Aparna Sastry

Dyslipidemia in subclinical hypothyroidism in an Indian population.

OBJECTIVES In view of inconsistent reports on the prevalence of dyslipidemia in subclinical hypothyroidism (SCH), we studied lipid abnormalities in Indian subjects with SCH. DESIGN AND METHODS A cross sectional study of 5343 subjects divided in two groups, Group-1 (age≤18 years) and Group-2 (age>18 years) was undertaken. They were further subdivided on the basis of their thyroid functional status: Normal (Control); SCH with TSH≤10.0mIU/L (SCH-1); and SCH with TSH>10mIU/L (SCH-2). RESULTS Prevalence of SCH was 14.7%. The only lipid abnormality in children and adolescents was low HDL in subjects with TSH>10mIU/L compared with controls. Serum total cholesterol (TC), and LDL cholesterol (LDL) were significantly higher in adults with TSH>10mIU/L compared to controls. There were no significant changes in lipid parameters in subjects with SCH having TSH≤10.0mIU/L, compared to controls. Serum TSH was positively and FT3 and FT4 were negatively correlated with TC and LDL. CONCLUSIONS Atherogenic lipid abnormalities were observed in adult subjects with SCH-2 (TSH>10.0mIU/L), and not in subjects with SCH-1 who had TSH≤10.0mIU/L in Indian population.

Reference range of thyroid hormones in normal Indian school‐age children

Objective  There is an ongoing debate on narrowing the TSH reference range in adults. In view of the scarce data on normal values of thyroid function tests in children from India, we planned to establish a reference range for thyroid hormones in school‐age children.

Relationship of Body Fat and Its Distribution With Bone Mineral Density in Indian Population

Obesity has been associated with increased bone mineral density (BMD). There is evidence of differential effect of regional fat on BMD. Hence, we undertook this study to evaluate the correlation between total body fat and its distribution with BMD in nonobese (mean body mass index: 25.0 ± 4.7 kg/m²) Indian adult volunteers. A total of 2347 participants (men: 39.4% and women: 60.6%) included in this cross-sectional study were divided according to sex and age. Fasting blood samples were drawn for biochemical parameters. Percent total body, truncal, and leg fat and BMD at lumbar spine, femur, and forearm were measured by dual-energy X-ray absorptiometry. The BMD at all sites (radius, femur, and spine) increased from lowest to highest quartiles of percent body fat. Percent truncal fat was positively correlated with BMD at all sites in both sexes, except for femoral neck in men, where it had negative correlation. Percent leg fat was positively related with BMD at all sites in premenopausal women, and spine and radius BMD in postmenopausal women. However, in men, it had negative correlation with femoral neck BMD. On multiple regression analysis, regional fat had positive association with BMD at all sites after adjusting for age, sex, lean mass index, 25-hydroxyvitamin D, and intact parathyroid hormone levels. Leg-to-total body fat ratio was negatively associated with BMD at all sites in men and pre- and postmenopausal women. Percent total body and regional fat have positive association with BMD at all sites in men and women.

Reference intervals of serum calcium, ionized calcium, phosphate and alkaline phosphatase in healthy Indian school children and adolescents.

OBJECTIVE To develop age- and sex-specific reference interval of serum total calcium, ionized calcium, inorganic phosphates and alkaline phosphatase in healthy Indian children in the age group of 6-17 years. DESIGN AND METHOD Subjects for this study were selected from the schools of Delhi. The final analysis included 3,327 children in the age group of 6-17 years (1707 boys; 1620 girls). RESULTS The mean, standard deviation, 5th, 25th, 50th, 75th, 90th, 95th and 97th centile values of biochemical parameters for boys and girls are presented. All these parameters were significantly higher in boys than girls except serum ionized calcium. Serum total calcium (r -0.1362, p<0.001), serum inorganic phosphate (r -0.45, p<0.001) and serum alkaline phosphatase (r -0.5587, p<0.001) have shown inverse relationship with age. CONCLUSIONS Reference interval of selected biochemical parameters for healthy Asian-Indian children in the age group of 6-17 years is presented.

The evolution of thyroid function with puberty

Objective  This study was planned to describe thyroid functional status in different stages of puberty.

Reference intervals of serum lipid profile in healthy Indian school children and adolescents

OBJECTIVE To develop age and sex specific reference intervals of serum lipid parameters in healthy Indian children in the age group of 6-17 years. PARTICIPANTS Study subjects were selected from the schools of Delhi. Children with BMI either in overweight or obese category were excluded to generate reference intervals. The final analysis included 3076 children with BMI in normal range for age. RESULTS The mean±SD, 3rd, 10th, 25th, 50th, 75th, 90th and 97th centile values of lipid parameters are presented. All these parameters were significantly higher in girls than in boys. About 89.2% subjects had total cholesterol in acceptable range while 9.1% had borderline elevated and 1.5% had elevated TC. Optimal serum triglyceride levels were seen in 45.1% subjects while optimal levels of HDL cholesterol were seen in 0.3% subjects only. CONCLUSIONS Reference intervals of serum lipid parameters for healthy Indian children (6-17 years) are presented.

Thyroid status two decades after salt iodization: country-wide data in school children from India.

Objective  Country‐wide evaluation of thyroid disorders in school children following two decades of universal salt iodization (USI) has not been carried out till date. This study was planned with aim to assess thyroid status of school children two decades after the launch of USI programme.

Establishment of Age-Specified Bone Mineral Density Reference Range for Indian Females Using Dual-Energy X-Ray Absorptiometry

We undertook this study to establish age-specified bone mineral density (BMD) reference range for Indian females using dual-energy X-ray absorptiometry. BMD at multiple skeletal sites was measured in 2034 healthy women aged 18--85yr. The effect of anthropometry and biochemical parameters on BMD was determined. Peak BMD was observed between 30 and 35yr at the hip, lumbar spine, and radius. Significant positive correlation of height and weight with BMD was observed at 33% radius, femur neck, and lumbar spine, whereas significant negative correlation was seen between serum alkaline phosphatase (ALP) and serum parathyroid hormone levels with BMD at aforementioned sites. On multivariate regression analysis, age, weight, and serum ALP were the most consistent contributors to variance in the BMD. Compared with age-matched US females, BMD of lumbar spine was significantly lower for our subjects in all age groups. Prevalence of osteoporosis among women aged older than 50yr was significantly higher based on Caucasian T-scores as opposed to using peak BMD/standard deviation values from the population under review at lumbar spine but not at femoral neck.

Reference range of thyroid function (FT3, FT4 and TSH) among Indian adults

OBJECTIVES To generate thyroid hormone reference norms using electro-chemiluminescence technique. DESIGN AND METHODS Cross sectional study on apparently normal 4349 Delhi adults (18-86 years). Predetermined exclusion criteria (goiter, hypoechogenicity or nodularity on ultrasound, elevated anti-thyroid peroxidase antibody, hypo or hyperthyroidism and family history of thyroid dysfunction) excluded 2433 subjects leaving 1916 (916 males and 1000 females) as the reference population. RESULTS Mean age and BMI of the reference population were 41.2 ± 18.1 years and 24.5 ± 4.4 kg/m(2) respectively. Median urinary iodine excretion was 233.6 μg/L (79-458;3rd-97th centile). The population was categorized into various age groups (18-30, 31-40, 41-50, 51-60, 61-70 and ≥ 70 years). Overall FT3 and FT4 values in the reference population irrespective of age, ranged from 2.4-8.8 (mean 4.6 ± 0.9) pmol/L and 10.1-24.8 (mean 15.40 ± 2.0) pmol/L, respectively. Mean TSH value in the reference population was 2.2 ± 0.9 mIU/L which was significantly lower than that of total population (3.8 ± 6.1; p<0.001). CONCLUSION FT3 values were observed to be significantly higher in men than women (p=0.001). The centiles (3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th and 97th) of FT3, FT4 and TSH were derived for reference purposes in Indian adults. This community based study in Indian adults has established mean reference intervals for FT3, FT4 and TSH for different age groups for both sexes separately using strict exclusion criteria. These can be used as reference norms for Indian adults.