From Prevention to Treatment: How Biological Rhythms Can Maintain Perinatal Mental Health

Depression and anxiety are significant public health issues during pregnancy and the postnatal period, particularly affecting those in developing countries. Disruptions in biological rhythms, sleep problems, and low exposure to daylight are associated with a higher risk of these mental health issues. The perinatal period poses unique challenges to the temporal program, with evidence indicating that sleep disturbances significantly increase the risk of postnatal depression. A Randomised Clinical Trial (RCT) is being conducted to assess the effectiveness of Blue Light Therapy (BlueLT) in treating depressive and anxiety symptoms during the postpartum. The RCT will also investigate the alignment of rest-activity and internal body time as mediating factors. This study will focus on various chronobiological factors, including rest-activity rhythms, light exposure levels, temperature rhythms, sleep duration and phase, social jetlag, and BodyTime (assessed through a single blood sample). The goal is to recruit 50 women with postpartum depression, with 25 in the BlueLT intervention group and 25 in the ControlLT placebo group, alongside 100 healthy controls. The BlueLT device uses a short-wavelength LED lamp mainly composed by a wavelength peak on blue spectrum, while the ControlLT device has a dim long-wavelength LED. A Healthy Control group will also be included to account for changes unrelated to depression diagnosis or placebo/treatment effects. Exclusion criteria involve a history of major depressive or anxiety disorder, current psychotic disorder, night shift work, active suicidal thoughts, unstable medical conditions interfering with data collection, and newborns with severe health conditions. The study aims to evaluate the impact of BlueLT on postpartum depression and understand the role of chronobiological factors in the health/disease process.

Depression and anxiety during both pregnancy and postnatal periods are major public health problems, with those living in developing countries being most vulnerable. Alterations in biological rhythms, sleep disturbances, and low daylight exposure have been linked with higher risk for these problems. When considering conditions that are known to produce misalignment, the perinatal period could be seen as a standalone model in which there are distinct challenges to the temporal program. Prior evidence suggests that both sleep onset latency and sleep deficits increases risk for symptoms of postnatal depression. In fact, sleep disturbances appear among the most common risk factors for postnatal depression and are linked to a four-fold increased risk for depression. Emerging evidence indicates that changes in factors related to circadian health, such as patterns of sleep, activity, and light exposure, affect mood during the peripartum period. Thus, chronobiological interventions may be promising strategies, from prevention to treatment. Thus, the Randomised Clinical Trial (RCT) aims to evaluate the effectiveness of Blue Light Therapy (BlueLT) in women with postpartum depression, and examine the alignment of rest-activity and internal body time as mediating variables. During the RCT, we will assess chronobiological factors and their implications on the health/disease process. The chronobiological factors that will be studied are rest-activity rhythms, levels of light exposure, temperature rhythms, sleep duration and phase, social jetlag, and BodyTime (a simple assay from a single blood sample taken at any time of the day). We will recruit women until we ensure the sample size for our nested BlueLT RCT: 50 women with postpartum depression, with 25 in the intervention group (BlueLT) and 25 in the placebo group (ControlLT), along with 100 healthy controls. The BlueLT device is equipped with a narrow band short wavelength Light Emitting Diode (LED) - wavelength peak(λp) of \~470 nm (blue). The ControlLT (placebo) device is equipped with a dim long-wavelength enriched LED. Because pregnancy and postpartum are periods at which changes in phase relationships may happen as an adaptation and not necessarily be disease-promoting will also selected Healthy Control group from the cohort. This group will be the control for changes unrelated to the diagnosis of depression or placebo/treatment effects that may be present. The exclusion criterias are: history of major depressive or anxiety disorder, current psychotic disorder, night shift worker, active suicidal ideation or psychotic symptoms, unstable general medical conditions that interfere with actigraphy acquisition, and newborns with severe health conditions.

Eligibility Criteria:
Inclusion Criteria:

* 4-6 weeks postpartum;
* Postnatal depression confirmed through Edinburgh Postnatal Depression Scale (EPDS) \&amp;gt; 10;
* Mini-International Neuropsychiatric Interview (M.I.N.I.) positive for current depressive episode.

Exclusion Criteria:

* Active suicidal ideation;
* Psychotic symptoms;
* Unstable general medical conditions that interfere with the acquisition of actigraphy;
* Newborn with severe health conditions (hospitalization, care in the neonatal ICU).