INTRODUCTION Epidemiological data on vitamin D status in the Polish population are limited. OBJECTIVES The aim of the study was to evaluate the vitamin D status in a representative group of adult inhabitants of 22 Polish cities, based on the analysis of serum 25-hydroxyvitamin D [25(OH)D] levels. PATIENTS AND METHODS This cross-sectional study included a total of 5775 adult volunteers (4464 women; 1311 men; mean age, 54.0 ±15.9 years; range, 15.6-89.8 years), who were enrolled and examined through late winter and spring 2014. Serum concentrations of 25(OH)D were determined using the Liaison XL system (DiaSorin; CLIA method). Demographic and anthropometric data were also analyzed. RESULTS The mean 25(OH)D concentration in the studied population was 18.0 ±9.6 ng/ml; 65.8% of the patients had 25(OH)D levels of less than 20 ng/ml; 24.1% had suboptimal levels of 20 to 30 ng/ml; and only 9.1% demonstrated the optimal levels of 30 to 50 ng/ml. In 89.9% of the studied population, 25(OH)D levels of less than 30 ng/ml were found. Obesity, defined as body mass index (BMI) over 30 kg/m2, was associated with lower 25(OH)D levels compared with normal weight (15.8 ±8.5 vs 18.5 ±9.7 ng/ml; P <0.0001). Lower 25(OH)D levels were observed in men, younger individuals, and individuals with excess body weight and higher BMI. CONCLUSIONS The results of our study, which involved the most representative sample size of Polish adults, support the previously reported data on vitamin D status. The levels of 25(OH)D determined for adults in our study demonstrate that the majority of the Polish population is vitamin D deficient, at least during winter and spring, and that preventive or interventional strategies must be considered to improve the vitamin D status in Poland.

Quantitative ultrasound of the heel captures heel bone properties that independently predict fracture risk and, with bone mineral density (BMD) assessed by X-ray (DXA), may be convenient alternatives for evaluating osteoporosis and fracture risk. We performed a meta-analysis of genome-wide association (GWA) studies to assess the genetic determinants of heel broadband ultrasound attenuation (BUA; n = 14 260), velocity of sound (VOS; n = 15 514) and BMD (n = 4566) in 13 discovery cohorts. Independent replication involved seven cohorts with GWA data (in silico n = 11 452) and new genotyping in 15 cohorts (de novo n = 24 902). In combined random effects, meta-analysis of the discovery and replication cohorts, nine single nucleotide polymorphisms (SNPs) had genome-wide significant (P < 5 × 10⁻⁸) associations with heel bone properties. Alongside SNPs within or near previously identified osteoporosis susceptibility genes including ESR1 (6q25.1: rs4869739, rs3020331, rs2982552), SPTBN1 (2p16.2: rs11898505), RSPO3 (6q22.33: rs7741021), WNT16 (7q31.31: rs2908007), DKK1 (10q21.1: rs7902708) and GPATCH1 (19q13.11: rs10416265), we identified a new locus on chromosome 11q14.2 (rs597319 close to TMEM135, a gene recently linked to osteoblastogenesis and longevity) significantly associated with both BUA and VOS (P < 8.23 × 10⁻¹⁴). In meta-analyses involving 25 cohorts with up to 14 985 fracture cases, six of 10 SNPs associated with heel bone properties at P < 5 × 10⁻⁶ also had the expected direction of association with any fracture (P < 0.05), including three SNPs with P < 0.005: 6q22.33 (rs7741021), 7q31.31 (rs2908007) and 10q21.1 (rs7902708). In conclusion, this GWA study reveals the effect of several genes common to central DXA-derived BMD and heel ultrasound/DXA measures and points to a new genetic locus with potential implications for better understanding of osteoporosis pathophysiology.

It is hypothesized that primary hypertension (PH) is a disorder with origins in childhood linked to, at least in part, aberrations of growth and maturation processes. To evaluate the possible relation between the rate of biological maturity and development of PH, bone age (BA) assessments on the basis of dual x-ray absorptiometry–derived hand scans were performed in 54 newly diagnosed children and adolescents with PH and 54 healthy controls matched for body mass index (BMI), age and sex. Chronological age (CA), body height (in centimeters), body weight (in kilograms), BMI (in kilograms per meter squared), and blood pressure were assessed. Healthy controls had a mean BA of 14.7±2.3 years that was not significantly different from their mean CA of 14.2±2.1 years. In the PH group, the BA of 16.0±2.0 years was higher by 1.9±0.9 years compared with their CA of 14.1±2.0 years ( P <0.0001). The magnitude of acceleration of skeletal maturation (BA-CA) and its prevalence (88.9%) were significantly higher in PH compared with BMI-matched controls (37.0%; χ ² =31.4; P <0.0001). BA-CA values of PH patients were higher by 1.24 years in normal weight ( P <0.0001), 1.80 years in overweight ( P <0.01), and 1.40 years in obese ( P <0.0001) subgroups of BMI z score–matched controls. Stepwise regression revealed that predictors of blood pressure status from normotension through prehypertension stages 1 and 2 of hypertension were BA-CA (β=0.530; P <0.0.001), height (β=−0.379; P <0.01), and CA (β=0.298; P <0.05; R ² =0.43). In conclusion, irrespective of BMI, advanced biological maturation should be considered as an independent marker for the development of hypertension.

The optimal vitamin D intake for nursing women is controversial. Deterioration, at least in bone mass, is reported during lactation. This study evaluated whether vitamin D supplementation during lactation enhances the maternal and infant’s vitamin D status, bone mass and body composition. After term delivery, 174 healthy mothers were randomized to receive 1200 IU/d (800 IU/d+400 IU/d from multivitamins) or 400 IU/d (placebo+400 IU/d from multivitamins) of cholecalciferol for 6 months while breastfeeding. All infants received 400 IU/d of cholecalciferol. Serum 25-hydroxyvitamin D [25(OH)D], iPTH, calcium, urinary calcium, and densitometry were performed in mother-offspring pairs after delivery, and at 3 and 6 months later. A total of 137 (79%) (n = 70; 1200 IU/d, n = 67; 400 IU/d) completed the study. 25(OH)D was similar in both groups at baseline (13.7 ng/ml vs. 16.1 ng/ml; P = 0.09) and at 3 months (25.7 ng/ml vs. 24.5 ng/ml; P = 0.09), but appeared higher in the 1200 IU/d group at 6 months of supplementation (25.6 ng/ml vs. 23.1 ng/ml; P = 0.009). The prevalence of 25(OH)D 20 ng/ml in nursing women, while 1200 IU/d appeared more effective, but had no effect on breastfed offspring vitamin D status, or changes in the bone mass and the body composition observed in both during breastfeeding. ClinicalTrials.gov NCT01506557