Effect of Monthly High-Dose Vitamin D Supplementation on Acute Respiratory Infections in Older Adults: A Randomized Controlled Trial

BACKGROUND

Although adults with low vitamin D status are at increased risk of acute respiratory infection (ARI), randomized controlled trials of vitamin D supplementation have provided inconsistent results.

METHODS

We performed a randomized, double-blinded, placebo-controlled trial of 5110 adults aged 50-84 years. In 2011-2012, participants were randomized to an initial oral dose of 200 000 IU vitamin D3 followed by 100 000 IU monthly (n = 2558) or placebo (n = 2552) until late 2013 (median follow-up, 1.6 years). Participants reported upper and lower ARIs on monthly questionnaires. Cox models analyzed time to first ARI (upper or lower) by treatment group.

RESULTS

Participants' mean age was 66 years and 58% were male; 83% were of European/other ethnicity, with the rest Maori, Polynesian, or South Asian. Mean (SD) baseline blood 25-hydroxyvitamin D [25(OH)D] level was 63 (24) nmol/L; 25% were <50 nmol/L. In a random sample (n = 441), vitamin D supplementation increased mean 25(OH)D to 135 nmol/L at 3 years, while those on placebo remained at 63 nmol/L. During follow-up, 3737 participants reported ≥1 ARI: 74.1% in the vitamin D group versus 73.7% in the placebo group. The hazard ratio for vitamin D compared with placebo was 1.01 (95% CI, 0.94, 1.07). Similar results were seen in most subgroups, including those with baseline 25(OH)D <50 nmol/L and in analyses of the upper/lower components of the ARI outcome.

CONCLUSIONS

Monthly high-dose vitamin D supplementation does not prevent ARI in older adults with a low prevalence of profound vitamin D deficiency at baseline. Whether effects of daily or weekly dosing differ requires further study.

CLINICAL TRIALS REGISTRATION

Australian New Zealand Clinical Trials Registry, identifier ACTRN12611000402943.

Effect of Monthly High-Dose Vitamin D Supplementation on Cardiovascular Disease in the Vitamin D Assessment Study : A Randomized Clinical Trial

Importance

Cohort studies have reported increased incidence of cardiovascular disease (CVD) among individuals with low vitamin D status. To date, randomized clinical trials of vitamin D supplementation have not found an effect, possibly because of using too low a dose of vitamin D.

Objective

To examine whether monthly high-dose vitamin D supplementation prevents CVD in the general population.

Design, Setting, and Participants

The Vitamin D Assessment Study is a randomized, double-blind, placebo-controlled trial that recruited participants mostly from family practices in Auckland, New Zealand, from April 5, 2011, through November 6, 2012, with follow-up until July 2015. Participants were community-resident adults aged 50 to 84 years. Of 47 905 adults invited from family practices and 163 from community groups, 5110 participants were randomized to receive vitamin D3 (n = 2558) or placebo (n = 2552). Two participants retracted consent, and all others (n = 5108) were included in the primary analysis.

Interventions

Oral vitamin D3 in an initial dose of 200 000 IU, followed a month later by monthly doses of 100 000 IU, or placebo for a median of 3.3 years (range, 2.5-4.2 years).

Main Outcomes and Measures

The primary outcome was the number of participants with incident CVD and death, including a prespecified subgroup analysis in participants with vitamin D deficiency (baseline deseasonalized 25-hydroxyvitamin D [25(OH)D] levels <20 ng/mL). Secondary outcomes were myocardial infarction, angina, heart failure, hypertension, arrhythmias, arteriosclerosis, stroke, and venous thrombosis.

Results

Of the 5108 participants included in the analysis, the mean (SD) age was 65.9 (8.3) years, 2969 (58.1%) were male, and 4253 (83.3%) were of European or other ethnicity, with the remainder being Polynesian or South Asian. Mean (SD) baseline deseasonalized 25(OH)D concentration was 26.5 (9.0) ng/mL, with 1270 participants (24.9%) being vitamin D deficient. In a random sample of 438 participants, the mean follow-up 25(OH)D level was greater than 20 ng/mL higher in the vitamin D group than in the placebo group. The primary outcome of CVD occurred in 303 participants (11.8%) in the vitamin D group and 293 participants (11.5%) in the placebo group, yielding an adjusted hazard ratio of 1.02 (95% CI, 0.87-1.20). Similar results were seen for participants with baseline vitamin D deficiency and for secondary outcomes.

Conclusions and Relevance

Monthly high-dose vitamin D supplementation does not prevent CVD. This result does not support the use of monthly vitamin D supplementation for this purpose. The effects of daily or weekly dosing require further study.

Trial Registration

clinicaltrials.gov Identifier: ACTRN12611000402943.

Smoking in pregnancy is a key factor for sudden infant death among Māori

AIM

To examine the sudden unexpected death in infancy (SUDI) disparity between Māori and non-Māori in New Zealand.

METHODS

A nationwide prospective case-control study ran from March 2012 to February 2015. Exposure to established SUDI risk factors was analysed to investigate the disparity experienced by Māori. Infant ethnicity was based on mother's ethnicity. Māori ethnicity was prioritised. Non-Māori includes Pacific, Asian, NZ European and Other.

RESULTS

There were 137 cases and 649 controls. The Māori SUDI rate was 1.41/1000 live births compared to 0.53/1000 for non-Māori. Parents/caregivers of 132 cases (96%) and 258 controls (40%) were interviewed. Smoking in pregnancy was associated with an equally increased SUDI risk for Māori (adjusted OR = 8.11, 95% CI = 2.64, 24.93) and non-Māori (aOR = 5.09, 95% CI = 1.79, 14.47), as was bed-sharing (aOR = 3.66, 95% CI = 1.49, 9.00 vs aOR = 11.20, 95% CI = 3.46, 36.29). Bed-sharing prevalence was similar; however, more Māori controls smoked during pregnancy (46.7%) than non-Māori (22.8%). The main contributor relating to increased SUDI risk for Māori/non-Māori infants is the combination of smoking in pregnancy and bed sharing.

CONCLUSION

The association between known SUDI risk factors, including bed sharing and/or smoking in pregnancy and SUDI risk, is the same regardless of ethnicity. Māori infants are exposed more frequently to both behaviours because of the higher Māori smoking rate.

Factors associated with body mass index in children and adolescents: An international cross-sectional study

BACKGROUND

The increasing prevalence of overweight and obesity in childhood has implications for their future health. There are many potential contributors to overweight and obesity in childhood. The aim was to investigate the association between postulated risk factors and body mass index (BMI) in children and adolescents.

METHODS

Secondary analysis of data from a multi-centre, multi-country, cross-sectional study (ISAAC Phase Three). Parents/guardians of children aged 6-7 years completed a questionnaire about their child's current height and weight, and the postulated risk factors. Adolescents aged 13-14 years reported their own height and weight and answered questions about the postulated risk factors. A general linear mixed model was used to determine the association between BMI and the postulated risk factors. Imputation was used if there were missing responses for 3 or fewer explanatory variables.

RESULTS

65,721 children (27 centres, 15 countries) and 189,282 adolescents (70 centres, 35 countries) were included in the final analyses. Many statistically significant associations were identified, although for most variables the effect sizes were small. In children birth weight (for each kg increase in birth weight the BMI increased by +0.43 kg/m2, p<0.001), television viewing (5+ hours/day +0.33 kg/m2 vs. <1 hour/day, p<0.001), fast food (≥3 times/week +0.16 kg/m2 vs. never, p<0.001) vigorous physical activity (3+ hours/week 0.071 kg/m2 vs. never, p = 0.023) and maternal smoking in the first year of life (+0.13 kg/m2, p<0.001) were associated with a higher BMI in the adjusted model. Nut consumption (≥3 times/week -0.11 kg/m2 vs. never, p = 0.002) was associated with a lower BMI. Early life exposures (antibiotics, paracetamol and breast feeding) were also associated with BMI. For adolescents statistically significant associations with BMI and were seen with maternal smoking (+0.25 kg/m2, p<0.001), television viewing (5+ hours/day +0.23 kg/m2 vs. <1 hour/day, p<0.001), fast food (≥3 times/week -0.19 kg/m2 vs. never, p<0.001), vigorous physical activity (3+ hours/week 0.047 kg/m2 vs. never, p<0.001) and nuts (≥3 times/week -0.22 kg/m2 vs. never, p<0.001).

CONCLUSIONS

Although several early life exposures were associated with small differences in BMI, most effect sizes were small. Larger effect sizes were seen with current maternal smoking, television viewing (both with higher BMI) and frequent nut consumption (lower BMI) in both children and adolescents, suggesting that current behaviours are more important than early exposures. Although many variables may influence BMI in childhood, the putative factors studied are not of sufficient magnitude to support major public health interventions.

Association between Frequency of Consumption of Fruit, Vegetables, Nuts and Pulses and BMI: Analyses of the International Study of Asthma and Allergies in Childhood (ISAAC)

Diets which emphasize intakes of plant-based foods are recommended to reduce disease risk and for promoting healthy weight. The aim of this study was to examine the association between fruit, vegetables, pulses and nut intake and body mass index (BMI) across countries in adolescents (13–14 years) and children (6–7 years). Data from the International Study of Asthma and Allergies in Childhood; 77,243 children’s parents and 201,871 adolescents was used to examine the association between dietary intake (Food Frequency Questionnaire) and BMI using general linear models, adjusting for country gross national index. Adolescents who consumed fruit, vegetables, pulses and nuts three or more times a week had a lower BMI than the never or occasional group; eating nuts three or more times a week, was associated with a BMI value of 0.274 kg/m² lower than the never group (p < 0.001). Compared to children who never or occasionally reported eating vegetables, those reporting that they ate vegetables three or more times per week had a lower BMI of −0.079 kg/m². In this large global study, an inverse association was observed between BMI and the reported increasing intake of vegetables in 6–7 years old and fruit, vegetables, pulses and nuts in adolescents. This study supports current dietary recommendations which emphasize the consumption of vegetables, nut and pulses, although the effect sizes were small.

Effect of monthly high-dose vitamin D on bone density in community-dwelling older adults substudy of a randomized controlled trial

BACKGROUND

Severe vitamin D deficiency causes osteomalacia, yet trials of vitamin D supplementation in the community have not on average demonstrated benefit to bone mineral density (BMD) or fracture risk in adults.

OBJECTIVE

To determine whether monthly high-dose vitamin D supplementation influences BMD in the general population and in those with low 25-hydroxyvitamin D levels.

METHODS

Two-year substudy of a trial in older community-resident adults. A total of 452 participants were randomized to receive monthly doses of vitamin D3 100 000 IU, or placebo. The primary end-point was change in lumbar spine BMD. Exploratory analyses to identify thresholds of baseline 25-hydroxyvitamin D for vitamin D effects on BMD were prespecified.

RESULTS

Intention-to-treat analyses showed no significant treatment effect in the lumbar spine (between-groups difference 0.0071 g cm^-2 , 95%CI: -0.0012, 0.0154) or total body but BMD loss at both hip sites was significantly attenuated by ~1/2% over 2 years. There was a significant interaction between baseline 25-hydroxyvitamin D and treatment effect (P = 0.04). With baseline 25-hydroxyvitamin D ≤ 30 nmol L^-1 (n = 46), there were between-groups BMD changes at the spine and femoral sites of ~2%, significant in the spine and femoral neck, but there was no effect on total body BMD. When baseline 25-hydroxyvitamin D was >30 nmol L^-1 , differences were ~1/2% and significant only at the total hip.

CONCLUSIONS

This substudy finds no clinically important benefit to BMD from untargeted vitamin D supplementation of older, community-dwelling adults. Exploratory analyses suggest meaningful benefit in those with baseline 25-hydroxyvitamin D ≤ 30 nmol L^-1 . This represents a significant step towards a trial-based definition of vitamin D deficiency for bone health in older adults.

Effect of Monthly, High-Dose, Long-Term Vitamin D Supplementation on Central Blood Pressure Parameters: A Randomized Controlled Trial Substudy

BACKGROUND

The effects of monthly, high-dose, long-term (≥1-year) vitamin D supplementation on central blood pressure (BP) parameters are unknown.

METHODS AND RESULTS

A total of 517 adults (58% male, aged 50-84 years) were recruited into a double-blinded, placebo-controlled trial substudy and randomized to receive, for 1.1 years (median; range: 0.9-1.5 years), either (1) vitamin D3 200 000 IU (initial dose) followed 1 month later by monthly 100 000-IU doses (n=256) or (2) placebo monthly (n=261). At baseline (n=517) and follow-up (n=380), suprasystolic oscillometry was undertaken, yielding aortic BP waveforms and hemodynamic parameters. Mean deseasonalized 25-hydroxyvitamin D increased from 66 nmol/L (SD: 24) at baseline to 122 nmol/L (SD: 42) at follow-up in the vitamin D group, with no change in the placebo group. Despite small, nonsignificant changes in hemodynamic parameters in the total sample (primary outcome), we observed consistently favorable changes among the 150 participants with vitamin D deficiency (<50 nmol/L) at baseline. In this subgroup, mean changes in the vitamin D group (n=71) versus placebo group (n=79) were -5.3 mm Hg (95% confidence interval [CI], -11.8 to 1.3) for brachial systolic BP (P=0.11), -2.8 mm Hg (95% CI, -6.2 to 0.7) for brachial diastolic BP (P=0.12), -7.5 mm Hg (95% CI, -14.4 to -0.6) for aortic systolic BP (P=0.03), -5.7 mm Hg (95% CI, -10.8 to -0.6) for augmentation index (P=0.03), -0.3 m/s (95% CI, -0.6 to -0.1) for pulse wave velocity (P=0.02), -8.6 mm Hg (95% CI, -15.4 to -1.9) for peak reservoir pressure (P=0.01), and -3.6 mm Hg (95% CI, -6.3 to -0.8) for backward pressure amplitude (P=0.01).

CONCLUSIONS

Monthly, high-dose, 1-year vitamin D supplementation lowered central BP parameters among adults with vitamin D deficiency but not in the total sample.

CLINICAL TRIAL REGISTRATION

URL: http://www.anzctr.org.au. Unique identifier: ACTRN12611000402943.

Sun exposure and 25-hydroxyvitamin D3 levels in a community sample: Quantifying the association with electronic dosimeters

There is uncertainty about the amount of sun exposure required to increase low blood 25-hydroxyvitamin D (25(OH)D₃) levels, a possible disease risk factor. The study aimed to quantify the association between sun exposure and serum 25(OH)D₃ concentrations in a multiethnic community sample (n=502) living in Auckland (37°S) and Dunedin (46°S), New Zealand, aged 18-85 years. They wore electronic ultraviolet dosimeters between March and November (autumn, winter and spring) for 8 weeks to record their sun exposure. This was converted to standard erythemal doses (SEDs), corrected for clothing to generate equivalent full-body exposures, SED_EFB. Blood samples were collected at the end of weeks 4 and 8 to measure 25(OH)D₃. Median weekly SED_EFB was 0.33 during weeks 1-4 and 0.34 during weeks 5-8. Weekly exposures <0.5 SED_EFB during weeks 5-8 were associated with decreasing 25(OH)D₃ concentrations at the end of week 8. There was a non-linear association between sun exposure and 25(OH)D₃, with most of the increase in 25(OH)D₃ being at exposures <2 SED_EFB per week. This finding suggests that vitamin D status is increased by regular small sun exposures (<2 SED_EFB per week), and that greater exposures result in only small additional increases in 25(OH)D₃.

Birth weight and subsequent body mass index in children: an international cross-sectional study

BACKGROUND

The reported association between birth weight and subsequent body mass index (BMI) is conflicting.

OBJECTIVES

To examine the relationship between birth weight and BMI in children aged 6-7 years.

METHODS

Secondary analysis of data from a multi-centre, multi-country, cross-sectional study (International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three). Parents/guardians of children aged 6-7 years completed questionnaires about their children's birth weight, current height and weight and whether their mother smoked in the first year of the child's life. A general linear mixed model was used to determine the association between BMI and birth weight.

RESULTS

A total of 72 111 children (17 countries) were included in the analysis. There was a positive association of birth weight with BMI (for each kg increase in birth weight the BMI at 6-7 increased by 0.47 (SE 0.02) kg/m² ; p < 0.0001) with a clear gradient by birth weight category. There was no statistically significant interaction between birth weight and Gross National Income (GNI).

CONCLUSIONS

There is a positive linear relationship between birth weight and BMI in 6-7 year old children, which is present in both high and low income countries.

Body mass index and vigorous physical activity in children and adolescents: an international cross-sectional study

AIM

To examine the relationship between reported vigorous physical activity (VPA) and body mass index (BMI) in children (6-7 years) and adolescents (13-14 years).

METHODS

In the International Study of Asthma and Allergies in Childhood Phase Three, 75 895 children's parents and 199 502 adolescents answered questions relating to VPA, height and weight. The association between VPA and BMI was analysed using general linear models, adjusting for country gross national index.

RESULTS

Compared to children who undertook no VPA, those in the infrequent group (once or twice per week) and those in the frequent group (three or more times per week) had mean (95% CI) BMI values 0.07 kg/m² (0.03-0.11) and 0.09 kg/m² (0.03-0.15) greater, respectively (p = 0.001). Compared to adolescents reporting no VPA, those in the infrequent group had a BMI 0.19 kg/m² (0.15-0.23) greater while those in the frequent group had a BMI 0.01 kg/m² (-0.03-0.05) greater (p < 0.0001).

CONCLUSION

Reported VPA is not associated with lower BMI among children and adolescents. Investigation of VPA and BMI may be best undertaken in conjunction with other variables in the energy expenditure equation. A focus on VPA alone may be an inefficient way to manage BMI.

The combination of bed sharing and maternal smoking leads to a greatly increased risk of sudden unexpected death in infancy: the New Zealand SUDI Nationwide Case Control Study

BACKGROUND

Despite a major reduction in overall infant mortality, sudden unexpected death in infancy (SUDI) continues to be of concern in New Zealand, as the rate is high by international standards, and is even higher in indigenous Māori.

AIM

To identify modifiable risk factors for SUDI.

METHODS

A three-year (1 March 2012-28 February 2015) nationwide case-control study was conducted in New Zealand.

RESULTS

There were 137 SUDI cases, giving a SUDI mortality rate of 0.76/1,000 live births. The rate for Māori was 1.41/1,000, Pacific 1.01/1,000 and non-Māori non-Pacific (predominantly European) 0.50/1,000. The parent(s) of 97% of the SUDI cases were interviewed. Six hundred and forty-nine controls were selected and 258 (40%) were interviewed. The two major risk factors for SUDI were: maternal smoking in pregnancy (adjusted OR=6.01, 95% CI=2.97, 12.15) and bed sharing (aOR=4.96, 95% CI=2.55, 9.64). There was a significant interaction (p=0.002) between bed sharing and antenatal maternal smoking. Infants exposed to both risk factors had a markedly increased risk of SUDI (aOR=32.8, 95% CI=11.2, 95.8) compared with infants not exposed to either risk factor. Infants not sharing the parental bedroom were also at increased risk of SUDI (aOR=2.77, 95% CI=1.45, 5.30). Just 21 cases over the three-year study were not exposed to smoking in pregnancy, bed sharing or front or side sleeping position.

CONCLUSIONS

This study has shown that many of the risk factors that were identified in the original New Zealand Cot Death Study (1987-1989) are still relevant today. The combination of maternal smoking in pregnancy and bed sharing is extremely hazardous for infants. Furthermore, our findings indicate that the SUDI prevention messages are still applicable today and should be reinforced. SUDI mortality could be reduced to just seven p.a. in New Zealand (approximately one in 10,000 live births).

Effect of monthly high-dose vitamin D supplementation on falls and non-vertebral fractures: secondary and post-hoc outcomes from the randomised, double-blind, placebo-controlled ViDA trial

BACKGROUND

Adults with low concentrations of 25-hydroxyvitamin D (25[OH]D) in blood have an increased risk of falls and fractures, but randomised trials of vitamin D supplementation have had inconsistent results. We aimed to assess the effect of high-dose vitamin D supplementation on fractures and falls.

METHODS

The Vitamin D Assessment (ViDA) Study was a randomised, double-blind, placebo-controlled trial of healthy volunteers aged 50-84 years conducted at one centre in Auckland, New Zealand. Participants were randomly assigned to receive either an initial oral dose of 200 000 IU (5·0 mg) colecalciferol (vitamin D₃) followed by monthly 100 000 IU (2·5 mg) colecalciferol or equivalent placebo dosing. The prespecified primary outcome was cardiovascular disease and secondary outcomes were respiratory illness and fractures. Here, we report secondary outcome data for fractures and post-hoc outcome data for falls. Cox proportional hazards models were used to estimate hazard ratios (HRs) for time to first fracture or time to first fall in individuals allocated vitamin D compared with placebo. The analysis of fractures included all participants who gave consent and was by intention-to-treat; the analysis of falls included all individuals who returned one or more questionnaires. This trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12611000402943.

FINDINGS

Between April 5, 2011, and Nov 6, 2012, 5110 participants were recruited and randomly assigned either colecalciferol (n=2558) or placebo (n=2552). Two participants allocated placebo withdrew consent after randomisation; thus, a total of 5108 individuals were included in the analysis of fractures. The mean age of participants was 65·9 years (SD 8·3) and 2971 (58%) were men. The mean concentration of 25(OH)D in blood was 63 nmol/L (SD 24) at baseline, with 1534 (30%) having 25(OH)D concentrations lower than 50 nmol/L. Follow-up was until July 31, 2015, with a mean treatment duration of 3·4 years (SD 0·4, range 2·5-4·2). During follow-up, 2638 participants reported having a fall, 1312 (52%) of 2539 in the vitamin D group compared with 1326 (53%) of 2517 in the placebo group. The HR for falls-adjusted for age, sex, ethnic origin, history of recent fall, physical activity, and baseline 25(OH)D-was 0·99 (95% CI 0·92-1·07; p=0·82) for vitamin D compared with placebo. Non-vertebral fractures were reported in 292 individuals, 156 (6%) of 2558 in the vitamin D group and 136 (5%) of 2550 in the placebo group. The adjusted HR for fractures was 1·19 (95% CI 0·94-1·50; p=0·15) for vitamin D compared with placebo. 123 (2%) people died during the trial, 65 assigned vitamin D and 58 allocated placebo; the difference between treatment groups was not significant.

INTERPRETATION

High-dose bolus vitamin D supplementation of 100 000 IU colecalciferol monthly over 2·5-4·2 years did not prevent falls or fractures in this healthy, ambulatory, adult population. Further research is needed to ascertain the effects of daily vitamin D dosing, with or without calcium.

FUNDING

Health Research Council of New Zealand and Accident Compensation Corporation of New Zealand.

The Vitamin D Assessment (ViDA) Study: design of a randomized controlled trial of vitamin D supplementation for the prevention of cardiovascular disease, acute respiratory infection, falls and non-vertebral fractures

Observational studies have shown that low vitamin D status is associated with an increased risk of cardiovascular disease, acute respiratory infection, falls and non-vertebral fractures. We recruited 5110 Auckland adults, aged 50-84 years, into a randomized, double-blind, placebo-controlled trial to test whether vitamin D supplementation protects against these four major outcomes. The intervention is a monthly cholecalciferol dose of 100,000IU (2.5mg) for an estimated median 3.3 years (range 2.5-4.2) during 2011-2015. Participants were recruited primarily from family practices, plus community groups with a high proportion of Maori, Pacific, or South Asian individuals. The baseline evaluation included medical history, lifestyle, physical measurements (e.g. blood pressure, arterial waveform, lung function, muscle function), and a blood sample (stored at -80°C for later testing). Capsules are being mailed to home addresses with a questionnaire to collect data on non-hospitalized outcomes and to monitor adherence and potential adverse effects. Other data sources include New Zealand Ministry of Health data on mortality, hospitalization, cancer registrations and dispensed pharmaceuticals. A random sample of 438 participants returned for annual collection of blood samples to monitor adherence and safety (hypercalcemia), including repeat physical measurements at 12 months follow-up. The trial will allow testing of a priori hypotheses on several other endpoints including: weight, blood pressure, arterial waveform parameters, heart rate variability, lung function, muscle strength, gait and balance, mood, psoriasis, bone density, and chronic pain.

Hypercalcemia, hypercalciuria, and kidney stones in long-term studies of vitamin D supplementation: a systematic review and meta-analysis

BACKGROUND

Vitamin D supplementation is increasingly being used in higher doses in randomized controlled trials (RCTs). However, adverse events from very large annual doses of vitamin D have been shown in 2 RCTs, whereas in a third RCT, low-dose vitamin D, with calcium supplements, was shown to increase kidney stone risk.

OBJECTIVE

We analyzed the side effects related to calcium metabolism in RCTs, specifically hypercalcemia, hypercalciuria, and kidney stones, in participants who were given vitamin D supplements for ≥24 wk compared with in subjects in the placebo arm.

DESIGN

The following 3 main online databases were searched: Ovid Medline (PubMed), EMBASE, and the Cochrane Library. Software was used for the meta-analysis.

RESULTS

A total of 48 studies with 19,833 participants were identified, which reported ≥1 of the following side effects: hypercalcemia, hypercalciuria, or kidney stones. Of these studies, kidney stones were reported in only 9 trials with a tendency for fewer subjects reporting stones in the vitamin D arm than in the placebo arm (RR: 0.66, 95% CI: 0.41, 1.09; P = 0.10). In 37 studies, hypercalcemia was shown with increased risk shown for the vitamin D group (RR: 1.54; 95% CI: 1.09, 2.18; P = 0.01). Similar increased risk of hypercalciuria was shown in 14 studies for the vitamin D group (RR: 1.64; 95% CI: 1.06, 2.53; P = 0.03). In subgroup analyses, it was shown that the effect of vitamin D supplementation on risk of hypercalcemia, hypercalciuria, or kidney stones was not modified by baseline 25-hydroxyvitamin D, vitamin D dose and duration, or calcium co-supplementation.

CONCLUSIONS

Long-term vitamin D supplementation resulted in increased risks of hypercalcemia and hypercalciuria, which were not dose related. However, vitamin D supplementation did not increase risk of kidney stones. Additional large RCTs of long-term vitamin D supplementation are required to confirm these findings.

Effect of Vitamin D Supplementation on Pain: A Systematic Review and Meta-analysis

BACKGROUND

There is conflicting evidence from previous qualitative reviews on the effect of vitamin D supplementation on pain.

OBJECTIVE

To determine with quantitative methods if vitamin D supplementation lowers pain levels.

STUDY DESIGN

Quantitative meta-analysis of published randomized controlled trials (RCTs).

SETTING

This meta-analysis examined all studies involving the effect of vitamin D supplementation on pain score.

METHOD

Electronic sources (Medline, Embase, Cochrane Central Register of Controlled Trials, clinical trials website, and Google scholar) were systematically searched for RCTs of vitamin D supplementation and pain from inception of each database to October 2015.

RESULTS

Nineteen RCTs with 3,436 participants (1,780 on vitamin D supplementation and 1,656 on placebo) were included in the meta-analysis. For the primary outcome (mean change in pain score from baseline to final follow-up), 8 trials with 1,222 participants on vitamin D and 1,235 on placebo reported a significantly greater mean decrease in pain score for the vitamin D group compared to placebo (mean difference -0.57, 95% CI: -1.00 to -0.15, P = 0.007). The effect from vitamin D was greater in patients recruited with pre-existing pain (P-value for interaction = 0.03). Fourteen studies (1,548 on vitamin D, 1,430 on placebo) reported the mean pain score at final follow-up outcome, and no statistical difference was observed (mean difference -0.06, 95%CI: -0.44 to 0.33, P = 0.78). In 4 studies which reported pain improvement (209 on vitamin D, 146 on placebo), the effect size although not significant, shows participants in the vitamin D supplementation group were more likely to report pain improvement compared with the placebo group (relative risk 1.38, 95%CI: 0.93 to 2.05, P = 0.11).

LIMITATIONS

Only a few studies reported the mean score change from baseline to final follow-up, and we do not have enough data to determine any modifying effect of baseline vitamin D status and different doses of vitamin D supplementation on pain.

CONCLUSION

A significantly greater mean decrease in pain score (primary outcome) was observed with vitamin D supplementation compared with placebo in people with chronic pain. These results suggest that vitamin D supplementation could have a role in the management of chronic pain.

KEY WORDS

Meta-analysis, pain, randomized controlled trials, vitamin D supplementation.

Does urban extent from satellite images relate to symptoms of asthma, rhinoconjunctivitis and eczema in children? A cross-sectional study from ISAAC Phase Three

OBJECTIVE

The relationship between urbanisation and the symptom prevalence of asthma, rhinoconjunctivitis and eczema is not clear, and varying definitions of urban extent have been used. Furthermore, a global analysis has not been undertaken. This study aimed to determine whether the symptom prevalence of asthma, rhinoconjunctivitis and eczema in centres involved in the International Study of Asthma and Allergies in Childhood (ISAAC) were higher in urban than rural centres, using a definition of urban extent as land cover from satellite data.

METHODS

A global map of urban extent from satellite images (MOD500 map) was used to define the urban extent criterion. Maps from the ISAAC centres were digitised and merged with the MOD500 map to describe the urban percentage of each centre. We investigated the association between the symptom prevalence of asthma, rhinoconjunctivitis and eczema and the percentage of urban extent by centre.

RESULTS

A weak negative relationship was found between the percentage of urban extent of each ISAAC centre and current wheeze in the 13-14-year age group. This association was not statistically significant after adjusting for region of the world and gross national income. No other relationship was found between urban extent and symptoms of asthma, rhinoconjunctivitis and eczema.

CONCLUSIONS

In this study, the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema in children were not associated with urbanisation, according to the land cover definition of urban extent from satellite data. Comparable standardised definitions of urbanisation need to be developed so that global comparisons can be made.

A description of sleep behaviour in healthy late pregnancy, and the accuracy of self-reports

Background

The importance of maternal sleep and its contribution to maternal and fetal health during pregnancy is increasingly being recognised. However, the ability to accurately recall sleep practices during pregnancy has been questioned. The aim of this study is to test the accuracy of recall of normal sleep practices in late pregnancy.

Methods

Thirty healthy women between 35 and 38 weeks of gestation underwent level III respiratory polysomnography (PSG) with infrared digital video recordings in their own homes. Data regarding sleep positions, number of times getting out of bed during the night and respiratory measures were collected. A sleep questionnaire was administered the morning after the recorded sleep. Continuous data were assessed using Spearman’s Rho and Bland-Altman. Cohen’s Kappa was used to assess recall in the categorical variables.

Results

Two-thirds of participants went to sleep on their left side. There was good agreement in sleep onset position between video and questionnaire data (Kappa 0.52), however the there was poor agreement on position on wakening (Kappa 0.24). The number of times getting out of bed during the night was accurately recalled (Kappa 0.65). Twenty five out of 30 participants snored as recorded by PSG. Questionnaire data was inaccurate for this measure. Bland-Altman plots demonstrated acceptable agreement between video and questionnaire data for estimated sleep duration, but not the time taken to fall asleep (sleep latency). One participant had mild obstructive sleep apnoea and another probable high upper airways resistance.

Conclusions

Sleep onset position, sleep duration and the number of times getting out of bed during the night were accurately recalled, but sleep latency and sleep position on waking were not. This study identifies the sleep variables that can be accurately obtained by questionnaire and those that cannot.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-0905-0) contains supplementary material, which is available to authorized users.

Factors associated with medication adherence in school-aged children with asthma

Adherence to preventive asthma treatment is poor, particularly in children, yet the factors associated with adherence in this age group are not well understood.

Adherence was monitored electronically over 6 months in school-aged children who attended a regional emergency department in New Zealand for an asthma exacerbation and were prescribed twice-daily inhaled corticosteroids. Participants completed questionnaires including assessment of family demographics, asthma responsibility and learning style. Multivariable analysis of factors associated with adherence was conducted.

101 children (mean (range) age 8.9 (6–15) years, 51% male) participated. Median (interquartile range) preventer adherence was 30% (17–48%) of prescribed. Four explanatory factors were identified: female sex (+12% adherence), Asian ethnicity (+19% adherence), living in a smaller household (−3.0% adherence per person in the household), and younger age at diagnosis (+2.7% for every younger year of diagnosis) (all p<0.02).

In school-aged children attending the emergency department for asthma, males and non-Asian ethnic groups were at high risk for poor inhaled corticosteroid adherence and may benefit most from intervention. Four factors explained a small proportion of adherence behaviour indicating the difficulty in identifying adherence barriers. Further research is recommended in other similar populations.

Girls, children of Asian ethnicity, small household size and younger diagnosis age have better adherence to asthmahttp://ow.ly/Z1y6Q

Factors associated with photoprotection by body clothing coverage, particularly in non-summer months, among a New Zealand community sample

Clothing coverage is important for reducing skin cancer risk, but may also influence vitamin D sufficiency, so associated plausible predictors require investigation. Volunteers (18 to 85 years), with approximately equal numbers by sex and four ethnicity groups, were recruited in cities from two latitude bands: Auckland (36.9°S) and Dunedin (45.9°S). Baseline questionnaire, anthropometric and spectrophotometer skin colour data were collected and weather data obtained. Percent body coverage was calculated from eight week diary records. Potential independent predictors (unadjusted p < 0.25) were included in adjusted models. Participants (n = 506: Auckland n = 334, Dunedin n = 172; mean age 48.4 years) were 62.7% female and had a median body clothing coverage of 81.6% (IQR 9.3%). Dunedin was cooler, less windy and had lower UVI levels than Auckland. From the fully adjusted model, increased coverage occurred in non-summer months (despite adjusting for weather), among Dunedin residents and Asians (compared to Europeans), during the middle of the day, with a dose response effect observed for greater age. Reduced coverage was associated with Pacific ethnicity and greater time spent outdoors. Additionally, higher temperatures were associated with reduced coverage, whereas increased cloud cover and wind speed were associated with increased coverage. Although the only potentially modifiable factors associated with clothing coverage were the time period and time spent outdoors, knowledge of these and other associated factors is useful for the framing and targeting of health promotion messages to potentially influence clothing coverage, facilitate erythema avoidance and maintain vitamin D sufficiency.

Vitamin D activity of breast milk in women randomly assigned to vitamin D3 supplementation during pregnancy

BACKGROUND

Human milk is typically low in vitamin D activity (VDA). Whether the vitamin D content of breast milk at birth can be increased by supplementing the mother during pregnancy has not been reported to the best of our knowledge.

OBJECTIVE

We examined the effect of vitamin D supplementation during pregnancy on breast-milk VDA in the first 2 mo of lactation.

DESIGN

Breast-milk samples were obtained from women who were enrolled in a randomized, double-blinded, placebo-controlled trial of vitamin D supplementation during pregnancy. Pregnant women were enrolled at 27 wk of gestation and randomly assigned to the following 3 groups: a placebo group, a group who received one dosage of daily oral vitamin D3 (1000 IU), or a group who received 2 dosages of daily oral vitamin D3 (2000 IU). Serum 25-hydroxyvitamin D [25(OH)D] was measured at enrollment, at 36 wk of gestation, and in cord blood at birth. Study participants who were breastfeeding were invited to provide breast-milk samples for VDA measurement [concentration of vitamin D2, vitamin D3, 25(OH)D2, and 25(OH)D3] at 2 wk and 2 mo postpartum. A linear mixed model was used to compare breast-milk VDA between the 3 study groups.

RESULTS

A total of 75 women provided breast-milk samples (44 women provided breast-milk samples at both 2 wk and 2 mo postpartum). The mean (95% CI) VDA at age 2 wk was 52 IU/L (12, 217 IU/L) in the placebo group, 51 IU/L (17, 151 IU/L) in the 1000-IU group, and 74 IU/L (25, 221 IU/L) in the 2000-IU group; and at age 2 mo, the mean (95% CI) VDA was 45 IU/L (16, 124 IU/L), 43 IU/L (18, 103 IU/L), and 58 IU/L (15, 224 IU/L), respectively. There was no significant interaction in VDA between the sample-collection time and treatment (P = 0.61), but there was a difference between lower- and higher-dosage treatment groups (P = 0.04).

CONCLUSION

Maternal vitamin D supplementation during pregnancy of 2000 IU/d (compared with 1000 IU/d and with a placebo) results in a higher VDA of breast milk ≥2 mo postpartum. This trial was registered at the Australian New Zealand Clinical Trials Registry as ACTRN12610000483055.

Maternal post-natal tobacco use and current parental tobacco use is associated with higher body mass index in children and adolescents: an international cross-sectional study

BACKGROUND

We investigated whether maternal smoking in the first year of life or any current parental smoking is associated with childhood or adolescent body mass index (BMI).

METHODS

Secondary analysis of data from a multi-centre, multi-country, cross-sectional study (ISAAC Phase Three). Parents/guardians of children aged 6-7 years completed questionnaires about their children's current height and weight, whether their mother smoked in the first year of the child's life and current smoking habits of both parents. Adolescents aged 13-14 years completed questionnaires about their height, weight and current parental smoking habits. A general linear mixed model was used to determine the association between BMI and parental smoking.

RESULTS

77,192 children (18 countries) and 194 727 adolescents (35 countries) were included. The BMI of children exposed to maternal smoking during their first year of life was 0.11 kg/m(2) greater than those who were not (P = 0.0033). The BMI of children of currently smoking parents was greater than those with non-smoking parents (maternal smoking: +0.08 kg/m(2) (P = 0.0131), paternal smoking: +0.10 kg/m(2) (P < 0.0001)). The BMI of female adolescents exposed to maternal or paternal smoking was 0.23 kg/m(2) and 0.09 kg/m(2) greater respectively than those who were not exposed (P < 0.0001). The BMI of male adolescents was greater with maternal smoking exposure, but not paternal smoking (0.19 kg/m(2), P < 0.0001 and 0.03 kg/m(2), P = 0.14 respectively).

CONCLUSION

Parental smoking is associated with higher BMI values in children and adolescents. Whether this is due to a direct effect of parental smoking or to confounding cannot be established from this observational study.

Association between breastfeeding and body mass index at age 6-7 years in an international survey

BACKGROUND

Breastfeeding is believed to reduce children's risk for obesity but data are conflicting. It is also uncertain if breastfeeding has different effects on obesity in high- and low-income countries.

OBJECTIVES

This study aimed to investigate the association between having been breastfed and body mass index (BMI) in 6- to 7-year-old children in a large international survey.

METHODS

Parents/guardians reported whether their child had been breastfed and their current height and weight. Some centres measured height and weight directly. Analyses adjusted for whether height and weight were reported or measured, child's age, sex, country gross national income and centre.

RESULTS

Data were available for 76,635 participants from 31 centres in 18 countries. Reported breastfeeding rates varied from 27 to 98%. After adjusting for potential confounders, the estimated BMI difference was 0.04 kg m(-2) lower among those who had been breastfed (P = 0.07). The risk for being overweight or obese was slightly lower among breastfed children (odds ratio = 0.95, P = 0.012). There was no evidence that the association between breastfeeding and BMI was different in lower income countries compared with higher income countries.

CONCLUSIONS

The findings suggest that breastfeeding has little impact on children's BMI. Increasing breastfeeding is unlikely to reduce the global epidemic of childhood obesity.

Association between paracetamol use in infancy or childhood with body mass index

OBJECTIVE

Paracetamol has the potential to also promote weight gain by indirect activation of cannabinoid receptors. The association between paracetamol use in the first 12 months of life or recent high use and BMI in children and adolescents was investigated.

METHODS

Paracetamol use in the first 12 months of life (reported by parents/guardians of 6- and 7-year-olds) or in the past 12 months (reported by parents/guardians of 6- and 7-year-olds or self-reported by adolescents aged 13-14) was examined in relation to BMI in a large multicentre cross-sectional study (2000-2003). Linear regression results were adjusted for whether height and weight were reported or measured, age, sex, country gross national income, study centre, maternal smoking, and recent wheeze.

RESULTS

Data were available from 76,216 children (18 countries) and 188,469 adolescents (35 countries). BMI was +0.07 kg/m2 higher in children with early life paracetamol exposure, from affluent countries only. Frequent recent paracetamol use was associated with higher BMI (+0.17 kg/m2, P < 0.0001) among adolescents from affluent countries only, but not in children (P = 0.41).

CONCLUSIONS

Paracetamol may be causally related to increased BMI; alternatively, the association may be explained by lifestyle or other factors that correlate with paracetamol use in affluent countries.

Validation of thoracic impedance cardiography by echocardiography in healthy late pregnancy

Background

Assessment of stroke volume (SV) is often necessary in clinical and research settings. The clinically established method for SV assessment in pregnancy is echocardiography, but given its limitations, it is not always an appropriate measurement tool. Thoracic impedance cardiography (ICG) allows continuous, non-invasive SV assessment. However, SV determination relies on assumptions regarding the thoracic shape that may mean the algorithm is not valid in pregnancy. The available data regarding the validity of ICG against an established reference standard using modern SV algorithms are both limited and conflicting. We aimed to test the validity of ICG in a clinically realistic setting in late pregnancy using echocardiography.

Methods

Twenty-nine women in late pregnancy underwent standard echocardiography assessments with simultaneous ICG measurement. Agreement between devices was tested using Bland-Altman analysis.

Results

Bland-Altman analysis of the relationship between ICG and echocardiography demonstrated that the 95% limits of agreement exceeded acceptable or expected ranges. Measures of maternal and fetal anthropometry do not account for the lack of agreement.

Conclusions

Absolute values of SV as determined by ICG are not valid in pregnancy. Further work is required to examine the ability of ICG to assess relative changes in maternal haemodynamics in late pregnancy.

The effect of an electronic monitoring device with audiovisual reminder function on adherence to inhaled corticosteroids and school attendance in children with asthma: a randomised controlled trial

BACKGROUND

Suboptimum adherence to preventive asthma treatment is associated with substantial morbidity and mortality, yet adherence often remains poor. We aimed to investigate whether use of an inhaler with audiovisual reminders leads to improved adherence and asthma outcomes in school-aged children who presented to the emergency department with an asthma exacerbation.

METHODS

We did a randomised controlled trial in patients aged 6-15 years who attended the regional emergency department in Auckland, New Zealand with an asthma exacerbation and were on regular inhaled corticosteroids. Using a simple, unrestricted block randomisation with block sizes of 200, we randomly assigned patients to receive an electronic monitoring device for use with their preventer inhaler with the audiovisual reminder functions either enabled to support adherence to inhaled corticosteroids (intervention group) or disabled (control group). Participants were followed up every 2 months for 6 months. The primary outcomes were adherence to preventive inhaled corticosteroids and number of days absent from school for any reason. Asthma control was assessed as a secondary outcome. All analyses were done in the intention-to-treat population. This trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12613001353785.

FINDINGS

The study took place between May 10, 2010, and Feb 26, 2012. We randomly assigned 220 patients, 110 to the intervention group and 110 to the control group. Median percentage adherence was 84% (10th percentile 54%, 90th percentile 96%) in the intervention group, compared with 30% (8%, 68%) in the control group (p<0·0001). The proportion of days absent from school for any reason was 1·9% (10th percentile 0·0%, 90th percentile 7·9%) in the intervention group and 1·7% (0·0%, 8·6%) in the control group. The change in asthma morbidity score from baseline to 6 months was significantly greater in the intervention group than in the control group (p=0·008), with a reduction of 2·0 points from a mean baseline score of 9·3 (SD 2·2) to 7·3 (2·1) in the intervention group, compared with a reduction of 1·2 points from a baseline of 9·2 (2·5) to 8·0 (2·2) in the control group.

INTERPRETATION

Use of an electronic monitoring device with an audiovisual reminder led to significant improvements in adherence to inhaled corticosteroids in school-aged children with asthma. This intervention could be beneficial for the improvement of asthma control in patients for whom poor asthma control is related to poor adherence.

FUNDING

Health Research Council of New Zealand and Cure Kids.

Effect of monthly vitamin D3 supplementation in healthy adults on adverse effects of earthquakes: randomised controlled trial

OBJECTIVE

To determine whether supplementation with vitamin D improves resilience to the adverse effects of earthquakes.

DESIGN

Opportunistic addition to an established randomised double blind placebo controlled trial.

SETTING

Christchurch, New Zealand, where a prolonged series of catastrophic earthquakes beginning on 4 September 2010 occurred, which caused widespread destruction, fatalities, and extensive psychological damage.

PARTICIPANTS

322 healthy adults (241 women; 81 men) aged 18-67 who were already participating in the vitamin D and acute respiratory infections study (VIDARIS) between February 2010 and November 2011.

INTERVENTION

Participants were randomised to receive an oral dose of either 200,000 IU vitamin D3 monthly for two months then 100,000 IU monthly (n=161) or placebo (n=161) for a total of 18 months.

MAIN OUTCOME MEASURE

This is a post hoc analysis from the previously published VIDARIS trial. The primary endpoint in the current analysis was the self reported effects and overall adverse impact of the Christchurch earthquakes as assessed by questionnaire four months after the most destructive earthquake on 22 February 2011, which was used as the index event. The secondary end point was the number of "psychological" adverse events that participants reported at their usual monthly appointments as part of the original VIDARIS trial.

RESULTS

308 participants completed the earthquake impact questionnaire (n=152 in the vitamin D group and 156 in the placebo group). There was no significant difference in the number of self reported adverse effects between those receiving vitamin D supplementation and those receiving placebo. There was also no difference in the overall adverse impact score between treatment groups (χ(2) P=0.44). The exception was that those in the vitamin D group experienced more adverse effects on family relationships (22% v 13%; χ(2) P=0.03). The number of psychological adverse events-such as fatigue, stress, anxiety, and insomnia-that participants reported at their usual monthly appointments was significantly higher after the earthquake (χ(2) P=0.007) but did not differ between treatment groups.

CONCLUSION

In this trial, vitamin D supplementation did not reduce the adverse impact of earthquakes in healthy adults. Trial registration Australian New Zealand Clinical Trials Registry (anzctr.org.au) ACTRN12609000486224.

Fast-food consumption and body mass index in children and adolescents: an international cross-sectional study

OBJECTIVE

To investigate whether reported fast-food consumption over the previous year is associated with higher childhood or adolescent body mass index (BMI).

DESIGN

Secondary analysis from a multicentre, multicountry cross-sectional study (International Study of Asthma and Allergies in Children (ISAAC) Phase Three).

SUBJECTS AND METHODS

Parents/guardians of children aged 6-7 completed questionnaires which included questions about their children's asthma and allergies, fast-food consumption, height and weight. Adolescents aged 13-14 completed the same questionnaire. The questionnaire asked "In the past 12 months, how often on average did you (your child) eat fast-food/burgers?" The responses were infrequent (never/only occasionally), frequent (once/twice a week) or very frequent (three or more times per week). A general linear mixed model was used to determine the association between BMI and fast-food consumption, adjusting for Gross National Income per capita by country, measurement type (whether heights/weights were reported or measured), age and sex.

RESULTS

72,900 children (17 countries) and 199,135 adolescents (36 countries) provided data. Frequent and very frequent fast-food consumption was reported in 23% and 4% of children, and 39% and 13% of adolescents, respectively. Children in the frequent and very frequent groups had a BMI that was 0.15 and 0.22 kg/m(2) higher than those in the infrequent group (p<0.001). Male adolescents in the frequent and very frequent groups had a BMI that was 0.14 and 0.28 kg/m(2) lower than those in the infrequent group (p<0.001). Female adolescents in the frequent and very frequent groups had a BMI that was 0.19 kg/m(2) lower than those in the infrequent group (p<0.001).

CONCLUSIONS

Reported fast-food consumption is high in childhood and increases in adolescence. Compared with infrequent fast-food consumption, frequent and very frequent consumption is associated with a higher BMI in children. Owing to residual confounding, reverse causation and likely misreporting, the reverse association observed in adolescents should be interpreted with caution.

Long-Term High-Dose Vitamin D 3 Supplementation and Blood Pressure in Healthy Adults

Previous randomized controlled trials of vitamin D supplementation and blood pressure (BP) mainly have given vitamin D for short periods (<6 months) or at low doses (400 IU per day). This study aims to determine whether long-term high-dose vitamin D taken for 18 months lowers BP. Adults were recruited from a healthcare organization or university into a double-blind controlled trial and randomized to receive either vitamin D 3 200 000 IU for 2 months followed by 100 000 IU monthly up to 18 months (n=161) or placebo (n=161). BP was measured at baseline, 5, and 18 months. Subjects had a mean (SD) age of 47.6 (9.7) years, 75% were women, and 94% were of European ancestry (white). Mean (SD) 25-hydroxyvitamin D 3 changed from 73 (22) nmol/L at baseline to 124 (28) nmol/L at 18 months in the vitamin D group, and from 71 (22) nmol/L to 56 (22) nmol/L in the placebo group. Mean BP was similar for the vitamin D and placebo groups at baseline (123.4/76.3 versus 122.6/75.6 mm Hg; respectively). The mean change (95% confidence interval) in BP at 18 months minus baseline in the vitamin D group compared with placebo group was −0.6 (−2.8 to 1.6) mm Hg for systolic ( P =0.61) and 0.5 (−1.1, 2.2) mm Hg for diastolic ( P =0.53). Long-term vitamin D supplementation, which increased mean 25-hydroxyvitamin D 3 concentration >100 nmol/L for 18 months, had no effect on systolic or diastolic BP in predominantly white, healthy adults without severe vitamin D deficiency. Beneficial effects on BP cannot be ruled out for other populations.

Vitamin D during pregnancy and infancy and infant serum 25-hydroxyvitamin D concentration

OBJECTIVE

To determine the vitamin D dose necessary to achieve serum 25-hydroxyvitamin D (25(OH)D) concentration ≥ 20 ng/mL during infancy.

METHODS

A randomized, double-blind, placebo-controlled trial in New Zealand. Pregnant mothers, from 27 weeks' gestation to birth, and then their infants, from birth to age 6 months, were randomly assigned to 1 of 3 mother/infant groups: placebo/placebo, vitamin D3 1000/400 IU, or vitamin D3 2000/800 IU. Serum 25(OH)D and calcium concentrations were measured at enrollment, 36 weeks' gestation, in cord blood, and in infants at 2, 4, and 6 months of age.

RESULTS

Two-hundred-and-sixty pregnant women were randomized. At enrollment, the proportions with serum 25(OH)D ≥ 20 ng/mL for placebo, lower-dose, and higher-dose groups were 54%, 64%, and 55%, respectively. The proportion with 25(OH)D ≥ 20 ng/mL was larger in both intervention groups at 36 weeks' gestation (50%, 91%, 89%, P < .001). In comparison with placebo, the proportion of infants with 25(OH)D ≥ 20 ng/mL was larger in both intervention groups to age 4 months: cord blood (22%, 72%, 71%, P < .001), 2 months (50%, 82%, 92%, P < .001), and 4 months (66%, 87%, 87%, P = .004), but only in the higher-dose group at age 6 months (74%, 82%, 89%, P = .07; higher dose versus placebo P = .03, lower dose versus placebo P = .21).

CONCLUSIONS

Daily vitamin D supplementation during pregnancy and then infancy with 1000/400 IU or 2000/800 IU increases the proportion of infants with 25(OH)D ≥ 20 ng/mL, with the higher dose sustaining this increase for longer.

Antibiotic treatment during infancy and increased body mass index in boys: an international cross-sectional study

OBJECTIVE

To investigate whether antibiotic exposure during the first year of life is associated with increased childhood body mass index (BMI).

DESIGN

Secondary analysis from a multi-centre, multi-country, cross-sectional study (The International Study of Asthma and Allergies in Childhood Phase Three).

SUBJECTS

A total of 74 946 children from 31 centres in 18 countries contributed data on antibiotic use in the first 12 months of life and current BMI.

METHODS

Parents/guardians of children aged 5-8 years completed questionnaires that included questions about their children's current height and weight, and whether in the child's first 12 months of life, they had received any antibiotics, paracetamol, were breastfed or the mother/female guardian smoked cigarettes, and whether the child had wheezed in the past 12 months. A general linear mixed model was used to determine the association of antibiotic exposure with BMI, adjusting for age, sex, centre, BMI measurement type (self-reported or measured), maternal smoking, breastfeeding, paracetamol use, gross national income and current wheeze.

RESULTS

There was a significant interaction between sex and early-life antibiotic exposure. Early-life antibiotic exposure was associated with increased childhood BMI in boys (+0.107 kg m(-2), P<0.0001), but not in girls (-0.008 kg m(-2), P=0.75) after controlling for age, centre and BMI measurement type. The association remained in boys (+0.104 kg m(-2), P<0.0007), after adjustment for maternal smoking, breastfeeding, paracetamol use and current wheeze. There was no interaction between age, maternal smoking, breastfeeding, paracetamol use, gross national income and current wheeze in the association between early antibiotic exposure and BMI.

CONCLUSIONS

Exposure to antibiotics during the first 12 months of life is associated with a small increase in BMI in boys aged 5-8 years in this large international cross-sectional survey. By inference this provides additional support for the importance of gut microbiota in modulating the risk of obesity, with a sex-specific effect.

The worldwide association between television viewing and obesity in children and adolescents: cross sectional study

Background

Studies exploring the effect of television viewing on obesity throughout childhood are conflicting. Most studies have been confined to single high-income countries. Our aim was to examine the association between television viewing habits and Body Mass Index (BMI) in adolescents and children in a multicentre worldwide sample.

Methods

In the International Study of Asthma and Allergies in Children Phase Three, adolescents aged between 12 and 15 years completed questionnaires which included questions on television viewing habits, height and weight. Parents/guardians of children aged between 5 and 8 years completed the same questionnaire on behalf of their children. The questionnaire asked “During a normal week, how many hours a day (24 hours) do you (does your child) watch television?” Responses were categorised as; “short” (<1 hour), “moderate” (1 to ≤3 hours), “long” (3 to ≤5 hours) and “prolonged” (>5 hours).

Findings

207,672 adolescents from 37 countries and 77,003 children from 18 countries provided data. Daily television viewing in excess of one hour was reported in 89% of adolescents and 79% of children. Compared with adolescents in the short viewing group, those in the moderate, long and prolonged groups had BMIs that were 0.14 kg/m², 0.21 kg/m², 0.30 kg/m² and 0.08 kg/m², 0.16 kg/m² and 0.17 kg/m² larger for females and males respectively (both P<0.001). Compared with children in the short viewing group, those in the moderate, long and prolonged groups had BMIs that were 0.24 kg/m², 0.34 kg/m², 0.36 kg/m² and 0.19 kg/m², 0.32 kg/m² and 0.36 kg/m² larger for females and males respectively (both P<0.001).

Interpretation

Increased television viewing hours were positively associated with BMI in both adolescents and children with an apparent dose response effect. These findings extend the evidence that television viewing contributes to increased BMI in childhood.

Effect of vitamin D3 supplementation on Staphylococcus aureus nasal carriage: a randomized, double-blind, placebo-controlled trial in healthy adults

Observational studies have reported an inverse association between serum 25-hydroxyvitamin D (25OHD) concentrations and Staphylococcus aureus nasal carriage; however, clinical trials of vitamin D supplementation are lacking. To assess the effect of vitamin D3 supplementation on persistent S. aureus nasal carriage we conducted a randomized, double-blind, placebo-controlled trial among 322 healthy adults. Participants were given an oral dose of either 200 000 IU vitamin D3 for each of 2 months, followed by 100 000 IU monthly or placebo in an identical dosing regimen, for a total of 18 months. Nasal swabs for S. aureus culture and serum for 25OHD measurement were obtained at baseline, 6, 12 and 18 months of study. The mean baseline concentration of 25OHD was 72 nM (SD 22 nM). Vitamin D3 supplementation increased 25OHD levels which were maintained at >120 nM throughout the study. Nasal colonization by S. aureus was found in 31% of participants at baseline. Persistent carriage, defined as those that had positive S. aureus nasal cultures for all post-baseline swabs, occurred in 20% of the participants but vitamin D3 supplementation was not associated with a reduction in persistent carriage (OR = 1.39, 95% CI 0.63-3.06). Risk factor analysis showed that only gender was significantly associated with carriage, where women were less likely to be carriers than men (relative risk 0.83, 95% CI 0.54-0.99). Serum 25OHD concentrations were not associated with the risk of carriage. In conclusion, monthly administration of 100 000 IU of vitamin D3 did not reduce persistent S. aureus nasal carriage.

Time trends, ethnicity and risk factors for eczema in New Zealand children: ISAAC Phase Three

BACKGROUND

Eczema is a common chronic disease which has significant morbidity and costs for children and their families. Phase One (1993) of the International Study of Asthma and Allergies in Childhood (ISAAC) found a high prevalence of symptoms of eczema in New Zealand.

OBJECTIVE

In Phase Three (2001-3) we aimed to answer these three questions: Is the prevalence of eczema changing over time?; Are there ethnic differences in prevalence?; and What are the risk factors for eczema?

METHODS

Five New Zealand centres participated in ISAAC Phases One and Three using the same methodology. Questionnaires about ethnicity, symptoms of eczema and environmental factors were completed by parents of 6-7 year olds (children) and self-completed by 13-14 year olds (adolescents). Prevalence and change per year were calculated by centre, ethnicity and gender. Prevalence differences between centres and associations with environmental factors were examined using logistic regression.

RESULTS

There was little change in prevalence over time for the children, and a decrease in prevalence for the adolescents. Prevalence was higher among Māori and even higher among Pacific participants than among European children. Positive associations with current eczema symptoms were found for both age groups for truck traffic in the street of residence, and current paracetamol consumption, and for children only, antibiotics or paracetamol in the 1st year of life. Inverse associations were found with residence in New Zealand less than 5 years, consumption of milk, seafood, and eggs, and presence of a dog in the home.

CONCLUSION

Eczema remains a significant problem, particularly for young Māori and Pacific New Zealanders in whom less recognition of eczema and poorer access to effective, sustained eczema management may be contributing factors. Reverse causation may explain all the environmental findings apart from truck traffic which is increasing in New Zealand.

A postal survey of maternal sleep in late pregnancy

Background

Sleep disturbances in late pregnancy are common. This study aimed to survey sleep problems in third trimester pregnant women and to compare sleep in the pre-pregnancy period with the third trimester.

Methods

Third-trimester women (n=650) were sent a postal survey containing questions relating to sleep experience, including perceived sleep quality, sleep difficulties, night waking, sleep environment, snoring, daytime tiredness and daytime napping. Time periods reported on were before pregnancy and in the last week.

Results

Respondents numbered 244 (38%). Before pregnancy, the mean reported duration of night-time sleep was 8.1 (SD 1.1) hours; in the last week this had decreased to 7.5 (SD 1.8) hours (p<.0001). Only 29% rated their sleep quality in the last week as very good or fairly good, compared with 82% rating their sleep this way before the pregnancy. The main reasons for sleeping difficulties were discomfort (67%) and pain (36%). Snoring increased significantly over the course of the pregnancy, with 37% reporting snoring often or every night in the last week. Those with a pre-pregnancy body mass index of greater than 25 were significantly more likely to snore (p=.01). Only 4% of women had an abnormal Epworth Sleepiness Scale score (i.e. >10) prior to pregnancy, whereas in the last week 33% scored in the abnormal range. Likewise, 5% had regularly napped during the daytime before pregnancy, compared with 41% in the last week.

Conclusions

Sleep problems are common in women in late pregnancy, and increase markedly compared with before pregnancy.

Independent risk factors for infants who are small for gestational age by customised birthweight centiles in a multi-ethnic New Zealand population

BACKGROUND

Infants born small for gestational age (SGA) by customised birthweight centiles are at increased risk of adverse outcomes compared with those SGA by population centiles. Risk factors for customised SGA have not previously been described in a general obstetric population.

AIM

To determine independent risk factors for customised SGA in a multi-ethnic New Zealand population.

METHODS

We performed a retrospective cohort analysis of prospectively recorded maternity data from 2006 to 2009 at National Women's Health, Auckland, New Zealand. After exclusion of infants with congenital anomalies and missing data, our final study population was 26,254 singleton pregnancies. Multivariable logistic regression analysis adjusted for ethnicity, body mass index, maternal age, parity, smoking status, social deprivation, hypertensive disease, antepartum haemorrhage (APH), diabetes and relevant pre-existing medical conditions.

RESULTS

Independent risk factors for SGA included obesity (adjusted odds ratio 1.24 [95% CI 1.11-1.39] relative to normal weight), maternal age ≥ 35 years (1.16 [1.05-1.30] relative to 20-29 years), nulliparity (1.13 [1.04-1.24] relative to parity 1), cigarette smoking (2.01 [1.79-2.27]), gestational hypertension (1.46 [1.21-1.75]), pre-eclampsia (2.94 [2.49-3.48]), chronic hypertension (1.68 [1.34-2.09]), placental abruption (2.57 [1.74-3.78]) and APH of unknown origin (1.71 [1.45-2.00]). Gestational diabetes (0.80 [0.67-0.96]) and type 1 diabetes (0.26 [0.11-0.64]) were associated with reduced risk.

CONCLUSIONS

We report independent pregnancy risk factors for customised SGA in a general obstetric population. In contrast to population SGA, obesity is associated with increased risk. Our findings may help identify pregnancies that require increased fetal growth surveillance.

Effect of vitamin D3 supplementation on upper respiratory tract infections in healthy adults: the VIDARIS randomized controlled trial

CONTEXT

Observational studies have reported an inverse association between serum 25-hydroxyvitamin D (25-OHD) levels and incidence of upper respiratory tract infections (URTIs). However, results of clinical trials of vitamin D supplementation have been inconclusive.

OBJECTIVE

To determine the effect of vitamin D supplementation on incidence and severity of URTIs in healthy adults.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind, placebo-controlled trial conducted among 322 healthy adults between February 2010 and November 2011 in Christchurch, New Zealand.

INTERVENTION

Participants were randomly assigned to receive an initial dose of 200,000 IU oral vitamin D3, then 200,000 IU 1 month later, then 100,000 IU monthly (n = 161), or placebo administered in an identical dosing regimen (n = 161), for a total of 18 months.

MAIN OUTCOME MEASURES

The primary end point was number of URTI episodes. Secondary end points were duration of URTI episodes, severity of URTI episodes, and number of days of missed work due to URTI episodes.

RESULTS

The mean baseline 25-OHD level of participants was 29 (SD, 9) ng/mL. Vitamin D supplementation resulted in an increase in serum 25-OHD levels that was maintained at greater than 48 ng/mL throughout the study. There were 593 URTI episodes in the vitamin D group and 611 in the placebo group, with no statistically significant differences in the number of URTIs per participant (mean, 3.7 per person in the vitamin D group and 3.8 per person in the placebo group; risk ratio, 0.97; 95% CI, 0.85-1.11), number of days of missed work as a result of URTIs (mean, 0.76 days in each group; risk ratio, 1.03; 95% CI, 0.81-1.30), duration of symptoms per episode (mean, 12 days in each group; risk ratio, 0.96; 95% CI, 0.73-1.25), or severity of URTI episodes. These findings remained unchanged when the analysis was repeated by season and by baseline 25-OHD levels.

CONCLUSION

In this trial, monthly administration of 100,000 IU of vitamin D did not reduce the incidence or severity of URTIs in healthy adults.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12609000486224.

Ethnicity, body mass index and risk of pre-eclampsia in a multiethnic New Zealand population

BACKGROUND

Pre-eclampsia rates are reported to vary by ethnicity; however, few studies include body mass index (BMI). Increasing BMI has a dose-dependent relationship with pre-eclampsia, and rates of overweight and obesity as well as ratios of body fat to muscle mass differ between ethnicities. We hypothesised that after adjusting for confounders, including ethnic-specific BMI, ethnicity would not be an independent risk factor for pre-eclampsia.

AIM

To assess independent pre-eclampsia risk factors in a multiethnic New Zealand population.

METHODS

We performed a retrospective cohort analysis of prospectively recorded maternity data from 2006 to 2009 at National Women's Health, Auckland, New Zealand. After exclusion of infants with congenital anomalies and missing data, our final study population was 26 254 singleton pregnancies. Multivariable logistic regression analysis adjusted for ethnicity, BMI, maternal age, parity, smoking, social deprivation, diabetes, chronic hypertension and relevant pre-existing medical conditions was performed.

RESULTS

Independent associations with pre-eclampsia were observed in Chinese (adjusted odds ratio (aOR) 0.56, [95% CI 0.41-0.76]) and Māori (aOR 1.51, [1.16-1.96]) compared with European women. Other independent risk factors for pre-eclampsia were overweight and obesity, nulliparity, type 1 diabetes, chronic hypertension and pre-existing medical conditions.

CONCLUSIONS

Contrary to our hypothesis, we report an independent reduced risk of pre-eclampsia in Chinese and increased risk of pre-eclampsia in Māori women. Prospective studies are required to further explore these relationships. Other independent risk factors are consistent with international literature. Our findings may assist clinicians to stratify risk of pre-eclampsia in clinical practice.

Time trends and risk factors for rhinoconjunctivitis in New Zealand children: an International Study of Asthma and Allergies in Childhood (ISAAC) survey

AIM

To investigate prevalence, time trends and factors associated with rhinitis and rhinoconjunctivitis not related to acute infections in New Zealand.

METHODS

The International Study of Asthma and Allergies in Childhood (ISAAC) surveyed children aged 6-7 and 13-14 years for symptoms of these conditions. Five New Zealand centres were surveyed on two occasions (Phase One and Phase Three) 8-10 years apart. In Phase Three, questions were included on environmental factors, which might be associated with rhinoconjunctivitis. We report findings related to symptoms of rhinoconjunctivitis among 24 190 New Zealand children.

RESULTS

Symptoms of rhinoconjunctivitis in the past year were reported in 11.4% of 6- to 7-year-old children and 18% of 13- to 14-year-old adolescents in Phase Three compared with 9.5 and 19.1%, respectively, in Phase One. Severe symptoms of rhinoconjunctivitis were reported in 0.5% of children and 0.8% of adolescents. Current symptoms were more common in males at 6-7 years and in females of 13-14 years, and Māori and Pacific Island ethnic groups had higher prevalence compared with those of European descent, especially in the older age group. For immigrant children, there was a very strong positive relationship between symptoms and length of time resident in New Zealand, supporting the probable importance of environmental factors. A positive association was found between symptoms and use of paracetamol in infancy or in the last year, and weaker associations were noted for antibiotic use, exercise, and regular pasta ingestion.

CONCLUSIONS

Further study of environmental factors is recommended.

The challenges of replicating the methodology between Phases I and III of the ISAAC programme

BACKGROUND

The International Study of Asthma and Allergies in Childhood (ISAAC) used standardised methods to examine symptom prevalence of asthma, rhinitis and eczema in adolescents and children between Phases I and III. Centres followed essential rules to ensure comparability of methodology, examined by a centralised data centre.

METHODS

Centre reports (CRs) were compared for both phases and age groups. Methodological differences were categorised under major deviations (centres excluded), minor deviations (deviations identified in published tables) and very minor deviations (deviations not identified).

RESULTS

There were 112 CRs for adolescents and 70 for children. Six centres for adolescents and four for children had major deviations and were excluded. Minor deviations (35 for adolescents and 20 for children) were identified in the publications. Very minor deviations (92 for adolescents and 51 for children) were not identified. The odds ratios for having any differences in methodology between phases with a change in Principal Investigator were 0.80 (95%CI 0.36-1.81) for adolescents and 0.91 (95%CI 0.32-2.62) for children.

CONCLUSION

The majority of the centres replicated the ISAAC methodology to a high standard. Careful documentation of methodology using standardised tools with careful checks allows the full potential of studies such as ISAAC to be realised.

Serial developmental assessments in infants with deformational plagiocephaly

AIM

An association between positional plagiocephaly and developmental problems has previously been noted, but whether delays persist over time has not been established. This study aimed to determine developmental outcomes for children with deformational plagiocephaly over 1 year of follow up.

METHODS

This was a longitudinal cohort study of 126 infants with deformational plagiocephaly recruited at an outpatient clinic. Development was assessed with the parent-completed Ages and Stages Questionnaires at recruitment and repeated at follow-up assessments in the home 3, 6 and 12 months later. Questionnaires were scored according to cut-off scores from the Ages and Stages Questionnaires, Third Edition.

RESULTS

Ninety-six percent of children were followed up for the full 12 months. The existence of one or more delays initially was 30%; this rose to 42% at the 3-month follow up then dropped back to 23% by the 12-month follow up. Delays were predominantly in the gross motor domain. Ten percent had > 4 delays in total over the four assessments. Mothers with tertiary education were more likely to have infants showing delays that persisted over time.

CONCLUSIONS

Infants with deformational plagiocephaly exhibited marked delays especially in early infancy. These delays were largely gross motor in type but had reduced to approach the expected level by the time of the 12-month follow up, at a mean age of 17 months.

The impact of maternal body mass index on the phenotype of pre-eclampsia: a prospective cohort study

OBJECTIVE

We hypothesised that among nulliparous women with pre-eclampsia, overweight or obese women would have a different phenotype of pre-eclampsia compared with normal weight women with pre-eclampsia. Specifically, they are more likely to develop term pre-eclampsia and less likely to have indicators of impaired placental perfusion, e.g. abnormal uterine artery Doppler or a small-for-gestational-age (SGA) infant.

DESIGN

Prospective, multicentre, cohort SCOPE study (n = 3170).

SETTING

New Zealand and Australia.

POPULATION

Nulliparous women who developed pre-eclampsia.

METHODS

Participants were interviewed at 14-16 weeks of gestation, uterine artery Doppler studies were performed at 19-21 weeks and pregnancy outcome was tracked prospectively.

MAIN OUTCOME MEASURES

Rates of abnormal uterine artery Doppler indices, term/preterm birth and SGA infants were compared between normal, overweight and obese women with pre-eclampsia. Multivariable analysis was performed to examine the association between body mass index (BMI) and term pre-eclampsia.

RESULTS

Of 178 women with pre-eclampsia, one underweight woman was excluded and 66 (37%) were normal weight, 52 (29%) were overweight and 59 (34%) were obese. Pre-eclampsia developed preterm in 26% of women and at term in 74% of women. There were no differences in the rates of term/preterm pre-eclampsia, abnormal uterine artery Doppler indices or SGA infants between BMI groups (P > 0.10). No independent association between BMI and term pre-eclampsia was found (P = 0.56).

CONCLUSIONS

Among women with pre-eclampsia, those who are overweight or obese in early pregnancy are not more likely to have term pre-eclampsia compared with women with a normal BMI. Overweight and obese women require vigilant surveillance for the development of preterm as well as term pre-eclampsia.

Sudden unexpected infant death in Auckland: a retrospective case review

AIM

To review autopsy reports of all SUDI deaths in the Auckland region, New Zealand, from October 2000 to December 2009.

METHODS

Information on all SUDI cases from 2000 to 2009 was extracted from autopsy and police reports from the National Forensic Pathology Service at Auckland Hospital.

RESULTS

Of the 332 post-mortems in this period, 221 were classified as SUDI. Of these, 83% were Māori or Pacific infants. The median age at death was 11 weeks and 11% occurred in 7- to 28-day-olds. At the time of death, 64% overall were bedsharing; this was more common in 7-28 day olds (92%). Bedsharing infants were significantly younger at death than non-bedsharing infants (p=0.008). Where sleep position was known, 57% were placed in non-supine at the last sleep. There was no evidence of diagnostic shift and the prevalence of bedsharing did not change over the decade.

CONCLUSIONS

Bedsharing was associated with a high proportion of SUDI cases, especially in the youngest infants, and non-supine sleep positions were common. There is a need to enhance SUDI prevention messages and consider innovative ways of promoting safe sleeping environment and supine sleep position in Māori and Pacific communities.

Clinical risk prediction for pre-eclampsia in nulliparous women: development of model in international prospective cohort

OBJECTIVES

To develop a predictive model for pre-eclampsia based on clinical risk factors for nulliparous women and to identify a subgroup at increased risk, in whom specialist referral might be indicated.

DESIGN

Prospective multicentre cohort.

SETTING

Five centres in Auckland, New Zealand; Adelaide, Australia; Manchester and London, United Kingdom; and Cork, Republic of Ireland.

PARTICIPANTS

3572 "healthy" nulliparous women with a singleton pregnancy from a large international study; data on pregnancy outcome were available for 3529 (99%).

MAIN OUTCOME MEASURE

Pre-eclampsia defined as ≥ 140 mm Hg or diastolic blood pressure ≥ 90 mm Hg, or both, on at least two occasions four hours apart after 20 weeks' gestation but before the onset of labour, or postpartum, with either proteinuria or any multisystem complication. Preterm pre-eclampsia was defined as women with pre-eclampsia delivered before 37(+0) weeks' gestation. In the stepwise logistic regression the comparison group was women without pre-eclampsia.

RESULTS

Of the 3529 women, 186 (5.3%) developed pre-eclampsia, including 47 (1.3%) with preterm pre-eclampsia. Clinical risk factors at 14-16 weeks' gestation were age, mean arterial blood pressure, body mass index (BMI), family history of pre-eclampsia, family history of coronary heart disease, maternal birth weight, and vaginal bleeding for at least five days. Factors associated with reduced risk were a previous single miscarriage with the same partner, taking at least 12 months to conceive, high intake of fruit, cigarette smoking, and alcohol use in the first trimester. The area under the receiver operating characteristics curve (AUC), under internal validation, was 0.71. Addition of uterine artery Doppler indices did not improve performance (internal validation AUC 0.71). A framework for specialist referral was developed based on a probability of pre-eclampsia generated by the model of at least 15% or an abnormal uterine artery Doppler waveform in a subset of women with single risk factors. Nine per cent of nulliparous women would be referred for a specialist opinion, of whom 21% would develop pre-eclampsia. The relative risk for developing pre-eclampsia and preterm pre-eclampsia in women referred to a specialist compared with standard care was 5.5 and 12.2, respectively.

CONCLUSIONS

The ability to predict pre-eclampsia in healthy nulliparous women using clinical phenotype is modest and requires external validation in other populations. If validated, it could provide a personalised clinical risk profile for nulliparous women to which biomarkers could be added. Trial registration ACTRN12607000551493.

Analysis of factors predicting success of metformin and clomiphene treatment for women with infertility owing to PCOS-related ovulation dysfunction in a randomised controlled trial

BACKGROUND

Metformin has failed to gain wide acceptance as a first-line treatment option for women with anovulatory infertility related to polycystic ovary syndrome. This study aimed to ascertain factors that predict fertility success with treatment that included metformin compared to standard (non-metformin) treatment.

METHODS

Randomised trial data analysis by logistic regression of factors likely to have a differential influence on the likelihood of success of metformin versus non-metformin treatment amongst women with ovulation dysfunction related to polycystic ovary syndrome.

RESULTS

metformin versus those receiving placebo and those with lower BMI who received metformin were more likely to become pregnant than their lower BMI counterparts who received placebo (P=0.039). The subpopulation of women with BMI≤32 kg/m(2) had no factors showing a significantly different impact on the chance of pregnancy for women treated with metformin versus those receiving clomiphene treatment or combination metformin/clomiphene treatment versus clomiphene treatment. There were no significantly different effects of free testosterone, fasting insulin, duration of infertility or ultrasound appearance of polycystic ovaries in any treatment groups.

CONCLUSION

  This study provides preliminary evidence that BMI may be an important prognostic factor in response to metformin for women with ovulation dysfunction related to polycystic ovary syndrome, suggesting that women with a lower BMI may respond better to metformin treatment versus placebo amongst women with BMI>32 kg/m(2) . Individual patient data meta-analysis of existing randomised trials would clarify this further and would assess whether other factors might predict better response to metformin versus standard treatments.

Deformational plagiocephaly: a follow-up of head shape, parental concern and neurodevelopment at ages 3 and 4 years

OBJECTIVES

To compare head shape measurements, parental concern about head shape and developmental delays in infancy with measurements obtained at follow-up at ages 3 and 4 years.

DESIGN

Longitudinal cohort study.

SETTING

Initial assessments were conducted at a plagiocephaly clinic; follow-up assessments were conducted in the children's homes.

PARTICIPANTS

129 children with a mean age of 4 years (range 3 years 3 months to 4 years 9 months), all of whom were diagnosed in infancy with deformational plagiocephaly or brachycephaly.

MAIN OUTCOME MEASURES

Head shape measurements of cephalic index and oblique cranial length ratio; level of parental concern about head shape; and delays on parent-completed age-appropriate Ages and Stages Questionnaires.

RESULTS

61% of head shape measurements reverted to the normal range; 4% remained severe at follow-up. Brachycephaly improved more than plagiocephaly. Facial and frontal asymmetry reduced to almost nil. Most had good improvement, but 13% were categorised as having 'poor improvement'. Initially, 85% of parents reported being 'somewhat' or 'very' concerned; this decreased to 13% at follow-up. The percentage of children with ≥1 delay decreased from 41% initially to 11% at follow-up.

CONCLUSIONS

Overall, head shape measurements, parental concern and developmental delays in infancy showed a dramatic improvement when re-measured at 3 and 4 years of age.

A randomized controlled trial of positioning treatments in infants with positional head shape deformities

BACKGROUND

Randomized controlled trials of treatment for deformational plagiocephaly and brachycephaly have been lacking in the literature.

METHODS

Infants (n = 126) presenting to a plagiocephaly clinic were randomized to either positioning strategies or to positioning plus the use of a Safe T Sleep™ positioning wrap. Head shape was measured using a digital photographic technique, and neck function was assessed. They were followed up at home 3, 6 and 12 months later.

RESULTS

There was no difference in head shape outcomes for the two treatment groups after 12 months of follow-up, with 42% of infants having head shapes in the normal range by that time. Eighty per cent of children showed good improvement. Those that had poor improvement were more likely to have both plagiocephaly and brachycephaly and to have presented later to clinic.

CONCLUSIONS

Most infants improved over the 12-month study period, although the use of a sleep positioning wrap did not increase the rate of improvement.

Acetaminophen use and risk of asthma, rhinoconjunctivitis, and eczema in adolescents: International Study of Asthma and Allergies in Childhood Phase Three

RATIONALE

There is epidemiological evidence that the use of acetaminophen may increase the risk of developing asthma.

OBJECTIVES

To investigate the risk of asthma and other allergic disorders associated with the current use of acetaminophen in 13- to 14-year-old children in different populations worldwide.

METHODS

As part of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three, 13- to 14-year-old children completed written and video questionnaires obtaining data on current symptoms of asthma, rhinoconjunctivitis, and eczema, and a written environmental questionnaire obtaining data on putative risk factors, including acetaminophen use in the past 12 months.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measure was the odds ratio (OR) of current asthma symptoms associated with acetaminophen use calculated by logistic regression. A total of 322,959 adolescent children from 113 centers in 50 countries participated. In the multivariate analyses the recent use of acetaminophen was associated with an exposure-dependent increased risk of current asthma symptoms (OR, 1.43 [95% confidence interval, 1.33-1.53] and 2.51 [95% confidence interval, 2.33-2.70] for medium and high versus no use, respectively). Acetaminophen use was also associated with an exposure-dependent increased risk of current symptoms of rhinoconjunctivitis and eczema.

CONCLUSIONS

Acetaminophen use may represent an important risk factor for the development and/or maintenance of asthma, rhinoconjunctivitis, and eczema in adolescent children.