Evidence of a significant vitamin D deficiency among 9-13-year-old Polish children: results of a multicentre study.

PURPOSE: To evaluate the extent to which the population of Polish preadolescents is vitamin D deficient and to assess seasonal variations in vitamin D status. PARTICIPANTS AND METHODS: A total of 720 healthy children aged 9-13 years (409 girls, 311 boys) residing in 6 representative geographical locations in Poland were studied. A parental-assisted questionnaire provided data on nutritional habits, vitamin D supplements and sun exposure. Serum concentration of 25-hydroxyvitamin was determined twice, after the winter in March and after the summer in October. RESULTS: In March, vitamin D deficiency (25-50 nmol/L) was found in 64%, and severe deficiency (< 25 nmol/L) in 20.2% of children. In October, the deficiency and severe deficiency were still noticed in 25.9 and 0.1% of children, respectively. The mean serum concentration of 25-OHD was 52% higher in October (55.4 ± 14.0 nmol/L) than in March (36.4 ± 13.5 nmol/L), (p < 0.01). In children with 25-OHD < 50 nmol/L in March, their 25-OHD concentration increased by 64% through March to October (32.5 ± 8.2 vs. 53.2 ± 7.9 nmol/L, p < 0.01). An association was found between 25-OHD concentration and regular consumption of vitamin D supplements, cod-liver oil and fish. CONCLUSIONS: The majority of preadolescent Polish boys and girls show vitamin D deficiency after the winter period, although a distinct amelioration over summertime is found in this age group. There is a need to implement effective prevention and intervention strategies in the management of vitamin D deficiency among schoolchildren in Poland, with the supplementation throughout the entire year.

Requirement for vitamin D supplementation in patients using photoprotection: variations in vitamin D levels and bone formation markers.

BACKGROUND: Avoiding sun exposure is obligatory in photodermatoses; however, the need for oral supplementation with vitamin D appears unrecognized. The aim of the study was to investigate the seasonal variation of vitamin D level and bone formation markers in healthy individuals and to compare it with vitamin D status in patients using photoprotection. METHODS: Thirty-four healthy inhabitants of the Lodz region, Poland, a country in central Europe (51° and 52° north latitudes), were examined at the baseline visit within 2 weeks of peak sun exposure during recreational activity on vacation, after 8, and after 16 weeks. The group of patients using photoprotection comprised 104 patients with systemic lupus erythematosus. Serum 25(OH) vitamin D, procollagen type I N-terminal propeptide (PINP), and osteocalcin levels were measured. RESULTS: The serum 25-hydroxyvitamin D concentration was lower and vitamin D deficiency more common in patients using photoprotection than in healthy individuals during the warm and the cold season (P < 0.05). In healthy individuals, vitamin D deficiency was more prevalent after 8 and 16 weeks than at baseline assessment (P < 0.001). PINP level was 39.56 (30.51-53.22) ng/ml, and elevated in 50% of individuals, whereas osteocalcin was 18.88 (13.52-21.33) ng/ml, and within reference range. CONCLUSIONS: Diagnoses of vitamin D deficiency and oral supplementation in patients using photoprotection need to be included in practice. Peak 25-hydroxyvitamin D levels are probably achieved from vitamin D skin synthesis during the summertime and fall over time, starting from August. Elevated levels of PINP appear in line with the process of bone remodeling related to age.

Impact of vitamin D supplementation during lactation on vitamin D status and body composition of mother-infant pairs: a MAVID randomized controlled trial.

OBJECTIVE: 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. DESIGN AND METHODS: 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. RESULTS: 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 was comparable between groups at baseline (71% vs. 64%, P = 0.36) but lower in the 1200 IU/d group after 3 months (9% vs. 25%, P = 0.009) and 6 months (14% vs. 30%, P = 0.03). Maternal and infants' iPTH, calciuria, bone mass and body composition as well as infants' 25(OH)D levels were not significantly different between groups during the study. Significant negative correlations were noted between maternal 25(OH)D and fat mass (R =  -0.49, P = 0.00001), android fat mass (R = -0.53, P = 0.00001), and gynoid fat mass (R = -0.43, P = 0.00001) after 6 months of supplementation. CONCLUSIONS: Vitamin D supplementation at a dose of 400 IU/d was not sufficient to maintain 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. TRIAL REGISTRATION: ClinicalTrials.gov NCT01506557.

Polish guidelines for the diagnosis and management of osteoporosis: a review of 2013 update.

To decrease the risk of osteoporotic fractures in Poland, the Multidisciplinary Osteoporotic Forum has set up a joint Working Group including the representatives of the Polish Associations of Orthopedics and Traumatology, Rehabilitation, Gerontology, Rheumatology, Family Medicine, Diabetology, Laboratory Diagnostics, Andropause and Menopause, Endocrinology, Radiology, and the STENKO group as well as experts in the fields of rheumatology, obstetrics, and geriatrics to update the Polish guidelines for the diagnosis and management of osteoporosis in men and postmenopausal women in Poland. The assessment of fracture risk and intervention thresholds was made using the FRAX® calculation tool for Poland. The strength of recommendations was evaluated according to the principles of the Scottish Intercollegiate Guidelines Network and the results have been approved by national consultants. Finally, the Working Group has formulated the updated guidelines and recommended two -step diagnostic and therapeutic procedures. The first stage applies to family physicians or general practitioners and involves the assessment of fracture risk using the FRAX®-BMI to identify patients at high risk of fractures. An osteoporotic fracture remains an absolute indication both for the general practitioner and specialist to implement treatment. At the second stage, the specialist (in an osteoporosis or other specialty clinic) should review the primary or secondary causes of fracture risk, confirm the diagnosis, and introduce an appropriate treatment and monitoring. In patients (men aged >50 years and postmenopausal women) without low-energy fractures, the absolute risk of fractures exceeding 10% should be considered an indication for treatment. The Polish guidelines were compared with other international guidelines in terms of diagnostic measures, pharmacotherapy, as well as calcium and vitamin D supplementation.

Practical guidelines for the supplementation of vitamin D and the treatment of deficits in Central Europe - recommended vitamin D intakes in the general population and groups at risk of vitamin D deficiency.

INTRODUCTION: Adequate Vitamin D intake and its concentration in serum are important for bone health and calcium-phosphate metabolism as well as for optimal function of many organs and tissues. Documented trends in lifestyle, nutritional habits and physical activity appear to be associated with moderate or severe Vitamin D deficits resulting in health problems. Most epidemiological studies suggest that Vitamin D deficiency is prevalent among Central European populations. Concern about this problem led to the organising of a conference focused on overcoming Vitamin D deficiency. METHODS: After reviewing the epidemiological evidence and relevant literature, a Polish multidisciplinary group formulated theses on recommendations for Vitamin D screening and supplementation in the general population. These theses were subsequently sent to Scientific Committee members of the 'Vitamin D - minimum, maximum, optimum' conference for evaluation based on a ten-point scale.With 550 international attendees, the meeting 'Vitamin D - minimum, maximum, optimum' was held on October 19-20, 2012 in Warsaw(Poland). Most recent scientific evidence of both skeletal and non-skeletal effects of Vitamin D as well as the results of panellists' voting were reviewed and discussed during eight plenary sessions and two workshops. RESULTS: Based on many polemical discussions, including post-conference networking, the key opinion leaders established ranges of serum 25-hydroxyVitamin D concentration indicating Vitamin D deficiency [< 20 ng/mL (< 50 nmol/L)], suboptimal status [20-30 ng/mL(50-75 nmol/L)], and target concentration for optimal Vitamin D effects [30-50 ng/mL (75-125 nmol/L)]. General practical guidelines regarding supplementation and updated recommendations for prophylactic Vitamin D intakes in Central European neonates, infants, children and adolescents as well as in adults (including recommendations for pregnant and breastfeeding women and the elderly) were developed. CONCLUSIONS: Improving the Vitamin D status of children, adolescents, adults and the elderly must be included in the priorities of physicians,healthcare professionals and healthcare regulating bodies. The present paper offers elaborated consensus on supplementation guidance and population strategies for Vitamin D in Central Europe.

Impact of vitamin D supplementation on markers of bone mineral metabolism in term infants.

UNLABELLED: 25-Hydroxyvitamin D (25OHD) may influence bone turnover. We compared the dynamics of bone markers in 30 infants on vitamin D supplementation (≅550 IU/day) with different degrees of hypovitaminosis D (25OHD <11 ng/ml - deficiency vs. ≥ 11 <20 ng/ml - insufficiency). Baseline and follow-up (after 10 weeks), 25OHD, 1,25-dihydroxyvitamin D (1,25(OH)(2)D), alkaline phosphatase (ALP), PTH, osteocalcin (OC), N-terminal propeptide of type I procollagen (PINP), C-terminal telopeptide of type I collagen (CTX), and amino-terminal propeptide of C-type natriuretic peptide (NT-proCNP) were measured. None of the newborns had craniotabes, hypocalcemia or hyperparathyroidism. The median (Q1;Q3) 25OHD increased from a baseline of 8.45 (7;11.9) ng/ml to 54.6 (34.7;67.3) ng/ml (p<0.001). The baseline 25OHD negatively correlated with total increment of 25OHD (r=-0.54; p=0.002). There were changes in ALP (241 vs. 331 IU; p<0.001), 1,25(OH)(2)D (48 vs. 95.5 pg/ml, p<0.001), OC (88.8 vs. 159.1 ng/ml, p<0.001), PINP (3886 vs. 2409 ng/ml; p<0.001), CTX (1.6 vs. 1.1 ng/ml; p<0.001), and NT-proCNP (75.1 vs. 35.1 pmol/l; p<0.001). Vitamin D deficient infants at baseline, compared to the insufficient group, revealed significantly higher percentage changes for 25OHD (745% vs. 167%, p<0.0001), OC (113% vs. 40%, p<0.05) and 1,25(OH)(2)D (95% vs. 58%, p<0.05). CONCLUSIONS: Vitamin D supplements had little to no impact on markers of bone turnover in term infants in the first few months of life, with the exception of osteocalcin. Ten weeks of cholecalciferol supplementation at a dose of 550 IU/day led to a marked increase of 25OHD concentration. The magnitude of 25OHD increment was inversely related to vitamin D status at baseline. Irrespective of the severity of vitamin D deficiency, a secondary hyperparathyroidism with elevated iPTH, ALP, phosphaturia or hypophosphatemia was not observed in the studied neonates.

[Pathologies of calcium-phosphate homeostasis]. / Patologie zwiazane z gospodarka wapniowo-fosforanowa.

The colossal progress in understanding of vitamin D and phosphate metabolism introduces new perspectives in chronic kidney disease (CKD) therapy. Increasing demand for phosphate excretion per nephron triggers the vicious cycle that leads to increase in FGF-23 and PTH and decrease in vitamin D and Klotho. Restriction of dietary phosphate intake (low phosphate diet) and administration of phosphate binder can be regarded as the most important interventions in this case. Because the vicious cycle is likely activated long before hyperphosphatemia occurs during CKD progression, phosphate restriction would have been more effective if started before serum phosphate levels increased, perhaps as soon as serum FGF-23 levels rose. Phosphate restriction alleviates phosphate overload per nephron and can disrupt the vicious cycle: phosphate restriction can reduce serum FGF-23 levels and increase vitamin D, which in turn increase Klotho expression in kidney and parathyroid glands. Inhibitors of rennin-angiotensin system (rosiglitazone, angiotensin-converting enzyme inhibitors) and proper vitamin D supplementation may also up-regulate Klotho expression. Increased Klotho in the kidney may improve FGF-23 sensitivity, which further reduce the amount of FGF-23 required for excreting a given amount of phosphate. Increased Klotho in parathyroid may improve the ability of FGF-23 to suppress PTH. Proper supplementation with vitamin D increase the concentration of substrate for local 1,25(OH)2D synthesis 25(OH)D, which directly suppress PTH, increase Klotho, and decrease FGF-23 by proanabolic action on bone. Improving vitamin D status by inhibition of CYP24A is also under evaluation, as well as antibodies against FGF-23, as modern therapies in CKD.

Vitamin D supplementation and status in infants: a prospective cohort observational study.

OBJECTIVE: Vitamin D status in infants depends on supplementation. We examined the vitamin D status in relation to supplementation dose and scheme in infants. PATIENTS AND METHODS: One hundred thirty-four infants age 6 months and 98 infants age 12 months (drop out 27%) were investigated. Vitamin D intake (diet, supplements), anthropometry, and 25-hydroxyvitamin D (25-OHD) serum concentration at the 6th and 12th months were assessed. RESULTS: Vitamin D intake of 1062 ± 694 IU at the 6th month was not different from that at the 12th month (937 ± 618 IU). Vitamin D intake expressed in international units per kilogram of body weight decreased from 141 ± 80 IU/kg at the 6th month to 93 ± 62 IU/kg at the 12th month (P < 0.0001), which was associated with a reduction in 25-OHD from 43 ± 20 ng/mL to 29 ± 12 ng/mL, respectively (P < 0.0001). In the subgroup of everyday supplemented infants (n = 43), vitamin D intake decreased from 143 ± 88 IU/kg at the 6th month to 118 ± 60 IU/kg at the 12th month (P < 0.05), which coincided with a reduction of 25-OHD from 40 ± 19 ng/mL to 32 ± 13 ng/mL (P < 0.01). In the subgroup with variable supplementation habits (n = 32), vitamin D intake decreased from 146 ± 79 IU/kg to 77 ± 56 IU/kg (P < 0.001), which was associated with a reduction of 25-OHD from 42 ± 21 ng/mL to 25 ± 8 ng/mL (P < 0.0001). 25-OHD concentration change between the 6th and the 12th months negatively correlated with the 25-OHD level assessed at the 6th month (r = -0.82; P < 0.0001). CONCLUSIONS: Vitamin D supplementation of infants should consider their rapid body weight increment. We postulate vitamin D daily dose close to 100 IU/kg body weight as favorable for infants up to age 12 months.

[Recommendations of prophylaxis of vitamin D deficiency in Poland (2009)]. / Zalecenia dotyczace profilaktyki niedoborów witaminy D w polsce (2009).

Adequate vitamin D intake and its status as well outdoor physical activity are important not only for normal bone development and Ca-P metabolism, but for optimal function of many organs and tissues throughout the body. Due to documented changes in dietary habits and physical activity level, both observed in growing children and adults, the prevalence of vitamin D insufficiency is continuously increasing. National Consultants and experts in this field established the Polish recommendations for prophylactic vitamin D supplementation in infants, toddlers, children and adolescents as well as in adults, including pregnant and lactating women based on current literature review. Taking into consideration pleyotropic vitamin D action and safety aspects serum 25-hydroxyvitamin D (25-OHD) level of 20-60 ng/ml (50-750 nmol/l) in children and 30-80 ng/ml (75-200 nmol/I) in adults is considered as optimal. Sunlight exposure inducing vitamin D production in the skin is main endogen source of vitamin D in the body but sunscreens may reduce skin synthesis by 90%. In Poland, skin synthesis is effective only from April to September so other sources of vitamin D such as diet and supplements play an important role. All newborns should be supplemented with 400 IU/d of vitamin D beginning from the first few days of life and continue during infancy. In formula fed infants vitamin D intake from the diet should be taken into account. In preterm infants higher total vitamin D intake (400-800 IU/day) is recommended till 40 weeks post conception. Total vitamin D intake in children and adolescents required from all sources (diet and/or supplements) should be 400 IU/d between October and March and throughout the whole year in case of inadequate vitamin D skin synthesis during the summer months. In overweight/obese children supplementation with higher dosage of vitamin D up to 800-1000 IU/d should be considered. Adults require 800-1000 IU/d of vitamin D. In pregnant and lactating women such supplementation is recommended in case of inadequate intake from diet and/or skin synthesis supplementation. Monitoring of serum 25-OHD level to define optimal dosage should be considered.

[Prophylaxis of vitamin D deficiency--Polish recommendations 2009]. / Polskie zalecenia dotyczace profilaktyki niedoborów witaminy D--2009.

Appropriate state procurement system for vitamin D is important not only for the proper functioning of the skeletal, maintaining calcium and phosphorus homeostasis, but also for a number of other organs and tissues in our body. In connection with the change in lifestyle including dietary habits change, the widespread use of UV filters and less outdoor activity, observed an increase in the percentage of vitamin D deficiency, both in population and developmental age and adults. Based on the results of recent scientific research team of experts provides recommendations for preventive Polish supply of vitamin D in infants, children, adolescents and adults, including pregnant women and nursing mothers.

[Prophylaxis of vitamin D deficiency--Polish recommendation 2009]. / Stanowisko Zespolu Ekspertów. Polskie zalecenia dotyczace profilaktyki niedoborów witaminy D - 2009.

Adequate vitamin D intake and its status are important not only for bone health and Ca-P metabolism, but for optimal function of many organs and tissues throughout the body. Due to documented changes in dietary habits and physical activity level, both observed in growing children and adults, the prevalence of vitamin D insufficiency is continuously increasing. Basing on current literature review and opinions of National Consultants and experts in the field, polish recommendations for prophylactic vitamin D supplementation in infants, toddlers, children and adolescents as well as in adults, including pregnant and lactating women have been established.