Cardiovascular autonomic function and baroreflex sensitivity in drug-resistant temporal lobe epilepsy.

OBJECTIVE: Temporal lobe epilepsy (TLE) is often associated with autonomic manifestations. Sudden unexpected death in epilepsy (SUDEP) is a leading cause of mortality in epilepsy. Cardiac disturbances and autonomic dysfunction are the potential mechanisms behind SUDEP. Though heart rate variability (HRV) and autonomic function tests are well studied in drug-resistant temporal lobe epilepsy, there is a paucity of data on baroreflex sensitivity (BRS), a better marker of cardiac mortality in this population. We aimed to study the interictal cardiac autonomic function and BRS in people living with drug-resistant temporal lobe epilepsy compared to healthy controls. MATERIALS AND METHODS: Thirty drug-resistant temporal lobe epilepsy (TLE) individuals and thirty healthy volunteers were recruited. Heart rate variability at rest, heart rate and blood pressure (BP) at rest, during deep breathing, postural change, BP response to isometric handgrip exercise, and baroreflex sensitivity were recorded in all study participants. The results were analyzed and compared between the two groups. RESULTS: Compared to controls, the resting heart rate, HRV, parasympathetic reactivity test, and BRS significantly differed in people living with drug-resistant TLE. Time-domain indices including SDNN (p < 0.001), RMSSD (p < 0.001), NN50 (p < 0.001), and pNN50 (p < 0.001) were significantly reduced in the patients compared to controls. In frequency-domain indices, the total power was reduced (p < 0.001) in drug-resistant TLE. The parasympathetic reactivity such as changes in heart rate during deep breathing (E: I) (p < 0.02) and postural change (30:15) (p < 0.005) were significantly reduced in the patients. Baroreflex sensitivity was also significantly reduced in the drug-resistant TLE group (p < 0.001). CONCLUSION: The present study findings are suggestive of parasympathetic dysfunction in drug-resistant TLE. Reduced HRV and BRS may increase the risk of SUDEP in people living with epilepsy.

Decreased baroreflex sensitivity is associated with cardiometabolic risks and prehypertension status in early-postmenopausal women.

OBJECTIVE: We studied the link of decreased baroreflex sensitivity (BRS) to cardiometabolic risks and prehypertension status in postmenopausal women during their early menopausal phase. METHODS: Premenopausal women (n = 55) and early-postmenopausal women (n = 50) of age group between 40 and 55 years were recruited for the study, and their anthropometric parameters, complete battery of autonomic function tests (AFT), BRS, hormone levels, and cardiometabolic risk parameters were measured and compared between two groups. Correlation analysis of BRS with various physiological and biochemical parameters in these two groups were performed. Multiple regression analysis of BRS with various other associated factors in postmenopausal subjects and bivariate logistic regression analysis for assessing prediction of prehypertension status by BRS in postmenopausal group were performed. RESULTS: There was a significant difference in AFT and metabolic parameters between premenopausal and postmenopausal women. Sympathovagal imbalance (increased sympathetic and decreased parasympathetic) was prominent in early-postmenopausal women. Decreased BRS, the marker of cardiovascular (CV) risk was found to be significant (P < .001) and correlated with various cardiometabolic parameters in early-postmenopausal subjects. Multiple regression analysis demonstrated that decreased BRS is independently linked to parameters of decreased vagal activity, inflammation, and oxidative stress in early-postmenopausal group. Decreased BRS could predict prehypertension status in early-postmenopausal subjects as confirmed by bivariate logistic regression analysis. CONCLUSION: Sympathovagal imbalance, decreased BRS and considerable metabolic derangements were observed in women in their early phase of menopause. Decreased BRS appears to be associated with the cardiometabolic risks in these women. Prehypertension status in early-postmenopausal subjects could be predicted by decreased BRS.

Effects of Three Months of Honey Supplementation on Quality of Life and Neuropathy in Type 2 Diabetic Patients.

CONTEXT: Diabetic neuropathy, a common debilitating complication of type 2 diabetes, can occur despite adequate treatment. To date, no studies have occurred on the use alternative medicine as an adjunct therapy for treating diabetic neuropathy. OBJECTIVE: The study assessed the effects of three months of honey supplementation on insulin resistance, lipid profiles, oxidant status, nerve conduction, and QOL in patients with diabetic neuropathy. METHODS/DESIGN: The research team designed a single-arm, open-label pilot study. SETTING: The study took place at the Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER) in Puducherry, India. PARTICIPANTS: The study included 48 patients with diabetic neuropathy at the institute, with a mean age of 58.91 ± 7.976 years. INTERVENTION: Participants took honey for three months at a dose of 0.5 gm/Kg of body weight per day. OUTCOME MEASURES: Participants completed the Neuropathy Total Symptom Score-6 (NTSS-6) questionnaire and the Norfolk QOL Diabetic Neuropathy (Norfolk QOL-DN) questionnaire at baseline and postintervention. Also, participants' glucose levels, lipid profiles, and biochemical markers were obtained and a nerve conduction study was completed at baseline and postintervention. RESULTS: A significant reduction occurred in the NTSS-6 score (P < .0001) and the Norfolk QOL-DN total score (P < .0001) from baseline to postintervention. Participants' fasting blood glucose (FBG), triglycerides (TG), and total cholesterol (TC) decreased significantly, at P = .0192, P = .0371, and P = .0049, respectively. Their malondialdehyde (MDA), and inflammatory markers interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) also decreased significantly, and MDA showed a significant correlation with neuron specific enolase (NSE). CONCLUSIONS: Three months honey supplementation reduced participants' subjective pain scores and symptoms from diabetic neuropathy and improved their QOL. However, the nerve conduction study showed that no significant change had occurred in motor velocity.

Contribution of insulin resistance to decreased baroreceptor sensitivity & cardiometabolic risks in pre-obesity & obesity.

BACKGROUND & OBJECTIVES: Although insulin resistance (IR) is a known complication in obesity, the physiological mechanisms linking IR with cardiometabolic risks in obesity have not been well studied. This study was conducted to assess the difference in cardiovascular (CV) risk profile in IR and non-IR (NIR) conditions, and contribution of IR to cardiometabolic risks in pre-obese and obese individuals. METHODS: Basal CV, blood pressure variability, autonomic function test and cardiometabolic parameters were recorded in pre-obese (n=86) and obese (n=77) individuals during 2012 and 2015. The association of altered cardiometabolic parameters with homeostatic model for IR (HOMA-IR) in pre-obese and obese groups and with baroreceptor sensitivity (BRS) in IR and NIR groups was calculated by appropriate statistical analysis. RESULTS: Decreased BRS, a known CV risk and cardiometabolic parameters were significant in IR (pre-obese and obese) group compared to the NIR group. Sympathovagal imbalance in the form of increased sympathetic and decreased parasympathetic activities was observed in individuals with IR. There was no significant difference in the level of independent contribution of HOMA-IR to cardiometabolic parameters in pre-obese and obese groups. Adiponectin and inflammatory markers had an independent contribution to BRS in IR group. INTERPRETATION & CONCLUSIONS: Findings of the present study demonstrated that the intensity of cardiometabolic derangements and CV risk were comparable between IR, pre-obese and obese individuals. Pro-inflammatory state, dyslipidaemia and hypoadiponectinaemia might contribute to CV risk in these individuals with IR. IR could possibly be the link between altered metabolic profile and increased CV risks in these individuals independent of the adiposity status.

Decreased baroreflex sensitivity is linked to the atherogenic index, retrograde inflammation, and oxidative stress in subclinical hypothyroidism.

Purpose/aim of the study: The present study investigated the link of hyperlipidemia, inflammation and oxidative stress (OS) to cardiovascular (CV) risks in subclinical hypothyroidism (SCH). MATERIALS AND METHODS: We enrolled 81 subclinical hypothyroid patients and 80 healthy subjects as control. Their CV and autonomic functions were assessed by spectral analysis of heart rate variability (HRV), continuous blood pressure variability (BPV) measurement and conventional autonomic function testing. Thyroid profile, lipid profile, immunological, inflammatory and OS markers were estimated and correlated with the baro-reflex sensitivity (BRS), the marker of sympathovagal imbalance (SVI) & CV risk. RESULTS: Mean arterial pressure (MAP, P<0.0001), total peripheral resistance (TPR, P<0.0001), ratio of low-frequency to high-frequency power of HRV (LF-HF ratio) (P<0.0001) were significantly higher and BRS (P<0.0001) was significantly lower in SCH group than the control group. BRS significantly correlated with heart rate, MAP, LF-HF ratio, lipid risk factors, anti-thyroperoxidase antibody, thyroid-stimulating hormone, high-sensitive C-reactive protein (hsCRP), malondialdehyde (MDA) and SCH. CONCLUSIONS: It was concluded that SVI is associated with SCH. Though dyslipidemia, inflammation and OS contributed to decreased BRS, SCH per se contributed maximally to it. Decreased BRS could be a physiological basis of increased CV risks in patients with SCH.

Decreased baroreflex sensitivity is linked to sympathovagal imbalance, low-grade inflammation, and oxidative stress in pregnancy-induced hypertension.

Pregnancy-induced hypertension (PIH) has been reported as a cardiovascular (CV) risk. We assessed the sympathovagal imbalance (SVI) and the association of inflammation and oxidative stress (OS) with CV risks in PIH. A total of 125 pregnant women having a risk factor for PIH were followed till term and the incidence of PIH was observed. Retrospectively, they were divided into two groups: Group I (those who did not develop PIH, n = 82) and Group II (those who developed PIH, n = 43). Blood pressure variability (BPV) parameters including baroreflex sensitivity (BRS), spectral heart rate variability (HRV), autonomic function tests (AFTs), inflammatory markers (interleukin-6, TNF-α, interferon-γ), and OS markers were measured in both the groups. Alterations in parasympathetic and sympathetic components of AFTs were analyzed. Link of various parameters to BRS was assessed by correlation and multiple regression analysis. Parasympathetic components of AFTs were decreased from the early part of pregnancy and sympathetic components were increased toward the later part of pregnancy. Decreased BRS, the marker of CV risk, was more prominent in Group II subjects. Independent contribution of interleukin-6 (ß = 0.276, P = 0.020), TNF-α (ß = 0.408, P = 0.002), interferon-γ (ß = 0.355, P = 0.008), and thiobarbituric-acid reactive substance (ß = 0.287, P = 0.015) to BRS was found to be significant. It was concluded that sympathetic overactivity that develops more in the later part (third trimester) of pregnancy contributes to SVI and genesis of PIH. In PIH women, CV risks are present from the beginning of pregnancy that intensifies in the later part of pregnancy. Retrograde inflammation and oxidative stress contribute to the decreased BRS in PIH.

Attenuated baroreflex sensitivity in normotensive prediabetes and diabetes in Indian adults.

PURPOSE/AIM OF THE STUDY: Though attenuated baroreflex sensitivity (BRS) is known to promote cardiovascular disease (CVD) risk in diabetics, its status in prediabetes has not been reported. Also, the link of BRS to CVD risk in normotensive diabetics has not been reported. This study aimed to evaluate the association of BRS to CVD risk in normotensive prediabetics and diabetics. MATERIALS AND METHODS: Participants (n = 154) of 18-45 years were divided into normoglycemics (n = 52), prediabetics (n = 64) and diabetics (n = 38) based on American Diabetes Association criteria. Body mass index, waist-hip ratio, waist-height ratio, body fat mass index, basal heart rate, systolic blood pressure, diastolic blood pressure, rate pressure product, BRS, heart rate variability (HRV), fasting plasma glucose, fasting insulin, lipid profile and atherogenic index of plasma (AIP) were measured. Indian Diabetes Risk Score (IDRS) and homeostatic model assessment of insulin resistance were calculated. RESULTS: There was significant increase in all the parameters except BRS, HRV and high-density lipoprotein in prediabetics and diabetics compared to normoglycemics. All these parameters were significantly altered in prediabetics compared to diabetics. Significant negative correlation was found between BRS and other parameters in prediabetics and diabetics. CONCLUSIONS: BRS was attenuated in normotensive prediabetics and diabetics with high IDRS, insulin resistance, AIP, dyslipidemia and reduced HRV that predisposes them to CVD risk. The study demonstrates CVD risk quite early in the prediabetics with reduced HRV, high body fat, hyperinsulinemia, insulin resistance, AIP and rate pressure product.

Prehypertension status, cardiometabolic risks, and decreased baroreflex sensitivity are linked to sympathovagal imbalance in salt-preferring individuals.

Salt preference has been reported to cause sympathovagal imbalance (SVI) and prehypertension. We investigated the role of inflammation, insulin resistance (IR), hyperlipidemia, and oxidative stress (OS) in genesis of SVI and cardiovascular (CV) risks in salt-preferring prehypertensives. The subjects were divided into no-salt-preferring (NSP, n = 87) and salt-preferring (SP, n = 89) group based on their preference for salted food. Body mass index (BMI), blood pressure (BP) variability parameters including baroreflex sensitivity (BRS), heart rate variability (HRV) indices, autonomic function tests, IR, lipid risk factors, inflammatory and OS markers, and renin were measured in both the groups. Based on the contribution of various cardiometabolic risks to low-frequency-high-frequency (LF-HF) ratio of HRV, the marker of SVI was assessed by multiple-regression analysis. Prediction of prehypertension status by the LF-HF ratio was assessed by bivariate logistic regression. BMI, heart rate, BP parameters, cardiac output, total peripheral resistance, LF-HF ratio, IR, atherogenic index, inflammatory, and OS markers were significantly increased, and BRS was significantly decreased in the SP group compared with the NSP group. There was an independent association of IR, atherogenic index, markers of inflammation and OS, and BRS with the LF-HF ratio in SP subjects, and the LF-HF ratio had significant prediction of prehypertension status in these subjects. It was concluded that IR, low-grade inflammation, atherogenic lipid profile, and OS contribute to SVI in SP subjects. Decreased BRS (the marker of CV risk) is linked to SVI, and SVI predicts prehypertension status in SP subjects.

Association of sympathovagal imbalance with cardiovascular risks in patients with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is associated with cardiovascular risks like obesity, insulin resistance, dyslipidemia that can lead to sympathovagal imbalance (SVI). The study was designed to assess the cardiovascular risk in PCOS and link of metabolic derangements to SVI. Thirty-five newly diagnosed PCOS patients and 32 age-matched controls were recruited. Waist-hip ratio, body mass index (BMI), basal cardiovascular parameters such as basal heart rate (BHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and rate pressure product (RPP) were recorded. Autonomic functions were assessed using short-term heart rate variability (HRV) analysis, heart rate and blood pressure response to standing (30:15 ratio), deep breathing (E:I ratio) and isometric handgrip (ΔDBPihg). Fasting plasma glucose, insulin, lipid profile and testosterone were assayed. Insulin resistance (HOMA-IR) and lipid risk factors were calculated. The cases had increased BHR, BMI, SBP, DBP, MAP and RPP. The ratio of low-frequency to high-frequency (LF-HF) of HRV, the marker of SVI was significantly increased in cases. 30:15 ratio and ΔDBPihg were increased and E:I ratio was decreased in the cases. HOMA-IR, lipid risk factors and testosterone were significantly elevated in cases. There was a significant correlation of LF-HF with BMI, BHR, RPP, insulin resistance and lipid risk factors. On regression analysis, insulin resistance and lipid risk factors had independent association with LF-HF. PCOS patients have SVI, decreased HRV and increased RPP and the potential cardiovascular risks. The insulin resistance and dyslipidemia contribute to SVI and cardiovascular risks in PCOS patients.

Assessment of cardiovascular autonomic function in patients with polycystic ovary syndrome.

AIM: The study was conducted to assess the sympathovagal balance in patients with polycystic ovary syndrome (PCOS) using short-term heart rate variability (HRV) analysis and conventional autonomic function tests (CAFT). METHODS: Thirty-one newly diagnosed patients with PCOS and 30 age-matched controls were recruited. Body mass index (BMI), waist : hip ratio (WHR), cardiovascular parameters such as basal heart rate (BHR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and rate-pressure product (RPP), and fasting blood glucose (FBG) were measured in both groups. Cardiovascular autonomic functions assessed were spectral analysis of HRV, heart rate and blood pressure response to standing (30:15 ratio), deep breathing (E:I ratio) and isometric handgrip (ΔDBP(ihg)). RESULTS: The cases had significantly increased BMI, WHR, BHR, SBP, DBP and RPP. Ratio of low-frequency to high-frequency power of HRV (LF-HF ratio), the marker of sympathovagal balance was significantly increased in cases compared to controls. Time-domain indices of HRV and E:I ratio were decreased, and 30:15 ratio, ΔDBP(ihg) and FBG were increased in cases. Though there was a significant correlation of LF-HF ratio with BMI, WHR, BHR, RPP and FBG, only BHR and RPP had independent contribution to LF-HF ratio. CONCLUSION: We conclude that PCOS patients have altered autonomic modulation in the form of increased sympathetic and decreased parasympathetic reactivity and HRV. The sympathovagal imbalance exposes them to cardiovascular morbidities.

Influence of sleep disturbance, depression, anxiety, and stress on quality of life in people with epilepsy.

OBJECTIVES: We assessed the quality of life, sleep, depression, anxiety, and stress in people with pharmacoresistant epilepsy (PRE) and newly diagnosed epilepsy (NDE). We also assessed the influence of sleep, depression, anxiety, and stress on the quality of life (QOL) and the complex association between these factors. METHODS: We recruited 80 PRE and 70 NDE people attending the epilepsy clinic. We assessed QOL, sleep quality, daytime sleepiness, and mood using the quality of life in epilepsy-31 inventory (QOLIE-31), Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS), and depression anxiety stress scale (DASS-21). We compared the results between the two groups of epilepsy populations. We performed univariate and multivariate linear regression to determine the factors affecting the QOLIE-31 total score. We applied Spearman's rank correlation to find the interrelationship between variables influencing QOL. RESULTS: We found significantly lower QOLIE-31 total scores (p = .001) in PRE compared to NDE. The PSQI and ESS did not differ significantly between the PRE and NDE groups. Anxiety (p = .002) and stress (p = .003) scores were significantly higher in PRE than in NDE. QOLIE-31 total scores showed a negative correlation with PSQI as well as symptoms of depression, anxiety, and stress scores in both groups. Multiple linear regression analysis revealed depression as a major factor influencing the QOLIE-31 total score in PRE (p = .001) and NDE (p = .003). We found significant complex associations between PSQI, depression, anxiety, stress, and QOLIE total scores in both groups. SIGNIFICANCE: The QOL is poorer for people with PRE than for those with NDE. Depression is a major determinant of QOL in PWE. These factors need to be considered to improve the QOL in epilepsy.

Assessment of Radiation Induced Pneumonitis and Pericarditis in Patients Undergoing Breast Conservative Treatment Using Hypofractionated Simultaneous Integrated Boost Technique.

INTRODUCTION: To determine the proportion of radiationinduced pneumonitis and pericarditis in patients who have received Hypo-fractionated Radiation along with simultaneous integrated boost technique after breast conservative surgery using a prospective observational study from a tertiary hospital. MATERIALS & METHODS: The incidence of radiationinduced pneumonitis and pericarditis was evaluated in all adult patients with biopsy-proven early-stage unilateral breast cancer who underwent breast-conserving surgery followed by hypo-fractionated radiation with a simultaneous integrated boost technique. Baseline assessments including a six-minute walk test, highresolution computed tomography (HRCT), pulmonary function tests (PFTs), electrocardiography (ECG) and echocardiography (ECHO) were performed. At three months post-radiation treatment, patients underwent follow-up assessments with a six-minute walk test, ECG and ECHO. At six months post-radiation treatment, patients underwent further assessments with a six-minute walk test, ECG, ECHO, PFTs, and HRCT of the thorax. Data analysis was performed using SPSS version 19. RESULTS: Our study investigated the incidence of acute radiation-induced pneumonitis and pericarditis in patients treated with hypofractionated VMAT-SIB technique in 20 eligible early breast cancer patients. The study found that the technique is feasible and achieves encouraging dosimetric parameters, including well achieved ipsilateral lung and heart doses. The reduced treatment time of 3-4 weeks compared to the previous 6-7 weeks with sequential boost was also found to be desirable in resource-constrained settings. The incidence of acute radiation pneumonitis and pericarditis was acceptable and comparable to existing data, with 90% of patients experiencing grade 1 radiation pneumonitis according to CTCAE v5.0. Post-treatment pulmonary function tests showed significant changes, particularly in patients who had received neoadjuvant chemotherapy and nodal irradiation. The six-minute walk test and Borg scale also showed a significant positive correlation with pulmonary function tests. There was no significant pericarditis during the follow-up. The study proposes that the hypofractionated radiotherapy using VMAT-SIB is a suitable alternative to conventional fractionation, with acceptable acute toxicities, but longer follow-up is required to assess the impact on late toxicities. CONCLUSION: Our research has shown that hypofractionated adjuvant radiotherapy with SIB is a safe and feasible treatment for patients with early breast cancer. This treatment method doesn't pose any significant short-term risks to the lungs or heart, and the SIB technique provides better coverage, conformity and sparing of organs at risk. Additionally, patients have reported positive cosmetic outcomes with this treatment. However, to make more accurate conclusions, we need to conduct further studies with larger sample sizes and longer follow-up periods to evaluate the potential longterm side effects of this treatment using VMAT in whole breast radiation.

Body mass index contributes to sympathovagal imbalance in prehypertensives.

BACKGROUND: The present study was conducted to assess the nature of sympathovagal imbalance (SVI) in prehypertensives by short-term analysis of heart rate variability (HRV) to understand the alteration in autonomic modulation and the contribution of BMI to SVI in the genesis of prehypertension. METHODS: Body mass index (BMI), basal heart rate (BHR), blood pressure (BP), rate pressure product (RPP) and HRV indices such as total power (TP), low-frequency power (LF), normalized LF (LFnu), high-frequency power (HF), normalized HF (HFnu), LF-HF ratio, mean heart rate (mean RR), square root of the mean squared differences of successive normal to normal intervals (RMSSD), standard deviation of normal to normal RR interval (SDNN), the number of interval differences of successive NN intervals greater than 50 ms (NN50) and the proportion derived by dividing NN50 by the total number of NN intervals (pNN50) were assessed in three groups of subjects: normotensives having normal BMI (Group 1), prehypertensives having normal BMI (Group 2) and prehypertensives having higher BMI (Group 3). SVI was assessed from LF-HF ratio and correlated with BMI, BHR, BP and RPP in all the groups by Pearson correlation. The contribution of BMI to SVI was assessed by multiple regression analysis. RESULTS: LF and LFnu were significantly increased and HF and HFnu were significantly decreased in prehypertensive subjects in comparison to normotensive subjects and the magnitude of these changes was more prominent in subjects with higher BMI compared to that of normal BMI. LF-HF ratio, the sensitive indicator of sympathovagal balance had significant correlation with BMI (P=0.000) and diastolic blood pressure (DBP) (P=0.002) in prehypertensives. BMI was found to be an independent contributing factor to SVI (P=0.001) in prehypertensives. CONCLUSIONS: It was concluded that autonomic imbalance in prehypertensives manifested in the form of increased sympathetic activity and vagal inhibition. In prehypertensives with higher BMI, vagal withdrawal was predominant than sympathetic overactivity. Magnitude of SVI (alteration in LF-HF ratio) was linked to changes in BMI and DBP. BMI had an independent influence on LF-HF ratio. It was advised that life-style modifications such as yoga and exercise would enable achieve the sympathovagal balance and blood pressure homeostasis in prehypertensives.

Effect of gender on sympathovagal imbalance in prehypertensives.

Although recently the incidence of prehypertension has increased considerably, the pathophysiological mechanisms and the effects of gender in its causation have not yet been fully elucidated. Therefore, in this study body mass index (BMI), waist-hip ratio (WHR), basal heart rate (BHR), blood pressure (BP), rate pressure product (RPP), and spectral indices of heart rate variability (HRV) were reordered and analyzed in normotensive and prehypertensive males and females. It was observed that low frequency-high frequency (LF-HF) ratio, the sensitive indicator of sympathovagal imbalance (SVI), is significantly more (P < .001) in male prehypertensives compared with female prehypertensives. Although SVI in prehypertensives was found to be due to both sympathetic activation and vagal inhibition, contribution of vagal withdrawal was prominent in males. The LF-HF ratio was significantly correlated with BMI, WHR, BHR, BP, and RPP, which was more prominent in male prehypertensives and the degree of correlation was more for WHR and diastolic pressure. It was concluded that vagal inhibition plays an important role in critical alteration of SVI in the genesis of prehypertension, especially in males, and WHR could be a better indicator of SVI in prehypertensives. It was suggested that prehypertensives should improve their vagal tone to restore the sympathovagal homeostasis.

Role of ventromedial hypothalamus on energy homeostasis in albino rats: effect of gender.

Various brain areas like the ventromedial hypothalamus (VMH) are known to influence food intake and body weight. Though obesity is more common in females, the reports on gender difference in the neural regulation of energy homeostasis are not adequate. Therefore, the present study was conducted to assess the gender difference in the effect of VMH lesion on food intake (FI), body weight (BW), serum lipid profile, thyroid profile, glucose and insulin levels and glucose-insulin ratio (GIR) in Wistar albino rats. Twenty-four Wistar albino rats were divided equally into control and experimental groups with 6 male and 6 female rats in each. In the experimental group, bilateral electrolytic lesion of VMH was performed by stereotaxy and post-lesion parameters were recorded. In the control group, VMH sham lesion was made. Male-female difference in each parameter was determined. Following VMH lesion, FI was increased (females, P < 0.01) and BW (males, P < 0.05) and GIR decreased in males (P < 0.001), which was significantly correlated with BW. T3 was more significantly correlated with FI and BW in females (P < 0.000 and P < 0.001). Following VMH lesion, male rats exhibited significant weight gain in the absence of proportionate hyperphagia indicating that weight-gain was mainly metabolic in nature. Also, the male rats developed more susceptibility to insulin resistance. The female rats developed resistance to weight-gain inspite of hyperphagia, which could be due to the higher T3 level.

Effect of lesion of nucleus septal medialis on energy homeostasis in Wistar rats.

Mesolimbic areas such as nucleus accumbens, amygdala and septal nuclei are known to influence food intake and body weight. However, the reports on gender difference in the neural regulation of obesity and energy homeostasis are incomplete. Therefore, the present study was conducted to assess the effect of lesions of nucleus septal medialis (NSM) and the gender difference of lesion on food intake (FI), body weight (BW), serum lipid profile, thyroid profile, glucose and insulin levels and glucose-insulin ratio (GIR) in Wistar albino rats. Twenty-four rats were divided equally into control and experimental groups having 6 male and 6 female rats in each group. In the experimental group, bilateral electrolytic lesion of NSM was performed by stereotaxy and post-lesion parameters were recorded. In the control group, sham-lesions of NSM were produced. Following lesion, blood glucose and serum insulin levels were decreased and GIR was increased significantly in female rats, but not in male rats. It was concluded that NSM is involved in energy homeostasis, especially in female rats.

Assessment of sympathovagal imbalance by spectral analysis of heart rate variability in prehypertensive and hypertensive patients in Indian population.

Though the incidence of hypertension has increased considerably in recent years, the pathophysiologic mechanism that causes progression from stage of prehypertension to hypertension has not been fully elucidated. Therefore, the present study was conducted to assess the sympathovagal imbalance in prehypertensives and hypertensives by spectral analysis of heart rate variability (HRV) to understand the nature of change in autonomic balance in this common dysfunction of mankind. Body mass index (BMI), basal heart rate (BHR), blood pressure (BP), and spectral indices of HRV such as total power (TP), normalized low frequency power (LFnu), normalized high frequency power (HFnu), ratio of low frequency power to high frequency power (LF-HF ratio), mean heart rate (mean RR), square root of the mean squared differences of successive normal to normal intervals (RMSSD), the number of interval differences of successive NN intervals greater than 50 ms (NN50), and the proportion derived by dividing NN50 by the total number of NN intervals (pNN50) were assessed in three groups of subjects: normotensives (n = 32), prehypertensives (n = 28), and hypertensives (n = 31). Sympathovagal balance was analyzed and correlated with BMI, BHR, and BP in all the groups. It was observed that autonomic imbalance in prehypertensives was due to proportionate increased sympathetic activity and vagal inhibition, whereas in hypertensives, vagal withdrawal was more prominent than sympathetic overactivity. The LF-HF ratio, the sensitive indicator of sympathovagal balance, was significantly correlated with BMI, BHR, and BP. It was concluded that vagal inhibition plays an important role in the critical alteration of sympathovagal balance in the development of clinical hypertension in prehypertensive subjects.

Association of albumin-globulin ratio with sympathovagal imbalance in pregnancy-induced hypertension.

The early prediction of pregnancy-induced hypertension (PIH) is based on the demonstration of increased sympathetic activity in early part of pregnancy. However, the mechanisms that increase sympathetic activity in PIH have not yet been fully elucidated. Therefore, in the present study we have investigated the link of albumin-globulin ratio (AGR) to sympathovagal imbalance in PIH patients. Spectral analysis of HRV was performed in three groups of subjects (Group I: normal pregnant women; Group II: pregnant women with risk factors for PIH, but did not develop PIH; Group III: pregnant women with risk factors and developed PIH) and their biochemical parameters including AGR were recorded. It was observed that LF-HF ratio, the most sensitive indicator of sympathovagal balance was significantly high (P < 0.01) since early pregnancy in group III compared to other groups, which was considerably correlated with AGR in group III (PIH subjects). It was suggested that alteration in AGR could have direct contribution to the sympathovagal imbalance that plays a critical role in the genesis of PIH.

Study of sympathovagal imbalance by spectral analysis of heart rate variability in young prehypertensives.

Though prehypertension has recently been considered as a risk factor for cardiovascular accidents, the pathophysiological mechanism that causes the development of prehypertension in normotensive subjects has not been fully elucidated. Therefore, the present study was conducted to assess the sympathovagal imbalance in prehypertensives and normotensives by spectral analysis of heart rate variability (HRV) to understand the nature of change in autonomic balance in this dysfunction. Body mass index (BMI), waist-hip ratio (WHR), basal heart rate (BHR), blood pressure (BP), rate-pressure product (RPP) and spectral indices of HRV such as total power (TP), normalized low frequency power (LFnu), normalized high frequency power (HFnu), ratio of low frequency power to high frequency power (LF-HF ratio), mean heart rate (mean RR), square root of the mean squared differences of successive normal to normal intervals; (RMSSD), the number of interval differences of successive NN intervals greater than 50 ms (NN50) and the proportion derived by dividing NN50 by the total number of NN intervals (pNN50) were assessed in two groups of young subjects: normotensives (n=68) and prehypertensives (n=66). Sympathovagal balance (SVB) was analyzed and correlated with BMI, WHR, BHR, BP and RPP in both the groups. It was observed that autonomic imbalance in prehypertensives was due to increase in both sympathetic activity and vagal inhibition. LF-HF ratio, the sensitive indicator of SVB was significantly correlated with BMI, WHR, BHR, BP and RPP in prehypertensive subjects. It was concluded that vagal inhibition might be important in the critical alteration of sympathovagal balance in the development of prehypertension in young normotensive subjects.

Role of Ventromedial Hypothalamus in Sucrose-Induced Obesity on Metabolic Parameters.

BACKGROUND: Obesity is because of excessive fat accumulation that affects health adversely in the form of various diseases such as diabetes, hypertension, cardiovascular diseases, and many other disorders. Our Indian diet is rich in carbohydrates, and hence the sucrose-induced obesity is an apt model to mimic this. Ventromedial hypothalamus (VMH) is linked to the regulation of food intake in animals as well as humans. PURPOSE: To understand the role of VMHin sucrose-induced obesity on metabolic parameters. METHODS: A total of 24 adult rats were made obese by feeding them on a 32% sucrose solution for 10 weeks. The VMH nucleus was ablated in the experimental group and sham lesions were made in the control group. Food intake, body weight, and biochemical parameters were compared before and after the lesion. RESULTS: Male rats had a significant weight gain along with hyperphagia, whereas female rats did not have a significant weight gain inspite of hyperphagia. Insulin resistance and dyslipidemia were seen in both the experimental and control groups. CONCLUSION: A sucrose diet produces obesity which is similar to the metabolic syndrome with insulin resistance and dyslipidemia, and a VMH lesion further exaggerates it. Males are more prone to this exaggeration.