A study published in the European Heart Journal finds that women with perinatal depression are at higher risk of developing cardiovascular disease in middle adulthood.
Study: Perinatal depression and risk of maternal cardiovascular disease: a Swedish nationwide study. Image Credit: christinarosepix / Shutterstock
Background
The prevalence of cardiovascular disease is sharply increasing worldwide mainly because of the widespread changes in lifestyle behaviors, including unhealthy dietary habits and lack of physical activity.
Hyperlipidemia, diabetes, obesity, and smoking are considered significant risk factors for cardiovascular disease in both men and women. Certain pregnancy-related complications, including miscarriage, pre-term birth, stillbirth, preeclampsia, and gestational diabetes, have recently been identified as female-specific risk factors for cardiovascular disease.
Many of these pregnancy-related risk factors are associated with the risk of developing perinatal depression, which is defined as a depressive episode occurring during pregnancy or after giving birth.
Existing literature has shown a bidirectional association between major, non-perinatal depression and cardiovascular disease. Antepartum (the time period before childbirth) depression has also been linked to short-term risk of cardiovascular disease.
In this study, scientists have investigated the relationship between perinatal depression and long-term risk of cardiovascular disease in Swedish women.
Study design
The scientists identified a total of 878,595 women with 1,347,032 pregnancies from the Swedish Medical Birth Register who gave birth during 2001–2014 in Sweden. They analyzed the medical history of these women to identify women with first-ever perinatal depression as well as unaffected women.
The analysis led to the identification of 55,539 women with perinatal depression and 545,567 unaffected women. Both affected and unaffected women were individually matched on age and year of conception or delivery. All women were followed up to 2020.
The association between perinatal depression and long-term cardiovascular disease risk was determined after adjusting for potential confounding factors, including demographic characteristics, smoking habits, body mass index (BMI), presence of preeclampsia, diabetes, or other psychiatric disorders, and adverse pregnancy outcomes.
Important observations
The analysis of baseline characteristics revealed that women with perinatal depression are more likely to be married and have lower educational attainment, pre-pregnancy smoking habits, a history of depression, and pre-term or C-section delivery, as compared to unaffected women.
A total of 3,533 and 20,202 cases of cardiovascular disease were detected in women with and without perinatal depression, respectively, during the study follow-up period of up to 20 years.
The analysis conducted after adjusting for potential confounding factors revealed that women with perinatal depression have a 36% higher risk of developing cardiovascular disease compared to unaffected women.
A separate analysis involving a sibling-matched cohort was conducted in the study to address unmeasured confounding factors, including genetic and familial environmental factors. The findings showed a 44% attenuated but statistically significant association between perinatal depression and cardiovascular disease risk.
Further analysis revealed that the risk of cardiovascular disease due to perinatal depression was higher among women with a history of depression or other psychiatric disorders compared to those without such a history.
Considering depression developed beyond one year postpartum (after childbirth), an increased risk of cardiovascular disease was observed in women with no subsequent depression.
Among other risk factors, gestational diabetes was found to increase the risk of cardiovascular disease due to perinatal depression.
The analysis considering various subtypes of cardiovascular disease showed that perinatal depression is the strongest risk factor for hypertensive disease, ischemic heart disease, and heart failure.
The association of perinatal depression with ischemic heart disease and heart failure was more prominent in women with antepartum depression than those with postpartum depression. The associations with other cardiovascular disease subtypes were more prominent in women with postpartum depression.
Considering the timing of perinatal depression diagnosis, the highest risk of cardiovascular disease was observed in women who were diagnosed with perinatal depression 4-6 months postpartum.
Considering the time since diagnosis, the highest risk of cardiovascular disease was observed 1-4 years after diagnosis of perinatal depression.
Study significance
The study finds that women with clinically diagnosed perinatal depression are at 36% higher risk of developing cardiovascular disease in middle adulthood. This association is stronger for postpartum depression than for antepartum depression.
The scientists hypothesize that genetic factors and familial environmental factors (childhood maltreatment) may contribute to the observed association between perinatal depression and cardiovascular disease risk.
The study could not include perinatal depression diagnosed after 2014, perinatal depression diagnosed in primary care without prescription of antidepressants, and women with perinatal depression symptoms who did not seek healthcare service. This might lead to misclassification of women with perinatal depression as unaffected women and subsequent attenuation of the observed associations.
The study included secondary diagnoses of cardiovascular disease, which are less validated. This might lead to misclassification of the disease. Moreover, the mean age of study participants was 41 years at the end of the study period, before the peak age of CVD in Sweden.
Future studies with longer follow-ups are needed to determine the impact of perinatal depression on the risk of cardiovascular disease in late adulthood.
Overall, the study findings suggest that the occurrence of perinatal depression should be considered in cardiovascular disease risk assessment in women.
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