Abstract
Introduction: Post menopausal women are more prone to hypothyroidism as well as for cardiovascular ailments. Autonomic dysfunction or sympathovagal imbalance may contribute to cardiovascular morbidity in postmenopausal hypothyroid patients.
Materials and Methods:Twenty healthy post menopausal women and twenty post menopausal women with hypothyroidism were enrolled for the study as control and cases respectively. Their autonomic status has been recorded as HRV for parasympathetic and hand grip test for sympathetic activity. Thyroid status was examined by RIA.
Result: Comparison of TSH level with HRV in both control and cases are found to be insignificant (P value 0.4317 and 0.3429 respectively). But the comparison between TSH with handgrip exercise is found to be significant in case group (P value <0.0001 and 0.0077) for both for systolic and diastolic BP.
Discussion: Though comparison between TSH with HRV of both control and cases are insignificant but the mean values of R-R interval of HRV decreases in cases than the control. So there is a vagal inhibition in hypothyroid group.
Conclusion: Sympathovagal imbalance due to sympathetic activation and vagal inhibition occurs in hypothyroidism.
Keywords: Autonomic nervous system, hand grip, HRV, hypothyroidism.
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DOI: http://dx.doi.org/10.18535/jmscr/v4i2.78
