Associations of physical activity levels and screen time with oral glucose tolerance test profiles in Singaporean women of reproductive age actively trying to conceive: the S-PRESTO study.

AIM: To examine the associations of physical activity and screen time, a proxy for sedentary behaviour, with fasting and post-load glucose levels in Singaporean women enrolled in a multi-ethnic Asian preconception study. METHODS: Moderate and vigorous physical activity and screen time (television and other electronic devices) were self-reported by women enrolled in the S-PRESTO cohort. Fasting, 30-min and 120-min glucose levels before and during a 75-g oral glucose tolerance test were measured. Associations of physical activity and screen time with glucose levels were analysed using multivariable linear marginal regression. RESULTS: A total of 946 women aged 31.4±3.7 years were examined, of whom 72% were of Chinese, 15.5% were of Malay, 9.3% were of Indian and 3.2% were of mixed ethnicity. A total of 32% of women reported being active, 36% watched television ≥2 h/day and 26% used electronic devices ≥3 h/day. In adjusted models, vigorous, but not moderate, physical activity was associated with lower overall glucose levels, and was associated more strongly with post-challenge than fasting glucose levels. Compared to women not engaging in vigorous physical activity, those engaging in physical activity ≥75 min/week had lower mean fasting [-0.14 (95% CI -0.28, -0.01) mmol/l], 30-min [0.35 (95% CI -0.68, -0.02) mmol/l] and 120-min [-0.53 (95% CI -0.16, -0.90) mmol/l] glucose levels (overall P value=0.05). We found no associations of screen time with glucose levels. CONCLUSIONS: Independently of the time spent in non-vigorous physical activity and using screens, engaging in vigorous physical activity may be a modifiable factor to improve glucose regulation in women of Asian ethnicity who are attempting to conceive.

Female adiposity and time-to-pregnancy: a multiethnic prospective cohort.

STUDY QUESTION: Are higher overall and central adiposity associated with reduced fecundability, measured by time-to-pregnancy (TTP), in Asian women? SUMMARY ANSWER: Higher overall adiposity, but not central adiposity, was associated with longer TTP in Asian women. WHAT IS KNOWN ALREADY: High body mass index (BMI) has been associated with a longer TTP, although the associations of body composition and distribution with TTP are less clear. There are no previous studies of TTP in Asian women, who have a relatively higher percentage of body fat and abdominal fat at relatively lower BMI. STUDY DESIGN, SIZE, DURATION: Prospective preconception cohort using data from 477 Asian (Chinese, Malay and Indian) women who were planning to conceive and enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO) study, 2015-2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women's mean age was 30.7 years. Overall adiposity was assessed by BMI, sum of 4-site skinfold thicknesses (SFT) and total body fat percentage (TBF%, measured using air displacement plethysmography); central adiposity was assessed by waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and A body Shape Index (ABSI). Pregnancy occurring within one year from recruitment was ascertained by ultrasonography. Those who did not conceive within one year of recruitment, were lost to follow-up, or initiated fertility treatment were censored. TTP was measured in cycles. Discrete-time proportional hazards models were used to estimate the fecundability ratio (FR) and 95% confidence interval (CI) for each anthropometric measure in association with fecundability, adjusting for confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to women with a normal BMI of 18.5-22.9 kg/m2, women with higher BMI of 23-27.4 and ≥27.5 kg/m2 showed lower FR of 0.66 (95% CI 0.45, 0.97) and 0.53 (0.31, 0.89), respectively. Compared to women in the lowest quartile of SFT (25-52.9 mm), those in the highest quartile of ≥90.1 mm showed lower FR of 0.58 (95% CI 0.36, 0.95). Compared to women in the lowest quartile of TBF% (13.6-27.2%), those in the upper two quartiles of 33.0-39.7% and ≥39.8% showed lower FR of 0.56 (95% CI 0.32, 0.98) and 0.43 (0.24, 0.80), respectively. Association of high BMI with reduced fecundability was particularly evident among nulliparous women. Measures of central adiposity (WC, WHR, WHtR, ABSI) were not associated with fecundability. LIMITATIONS REASONS FOR CAUTION: Small sample size could restrict power of analysis.The analysis was confined to planned pregnancies, which could limit generalizability of findings to non-planned pregnancies, estimated at around 44% in Singapore. Information on the date of last menstrual period for each month was not available, hence the accuracy of self-reported menstrual cycle length could not be validated, potentially introducing error into TTP estimation. Measures of exposures and covariates such as cycle length were not performed repeatedly over time; cycle length might have changed during the period before getting pregnant. WIDER IMPLICATIONS OF THE FINDINGS: Other than using BMI as the surrogate measure of body fat, we provide additional evidence showing that higher amounts of subcutaneous fat that based on the measure of SFT at the sites of biceps, triceps, suprailiac and subscapular, and TBF% are associated with longer TTP. Achieving optimal weight and reducing total percentage body fat may be a potential intervention target to improve female fertility. The null results observed between central adiposity and TTP requires confirmation in further studies. STUDY FUNDING/COMPETING INTEREST(S): This research is supported by Singapore National Research Foundation under its Translational and Clinical Research Flagship Programme and administered by the Singapore Ministry of Health's National Medical Research Council, (NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014). Additional funding is provided by the Singapore Institute for Clinical Sciences, Agency for Science Technology and Research (A*STAR), Singapore. Y.S.C., K.M.G., F.Y. and Y.S.L. have received reimbursement to speak at conferences sponsored by companies selling nutritional products. Y.S.C., K.M.G. and S.Y.C. are part of an academic consortium that has received research funding from Abbott, Nutrition, Nestle and Danone. Other authors declared no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Characteristics associated with the consumption of malted drinks among Malaysian primary school children: findings from the MyBreakfast study.

BACKGROUND: The consumption of beverages contributes to diet quality and overall nutrition. Studies on malted drinks, one of the widely consumed beverage choices among children in Asia, however, have received limited attention. This study aimed to examine the prevalence of malted drink consumption and explored associations of sociodemographic characteristics, nutrient intakes, weight status and physical activity levels with malted drink consumption among primary school children in Malaysia. METHODS: Data for this analysis were from the MyBreakfast Study, a national cross-sectional study conducted from April to October 2013 throughout all regions in Malaysia. A total of 2065 primary school children aged 6 to 12 years were included in the present analysis. Data on two days 24-h dietary recall or record, anthropometry, physical activity and screen time were recorded. Associations between malted drink consumption and related factors were examined using binary logistic regression, adjusting for region, area, gender, ethnicity and household income. RESULTS: Among children aged 6 to 12 years, 73.5% reported consuming malted drinks for at least once per week. Consumption of malted drinks was significantly associated with region (χ(2) = 45.64, p < 0.001), gender (χ(2) = 4.41, p = 0.036) and ethnicity (χ(2) = 13.74, p = 0.008). Malted drink consumers had similar total energy intake but higher micronutrient intakes compared to non-consumers. High physical activity level (OR = 1.77, 95% CI = 1.06, 2.99) and lower screen time during weekends (OR = 0.93, 95% CI = 0.86, 0.99) were independently associated with malted drink consumption among 6 to 9 year-old children, but not among 10 to 12 year-old children. No association was observed between malted drink consumption and weight status. CONCLUSIONS: Malted drink consumption is prevalent among Malaysian primary school children, particularly higher among boys, indigenous children and those who lived in the East Coast region of Malaysia. Consuming malted drinks is associated with higher micronutrient intakes and higher levels of physical activity, but not with body weight status.

The effects of prenatal oxidative stress levels on infant adiposity development during the first year of life.

Although numerous studies have been conducted to examine the causal factors of childhood obesity, the implications of intrauterine oxidative stress on early postnatal adiposity development remain to be elucidated. The Universiti Sains Malaysia Birth Cohort Study aimed to investigate the effects of prenatal oxidative stress levels on the development of infant adiposity during the first year of life. This study was conducted on the healthy pregnant women aged 19-40 years, from April 2010 to December 2012 in Kelantan, Malaysia. Maternal blood samples were drawn in the second trimester to analyse for oxidative stress markers. Infant anthropometric measurements were taken at birth, 2, 6 and 12 months of age. A total of 153 pregnant women and full-term infants were included in the analysis. Statistical test was conducted by using multiple linear regression. Through the infant first year of life, as maternal DNA damage level in the second trimester increased, infant weights at birth (ß=-0.122, P<0.001), 2 months (ß=-0.120, P=0013), 6 months (ß=-0.209, P=0.003) and 12 months of age (ß=-0.241, P=0.006) decreased after adjusting for confounders. Similar results were noted when infant body mass index-for-age Z-scores and triceps skinfold-for-age Z-scores were used as the adiposity indicators. In conclusion, the present study shows a consistent inverse association between maternal DNA damage and infant adiposity during the first year of life. These infants with reduced growth and adiposity in early postnatal life may have a high tendency to experience catch-up growth during childhood, which could be strongly associated with later obesity.

Development, validity and reproducibility of a food frequency questionnaire in pregnancy for the Universiti Sains Malaysia birth cohort study.

INTRODUCTION: This study aimed to develop and examine the validity and reproducibility of a semi-quantitative food frequency questionnaire (FFQ) among Malay pregnant women in Kelantan, Malaysia. METHODS: A total of 177 Malay pregnant women participated in the validation study while 85 of them participated in the reproducibility study which was carried out in the antenatal clinic of Universiti Sains Malaysia Hospital. The newly developed FFQ was validated against two 24-hour dietary recalls (DR). The FFQ was repeated 20 to 28 days apart. RESULTS: Results showed that the FFQ moderately over-estimated the nutrient and food intakes compared to the DR. Spearman correlation coefficients for nutrients ranged from 0.24 (fat) to 0.61 (calcium) and for foods, ranged from 0.13 (organ meats, onion and garlic) to 0.57 (malt drink). For nutrients, 72 to 85% of women were classified into the correct quartiles from the FFQ and the DR while for foods, 67 to 85% of women were classified correctly. Bland-Altman plot showed relatively good agreement between these two dietary methods. The intra-class correlation (ICC) was used to estimate reproducibility. It ranged from 0.75 (vitamin C) to 0.94 (phosphorus) for nutrients while it ranged from 0.73 (confectionary) to 0.96 (coffee) for foods. CONCLUSION: On average, at least 90% of pregnant women were correctly classified into the quartiles for nutrients and foods from the two sets of the FFQ. The FFQ presented acceptable reproducibility and appears to be a valid tool for categorising pregnant women according to dietary intake.