. Individual genotyping in all subjects revealed that femoral neck BMD in subjects with TT, TA, and AA genotypes were 0.79 ± 0.06 (n = 3), 0.75 ± 0.01 (n = 98), and 0.71 ± 0.01 g/cm(2) (n = 415), respectively. The presence of the T allele in rs2414539 was associated with femoral neck BMD (r = 0.11, P < 0.05) but not with lumbar spine BMD. The relationship was still significant after controlling for body weight and age (P < 0.05). Genetic variation in the AQP9 gene is associated with femoral neck BMD in postmenopausal women, and may represent one of the susceptibility genes for phenotypes related to bone mass.

Vitamin D status and bone health in healthy Thai elderly women

OBJECTIVE

The prevalence of hypovitaminosis D varies in different countries. Therefore, the current study was designed to assess vitamin D status and bone health in elderly women in Thailand, which is situated near the equator.

METHODS

This cross-sectional study was performed in 446 healthy women aged 60-97 y.

RESULTS

Serum 25-hydroxyvitamin D (25(OH)D) was 67.6 ± 15.7 (mean ± SD) nmol/L. Daily calcium intake was 309.5 ± 147.2 mg/d. Serum 25(OH)D levels tended to decline with bone mineral density (BMD) status. Based on functional health-based reference values, plasma-intact parathyroid hormone began to rise below serum 25(OH)D level 70 nmol/L and increase significantly when serum 25(OH)D was ≤ 60 nmol/L. Thirty-two percent of elderly women had 25(OH)D insufficiency (≤ 60 nmol/L). There was no trend toward a decrease in the concentration of serum 25(OH)D with age (r = -0.078, P = 0.10) and no significant inverse relationship with plasma intact parathyroid hormone values (r = -0.079, P = 0.097). However, a positive relationship was observed between serum 25(OH)D level and femoral neck BMD (r = 0.156, P = 0.001) but not lumbar spine L(2)-L(4) BMD (r = 0.093, P = 0.050). In addition, BMD at the femoral neck but not lumbar spine of the vitamin D insufficiency group was significantly lower than that of the vitamin D sufficiency group.

CONCLUSION

The optimum level of serum 25(OH) value in Thai elderly women should be higher than 70 nmol/L. Vitamin D insufficiency is observed in one-third of elderly women in Bangkok.

Sexual maturation in Thai boys

BACKGROUND

A worldwide secular trend towards earlier onset of puberty in girls has been noted during recent years. However, the data on sexual maturation of boys are relatively scarce and normative data of sexual maturation in Thai boys are still lacking.

AIM

To determine the age of secondary sexual maturation in normal Thai boys.

METHODS

Three hundred healthy urban boys aged 9-18 years were recruited during January 1997 to December 1999. Genital and pubic hair maturity staging was determined using the method of Marshall and Tanner. Testicular size was assessed by Prader orchidometer. Probit analysis was used to analyze the onset of puberty (gonadarche) and pubarche.

RESULTS

Median (range) ages of the onset of puberty and pubarche were 10.8 (9.5-12) and 12.4 (10.9-13.9) years, respectively.

CONCLUSION

The age of onset of genital development in boys living in Bangkok seems to be slightly earlier than that of boys in other countries. However, the onset of pubic hair development is comparable.

A comparative study of risk factors of femoral neck and intertrochanteric fracture in Thai men

OBJECTIVE

The objective of this study was to compare the risk factors related to hip fracture between intertrochanteric fracture and femoral neck fracture in Thai men.

MATERIAL AND METHOD

The study was conducted in Bangkok and its vicinity from July 1997 to September 1998. The cases were recruited and matched with the controls by age and sex. Multilogit model was performed for finding the significant factors associated to each type of hip fracture.

RESULTS

There were 73 femoral neck fractures, 144 intertrochanteric fractures, and 177 controls. It was found that both types of hip fracture were associated with the physical activity and the cerebrovascular accident. However, the Chinese parent race was significantly related to the femoral neck only (adjusted odds ratio (OR) 2.59, 95% confidence interval (CI): 1.21, 5.54) whereas the walking disability was specifically associated with the intertrochanteric fracture (adjusted OR 3.23, 95% CI: 1.29, 8.08).

CONCLUSION

Types of hip fracture should be concerned for strategic prevention in men since they have significant difference of risk factors.

Different risk magnitudes of femoral neck and intertrochanteric fractures in Thai women

OBJECTIVE

To study the risk factors associated of femoral neck and intertrochanteric fractures in Thai women.

MATERIAL AND METHOD

A case,control study was conducted in Bangkok and its vicinity between 1997 and 1998 to compare factors related to each type of hip fracture in Thai women. Cases, aged > or =51 years old, were diagnosed as intertrochanteric or femoral neck fracture and were matched with controls by age and sex. Multinomial logistic regression was performed for significant associated factors.

RESULTS

Recent physical activity and steroid-containing traditional medicine were strongly associated with intertrochanteric fractures (adjusted odds ratio (OR) 0.17 (95% CI: 0.07, 0.42) and 6.50 (95% CI: 1.93, 21.82), respectively) when compared to femoral neck fractures. Cerebrovascular accident (CVA) was more related to femoral neck fractures when compared to intertrochanteric fractures (adjusted OR 8.63 (95% CI: 2.28, 32.66), and 4.79 (95% CI: 1.19, 19.29), respectively).

CONCLUSION

Intertrochanteric fracture could be minimized more by encouraging physical activities and avoidance of steroid use while the reduction of femoral neck fracture should be achieved more by CVA prevention.

Reduced attenuation of bone resorption after oral glucose in type 2 diabetes

OBJECTIVE

To investigate the effect of oral glucose on bone resorption and osteoprotegerin (OPG) in subjects with varying degrees of glucose tolerance.

DESIGN AND PATIENTS

In a cross-sectional study, 163 postmenopausal women aged 50-88 years without previous history of diabetes, impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) were recruited. All subjects underwent a 75-g oral glucose tolerance test (OGTT) and were then classified as having normal glucose tolerance (NGT), IFG, IGT or diabetes according to American Diabetes Association (ADA) criteria.

MEASUREMENTS

Plasma glucose, serum insulin, C-terminal telopeptide of type I collagen (CTX-I) and OPG were measured.

RESULTS

Fasting insulin levels increased progressively from subjects with NGT, IFG/IGT to diabetes. After adjusted for age and body mass index (BMI), there was no significant difference in fasting CTX-I and OPG levels across the various degrees of glucose tolerance. After oral glucose, there was a significant decrease in serum CTX-I and OPG (P < 0.001) except for serum OPG in diabetic subjects. In addition, the percentages of change from baseline for both serum CTX-I and OPG were significantly less in diabetic subjects when compared to those in NGT subjects (-40.9% and 0.6% for diabetes and -50.2% and -10.6% for NGT, respectively).

CONCLUSIONS

Oral glucose intake causes suppression of serum CTX-I and OPG in postmenopausal women. The effect is attenuated in women with type 2 diabetes.

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.

The relationship of an Asian-specific screening tool for osteoporosis to vertebral deformity and osteoporosis

An Asian-specific screening tool for osteoporosis, the so-called OSTA index, was devised and is likely to be helpful in determining which postmenopausal women need bone mineral density (BMD) measurement. Besides BMD, prevalent vertebral fracture is a strong risk factor for future fractures. However, the relationship of the OSTA index to prevalent vertebral fractures is currently unknown. In this study, we evaluated the performance of the OSTA index in elderly Thai women and assessed the relationship of the index to prevalent vertebral deformities. Subjects consisted of 741 healthy Thai elderly women. BMD was measured by DEXA and T-score <or=2.5 SD is defined as osteoporosis. Prevalent vertebral deformities were determined by morphometric X-ray absorptiometry. OSTA index >-1 is classified as having low risk of osteoporosis, -1 to -4 as intermediate risk and, <-4 as high risk. Data were expressed as mean +/- SD. The mean age and body weight of subjects were 67 +/- 4.8 years and 57.8 +/- 8.7 kg, respectively. The area under the ROC curve for OSTA index to identify osteoporosis at femoral neck and lumbar spine was 0.80 and 0.72, respectively. Femoral neck osteoporosis was found in 40.4%, 6.3%, and 2.4% of subjects with high-risk, intermediate-risk, and low-risk OSTA indexes, respectively. With regard to vertebral deformities, the area under the ROC curve relating OSTA index to vertebral deformities was 0.70 (P < 0.001). The prevalence of vertebral deformities in according to the OSTA index was 19.2% in the high-risk, 7.9% in the intermediate-risk, and 2.8% in the low-risk group. We concluded that the OSTA index can be of assistance in the selection of postmenopausal women for BMD measurement. In addition, this index may be helpful in the identification of postmenopausal women with vertebral deformity and those who need antifracture treatments.

Chronic metabolic acidosis alters osteoblast differentiation from human mesenchymal stem cells

Bone histology of distal renal tubular acidosis patients showed decreased bone formation with impaired bone matrix mineralization that is not entirely explained by an alteration in the mineral balance. Data from in vitro studies suggests a direct inhibitory effect of metabolic acidosis on osteoblast function. We investigated the effects of chronic metabolic acidosis on osteoblast differentiation from mesenchymal stem cells (MSCs). Human MSCs were allowed to differentiate into osteoblasts in culture. Concentrated hydrochloric acid was added to the medium to lower the bicarbonate concentration and pH. The expression of various osteoblastic genes and proteins and bone matrix mineralization were examined. Chronic metabolic acidosis enhanced the messenger RNA (mRNA) and protein expression of early osteoblast transcription factor, runx-2, whereas inhibiting osterix and having no effect on ATF-4. The expression of type I collagen, the most abundant bone matrix protein, was increased following the same pattern of runx-2. Likewise, metabolic acidosis slightly enhanced the expression of mature osteoblastic gene, osteocalcin. Study on mineralization revealed suppressed alkaline phosphatase mRNA and enzyme activity. Despite the augmented collagen deposit in acidic culture, bone matrix mineralization was impaired. In conclusion, chronic metabolic acidosis alters osteoblast differentiation from MSCs through its diverse effect on osteoblastic genes and proteins resulting in an impairment of bone formation.

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.

A risk score for predicting incident diabetes in the Thai population

OBJECTIVE

The objective of this study was to develop and evaluate a risk score to predict people at high risk of diabetes in Thailand.

RESEARCH DESIGN AND METHODS

A Thai cohort of 2,677 individuals, aged 35-55 years, without diabetes at baseline, was resurveyed after 12 years. Logistic regression models were used to identify baseline risk factors that predicted the incidence of diabetes; a simple model that included only those risk factors as significant (P < 0.05) when adjusted for each other was developed. The coefficients from this model were transformed into components of a diabetes score. This score was tested in a Thai validation cohort of a different 2,420 individuals.

RESULTS

A total of 361 individuals developed type 2 diabetes in the exploratory cohort during the follow-up period. The significant predictive variables in the simple model were age, BMI, waist circumference, hypertension, and history of diabetes in parents or siblings A cutoff score of 6 of 17 produced the optimal sum of sensitivity (77%) and specificity (60%). The area under the receiver-operating characteristic curve (AUC) was 0.74. Adding impaired fasting glucose or impaired glucose tolerance status to the model slightly increased the AUC to 0.78; adding low HDL cholesterol and/or high triglycerides barely improved the model. The validation cohort demonstrated similar results.

CONCLUSIONS

A simple diabetes risk score, based on a set of variables not requiring laboratory tests, can be used for early intervention to delay or prevent the disease in Thailand. Adding impaired fasting glucose or impaired glucose tolerance or triglyceride and HDL cholesterol status to this model only modestly improves the predictive ability.

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.

Defining obesity by body mass index in the Thai population: an epidemiologic study

The objective of this study was to develop cut-off values and evaluate the accuracy of body mass index (BMI) in the definition of obesity in the Thai population. A cross-sectional, epidemiologic study in 340 men and 507 women aged 50 +/- 16 yr (mean +/- SD; range: 20-84 yr), were sampled by stratified clustering sampling method. Body composition, including percentage body fat (%BF), was measured by dual energy X-ray absorptiometry (GE Lunar Corp, Madison, WI). BMI was obtained by dividing weight (in kg) by height (in m2). The "golden standard "for defining obesity was %BF > or =25% in men and %BF > or =35% in women. The %BF-based prevalence of obesity in men and women was 18.8% and 39.5%, respectively. However, using the BMI cut-off of > or =30, only 2.9% of men and 8.9% of women were classified as obese. In the cubic regression model, BMI was a significant predictor of %BF, such that in men a BMI of 27 kg/m2 would predict a %BF of 25%, and in women a BMI of 25 kg/m2 would correspond to a %BF of 35%. The area under the receiver operating characteristic curve for BMI was approximately 0.87 (95% CI: 0.82-0.92) and 0.86 (95% CI: 0.83-0.90) in men and women, respectively. In conclusion, for the Thai population, BMI is a reasonably useful indicator of obesity; however, the cut-off values of BMI for diagnosing obesity should be lowered to 27 kg/m2 in men and 25 kg/m2 in women.

Association between bone mineral density and erythropoiesis in Thai children and adolescents with thalassemia syndromes

Increased marrow erythropoiesis in patients with thalassemia syndromes results in the expansion of bone marrow cavities and consequently decreases bone tissues, leading to osteoporosis. Whether the soluble transferrin receptor (sTfR), a marker of erythropoietic activity, correlates with the bone mineral density (BMD) in thalassemic patients has not previously been addressed. Forty-six children and adolescents with thalassemia syndromes, who were either not transfused or suboptimally transfused, were studied. BMD was determined by dual-energy X-ray absorptiometry. Blood samples were obtained in order to determine sTfR and hemoglobin. The patients were categorized into four groups: 1, beta-thalassemia/hemoglobin E (beta-thal/E) with transfusion-dependency (TD) (n = 18); 2, beta-thal/E with transfusion-independency (TI) (n = 15); 3, beta-thalassemia major (beta-major) (n = 6); 4, hemoglobin H (HbH) (n = 7). All patients had normal serum free thyroxine (FT4) and thyroid-stimulating hormone (TSH), and intact parathyroid hormone (PTH), serum calcium (Ca), phosphate (P), and 25-OH-vitamin D levels. The BMD of patients in the beta-major and beta-thal/E with TD groups were not significantly different. In comparison with the beta-major and beta-thal/E with TD groups, the beta-thal/E with TI and HbH groups had significantly higher BMD of the total body (TB), femoral neck (FN), and lumbar spine (LS), as well as higher levels of hemoglobin. In contrast, the sTfR levels of the beta-major, beta-thal/E with TI, and HbH groups were significantly lower than those of the beta-thal/E with TD group. The BMD of TB, FN, and LS was negatively correlated with the sTfR level, but positively correlated with the hemoglobin level. In conclusion, increased marrow erythropoiesis is one of the major determinants of reduced bone mass in thalassemic patients with either no transfusion or suboptimal transfusion.

Contribution of lean tissue mass to the urban-rural difference in bone mineral density

While the urban-rural difference in bone mineral density (BMD) has been shown in some, but not all, Western populations, such a difference and the reason for the difference is largely unknown, particularly in developing countries. This cross-sectional, epidemiologic study was designed to examine the hypothesis that differences in measures of body composition such as lean mass (LM) and fat mass (FM) contribute to the urban-rural difference in BMD. Lean mass, fat mass, lumbar spine and femoral neck BMD were measured by DXA (GE Lunar Corp, Wis.) in 411 urban (Bangkok city) and 436 rural (Khon Kaen province) Thai subjects, aged 20-84 years. Rural men and women had significantly higher LM and lower FM than their urban counterparts. In multiple linear regression analysis, age, LM, menopausal status (in women) and residence were independent determinants of BMD. After adjusting for age, menopause and LM, rural subjects were found to have significantly higher femoral neck BMD, but not lumbar spine BMD, than urban subjects. Furthermore, to alleviate the potential effect of multicolinearity of LM and FM, each rural subject was matched with each urban subject for FM and age, which resulted in 46 pairs of men and 91 pairs of women. In this matched-pair analysis, the femoral necks in rural men and women were, respectively, 7.3+/-2.1% (mean+/-SE; P<0.01) and 6.3+/-2.8% (P<0.02) higher than in urban men and women. The urban-rural difference in LM accounted for approximately 23 and 5% of the urban-rural difference in femoral neck BMD in men and women, respectively. These data are thus consistent with the hypothesis that the urban-rural difference in BMD at a weight-bearing site is in part associated with the urban-rural difference in lean mass.

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.

A specific haplotype in the 3' end of estrogen-receptor alpha gene is associated with low bone mineral density in premenopausal women and increased risk of postmenopausal osteoporosis

It is well established that the development of postmenopausal osteoporosis is under genetic influence. We have recently identified a synonymous single nucleotide polymorphism (SNP) in exon 8 of estrogen receptor-alpha (ERalpha) gene in the vicinity of the stop codon (G2014A) that is associated with an increased risk of postmenopausal osteoporosis. In the present study, we attempted to locate SNPs in the 3'-unstranslated region (3'UTR) of the ERalpha gene that are in linkage disequilibrium with the exon 8 SNP and assessed their utilization in the risk assessment of postmenopausal osteoporosis in 352 Thai postmenopausal women. The association with bone mineral density (BMD) in premenopausal women was also investigated in 202 premenopausal women. A C to A SNP 1,748 nucleotides distal to the end of the stop codon (C3768A) was identified. The C3768A SNP was not overrepresented in subjects with osteoporosis. However, the presence of the A-C haplotype allele based on the A2014 and C3768 alleles was significantly related to the risk of osteoporosis independently of age, body weight, the G2014A and C3768A SNPs (odds ratio 2.36, 95% CI 1.42-3.91). Moreover, the presence of the A-C haplotype allele was associated with lower femoral neck BMD in premenopausal women ( P =0.05). We concluded that a specific haplotype in the 3' end of the ERalpha gene is associated with lower BMD in premenopausal women and is associated with a higher risk of osteoporosis in postmenopausal women. It is likely that the haplotype allele exerts its influence on bone as early as during young adulthood to increase the risk of osteoporosis later in life.

The effect of cigarette smoking on the severity of periodontal disease among older Thai adults

BACKGROUND

The aim of this study is to determine the effect of cigarette smoking on the severity of periodontitis in a cross-sectional study of older Thai adults.

METHODS

The study population consisted of 1,960 subjects (age 50 to 73 years old). All subjects received both medical and dental examinations. Periodontal examinations, including plaque score, probing depth, and clinical attachment level, were done on all teeth present in two diagonal quadrants. Sociodemographic characteristics and smoking status were obtained by questionnaires. Multinomial logistic regression was used to address the association between cigarette consumption and mean clinical attachment level.

RESULTS

In this study population, 48.7% were non-smokers, 14.4% were current smokers, and 36.9% were former smokers. Current smokers had higher percentage of sites with plaque, deeper mean probing depth, and greater mean clinical attachment level than former smokers and non-smokers. The odds of having moderate and severe periodontitis for current smokers were 1.7 and 4.8 times greater than non-smokers, respectively. Former smokers were 1.8 times more likely than non-smokers to have severe periodontitis. Quitting smoking reduced the odds of having periodontitis. For light smokers (<15 packyear), the odds for severe periodontitis reverted to the level of non-smokers when they had quit smoking for > or =10 years. For moderate and heavy smokers (> or =15 packyear), the odds of having severe periodontitis did not differ from those of non-smokers when they had quit smoking for > or =20 years.

CONCLUSIONS

There was a strong association between cigarette smoking and the risk of periodontitis among older Thai adults. Quitting smoking appears to be beneficial to periodontal health.

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

Exogenous subclinical hyperthyroidism during adolescence: effect on peak bone mass

BACKGROUND

Chronic subclinical hyperthyroidism induced by suppressive doses of L-thyroxine (L-T4) therapy, so-called exogenous subclinical hyperthyroidism, may cause diminished bone mass in postmenopausal women. The effect of subclinical hyperthyroidism during childhood and adolescence on peak bone mass, however, has not been evaluated.

OBJECTIVE

To determine whether exogenous subclinical hyperthyroidism during adolescence, the period of critical bone mass acquisition, would reduce peak bone mass.

PATIENTS AND METHODS

Eighteen female adolescents and young adults with Hashimoto's thyroiditis and euthyroid goiter (aged 22.4 +/- 4.4 years) who had been treated with suppressive doses of L-T4, 127.5 +/- 23.7 microg/day, during adolescence (age at onset of subclinical hyperthyroidism, 14.2 +/- 1.5 years) for 6.3 +/- 3.4 years were enrolled in the study. Twenty-nine healthy female volunteers matched for age, weight, height and body mass index served as the controls. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry.

RESULTS

BMD of the lumbar spine, radius, Ward's triangle and total body were comparable in the two groups. In contrast, BMD of the femoral neck, trochanter and shaft of patients was slightly higher than those of controls. There were no correlations between BMD values and clinical parameters.

CONCLUSION

Exogenous subclinical hyperthyroidism during adolescence has no demonstrable detrimental effect on peak bone mass attainment.

Effect of urbanization on bone mineral density: a Thai epidemiological study

Background

The incidence of fractures in rural populations is lower than in urban populations, although the reason for this difference is unclear. This cross-sectional study was designed to examine the difference in bone mineral density (BMD), a primary predictor of fracture risk, between urban and rural Thai populations.

Methods

Femoral neck and lumbar spine BMD was measured by dual-energy X-ray absorptiometry (GE Lunar, Madison, WI) in 411 urban and 436 rural subjects (340 men and 507 women), aged between 20 and 84 years. Body mass index (BMI) was calculated from weight and height.

Results

After adjusting for age and body weight in an analysis of covariance model, femoral neck BMD in rural men and women was significantly higher than those in urban men and women (P < 0.001), but the difference was not observed at the lumbar spine. After stratifying by sex, age group, and BMI category, the urban-rural difference in femoral neck BMD became more pronounced in men and women aged <50 years and with BMI ≥ 25 kg/m².

Conclusions

These data suggest that femoral neck BMD in rural men and women was higher than their counterparts in urban areas. This difference could potentially explain part of the urban-rural difference in fracture incidence.

Biochemical markers of bone formation in Thai children and adolescents

The measurement of biochemical markers of bone turnover is essential in the study of skeletal metabolism in health and diseases. Due to variations in the rate of bone growth in different age groups and possible ethnic differences, age-specific reference ranges for biochemical markers should be established in a particular pediatric population. In this study, biochemical markers of bone formation, bone-specific alkaline phosphatase (BAP), and osteocalcin (OC) in healthy Thai children and adolescents aged 9 to 18 years were evaluated in relation to their ages and pubertal development. Serum BAP levels in boys increased with age and peaked at about 12 to 13 years. In contrast, there was a progressive decline of serum BAP levels with advancing age in girls older than 9 years. Serum OC also increased with age and reached a peak at ages 12 and 13 years in girls and boys, respectively. In addition, both serum BAP and OC levels also varied with pubertal stages. The BAP levels in boys increased sharply at pubertal stage 3 and decreased at pubertal stage 5. In girls, the BAP levels showed a fairly constant high level up to stage 3, followed by a remarkable decrease thereafter. The OC levels in boys increased sharply at pubertal stage 4 and decreased thereafter. In girls, OC started to increase at pubertal stage 3 with no subsequent changes. The levels of serum BAP and OC were higher in boys than in girls at pubertal stages 3 to 5 and at stages 2, 4, and 5, respectively. Moreover, only serum BAP level showed significant positive correlation with height velocity in both genders. In multiple regression analyses, gender, age, and pubertal stage were consistently correlated with both serum BAP and OC levels. In summary, male and female adolescents have different patterns of changes in biochemical markers of bone formation.

Schedule of taking calcium supplement and the risk of nephrolithiasis

BACKGROUND

Variation in the timing of calcium supplement may affect gastrointestinal absorption of both calcium and oxalate differently and may associate with variable risk of calcium oxalate nephrolithiasis. There are few human studies addressing specifically the appropriate time for taking calcium supplement. Therefore, this study was performed to compare calcium bioavailability and the risk of calcium oxalate stone formation for calcium supplement taken with meal vs. taken at bedtime.

METHODS

Thirty-two healthy male navy privates, 22.7 +/- 1.9 years old (mean +/- SD), who had normal renal function (serum creatinine less than 150 umol/L) and no history of renal stone, participated in the study. The subjects were randomly allocated into two groups of 16 each. Group A took 1 g of calcium carbonate with meal, 3 times/day; and group B took 3 g/day of calcium carbonate at bedtime. After taking the regimens for 1 week, followed by 1 month of washout period, crossover between both groups was done. The diet was controlled throughout the study. Twenty-four-hour urine collections for the determination of urinary constituents were obtained at baseline and after taking both regimens of calcium supplement. Activity product for calcium oxalate was determined to assess the risk of calcium oxalate stone formation.

RESULTS

Urinary excretions of calcium were significantly elevated above the baseline values when taking calcium supplement both with meal (3.48 +/- 2.13 mmol/day vs. 5.17 +/- 2.61 mmol/day, P < 0.05) and at bedtime (3.09 +/- 1.70 mmol/day vs. 5.08 +/- 2.34 mmol/day, P < 0.05). There was no difference between the two regimens in the urinary calcium excretions. The urinary oxalate was decreased significantly when the subjects took calcium supplement with meal compared with the corresponding baseline value (0.13 +/- 0.05 vs. 0.17 +/- 0.07 mmol/d, P= 0.01). In contrast, there was no alteration in urinary oxalate when calcium supplement was taken at bedtime compared to the baseline values (0.15 +/- 0.05 mmol/day vs. 0.15 +/- 0.06 mmol/day, P= 0.9). Compared with the corresponding baseline values, there was no significant increase in the activity product for calcium oxalate when taking calcium with meal (0.54 +/- 0.25 vs. 0.57 +/- 0.22, P= 0.54), but it was increased significantly when calcium supplement was taken at bedtime (0.47 +/- 0.21 vs. 0.72 +/- 0.27, P < 0.01).

CONCLUSION

Calcium supplement should be taken with meal in order to avoid increasing the risk of calcium oxalate nephrolithiasis.

Incomplete renal tubular acidosis and bone mineral density: a population survey in an area of endemic renal tubular acidosis

BACKGROUND

'Primary' osteoporosis has been associated with a high incidence of a renal acidification defect, incomplete renal tubular acidosis (iRTA). An acid loading test, to exclude the defect, has been recommended for inclusion in the work-up of osteoporosis. However, there is no community-based study to confirm its utility.

METHOD

A community-based survey was conducted in the Khon Kaen province, Thailand, between January and June, 2000. We randomly enrolled 361 apparently healthy adults, 146 men and 215 women, in this study. The bone mineral densities (BMDs) of the spine and femur were determined in all subjects. The diagnosis of iRTA was based on: normal serum electrolytes and one or both of first morning urinary pH >5.5 or the failure of an acid loading test to decrease it to >5.5. Dietary diaries, serum electrolyte tests and 24 h urine collections were obtained from all iRTA subjects.

RESULTS

There were 23 (6.4%) iRTA subjects in the population studied. The age, height, weight and calcium intake were comparable between iRTA and normal subjects, as were the BMDs of spine and femur. There was no difference between the two groups in the distributions of BMD with age for either area. Multiple regression analyses of the studied population demonstrated that age, body weight, duration of menopause and gender (only for the femoral neck) were independent variables that affected BMD.

CONCLUSION

Incomplete distal renal tubular acidosis alone was not associated with lower bone mass in this cohort. It may nevertheless be valuable to monitor serum electrolytes and BMD in patients with iRTA due to their tendency to develop intermittent metabolic acidosis.

Effects of physical activity and dietary calcium intake on bone mineral density and osteoporosis risk in a rural Thai population

The objective of the study was to determine the effects of modifiable risk factors on bone mineral density in postmenopausal Thai women. Dietary calcium intake (g/day), energy expenditure (kcal/day), and sunlight exposure (h/day) were assessed in 129 rural Thai women aged 63 years (range 50 to 84 years). Bone mineral density (BMD) at the femoral neck, lumbar spine, and distal radius were measured by dual-energy X-ray absorptiometry (DXA). The average dietary calcium intake was 236 +/- 188 g/day (mean +/- SD), while the energy expenditure was 2,118 +/- 656 kcal/day with 1.1 +/- 1.7 h of sunlight exposure. In multiple linear regression analysis, dietary calcium intake, energy expenditure, and years since menopause were significant and independent predictors of BMD at various sites. The three factors together accounted for between 35% and 45% of the variance of BMD. The prevalence of osteoporosis (defined as BMD T-scores < or =-2.5) was 33% at the femoral neck, 42% at the lumbar spine, and 35% at the distal radius. The risk of osteoporosis was higher in women with lower dietary calcium intake (< or =138 mg/day; prevalence rate ratio [PRR], 1.4; 95% confidence interval [CI], 1.0 to 1.9), lower energy expenditure (< or =1,682 kcal; PRR, 1.7; 95% CI, 1.2 to 2.3), and greater years since menopause (> or =6 years; PRR, 2.6; 95% CI, 1.2 to 5.8). The population attributable risk fraction of osteoporosis risk due to the three factors was 70%. These results suggest that in the Thai population, low dietary calcium intake and low physical activity together with advancing years since menopause were independent risk factors for low BMD.

Alteration of noncollagenous bone matrix proteins in distal renal tubular acidosis

Our previous report on bone histomorphometry in patients with distal renal tubular acidosis (dRTA) revealed decreased bone formation rate (BFR) when compared to healthy subjects. The abnormality improved significantly after alkaline therapy. The modest increase in osteoblastic surface, after correction of metabolic acidosis, could not explain the striking improvement in bone formation, suggesting additional influence of metabolic acidosis on osteoblast function and/or bone matrix mineralization. Osteoblasts and, to a lesser extent, osteoclasts synthesize and secrete bone matrix including type I collagen and various noncollagenous proteins (NCPs). Substantial evidence suggested diverse functions of NCPs related to bone formation, resorption, and mineralization. Metabolic acidosis, through its effect on bone cells, may result in an alteration in the production of NCPs. Our study examined bone histomorphometry with detailed analysis on the mineralization parameters and NCPs expression within the bone matrix of patients with dRTA before and after treatment with alkaline. Seven dRTA patients underwent bone biopsy at their initial diagnosis and again 12 months after alkaline therapy. Bone mineral density (BMD) and bone histomorphometry were obtained at baseline and after the treatment. The expression of NCPs was examined by immunohistochemistry, quantitated by digital image analysis, and reported as a percentage of area of positive staining or mineralized trabecular bone area. Alkaline therapy normalized the low serum phosphate and PTH during acidosis. The reduction in BMD at baseline improved significantly by the treatment. Bone histomorphometry demonstrated the increase in osteoid surface and volume without significant alteration after acidosis correction. In comparison to the normal subjects, osteoid thickness was slightly but insignificantly elevated. Osteoblast and osteoclast populations and their activities were suppressed. The reduction in mineral apposition rate and adjusted apposition rate were observed in conjunction with the prolongation of mineralization lag time. Alkaline therapy improved the mineralization parameters considerably. In addition to the increase in BFR relative osteoblast number after acidosis correction, osteocalcin expression in the bone matrix increased significantly from 16.7% to 22.3%. Six of seven patients had decreased osteopontin expression. In conclusion, the abnormal bone remodeling in dRTA is characterized by low turnover bone disease with some degree of defective mineralization. Alteration of NCPs expression suggested the effect of metabolic acidosis on bone cells. Alkaline therapy increased bone mass through the restoration of bone mineral balance and, perhaps, improved osteoblast function.

Propylthiouracil-Induced Sensorineural Hearing Loss Associated with Antineutrophil Cytoplasmic Antibodies

OBJECTIVE

To report the case of a young woman with Graves' disease in whom ototoxicity developed because of propylthiouracil (PTU)-induced antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis.

METHODS

We present the clinical findings, pertinent laboratory data, and follow-up course of a patient with Graves' disease and bilateral sensorineural hearing loss. We also provide a literature review regarding thionamide-induced ANCA-associated vasculitis.

RESULTS

In a 22-year-old Thai woman with Graves' disease, tinnitus, hearing impairment in the left ear (with progression to the right ear), and vertigo developed after 3 years of therapy with PTU. Audiograms showed bilateral sensorineural hearing loss with cochlear lesions. She also had low-grade fever, intermittent chronic abdominal pain, weight loss, polyarthralgia, and conjunctivitis. An indirect immunofluorescence test for ANCA was positive. The hearing impairment and tinnitus were gradually reduced after PTU withdrawal and corticosteroid and azathioprine treatment. Definitive therapy by subtotal thyroidectomy was subsequently performed and yielded good results.

CONCLUSION

This rare case of PTU-induced ANCA-associated vasculitis manifested with ototoxicity in combination with systemic involvement.

Differential associations of residual estradiol levels with bone mineral density and serum lipids in postmenopausal women with osteoporosis

OBJECTIVES

To examine the associations of residual endogenous estradiol (E2) to bone mineral density (BMD) and lipid concentrations in elderly women.

METHODS

Subjects consisted of 59 elderly postmenopausal women with vertebral or femoral osteoporosis. BMD was measured at L2-4 and femoral neck by dual-energy X-ray absorptiometry (DEXA). Residual E2 concentrations were assessed by a sensitive radioimmunoassay. Data were expressed as mean +/- S.E.M.

RESULTS

The age of the subjects was 65.2 +/- 0.8 years with 18.9 +/- 1.0 years postmenopausal. The mean residual E2 concentration was 6.0 +/- 0.5 pg/ml. There was a correlation between E2 levels and BMD at L2-4 (r = 0.32, P < 0.01) while no association was found at the femoral neck. The association between E2 and L2-4 BMD persisted after adjusting for years since menopause and body weight (r = 0.33, P < 0.05). With regard to serum lipid concentrations, no association of serum total cholesterol, LDL-cholesterol, HDL-cholesterol or triglyceride concentrations with residual E2 was found.

CONCLUSIONS

Our findings confirm the role of residual endogenous E2 in the determination of bone mass in postmenopausal women with osteoporosis. The effect of residual E2 appears to be skeletal specific and possess no association with serum lipid concentrations.

Efficacy of intermittent low dose alendronate in Thai postmenopausal osteoporosis

Alendronate has been proven to be effective in the prevention and treatment of postmenopausal osteoporosis with the recommended daily dose of 10 mg. However, a constraining requirement for dosing limited its general acceptance in treatment. Since alendronate is potent and has a long half-life, weekly administration of alendronate in lower total doses might be safer and more convenient. The purpose of this study was to determine the efficacy of low dose once-weekly 20 mg alendronate in Thai postmenopausal women with osteoporosis. Thirty-nine postmenopausal women with osteoporosis received alendronate 20 mg once a week plus 750 mg elemental calcium daily. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at baseline and 6 and 12 months after treatment. Serum C-terminal telopeptide of type I collagen (CTx-I) was measured by electrochemiluminescence immunoassay at baseline and 3 months after treatment. By the end of 1 year, once weekly 20 mg alendronate significantly increased vertebral BMD (+6.2%, p < 0.001 vs baseline) from baseline whereas there was a reduction of 60.7% in serum CTx-I at 3 months. However, the BMD at femur did not increase significantly (+0.64%). Conclusion. Low-dose intermittent once-weekly 20 mg alendronate was effective, cost saving and had a good safety profile in increasing vertebral BMD and stabilizing BMD at the femoral neck in postmenopausal osteoporosis.

The implication of assessing a polymorphism in estrogen receptor alpha gene in the risk assessment of osteoporosis using a screening tool for osteoporosis in Asians

Both genetic and environmental factors interact to determine bone mass and the risk for developing postmenopausal osteoporosis. Recently, an Asian-specific tool, the Osteoporosis Self-Assessment Tool for Asians (OSTA), has been developed to assess the risk of osteoporosis in women. An index is calculated by multiplying the difference in body weight in kilograms and age in years by 0.2 and disregarding the decimal digits. The risk of osteoporosis is classified as high, intermediate or low according to the OSTA index less than -4, -4 to -1 and greater than -1. In the present study we examined how a single nucleotide polymorphism (SNP) in exon 8 of the estrogen receptor alpha (ERalpha) gene affected the predictive value of the OSTA index. Subjects consisted of 358 postmenopausal women who were at least 55 years old. BMDs were measured by DXA, and the SNP in the ERalpha gene was assessed by PCR-RFLP. When considering both the OSTA index and ERalpha genotype in a logistic regression model, it was found that both the OSTA index and the ERalpha genotype independently contributed to the risk of osteoporosis. The odds ratios were 1.58 (95% CI 1.26-1.91) and 2.51 (95% CI 1.42-4.44) for one unit decrement in the OSTA index and each copy of the A allele of the ERalpha genotype, respectively. The joint effect conformed more to a multiplicative model of interaction than an additive model. This suggests that persons with the high-risk genotype are at far greater risk of developing osteoporosis with advancing age or decreasing body weight, the two variables from which the OSTA index is derived. Targeting preventive measures for osteoporosis subjects with risk factors and also disease-susceptibility alleles is likely to be more cost effective.

Abnormalities in bone mineral density and bone histology in thalassemia

This study demonstrated that there was extensive iron staining on trabecular surface and marked reduction in trabecular bone volume without significant alteration in bone formation and bone resorption rates as well as significant reduction in bone mineral density in 18 thalassemic patients. Serum IGF-I was reduced and may modulate the reduction of bone mass.

INTRODUCTION

Bone histomorphometric studies in thalassemia to show alterations in bone histology and their relationship to biochemical parameters are very limited. Therefore, this study was systematically conducted to determine the alterations in thalassemia patients.

METHODS

Serum biochemical parameters, trans-iliac crest bone biopsy, and determination of bone mineral density of femur and lumbar spine were done in 18 thalassemic patients (10 females and 8 males).

RESULTS

Serum osteocalcin, carboxy terminal teleopeptide fragment of type I collagen, and parathyroid hormone levels were within normal limits, but serum 25(OH) vitamin D (19.3 +/- 1.6 ng/ml) and 1,25(OH)2 vitamin D (33.77 +/- 1.51 pg/ml) levels were decreased. Serum insulin-like growth factor I (IGF-I; 145.2 +/- 20 ng/ml) was suppressed, whereas serum ferritin (1366.6 +/- 253.9 ng/ml) was markedly elevated. Reduced bone mineral density was found in all studied areas. Trabecular bone volume was significantly decreased (16.65 +/- 1.12%), whereas bone formation rate, eroded surface, and other bone histomorphometric parameters were within normal limits. The trabecular bone volume varied significantly with bone mineral density of total femur (r = 0.48, p = 0.04). There was an extensive stainable iron surface on the mineral front (9-60%). Significant correlation between serum IGF-I, serum ferritin, stainable iron surface, and bone mineral density, lumbar spine, and total femur were found. Serum IGF-I correlated with trabecular bone volume (r = 0.6, p = 0.03), inversely with both serum ferritin level (r = -0.6, p < 0.01), and inversely with stainable iron surface (r = -0.53, p = 0.02). Multiple regression analysis demonstrated that IGF-I was the only independent variable that determined bone mineral density of lumbar spine and total femur.

CONCLUSION

Low bone mineral density and reduced trabecular bone volume with extensive iron deposition are the predominant findings in thalassemic patients. There was no evidence of increased bone resorption or mineralization defect. A reduction in circulatory IGF-I may modulate the reduction of bone mass.