Autonomic nervous system activity and anxiety and depressive symptoms in mothers up to 2 years postpartum

Abstract

Introduction: We investigated the association between autonomic nervous system (ANS) activity and symptoms of anxiety and depression for the first 2 years postpartum.

Methods: A total of 108 participants within 2 years postpartum underwent physiological measurements of ANS activity using the heart rate variability (HRV) power spectrum and self-reported questionnaires (14-item Hospital Anxiety and Depression Score). The cutoff points for anxiety and depressive symptom scores in this questionnaire were as follows: 7 or less, non-cases; 8–10, doubtful cases; 11 or more, definite cases. This study was conducted from 2012 to 2014 at University Hospital in Kyoto Prefectural University of Medicine and a nearby obstetrics and gynecology department clinic in Japan.

Results: Anxiety and depression non-cases accounted for 67.6% (n = 73) of subjects, anxiety non-cases and depression doubtful and definite cases 7.4% (n = 8), anxiety doubtful and definite cases and depression non-cases 8.3% (n = 9), and anxiety and depression doubtful and definite cases 16.7% (n = 18). Findings were similar for women with anxiety or depression, with total power (TP), low-frequency (LF) and high-frequency (HF) components of HRV among doubtful and definite cases significantly lower than among non-cases for both anxiety (p = 0.006, 0.034, 0.029, respectively) and depression (p = 0.001, 0.004, 0.007). Significant correlations were observed between TP, LF and HF and anxiety and depression scores (respective values for anxiety: r_s= −0.331, p <0.001; r_s = −0.286, p = 0.003; r_s = −0.269, p = 0.005; and depression: r_s = −0.389, r_s = −0.353, r_s = −0.337, all p <0.001).

Discussion: The present study demonstrated that mothers with anxiety or depressive symptoms had significantly lower HRV (HF, LF and TP) than those without.

• Anxiety
• autonomic nervous system
• depression
• postpartum

Current knowledge on this subject

• The prevalence of depression is 5%, but that of postpartum depression ranges from 6.5% to 12.9%. Worldwide, <50% of individuals with depression receive proper treatment.

• Common screening instruments such as the Hospital Anxiety and Depression Score and Edinburgh Postnatal Depression Scale generally provide subjective data regarding anxiety and depressive symptoms. However, the power spectrum of heart rate variability (HRV) can provide objective data for analyzing autonomic mechanisms.

• Subjects with major depression disorder or generalized anxiety disorder demonstrate lower HRV than healthy subjects.

What this study adds

Mothers with anxiety or depressive symptoms had significantly lower HRV (high-frequency, low-frequency and total power) than those without symptoms. However, the implications of these results for clinical practice are unclear at this time, and further examination of their significance in clinical practice is required.