The effect of obstructive sleep apnea therapy on cardiovascular autonomic function: a systematic review and meta-analysis

Abstract

Study Objectives Autonomic function is impaired in obstructive sleep apnea (OSA) and may mediate the association between OSA and cardiovascular risk. We investigated the effect of OSA therapy on autonomic function through a systematic review and meta-analysis of intervention studies. Methods A systematic search using three databases (Medline, Embase, and Scopus) was performed up to December 9, 2020. Studies of OSA patients ≥ 18 years with autonomic function assessed before and after treatment with positive airway pressure, oral appliance, positional therapy, weight loss, or surgical intervention were included for review. Random effects meta-analysis was carried out for five groups of autonomic function indices. Risk of bias was assessed using the Cochrane Collaboration tool. Results Forty-three eligible studies were reviewed with 39 included in the meta-analysis. OSA treatment led to large decreases in muscle sympathetic nerve activity (Hedges’ g = −1.08; 95% CI −1.50, −0.65, n = 8) and moderate decreases in catecholamines (−0.60; −0.94, −0.27, n = 3) and radio nucleotide imaging (−0.61; −0.99, −0.24, n = 2). OSA therapy had no significant effect on baroreflex function (Hedges’ g = 0.15; 95% CI −0.09, 0.39, n = 6) or heart rate variability (0.02; −0.32, 0.36, n = 14). There was a significant risk of bias due to studies being primarily non-randomized trials. Conclusions OSA therapy selectively improves autonomic function measures. The strongest evidence for the effect of OSA therapy on autonomic function was seen in reduced sympathetic activity as assessed by microneurography, but without increased improvement in parasympathetic function. OSA therapy may reduce the risk of cardiovascular disease in OSA through reduced sympathetic activity.

Obstructive sleep apnea heterogeneity and autonomic function: a role for heart rate variability in therapy selection and efficacy monitoring

“…However, a key gap in existing HRV analysis is that there are no reference values and the combination of HRV metrics to determine clinically significant autonomic dysfunction in the OSA population, thus limiting their generalisability towards monitoring treatment efficacy in clinical practice (Dissanayake et al, 2022). The attempt to estimate standard short‐term and long‐term HRV norms stratified by age and sex would accelerate the application of HRV.…”

“…Summarised findings of included studies in terms of HRV in treatments for OSA are shown in Table 1. A recent meta-analysis found that the differences of autonomic modulation assessed by HRV including global, sympathetic, and parasympathetic HRV did not reach statistical significance before and after OSA treatment, but OSA treatment can reduce sympathetic activity as measured by muscle sympathetic nerve activity (Dissanayake et al, 2022). This discrepancy may result from poor control of the condition, affecting HRV measurement, and various methods of signal processing and analysis across studies.…”

“…The commonly used HRV metrics are shown in TableS1. Any of the linear and non-linear variables allow detection of changes in the physiological basis of neurogenic autonomic control and provide information hidden in variations of the cardiac rhythm(Shaffer & Ginsberg, 2017;Ucak et al, 2021).However, a key gap in existing HRV analysis is that there are no reference values and the combination of HRV metrics to determine clinically significant autonomic dysfunction in the OSA population, thus limiting their generalisability towards monitoring treatment efficacy in clinical practice(Dissanayake et al, 2022). The attempt to estimate standard short-term and long-term HRV norms stratified by age and sex would accelerate the application of HRV.…”

Established and potential cardiovascular risk factors in metabolic syndrome: Effect of bariatric surgery

“…Other nonlipoprotein biomarkers of metabolic syndrome are summarized in Table 2[83–90,91 ▪ ,92,93–100,101 ▪ ,102,103–107].…”

Chronic intermittent hypoxia remodels catecholaminergic nerve innervation in mouse atria

“…This is associated with autonomic dysregulation expressed as increased sympathetic discharge and a shift in heart rate variability from high to low‐frequency bands (related to sympathetic overactivity) (Floras & Ponikowski, 2015). Recent studies have shown that OSA therapy improved autonomic function measures, which may reduce the risk CVD through decreased sympathetic activity (Barthelemy et al., 2022; Dissanayake et al., 2022). These observations further reinforce the major role of excessive sympathetic activity in the pathogenesis of OSA and its associated end‐organ morbidities.…”