Mediation effect of sleep time on the association between outdoor activity and myopia in Chinese children and adolescents: a cross-sectional study.

BACKGROUND: This study aimed to assess the association between outdoor activity and myopia among children and adolescents and investigate whether sleep time could mediate this relationship. METHODS: This cross-sectional study was performed on students aged 4-16 years in China, from August 2021 to January 2022. Outdoor activity was assessed by the Assessment Questionnaire of Exposure to Sunlight Activities for Students (AQESAS). Binary logistic regression combined with the mediation analysis was used to analyze the association of AQESAS with myopia and the mediating effect of sleep time on this relationship. RESULTS: The prevalence of myopia was 53.51% (N = 1609). Multivariate logistic regression analysis showed that more sleep time (OR = 0.794, 95%CI: 0.707-0.893) and a higher score of AQESAS (OR = 0.989, 95%CI: 0.981-0.996) were significantly associated with a decreased risk of myopia. Mediation analysis revealed that sleep time plays a mediating role in the association between outdoor activity and myopia (ACME = -0.0006, P < 0.001), and the mediation proportion was 19.7%. CONCLUSION: Outdoor activity affects myopia directly and indirectly through sleep time. The result suggested that children may be able to reduce the risk of myopia by promoting sleep through increased awareness of outdoor activity and exposure to sunlight.

Effects of the Chinese Heart-Healthy Diet (Sichuan Cuisine Version) on the 10-year CVD risk and vascular age: a randomised controlled feeding trial.

Sichuan cuisine was previously fitted into the Chinese Heart-Healthy Diet (CHH) trial to verify the antihypertensive effect. Whether the modified Sichuan diet lessens cardiovascular disease (CVD) is not fully explored. We aimed to estimate the effects of the Sichuan version of CHH diet (CHH diet-SC) on the 10-year risk of CVD and vascular age. A single-blinded randomised controlled feeding trial was conducted. General CVD prediction model was used in manners of intention-to-treat and per-protocol set. After a 7-d run-in period, fifty-three participants with pre- and grade I hypertension from local communities were randomised and provided with either CHH diet-SC (n 27) or a control diet (n 26) for 4 weeks. Mean absolute and relative estimated CVD risks were reduced by 4·5 % and 27·9 % in the CHH diet-SC group, and the between-group relative risk reduction was 19·5 % (P < 0·001) using linear mixed-effects models. The sensitivity analysis with datasets and models showed consistent results, and pre-specified factors were not associated with the intervention effects. The vascular age of CHH-SC group was theoretically 4·4 years younger than that of the control group after intervention. Compared with a typical diet, adopting the CHH diet-SC over 1 month significantly reduced 10-year CVD risks and vascular ages among local adults with mild hypertension.

[Evaluation of calcium intake levels and sources among pregnant women in a Chengdu hospital in 2017].

OBJECTIVE: Investigate and evaluate the levels and sources of calcium intake of pregnant women in Chengdu during three trimesters. METHODS: Use the data of a cohort study in Chengdu in 2017. The healthy singleton pregnant women with 8-14 weeks of pregnancy in an obstetrical clinic of a maternal-and-child health care institution in Chengdu were selected as the object of the study. Data on maternal demographic characteristics and the use information of calcium supplements in the past month of each trimester were collected by questionnaire investigation. The dietary intakes data of pregnant women in each trimester was collected by the 3-day 24-hour dietary recall method. The dietary calcium intake and the contribution of calcium from different foods were calculated based on the Chinese Food Composition Table(2018). The total calcium intake was obtained by adding the dietary calcium and supplement calcium intake. The calcium intake was evaluated with reference to the Chinese Dietary Nutrient Reference Intakes(2013). RESULTS: Valid samples of 1653 cases in early pregnancy, 1024 cases in middle pregnancy and 1017 cases in late pregnancy were finally included. The median intake of total calcium was 523.3, 1280.5 and 1491.3 mg/d in three trimesters, respectively. The adequate rate of total calcium intake was 16.3%, 63.2% and 67.1%, the insufficient rate was 69.0%, 15.7% and 11.2%, the excess rate was 0.2%, 9.1% and 14.4%, respectively. The median intake of dietary calcium was 453.0, 613.0 and 723.0 mg/d in three trimesters respectively. The dietary calcium adequate rates were 7.1%, 9.7% and 16.2%, the dietary calcium deficiency rates were 82.0%, 75.0%, 62.6%, respectively. The main food sources of dietary calcium in each pregnancy were dairy foods, vegetables, tubers and grains. The contribution of dairy foods to the dietary calcium was 33.8%, 37.7% and 40.2%, respectively. The median intake of milk was 125.0, 235.3 and 250.0 g/d, respectively. Among all pregnant women, the calcium supplement use in three trimesters was 36.2%, 93.4% and 91.7%, respectively; the median intake of supplement calcium was 0.0, 625.0 and 750.0 mg/d, respectively. Among pregnant women who met the dietary calcium standard, the use of calcium supplements in the three trimesters was 38.1%, 95.0% and 94.5%, respectively; the median intake of supplemental calcium was 0.0, 725.0 and 750.0 mg/d, respectively. CONCLUSION: The insufficient and excessive total calcium intake coexisted among pregnant women in Chengdu, with the insufficient dietary calcium intake prominent in all trimesters. The use of calcium supplements was common in middle and late pregnancy.

Healthier diet associated with reduced risk of excessive gestational weight gain: A Chinese prospective cohort study.

Limited studies have examined the associations between diet quality and gestational weight gain (GWG) among Chinese pregnant women, adopting Chinese GWG guidelines. We prospectively investigate the associations of diet quality, using the Chinese Healthy Diet Index for Pregnancy (CHDI-P), which assessed diet quality from 'Diversity', 'Adequacy' and 'Limitation' dimensions with overall 100 points, with GWG among participants enroled in Southwest China. Food consumption was collected by 24 h dietary recalls for three consecutive days and CHDI-P scores were divided into tertiles. GWG was calculated according to the weight measured before delivery and classified into adequate weight gain (AWG), insufficient weight gain (IWG) and excessive weight gain(EWG) following Chinese GWG guidelines. Multinomial regression analyses and stratified analyses by pre-pregnancy body mass index were performed to estimate the association between CHDI-P and GWG. A total of 1416 participants were recruited in early pregnancy, and 971 and 997 participants were respectively followed up in middle and late pregnancy. The mean CHDI-P score was 56.44 ± 6.74, 57.07 ± 7.44 and 57.38 ± 7.94 points in early, middle and late pregnancy, respectively. Women in the lowest CHDI-P scores group had an increased risk of EWG in middle (OR = 1.53, 95% confidence interval [CI] = 1.08-2.17) and late pregnancy (OR = 1.71, 95% CI = 1.21-2.41) than women in the highest group, while overweight/obese women had a greater risk of EWG in late pregnancy (OR = 4.25, 95% CI = 1.30-13.90). No association was found between the CHDI-P scores and IWG. Poor diet quality in middle and late pregnancy was associated with a higher risk of EWG.

Dietary fat quantity and quality in early pregnancy and risk of gestational diabetes mellitus in Chinese women: a prospective cohort study.

We aimed to examine the association between the quantity and quality of dietary fat in early pregnancy and gestational diabetes mellitus (GDM) risk. In total, 1477 singleton pregnant women were included from Sichuan Provincial Hospital for Women and Children, Southwest China. Dietary information was collected by a 3-d 24-h dietary recall. GDM was diagnosed based on the results of a 75-g, 2-h oral glucose tolerance test at 24-28 gestational weeks. Log-binomial models were used to estimate relative risks (RR) and 95% CI. The results showed that total fat intake was positively associated with GDM risk (Q4 v. Q1: RR = 1·40; 95 % CI 1·11, 1·76; Ptrend = 0·001). This association was also observed for the intakes of animal fat and vegetable fat. After stratified by total fat intake (< 30 %E v. ≥ 30 %E), the higher animal fat intake was associated with higher GDM risk in the high-fat group, but the moderate animal fat intake was associated with reduced risk of GDM (T2 v. T1: RR = 0·65; 95 % CI 0·45, 0·96) in the normal-fat group. Vegetable fat intake was positively associated with GDM risk in the high-fat group but not in the normal-fat group. No association between fatty acids intakes and GDM risk was found. In conclusion, total fat, animal and vegetable fat intakes were positively associated with GDM risk, respectively. Whereas when total fat intake was not excessive, higher intakes of animal and vegetable fat were likely irrelevant with increased GDM risk, even the moderate animal fat intake could be linked to lower GDM risk.

[Intakes and sources of fat and fatty acids among pregnant women in Chengdu in 2017: a longitudinal study].

OBJECTIVE: To analyze the intake of fat and fatty acids and their food sources of pregnant women in Chengdu. METHODS: Participants were from a cohort study in 2017, which was conducted among 1652 healthy singleton pregnant women within 6-14 weeks of gestation in a maternity out-patient clinic of maternal-and-child health care institution in Chengdu, Sichuan Province. Data on maternal demographic characteristics was collected by questionnaire. In three trimesters, 3-day 24-hour dietary recall method was applied to collect dietary intakes data, with the information of docosahexaenoic acid(DHA) supplement intake being collected by questionnaire. The intakes and sources of daily fat and fatty acids in three trimesters were calculated using the National Nutrient Database of USDA and China Food Composition Tables(6th edition). The intake levels of fat and fatty acids were evaluated according to 2013 Chinese Dietary Reference Intakes. RESULTS: The study showed that the intakes of total fat and fatty acids increased during pregnancy. The mean intake of total daily fat was 64.8 g/d, 81.2 g/d, 88.5 g/d in three trimesters, respectively. The proportion of energy from total fat >30%E during three trimesters were 67.7%, 77.6%, 82.9%, respectively. The proportions of energy from saturated fatty acids(SFA) were 7.9%E, 8.9%E, 9.7%E, and those higher than 10%E were 20.9%, 31.9%, 44.7% in three trimesters, respectively. The proportions of energy from monounsaturated fatty acids(MUFA) were 12.9%E, 13.5%E, 14.2%E, and the proportions of energy from polyunsaturated fatty acids(PUFA) were 8.5%E, 8.4%E, 8.8%E in three trimesters, respectively. The proportion of DHA intake meeting recommendation(200 mg/d) in three trimesters were 3.6%, 21.7%, 21.1%, respectively. The radio of SFA, MUFA and PUFA(S∶M∶P) was 1∶1.6∶1.1 in the early trimester, and S∶M∶P was 1∶1.5∶1 in the second trimester and third trimester. Total fat and MUFA mainly came from edible oil and meat, and PUFA mainly came from edible oil and nuts. SFA mainly came from meat and milk, and the contribution of milk to SFA increased during pregnancy. CONCLUSION: The excessive intakes of total fat and SFA and the inadequate intake of DHA among pregnant women in Chengdu deserve attention.

Associations of Exposure to Air Pollution with Insulin Resistance: A Systematic Review and Meta-Analysis.

In this article, we review the available evidence and explore the association between air pollution and insulin resistance (IR) using meta-analytic techniques. Cohort studies published before January 2018 were selected through English-language literature searches in nine databases. Six cohort studies were included in our sample, which assessed air pollutants including PM2.5 (particulate matter with an aerodynamic diameter less than or equal to 2.5 µm), NO2(nitrogen dioxide), and PM10 (particulate matter with an aerodynamic diameter less than 10 µm). Percentage change in insulin or insulin resistance associated with air pollutants with corresponding 95% confidence interval (CI) was used to evaluate the risk. A pooled effect (percentage change) was observed, with a 1 µg/m³ increase in NO2 associated with a significant 1.25% change (95% CI: 0.67, 1.84; I² = 0.00%, p = 0.07) in the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and a 0.60% change (95% CI: 0.17, 1.03; I² = 30.94%, p = 0.27) in insulin. Similar to the analysis of NO2, a 1 µg/m³ increase in PM10 was associated with a significant 2.77% change (95% CI: 0.67, 4.87; I² = 94.98%, p < 0.0001) in HOMA-IR and a 2.75% change in insulin (95% CI: 0.45, 5.04; I² = 58.66%, p = 0.057). No significant associations were found between PM2.5 and insulin resistance biomarkers. We conclude that increased exposure to air pollution can lead to insulin resistance, further leading to diabetes and cardiometabolic diseases. Clinicians should consider the environmental exposure of patients when making screening and treatment decisions for them.