Sympathetic Activity, Heart Failure, Obesity, and Metabolic Syndrome: Is There Any Role for Obstructive Sleep Apnea?

The incidence and strength of muscle sympathetic nerve activity (MSNA) depend on the magnitude (gain) and latency (time delay) of the arterial baroreflex control (ABR). However, the impact of metabolic syndrome (MetS) and obstructive sleep apnea (OSA) on oscillatory pattern of MSNA and time delay of the ABR of sympathetic activity is unknown. We tested the hypothesis that MetS and OSA would impair the oscillatory pattern of MSNA and the time delay of the ABR of sympathetic activity. Forty-three patients with MetS were allocated into two groups according to the presence of OSA (MetS + OSA, n = 21; and MetS − OSA, n = 22). Twelve aged-paired healthy controls (C) were also studied. OSA (apnea-hypopnea index > 15 events/h) was diagnosed by polysomnography. We recorded MSNA (microneurography), blood pressure (beat-to-beat basis), and heart rate (EKG). Oscillatory pattern of MSNA was evaluated by autoregressive spectral analysis and the ABR of MSNA (ABRMSNA, sensitivity and time delay) by bivariate autoregressive analysis. Patients with MetS + OSA had decreased oscillatory pattern of MSNA compared with MetS − OSA ( P < 0.01) and C ( P < 0.001). The sensitivity of the ABRMSNA was lower and the time delay was greater in MetS + OSA compared with MetS − OSA ( P < 0.001 and P < 0.01, respectively) and C ( P < 0.001 and P < 0.001, respectively). Patients with MetS − OSA showed decreased oscillatory pattern of MSNA compared with C ( P < 0.01). The sensitivity of the ABRMSNA was lower in MetS − OSA than in C group ( P < 0.001). In conclusion, MetS decreases the oscillatory pattern of MSNA and the magnitude of the ABRMSNA. OSA exacerbates these autonomic dysfunctions and further increases the time delay of the baroreflex response of MSNA.

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Influence of Obstructive Sleep Apnea on Mortality in Patients With Heart Failure

Yearbook of Pulmonary Disease ◽

10.1016/s8756-3452(08)70696-0 ◽

2008 ◽

Vol 2008 ◽

pp. 261-263

Author(s):

B.A. Phillips

Keyword(s):

Heart Failure ◽

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Obstructive Sleep ◽

Patients With Heart Failure

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Understanding the role of oxidative stress in the incidence of metabolic syndrome and obstructive sleep apnea

BMC Endocrine Disorders ◽

10.1186/s12902-021-00735-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Behnam Kargar ◽

Zahra Zamanian ◽

Majid Bagheri Hosseinabadi ◽

Vahid Gharibi ◽

Mohammad Sanyar Moradi ◽

...

Keyword(s):

Oxidative Stress ◽

Metabolic Syndrome ◽

Obstructive Sleep Apnea ◽

Logistic Regression ◽

Sleep Apnea ◽

International Diabetes Federation ◽

Binary Logistic Regression ◽

Stress Index ◽

Obstructive Sleep

Abstract Background Understanding the causes and risk factors of metabolic syndrome is important for promoting population health. Oxidative stress has been associated with metabolic syndrome, and also obstructive sleep apnea. These are two diseases which have common prognostic characteristics for heart disease. The aim of this study was to examine the role of oxidative stress in the concurrent presence of metabolic syndrome and obstructive sleep apnea in a working population. Methods Participants were 163 artisan bakers in Shahroud, Iran, routinely exposed to significant heat stress and other oxidative stress indicators on a daily basis as part of their work. Using a cross-sectional design, data relevant to determining metabolic syndrome status according to International Diabetes Federation criteria, and the presence of obstructive sleep apnea according to the STOP-Bang score, was collected. Analyses included hierarchical binary logistic regression to yield predictors of the two diseases. Results Hierarchical binary logistic regression showed that oxidative stress – alongside obesity, no regular exercise, and smoking – was an independent predictor of metabolic syndrome, but not obstructive sleep apnea. Participants who were obese were 28 times more likely to have metabolic syndrome (OR 28.59, 95% CI 4.91–63.02) and 44 times more likely to have obstructive sleep apnea (OR 44.48, 95% CI 4.91–403.28). Participants meeting metabolic syndrome criteria had significantly higher levels of malondialdehyde (p < 0.05) than those who did not. No difference in oxidative stress index levels were found according to obstructive sleep apnea status. Conclusions Our findings suggest that oxidative stress contributes to the onset of metabolic syndrome, and that obstructive sleep apnea is involved in oxidative stress. Whilst obesity, exercise, and smoking remain important targets for reducing the incidence of metabolic syndrome and obstructive sleep apnea, policies to control risks of prolonged exposure to oxidative stress are also relevant in occupations where such environmental conditions exist.

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