Cardiac Sympathetic Dominance and Systemic Inflammation in COPD

Abstract

Cardiac autonomic dysfunction is an independent determinant of adverse outcomes in many diseases. The available literature on the relative changes in sympathetic and parasympathetic components in chronic obstructive pulmonary disease (COPD) is equivocal, the clinical and physiological correlates are poorly defined and association with markers of systemic inflammation has not been explored. As both autonomic dysfunction and systemic inflammation may contribute to cardiovascular morbidity in COPD, we hypothesized that these may be associated. Sixty three stable patients of COPD and 36 controls underwent spirometry, estimation of diffusion capacity, six-minute walk test and measurements of serum interleukin-6 (IL-6) and high-sensitivity C-Reactive protein. Cardiac autonomic activity was evaluated by standard five-minute heart rate variability (HRV) recordings to obtain time- and frequency-domain indices and the averaged heart rate. We observed that HRV indices of overall autonomic modulation, the standard deviation of time intervals between consecutive normal beats (SDNN) and total power, were greater in patients with higher levels of indices of both parasympathetic and sympathetic activity. The heart rate was significantly higher in patients indicating an overall sympathetic dominance and was inversely correlated with diffusion capacity. Serum IL-6 was inversely correlated with pNN50, an index of parasympathetic activity, and positively with LF/HF ratio, a measure of sympathetic: parasympathetic balance. None of the HRV indices was significantly correlated with physiological measures of severity. It was concluded that patients with COPD have increased cardiac autonomic modulation with sympathetic dominance. This is associated with decreased lung diffusion capacity and systemic inflammation.

Is cardiac autonomic modulation during upper limb isometric contraction and Valsalva maneuver impaired in COPD patients?

“…These results may be explained by augmented muscle metaboreflex activation that could occur in those patients at a more severe stage of COPD 22. This mechanism, associated with systemic inflammation present in COPD, may contribute to augmented sympathetic responses to exercise 16. Our results confirm the importance of applying the IC maneuver, which has been widely used for risk assessment in cardiovascular disease patients, as a powerful tool to assess the severity of the disease in this population 22…”

“…In addition, these HRV attenuated responses seem to be related to respiratory muscle weakness 12. Other studies, however, showed that impaired responses during exercise in these patients may be partially explained by bronchoconstriction, hypoxemia, hypercapnia, and systemic inflammation 9,13–16…”

Influence of expiratory positive airway pressure on cardiac autonomic modulation at rest and in submaximal exercise in COPD patients

“…The control of the autonomic nervous system (ANS) of patients with chronic obstructive pulmonary disease (COPD) is influenced by the sympathetic and parasympathetic systems, peripheral oxygen saturation (SpO 2 ), pulmonary stretch baroreceptors, and cardiac and pulmonary reflexes ( 1 – 3 ). In COPD patients the sympatho-vagal imbalance is caused by alterations in the ANS ( 4 ), as well as by the bronchoconstriction mechanism, hypoxia, hypercapnia, and systemic inflammation ( 3 , 5 , 6 ), resulting in a higher risk of morbimortality ( 7 ).…”

Obesity as an additional factor for autonomic imbalance and poor sleep behavior in chronic obstructive pulmonary disease: a case-control study

“…Chronic obstructive pulmonary disease (COPD) is a chronic disease strongly associated with severe morbidity and is currently the third leading cause of death globally (1). Patients with COPD display airway inflammation and destruction of the lung parenchyma, mainly due to redox imbalance and proinflammatory cytokines (2). These changes induce small airway dysfunction limiting the flow and typically present symptoms such as cough and progressive chronic dyspnea, which are limiting conditions for patients (3).…”