Vitamin D status in Poland

Abstract

functions of vitamin D seem to be higher (30-50 ng/ml; 75-125 nmol/l), 25 but still are considered uncertain. Some authors, however, argue that even for proper bone mineralization, levels higher than 30 ng/ml (75 nmol/l) are necessary. 26 Indisputably, low 25(OH)D levels (below 20 ng/ml) are common and were reported worldwide, 1-7 and this is a drawback because epidemiological data underlined an association between vitamin D deficit and a higher risk for chronic conditions and multimorbidity, including musculoskeletal disorders, cancer, autoimmune diseases, cardiovascular disease, diabetes, and infectious diseases. 1,3,[27][28][29][30] One of the countries with limited data on vitamin D status is Poland (49-54°N; Central Europe). Results of studies carried out in our country indicated that the problem of vitamin D deficiency considerably affects the Polish population. In a study of 448 adult residents of urban areas INTRODUCTION Vitamin D is an important prohormone that can be synthesized by the skin exposed to sunlight (UVB) or ingested with food. However, low outdoor activity, sun protection, and low vitamin D content of staple foods reduce the significance of sun and diet as natural sources for efficacy of vitamin D metabolism and related health effects. In consequence, evidence from various populations highlighted vitamin D deficiency as a public health problem with high prevalence.1-17 The prevalence of vitamin D deficiency depends on diagnostic thresholds defining vitamin D status that is determined by total serum 25(OH)D levels, 18 and the recommended levels of 25(OH)D are still an issue of debate.19-22 Currently, it is accepted that maintaining serum 25(OH) D at a level of 20 ng/ml (50 nmol/l) or above is beneficial at least for bone health and calcium homeostasis.23,24 Levels required for noncalcemic PATIENTS AND METHODSThis 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. RESULTSThe 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/m 2 , 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. CONCLUSIONSThe 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 f...

Vitamin D deficiency in urban Poland: what are the implications?

“…Thus, even if actual vitamin D deficiency was less common in their study population than indicated by Pludowski et al, 1 it is possible that substantial parts of the Polish population are vitamin D deficient or at high risk of deficiency.…”

“…2-4 Thus, unless ongoing randomized trials 5 provide evidence for reduced risks of major chronic diseases at much higher 25(OH)D levels, the prevalence estimates for 25(OH)D levels below 25 or 30 nmol/l (deficiency) and 50 nmol/l (suboptimal, at risk of deficiency) presented by Pludowski et al 1 should be appreciated as their main findings with respect to public health implications.…”

“…For the understanding of the results of Pludowski et al, 1 it is important to consider that a major fraction of circulating 25(OH)D derives from endogenous synthesis of its precursor vitamin D 3 in the human skin under ultraviolet B exposure. 6 The amount of ultraviolet B that reaches the earth's surface strongly depends on the zenith angle of the sun, which is why 25(OH)D undergoes substantial circannual fluctuations in populations residing at higher latitudes such as the Polish one.…”

“…1,4 In addition, it can be questioned whether such recommendations are practicable with respect to skin cancer prevention. 4 Attempts to improve vitamin D status through natural dietary sources alone do not appear promising, as fish is the only food that contains higher amounts of vitamin D. A fish-based diet may not suit the food preferences of parts of the Polish population, and recommendations to increase fish consumption have been criticized because of declining fish stocks.…”

Does combination of paricalcitol with cinacalcet in secondary hyperparathyroidism in hemodialysis treatment make sense?

“…Moreover, we did not study vitamin K levels reported to affect vascular calcifications in patients on hemodialysis 39 but not in nondialyzed patients. 40 As many healthy individuals 39 as well as dialyzed patients 41 are vitamin-D deficient, vitamin D should be supplemented first. As reported, correction of 25(OH)D deficiency in patients on hemodialysis was associated with better SHPT control with lower doses of vitamin D analogues.…”