The Risk of Gestational Diabetes Mellitus Following Bereavement: A Cohort Study from Denmark and Sweden

Parental history of psychiatric disorders and risk of type 1 diabetes in the offspring

OBJECTIVE

To examine risk of type 1 diabetes mellitus (T1DM) in the offspring of parents with a psychiatric history at the birth of the child, which would suggest potential shared familial or environmental risk factors between T1DM and psychiatric disorders.

METHODS

We established a cohort including all children born in Sweden in 1997-2016, and their parents. Children were followed up from birth until 31 Dec 2017, using national registers. Relative risk for T1DM was estimated by incidence rate ratios (RR) with 95% confidence intervals (CI), calculated from Poisson regression. We examined psychiatric subtypes, T1DM risk within subgroups and in relation to the timing of exposure.

RESULTS

The study cohort included 1,497,949 children. During follow-up, 7,794 cases of T1DM were identified. Children of mothers with psychiatric disorders at delivery had a higher risk of T1DM (RR 1.10 [95%CI 1.01-1.20]). Psychiatric diagnoses in fathers or assigned after delivery was not associated with increased T1DM risk. The observed association disappeared after adjusting for T1DM in parents; however, remained significant in female offspring. Maternal eating disorder (RR 1.53 [1.17-2.00]) and obsessive-compulsive disorder (RR 1.62 [1.02-2.58]) were associated with offspring T1DM, independent of parental T1DM.

CONCLUSION

Our results do not support a strong genetic link between psychiatric conditions and T1DM. However, the risks of offspring T1DM were increased in subgroups of female offspring and in offspring of mothers with a history of eating disorder or obsessive-compulsive disorder, independent of heredity for T1DM, which may warrant further investigation in future studies.

The Swedish medical birth register during five decades: documentation of the content and quality of the register

Pregnancy-related factors are important for short- and long-term health in mothers and offspring. The nationwide population-based Swedish Medical Birth Register (MBR) was established in 1973. The present study describes the content and quality of the MBR, using original MBR data, Swedish-language and international publications based on the MBR.The MBR includes around 98% of all births in Sweden. From 1982 onwards, the MBR is based on prospectively recorded information in standardized antenatal, obstetric, and neonatal records. When the mother and infant are discharged from hospital, this information is forwarded to the MBR, which is updated annually. Maternal data include information from first antenatal visit on self-reported obstetric history, infertility, diseases, medication use, cohabitation status, smoking and snuff use, self-reported height and measured weight, allowing calculation of body mass index. Birth and neonatal data include date and time of birth, mode of delivery, singleton or multiple birth, gestational age, stillbirth, birth weight, birth length, head circumference, infant sex, Apgar scores, and maternal and infant diagnoses/procedures, including neonatal care. The overall quality of the MBR is very high, owing to the semi-automated data extraction from the standardized regional electronic health records, Sweden's universal access to antenatal care, and the possibility to compare mothers and offspring to the Total Population Register in order to identify missing records. Through the unique personal identity numbers of mothers and live-born offspring, the MBR can be linked to other health registers. The Swedish MBR contains high-quality pregnancy-related information on more than 5 million births during five decades.

Bereavement Among Adult Siblings: An Examination of Health Services Utilization and Mental Health Outcomes

We aimed to examine the association of young and middle-aged sibling bereavement with use of health services and risk of developing mental health disorders over 24 months before and after sibling's death. All persons aged 18-56 years who died of illness/natural causes between 2009 and 2016 were identified in the Danish Register of Causes of Death. The study sample included 31,842 bereaved siblings and 31,842 age- and sex-matched controls. Overall, the largest effect was observed for increased use of psychological services: For women, the peak was observed 4-6 months after the death (odds ratio (OR) = 3.31, 95% confidence interval (CI): 2.85, 3.85) and for men in the first 3 months after the death (OR = 2.63, 95% CI: 2.06, 3.36). The peak of being diagnosed in a hospital setting with any mental disorder for women was observed in the period 13-15 months after sibling death (OR = 1.52, 95% CI: 1.11, 2.07) and for men in the first 3 months after the death (OR = 1.75, 95% CI: 1.32, 2.32). Young and middle-aged adults who experienced the death of a sibling are more likely to use health services and are at risk of poorer mental health outcomes. During the bereavement process, young and middle-aged siblings are especially in need of mental health support, such as professional psychological counseling.

Adrenal, metabolic and cardio-renal dysfunction develops after pregnancy in rats born small or stressed by physiological measurements during pregnancy

KEY POINTS

Women born small are at an increased risk of developing pregnancy complications. Stress may further increase a woman's likelihood for an adverse pregnancy. Adverse pregnancy adaptations can lead to long-term diseases even after her pregnancy. The current study investigated the effects of stress during pregnancy on the long-term adrenal, metabolic and cardio-renal health of female rats that were born small. Stress programmed increased adrenal Mc2r gene expression, a higher insulin secretory response to glucose during intraperitoneal glucose tolerance test (+36%) and elevated renal creatinine clearance after pregnancy. Females that were born small had increased homeostatic model assessment-insulin resistance and elevated systolic blood pressure after pregnancy, regardless of stress exposure. These findings suggest that being born small or being stressed during pregnancy programs long-term adverse health outcomes after pregnancy. However, stress in pregnancy does not exacerbate the long-term adverse health outcomes for females that were born small.

ABSTRACT

Females born small are more likely to experience complications during their pregnancy, including pregnancy-induced hypertension, pre-eclampsia and gestational diabetes. The risk of developing complications is increased by stress exposure during pregnancy. In addition, pregnancy complications may predispose the mother to diseases after pregnancy. We determined whether stress during pregnancy would exacerbate the adrenal, metabolic and cardio-renal dysfunction of growth-restricted females in later life. Late gestation bilateral uterine vessel ligation was performed in Wistar Kyoto rats to induce growth restriction. At 4 months, growth-restricted and control female offspring were mated with normal males. Those allocated to the stressed group had physiological measurements [metabolic cage, tail cuff blood pressure, intraperitoneal glucose tolerance test (IPGTT)] conducted during pregnancy whilst the unstressed groups were unhandled. After the completion of pregnancy, dams were aged to 12 months and blood pressure, and metabolic and renal function were assessed. At 13 months, adrenal glands, pancreases and plasma were collected at post-mortem. Females stressed during pregnancy had increased adrenal Mc2r gene expression (+22%), higher insulin secretory response to glucose during IPGTT (+36%) and higher creatinine clearance (+29%, indicating increased estimated glomerular filtration rate). In contrast, females that were born small had increased homeostatic model assessment-insulin resistance (+54%), increased water intake (+23%), urine output (+44%) and elevated systolic blood pressure (+7%) regardless of exposure to stress. Our findings suggest that low maternal birth weight and maternal stress exposure during pregnancy are both independently detrimental for long-term adrenal, metabolic and cardio-renal health of the mother, although their effects were not exacerbated.

Programming of maternal and offspring disease: impact of growth restriction, fetal sex and transmission across generations

Babies born small are at an increased risk of developing myriad adult diseases. While growth restriction increases disease risk in all individuals, often a second hit is required to unmask 'programmed' impairments in physiology. Programmed disease outcomes are demonstrated more commonly in male offspring compared with females, with these sex-specific outcomes partly attributed to different placenta-regulated growth strategies of the male and female fetus. Pregnancy is known to be a major risk factor for unmasking a number of conditions and can be considered a 'second hit' for women who were born small. As such, female offspring often develop impairments of physiology for the first time during pregnancy that present as pregnancy complications. Numerous maternal stressors can further increase the risk of developing a maternal complication during pregnancy. Importantly, these maternal complications can have long-term consequences for both the mother after pregnancy and the developing fetus. Conditions such as preeclampsia, gestational diabetes and hypertension as well as thyroid, liver and kidney diseases are all conditions that can complicate pregnancy and have long-term consequences for maternal and offspring health. Babies born to mothers who develop these conditions are often at a greater risk of developing disease in adulthood. This has implications as a mechanism for transmission of disease across generations. In this review, we discuss the evidence surrounding long-term intergenerational implications of being born small and/or experiencing stress during pregnancy on programming outcomes.

Maternal bereavement and the risk of preterm delivery: the importance of gestational age and of the precursor of preterm birth

BACKGROUND

Maternal stress during pregnancy may increase the risk of preterm delivery (PD), but the associations between stress and subtypes of PD are not clear. We investigated maternal loss of a close relative and risks of very and moderately PD (<32 and 32-36 weeks, respectively) and spontaneous and medically indicated PD.

METHOD

We studied 4 940 764 live singleton births in Denmark (1978-2008) and Sweden (1973-2006). We retrieved information on death of women's family members (children, partner, siblings, parents), birth outcomes and maternal characteristics from nationwide registries.

RESULTS

Overall, the death of a close family member the year before pregnancy or in the first 36 weeks of pregnancy was associated with a 7% increased risk of PD [95% confidence interval (CI) 1.04-1.10]. The highest hazard ratios (HR) for PD were found for death of an older child [HR (95% CI) 1.20 (1.10-1.31)] and for death of a partner [HR (95% CI) 1.31 (1.03-1.66)]. These losses were associated with higher risks of very preterm [HR (95% CI) 1.61 (1.29-2.01) and 2.07 (1.15-3.74), respectively] than of moderately preterm [HR (95% CI) 1.14 (1.03-1.26) and 1.22 (0.94-1.58), respectively] delivery. There were no substantial differences in the association between death of a child or partner and the risk of spontaneous v. medically indicated PD.

CONCLUSIONS

Death of a close family member the year before or during pregnancy was associated with an increased risk of PD, especially very PD. Possible mechanisms include both spontaneous and medically indicated preterm birth.