ACTA ENDOCRINOLOGICA (BUC)

Background. Dual-energy X-ray absorptiometry (DXA) allows measurement of whole body (WB) and regional bone mineral content (BMC) and density (BMD). Objective. To measure WB and regional bone area, BMC and BMD (arms, legs, ribs and pelvis) in women of different ages. Subjects and Methods. 140 women participated (age range 20-75 yrs). Three subgroups were built: 20-44 yr (30 premenopausal women), 45-59 (80 women), and 60-75 (30 women). WB DXA was performed on a Hologic QDR 4500 A bone densitometer (Hologic Inc., Bedford MA). WB BMD T-scores were calculated by using the manufacturerprovided and the NHANES 1999-2004 reference databases, while the WB BMC Z-scores - based on the latter. Statistical analysis was performed on an IBM SPSS Statistics 19.0 for Windows platform (Chicago, IL). Results. WB BMC and BMD Z-scores were consistently lower than the reference databases showing a difference of about 0.4 – 0.5 SD. The arms, legs and ribs lost more BMC after the age of 50-55, while the pelvis – much earlier. The total decreases in BMC were highest in the pelvis (26.36 %), followed by the arms (16.81 %) and whole body (15.91 %), while the bone area decreased mostly in the pelvis (13.23 %). Conclusion. The age-related declines in regional BMC, bone areas and BMD follow different patterns in appendicular and axial bones.

Objective. To describe the correlations between serum 25(OH) vitamin D and anthropometric and metabolic parameters in adult outpatients of both sexes with different BMI coming from an urban community. Subjects and Methods. 264 subjects referred for obesity assessment participated – 109 men and 155 women (20-60 years). Body weight and height, waist circumference (WC), blood pressure were recorded. Body composition was assessed by bioelectrical impedance (BIA) on a Tanita BC 420 MA analyzer (Tanita Inc., Japan). Serum 25(OH)D Total, Insulin, High-sensitivity C-reactive protein, blood glucose, total, HDL-cholesterol and triglycerides were measured. The insulin resistance index was calculated (HOMA-IR). Participants with BMI>25.0 kg/m2 underwent standard 75 g OGTT. Statistical analysis was performed on an IBM SPSS Statistics 19.0 for Windows platform (Chicago, IL). Results. Normal weight was found in 27.2 % of the participants, 24.6 % had overweight, 29.2 % -class I obesity, and 18.9 % – class II or III. Vitamin D was weakly and inversely correlated to different variables in the whole group – such as weight, WC, WC/Height, % body fat and HOMA-IR index (r=-0.231, -0.283, -0.307, -0.339, -0.328 respectively, all p<0.001). Building subgroups based on BMI led to loss of significance. Backward analysis revealed Total-C/LDL-C ratio, and LDL-C/HDL-C ratio as strongest predictors of serum vitamin D (p=0.001; R2=0.204). Conclusion. The association of vitamin D with blood pressure, plasma lipids, glucose and insulin is very weak on an individual level. However, several obesity indices (WC, WC/height ratio, % Body fat from BIA) might be used as a screening tool for subjects at risk for vitamin D deficiency.