Implications of standardization of serum 25-hydroxyvitamin D data for the evaluation of vitamin D status in Germany, including a temporal analysis.

BACKGROUND: Comparability of 25-hydroxyvitamin D (25(OH)D) measurements is hampered by method-related differences in measurement values. International standardization of laboratory assays has been suggested to solve this problem. METHODS: As part of the European Commission-funded project 'Food-based solutions for optimal vitamin D nutrition and health through the life cycle' (ODIN), original measurements of serum 25(OH)D of three German national health surveys conducted between 1998 and 2011 have been standardized retrospectively. In these representative population-based samples including persons aged between 1 and 79 years, the original 25(OH)D values were compared with those after standardization. Mean values and prevalences of vitamin D deficiency, insufficiency, and sufficiency (25(OH)D levels < 30, 30- < 50, and > =50 nmol/l, respectively) were calculated by sex and age groups based on original and standardized 25(OH)D data. RESULTS: In comparison to the original 25(OH)D levels, the standardized levels showed higher means overall and in age- and sex-specific analyses. After standardization, the prevalence of vitamin D deficiency was lower in all surveys while the prevalence of vitamin D sufficiency was higher. Nevertheless, even after standardization ~ 15% of adults and 12.5% of children had serum 25(OH)D levels < 30 nmol/l. Thus, the proportion of deficient vitamin D levels in the German population is still considerable. CONCLUSIONS: The use of standardization of 25(OH)D levels has a substantial impact on estimates of the vitamin D status in Germany. Since clinical diagnostic, therapeutic and public health decision-making require valid and comparable data, standardization and calibration of commercial, clinical and research laboratory assays for 25(OH)D measurement should become common practice. Until then, researchers, health practitioners and policy makers should be aware of the peculiarities of the measurement methods when comparing and interpreting 25(OH)D levels.

Consumption of sugary soft drinks among children and adolescents in Germany. Results of the cross-sectional KiGGS Wave 2 study and trends.

Consuming large amounts of sugary beverages has been related to developing obesity, diabetes mellitus type II and other chronic diseases. KiGGS Wave 2 (2014-2017) provides data on the consumption of sugary soft drinks in the 3-17 year age group in Germany. Overall, 13.7% of girls and 17.6% of boys consume one to three times a day sugary soft drinks and 3.3% of girls and 4.7% of boys four or more times. Consumption frequency increases with age and is higher among children and adolescents with low socioeconomic status (SES) than for those of the same age with high SES. The share of adolescents who drink sugary soft drinks daily has decreased since the KiGGS baseline study (2003-2006).

Baseline Assessment of 25-Hydroxyvitamin D Reference Material and Proficiency Testing/External Quality Assurance Material Commutability: A Vitamin D Standardization Program Study.

The Vitamin D Standardization Program (VDSP) coordinated a study in 2012 to assess the commutability of reference materials and proficiency testing/external quality assurance materials for total 25-hydroxyvitamin D [25(OH)D] in human serum, the primary indicator of vitamin D status. A set of 50 single-donor serum samples as well as 17 reference and proficiency testing/external quality assessment materials were analyzed by participating laboratories that used either immunoassay or LC-MS methods for total 25(OH)D. The commutability test materials included National Institute of Standards and Technology Standard Reference Material 972a Vitamin D Metabolites in Human Serum as well as materials from the College of American Pathologists and the Vitamin D External Quality Assessment Scheme. Study protocols and data analysis procedures were in accordance with Clinical and Laboratory Standards Institute guidelines. The majority of the test materials were found to be commutable with the methods used in this commutability study. These results provide guidance for laboratories needing to choose appropriate reference materials and select proficiency or external quality assessment programs and will serve as a foundation for additional VDSP studies.

Baseline Assessment of 25-Hydroxyvitamin D Assay Performance: A Vitamin D Standardization Program (VDSP) Interlaboratory Comparison Study.

The Vitamin D Standardization Program (VDSP) coordinated an interlaboratory study to assess the comparability of measurements of total 25-hydroxyvitamin D [25(OH)D] in human serum, which is the primary marker of vitamin D status. A set of 50 individual donor samples were analyzed by 15 different laboratories representing national nutrition surveys, assay manufacturers, and clinical and/or research laboratories to provide results for total 25(OH)D using both immunoassays (IAs) and LC tandem MS (MS/MS). The results were evaluated relative to bias compared with the target values assigned based on a combination of measurements at Ghent University (Belgium) and the U.S. National Institute of Standards and Technology using reference measurement procedures for the determination of 25(OH)D2 and 25(OH)D3. CV and mean bias for each laboratory and assay platform were assessed and compared with previously established VDSP performance criteria, namely CV ≤ 10% and mean bias ≤ 5%. Nearly all LC-MS/MS results achieved VDSP criteria, whereas only 50% of IAs met the criterion for a ≤10% CV and only three of eight IAs achieved the ≤5% bias. These results establish a benchmark for the evaluation of 25(OH)D assay performance and standardization activities in the future.

Association between vitamin D and depressive symptoms varies by season: Results from the German Health Interview and Examination Survey for Adults (DEGS1).

BACKGROUND: Findings from epidemiological studies regarding seasonal variations in the association between vitamin D status and depression are inconsistent. METHODS: Cross-sectional analysis of data from 6331 participants aged 18-79 years in the nationwide representative German Health Interview and Examination Survey for Adults 2008-2011 (DEGS1). Associations between 25-hydroxy-vitamin-D (25(OH)D) serum levels in quartiles and current depressive symptoms as measured by the Patient Health Questionnaire depression module (PHQ-9) and defined as severity of depressive symptoms (PHQ-9 score, range 0-27 points) and elevated depressive symptoms (PHQ-9 score ≥10 points) were analysed using multivariable linear and logistic regression adjusted for sociodemographic, biological and lifestyle factors. Analyses were stratified by summertime (May to October) and wintertime (November to April) because of evidence for interaction with season (p≤0.01). RESULTS: In crude analyses, vitamin D status was inversely associated with both depression outcomes in summertime but not in wintertime. After adjustment for potential confounders, a significant association with severity of depressive symptoms remained in summer, with 0.73 point lower PHQ-9 scores in the highest versus lowest quartile. The association between 25(OH)D quartiles and elevated depressive symptoms in summertime was less strong and no longer significant in fully adjusted models. LIMITATIONS: Participants with severe depression may be underrepresented in DEGS1. Residual confounding cannot be excluded. CONCLUSION: 25(OH)D serum levels were inversely associated with current depressive symptoms in summer but not in wintertime. The fact that the association is stronger in summertime suggests that vitamin D deficiency may be a consequence rather than a cause of depression.

Vitamin D deficiency in Europe: pandemic?

BACKGROUND: Vitamin D deficiency has been described as being pandemic, but serum 25-hydroxyvitamin D [25(OH)D] distribution data for the European Union are of very variable quality. The NIH-led international Vitamin D Standardization Program (VDSP) has developed protocols for standardizing existing 25(OH)D values from national health/nutrition surveys. OBJECTIVE: This study applied VDSP protocols to serum 25(OH)D data from representative childhood/teenage and adult/older adult European populations, representing a sizable geographical footprint, to better quantify the prevalence of vitamin D deficiency in Europe. DESIGN: The VDSP protocols were applied in 14 population studies [reanalysis of subsets of serum 25(OH)D in 11 studies and complete analysis of all samples from 3 studies that had not previously measured it] by using certified liquid chromatography-tandem mass spectrometry on biobanked sera. These data were combined with standardized serum 25(OH)D data from 4 previously standardized studies (for a total n= 55,844). Prevalence estimates of vitamin D deficiency [using various serum 25(OH)D thresholds] were generated on the basis of standardized 25(OH)D data. RESULTS: An overall pooled estimate, irrespective of age group, ethnic mix, and latitude of study populations, showed that 13.0% of the 55,844 European individuals had serum 25(OH)D concentrations <30 nmol/L on average in the year, with 17.7% and 8.3% in those sampled during the extended winter (October-March) and summer (April-November) periods, respectively. According to an alternate suggested definition of vitamin D deficiency (<50 nmol/L), the prevalence was 40.4%. Dark-skinned ethnic subgroups had much higher (3- to 71-fold) prevalence of serum 25(OH)D <30 nmol/L than did white populations. CONCLUSIONS: Vitamin D deficiency is evident throughout the European population at prevalence rates that are concerning and that require action from a public health perspective. What direction these strategies take will depend on European policy but should aim to ensure vitamin D intakes that are protective against vitamin D deficiency in the majority of the European population.

Vitamin D status of adults in Germany.

Vitamin D plays an important role in the body as part of bone metabolism. Blood serum concentrations demonstrate that 30.2% of adults (29.7% of women and 30.8% of men) have a deficient vitamin D status. In total, 38.4% of adults (38.6% of women, 38.3% of men) have an adequate status. Although there is little variation among men between the various age groups, the proportion of women with deficient vitamin D status increases with age, while the proportion of women with an adequate status decreases. Furthermore, adults with a low socio-economic status are significantly more likely to have a deficient vitamin D status than adults with a higher socio-economic status. Vitamin D status is subject to strong seasonal fluctuations. In order to ensure adequate concentrations of serum vitamin D, it is recommended to expose the face, hands and arms to the sun two to three times a week between March and October without using sun protection; however, sunburn should be strictly avoided.

Cases of alcohol poisoning involving in-patient treatment.

Alcohol poisonings represent the direct consequences of excess alcohol consumption. In 2014, in Germany 115,967 persons aged 10 to 79 years were treated as in-patients with the diagnosis "acute alcohol intoxication". In almost all age groups, male persons are affected significantly more frequently than female persons. In the past 14 years, the number of alcohol poisonings involving in-patient treatment amongst children, adolescents and adults has more than doubled. The need to prevent excessive alcohol consumption remains a key objective. Preventive measures should begin while children are still at an early age and in adolescence.

Alcohol-related mortality among adults.

Risky, abusive and addictive consumption of alcoholic beverages greatly jeopardizes the drinker's health; it can harm third parties, affects the drinker's social relations and causes considerable costs to the national economy. National and international campaigns therefore aim to lower alcohol consumption and its consequences. Alcohol-related mortality is the most serious outcome of excessive alcohol consumption. Official statistics on causes of death include a number of entirely alcohol-related diagnoses. In 2014 an examination of deceased adults in Germany revealed a directly alcohol-related cause of death in 14,095 cases (20.8 for every 100,000 inhabitants). Such diagnoses were considerably more frequent for men than women, reaching a peak in the 55 to 64 age group. Overall, death from alcohol abuse is declining in Germany. Because by international standards there is still a relatively high consumption of alcoholic beverages in Germany, more action needs to be taken.

Traffic accidents under the influence of alcohol.

In 2014, 260 persons were killed in Germany in road traffic accidents under the influence of alcohol. Compared to road traffic accidents in general, accidents under the influence of alcohol frequently have particularly serious consequences. In 2014, police established that 13,742 persons were involved in traffic accidents while under the influence of alcohol. Just under 40% of these were young men aged 18 to 34 years. The number of road traffic accidents under the influence of alcohol has been declining for over 20 years now and in 2014 reached its lowest level since the recording of the relevant data began.

Vitamin D status among adults in Germany--results from the German Health Interview and Examination Survey for Adults (DEGS1).

BACKGROUND: In 1998, more than half of the adult population in Germany had serum 25-hydroxy-vitamin-D [25(OH)D] levels below the common threshold of 50 nmol/l. Since then, there has been a lot of attention for vitamin D in the scientific community, the media and the general population and serum 25(OH)D levels may have increased as a consequence. With data from the 'German Health Interview and Examination Survey for Adults' (DEGS1) the current situation of vitamin D status can be analysed. METHODS: DEGS1, a national health survey among adults in Germany conducted by the Robert Koch Institute between 2008 and 2011, included 6,995 persons with available serum 25(OH)D levels. We calculated the proportion of participants with serum 25(OH)D levels <30 nmol/l, 30- < 50 nmol/l and > =50 nmol/l overall and according to age, season and latitude of residence as well as percentiles of serum 25(OH)D according to month of examination. Determinants of vitamin D status were analysed with multiple linear regression models. RESULTS: Mean serum 25(OH)D level was 45.6 nmol/l with no significant sex differences (p = 0.47). 61.6% of the participants had serum 25(OH)D levels <50 nmol/l, 30.2% had levels <30 nmol/l. During summer, half of the participants had levels > =50 nmol/l, during winter time, 25% of the participants had levels <30 nmol/l. A significant latitudinal gradient was observed in autumn for men and in winter for women. In multiple linear regression analyses, examination during winter time, residing in northern latitude, non-use of vitamin D supplements, low sport activity, high Body Mass Index (BMI) and high media consumption were independently and significantly associated with lower serum 25(OH)D levels in both sexes. In addition, among women, significant associations with lower 25(OH)D levels were observed for older age and lower socio-economic status, among men, for low vitamin D intake and more residential traffic. CONCLUSIONS: Serum 25(OH)D levels below the threshold of 50 nmol/l are still common among adults in Germany, especially during winter and spring and in higher latitudes. Potentially modifiable factors of poorer vitamin D status are higher BMI, lack of sport activity and high media use.