Thyroid peroxidase autoantibodies and perinatal depression risk: A systematic review

The causal relationship between major depression disorder and thyroid diseases: A Mendelian randomization study and mediation analysis

BACKGROUND

Studies have been conducted on the relationship between depression and thyroid diseases and function, its causal relationship remains unclear.

METHODS

Using summary statistics of genome-wide association studies of European and East Asian ancestry, we conducted 2-sample bidirectional Mendelian randomization to estimate the association between MDD and thyroid function (European: normal range TSH, T4, T3, fT4, TPOAb levels and TPOAb-positives; East Asian: T4) and thyroid diseases (hypothyroidism, hyperthyroidism, and Hashimoto's thyroiditis), and used Mediation analysis to evaluate potential mediators (alcohol intake, antidepressant) of the association and calculate the mediated proportions.

RESULTS

It was observed a significant causal association between MDD on hypothyroidism (P = 8.94 × 10-5), hyperthyroidism (P = 8.68 × 10-3), and hashimoto's thyroiditis (P = 3.97 × 10-5) among European ancestry, which was mediated by Alcohol intake (alcohol intake versus 10 years previously for hypothyroidism (P = 0.026), hashimoto's thyroiditis (P = 0.042), and alcohol intake frequency for hypothyroidism (P = 0.015)) and antidepressant (for hypothyroidism (P = 0.008), hashimoto's thyroiditis (P = 0.010)), but not among East Asian ancestry (PMDD-hypothyroidism = 0.016, but β direction was different; PMDD-hyperthyroidism = 0.438; PMDD-hashimoto's thyroiditis = 0.496). There was no evidence for bidirectional causal association between thyroid function mentioned above and MDD among both ancestry (all P > 0.05).

CONCLUSION

We importantly observed a significant causal association between MDD on risk of hypothyroidism, hyperthyroidism, and hashimoto's thyroiditis among European ancestry, and Alcohol intake and antidepressant as mediators for prevention of hypothyroidism, hashimoto's thyroiditis attributable to MDD.

Selenium Intake and Postnatal Depression-A Short Review

Postnatal depression is a common and severe complication of childbirth. It is an important public health problem with significant implications for both mothers and children. The exact mechanisms underlying and the factors influencing the occurrence of postnatal depression remain unclear. The literature suggests that certain dietary deficiencies during pregnancy and the postnatal period may contribute to a greater risk of maternal depression. This review focuses on the role of selenium in postnatal depression. It collects evidence from published interventional and observational studies investigating the relationship between selenium intake during the antenatal and postnatal periods and the mental status of postpartum women and summarises information about biological mechanisms that may underlie the association between selenium status and postnatal depression. The review includes studies identified through electronic searches of Medline (via PubMed) and Google Scholar databases until December 2023. Despite the small number of relevant studies and their potential methodological limitations, the findings suggest that optimizing selenium status may support the prevention and treatment of postnatal depression. Further longitudinal and interventional studies are necessary to confirm the clinical significance of these effects.

Prenatal Iodine Intake and Maternal Pregnancy and Postpartum Depressive and Anhedonia Symptoms: Findings from a Multiethnic US Cohort

Objective: Emerging evidence suggests that essential trace elements, including iodine, play a vital role in depressive disorders. This study investigated whether prenatal dietary iodine intake alone and in combination with supplemental iodine intake during pregnancy were associated with antepartum and postpartum depressive and anhedonia symptoms. Methods: The study population included 837 mothers in the PRogramming of Intergenerational Stress Mechanisms (PRISM) study. The modified BLOCK food frequency questionnaire was used to estimate prenatal dietary and supplemental iodine intake, while the 10-item Edinburg Postpartum Depression Scale (EPDS) ascertained depressive symptoms. Analyses considered the global EPDS score and the anhedonia and depressive symptom subscale scores using dichotomized cutoffs. Logistic regression estimating odds ratios and 95% confidence intervals (CIs) assessed associations of iodine intake in the second trimester of pregnancy and 6-month postpartum depressive and anhedonia symptoms considering dietary intake alone and combined dietary and supplementary intake in separate models. Results: Most women were Black/Hispanic Black (43%) and non-Black Hispanics (35%), with 39% reporting a high school education or less. The median (interquartile range, IQR) dietary and supplemental iodine intake among Black/Hispanic Black (198 (115, 337) µg/day) and non-Black Hispanic women (195 (126, 323) µg/day) was higher than the overall median intake level of 187 (116, 315) µg/day. Relative to the Institute of Medicine recommended iodine intake level of 160-220 µg/day, women with intake levels < 100 µg/day, 100-<160 µg/day, >220-<400 µg/day and ≥400 µg/day had increased adjusted odds of 6-month postpartum anhedonia symptoms (aOR = 1.74 (95% CI: 1.08, 2.79), 1.25 (95% CI: 0.80, 1.99), 1.31 (95% CI: 0.82, 2.10), and 1.47 (95% CI: 0.86, 2.51), respectively). The corresponding estimates for postpartum global depressive symptoms were similar but of smaller magnitude. Conclusions: Prenatal iodine intake, whether below or above the recommended levels for pregnant women, was most strongly associated with greater anhedonia symptoms, particularly in the 6-month postpartum period. Further studies are warranted to corroborate these findings, as dietary and supplemental iodine intake are amenable to intervention.

Autoimmune diseases and adverse pregnancy outcomes: an umbrella review

BACKGROUND

There is a high prevalence of autoimmune conditions in women specially in the reproductive years; thus, the association with adverse pregnancy outcomes has been widely studied. However, few autoimmune conditions/adverse outcomes have been studied more than others, and this umbrella review aims to consolidate existing knowledge in this area with the aim to provide new knowledge and also identify gaps in this research area.

METHODS

Medline, Embase, and Cochrane databases were searched from inception to December 2023. Screening, data extraction, and quality appraisal (AMSTAR 2) were done by two independent reviewers. Data were synthesised narratively and quantitatively. Relative risks (RR)/odds ratio (OR) with 95% confidence intervals were reported.

RESULTS

Thirty-two reviews were included consisting of 709 primary studies. The review reported the association between 12 autoimmune conditions and 16 adverse pregnancy outcomes. Higher risk of miscarriage is reported in women with Sjögren's syndrome RR 8.85 (95% CI 3.10-25.26) and systemic lupus erythematosus (SLE) OR 4.90 (3.10-7.69). Pre-eclampsia was reported higher in women with type 1 diabetes mellitus (T1DM) OR 4.19 (3.08-5.71) and SLE OR 3.20 (2.54-4.20). Women reported higher risk of diabetes during pregnancy with inflammatory bowel disease (IBD) OR 2.96 (1.47-5.98). There was an increased risk of intrauterine growth restriction in women with systemic sclerosis OR 3.20 (2.21-4.53) and coeliac disease OR 1.71 (1.36-2.14). Preterm birth was associated with T1DM OR 4.36 (3.72-5.12) and SLE OR 2.79 (2.07-3.77). Low birth weight babies were reported in women with women with SLE or systemic sclerosis OR 5.95 (4.54-7.80) and OR 3.80 (2.16-6.56), respectively. There was a higher risk of stillbirth in women with T1DM OR 3.97 (3.44-4.58), IBD OR 1.57 (1.03-2.38), and coeliac disease OR 1.57 (1.17-2.10). T1DM in women was associated with 32% lower odds of small for gestational age baby OR 0.68 (0.56-0.83).

CONCLUSIONS

Pregnant women with autoimmune conditions are at a greater risk of developing adverse pregnancy outcomes. Further research is required to develop better preconception to postnatal care for women with autoimmune conditions.

Thyroid Predictors of Postpartum Mood Disorders

Postpartum mood disorders (PMD) are currently among the leading causes of maternal postpartum morbidity and mortality. PMD include the conditions of postpartum blues (PB), postpartum depression (PPD), and postpartum psychosis. The pathogenesis of PMDs are ambiguous, and there are no reliable prenatal predictive markers despite current research efforts. Even though reliable indicators have not been found, leading ideas suggest an etiology of hormonal fluctuations. Although thyroid markers have long been linked to psychiatric disorders such as major depressive disorder (MDD), how they correlate with PMDs is still unclear. This study aimed to evaluate the pathophysiological link between thyroid function, PMDs, and the usefulness of thyroid markers as indicators of their occurrence and severity. The methodology consisted of a narrative literature review. Several inclusion and exclusion criteria were used to filter the results of literature searches in PubMed. Studies were included if they discussed any marker related to thyroid endocrinology in relation to the incidence or pathophysiology of any PMD. Both primary and secondary analyses were included. The permissive inclusion criteria were used due to the relative scarcity of research on the topic and the ambiguous pathophysiology of PMD. The results demonstrated the potential utility of thyroid autoimmunity as a predictor of late-onset PPD. Hypothyroidism, low euthyroid hormone levels, and the presence of thyroid autoantibodies were correlated with increased incidence of PPD and late postpartum depressive symptoms, past the timeline of PB. Most notably a rapid postpartum drop in cortisol level may precipitate thyroid autoimmunity in anti-thyroid peroxidase (TPO) antibody positive women, which could eventually produce a hypothyroid phase associated with depressive symptoms. There was insufficient evidence to suggest a relationship with postpartum psychosis. In conclusion, the exact pathophysiological mechanisms of PMDs remain ambiguous, but TPO-antibodies in the third trimester may be a predictor of late PPD.

Association of gestational thyroid function and thyroid peroxidase antibody positivity with postpartum depression: a prospective cohort study and systematic literature review with meta-analysis

IMPORTANCE

Postpartum depression (PPD) has a major impact on maternal and offspring well-being, with multiple possible risk factors: Studies on the association of thyroid peroxidase antibody (TPOAb) positivity and thyroid function with PPD provide heterogeneous results.

OBJECTIVE

To study the association of thyroid function and TPOAb positivity with PPD.

DESIGN

We assessed the association of TPOAb and thyroid function with PPD in a population-based prospective cohort study and performed a systematic literature review and meta-analysis.

METHODS

We measured thyroid stimulating hormone (TSH), free thyroxine (FT4), and TPOAb between 9- and 17-week gestation. Postpartum depression was assessed with Edinburgh Postpartum Depression Scale at 2-month postpartum and Brief Symptom Inventory at 2-, 6-, and 36-month postpartum. Additionally, we performed a systematic literature review and meta-analysis assessing this association.

RESULTS

In the present study, there was no association of thyroid function with PPD (TSH: odds ratio [OR] 0.83, 95% CI 0.58-1.19, P = .32; FT4: OR 0.99, 95% CI 0.95-1.05, P = .86) or TPOAb positivity with PPD (OR 0.79, 95% CI 0.47-1.33, P = .37). An impaired thyroidal response to human chorionic gonadotropin (hCG), a surrogate marker for TPOAb positivity, was associated with a lower risk of PPD (P for interaction TSH = 0.04; FT4 = 0.06). Our systematic review and meta-analysis included 3 articles that were combined with the present study. There was no statistically significant association of TPOAb positivity with PPD (OR 1.93, 95% CI 0.91-4.10, P = .08), but the results were heterogeneous (I2 = 79%).

CONCLUSIONS AND RELEVANCE

There was no significant association of TPOAb positivity, TSH, or FT4 with PPD. Our systematic review and meta-analysis revealed high heterogeneity of the current literature. Although TPOAb-positive women should be monitored for postpartum thyroiditis, our findings do not support routinely screening for PPD.

Mild-to-moderate iodine deficiency and symptoms of emotional distress and depression in pregnancy and six months postpartum - Results from a large pregnancy cohort

BACKGROUND

The relationship between iodine intake and depression is unknown. The aim of the present study was to investigate whether iodine intake was associated with symptoms of perinatal emotional distress and depression in a mild- to moderately iodine deficient population.

METHODS

The study population comprised 67,812 women with 77,927 pregnancies participating in the Norwegian Mother, Father and Child Cohort Study. Self-reported emotional distress and depressive symptoms were reported in pregnancy and at six months postpartum. Iodine intake was assessed by a food frequency questionnaire in mid-pregnancy. Urinary iodine concentration (UIC) was available for 2792 pregnancies.

RESULTS

The median iodine intake from food was 121 μg/day and the median UIC was 68 μg/L. The prevalence of high scores for emotional distress was 6.6 % in pregnancy and 5.8 % six months postpartum, and for high scores on postpartum depression it was 10.3 %. In non-users of iodine supplements (63 %), a low maternal iodine intake from food (lower than ~100-150 μg/day) was associated with increased risk of high scores of emotional distress and depression both in pregnancy and six months postpartum (p < 0.001). Iodine supplement use was associated with increased risk of high scores of emotional distress in pregnancy compared to no supplement use or use of supplements without iodine.

LIMITATIONS

Observational design, self-report information, and short scales to assess symptoms of emotional distress and depression.

CONCLUSION

A low habitual iodine intake was associated with increased prevalence of perinatal emotional distress and depression. The potential non-beneficial effect of iodine supplements may have biological explanations. More studies are needed.

Discrimination and structural validity evaluation of Zung self-rating depression scale for pregnant women in China

PURPOSE

The applicability of the Zung self-rating depression scale (SDS) in pregnancy is unknown. We aimed to identify redundant items and evaluate the Zung SDS's structural validity.

METHOD

Two samples of pregnant women were invited from two districts in Shanghai (Yangpu sample, n = 6468 and Huangpu sample, n = 402). The Yangpu sample was randomly split into YGroup1/2/3. Item's properties were evaluated via the item response theory in YGroup1. Exploratory and confirmatory factor analyses were correspondingly executed in YGroup2 and YGroup3. Those items with discrimination parameter (α) lower than 0.65 or factor loading smaller than 0.4 were deleted from the scale. The final structure was validated in the Huangpu sample.

RESULTS

Items 4 (sleep), 7 (weight loss), 8 (constipation) and 9 (tachyarrhythmia) exhibited low discrimination power. Items 2 (diurnal variation), 5 (appetite), 10 (fatigue) and 19 (suicide idea) made a low contribution to all factors. A three-factor model was eventually constructed as cognitive (Items 14, 16, 17, 18 and 20), psychomotor (Items 6, 11 and 12) and affective (Items 1, 3, 13 and 15).

CONCLUSION

The Zung SDS needs modification before applied to pregnant women in China. The items describing the overlap symptoms of the physical change in pregnancy and mood disorder should be deleted.

Thyroid Autoimmunity in Adverse Fertility and Pregnancy Outcomes: Timing of Assisted Reproductive Technology in AITD Women

Thyroid autoimmunity (TAI) is prevalent in women of live-birthing age and has independently been associated with complications of fertility and pregnancy, in the case of spontaneous conception or after assisted reproductive technology (ART) treatment. However, it remains challenging to identify causation between infertility and TAI, even interventional trials looking at the impact of levothyroxine (LT4) treatment on fertility and pregnancy outcomes due to differences among study results which related to small scales, impropriate study designs, enrollment criteria of infertility cause and titer/hormone concentration measurements. Furthermore, many questions remain unsettled in ART management in AITD infertile women attempt pregnancy. Therefore, further observational and interventional trials are needed more comprehensive multiple-center, double blinded, and randomized.

Contemporary management of unipolar depression in the perinatal period

Introduction: There is increasing recognition that antenatal depression and postpartum depression are highly prevalent and have significant impact on maternal and child health.Areas Covered: In the initial part of the manuscript, the authors review the epidemiology of antenatal and postpartum depression and its impact on maternal and child health. The later part of the manuscript reviews the current status of the medical management and psychosocial interventions targeting perinatal depression.Expert Opinion: Perinatal depression is the focus of several studies with increasing interest in developing effective interventions. While several psychosocial interventions targeting maternal depressive symptoms during pregnancy and postpartum are available, more studies are needed to address the need for safe and efficacious strategies for the use of antidepressant medication during pregnancy and in the postpartum period.

Postpartum Depression: Current Status and Possible Identification Using Biomarkers

Postpartum depression (PPD) is a serious health issue that can affect about 15% of the female population within after giving birth. It often conveys significant negative consequences to the offsprings. The symptoms and risk factors are somewhat similar to those found in non-postpartum depression. The main difference resides in the fact that PPD is triggered by postpartum specific factors, including especially biological changes in the hormone levels. Patients are usually diagnosed using a questionnaire onsite or in a clinic. Treatment of PPD often involves psychotherapy and antidepressant medications. In recent years, there have been more researches on the identification of biological markers for PPD. In this review, we will focus on the current research status of PPD, with an emphasis on the recent progress made on the identification of PPD biomarkers.

The Clinical Value and Variation of Antithyroid Antibodies during Pregnancy

Antithyroid antibodies, which include thyroid-stimulating hormone receptor antibodies (TRAbs), thyroid peroxidase antibodies (TPOAbs), and thyroid globulin antibodies (TgAbs), are widely known for their tight association with thyroid autoimmune diseases. The variation in all three kinds of antibodies also showed different trends during and after pregnancy (Weetman, 2010). This article reviewed the the physiological changes, while focusing on the variation of thyroid antibodies concentration in women during and after pregnancy, and adverse consequences related to their elevation. Since abnormal elevations of these antithyroid antibodies may lead to adverse outcomes in both mothers and fetuses, special attention must be paid to the titer of the antibodies during pregnancy. The molecular mechanisms of the variations in those antibodies have yet to be explained. The frequency and timing of thyroid antibody measurement, as well as different reference levels, also remain to be elucidated.

Risk factors for postpartum depression: An evidence-based systematic review of systematic reviews and meta-analyses

PURPOSE

Postpartum depression (PPD) is the most common psychiatric condition after childbirth which not only effects the mother's health, but also might have impact on child's development and parenting behaviors. Because the etiology of PPD has not been fully cleared, the efforts towards identification of risk factors are crucial for both the children and mother's health.

METHOD

PubMed, EMBASE and PsycINFO databases were searched since inception until July 2019 to collect data about the risk factors of PPD and only systematic review and meta-analysis can be included.

RESULT

To identify the real risk factors, protective factors and controversial factors, nineteen parts of the interpretation were adopted. The risk factors are mainly concentrated in the following aspects: violence and abuse, immigration status, gestational diabetes, cesarean section, depressive history, vitamin D deficiency, obese and overweight, postpartum sleep disruption and poor postpartum sleep, lack of social support, traditional dietary pattern (Japanese, Indian, United Kingdom, and Brazilian dietary pattern), multiple births, preterm and low-birth-weight infants, postpartum anemia, negative birth experience. The controversial factors are serum level of cortisol, thyroid peroxidase autoantibodies status, acculturation, traditional confinement practices. Skin-to-skin care, higher concentrations of DHA in mothers' milk, greater seafood consumption, healthy dietary patterns, multivitamin supplementation, fish and PUFA intake, calcium, Vitamin D, zinc and possibly selenium are protective factors.

CONCLUSION

Thirteen risk factors were identified, but five factors still controversial due to the insufficient of the evidence. What's more, skin-to-skin care and some nutrition related factors are protective factors against PPD.

Psychiatric Disorders in the Adolescent Offspring of Mothers with Thyroid Problems During Pregnancy

Maternal thyroid problems during pregnancy have been linked to neurocognitive impairments in children. While studies suggest that disorders of maternal thyroid function during pregnancy are associated with symptoms of mental health problems in children, little is known about the risk of clinically significant psychiatric disorders in adolescence. A sample of 2451 Canadian adolescents enrolled in the Ontario Child Health Study completed the Mini International Neuropsychiatric Interview for Children and Adolescents at 12-17 years of age. Their mothers self-reported thyroid problems during pregnancy. Gestational thyroid problems were associated with offspring oppositional defiant disorder (ODD; OR 3.73; 95% CI 1.69-8.24), conduct disorder (CD; OR 12.95; 95% CI 5.12-32.75), and social anxiety disorder (SAD; OR 6.25; 95% CI 2.53-15.47). Neither sex nor gestational age moderated associations between prenatal thyroid dysfunction and the majority of outcomes. School performance mediated 8% of the association between thyroid problems and SAD, 21% for CD and 53% for ODD.

Serum Metabolic Profiling Reveals the Antidepressive Effects of the Total Iridoids of Valeriana jatamansi Jones on Chronic Unpredictable Mild Stress Mice

Background

Depression is a long-term complex psychiatric disorder, and its etiology remains largely unknown. Valeriana jatamansi Jones ex Roxb (V. jatamansi) is used in the clinic for the treatment of depression, but there are insufficient reports of its antidepressive mechanisms and a poor understanding of its endogenous substance-related metabolism. The objective of this study was to identify biomarkers related to depression in serum samples and evaluate the antidepressive effects of the iridoid-rich fraction of V. jatamansi (IRFV) in a chronic unpredictable mild stress (CUMS) mouse model.

Methods

Here, CUMS was used to establish a mouse model of depression. Behavioral and biochemical indicators were investigated to evaluate the pharmacodynamic effects. A comprehensive serum metabolomics study by nuclear magnetic resonance (NMR) approach was applied to investigate the pharmacological mechanism of IRFV in CUMS mouse. Subsequently, we used multivariate statistical analysis to identify metabolic markers, such as principal component analysis (PCA) and orthogonal projection to latent structure with discriminant analysis (OPLS-DA), to distinguish between the CUMS mouse and the control group.

Results

After IRFV treatment, the immobility time, sucrose preference, and monoamine neurotransmitter were improved. PCA scores showed clear differences in metabolism between the CUMS group and control group. The PLS-DA or OPLS-DA model exhibited 26 metabolites as biomarkers to distinguish between the CUMS mice and the control mouse. Moreover, IRFV could significantly return 21 metabolites to normal levels.

Conclusion

The results confirmed that IRFV exerted an antidepressive effect by regulating multiple metabolic pathways, including the tricarboxylic acid cycle, the synthesis of neurotransmitters, and amino acid metabolism. These findings provide insights into the antidepressive mechanisms of IRFV.

Thyroid autoimmunity and risk of post-partum depression: a systematic review and meta-analysis of longitudinal studies

PURPOSE

The aim of this study was to systematically investigate whether, and to what extent, the detection of thyroid autoimmunity during pregnancy and in the weeks after childbirth is associated with an increased risk of developing post-partum depression (PPD), a condition associated with possible adverse outcomes for both mother and offspring. We performed a systematic review and meta-analysis of longitudinal studies, assessing the incidence of PPD in women with and without anti-thyroperoxidase antibody (TPOAb) positivity.

METHODS

We searched MEDLINE, EMBASE, Web of Science, Cochrane Library, and CINAHL. Methodological quality of the studies was assessed by the Newcastle-Ottawa Scale. In the presence of even modest between-studies heterogeneity, assessed by Cochrane Q and I² tests, risk ratios (RRs) for PPD were combined using a random effects model. Funnel plot and trim-and-fill analysis were used to assess publication bias.

RESULTS

Five included studies provided information on 449 women with TPOAb-positive and 2483 TPOAb-negative women. Pooled RR indicated a significantly increased risk to develop PPD in TPOAb-positive group (RR 1.49, 95% CI 1.11-2.00; P = 0.008; I² = 47%, P_{for heterogeneity} = 0.11). Consistent with a possible publication bias, the trim-and-fill test detected two putative missing studies in the funnel plot. Nevertheless, the adjustment for publication bias produced a negligible effect on the pooled estimate (adjusted RR 1.41, 95% CI 1.18-1.68, P = 0.0002).

CONCLUSIONS

Thyroid autoimmunity during pregnancy and in the weeks after childbirth is associated with an increased risk of developing PPD. Further well-designed studies are warranted to confirm this association and elucidate underlying pathophysiological mechanisms.

PROSPERO REGISTRATION

CRD42019129643.

Evaluation of the relationship between serum anti TPO antibody levels and mood disorders in euthyroid pregnant women

Introduction: Depression and anxiety during pregnancy have a negative impact on prenatal health and reduces mother's child care capability. Up to 20% of the pregnant women experience mood disorders.Objective: The aim of this study was evaluating the relationship between serum anti-TPO antibody levels and mood disorders in pregnant euthyroid women.Materials and methods: Serum anti-TPO antibody levels were measured in the first trimester of gestation in euthyroid pregnant women. Then, the women were divided into two groups of positive and negative anti-TPO antibody. Depression and anxiety were evaluated by Hamilton depression rating scale (HAM-D) and Hamilton anxiety rating scale (HAM-A) during the first, second, and third trimester of pregnancy (all women had three assessments during pregnancy).Results: Thirty women with high serum anti-TPO antibody levels (case group) and 32 women with normal serum anti-TPO antibody levels (control group) were compared. Mean anti-TPO levels were 105.63 ± 54.17 and 5.57 ± 1.80 IU/mL in case and control groups, respectively (p = .000). The baseline characteristics and initial HAM-A and HAM-D scores were not significantly different in the two groups except for anti-TPO. Pair t-test showed that the level of anxiety and depression has increased significantly during pregnancy in both groups. Comparison of anxiety and depression level in both groups showed that in anti-TPO antibody positive group, anxiety, and depression levels were significantly higher than the anti-TPO antibody negative group.Conclusion: Depression and anxiety of euthyroid pregnant women in the second and third trimester of pregnancy have a significant correlation with serum anti-TPO antibody levels of the first trimester of pregnancy.

Autoimmune thyroid disease during pregnancy

Understanding of changes in thyroid function and the consequences of thyroid disease during pregnancy has rapidly grown in the past two decades, and revised American Thyroid Association guidelines on this topic were published in 2017. This Review explores the association between thyroid autoimmunity and complications during and after pregnancy. Thyroid autoimmunity refers to the presence of antibodies to thyroperoxidase or thyroglobulin, or thyroid-stimulating hormone receptor antibodies (TRAbs), or a combination of these, and is present in up to 18% of pregnant women. Thyroid antibodies in pregnant women with normal functioning thyroids (ie, euthyroid) have been associated with several complications, including miscarriage and premature delivery. Treatments to improve pregnancy outcomes are being studied. Whether thyroid antibodies are associated with infertility and assisted reproductive technology outcomes is unclear; although, treatment with low doses of levothyroxine, which is usually used to treat hypothyroidism, can be considered in such situations. Additionally, thyroid antibodies have been associated with other neonatal and maternal complications. All these associations require confirmation in larger prospective studies, and their pathogenic mechanisms need to be better understood. Post-partum thyroiditis is substantially more frequent in women who have thyroid antibodies during pregnancy than in those who do not have thyroid antibodies; however, whether treatment can prevent post-partum thyroiditis in women who are or have been antibody positive is unknown. Finally, TRAbs cross the placenta from the mother to the fetus and can cause fetal or neonatal hyperthyroidism. Therefore, women who are positive for TRAbs during pregnancy should be monitored.

Thyroid peroxidase antibodies during early gestation and the subsequent risk of first-onset postpartum depression: A prospective cohort study

BACKGROUND

During the postpartum period, women are at risk for the new onset of both auto-immune thyroid disorders and depression. The presence of thyroid peroxidase antibodies (TPO-ab) during early gestation is predictive for postpartum auto-immune thyroid dysfunction. The aim of this study was to investigate the association between TPO-ab status during early gestation and first-onset postpartum depression.

METHODS

Prospective cohort study (n = 1075) with follow-up during pregnancy up to one year postpartum. Thyroid function and TPO-ab status were measured during early gestation. Depressive symptomatology was assessed during each trimester and at four time points postpartum with the Edinburgh Depression Scale (EDS). Women with antenatal depression were not eligible for inclusion. Self-reported postpartum depression was defined with an EDS cut-off of ≥ 13.

RESULTS

The cumulative incidence of self-reported first-onset depression in the first postpartum year was 6.3%. A positive TPO-ab status was associated with an increased risk for self-reported first-onset depression at four months postpartum (adjusted OR 3.8; 95% CI 1.3-11.6), but not at other postpartum time points. Prevalence rates of self-reported postpartum depression declined after four months postpartum in the TPO-ab positive group, but remained constant in the TPO-ab negative group.

LIMITATIONS

Depression was defined with a self-rating questionnaire (EDS).

CONCLUSIONS

Women with an increased TPO-ab titer during early gestation are at increased risk for self-reported first-onset depression. The longitudinal pattern of self-reported postpartum depression in the TPO-ab positive group was similar to the typical course of postpartum TPO-ab titers changes. This suggests overlap in the etiology of first-onset postpartum depression and auto-immune thyroid dysfunction. Thyroid function should be evaluated in women with first-onset postpartum depression.

Neuronal Surface Autoantibodies in Neuropsychiatric Disorders: Are There Implications for Depression?

Autoimmune diseases are affecting around 7.6-9.4% of the general population. A number of central nervous system disorders, including encephalitis and severe psychiatric disorders, have been demonstrated to associate with specific neuronal surface autoantibodies (NSAbs). It has become clear that specific autoantibodies targeting neuronal surface antigens and ion channels could cause severe mental disturbances. A number of studies have focused or are currently investigating the presence of autoantibodies in specific mental conditions such as schizophrenia and bipolar disorders. However, less is known about other conditions such as depression. Depression is a psychiatric disorder with complex etiology and pathogenesis. The diagnosis criteria of depression are largely based on symptoms but not on the origin of the disease. The question which arises is whether in a subgroup of patients with depression, the symptoms might be caused by autoantibodies targeting membrane-associated antigens. Here, we describe how autoantibodies targeting membrane proteins and ion channels cause pathological effects. We discuss the physiology of these antigens and their role in relation to depression. Finally, we summarize a number of studies detecting NSAbs with a special focus on cohorts that include depression diagnosis and/or show depressive symptoms.