Omega-3 fatty acid intake during pregnancy and risk of infant maltreatment: a nationwide birth cohort - the Japan Environment and Children's Study

Decision tree learning for predicting chronic postpartum depression in the Japan Environment and Children's Study

BACKGROUND

Many studies have used machine learning techniques to construct predictive models of postpartum depression, but few such models are simple enough to use in community maternal health settings with pen and paper. Here, we use a decision tree to construct a prediction model for chronic postpartum depression.

METHODS

Participants were 84,091 mothers. Chronic postpartum depression was identified as an Edinburgh Postnatal Depression Scale score of ≥9 at both 1 and 6 months postpartum. The training dataset included 84 diverse variables measured during pregnancy, including health status and biomarkers. In learning, the branching depth was constrained to 3, the number of branches per branch to 4, and the minimum number of n in a branch was 100. The training to validation data ratio was set to 7:3.

RESULTS

A decision tree with 35 branches and an area under the receiver operating characteristic of 0.84 was created. Ten of 84 variables were extracted, and the most effective in classification was "feeling worthless." At training (n = 58,635), the most and least prevalent branches were 73.2 % and 0.84 % (mean = 6.29 %), respectively; at validation (n = 25,456), they were 60.4 % and 0.72 % (mean = 6.52 %), respectively.

LIMITATIONS

Chronic postpartum depression was identified using self-administered questionnaires.

CONCLUSIONS

This study created a simple and relatively high-performing prediction model. Because the model can be easily understood and used without expertise in machine learning, it is expected to be useful in maternal health settings, including grassroots community health.

Nutritional factors associated with aggression

Although the vast majority of patients in forensic psychiatry are treated using pharmacological agents, clinical and ethical concerns about their use have led to the consideration of alternative strategies to reduce aggression that is common in forensic psychiatric settings. One non-invasive and benign biologically-based treatment approach involves nutrition. This article provides a mini-review of the recent evidence on four salient nutritional factors associated with aggressive behavior, namely omega-3 fatty acids, vitamin D, magnesium, and zinc. The current evidence base indicates that lower omega-3 levels are associated with increased aggression. Although research on vitamin D and zinc in relation to aggressive behavior is more limited, there is initial evidence that they are negatively associated with aggression in healthy participants and in psychiatric samples. The relationship between magnesium and aggression varies depending on how magnesium is assessed. Findings from experimental trials reveal that nutritional intervention in the form of omega-3 supplementation has the potential to serve as an effective mode of treatment, with effects that can last beyond the intervention period. There is also support for the utility of nutrition to improve our understanding of how social processes are linked to aggression. In light of the nascent, but promising findings on the role of nutritional factors on aggressive behavior, directions for future research are discussed.

Association of infants' feeding pattern up to 2 years postpartum with mothers' mental and physical health: the Japan Environment and Children's Study

BACKGROUND

Exclusive breastfeeding, a longer breastfeeding duration, and interaction with the baby during lactation improve mothers' mental health. However, few studies have targeted women around 2.5 years after childbirth, when women are still considered to have been in a period of mental and physical health vulnerability. This study examined this aspect in a large cohort of mother-child pairs.

METHODS

Data were obtained from 85,735 mothers in an ongoing nationwide birth cohort study in Japan. Exposures were exclusive breastfeeding (yes/no), continued breastfeeding up to 2 years (yes/no), and interaction with the baby during feeding (yes/no). Outcomes were mothers' mental and physical health 2.5 years after childbirth measured using Mental and Physical Component Summary scores (MCS and PCS scores, respectively) from the 8-item Short-Form Health Survey. Generalized additive mixed model analysis was used to derive each estimate for the three exposures and their interactions, with each "no" answer as reference.

RESULTS

Exclusive breastfeeding and interaction with the baby during feeding were associated with MCS score increases of 0.28 (95%CI: 0.10-0.47) and 0.41 (95%CI: 0.29-0.54), respectively. However, no associations were found for continued breastfeeding up to 2 years and no interactions were identified. No significant differences were observed for PCS scores.

LIMITATIONS

All variables were measured using a self-administered questionnaire.

CONCLUSIONS

Continued exclusive breastfeeding until 6 months and interaction with the baby during feeding may help to promote mother's mental health 2.5 years after childbirth. These findings further strengthen the rationale for the World Health Organization's recommended lactation practices.

Cesarean section and parenting stress: Results from the Japan Environment and Children's Study

BACKGROUND

Accumulating evidence suggests a long-term health risk of cesarean section for the mother and child, but few studies have examined the link between cesarean section and parenting stress. Here, we examined this association by exploiting a large dataset.

METHODS

Participants were 65,235 mothers participating in the Japan Environment and Children's Study, an ongoing nationwide birth cohort. Outcome variables were parenting stress assessed as total score and subscale scores (representing the difficult child, parental distress, and spouse factors) on the Japanese 19-item version of the Parenting Stress Index Short Form (J-PSI-SF). Exposures were the mode of delivery, the timing of the J-PSI-SF assessment (1.5, 2.5, and 3.5 years postpartum), and the interaction between them. Multivariate regression analysis was used to calculate adjusted β coefficients and standard error of the means (SEMs).

RESULTS

The J-PSI-SF total score was higher in the cesarean section group than in the vaginal delivery group (adjusted β = 0.24, SEM = 0.09). This increase was primarily due to higher scores for the difficult child factor (adjusted β = 0.18, SEM = 0.05) and not to higher scores for the parental distress or spouse factor.

CONCLUSIONS

Cesarean section was associated with higher parenting stress, especially in relation to the difficult child factor. Our results highlight the importance of paying particular attention to the mental health of both mother and child in the case of cesarean section.

Dietary intake of yogurt and cheese in children at age 1 year and sleep duration at age 1 and 3 years: the Japan Environment and Children's Study

Background

We previously reported that 1-year-old infants born to mothers who regularly consumed fermented food during pregnancy had a lower risk of sleep deprivation. However, it is not known if these positive effects are enhanced when infants themselves eat fermented foods or the long-term effects of such consumption. In this study, we examined the association between the frequency of fermented food intake during the child’s weaning period and sleep deprivation at age 1 and 3 years.

Methods

This birth cohort study used data from a nationwide, government-funded study called the Japan Environment and Children’s Study (JECS), covering 65,210 mother-child pairs. We examined the association between infants’ consumption of fermented foods at 1 year of age and sleep deprivation at 1 and 3 years of age.

Results

There was no association between yogurt or cheese intake and sleep duration at age 1; at age 3, there was no group difference, although a trend test showed that yogurt intake at age 1 was significantly associated with sleep duration at age 3. There was also no association between the frequency of cheese intake and inadequate sleep duration at age 3.

Conclusion

Frequency of children’s yogurt and cheese intake at age 1 was not associated with sleep duration at age 1 or 3. However, a trend test showed a significant association between the frequency of yogurt intake at age 1 and sleep duration at age 3.

Association between maternal fermented food consumption and child sleep duration at the age of 3 years: the Japan Environment and Children's Study

Background

Using cohort data from the Japan Environment and Children’s Study (JECS), we previously reported that the risk of sleep deprivation in 1-year-old children was reduced with a higher maternal intake of fermented foods, particularly miso. The present study, which evaluates children from the same cohort at 3 years of age, is a continuation of that work.

Methods

After applying exclusion criteria to 104,062 records in the JECS dataset, we evaluated 64,200 mother-child pairs in which the child was 3 years old. We examined the association of the dietary intake of fermented foods during pregnancy with child sleep duration < 10 h at the age of 3 years.

Results

Multivariable logistic regression analysis with the lowest quartile used as a reference revealed adjusted odds ratios (95% confidence intervals) for the second through fourth quartiles of 0.98 (0.90–1.06), 0.93 (0.85–1.01), and 0.85 (0.78–0.94) for cheese intake.

Conclusions

The consumption of fermented foods during pregnancy is associated with reduced risk of sleep deprivation in 3-year-old children, albeit in a limited way.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13805-6.

Male intake of omega-3 fatty acids and risk of intimate partner violence perpetration: a nationwide birth cohort - the Japan Environment and Children's Study

AIMS

Intake of omega-3 polyunsaturated fatty acids (PUFAs) has favourable effects on reducing aggressive and violent behaviours, but its association with perpetration of intimate partner violence (IPV) is not known. We aimed to determine the association between male intake of omega-3 PUFAs and risk of IPV perpetration.

METHODS

Participants were male-female pairs in the Japan Environment and Children's Study, in which first pregnant women and then their partners were enrolled (analytic sample: n = 48 065). Male intake of omega-3 PUFAs during the past year (preconception to mid/late pregnancy) was determined using a food frequency questionnaire. IPV (physical violence and emotional abuse) during pregnancy was measured using a self-reported questionnaire completed by pregnant women in mid/late pregnancy. Generalised additive mixed-model analysis was used to examine the non-linear association between energy-adjusted male omega-3 PUFA intake and the adjusted prevalence of male IPV perpetration.

RESULTS

A sharply decreasing regression curve was plotted for physical violence, with prevalence starting at 1.35% at the lowest intake level and decreasing to a minimum value of 0.76% at intake of 2.20 g/day (71.7th percentile). However, prevalence largely remained flat from there onward, with the upper limit of the error range not reaching the initial lower limit of the error range until intake exceeded 5.21 g/day (99.77th percentile). For emotional abuse, on the other hand, there was a distorted U- or V-shaped regression curve that rose slightly after reaching a minimum. The prevalence declined from 17.69% initially, reached a minimum at 12.44% at 2.13 g/day (68.3th percentile), and then rose slightly. The lower limit of the error range reached the minimum upper limit at 4.17 g/day (99.1th percentile), and the upper limit finally reached the maximum lower limit value at 4.56 g/day (99.5th percentile).

CONCLUSIONS

In this nationwide birth cohort study, higher male intake of omega-3 PUFAs was associated with lower risk of physical violence and emotional abuse perpetration except for extremely high intake. Our results indicate the potential applicability of omega-3 PUFAs in reducing aggressive and violent behaviours in IPV.Trial registration: UMIN000030786.

Causal model of the association of social support during pregnancy with a perinatal and postpartum depressive state: A nationwide birth cohort - the Japan Environment and Children's Study

BACKGROUND

Despite many epidemiological studies on the relationship between social support during pregnancy and perinatal/postpartum depression, its impact remains unclear. Therefore, this study examined this association using a causal model of risk based on various levels of social support.

METHODS

Participants were 88,711 mothers in an ongoing nationwide birth cohort study in Japan. Social support during pregnancy was set at four treatment levels. Depressive state was identified twice, with the Kessler Psychological Distress Scale (K6; score ≥ 5) and the Edinburgh Postnatal Depression Scale (EPDS; score ≥ 9). With the highest level of social support set as reference, marginal structural models were fitted to derive counterfactual risk ratios (cRRs).

RESULTS

cRRs (95% CIs) for EPDS cases increased as the level of social support decreased, with values of 1.06 (0.99-1.13) for upper-middle, 1.30 (1.23-1.39) for lower-middle, and 1.61 (1.52-1.71) for low. Also, cRRs (95% CIs) at the second measurement (interaction) tended to increase as social support decreased, with values of 1.05 (0.97-1.13) for upper-middle, 1.05 (0.98-1.13) for lower-middle, and 1.10 (1.03-1.18) for low. The same tendency was observed in K6 cases.

LIMITATION

Depressive state was identified by self-administered questionnaire.

CONCLUSIONS

Lower social support during pregnancy is associated with increased counterfactual risk of perinatal/postpartum depressive state and worsened counterfactual spontaneous recovery over time. These findings highlight the importance of sufficient social support for preventing perinatal/postpartum depression and promoting recovery.

TRIAL REGISTRATION

UMIN000030786.

Prospective association of air purifier use during pregnancy with the neurodevelopment of toddlers in the Japan Environment and Children's Study

We examined the association between maternal air purifier use during pregnancy and neurodevelopmental delay in toddlers by analysing data from 82,457 mother-toddler pairs. Air purifier use was measured using a simple yes/no question. Developmental delays at 1.5, 2.0, 2.5, and 3.0 years were assessed using the Ages and Stages Questionnaire, Third Edition. Generalized additive mixed model analysis with 21 covariates revealed that air purifier use was associated with lower prevalence of developmental delay in all five areas—communication, gross motor, fine motor, problem solving, and personal-social—at all four time points (adjusted risk ratios ranged from 0.827 to 0.927, and only one 95% confidence interval crossed the reference). These findings suggest a negative association between air purifier use during pregnancy and neurodevelopmental delay in toddlers.

Trial registration: UMIN000030786 (15/01/2018).

Association of cesarean birth with prevalence of functional constipation in toddlers at 3 years of age: results from the Japan Environment and Children's Study (JECS)

BACKGROUND

The association between delivery mode and subsequent development of diseases is a growing area of research. Cesarean delivery affects the diversity of the microbiota in the infant gut, which may be associated with gastrointestinal disorders, including functional constipation, in infants. In this study, we investigated the association between delivery mode and prevalence of functional constipation in 3-year-old Japanese toddlers.

METHODS

This study used data from the Japan Environment and Children's Study, an ongoing nationwide birth cohort study. We analyzed 71,878 toddler-mother pairs. The presence of functional constipation was determined according to the Rome III diagnostic criteria. Odds ratios and 95% confidence intervals were calculated using logistic regression analysis.

RESULTS

The prevalence of functional constipation in 3-year-old Japanese toddlers was estimated to be 12.3%. Logistic regression analysis revealed that the prevalence of functional constipation was higher in toddlers born by cesarean delivery (13.1%) compared with those born by vaginal delivery (12.1%), independent of 22 confounders (adjusted odds ratios = 1.064, 95% confidence interval = 1.004-1.128).

CONCLUSIONS

We determined the prevalence of functional constipation in 3-year-old Japanese toddlers and found that delivery mode was associated with the prevalence of functional constipation in Japanese toddlers.

Effect estimate of time-varying social support and trust on the physical and mental health of mothers at 2.5 years postpartum: The Japan Environment and Children's Study (JECS)

BACKGROUND

Many epidemiological studies have reported the association between various social factors and health status in mothers during and after pregnancy. However, little is known about their joint and longitudinal impact. We therefore examined the association of lack of social support and trust during pregnancy and at 2.5 years postpartum with health status in mothers.

METHODS

To adequately address time-varying exposure, marginal structural models were fitted to a pseudopopulation constructed by inverse probability weighting. The model included records of 90,071 mothers participating in the Japan Environment and Children's Study. Social support and trust were measured using a 9-item questionnaire (Q1-9). Mental and physical health were measured using Mental and Physical Component Summary scores from the 8-item Short-Form Health Survey.

RESULTS

For the Mental Component Summary, the magnitude of the effect estimate was largest when participants lacked close friends/neighbors (Q4) at only 2.5 years postpartum (= -6.23), followed by a lack in emotional support (Q2) at the same time point (= -4.94). For the Physical Component Summary, effect estimates were negligible. The magnitude of the effect estimates of lack of social support and trust tended to be larger when there was a lack at only 2.5 years postpartum than at both time points.

CONCLUSIONS

These findings suggest that, after childbirth, a loss in social support, particularly in a concrete or instrumental aspect, carries high risk, especially for mental health. Our results highlight the importance of supporting mothers for more than a few years after pregnancy.