Heart rate variability as an indicator of stress in women during wartime

The impact of post-traumatic stress related to the war was analyzed in 91 women who were in Kyiv or the Kyiv region during active combat in February and March 2022. Some of the examined women had been under occupation for an extended period. In contrast, others, from May 2022 to May 2023, experienced the strong influence of war factors such as missile and artillery shelling, staying in bomb shelters, or other shelters. Due to the military actions, the examined individuals were subjected to significant stress factors, which inevitably affected their psychoemotional state. To compare, data from 79 women examined before the Russian-Ukrainian war were used as a control group. The groups of women examined before and during the war did not differ in anthropometric indicators. To understand the age-related characteristics of civilian women, they were distributed into age groups of 30-44, 45-59, and 60-74 years. ECG registration was carried out using the ECG-recorder DiaCard (Solvaig, Ukraine). The analysis of heart rate variability (HRV) was performed by application DiaCard v. 1.0.0.73. ECG measurements were taken from 10:00 a.m. to 12:00 p.m., in the supine and standing positions (5 min). The study of HRV in women during wartime and the comparison of obtained results with the pre-war period revealed that war-related stress induces changes in HRV characteristics of various types of stress. In the examined women during wartime, there is a decrease in overall HRV, primarily due to HF oscillations, indicating a reduction in parasympathetic activity of the autonomic nervous system (ANS). Such changes are typical for mild stress. Changes in HRV under conditions of military stress depend on the age of individuals and are more pronounced in young and elderly women. No significant shifts in heart rate variability were observed in individuals of average age.