effect of gag reflex on cardiac sympatovagal tone

Heart velocity may be influenced by gagging. The medulla oblongata receives the afferents of gag reflex. Neuronal pools of vomiting, salivation and cardiac parasympathetic fibers are very close in this area. So, their activities may be changed by spillover from each other. Using the heart rate variability [HRV] analysis, the effect of gagging on cardiac sympatovagal balance was studied. ECG was recorded from 12 healthy nonsmoker volunteer students for 10 minutes in the sitting position between 10 and 11 AM. Gagging was elicited by tactile stimulation of the posterior pharyngeal wall. At 1 kHz sampling rate, HRV was calculated. The mean of heart rate at low and high frequencies [LF: 0.04-0.15; HF: 0.15-0.4 Hz] were compared before and after the stimulus. The mean of average heart rate, LF and HF in normalized units [nu] and the ratio of them [LF/HF] before and after the gagging were 89.9 +/- 3 and 95.2 +/- 3 bpm; 44.2 +/- 5.8 and 21.2 +/- 4; 31.1 +/- 5.3 and 39.4 +/- 3.8; and 1.7 +/- 0.3 and 0.6 +/- 0.2 respectively. Gagging increased heart velocity and had differential effect on two branches of cardiac autonomic nerves. The paradoxical relation between average heart rate and HRV indexes of sympatovagal tone may be due to unequal rate of change in autonomic fiber activities which is masked by 5 minutes interval averaging

[Prevalence and risk factors of osteoporosis in postmenopausal women with rheumatoid arthritis: a brief report]

Low bone mass is a serious health problem mostly seen in postmeno-pausal women with rheumatoid arthritis. The purpose of this study was to determine the prevalence of osteoporosis and some related risk factors in postmenopausal women with rheumatoid arthritis. The data for this descriptive analytical study was extracted from the medical records of 98 postmenopausal women with rheumatoid arthritis who had attended the 5th of Azar Teaching Hospital affiliated to Gorgan University of Medical Sciences, in Iran, in 2009. The mean durations of menopause and rheumatoid arthritis were 9.39 and 5.13 years, respectively. The overall prevalence of osteoporosis was 13.3%. We found a significant correlation between age, disease duration, and duration of menopause with bone mineral density [P < 0.05]. Our results indicate a high prevalence of osteoporosis at the lumbar spine of postmenopausal women with rheumatoid arthritis