Nutritional Epidemiology of Antenatal Smoking Cessation Among Japanese Women.

This study compared the nutritional status before pregnancy, as well as dietary profiles and biomarkers during first trimester, between never-smokers and antenatal quitters among Japanese women. One hundred fifty pregnant women (79 never-smokers and 71 antenatal quitters) from two obstetrics and gynecology clinics were recruited in Japan. Subjects' prepregnancy nutritional status was indicated by their body mass index (BMI). In the first trimester, their dietary profiles were assessed by the Brief Diet-History Questionnaire (BDHQ) and pregnancy outcomes were screened by biomarker tests. Generalized linear regression was used to examine the differences of energy-adjusted dietary intakes and biomarker results between the two smoking groups, with adjustment of maternal age, BMI, gestation week, and parity. The results showed that antenatal quitters were more likely to have a prepregnancy underweight status than never-smokers. During the first trimester, antenatal quitters had significantly higher intakes of unsaturated fatty acids and antioxidants (vegetable lipids and isoflavone), and lower intakes of total cholesterol than never-smokers. Moreover, antenatal quitters had a significantly higher level of serum homocysteine (6.36 nmol/mL vs 4.88 nmol/mL) than never-smokers. In conclusion, antenatal quitters are more likely to have a poor nutritional status before pregnancy than never-smokers. Quitting smoking before pregnancy and having a good nutritional profile during the trimester may not sufficiently reverse the adverse effects of former smoking behaviors on pregnancy outcomes.

Measurement Invariance of the Internet Addiction Test Among Hong Kong, Japanese, and Malaysian Adolescents.

There has been increased research examining the psychometric properties on the Internet Addiction Test (IAT) in different populations. This population-based study examined the psychometric properties and measurement invariance of the IAT in adolescents from three Asian countries. In the Asian Adolescent Risk Behavior Survey (AARBS), 2,535 secondary school students (55.9% girls) aged 12-18 years from Hong Kong (n=844), Japan (n=744), and Malaysia (n=947) completed a survey in 2012-2013 school year. A nested hierarchy of hypotheses concerning the IAT cross-country invariance was tested using multigroup confirmatory factor analyses. Replicating past findings in Hong Kong adolescents, the construct of the IAT is best represented by a second-order three-factor structure in Malaysian and Japanese adolescents. Configural, metric, scalar, and partial strict factorial invariance was established across the three samples. No cross-country differences on Internet addiction were detected at the latent mean level. This study provided empirical support for the IAT as a reliable and factorially stable instrument, and valid to be used across Asian adolescent populations.

Impact of dietary folate intake on depressive symptoms in young women of reproductive age.

INTRODUCTION: Folate deficiencies may be linked to depressive disorders among persons suffering from neurological and psychiatric problems. The purpose of the present study was to evaluate the impact of dietary folate intake on depressive symptoms in young Japanese women of reproductive age. METHODS: The study was conducted in Japan in 2009 with 141 Japanese women aged 18 to 28 years. A Japanese version of the Center for Epidemiologic Studies Depression (CES-D) scale was used to screen for depressive symptoms. Dietary intake was investigated by a diet history questionnaire. Nonfasting blood samples were collected from the women to measure folate and homocysteine levels. RESULTS: The proportion of women with lower folate intake (< 240 µg/d) was significantly higher in the women with CES-D scores greater than or equal to 19 when compared with the folate levels in those with CES-D scores less than 19 (75.0% vs 43.6%, respectively; P < .001). Logistic regression analysis revealed significant associations between CES-D scores greater than or equal to 19, low folate intake, and low vitamin B(6) intake when adjusted for age, living status, smoking, and body mass index. Adequate folate intake of more than the recommended dietary allowance (RDA) level of 240 µg per day was independently related to a decreased risk of depression (adjusted odds ratio 0.22; 95% confidence interval, 0.11-0.56; P < .001). DISCUSSION: Multiple logistic regression analysis revealed a reduced incidence of depression in women whose intake of folate exceeded the RDA of 240 µg per day. This finding suggests that dietary folate intake may be causally related to depressive symptoms in women of reproductive age. If results of studies powered to determine causal relationships are similarly positive, folate supplementation could reduce the incidence of depression.