Rita Khadka

Introduction: Cardiovascular diseases and cholesterol levels are increased postmenopausal/perimenopausal women. Cardiac autonomic tone as assessed with heart rate variability (HRV) is also altered in postmenopausal women. Yoga practice improves vasomotor symptoms in postmenopausal women. Whether yoga can improve HRV and cholesterol levels in perimenopausal women is not clear. Methods: Sixty perimenopausal women, not on any medication, were randomized into two groups; yoga (n=30, age 44±2.64 years) and control (n=30, age 46±5.09 years). The yoga group practiced meditation, pranayama, and few simple asanas for 40 min/day, 6 days/week for four weeks along with their daily routine activities. The control group practiced no additional exercises except their daily routine activities. Short-term HRV, lipid profile, and other biochemical parameters were assessed at the beginning and after four weeks and compared. Results: Both groups were comparable in terms of their age body mass index (BMI), blood pressure (BP), heart rate (HR), and respiratory rate at 0 week. The yoga group showed a decrease in BMI, HR, systolic BP, total cholesterol [167.81±32.69 vs 144.46±26.98 mg/dl, p=0.013], LDL-cholesterol [118.19±28.25 vs 94.33±23.55 mg/dl, 0.002]; and an increase in HDL-cholesterol (49.62±6.34 vs 56.37±8.19 mg/dl, p=0.004), markers of cardiac parasympathetic tone [SDNN {33.3(24.35-40.1) vs 43.2(34.4-50.1) ms, p=0.041}, rMSSD {25.2(21.95-33.05) vs 30.6(25.1-38.0) ms, p=0.034}, and high frequency power] after four weeks of yoga practice. Conclusion: Parasympathetic tone and HDL-cholesterol increased, whereas total and LDL-cholesterol, BMI, HR, and systolic BP decreased in perimenopausal women after four weeks of yoga practice. It is suggested that yoga can be a cardio-protective alternative therapeutic measure in perimenopausal women.

Angina is a type of chest pain, experienced by patients with ischemic heart diseases. Cardiac autonomic modulation as assessed by heart rate variability and baroreflex sensitivity is found reduced in ischemic heart disease patients. Marked reduction in heart rate variability and baroreflex sensitivity in ischemic heart disease patients is found associated with sudden cardiac death. We report a case of a 35-year-old man who presented with angina for the last few months. Thorough investigations showed no evidence of any cardiac or other systemic diseases. However, his cardiovascular autonomic modulation (as assessed by heart rate variability) and spontaneous baroreflex sensitivity were markedly reduced. The patient had sudden death within 6 months of follow-up. Reportedly, no other specific abnormalities were found before death. This case report suggests that patients presenting with typical chest pain as angina may have severe dysautonomia and risk of sudden death even in the absence of cardiovascular or any other known end-organ diseases.

Despite the successful adaptation to high altitude, some differences do occur due to long term exposure to the hypoxic environment. The effect of long term high altitude exposure on cardiac autonomic adjustment during basal and post-exercise recovery is less known. Thus we aimed to study the differences in basal cardiac autonomic adjustment and its response to exercise in highlanders and to compare it with lowlanders. The study was conducted on 29 healthy highlander males who were born and brought up at altitude of 3000 m and above from the sea level, their cardiac autonomic adjustment was compared with age, sex, physical activity and ethnicity-matched 29 healthy lowlanders using Heart Rate Variability (HRV) during rest and recovery from sub-maximal exercise (3 m step test). Intergroup comparison between the highlanders and lowlanders and intragroup comparison between the rest and the postexercise recovery conditions were done. Resting heart rate and HRV during rest was comparable between the groups. However, heart rate recovery after 3 min step test was faster in highlanders (p < 0.05) along with significantly higher LF power and total power during the recovery phase. Intragroup comparison of highlanders showed higher SDNN (p < 0.05) and lower LF/HF ratio (p < 0.05) during recovery phase compared to rest which was not significantly different in two phases in lowlanders. Further highlander showed complete recovery of RMSSD, NN50, pNN50 and HF power back to resting level within five minutes, whereas, these parameters failed to return back to resting level in lowlanders within the same time frame. Highlanders completely recovered back to their resting state within five minutes from cessation of step test with parasympathetic reactivation; however, recovery in lowlanders was delayed.

Article: Nerve conduction studies in lower limb of elite Nepalese football players: an insight into neural adaptations - The Journal of Sports Medicine and Physical Fitness 2017 March;57(3):313-8 - Minerva Medica - Journals

Reports on alterations in somatic neural functions due to non-diabetic obesity, a major risk factor for diabetes, are few and still a matter of debate. Nevertheless, to our knowledge, reports lack any comments on the type of somatic nerve fibers affected in non-diabetic obesity. Therefore, this study aimed to find out the alteration in somatic neural functions in non-diabetic obese persons if any. The study was conducted on 30 adult non-diabetic obese persons (mean age 32.07 ± 7.25 years) with BMI > 30 Kg/m2 (mean BMI 30.02 ± 2.89 Kg/m2) and 29 age- and sex-matched normal weight controls (mean age 30.48 ± 8.01 years) with BMI: 18–24Kg/m2 (mean BMI 21.87 ± 2.40 Kg/m2). Nerve conduction study (NCS) variables of median, tibial and sural nerves were assessed in each subject using standard protocol. The data were compared by Mann Whitney ‘U’ test. In comparison to normal weight persons, obese had lower compound muscle action potential (CMAP) amplitudes of right median [9.09(7.62–10.20) Vs 10.75(8.71–12.2) mV, p = 0.025] and bilateral tibial nerves [Right: 8.5(7.04–11.18) Vs 12.1(10.55–15) mV, p < 0.001 and left 9.08(6.58–11.65) Vs 13.05(10.2–15.6) mV, p = 0.002]. Furthermore, obese persons had prolonged CMAP durations of right and left median [10.5(9.62–12) Vs 10(8.4–10.3) ms, p = 0.02 and 10.85(10–11.88) Vs 10(9–10.57) ms, p = 0.019] and right tibial [10(9–11) 8.5(7.92–10) ms, p = 0.032] nerves. Sensory NCS (sural nerve) also showed diminished sensory nerve action potential (SNAP) amplitude [16(12.08–18.21) vs 22.8(18.3–31.08) μV, p < 0.001] and prolonged duration. However, onset latencies and conduction velocities for all nerves were comparable between the groups. This study documents subclinical peripheral nerve damage in non-diabetic obese with abnormal NCS parameters; shorter amplitudes and prolonged CMAP and SNAP durations. The reduced amplitudes of mixed and sensory nerves might be due to decreased axonal number stimulation or actual decrease in number of axonal fibers, or defect at NMJ in non-diabetic obese. Prolonged durations but normal onset latencies and conduction velocities strongly suggest involvement of slow conducting fibers.

Background The medical and dental studies are believed to be demanding and stressful. Objectives The objectives of this study were to compare stressors between medical and dental students and to find out the relationship among entrance examination marks, cognitive function and stressors during their first year of studies. Methods The marks obtained by the medical (n=91) and dental (n=33) students (aged 18–28 years) in their common entrance examination, primarily in physics, chemistry and biology, were documented. Their stressors were assessed by using Medical Student Stressor Questionnaire (MSSQ) along with additional modified structured questionnaire. The cognitive function assessment (CFA) score was assessed by the standardised questionnaire constituting 40 marks. The medical and dental students were compared based on their entrance examination marks, the CFA score and the MSSQ using independent sample t-test. Pearson's correlation was done among the three groups of variables. Results Stressors and degree of stress between medical and dental students were similar. Both the groups of students perceived moderate-to-high degree of stress related to academics (45.55 vs. 41.17%) and inter-and intrapersonal conflict (50 vs. 50%), while the other stressors were of mild-to-moderate level. In addition, the CFA score was negatively correlated (r= -0.2, P=0.046) with teaching and learning-related stressor. The CFA score was found to behigher in medical than in dental students (24 ± 6.1 vs. 21 ± 5.7; P= 0.007), possibly linked to better performance by the medical students in their entrance examination (142.71±26.69 vs. 123.76±24.74; P=0.001) compared with that of the dental students. Conclusion The medical students are high achievers in the entrance examination than the dental students. However, their academic-related, inter- and intrapersonal-related stressors were of moderate-to-high degree. The teaching and learning-related stress is directly linked to cognitive function: less stress in students with high cognitive function in them.