Exercise training reverse autonomic dysfunction and hypertension in rats fed with high-fat diet

AIMS: We evaluated whether exercise training ameliorates cardiovascular autonomic dysfunction in obesity-induced by high-fat diet (HFD) in rats. METHODS Wistar male rats were assigned in normal diet, sedentary (ND-S) and trained (ND-T) and HFD, sedentary (HFD-S) and trained (HFD-T). Blood pressure (BP), heart rate (HR), HR variability (HRV), BP variability (BPV), cardiac baroreflex and cardiac autonomic tonus were assessed. HFD-S showed higher bodyweight increase (19.4%) compared to all other groups (HFD-T: 13.2%, ND-S: 14% and ND-T: 12.4%). Relative epididymal, retroperitoneal and visceral fat was also greater in HFD-S compared to all other groups. Resting bradycardia in ND-T (339.5±10.6 bpm) and HFD-T (341.0 ± 9.4 bpm) was more pronounced than ND-S (438.4 ± 6.3 bpm; p<0.05) and HFD-S (448.5 ± 18.7 bpm; p<0.05). The HFD-T group showed lower systolic (125.3 ( 1.9 mmHg), diastolic (88.5 ( 2.0 mmHg) and mean BP (100.3 ± 2.5 mmHg) in comparison with HFD-S (153.8 ( 3.7; 103.5 ( 2.6 and 120.5 ± 3.7 mmHg; p<0.05, respectively). Lower variance of HRV and higher variance of diastolic BPV was observed in HFD-S compared to other groups while sympathetic modulation of HRV and BPV was higher in HFD-S, as well as the LF/HF ratio. HFD-T showed a decrease in sympathetic tonus compared to HFD-S. ND-T and HFD-T showed higher cardiac vagal tonus than respective sedentary groups. Analysis showed an association between visceral fat, sympathetic activity and BP. CONCLUSIONS: HFD induces hypertension and is associated with autonomic imbalance in rats, while exercise training may reverse these harmful changes.(AU)

Cardiovascular Autonomic Dysfunction in Patients with Drug-Induced Parkinsonism

BACKGROUND AND PURPOSE: Recent studies have shown that several nonmotor symptoms differ between Parkinson's disease (PD) and drug-induced parkinsonism (DIP). However, there have been no reports on cardiovascular autonomic function in DIP, and so this study investigated whether cardiovascular autonomic function differs between PD and DIP patients. METHODS: This study consecutively enrolled 20 DIP patients, 99 drug-naïve PD patients, and 25 age-matched healthy controls who underwent head-up tilt-table testing and 24-h ambulatory blood pressure monitoring. RESULTS: Orthostatic hypotension was more frequent in patients with PD or DIP than in healthy controls. In DIP, orthostatic hypotension was associated with the underlying psychiatric diseases and neuroleptics use, whereas prokinetics were not related to orthostatic hypotension. The supine blood pressure, nighttime blood pressure, and nocturnal blood pressure dipping did not differ significantly between the DIP and control groups. Supine hypertension and nocturnal hypertension were more frequent in PD patients than in controls. CONCLUSIONS: The included DIP patients frequently exhibited orthostatic hypotension that was associated with the underlying diseases as well as the nature of and exposure time to the offending drugs. Clinicians should individualize the manifestations of DIP according to underlying diseases as well as the action mechanism of and exposure time to each offending drug.

Assessment of Cardiovascular Autonomic Function in Asymptomatic Obese Young Adults – Prevention is Better than Cure.

Back ground: Obesity is emerging global epidemic in young adults who form the productive group of the society. This has been called as new world syndrome and is a massive reflection of social, economic and cultural problems currently faced by the developing and developed countries. As cardiac autonomic dysfunction often coexists with obesity, early detection of autonomic impairment by simple investigations of autonomic function, can be potentially important to prevent future complications. Objective: To identify cardiovascular autonomic dysfunction in asymptomatic obese young adults. Study design: This study was conducted in the department of Physiology at Kakatiya Medical College, Warangal, A.P, 30 apparently healthy obese subjects of both sex with BMI > 25 kg/sqm were taken as study group. Age and sex matched 30 normal weight subjects (BMI 18.5-22.9 kg/ sqm) taken as control group. Methods: Ewing’s battery of 5 noninvasive cardiovascular reflex tests were done for assessing autonomic function. These autonomic function parameters were correlated with BMI, Unpaired Student‘t’ test and Pearson correlation coefficient test were used for statistical analysis. Results: Mean values of all cardiovascular reflex tests were significantly lower in the study group. Conclusion: The results indicate that cardiovascular autonomic dysfunction is present in otherwise healthy obese young adults.

Cardiovascular Autonomic Neuropathy in Systemic Lupus Erythematosus.

Purpose: Objective is to evaluate cardiovascular autonomic function in SLE by simple non-invasive tests. Methods: A case control study was carried out involving 18-50 yrs old previously diagnosed SLE patients and same number of age and sex-matched controls. Parasympathetic function was assessed by heart rate (HR) response to Valsalva maneuver, deep breathing and standing. Sympathetic function was evaluated by blood pressure response to standing and sustained hand-grip test (HGT). Results: There were 50 female SLE patients. They had significantly higher minimum resting HR and diastolic blood pressure (DBP). HR variation with deep breathing, expiratory inspiratory ratio, 30:15 ratio and DBP change in response to HGT were significantly lower inpatients compared to controls. Thirty patients (60%) had at least one abnormal or two borderline test results indicating autonomic impairment of which 27 had parasympathetic dysfunction and 7 had sympathetic dysfunction. Conclusion: Autonomic dysfunction is common in SLE with higher prevalence of parasympathetic impairment.