Potential Association of Triglyceride Glucose Index with Cardiac Autonomic Neuropathy in Type 2 Diabetes Mellitus Patients

Cardiac autonomic neuropathy (CAN) is a common and most neglected complication of diabetes, estimated to be roughly 8% in recently diagnosed patients and greater than 50% in patients with chronic disease history. The insulin resistance (IR) itself is bidirectionally associated with increased risk of type 2 diabetes mellitus (T2DM) and CAN is a predisposing factor. The primary objective of the present study was aimed to find a correlation of triglyceride glucose index (TyG index) in CAN patients along with the prevalence of CAN in T2DM patients as a secondary objective. This prevalence study was conducted on 202 patients visiting the diabetic clinic of Hamdard Institute of Medical Sciences and Research, Jamia Hamdard (HIMSR) teaching hospital in New Delhi, India who fulfilled the inclusion criteria. The Ewings autonomic function test was used for diagnosis of CAN. TyG index was calculated for patients based on fasting levels of glucose and triglyceride. The CAN was diagnosed in 62 participants out of 202 T2DM patients (overall prevalence 30.7%). The mean ± standard deviation (SD) for TyG index was 10.3 ± 0.2 and 9.5 ± 0.2 in CAN positive, T2DM patients, respectively. The difference of TyG index, in CAN positive and T2DM patients, was highly significant (P < 0.001). Further correlation analysis was performed to find an association of TyG index, duration, and age with patient groups. TyG index showed a positive correlation with heart rate during deep breathing (HRD), heart rate variation during standing (HRS), blood pressure (BP) response to handgrip and BP response to standing. Our finding highlights the TyG index, low-cost IR index, might be useful as an alternative tool for the early screening of patients at a high risk of diabetic neuropathy.

Assessment of Cardiovascular Autonomic Functions and Baroreceptor Reactivity in Women with Premenstrual Syndrome.

Objectives: The study was conducted to assess the autonomic status of women with mild PMS using shortterm heart rate variability (HRV) analysis and conventional autonomic function tests (CAFT). Methods: Sixty females in the age group 17-25 years with mild premenstrual syndrome were identified using a self-report questionnaire, the shortened premenstrual assessment form. HRV and CAFTs were recorded 1- 5 days prior and 8-10 days after menstruation. Results: The subjects showed a significant increase in HR and SBP in luteal phase. In HRV, an increase in mean HR and LF-HF ratio were seen in the luteal phase whereas an increase in the NN50, RMSSD and pNN50, HF, HF(nu) and TP were seen in the follicular phase. In CAFT, no change in HRB, 30:15 and E/ I ratios but increase in ?DBP(ihg) in the luteal phase was seen. Conclusion: The increase in HR and SBP in the luteal phase could be because increased water and salt retention due to the ovarian steroids. A decrease in HRV, increase in ?DBPihg with no change in 30:15 ratio in the luteal phase could be attributed to delayed withdrawal of ovarian hormones in the luteal phase.

Cardiovascular autonomic functions & cerebral autoregulation in patients with orthostatic hypotension.

Background & objectives: Patients of orthostatic hypotension may or may not have symptoms of the cerebral hypoperfusion despite fall in the blood pressure. The present study was done to quantify autonomic functions and cerebral autoregulation in patients of orthostatic hypotension with or without symptoms. Methods: The study was conducted in 15 patients of orthostatic hypotension and 15 age, sex matched control subjects. The sympathetic reactivity was measured by diastolic blood pressure response to handgrip test (ΔDBP in HGT) and cold pressor test (ΔDBP in CPT). The parasympathetic reactivity was measured by E:I ratio during deep breathing test (DBT) and Valsalva ratio (VR) during Valsalva maneuver. The cerebral autoregulation was computed from the changes in the cerebral blood flow, cerebrovascular conductance and blood pressure measured during different time points during head-up tilt (HUT). Results: The sympathetic reactivity was lower in patients as compared to controls [ΔDBP in HGT: 10 (4 - 16) vs 18 (12 - 22) mmHg, P<0.01; ΔDBP in CPT : 10 (4-12) vs 16 (10-20) mmHg, P<0.01]. The parasympathetic reactivity was also lower in patients as compared to controls. The sympathetic and parasympathetic reactivity was comparable in the symptomatic and asymptomatic patients. The maximum fall in blood pressure during HUT was comparable between symptomatic and asymptomatic patients (29.14 ± 10.94 vs 29.50 ± 6.39 mmHg), however, the percentage fall in the cerebral blood flow was significantly higher in the symptomatic (P<0.05) compared to asymptomatics. Interpretation & conclusions: Patients with orthostatic hypotension had deficits in sympathetic and parasympathetic control of cardiovascular system. Cerebral autoregulation was present in asymptomatic patients (increase in cerebrovascular conductance) during HUT while it was lost in symptomatic patients.

Evaluation of Neurophysiological Parameters: Autonomic Status and Acute Pain Perception in Migraneurs.

Introduction: Painful conditions are associated with autonomic dysfunction and altered pain perception. However, data regarding autonomic status in migraineurs is not conclusive and there are few studies regarding acute pain perception in these cases. Aims: This study was conducted to assess various neurophysiological parameters namely autonomic functions using the autonomic function tests and acute pain perception using the cold pressor test in migraneurs. Material and methods: 60 migraineurs and 30 age and gender matched control subjects were included in this study after screening for the exclusion criteria and following a written consent. Diagnosis of migraine was made according to the International Classification of Headache Disorders(ICHD) – 2 Criteria. In the pain free state of the subjects, autonomic function tests including basal heart rate variability, E:I ratio, 30:15 ratio, postural challenge test and sustained handgrip test were carried out together with the cold pressor test. Unpaired t-test was used for analysing the data. Result: Migraineurs showed a trend towards increased parasympathetic tone, as compared to the control subjects, though the p-values were not significant. The pain threshold was lower while the pain tolerance was significantly lower in migraineurs as compared to controls (p= 0.00).Conclusion: In our study we observed an increased vagal tone together with lower values of pain threshold and pain tolerance in migraineurs, indicating that certain neurophysiological parameters are affected in painful conditions like migraine.

Effect of thyroxine therapy on autonomic status in hypothyroid patients.

The aim of the present study was to evaluate the impact of hypothyroidism on the autonomic regulation of the cardiovascular system by analyzing sympathetic and parasympathetic influences on the heart and the effect of thyroxine replacement. Thirty newly diagnosed female hypothyroid patients with mean age 32.73±9.98 years were recruited from the Thyroid Clinic, GTB Hospital, Delhi. Various Autonomic function tests to assess Basal heart rate variability, parasympathetic activity (E:I Ratio, 30:15 Ratio, Valsalva Ratio) and sympathetic activity (Postural Challenge test, Sustained handgrip test) were done before and after attainment of euthyroidism. There was significant increase in parasympathetic activity on achieving euthyroid state. The sympathetic activity too significantly improved after L-thyroxine supplementation. Lipid profile parameters significantly decreased after achieving euthyroid state. Our findings are consistent with previous reports that thyroxine therapy appears to restore the efferent vagal activity and alters the relative contribution of systems that maintain resting blood pressure and heart rate.

Successful Treatment of Panic Disorder with Ryukotsuto / 日本東洋医学雑誌

We encountered a patient with intractable panic disorder who responded extremely well to Ryukotsuto, a Kampo preparation. Beginning in March 2003, a 55-year-old female began to lose vigor and concentration, while developing palpitations and experiencing a rise in blood pressure (systolic pressure≥190mmHg) accompanied by sudden anxiety. When these symptoms became intense, she was brought to a hospital by ambulance. Although close examination revealed no abnormalities, on clinical diagnosis, however, autonomic imbalance was recognized. Despite treatment with antidepressants and minor tranquilizers, including selective serotonin reuptake inhibitors (SSRI), no improvement was observed. A series of medicinal Kampo preparations, prescribed one after another, also had no effect. For further treatment, she was referred to our hospital on July 22, 2005. At the first consultation, a diagnosis of panic disorder was made, according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Hon-Ton disease was suspected based on clinical findings, and Ryokeikansoto was prescribed as a decoction. However, no positive effects were observed after 1 week, while marked incompetence, forgetfulness, and depression were noted. Therefore, based on the results of a self-rating depression scale (SDS), a profile of mood states (POMS), and autonomic function tests, such as pupillary dynamics at the first consultation, panic disorder accompanied by extreme tension with depression was diagnosed. Consequently, her Kampo preparation was changed to Ryukotsuto. As a result, symptoms virtually disappeared and all western drugs were discontinued. Psychological tests, autonomic function tests, and her diagnostic scores for conditions of Ki, Ketsu, and Sui also improved. We conclude that Ryukotsuto may be an effective treatment for panic disorder accompanied by depression.

Correlation between Cardiac Autonomic Function Test and Subclinical Neuropathy in Type 1 Diabetic Children / 대한소아내분비학회지

PURPOSE:Autonomic neuropathy in adult diabetics is known to be common and poor in prognosis. Cardiac autonomic neuropathy increases sudden cardiac death and is present before apparant cardiac symptoms. Subclinical diabetic peripheral neuropathy is common with type 1 diabetes. In children, few studies for subclinical peripheral neuropathy and cardiac autonomic neuropathy were reported but the results were inconsistent. The authors investigated subclinical cardiac and peripheral neuropaties and evaluated correlation between nerve conduction velocity(NCV) and cardiac autonomic function(CAF) test in type 1 diabetic children and adolescents METHODS:Over 5 years from 1997 to 2002, 27 IDDM without clinical neuropathy were registered. Total 57 CAF and NCV were tested every 2 or 3 years. Duration of diabetes, average HbA1c during 1 year prior to the test, and urinary microalbumin excretion for 24 hours were assessed. Diabetic autonomic nervous function was evaluated by cardiovascular reflex test:falling systolic blood pressure in response to standing, heart rate changes in response to standing, beat-to-beat rate variation during deep breathing, RR interval change during and after Valsalva maneuver. Subclinical peripheral neuropathy was evaluated by NCV in both upper and lower extremities. Correlation of parameters according to NCV abnormality and microalbuminuria were analyzed. RESULTS:The age, duration of diabetes and microalbuminuria were not statistically different between children with normal and abnormal NCV. The level of HbA1c was associated with NCV abnormality. In a multivariate logistic model for NCV abnormality, level of HbA1c showed statistical significance after controlling the effects of age, duration of diabetes, and urinary microalbumin level, and the odd ratio was 1.532. The degree of CAF abnormality was marginally significant in the logistic model. Children with microalbuminuria showed older age and longer duration of diabetes than those without microalbuminuria. However, mean HbA1c level was not significantly different between the two groups. Degree of CAF abnormality was not significantly associated with microalbuminuria, either. In a general linear model including urinary albumin level as the dependent variable, none of independent variables was statistically significant. CONCLUSION: Therapy against neuropathy should be considered in patients with high HbA1c and abnormal CAF test even without clinically apparent neuropathy.

Autonomic Function Tests in Primary Hyperhidrosis

BACKGROUND: The cause of essential hyperhidrosis and its relationship to autonomic dysfunction are still uncertain. Autonomic function test in essential hyperhidrosis has been rarely studied and the results are variable. So we studied the systemic autonomic function test in patients with essential hyperhidrosis. METHODS: We studied twenty-five patients with hyperhidrosis and thirty-eight healthy age-matched controls from August 1999 to July 2000. The amount of hydra-tion was measured by semi-quantitative method. The autonomic function test consists of four items; sympathetic skin response, heart rate variation with respiration, valsalva ratio, blood pressure and heart rate variation with position. We also checked BDI (Beck Depressive Inventory) and STAI (State-Trait Anxiety Inventory) to evaluate the psychological factor affecting the hyperhidrosis. RESULTS: The amount of hydration was significantly increased in patients with essen-tial hyperhidrosis. The latency and amplitude of sympathetic skin response show no difference between two groups. There is no significant change in heart rate variation with respiration, valsalva ratio and blood pressure and heart rate variation with posture in essential hyperhidrosis patients. However, the mean STAI score of hyperhidrosis patients is higher compared to the normal population. CONCLUSIONS: The systemic autonomic function test of essential hyperhidro-sis patients shows no significant abnormality in our study, but emotional factors such as anxiety should be considered in essential hyperhidrosis. And more specialized studies should be designed to identify the systemic autonomic function in essential hyperhidrosis.

Sympathetic skin response and cardiovascular autonomic function tests in Parkinson's disease

Autonomic dysfunction commonly occurs in Parkinson's disease, but the pathogenesis of autonomic dysregulation remains uncertain. Autonomic functions regulating the cardiovascular system have been investigated in Parkinson's disease, but those involving the extremities has not been well demonstrated. To compare autonomic dysfunctions of the cardiovascular system with those of the extremities, we performed sympathetic skin response (SSR) and cardiovascular autonomic function tests (CAFT) - 30:15 ratio, E:I ratio, Valsalva ratio, isometric exercise test (IET) - in 37 patients with Parkinson's disease and 33 age- and sex-matched healthy controls. The patients were asked to stop antiparkinsonian medications for at least 12 hours prior to the tests. SSR was measured at the right hand and foot after electrical stimulation of the right median and posterior tibial nerves. Absent SSR at either one or both extremities and CAFT beyond normal ranges were regarded as abnormal. Abnormal SSR was observed in 59% of patients, while abnormal CAFT were found in the range of 32%-81%. Patients with abnormal SSR showed more frequent and severe CAFT abnormalities than did patients with normal SSR. Among the CAFT, IET was well correlated with the SSR. The results suggest that parkinsonian sympathetic dysfunction involving either the cardiovascular system or the extremities may have the same pathophysiology.