By: 16 January 2024
Perinatal depression linked to increased risk of death

Particularly due to suicide and during the first year after diagnosis, irrespective of psychiatric history

Clinically diagnosed perinatal depression is associated with an increased risk of death, particularly due to suicide and during the first year after diagnosis, finds a study published by The BMJ.

Perinatal depression was defined as any diagnosis of depression during pregnancy and up to one year after delivery and deaths were tracked over an 18-year period.

The association cannot be explained by shared family factors and is independent of pre-existing psychiatric disorders, the results show. The researchers say women who are affected, their families, and health professionals should be aware of these severe health hazards.

Perinatal depression is one of the most common complications of pregnancy, affecting up to 20% of women around delivery, but the association between perinatal depression and risk of death among affected women has not been examined.

There is also limited evidence about how factors within families, such as shared childhood experiences, might contribute to the risks of perinatal depression.

To fill these knowledge gaps, an international team of researchers set out to determine whether women with perinatal depression are at an increased risk of death compared with unaffected women and sisters.

Using Swedish national registry data from 2001 and 2018, they identified 86,551 women with a first ever diagnosis of perinatal depression and 865,510 unaffected women matched by age and calendar year at delivery.

To control for shared family factors, they also compared data for 24,473 of the women who had perinatal depression with 246,113 unaffected full sisters who delivered at least one baby during the study period.

A range of known risk factors for both depression and premature death were taken into account, including socioeconomic status, pre-existing psychiatric disorders, adverse birth outcomes, and death of a child within the first year after birth.

During the 18-year study follow-up period, 522 deaths (0.82 per 1000 person years) were reported among women with perinatal depression diagnosed at an average age of 31 years and 1,568 deaths (0.26 per 1000 person years) among unaffected women.

The results show that women with perinatal depression were more than twice as likely to die than women who did not have perinatal depression. Results were similar when comparing deaths between sisters and among women who did and did not have a pre-existing psychiatric disorder.

The increased risk associated with perinatal depression was most pronounced in the first year after diagnosis, and although it gradually reduced over time, it remained higher throughout the18 years of study follow up.

Overall, the increased risk associated with perinatal depression was greater for death caused by unnatural causes (0.46 per 1000 person years) than by natural causes (0.36 per 1000 person years).

Although suicide was rare (0.23 per 1000 person years), women with perinatal depression were more than six times as likely to die from suicide, and three times as likely to die from an accident, than women who did not have perinatal depression.

These are observational findings and the researchers point to several limitations, such as only including women who sought specialist care for their depression and possible misclassification of some suicide events as accidents.

And while they controlled for a range of factors, including those shared within families, they can’t rule out the possibility that some other unknown or unmeasured factors may have influenced their results.

They conclude: “Women affected with perinatal depression, their families, and health professionals, particularly those working in primary, maternal, and mental care, need to be aware of the serious health hazards regardless of psychiatric history. Early detection and treatment are needed for groups at high risk of perinatal depression to prevent the fatal outcomes.”

Reference: Perinatal depression and risk of mortality: nationwide, register based study in Sweden doi: 10.1136/bmj-2023-075462Journal: The BMJ

Source: The BMJ