RENAN SEGALLA GUERRA
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- Muscle Metaboreflex Control of Sympathetic Activity in Obstructive Sleep Apnea(2017) UENO-PARDI, Linda M.; GUERRA, Renan S.; GOYA, Thiago T.; SILVA, Rosyvaldo F.; GARA, Elisangela M.; LIMA, Marta F.; NOBRE, Thais S.; ALVES, Maria J. N. N.; TROMBETTA, Ivani C.; LORENZI-FILHO, GeraldoPurpose: Previous studies report abnormal muscle metaboreflex control of muscle sympathetic nerve activity (MSNA) in obesity, hypertension, and heart failure. We hypothesized that obstructive sleep apnea (OSA) is associated with augmented metaboreflex control of MSNA. Methods: Thirty-one sedentary individuals with no comorbidities (age = 52 +/- 1 yr, body mass index = 28 +/- 1 kg.m(-2)) without (control, n = 14) and with OSA(n = 17) defined by polysomnography, underwent echocardiography. HR, blood pressure (BP), MSNA (microneurography), and forearm blood flow measured by venous occlusion plethysmography were continuously measured 4 min at baseline, during 3 min of 30% handgrip static exercise, and during 2 min of post-handgrip muscle ischemia (PHMI). Results: Control and OSA groups were similar in age, body mass index, and ejection fraction. Baseline HR, BP, and forearm blood flow increased similarly during handgrip exercise. Blood pressure remained significantly elevated in relation to baseline during PHMI, but HR and forearm blood flow returned toward baseline during PHMI in both groups. Baseline MSNA was significantly higher in the OSA group than in controls (P < 0.05). During peak 30% static handgrip exercise, MSNA increased significantly in both control and OSA groups, but MSNA responses were higher in patients with OSA. During PHMI, MSNA in control subjects remained significantly elevated compared with that at baseline. In contrast, in patients with OSA, MSNA decreased to baseline values. A significant correlation was found between changes in MSNA due to PHMI and apnea-hypopnea index (r = -0.61, P < 0.001), and with minimum O-2 saturation (r = 0.70, P G 0.001). Conclusions: These findings suggest an association between OSA and decreased metaboreflex control of MSNA. Muscle vasodilation during handgrip static exercise is preserved in patients with OSA.
- Exercise Training Increases Metaboreflex Control in Patients with Obstructive Sleep Apnea(2019) GUERRA, Renan S.; GOYA, Thiago T.; SILVA, Rosyvaldo F.; LIMA, Marta F.; BARBOSA, Eline R. F.; ALVES, Maria Janieire De N. N.; RODRIGUES, Amanda G.; LORENZI-FILHO, Geraldo; NEGRAO, Carlos Eduardo; UENO-PARDI, Linda M.Introduction/Purpose We demonstrated that patients with obstructive sleep apnea (OSA) have reduced muscle metaboreflex control of muscle sympathetic nerve activity (MSNA). In addition, exercise training increased muscle metaboreflex control in heart failure patients. Objective We tested the hypothesis that exercise training would increase muscle metaboreflex control of MSNA in patients with OSA. Methods Forty-one patients with OSA were randomized into the following two groups: 1) nontrained (OSANT, n = 21) and 2) trained (OSAT, n = 20). Muscle sympathetic nerve activity was assessed by microneurography technique, muscle blood flow (FBF) by venous occlusion plethysmography, heart rate by electrocardiography, and blood pressure with an automated oscillometric device. All physiological variables were simultaneously assessed at rest, during isometric handgrip exercise at 30% of the maximal voluntary contraction, and during posthandgrip muscle ischemia (PHMI). Muscle metaboreflex sensitivity was calculated as the difference in MSNA between PHMI and the rest period. Patients in the OSAT group underwent 72 sessions of moderate exercise training, whereas patients in the OSANT group were clinical follow-up for 6 months. Results The OSANT and OSAT groups were similar in anthropometric, neurovascular, hemodynamic and sleep parameters. Exercise training reduced the baseline MSNA (34 2 bursts per minute vs 25 +/- 2 bursts per minute; P < 0.05) and increased the baseline FBF (2.1 +/- 0.2 mLmin(-1) per 100 g vs 2.4 +/- 0.2 mLmin(-1) per 100 g; P < 0.05). Exercise training significantly reduced MSNA levels and increased FBF responses during isometric exercise. Exercise training significantly increased MSNA responses during PHMI (6.5 +/- 1 vs -1.7 +/- 1 bursts per minute, P < 0.01). No significant changes in FBF or hemodynamic parameters in OSANT patients were found. Conclusions Exercise training increases muscle metaboreflex sensitivity in patients with OSA. This autonomic change associated with increased muscle blood flow may contribute to the increase in exercise performance in this set of patients.
conferenceObject Exercise Training Improves Metaboreflex Control of Sympathetic Nerve Activity in Obstructive Sleep Apnea(2018) GUERRA, Renan Segalla; GOYA, Thiago T.; SILVA, Rosyvaldo F.; BARBOSA, Eline R. F.; LIMA, Marta F.; LORENZI-FILHO, Geraldo; NEGRAO, Carlos Eduardo; UENO-PARDI, Linda Massako- Increased Muscle Sympathetic Nerve Activity and Impaired Executive Performance Capacity in Obstructive Sleep Apnea(2016) GOYA, Thiago T.; SILVA, Rosyvaldo F.; GUERRA, Renan S.; LIMA, Marta F.; BARBOSA, Eline R. F.; CUNHA, Paulo Jannuzzi; LOBO, Denise M. L.; BUCHPIGUEL, Carlos A.; BUSATTO-FILHO, Geraldo; NEGRAO, Carlos E.; LORENZI-FILHO, Geraldo; UENO-PARDI, Linda M.Study Objectives: To investigate muscle sympathetic nerve activity (MSNA) response and executive performance during mental stress in obstructive sleep apnea (OSA). Methods: Individuals with no other comorbidities (age = 52 +/- 1 y, body mass index = 29 +/- 0.4, kg/m(2)) were divided into two groups: (1) control (n = 15) and (2) untreated OSA (n = 20) defined by polysomnography. Mini-Mental State of Examination (MMSE) and Inteligence quocient (IQ) were assessed. Heart rate (HR), blood pressure (BP), and MSNA (microneurography) were measured at baseline and during 3 min of the Stroop Color Word Test (SCWT). Sustained attention and inhibitory control were assessed by the number of correct answers and errors during SCWT. Results: Control and OSA groups (apnea-hypopnea index, AHI = 8 +/- 1 and 47 +/- 1 events/h, respectively) were similar in age, MMSE, and IQ. Baseline HR and BP were similar and increased similarly during SCWT in control and OSA groups. In contrast, baseline MSNA was higher in OSA compared to controls. Moreover, MSNA significantly increased in the third minute of SCWT in OSA, but remained unchanged in controls (P < 0.05). The number of correct answers was lower and the number of errors was significantly higher during the second and third minutes of SCWT in the OSA group (P < 0.05). There was a significant correlation (P < 0.01) between the number of errors in the third minute of SCWT with AHI (r = 0.59), arousal index (r = 0.55), and minimum O-2 saturation (r = -0.57). Conclusions: As compared to controls, MSNA is increased in patients with OSA at rest, and further significant MSNA increments and worse executive performance are seen during mental stress.
- Exercise training reduces sympathetic nerve activity and improves executive performance in individuals with obstructive sleep apnea(2021) GOYA, Thiago Tanaka; FERREIRA-SILVA, Rosyvaldo; GARA, Elisangela Macedo; GUERRA, Renan Segalla; BARBOSA, Eline Rozaria Ferreira; TOSCHI-DIAS, Edgar; CUNHA, Paulo Jannuzzi; NEGRAO, Carlos Eduardo; LORENZI-FILHO, Geraldo; UENO-PARDI, Linda MassakoOBJECTIVE: To investigate the effects of exercise training (ET) on muscle sympathetic nerve activity (MSNA) and executive performance during Stroop Color Word Test (SCWT) also referred to as mental stress test. METHODS: Forty-four individuals with obstructive sleep apnea (OSA) and no significant co-morbidities were randomized into 2 groups; 15 individuals completed the control period, and 18 individuals completed the ET. Mini-mental state of examination and intelligence quotient were also assessed. MSNA assessed by microneurography, heart rate by electrocardiography, blood pressure (automated oscillometric device) were measured at baseline and during 3 min of the SCWT. Peak oxygen uptake (VO2 peak) was evaluated using cardiopulmonary exercise testing. Executive performance was assessed by the total correct responses during 3 min of the SCWT. ET consisted of 3 weekly sessions of aerobic exercise, resistance exercises, and flexibility (72 sessions, achieved in 40 +/- 3.9 weeks). RESULTS: Baseline parameters were similar between groups. Heart rate, blood pressure, and MSNA responses during SCWT were similar between groups (p>0.05). The comparisons between groups showed that the changes in VO2 (4.7 +/- 0.8 vs -1.2 +/- 0.4) and apnea-hypopnea index (-7.4 +/- 3.1 vs 5.5 +/- 3.3) in the exercise-trained group were significantly greater than those observed in the control group respectively (p<0.05) after intervention. ET reduced MSNA responses (p<0.05) and significantly increased the number of correct answers (12.4%) during SCWT. The number of correct answers was unchanged in the control group (p>0.05). CONCLUSIONS: ET improves sympathetic response and executive performance during SCWT, suggesting a prominent positive impact of ET on prefrontal functioning in individuals with OSA. ClinicalTrials.gov: NCT002289625.
- Effects of exercise training on autonomic modulation and mood symptoms in patients with obstructive sleep apnea(2021) ARAUJO, C. E. L.; FERREIRA-SILVA, R.; GARA, E. M.; GOYA, T. T.; GUERRA, R. S.; MATHEUS, L.; TOSCHI-DIAS, E.; RODRIGUES, A. G.; BARBOSA, E. R. F.; FAZAN JR., R.; LORENZI-FILHO, G.; NEGRAO, C. E.; UENO-PARDI, L. M.We evaluated the effects of exercise training (ET) on the profile of mood states (POMS), heart rate variability, spontaneous baroreflex sensitivity (BRS), and sleep disturbance severity in patients with obstructive sleep apnea (OSA). Forty-four patients were randomized into 2 groups, 18 patients completed the untrained period and 16 patients completed the exercise training (ET). Beat-to-beat heart rate and blood pressure were simultaneously collected for 5 min at rest. Heart rate variability (RR interval) was assessed in time domain and frequency domain (FFT spectral analysis). BRS was analyzed with the sequence method, and POMS was analyzed across the 6 categories (tension, depression, hostility, vigor, fatigue, and confusion). ET consisted of 3 weekly sessions of aerobic exercise, local strengthening, and stretching exercises (72 sessions, achieved in 40 +/- 3.9 weeks). Baseline parameters were similar between groups. The comparisons between groups showed that the changes in apnea-hypopnea index, arousal index, and O-2 desaturation in the exercise group were significantly greater than in the untrained group (P < 0.05). The heart rate variability and BRS were significantly higher in the exercise group compared with the untrained group (P < 0.05). ET increased peak oxygen uptake (P < 0.05) and reduced POMS fatigue (P < 0.05). A positive correlation (r=0.60, P < 0.02) occurred between changes in the fatigue item and OSA severity. ET improved heart rate variability, BRS, fatigue, and sleep parameters in patients with OSA. These effects were associated with improved sleep parameters, fatigue, and cardiac autonomic modulation, with ET being a possible protective factor against the deleterious effects of hypoxia on these components in patients with OSA.