Measurement of 25-OH-vitamin D in human serum using liquid chromatography tandem-mass spectrometry with comparison to radioimmunoassay and automated immunoassay

The plasma 25-OH vitamin D concentration is a reliable biomarker for vitamin D status but assay's variability makes adequate monitoring of vitamin D status difficult. We employed isotope-dilution liquid chromatography (LC) tandem-mass spectrometry (MS/MS) for the measurement of both 25-OH vitamin D₃ and 25-OH vitamin D₂ in human serum. Hexadeuterium labelled 25-OH vitamin D₃ internal standard (IS) was added to calibrators (prepared in phosphate-buffered saline with 60 g/L albumin), controls or patient sera and 25-OH vitamin D metabolites were released from vitamin D binding protein by adding sodium hydroxide prior to protein precipitation by acetonitrile/methanol (9:1, v/v). Subsequent off-line solid-phase extraction was followed by chromatographic separation on a C-18 column using a water/methanol/ammonium acetate gradient. Detection was by Atmospheric Pressure Electrospray Ionisation (AP-EI) followed by selected reaction monitoring. We compared the LC-MS/MS assay to the DiaSorin radioimmunoassay (RIA) and a recently re-standardised version of an automated electrochemiluminescent immunoassay (ECLIA) from Roche Diagnostics. We also analysed external quality control samples from the International Vitamin D External Quality Assessment Scheme (DEQAS) for comparison with other participating laboratories using LC-MS. The method was linear from 5 to at least 550 nmol/L with intra- and interday CV's ≤6% for both 25-OH vitamin D₃ and 25-OH vitamin D₂. Recoveries ranged between 94.9 and 106.9% for 25-OH vitamin D₃ and 82.7 and 100.3% for 25-OH vitamin D₂. Our results for the DEQAS serum pools averaged ?7.2% from the overall LC-MS method mean. The DiaSorin RIA agreed well with the LC-MS/MS method (r² = 0.90; average bias 1.61 nmol/L), the Roche ECLIA considerably disagreed (r² = 0.58; bias 10.13 nmol/L). This LC-MS/MS method is reliable and robust for the measurement of both 25-OH vitamin D₃ and 25-OH vitamin D₂ in human serum.     

PRegnancy Outcomes after a Maternity Intervention for Stressful EmotionS (PROMISES): study protocol for a randomised controlled trial

Background

There is ample evidence from observational prospective studies that maternal depression or anxiety during pregnancy is a risk factor for adverse psychosocial outcomes in the offspring. However, to date no previous study has demonstrated that treatment of depressive or anxious symptoms in pregnancy actually could prevent psychosocial problems in children. Preventing psychosocial problems in children will eventually bring down the huge public health burden of mental disease. The main objective of this study is to assess the effects of cognitive behavioural therapy in pregnant women with symptoms of anxiety or depression on the child's development as well as behavioural and emotional problems. In addition, we aim to study its effects on the child's development, maternal mental health, and neonatal outcomes, as well as the cost-effectiveness of cognitive behavioural therapy relative to usual care.

Methods/design

We will include 300 women with at least moderate levels of anxiety or depression at the end of the first trimester of pregnancy. By including 300 women we will be able to demonstrate effect sizes of 0.35 or over on the total problems scale of the child behavioural checklist 1.5-5 with alpha 5% and power (1-beta) 80%.Women in the intervention arm are offered 10-14 individual cognitive behavioural therapy sessions, 6-10 sessions during pregnancy and 4-8 sessions after delivery (once a week). Women in the control group receive care as usual.Primary outcome is behavioural/emotional problems at 1.5 years of age as assessed by the total problems scale of the child behaviour checklist 1.5 - 5 years.Secondary outcomes will be mental, psychomotor and behavioural development of the child at age 18 months according to the Bayley scales, maternal anxiety and depression during pregnancy and postpartum, and neonatal outcomes such as birth weight, gestational age and Apgar score, health care consumption and general health status (economic evaluation).

Trial Registration

Netherlands Trial Register (NTR): NTR2242

     

Focus: The Science of Stress: Can Maternal Prenatal Self-Reported and Physiological Distress Predict Postnatal Caregiving Practices?

Maternal prenatal distress is associated with child outcomes, including health, neurocognitive, and socio-emotional development. Knowledge on underlying mechanisms is limited, yet relevant for prevention and intervention. This study investigated whether maternal prenatal distress predicts specific caregiving practices that are known for their effects on child outcomes. Caregiving practices studied were maternal caregiving quality and the initiation and course of breastfeeding and room-sharing. We hypothesized that more maternal prenatal distress would be associated with altered caregiving practices. Participants were 174 healthy mother-child dyads. During the 37^th week of pregnancy maternal self-reported distress was assessed using questionnaires, and physiological stress by collecting saliva cortisol. Maternal caregiving quality was observed in postnatal week 5 during infant bathing. Weekly diaries on breastfeeding and daily diaries on room-sharing were completed during the first 6 postnatal months. In a regression analysis, no associations between maternal prenatal distress and caregiving quality were found. Multilevel analyses indicated that maternal prenatal evening cortisol was positively related to the initiation of breastfeeding and room-sharing. Replications are warranted, but these results suggest that breastfeeding and room-sharing initiation may be part of a mechanism underlying links between maternal prenatal physiological stress and child outcomes. As other prenatal cortisol markers and self-reported distress were not found to be related to the caregiving practices, it is likely that alternative mechanisms (co-)exist in explaining links between maternal prenatal distress and child outcomes. Future replication research including child outcomes and (other) potential mechanisms will inform prevention and intervention programs fostering healthy pregnancies and child development.     

Stressful Events and Continued Smoking and Continued Alcohol Consumption during Mid-Pregnancy

Aim

to examine whether the severity of different categories of stressful events is associated with continued smoking and alcohol consumption during mid-pregnancy. Also, we explored the explanation of these associations by anxiety and depressive symptoms during pregnancy. Finally, we studied whether the severity of stressful events was associated with the amount of cigarettes and alcohol used by continued users.

Method

we conducted a cross-sectional analysis using data from a population-based prospective cohort study. Pregnant women were recruited via midwifery practices throughout The Netherlands. We analyzed women who continued smoking (n = 113) or quit (n = 290), and women who continued alcohol consumption (n = 124) or quit (n = 1403) during pregnancy. Smoking, alcohol consumption, and perceived severity of stressful events were measured at 19 weeks of gestation. The State Trait Anxiety Inventory and the Edinburgh Postnatal Depression Scale were filled out at 14 weeks of gestation. Odds ratios were calculated as association measures and indicated the relative increase for the odds of continuation of smoking and alcohol consumption for the maximum severity score compared to the minimum score.

Findings

severity of the following stressful event categories was associated with continued alcohol consumption: ‘conflict with loved ones’ (OR = 10.4, p<0.01), ‘crime related’ (OR = 35.7, p<0.05), ‘pregnancy-specific’ (OR = 13.4, p<0.05), and the total including all events (OR = 17.2, p<0.05). Adjustment for potential confounders (age, parity and educational level) did not notably change the estimates. There was no association of anxiety and depressive symptoms with continued smoking or alcohol consumption. No associations emerged for continued smoking and severity of stressful events. The amount of cigarettes and alcohol consumption among continued users was not associated with severity of stressful events.

Conclusions

Our findings may be relevant for health care providers, in particular midwives and general practitioners. The impact of stressful events may be considered when advising pregnant women on smoking and alcohol consumption.