Sleep restriction progress to cardiac autonomic imbalance

Abstract

Previous studies have shown that night shift work is thought to be a risk factor for cardiovascular disease and inadequate sleep is a common feature of night shift work. Since it's more difficult to maintain adequate sleep duration among night watchmen during their working schedule, hence the purpose of our present study was to investigate whether mental stress or fatigue over restricted sleep period in night shift, affects HRV, in order to elucidate on cardiac autonomic modulation among nigh watchmen. With the purpose of this, autonomic activity determined from the levels of the heart rate variability (HRV), and also measured, body mass index (BMI), body fat percentage from skin fold thickness (biceps, triceps, and sub-scapular, supra-iliac) among normal sleep watchmen) (n = 28) and restricted sleep watchmen (n = 28) at first (1st) day, fourth (4th) day and seventh (7th) day of restricted sleep period. We observed that among restricted sleep individuals, sleepiness was significant increase at 4th day and 7th day when compare to normal sleep individuals, and, there was significant increase in, mean NN, VLF, LF, LF(nu), LF/ HF AND significant decrease in SDNN, RMSSD, TSP, HF, and HF(nu) at 4th and 7th day of restricted sleep period. In addition to, this variable was more significant increase on 7th day, when compare with 4th day. As well as there was significant negative correlation between LF(nu) and HF(nu) at subsequent 4th day [r (48) = À0.84; P = 0.01] and 7th day[r (48) = À0.95; P = 0.01] of restricted sleep period. However we didn't observe any significant variation in BMI, and body fat percentage among restricted sleep individuals when compare to normal sleep individuals with in this restricted sleep periods. Hence we concluded that partial sleep loss may cause autonomic imbalance represented by increased sympathetic and decreased parasympathetic activity; as revealed by altered HRV indices observed in this study.

The association between sleep duration and muscle sympathetic nerve activity

“…Our results support findings from previous studies that show elevated sympathetic activity in experimental sleep-restricted conditions [ 8 , 10 , 29 ]. Although no significant differences in BI were observed, it is important to note that changes in MSNA can be observed when expressed as either measure [ 30 ].…”

Effects of Sleep Deprivation on the Tryptophan Metabolism

“… 22 While chronic sleep deprivation in young, healthy volunteers increases appetite and energy consumption, activates immune system and sympathetic tone; it decreases parasympathetic tone. 23 , 24 Increased blood pressure, cortisol levels, and blood glucose levels are reported to be associated with chronic sleep restricted individuals. 25 , 26 Sleep restores the brain energy during active waking 27 and clears the metabolic waste from the central nervous system by regulating glymphatic system.…”

O Impacto Da Modernidade: A Mudança Dos Hábitos E Estilos De Vida E Suas Consequências Na Saúde Individual E Coletiva

“…Os relógios periféricos estão em cada um dos tipos de células cardiovasculares modulando as principais funções como frequência cardíaca, pressão arterial, catecolaminas circulantes, marcadores de coagulação sanguínea e funções endoteliais vasculares (MENTZE-LOU et al, 2023). Ao direcionar o foco na frequência cardíaca, é importante ressalta que ela é regulada pelo sistema nervoso simpático e parassimpático (CHOUDHARY et al, 2018/ XU et al, 2023. Há ensaios clínicos que apontam a relação da privação do sono com o enfraquecimento do sistema nervoso autônomo e a alteração da estabilidade do sistema cardiovascular (XU et al, 2023).…”

“…A perda de sono pode alterar, também, a resposta do sistema simpático-adreno medular (CHOUDHARY et al, 2018) e do eixo hipotálamo-hipófise-adrenocortical e prejudicar o ramo autonômico do sistema de reposta ao estresse (CHOUDHARY et al, 2018/ CABEZA DE BACA et al, 2019. O cortisol e outros glicocorticoides estão envolvidos nos ciclos de sono-vigília.…”

“…O sono curto produz desregulação do eixo hipotálamo-hipófise-adrenal, resultando em estados de "vigilân-cia", os quais podem produzir mais alterações no sono (CABEZA DE BACA et al, 2019). Dessa forma, ao analisar a fisiopatologia da privação do sono nas alterações cardiovasculares até agora abordada, conclui-se que a ativação simpática é considerada como o principal mecanismo envolvido no desenvolvimento de doenças cardiovasculares associadas ao comprometimento do sono (CHOUDHARY et al, 2018).…”