Perinatal depression has been linked to an increased risk of death

An analysis of data from nearly one million women has found that women with clinically diagnosed perinatal depression have a higher risk of death, especially within the first year of diagnosis, with suicide at the top of the list of causes of death. As reported in The BMJ, the risk of death was more than doubled.

Perinatal depression refers to a depressive disorder that occurs during pregnancy (prenatal depression) or a few weeks after delivery (postpartum depression). It is thought to occur in 10 to 20 percent of women, although some researchers say it can affect up to 25 percent of women in developing countries.

At the same time, it is known that depressive syndrome in the mother is harmful to both her and her offspring. For example, perinatal depression is associated with an increased risk of suicide, accounting for up to 20 percent of maternal deaths in the postpartum period in high-income countries. However, little is known about the overall increase in mortality in women with perinatal depression.

Chinese researchers, along with Swedish colleagues led by Qing Shen of Tongji University, investigated the association of perinatal depression with subsequent risk of death. To do so, they used the Swedish national registry of child births from 2001 to 2018. The sample included a total of 86551 women with perinatal depression (55 percent had prenatal depression and 45 percent had postnatal depression) and 865510 women in the control group.

The mean age at the time of diagnosis was 31 years; compared with women without perinatal depression, women in the study group were more likely to have given birth in Scandinavian countries, had lower levels of education and family income, and were less likely to live with the child's father. At entry to prenatal care, they were more likely to be first-time mothers and to be overweight or obese, to be smokers, and to have pre-existing psychiatric disorders. All women in the study group had at least one sibling who had given birth to at least one child.

During the follow-up period, researchers recorded 522 deaths (death rate 0.82 per 1,000 person-years) among women with perinatal depression and 1,568 deaths among healthy women (death rate 0.26 per 1,000 person-years). The primary analysis showed that women with perinatal depression had a significantly higher risk of death than healthy women (hazard ratio 3.26). After adjustment for covariates, the hazard ratio was 2.11. The relationship remained similar when comparing mortality between siblings.

Cumulative all-cause mortality increased over time in women with perinatal depression. The risk increased mainly for unnatural causes of death, with suicide leading among them, followed by accidental death. The frequency of deaths due to suicide was particularly high in the first years after diagnosis, particularly in postpartum depression. Among the natural causes of death, cancer was the leader.

This work shows that even when family factors were taken into account, women with clinically diagnosed perinatal depression had a greater statistical risk of death, especially during the first year after diagnosis and due to suicide.