Nerve Function Status Research Articles

Neuropathic changes in young type 2 diabetes mellitus related to high serum t-PA

Background and Aims: A substantial number of diabetic patients, diagnosed at relatively younger age, who don’t fit to typical type 2 and type 1 class of diabetes. These patients usually present with very high level of glycemia. The uniqueness of this group of patient provide the opportunity to explore the pathophysiology of nerve functional status at an early stage of diabetes. The present study was aimed to determine markers of endothelial dysfunction and evaluate nerve functional status of a group of newly diagnosed clinically uncomplicated young diabetic patients. Material and Methods: A total number of 32 (male-13 and female-19) newly diagnosed young (diabetes diagnosed under 30 yrs) were consecutively recruited from BIRDEM Out-patient department and 30 age-, BMI-matched healthy subjects with no family history of diabetes up to second generation served as controls. Serum fructosamine was measured by reduction test with NBT method. Serum C-peptide, endothelin-1 and tissue plasminogen activator (t-PA) by ELISA and von Willebrand factor (vWF) by Radial Immunodiffusion (RID) methods. Urinary albumin measured by immunoturbidimetry method. Nerve functional status was evaluated by nerve conduction velocities (NCV), distal latencies (DL), compound muscle action potential (CAMP), F wave latencies (FWL), nerve action potential (SNAP) for motor and sensory nerve as appropriate following the standard protocol. Results: Severe hyperglycemia in the diabetic group was reflected in their mean (SD) fasting C-peptide and fructosamine level. Altered endothelial dysfunction, as evidenced by significantly high tissue plasminogen activator (t-PA) (p<0.001) in the diabetic group. Albumin creatinine ratio (ACR) was almost similar in the two groups. Ulnar distal latency was similar in both the groups. But its CAMP and NCV were significantly lower in the diabetic group (p<0.02-0.001). Ulnar F wave latency were significantly higher (p=0.016) in the diabetic group. Ulnar sensory conduction parameters did not show any difference between two groups. Peroneal motor and sural sensory functional status of the diabetic subjects showed similar trend like that of ulnar motor and sensory status. Peroneal nerve motor NCV was significantly negatively correlated with fasting glucose [r=- 0.456, p=0.001]. Peroneal motor distal latency was significantly correlated with fasting fructosamine [r=0.439, p=0.012]. Fasting fructosamine showed significant negative correlation with motor peroneal NCV [r=-0.572, p=0.001], motor ulnar NCV [r=-0.468, p=0.007], both ulnar and sural sensory NAP (p=0.02 for both]. On the basis of F wave latency 53% of diabetic subjects had diabetic neuropathy and markedly higher t-PA compared to nonneuropathy groups (p=0.001). Conclusions: The data suggest that (i) Young type 2 diabetic subjects had endothelial dysfunction at the time of diagnosis even in the presence of normoalbuminuria state; (ii) Motor nerve conduction parameters are affected more than the sensory component; (iii) F wave latencies are more frequently and early to be involved in these subjects and linked to high serum t-PA. DOI: http://dx.doi.org/10.3329/bjms.v13i2.18302 Bangladesh Journal of Medical Science Vol.13(2) 2014 p.190-197

Correlation to Serum Ionized Calcium and Magnesium Concentration with Sympathetic Nerve Functions in Type 2 Diabetes Mellitus

Background : In type 2 DM, a metabolic disorder causes disturbances of different metabolic processes of the body including electrolyte imbalance. Therefore changes in serum level of Ca2+ and Mg2+ may have some relationship to the occurrence of neuropathy. Objective : The study has been designed to observe the sympathetic nerve function status in type 2 diabetic subjects in order to assess the relationship between serum ionized calcium & magnesium. Study design : This cross section study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. Forty seven type 2 diabetic subjects were included in two groups. Group B consisted of 25 recently diagnosed diabetic subjects aged 40-68 years and group C consisted of 22 subjects having duration of diabetes for 10-20 years. Twenty five (25) age and BMI matched healthy subjects were included in group A (non-diabetic) for control. Methods : Sympathetic nerve function were assessed by two simple non-invasive cardiovascular reflex tests. These were systolic blood pressure, response to lying to standing up and diastolic blood pressure response to distain hand grip test. Ionized serum calcium and magnesium were measured by ion sensitive electrode method using NOVA electrode. Data were analyzed by ‘t’ test, Pearson’s correlation co-efficient. Results: Serum ionized calcium levels were significantly higher in both the diabetic group B (P<0.001) and C (P<0.001) than that of control group A. Serum ionized magnesium level was significantly higher in diabetic group C (P<0.001) compared to that of control group A. Pearson’s correlation of ionized calcium and magnesium with sympathetic nerve function parameters were done. Statistically significant relation was found in group B between sustained hand grip test with ionized calcium and in group C between systolic blood pressure response to standing with ionized magnesium. Conclusion : Serum ionized calcium & magnesium level was increased in type 2 diabetic patients irrespective of duration and some correlation was found with sympathetic nerve function parameters DOI: http://dx.doi.org/10.3329/updcj.v3i2.17991 Update Dent. Coll. j: 2013; 3 (2): 03-08

Parasympathetic Nerve Function Status in Female with Rheumatoid Arthritis

Background: Sudden cardiac death in patients with Rheumatoid Arthritis has been attributed to the decreased vagal drive to the heart. Objective: To assess cardiac parasympathetic nerve function status in patients with Rheumatoid Arthritis (RA). Methods: This cross sectional study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka from January to December 2010. Sixty female RA patients aged 18-50 years were included in the study group. They were enrolled from the Out Patient Department of Rheumatology Wing of the Department of Medicine, BSMMU, Dhaka. For comparison age matched thirty apparently healthy females were also studied as control. To assess parasympathetic nerve function status, all the subjects were examined by three noninvasive cardiovascular reflex tests such as heart rate response to valsalva maneuver (valsalva ratio), heart rate response to deep breathing and heart rate response to standing (30th :15th ratio). For statistical analysis independent sample t test was used. Results: Mean values of valsalva ratio, deep breathing test and 30th :15th ratio were significantly (p<0.001) lower in rheumatoid arthritis patients compared to those of healthy control. Conclusion: From this study it may be concluded that lower cardiac parasympathetic nerve activity characterized the autonomic nerve dysfunction in patients with Rheumatoid Arthritis. DOI: http://dx.doi.org/10.3329/jbsp.v8i1.16643 J Bangladesh Soc Physiol. 2013, June; 8(1): 21-25

Ovarian Hormones During Different Phases of Ovarian Cycle In Healthy Young Women

Background: Women having regular ovarian cycle often experience premenstrual syndrome which may be associated with alterations of autonomic nerve function due to fluctuation of ovarian hormones during different phases of ovarian cycle. Objective: To observe the parasympathetic nerve function status and their relationships with ovarian hormones during different phases of ovarian cycle in healthy young women. Methods: This cross sectional study was carried out in the department of Physiology at BSMMU, Dhaka in 2007 on 30 eumenorrhogic healthy females aged 20 to 30 years. Serum estrogen and progesterone were measured by MEIA method and parasympathetic nerve functions were assessed by valsalva, deep breathing test and orthostatic test during follicular and luteal phases of ovarian cycle. Data were analyzed by paired student ‘t’ test, and Pearson’s Correlation coefficient test where applicable. Results: Mean resting HR,SBP,DBP and all measures of parasympathetic nerve function were similar in all phases of ovarian cycle. With serum estrogen level, deep breathing showed significant (p<0.05) positive correlation in follicular and luteal phase and valsalva showed significant positive correlation during luteal phase. Conclusion: The results this study suggest that estrogen has got positive influence on parasympathetic nerve function which support cardioprotective role of estrogen in premenopausal females. DOI: http://dx.doi.org/10.3329/jbsp.v7i2.14456 J Bangladesh Soc Physiol. 2012, December; 7(2): 83-88

Heart Rate Variability in Patients with Rheumatoid Arthritis

Background: Altered cardiovascular autonomic nerve function with impaired sympathovagal balance is found in rheumatoid arthritis (RA). Heart Rate Variability (HRV) analysis is an important tool for assessment of autonomic nerve activity. Objective: To assess cardiac autonomic nerve function status in patients with Rheumatoid arthritis (RA) by time domain measures of HRV. Methods: This cross sectional study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka from January to December 2010. Sixty female RA patients, age range 18-50 years were constituted study group enrolled from the Out- patient Rheumatology Wing, Department of Medicine, BSMMU. Age matched thirty apparently healthy females were studied as control. Time domain measures of Heart Rate Variability (HRV) such as Mean RR intervals, Mean HR, SDNN, RMSSD, NN50% and PNN 50% were recorded for 5 minutes by a Polygraph machine to observe cardiac autonomic nerve function activity. Data were analyzed by independent sample t test. Results: Mean R-R interval, SDNN, RMSSD, PNN50%, NN50% were significantly lower (p<0.001) but heart rate was significantly (P<0.001) higher in rheumatoid arthritis patients. Conclusion: Cardiac autonomic nerve function is impaired and characterized by reduced resting parasympathetic activity in female Rheumatoid Arthritis patients. DOI: http://dx.doi.org/10.3329/jbsp.v7i2.14455 J Bangladesh Soc Physiol. 2012, December; 7(2): 78-82

Analysis of pain and functional status of patients with knee osteoarthritis after transcutaneous electrical nerve stimulation treatment

Objective. Evaluation of analgesic effect of transcutaneous electrical nerve stimulation (TENS) and functional status of patients with knee osteoarthritis in three intervals: immediately after treatment, one and three months after therapy. Methods. Sample consisted of 40 patients suffering from knee osteoarthritis, aged from 50-75 years. In examinees' evaluation, the same protocol was used for all patients: circumference of knees across the middle of patella, perimeter of knee movements, and rough muscle strength of quadriceps femoris muscle. Measurements were performed before and after therapy, after a month, and after three months. The questionnaire of pain, short form of McGill pain questionnaire, was filled in the same time interval. TENS procedures were applied five times of week, total of ten days. The same protocol of kinesitherapy treatment applied to all patients, uniformly. In statistical analysis we used descriptive methods and t-test. Results. There was an improvement of functional state concerning the decrease of circumference of knees, increase of perimeter of knee movement as well as an increase of rough muscle strength, with the greatest effect after three months (after the end of therapy). The greatest analgesic effect was after a month of applied treatment protocol. Conclusion. Application of transcutaneous electrical nerve stimulation, as simple and non-invasive procedures in treatment patients with knee osteoarthritis together with continuous application of kinesitherapy, improve the functional status as well as the better quality of life of the patient.

Effects of intracavernous injection of adipose-derived stem cells on cavernous nerve regeneration in a rat model.

The aim of this study was to investigate effects of intracavernous injection of adipose-derived stem cells (ADSCs) on cavernous nerve (CN) regeneration and functional status in a nerve-crush rat model. Thirty Sprague-Dawley male rats were randomly divided into three equal groups: one group underwent sham operation, while two groups underwent bilateral CN crush. Crush-injury group was treated at the time of injury with intracavernous injection of ADSCs, or injured control group with no further intervention. Erectile function was assessed by CN electrostimulation after 3 months. Penile tissue and crushed nerves were collected for histology. Three months after surgery, in the group that underwent bilateral nerve crushing with no further intervention, the functional evaluation showed a lower mean maximal intracavernous pressure (ICP) and maximal ICP per mean arterial pressure (MAP) with CN stimulation than those in the sham group. In the group with an immediate intracavernous injection of ADSCs, the mean maximal ICP and maximal ICP/MAP were significantly higher than those in the injured control group. Histologically, the group with the intracavernous injection of ADSCs had more myelinated axons of CNs and more NADPH-diaphorase-positive nerve fibers than the injured control group but fewer than the sham group. Intracavernous injection of ADSCs treatment had beneficial effects on the smooth muscle/collagen ratio in the corpus cavernosum. These results show that the intracavernous injection of ADSCs to the site of CN-crush injury facilitates nerve regeneration and recovery of erectile function. Our research indicates that penile injection of ADSCs can improve recovery of erectile function in a rat model of neurogenic ED.

Power Spectral Analysis of Heart Rate Variability in Female Rheumatoid Arthritis Patients

Background: Association of increased cardiovascular morbidity and higher sympathetic activity in patients with Rheumatoid arthritis (RA) has been recognized. Heart rate variability (HRV) is a useful measure to assess sympatho-vagal balance.Objective: To assess autonomic nerve function status in patients with Rheumatoid Arthritis (RA) by HRV analysis.Methods: This cross sectional study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka from January to December 2010. Sixty female RA patients aged 18-50 years were included in the study group. They were enrolled from the Out Patient Department of Rheumatology Wing of the Department of Medicine, BSMMU, Dhaka. For comparison age matched thirty apparently healthy females were also studied as control. The HRV parameters were recorded by a Polyrite machine. For statistical analysis independent sample t test was used.Results: Mean resting pulse rate, diastolic blood pressure and mean systolic blood pressure were higher in rheumatoid arthritis patients in comparison to those of healthy control. Mean values of LF power, LF norm and LF/ HF were significantly higher (p<0.001) & TP and HF power, HF norm were significantly lower (p<0.001) in RA patients in comparison to those of healthy control.Conclusion: This study may conclude that sympathetic activity was higher with lower parasympathetic activity along with shifting of sympathovagal balance towards sympathetic predominance in patients with rheumatoid arthritis. DOI: http://dx.doi.org/10.3329/jbsp.v7i1.11153 J Bangladesh Soc Physiol. 2012, June; 7(1): 8-12

Surgical management of petroclival meningiomas invading into cavernous sinus

To analyze the clinical features, surgical strategy and management outcomes of petroclival meningioma invading into cavernous sinus. Fifteen cases with petroclival meningioma invading into cavernous sinus were retrospectively analyzed. The presigmoidal approach was selected to remove tumors. The surgical strategy for tumor in cavernous sinus was partial resection combined with radiosurgery. Postoperative cranial nerve function and patient survival status were analyzed. The main symptoms of subtype of petroclival meningiomas were headache, abducens nerve palsy and trigeminal neuropathy. Gross total tumor removal was achieved in 13 cases and more than 90% resection in 2 cases. There was no operative death. Nine cases suffered from new postoperative cranial nerve deficits. After a follow-up of 6 - 59 months, complete improvement was achieved in oculomotor nerve deficits, much improvement in VII nerve deficit, but V and VI nerve function deficits improved slightly. The tumor progression-free survival rate was 86.7%. Rational surgical strategy to petroclival meningiomas invading into cavernous sinus should be suggested to reduce the operative morbidity and improve the survival quality of these patients.

The effect of platelet-rich plasma on cavernous nerve regeneration in a rat model

The aim of this study was to investigate the effect of platelet-rich plasma (PRP) on cavernous nerve (CN) regeneration and functional status in a nerve-crush rat model. Twenty-four Sprague-Dawley male rats were randomly divided into three equal groups: eight had a sham operation, eight underwent bilateral nerve crushing with no further intervention and eight underwent bilateral nerve crushing with an immediate application of PRP on the site of injury. Erectile function was assessed by CN electrostimulation at 3 months and nerve regeneration was assessed by toluidine blue staining of CN and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining of penile tissue. Three months after surgery, in the group that underwent bilateral nerve crushing with no further intervention, the functional evaluation showed a lower mean maximal intracavernous pressure (ICP) and maximal ICP per mean arterial pressure (MAP) with CN stimulation than those in the sham group. In the group with an immediate application of PRP, the mean maximal ICP and maximal ICP/MAP were significantly higher than those in the injured control group. Histologically, the group with the application of PRP had more myelinated axons of CNs and more NADPH-diaphorase-positive nerve fibres than the injured control group but fewer than the sham group. These results show that the application of PRP to the site of CN-crush injury facilitates nerve regeneration and recovery of erectile function. Our research indicates that clinical application of PRP has potential repairing effect on CN and peripheral nerves.

Sympathetic Nerve Function Status in Type 2 Diabetes Mellitus: Relationship with Glycaemic Status and Duration

The study was designed to observe the sympathetic nerve fiarction status in recently diagno.ved and long duration (10-20 years) type 2 diabetic subjects in order to assess whether the duration of diabetes has any influence on the sympathetic nerve firoudion. The present SlUdy was carried on also to obtain a base line dam in the form of a set of normal reference willies of cardiovascular reflex rest parameters in a selected group of adult Bangladeshi population. For this purpose 47 type 2 diabetic subjects were included in ors groups, group A consisted 1,1. 25 recently diagnosed diabetic subjects and group B consisted of 22 subjects having duration of diabetes for 10.20 years. Bventy five age and BAB nratched healthy subjects were included in group C (non-diabetic) for control and also to observe the baseline data. Sympathetic nerve fraction was a.vseused by two simple nominversive cardiovascular reflex teals. Tests item .orstained handgrip tests and blood pressure response to standing. The normal or reference values obtained from the norm-diabetic subjects of the present study were compared to those in) published reference values of different poptelatiorr around the world and no apparent differences trvre observed. Glycaemic vanes of the diabetic subjects were more or less controlled. Cardiovascular reflex test for sympathetic function were finind no be significantly a:throat in long duralion diabetic group in comparison to control group and recently diagnosed diabetic group. Front this study it is concluded 'hat sprthathetic nerve finwrion seems to be affecied at rho sane glyciremic status in longer duration of diabetes.

Delay in presentation, an indicator for nerve function status at registration and for treatment outcome—the experience of the Bangladesh Acute Nerve Damage Study cohort

The objective of our research was to relate delay in presentation in the Bangladesh Acute Nerve Damage Study cohort to intake status and to treatment outcome. The Bangladesh Acute Nerve Damage Study (BANDS) is a prospective cohort study of 2664 consecutive newly registered patients at clinics run by the Danish-Bangladesh Mission Leprosy (DBLM) project in Nilphamari, northern Bangladesh. The 1-year intake began in April 1995. Three-year follow-up for PB cases and 5 years for MB cases was completed in 2001. Delay in presentation in the BANDS cohort is associated with increased signs of nerve function impairment at registration. Individuals presenting with no nerve impairment and maintaining nerve function to the end of follow-up had the shortest mean delays. Individuals presenting with impairment that did not improve during follow-up had the longest mean delays. Discussion focuses on the value of setting a threshold value defining early presentation. Since the WHO Grade 2 disability rate effectively sanctions lengthy delays where there is no impairment, an indicator relating directly to delay is preferred as an indicator for good practice in leprosy control.

Limited Joint Mobility in Insulin-dependent Diabetes: Relationship to Retinopathy, Peripheral Nerve Function and HLA Status

Eighty-eight (43 per cent) of 204 patients with insulin-dependent diabetes had limited joint mobility affecting mainly the small joints of the hands. The presence of limited joint mobility correlated with duration of diabetes and with the presence of retinopathy. Patients with longstanding diabetes were approximately 2.5 times more likely to have proliferative retinopathy if limited joint mobility was present than if it was absent, although the risk for non-proliferative or background retinopathy was not increased. In patients with longstanding diabetes and limited joint mobility nerve conduction velocity and vibration perception threshold were significantly reduced compared with patients having similar duration of diabetes but normal joints. The association between insulin-dependent diabetes and HLA-DR3 and HLA-DR4 was confirmed, but there was no difference, between patients with and without limited joint mobility, in the frequency of the various HLA types. Limitation of joint mobility appears to be another "chronic complication' of diabetes, developing in parallel with retinopathy and deteriorating peripheral nerve function, and possibly of similar aetiology.

Sympathetic Nerve Function Status in Follicular and Late Luteal Phases of Menstrual Cycle in Healthy Young Women

Background: Autonomic nerve function status may be changed during follicular and late luteal phases of menstrual cycle due to fluctuations of serum estrogen and progesterone level. Objective: To observe the sympathetic nerve function status during follicular and late luteal phases of menstrual cycle and their relationships with serum estrogen and progesterone in healthy young womens. Methods: This cross-sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College, Dhaka from 1st January 2009 to 31st December 2009.A total number of thirty (30) apparently healthy unmarried women with age ranged from 20-25 years were investigated. Two simple autonomic nerve function tests, like fall of systolic blood pressure (SBP) on standing and rise of diastolic blood pressure (DBP) during handgrip were done to assess sympathetic activity. Serum estrogen and progesterone levels were also measured by AxSYM method. All these tests were performed in both follicular and late luteal phases of menstrual cycle. Data were analysed by paired student’s ‘t’ test and Pearson’s correlation coefficient test as applicable. Results: Mean resting heart rate was significantly (p<0.01) increased in late luteal phase than that of follicular phase. Mean resting systolic blood pressure was significantly (p<0.01) increased and resting diastolic blood pressure was non-significantly increased in late luteal phase than those of follicular phase. Again, significantly (p<0.05) increased value of fall of systolic blood pressure after standing from lying and non-significant increased value of rise in diastolic blood pressure after sustained handgrip were observed in late luteal phase. The mean value of serum estrogen was non-significantly and serum progesterone was significantly (p<0.001) increased in late luteal phase than those of follicular phase. Conclusion: From this study it can be concluded that sympathetic activity is increased in late luteal phase of menstrual cycle. In addition, increased sympathetic activity during late luteal phase might be the cause of premenstrual syndrome (PMS) in some women. Key words: Sympathetic nerve functions; progesterone. DOI: 10.3329/jbsp.v5i2.6782J Bangladesh Soc Physiol. 2010 December; 5(2): 80-88

Heart Rate Variability in Patients with Essential Hypertension

Background: Essential hypertension may be associated with altered cardiovascular autonomic nervefunction. Heart Rate Variability (HRV) analysis is an important tool for quantitative measurement ofautonomic nerve activity. Objective: To assess the cardiac autonomic nerve function status in essentialhypertension by analyzing time domain measures of heart rate variability. Methods: This cross sectional study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib MedicalUniversity from 1st July 2008 to 30th June 2009.For this purpose, 60 hypertensive male patients withage ranged between 40-60 years (group B) were enrolled from the Out Patient Department of Cardiology,BSMMU, Dhaka. Based on treatment received, hypertensive patients were subdivided into group B1i.e.untreated patients on their 1st day of diagnosis and group B2 i.e.patients with antihypertensivetherapy. For comparison, 30 age & sex matched apparently healthy normotensive subjects (group A)were also studied as control group. Time domain measures of Heart Rate Variability (HRV) such asMean RR intervals, Mean HR, SDNN & RMSSD were assessed by a Polygraph machine to observeboth sympathetic and parasympathetic nerve function status. For statistical analysis of data,Independent sample t-test, One-way ANOVA test, were used as applicable. Results: Mean R-R interval SDNN and RMSSD were significantly (P<0.01) lower but mean heart rate was significantly (P<0.01)higher in untreated hypertensive patients than those of normotensive subjects. But differences in allthese 4 parameters when compared between control and treated hypertensive patients were foundstatistically non significant. Conclusion: Impaired cardiac autonomic nerve function characterized bysympathetic overactivity may occur in hypertensive patients.Key words: Mean RR; SDNN; RMSSD; hypertensionDOI: 10.3329/jbsp.v5i1.5411J Bangladesh Soc Physiol. 2010 June; 5(1): 1-7

Parasympathetic Nerve Function Status During Different Phases Of Menstrual Cycle In Healthy Young Women

Background: Autonomic nerve function status may be changed during follicular and late luteal phases of menstrual cycle due to fluctuations of serum estrogen and progesterone levels. This alteration in autonomic nerve functions may affect cardiovagal control and usually associated with decreased parasympathetic activity in late luteal phase. Objective: To observe the parasympathetic nerve function status during follicular and late luteal phases of menstrual cycle and also their relationships with serum estrogen and progesterone levels in healthy young women. Methods: This cross-sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC), Dhaka from 1st January 2009 to 31st December 2009. A total number of thirty (30) apparently healthy unmarried women age ranged from 20-25 years were studied in both follicular (phase A, control) and late luteal (phase B, study) phases of menstrual cycle. Simple autonomic nerve function tests like heart rate (HR) response to valsalva maneuver (valsalva ratio), HR response to deep breathing, HR response to standing (30th:15th ratio) were done to assess parasympathetic activity and serum estrogen and progesterone levels were also measured by AxSYM method. All these tests were performed in both follicular and late luteal phases of menstrual cycle of the same subject. Data were analysed by paired student’s ‘t’ test and Pearson’s correlation coefficient test as applicable. Results: Mean values of both HR response to valsalva ratio and HR response to standing (30th:15 th ) were non-significantly decreased but HR response to deep breathing was significantly (p<0.05) decreased in late luteal phase than those of follicular phase. Conclusion: From this study it can be concluded that parasympathetic activity is decreased in late luteal phase of menstrual cycle. DOI: http://dx.doi.org/10.3329/jbsp.v6i2.9759 JBSP 2011 6(2): 100-107

Power Spectral Analysis of Heart Rate Variability in Hypertensive Male

Background: Essential hypertension is associated with altered cardiovascular autonomic nerve function. Heart Rate Variability (HRV) analysis is an important tool for quantitative measurement of autonomic nerve activity. Objective: To assess the cardiac autonomic nerve function status in essential hypertension by analyzing power spectral measures of heart rate variability. Methods: This cross sectional study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University between July 2008 and June 2009. Sixty male hypertensive patients with age range 40-60 years (group B) were enrolled from the Out Patient Department of Cardiology, BSMMU, Dhaka. Thirty age and sex matched apparently healthy normotensive subjects (group A) were studied as control, Hypertensive patients were further divided into group B1 consisting of 30 untreated patients on their 1st day of diagnosis and group B2 consisting of 30 patients under antihypertensive therapy. Power Spectral measures of Heart Rate Variability (HRV) such as total power, low frequency (LF) and high frequency power (HF) LH/HF ratio were assessed by a digital Polygraph. For statistical analysis, Independent sample t-test, One-way ANOVA test and Pearson’s correlation coefficient test were done as applicable. Results: Mean TP, LF, HF and HF norm was significantly (p<0.001) lower and LF/HF ratio and LF norm were significantly (p<0.001) higher in both untreated and treated hypertensive patients compared to those of normotensive subjects. Again, significant differences of LF norm and HF norm and LF/HF ratio were found between the two hypertensive groups. The LF/HF ratio and LF norm were positively and HF norm was negatively correlated with SBP and DBP in both the hypertensive groups. However, all these findings were more marked in untreated hypertensive patients than those of treated group. Conclusion: Sympathovagal balance in hypertensive patients is towards higher sympathetic and lower vagal modulation and effective treatment of the patients can return the balance towards normal. Key words: LF norm; HF norm; LF/HF ratio; hypertension DOI: http://dx.doi.org/10.3329/jbsp.v6i1.8082 J Bangladesh Soc Physiol. 2011 June; 6(1): 32-38

Evaluation of Parasympathetic Nerve Function Status in Healthy Elderly Subjects

Background: Autonomic control on cardiovascular activity is modified with age. Impaired autonomic nerve functions are common features of patients suffering from cardiovascular diseases particularly in old age. Objective: To observe the influence of aging process on parasympathetic nerve function. Study design: This observational study was conducted in the Department of Physiology, BSMMU, Dhaka during the period of July 2005 to June 2006. For this purpose, 60 apparently healthy elderly subjects of both sexes were selected as study group and divided into two groups-one group consisted of 30 elderly subjects with age ranged from 51-60 years and another group consisted of 30 elderly subjects with age ranged from 61-70 years. Thirty sex and BMI matched healthy adults with age ranged from 21-30 years were studied as control. Methods: Parasympathetic nerve function status of all the subjects were assessed by three simple non-invasive cardiovascular reflex tests. These were heart rate response to valsalva maneuver, heart rate response to deep breathing and heart rate response to standing (30th:15th ). For statistical analysis one way ANOVA (Post Hoc Test) and the Pearson's correlation co-efficient tests were done. Results: Mean (± SD) of valsalva ratio were 1.50±0.23, 1.32±0.14 and 1.28±0.15; HR response to deep breathing test were 25.36±3.90, 18.82±3.35 and 15.96±3.54 beats/min; 30th:15th ratio in standing test were 1.100.06, 1.05±0.03 and 1.04±0.02 in 21- 30, 51-60 and 61-70 years age groups respectively. All the 3 parameters were significantly lower in both elderly groups compared to that of control adults (p < 0.001) Again, HR response to deep breathing was significantly lower in 61-70 years age group compared to that of 51-60 years age group. Valsalva ratio and 30th:15th ratio were also lower in 61-70 years age group than that of 51-60 years group but the differences were not statistically significant. All the 3 parameters were negatively correlated with age which were statistically significant. Conclusion: From this study it may concluded that aging process substantially impaired cardiovascular parasympathetic nerve functions. Key words: Cardiovascular reflex test, elderly person.      doi: 10.3329/jbsp.v3i0.1790 J Bangladesh Soc Physiol.2008 Dec;(3):23-28.

Relationship Between Obesity And Parasympathetic Nerve Function

Back ground: Obesity is a potential risk factor for cardiovascular morbidity and mortality. As certain cardiovascular disorders associated with autonomic nerve which dysfunction often coexist in obese persons, investigations of autonomic nerve function especially parasympathetic nerve function in obese, for detection of early autonomic impairment can be potentially important to prevent complications. Objective: The present study was done to observe the parasympathetic nerve function status in obese persons in order to investigate the relationship of autonomic nerve function with obesity. Study design: This study was conducted in the department of Physiology of Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh during July 2006-June 2007. For these 40 apparently healthy obese subjects of both sexes with BMI ≥ 25 kg/sqm. were included in study group. Age and sex matched 40 apparently healthy non obese subjects with BMI range 18.5-22.9 kg/sqm. were taken as control for comparison. Methods: To assess parasympathetic nerve function status, heart rate response to valsalva(valsalva ratio), heart rate response to deep breathing and heart rate response to standing (30th:15th ratio) were determined by 3 noninvasive cardiovascular reflex tests. Data were collected by recording ECG of all subjects under test condition. The correlations of these parasympathetic nerve function parameters with BMI were also studied. Unpaired Student ‘t' test and Pearson correlation coefficient test were used for statistical analysis. Results: Valsalva ratio (1.47±0.24 vs 1.67±0.31), HR response to deep breathing (19.62±5.55 vs 27.59±6.51) and HR response to standing (1.07±0.07 vs 1.13±0.018) were significantly decreased in obese subjects than those of non obese control. All these parameters were negatively correlated with BMI. and these relatioship were statistically significant. Conclusion: The results of this study indicate that parasympathetic nerve function may be reduced in apparently healthy obese subjects. Key words: Obesity; valsalva; parasympathetic; deep breathing.  doi: 10.3329/jbsp.v3i0.1797 J Bangladesh Soc Physiol.2008 Dec;(3):50-54.

Time Domain Measures Of Heart Rate Variability In Heavy Workers

Background: Physical inactivity and low resting heart rate variability (HRV) are associated with increased incidence of coronary heart disease. Heavy physical activity is associated with higher heart rate variability and reduces the risk of coronary heart disease Objective: To assess some time domain measures of HRV in order to compare Cardiac Autonomic Function between sedentary and heavy workers. Methods: This cross sectional study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University between 1st July 2008 to 30th June 2009 on 30 apparently healthy heavy workers aged 28-50 years from low socioeconomic condition (study group). For comparison 30 age, sex, BMI and socioeconomic status matched apparently healthy sedentary subjects (group A) were also studied. The study subjects were selected among rickshaw-pullers living in the slum areas nearby BSMMU, Dhaka and the controls were from fourth class employee of BSMMU, Dhaka. Heart Rate Variability were assessed by a Polygraph. Several time domain measures of HRV such as mean R-R interval, mean HR, SDNN, RMSSD were analyzed. For statistical analysis, Independent-Samples t-test, and Pearson’s correlation coefficient tests were done as applicable. Results: Resting mean heart rate (P<0.01), SDNN (P<0.01) and RMSSD (P<0.001) were significantly lower but mean R-R interval (P<0.001) was significantly higher in heavy workers than those of sedentary control. The mean R-R interval (P<0.05) showed significant positive correlation in heavy workers but significant negative correlation in sedentary workers with BMI. Conclusion: Cardiac autonomic nerve function status may be higher with parasympathetic dominance by increased physical activity. DOI: http://dx.doi.org/10.3329/jbsp.v6i2.9755 JBSP 2011 6(2): 77-83