Many children with psychiatric disorders display somatic symptoms, although these are frequently overlooked. As somatic morbidity early in life negatively influences long-term outcomes, it is... Show moreMany children with psychiatric disorders display somatic symptoms, although these are frequently overlooked. As somatic morbidity early in life negatively influences long-term outcomes, it is relevant to assess comorbidity. However, studies of simultaneous psychiatric and somatic assessment in children are lacking. The aim of this study was to assess the prevalence of somatic comorbidities in a clinical sample of children and adolescents with psychiatric disorders in a naturalistic design. Data were assessed from 276 children with various psychiatric disorders (neurodevelopmental disorders, affective disorders, eating disorders and psychosis) aged 6-18 years. These data were collected as part of routine clinical assessment, including physical examination and retrospectively analyzed. For a subsample (n = 97), blood testing on vitamin D3, lipid spectrum, glucose and prolactin was available. Results of this cross-sectional study revealed that food intake problems (43%) and insomnia (66%) were common. On physical examination, 20% of the children were overweight, 12% displayed obesity and 38% had minor physical anomalies. Blood testing (n = 97) highlighted vitamin D3 deficiency (< 50 nmol/L) in 73% of the children. None of the predefined variables (gender, age, medication and socioeconomic factors) contributed significantly to the prevalence of somatic comorbidities. The main somatic comorbidities in this broad child- and adolescent psychiatric population consisted of (1) problems associated with food intake, including obesity and vitamin D3 deficiency and (2) sleeping problems, mainly insomnia. Child and adolescent psychiatrists need to be aware of potential somatic comorbidities and may promote a healthy lifestyle. Show less
BackgroundSuboptimal vitamin D status is common in people with celiac disease (CeD), a disease that can be characterized by the presence of serum anti-tissue transglutaminase antibodies (TG2A) (i.e... Show moreBackgroundSuboptimal vitamin D status is common in people with celiac disease (CeD), a disease that can be characterized by the presence of serum anti-tissue transglutaminase antibodies (TG2A) (i.e., TG2A positivity). To date, it remains unclear whether childhood TG2A positivity is associated with vitamin D status and how this potential association can be explained by other factors than malabsorption only, since vitamin D is mainly derived from exposure to sunlight. The aim of our study was therefore to assess whether childhood TG2A positivity is associated with vitamin D concentrations, and if so, to what extent this association can be explained by sociodemographic and lifestyle factors.MethodsThis cross-sectional study was embedded in the Generation R Study, a population-based prospective cohort. We measured serum anti-tissue transglutaminase antibodies (TG2A) concentrations and serum 25-hydroxyvitamin D (25(OH)D) concentrations of 3994 children (median age of 5.9 years). Children with serum TG2A concentrations >= 7 U/mL were considered TG2A positive. To examine associations between TG2A positivity and 25(OH)D concentrations, we performed multivariable linear regression, adjusted for sociodemographic and lifestyle factors.ResultsVitamin D deficiency (serum 25(OH)D < 50 nmol/L) was found in 17 out of 54 TG2A positive children (31.5%), as compared to 1182 out of 3940 TG2A negative children (30.0%). Furthermore, TG2A positivity was not associated with 25(OH)D concentrations (beta -2.20; 95% CI -9.72;5.33 for TG2A positive vs. TG2A negative children), and this did not change after adjustment for confounders (beta -1.73, 95% CI -8.31;4.85).ConclusionsOur findings suggest there is no association between TG2A positivity and suboptimal vitamin D status in the general pediatric population. However, the overall prevalence of vitamin D deficiency in both populations was high, suggesting that screening for vitamin D deficiency among children, regardless of TG2A positivity, would be beneficial to ensure early dietary intervention if needed. Show less
Vitamin D is essential for bone health. Vitamin D deficiency causes rickets and osteomalacia. In non-Western immigrants in the Netherlands, low vitamin D status is common. For example, low... Show moreVitamin D is essential for bone health. Vitamin D deficiency causes rickets and osteomalacia. In non-Western immigrants in the Netherlands, low vitamin D status is common. For example, low concentrations of 25-hydroxyvitamin D have been reported among Turkish, Moroccan, Surinamese, and sub-Saharan African populations. However, little is known about the vitamin D status of Chinese in the Netherlands. Therefore, this thesis aimed to determine the vitamin D status of a Chinese population in the Netherlands, and examined determinants of low 25-hydroxyvitamin D concentrations. Also, associations between 25-hydroxyvitamin D and bone, cardio-metabolic outcomes, and genetic factors were examined. Finally, a patient-friendly method to assess 25-hydroxyvitamin D concentration was investigated. The main result was that serum 25-hydroxyvitamin D concentration of our study population (42-46 nmol/L) appeared to be lower than that of ethnic Dutch (60-67 nmol/L), but better than other non-Western immigrant groups in the Netherlands (24-38 nmol/L), as previously found by others. Almost one-quarter of our study population, however, did not meet the requirement for an adequate vitamin D status of the Health Council of the Netherlands (Gezondheidsraad). Therefore, public health authorities and health care providers should continue to make efforts to improve the vitamin D status of non-Western immigrants. Show less
Mechanical stress determines bone mass and structure. It is not known whether mechanical loading affects expression of bone regulatory genes in a combined deficiency of estrogen and vitamin D. We... Show moreMechanical stress determines bone mass and structure. It is not known whether mechanical loading affects expression of bone regulatory genes in a combined deficiency of estrogen and vitamin D. We studied the effect of mechanical loading on the messenger RNA (mRNA) expression of bone regulatory genes during vitamin D and/or estrogen deficiency. We performed a single bout in vivo axial loading with 14 N peak load, 2 Hz frequency and 360 cycles in right ulnae of nineteen weeks old female control Wistar rats with or without ovariectomy (OVX), vitamin D deficiency and the combination of OVX and vitamin D deficiency (N = 10/group). Total bone RNA was isolated 6 hours after loading, and mRNA expression was detected ofMepe, Fgf23, Dmp1, Phex, Sost, Col1a1, Cyp27b1, Vdr, andEsr1. Serum levels of 25(OH)D, 1,25(OH)(2)D and estradiol were also measured at this time point. The effect of loading, vitamin D and estrogen deficiency and their interaction on bone gene expression was tested using a mixed effect model analysis. Mechanical loading significantly increased the mRNA expression ofMepe, andSost, whereas it decreased the mRNA expression ofFgf23andEsr1. Mechanical loading showed a significant interaction with vitamin D deficiency with regard to mRNA expression ofVdrandEsr1. Mechanical loading affected gene expression ofMepe, Fgf23, Sost, andEsr1independently of vitamin D or estrogen, indicating that mechanical loading may affect bone turnover even during vitamin D deficiency and after menopause. Show less
Vitamin D deficiency is generally associated with the consequences of the Industrial Revolution, such as tall densely-packed buildings and air pollution blocking sunlight. Dermal synthesis of... Show moreVitamin D deficiency is generally associated with the consequences of the Industrial Revolution, such as tall densely-packed buildings and air pollution blocking sunlight. Dermal synthesis of vitamin D under the influence of UVB radiation is important for a healthy skeleton and a deficiency may lead to pathological bowing of bones. The Netherlands did not experience the Industrial Revolution as many other European countries did and vitamin D deficiency was expected to be (nearly) absent in Dutch communities. To test this, six 17th - 19th century human skeletal collections from rural and small urban centres were analysed for vitamin D deficiency (N = 632 individuals). Regardless of geographic location, community size, daily activities, and socioeconomic status, all evaluated communities experienced vitamin D deficiency in childhood. Sociocultural practices, such as gender-related activities, as opposed to classic factors, are suggested to have been main etiological agents in the development of vitamin D deficiency. Application of newly developed methods for identification of this disease in teeth, showed vitamin D deficiency to be recurrent and often seasonal. This study stresses the importance of investigating vitamin D deficiency in every community to better understand the deteriorating effect that sociocultural practices may have had on health. Show less
The most common cause of vitamin D deficiency is inadequate dermal exposure to sunlight. Residual rickets is nonadult vitamin D deficiency still evident in an adult individual, whereas osteomalacia... Show moreThe most common cause of vitamin D deficiency is inadequate dermal exposure to sunlight. Residual rickets is nonadult vitamin D deficiency still evident in an adult individual, whereas osteomalacia occurs in adulthood. Previous research on the Beemster population, a 19th century rural community in the Netherlands, identified rickets in 30.4% of the nonadults between the ages of two and four years (n =7/23). Because the sex of these nonadults was not known it was not possible to determine if there were differences between boys and girls. To overcome this gap in our knowledge, the aim of this paper is to determine if there are gender related differences in vitamin D deficiency in the Beemster skeletal collection, based on adults with residual rickets and osteomalacia. Out of 200 adults (100 females; 100 males) no cases of osteomalacia were detected. However, there were 29 cases of residual rickets (14.5%), with 21 of those cases in females (21.0%; 21/100). A complex interplay of multiple factors is proposed to have affected vitamin D levels in nonadults, including sociocultural variables such as gender-based labour norms. This research highlights the importance of continuing to explore gender-based health differences in past populations. Show less
