The relationship of nocturnal melatonin to estradiol and progesterone in depressed and healthy pregnant women

The pathophysiology of estrogen in perinatal depression: conceptual update

PURPOSE

Estrogen levels fall sharply after parturition and have long been considered an etiologic contributor to postpartum depression (PPD); however, no differences have been reported in plasma hormone concentrations in people who develop PPD. We examine the question: What is the current view of estrogen and the neurophysiologic processes it impacts in the development and treatment of PPD?

METHODS

A literature review of the role of estrogen on candidate hormonal and epigenetic systems in the peripartum period was performed, including landmark historical studies and recent publications on estrogen-related research. The authors reviewed these papers and participated in reaching consensus on a conceptual framework of estrogen activity within the complexity of pregnancy physiology to examine its potential role for driving novel interventions.

RESULTS

Estrogen fluctuations must be conceptualized in the context of multiple dramatic and interacting changes inherent in pregnancy and after birth, including progesterone, corticosteroids, inflammation, circadian biology and psychosocial challenges. Individuals who develop PPD have increased sensitivity to epigenetic alteration at estrogen-responsive genes, and these changes are highly predictive of PPD. An effective estrogen-based treatment for PPD has yet to be found, but interventions focused on associated inflammation and circadian rhythms are promising.

CONCLUSIONS

Our understanding of the biological basis of PPD, one of the most common morbidities of the perinatal period, is expanding beyond changes in gynecologic hormone concentrations to include their impact on other systems. This growing understanding of the many processes influencing PPD will allow for the development of novel prevention and treatment strategies.

Overlapping action of melatonin and female reproductive hormones-Understand the impact in pregnancy and menopause

Melatonin is an indolamine secreted to circulation by the pineal gland according to a circadian rhythm. Melatonin levels are higher during nighttime, and the principal function of this hormone is to organize the temporal night and day distribution of physiological adaptive processes. Besides hormonal pineal production, melatonin is synthesized in various organs and tissues like the ovaries or the placenta for local utilization. In addition to its function as a circadian messenger, melatonin is also associated with many physiological functions. For example, melatonin has antioxidant properties and is involved in the regulation of energy and bone metabolism, and reproduction. Melatonin impacts several stages of reproduction and the action across the hypothalamus-pituitary-gonadal axis is well described. However, it is not well understood how those actions impact the female reproductive hormones secretion nor the consequent physiological outcomes. Thus, the first part of this chapter describes the regulation of female reproductive hormone synthesis by melatonin. Moreover, melatonin and female reproductive hormones have coincident physiological functions. Life stages like pregnancy or menopause are characterized by alterations in the reproductive hormones secretion that may be associated with certain physiological stages. Therefore, the second part discusses whether melatonin fluctuations could have an overlapping role with reproductive hormones in contributing to clinical outcomes associated with pregnancy and menopause.

Critically-timed sleep+light interventions differentially improve mood in pregnancy vs. postpartum depression by shifting melatonin rhythms

BACKGROUND

Testing the hypothesis that combined wake + light therapy improves mood in pregnant vs. postpartum depressed participants (DP) by differentially altering melatonin and sleep timing.

METHODS

Initially 89 women, 37 pregnant (21 normal controls-NC; 16 DP) and 52 postpartum (27 NCs; 25 DP), were randomized to a parallel trial of a phase-delay intervention (PDI): 1-night of early-night wake therapy (sleep 3-7 am) + 6-weeks of evening bright white light (Litebook Advantage) for 60 min starting 90 min before bedtime, vs. a Phase-advance intervention (PAI): 1-night of late-night wake therapy (sleep 9 pm-1 am) + 6-weeks of morning bright white light for 60 min within 30 min of wake time. Blinded clinicians assessed mood weekly by structured interview, and participants completed subjective ratings, a Morningness-Eveningness questionnaire, actigraphy, and collected 2 overnight urine samples for 6-sulphatoxy melatonin (6-SMT).

RESULTS

In pregnant DP, mood improved more after the PDI vs. PAI (p = .016), whereas in postpartum DP, mood improved more after the PAI vs. PDI (p = .019). After wake therapy, 2 weeks of light treatment was as efficacious as 6 weeks (p > .05). In postpartum DP, PAI phase-advanced 6-SMT offset and acrophase (p < .05), which correlated positively with mood improvement magnitude (p = .003).

LIMITATIONS

Small N.

CONCLUSIONS

Mood improved more after 2 weeks of the PDI in pregnant DP, but more after 2 weeks of PAI in postpartum DP in which improvement magnitude correlated with 6-SMT phase-advance. Thus, critically-timed Sleep + Light Interventions provide safe, efficacious, rapid-acting, well-tolerated, at-home, non-pharmaceutical treatments for peripartum DP.

Variation in genes and hormones of the hypothalamic-pituitary-ovarian axis in female mood disorders - A systematic review and meta-analysis

Women's increased risk for depression during reproductive transitions suggests an involvement of the hypothalamic-pituitary-ovarian (HPO) axis. This is the first systematic review and meta-analysis of HPO functioning in female mood disorders. Inclusionary criteria were: i) women suffering from premenstrual dysphoric disorder (PMDD) or a depressive disorder, ii) assessment of HPO-axis related biomarkers, iii) a case-control design. Sixty-three studies (N = 5,129) were included. There was evidence for PMDD to be paralleled by lower luteal oestradiol levels. Women with depression unrelated to reproductive transition showed lower testosterone levels than healthy controls and there was some evidence for lower dehydroepiandrosterone sulfate levels. There were no differences in HPO-related parameters between women with pregnancy, postpartum, and perimenopausal depression and controls. Women with PMDD and depression unrelated to reproductive transitions exhibit specific changes in the HPO-axis, which potentially contribute to their symptoms. Further research into reproductive mood disorders characterised by extreme endocrine changes is warranted.

Neuroendocrine Effects of Lactation and Hormone-Gene-Environment Interactions

While correlational studies suggest that lactation may confer a certain level of protection from mental illness, this benefit is not uniformly expressed in all women who choose to breastfeed. We propose here that the neuroendocrine "resetting" induced by lactation may predispose toward positive affect states in a subset of hormone-sensitive mothers, with hormone-gene and hormone-environment interactions determining the ultimate psychological outcome. We find evidence to suggest that higher secretion of prolactin/oxytocin as well as lower secretion of vasopression/androgens in lactating mothers may protect against postpartum depression and anxiety, decrease levels of irritability, and optimize stress responses. On the other hand, while the abrupt withdrawal of estradiol/progesterone in the immediate postpartum period tends to be associated with adverse psychological outcomes, the chronic suppression of estrogens/progestogens induced by lactation may have antidepressant and anxiolytic effects over time. Finally, the hypo-cortisolemic state seen in lactating mothers appears to be associated with improved stress reactivity and circadian rhythms. We also discuss hormone-gene and hormone-environment interactions likely to modulate any potential psychological benefits related to lactation and focus on those factors that are either easy to screen for or known to be modifiable. In sum, neuroendocrine alterations induced by lactation may play a key role in determining reproductive psychiatric risk in a subset of hormone-sensitive women. Using these neuroendocrine factors as an individualized index of risk can help in devising targeted programs to support these women in pursuing lactation or, for those not able or willing, accessing psychological interventions in a timely manner.

Night work during pregnancy and preterm birth-A large register-based cohort study

BACKGROUND

Melatonin stimulates the production of progesterone, which is essential for the maintenance of pregnancy. Since melatonin in blood is reduced due to work under illuminated conditions during night work, it has been hypothesized that night work may increase the risk of preterm birth. Previous meta-analyses have not revealed increased risk of preterm birth in women working night shifts during pregnancy. Still, these studies might have been limited by inaccurate self-reports of timing, intensity and duration of night work most likely causing bias towards the null. The aim of this is study was to investigate if the frequency and duration of night work during the first (week 1-12) and second (week 13-22) trimester of pregnancy were associated with risk of preterm birth when objective and prospective data on night work are used.

METHOD

In a register-based prospective cohort study, we obtained individual day-to-day information on working hours from The Danish Working Hour Database (DWHD, a payroll database including all public service employees in administrative Danish Regions from 2007-2013) and information on preterm birth from the Danish Medical Birth Registry. Night-shift was defined as at least three working hours between 23:00 and 06:00. Preterm birth was defined as giving birth during gestational weeks 23-37. Odds of preterm birth according to working night shifts were analysed by logistic regression.

RESULTS

We identified 16,501 pregnant women eligible for the study, of which 10,202 women (61.8%) had at least one night-shift during the first 22 gestational weeks. The risk of preterm birth was not elevated among women working night shifts compared to women working only day shifts during either the first or second trimester. Within night-shift workers, the risk was not related to the number of night shifts, the duration of night shifts, consecutive night shifts or quick returns defined as short intervals between shifts. Odds of preterm birth was not related to change of working schedule from the first to second trimester, although women changing from night shifts in the first trimester to day work only in the second trimester displayed a weak increased odds of preterm birth (OR 1.21, 95%CI 0.98-1.49) compared to women working night shifts in both trimesters.

CONCLUSION

Our results, which are without bias from self-report of either exposure or outcome, are in line with the results of previous meta-analyses. Due to the detailed information on hours worked during pregnancy, we were able to investigate several dimensions of night work not previously investigated, of which none were associated with elevated risk of preterm birth.

Depression precedes, but does not follow, gestational diabetes

OBJECTIVES

To determine whether past history of depression is associated with increased rates of gestational diabetes, and whether history of gestational diabetes is associated with increased rates of postpartum depression.

RESEARCH DESIGN

Data for this case-control study consisted of de-identified chart records for 1439 women who received pregnancy care at a large university hospital between 1998 and 2017.

RESULTS

A history of depression prior to pregnancy was associated with gestational diabetes requiring insulin, although not with subtler degrees of gestational hyperglycemia. Diabetes in pregnancy was not associated with an increased risk of postpartum depression. Trauma history was associated with both impaired glucose tolerance in pregnancy and postpartum depression.

CONCLUSIONS

Past episodes of depression increase risk for the most severe form of gestational diabetes; however, gestational diabetes does not contribute significantly to risk for postpartum depression. This suggests a unidirectional association, unlike the bidirectional association of diabetes with depression among the general population. History of trauma increases risk for both gestational hyperglycemia and postpartum depression, suggesting important health effects of trauma that may differ measurably from those associated with depression.

Relationships of salivary cortisol and melatonin rhythms to sleep quality, emotion, and fatigue levels in patients with newly diagnosed lung cancer

PURPOSE

After being diagnosed with lung cancer, patients often experience sleep disturbance, anxiety, depression, and fatigue. These symptoms may occur because of changes in neurotransmitter secretion caused by tumors. This study investigated the correlation of cortisol and melatonin rhythms with sleep quality, anxiety, depression, and fatigue levels in patients with newly diagnosed lung cancer.

METHOD

We conducted a case-control study and recruited 40 patients with newly diagnosed lung cancer and 40 healthy adults.

RESULTS

The patient group had a lower salivary melatonin level and flatter slope (p < 0.001 and p < 0.001), higher salivary cortisol level and steeper slope (p < 0.001 and p < 0.001), higher sleep disturbance level (p = 0.004), and higher depression level (p < 0.001). The multivariate linear regression analysis indicated that the cortisol slope (p = 0.005) and fatigue score (p = 0.032) predicted the sleep quality score (p = 0.011).

CONCLUSION

Overall, the patients with newly diagnosed lung cancer had poorer sleep quality, higher depression levels, lower salivary melatonin levels, higher cortisol levels, and flatter melatonin and cortisol slopes than did the controls. The fatigue level and cortisol slope significantly predicted sleep quality. Therefore, the assessment of cortisol and melatonin rhythms and levels could provide crucial information that may be beneficial for managing symptoms in patients with newly diagnosed lung cancer.

Decreased concentration of serum melatonin in nighttime compared with daytime female medical technologists in South Korea

Working during the night can disrupt the normal circadian rhythm by altering the melatonin level. A low level of melatonin is associated with an increased risk of cancer, possibly by decreasing the expression of tumor-suppressor genes, such as p53. To determine whether nighttime work is associated with melatonin level in serum as well as the expression of related genetic markers, we enrolled 100 female nighttime medical technologists employed at a hospital in South Korea. Melatonin concentration and melatonin receptor 1 (MT1) expression were significantly lower in nighttime than in daytime workers (1.84 pg/mL versus 4.04 pg/mL; 1.16 versus 1.61, respectively). However, p53 expression showed no difference between the groups. In summary, nighttime work could be an important risk factor for circadian disruption, but not a direct risk factor for cancer in medical technologists in South Korea.

Mild Depressive Symptoms During the Third Trimester of Pregnancy Are Associated with Disruptions in Daily Rhythms but Not Subjective Sleep Quality

BACKGROUND

Recent research in major depressive disorder suggests that dysregulation of the circadian system may be a core pathophysiological component. In pregnancy, women often experience significant disruptions in their daily rhythms, including changes in day-to-day schedule and sleep habits. Current evidence suggests that these disruptions in daily rhythms may adversely affect underlying circadian rhythmicity. The purpose of our study was to examine whether subjectively rated daily rhythm disruptions were associated with a greater incidence of depressive symptoms during the third trimester.

METHOD

Our study was a cross-sectional design, assessing sleep quality, symptoms of depression, and daily rhythm disruptions in 51 pregnant women in their third trimester.

RESULTS

We observed a significant relationship between mild depressive symptoms and disruptions in daily rhythms. While we initially observed a strong correlation between subjective sleep quality and depressive symptoms, this was attenuated after accounting for daily rhythm disruptions. Disruptions in daily social rhythms, eating patterns, and general activity were all significantly associated with depressive symptomatology.

CONCLUSION

Our findings point to a strong correlation between daily rhythm disruptions and prenatal depressive symptoms. Given that these daily rhythms are known to act as zeitgebers, longitudinal studies examining the directionality of this relationship between circadian rhythms and depressive symptoms during pregnancy are warranted.

Seasonality of Admissions for Mania: Results From a General Hospital Psychiatric Unit in Pondicherry, India

INTRODUCTION

Bipolar disorder is affected by variables that modulate circadian rhythm, including seasonal variations. There is evidence of a seasonal pattern of admissions of mania in various geographical settings, though its timing varies by region and climate. Variables such as age and gender have been shown to affect seasonality in some studies.

METHODOLOGY

Data on monthly admission patterns for mania at a general hospital psychiatry unit in Pondicherry, India, were collected for 4 years (2010-2013) and analyzed for seasonality and seasonal peaks. The effects of age and gender were analyzed separately.

RESULTS

There was overall evidence of a seasonal pattern of admissions for mania (P < .01, Friedman test for seasonality), with a peak beginning during the rainy season and ending before summer (P < .0.1, Ratchet circular scan test). Male sex (P < .005, Ratchet circular scan test) and age > 25 years (P < .005, Ratchet circular scan test) were specifically associated with this seasonal peak.

DISCUSSION

The effect of seasons on mania is complex and is modulated by a variety of variables. Our study is consistent with earlier research findings: a greater degree of seasonality for mania in men. It is possible that climatic and individual variables interact to determine seasonal patterns in bipolar disorder in a given setting.

Does Circadian Disruption Play a Role in the Metabolic-Hormonal Link to Delayed Lactogenesis II?

Breastfeeding improves maternal and child health. The American Academy of Pediatrics recommends exclusive breastfeeding for 6 months, with continued breastfeeding for at least 1 year. However, in the US, only 18.8% of infants are exclusively breastfed until 6 months of age. For mothers who initiate breastfeeding, the early post-partum period sets the stage for sustained breastfeeding. Mothers who experience breastfeeding problems in the early post-partum period are more likely to discontinue breastfeeding within 2 weeks. A major risk factor for shorter breastfeeding duration is delayed lactogenesis II (DLII; i.e., onset of milk "coming in" more than 72 h post-partum). Recent studies report a metabolic-hormonal link to DLII. This is not surprising because around the time of birth the mother's entire metabolism changes to direct nutrients to mammary glands. Circadian and metabolic systems are closely linked, and our rodent studies suggest circadian clocks coordinate hormonal and metabolic changes to support lactation. Molecular and environmental disruption of the circadian system decreases a dam's ability to initiate lactation and negatively impacts milk production. Circadian and metabolic systems evolved to be functional and adaptive when lifestyles and environmental exposures were quite different from modern times. We now have artificial lights, longer work days, and increases in shift work. Disruption in the circadian system due to shift work, jet-lag, sleep disorders, and other modern life style choices are associated with metabolic disorders, obesity, and impaired reproduction. We hypothesize that DLII is related to disruption of the mother's circadian system. Here, we review literature that supports this hypothesis, and describe interventions that may help to increase breastfeeding success.

The effect of hormone therapy on serum melatonin concentrations in premenopausal and postmenopausal women: a randomized, double-blind, placebo-controlled study

OBJECTIVES

Melatonin levels decrease physiologically with age, and possibly with the transition to menopause. The plausible influence of hormone therapy (HT) on melatonin is poorly understood. The aim of this randomized, placebo-controlled, double-blind trial was to investigate the effect of HT administration on serum melatonin concentrations in late premenopausal and postmenopausal women.

STUDY DESIGN

Analyses were carried out among 17 late premenopausal and 18 postmenopausal healthy women who participated in a prospective HT study in Finland. Serum melatonin was sampled at 20-min (21:00-24:00 h; 06:00-09:00 h) and 1-h (24:00-06:00 h) intervals at baseline and after 6 months with HT or placebo.

MAIN OUTCOME MEASURES

Melatonin levels and secretion profile after 6 months of HT compared to placebo.

RESULTS

Mean melatonin levels, mean melatonin exposure level (area under curve, AUC) and mean duration of melatonin secretion did not differ after 6 months with HT vs. placebo, irrespectively of the reproductive state. However, in postmenopausal women the melatonin peak time (acrophase) was delayed by 2.4h (2 h 21 min) on average after 6 months with HT vs. placebo (p<0.05). No interaction between time and group was detected when melatonin level was modelled before or after treatment.

CONCLUSIONS

Administration of HT to postmenopausal women alters melatonin peak time, but not melatonin levels. Further research on larger clinical samples is needed to better understand the effects of HT on melatonin profile.