Perinatal depression raises risk of death in women

Women who have been clinically diagnosed with perinatal depression are at greater risk of death, particularly during the first year of diagnosis and due to an unnatural death, such as suicide, reports a study. The observed association exists independent of psychiatric history and familiar factors.

“Women affected by 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,” the researchers said. “Early detection and treatment are needed for groups at high risk of perinatal depression to prevent the fatal outcomes.”

This study used the Swedish national registers between 1 January 2001 and 31 December 2018 to identify women with a first ever diagnosis of perinatal depression confirmed via specialized care and use of antidepressants. A total of 86,551 women diagnosed with perinatal depression were matched to 865,510 individuals who did not have depression based on age and calendar year at delivery.

The researchers addressed familial confounding factors by comparing 270,586 full sisters with perinatal depression (n=24,473) and full sisters without the disorder (n=246,113), who gave at least one singleton birth during the study period.

Death due to any cause was the primary outcome, while cause-specific deaths (ie, natural and unnatural causes) were secondary. Hazard ratios (HRs) of mortality were estimated using multivariable Cox regression, considering multiple confounders. The researchers also analysed the temporal patterns of perinatal depression and differences between antepartum and postpartum onset.

Overall, 522 deaths (0.82 per 1,000 person-years) occurred among women with perinatal depression (median age 31.0 years) over 18 years of follow-up. [BMJ 2024;384:e075462]

Women with perinatal depression had an increased mortality risk (adjusted HR, 2.11, 95 percent confidence interval [CI], 1.86‒2.40) compared with those without perinatal depression. Similar associations were seen among women who had and did not have pre-existing psychiatric disorder.

Postpartum depression

Notably, this mortality risk appeared to be higher for postpartum (HR, 2.71, 95 percent CI, 2.26‒3.26) than for antepartum depression (HR, 1.62, 95 percent CI, 1.34‒1.94). This association was also observed for perinatal depression in the sibling comparison (HR, 2.12, 95 percent CI, 1.16‒3.88).

The association between perinatal depression and mortality was most evident during the first year of diagnosis. However, such risk had persisted up to 18 years since the start of follow-up.

Additionally, the risk increase correlated with both natural (HR, 1.38, 95 percent CI, 1.16‒1.64) and unnatural (HR, 4.28, 95 percent CI, 3.44‒5.32) causes of death among women with perinatal depression. Unnatural causes were higher, particularly for suicide (HR, 6.34, 95 percent CI, 4.62‒8.71). However, suicide cases were rare (0.23 per 1,000 person-years).

“In line with previous studies reporting a twofold to fivefold increase in mortality in women with postpartum psychiatric disorders, our results showed that women with postpartum depression had an almost threefold increased risk of mortality,” the researchers said. [Am J Psychiatry 2016;173:635-642; Br J Psychiatry 1998;173:209-211; Acta Psychiatr Scand 2020;142:467-475]

“This finding was not surprising because depression is one of the most common psychiatric disorders in the postpartum period,” they added. [Clin Obstet Gynecol 2012;55:788-797]