Avupati Naga Syamsunder1, Pravati Pal1, Gopal Krushna Pal1, Chandrakasan Sadishkumar Kamalanathan2, Subhash Chandra Parija3, Nivedita Nanda4, Allampalli Sirisha1. 1. a Department of Physiology , Jawaharlal Institute of Post-graduate Medical Education and Research (JIPMER) , Puducherry , India. 2. b Department of Endocrinology , Jawaharlal Institute of Post-graduate Medical Education and Research (JIPMER) , Puducherry , India. 3. c Department of Microbiology , Jawaharlal Institute of Post-graduate Medical Education and Research (JIPMER) , Puducherry , India. 4. d Department of Biochemistry , Jawaharlal Institute of Post-graduate Medical Education and Research (JIPMER) , Puducherry , India.
Abstract
Purpose/aim of the study: The present study investigated the link of hyperlipidemia, inflammation and oxidative stress (OS) to cardiovascular (CV) risks in subclinical hypothyroidism (SCH). MATERIALS AND METHODS: We enrolled 81 subclinical hypothyroid patients and 80 healthy subjects as control. Their CV and autonomic functions were assessed by spectral analysis of heart rate variability (HRV), continuous blood pressure variability (BPV) measurement and conventional autonomic function testing. Thyroid profile, lipid profile, immunological, inflammatory and OS markers were estimated and correlated with the baro-reflex sensitivity (BRS), the marker of sympathovagal imbalance (SVI) & CV risk. RESULTS: Mean arterial pressure (MAP, P<0.0001), total peripheral resistance (TPR, P<0.0001), ratio of low-frequency to high-frequency power of HRV (LF-HF ratio) (P<0.0001) were significantly higher and BRS (P<0.0001) was significantly lower in SCH group than the control group. BRS significantly correlated with heart rate, MAP, LF-HF ratio, lipid risk factors, anti-thyroperoxidase antibody, thyroid-stimulating hormone, high-sensitive C-reactive protein (hsCRP), malondialdehyde (MDA) and SCH. CONCLUSIONS: It was concluded that SVI is associated with SCH. Though dyslipidemia, inflammation and OS contributed to decreased BRS, SCH per se contributed maximally to it. Decreased BRS could be a physiological basis of increased CV risks in patients with SCH.
Purpose/aim of the study: The present study investigated the link of hyperlipidemia, inflammation and oxidative stress (OS) to cardiovascular (CV) risks in subclinical hypothyroidism (SCH). MATERIALS AND METHODS: We enrolled 81 subclinical hypothyroidpatients and 80 healthy subjects as control. Their CV and autonomic functions were assessed by spectral analysis of heart rate variability (HRV), continuous blood pressure variability (BPV) measurement and conventional autonomic function testing. Thyroid profile, lipid profile, immunological, inflammatory and OS markers were estimated and correlated with the baro-reflex sensitivity (BRS), the marker of sympathovagal imbalance (SVI) & CV risk. RESULTS: Mean arterial pressure (MAP, P<0.0001), total peripheral resistance (TPR, P<0.0001), ratio of low-frequency to high-frequency power of HRV (LF-HF ratio) (P<0.0001) were significantly higher and BRS (P<0.0001) was significantly lower in SCH group than the control group. BRS significantly correlated with heart rate, MAP, LF-HF ratio, lipid risk factors, anti-thyroperoxidase antibody, thyroid-stimulating hormone, high-sensitive C-reactive protein (hsCRP), malondialdehyde (MDA) and SCH. CONCLUSIONS: It was concluded that SVI is associated with SCH. Though dyslipidemia, inflammation and OS contributed to decreased BRS, SCH per se contributed maximally to it. Decreased BRS could be a physiological basis of increased CV risks in patients with SCH.
Authors: Heberto Suarez-Roca; Rebecca Y Klinger; Mihai V Podgoreanu; Ru-Rong Ji; Martin I Sigurdsson; Nathan Waldron; Joseph P Mathew; William Maixner Journal: Anesthesiology Date: 2019-04 Impact factor: 7.892