Associate Professor / Reader
At the Physiology department office
Appointment on Visitation important
Topic: Determinants Of Hypertension - Cardiovascular/Renal Physiology
Introduction: The main focus of my research is on the Determinants of Hypertension. Traditionally, hypertension is described as Essential or Primary for those for which no primary cause is discernible; and Secondary for those for which a primary cause is readily noticeable.
One of my research focus is in teasing out those individuals that are salt-sensitive and therefore have salt sensitive hypertension which is fast becoming a recognisable sub-section of Primary hypertension. This includes researching into the various genetic determinants of salt sensitivity in black individuals as well as environmental influences.
Contribution to Knowledge:
I have demonstrated the effect of a high salt diet on the baroreceptors and chemoreceptors as well as the fact that there is an interaction between the carotid chemoreceptors and baroreceptors which is not a simple summative one.
My work has also shown that salt-sensitivity is present among both normotensive (34%) and hypertensive (56%) Nigerians. Salt sensitivity leads to increased morbidity and mortality irrespective of the blood pressure of the individual.
By doing some DNA work, I have established the presence of epithelial sodium channel (ENaC) polymorphisms in 5% of the population studied. The beta-ENaC polymorphism is implicated in the poor sodium handling present in salt-sensitive individuals and it is coupled with low renin observed in most hypertensives in our populace
In recent times, I have demonstrated the role of sympathetic autonomic stress in the development of hypertension. I have shown that hyperreactivity exists among both normotensive and hypertensive individuals. Hyperreactivity is a predictor of future development of hypertension and of cardiovascular events such as strokes. I have shown too that sympathetic autonomic stress is an important determinant and not a result of hypertension. It affects left ventricular function, rate pressure product (yet to be published) and thus myocardial oxygen consumption and cardiac workload.
By studying the effect of adrenomedullin in normotensive and hypertensive volunteers under sympathetic stress, I have shown that the peptide may be important in preventing hypertension in black individuals.
Indeed, I have reported that some of our population are both salt-sensitive and hyperreactive which means they are twice as likely to suffer from hypertension and the consequent cardiovascular events. Since hypertension is a modifiable risk factor, with aggressive medical education, counselling and monitoring may prevent or moderate the course of the disease in such individuals.
|1.||Ph.D (Physiology/Cardiovascular Physiology)||University of Lagos, Lagos, Nigeria||2012|
COVID-19 and its effects on Endothelium in HIV-Positive Patients in Sub-Saharan Africa: Cardiometabolic Risk, Thrombosis and Vascular Function (ENDOCOVID STUDY)
Introduction: Sub-Saharan African (SSA) populations are increasingly facing a double burden of disease involving the interaction between HIV-AIDS and non-communicable diseases (NCDs) such as cardiovascular diseases. The recent danger posed by Covid-19 infections has increased the risks even further in these patients. The PLWH who are on antiretroviral therapy (ART) with a normal CD4 T-cell count and suppressed viral load may not be at an increased risk of severe Covid-19 infection. On the other hand, ART could also have effect on Covid-19 and many HIV-infected patients may additionally suffer from co-morbidities potentially increasing their risk for Covid-19 infection. Currently, there are no data about SARS-CoV-2 infection in PLWH in SSA to better understand who is at particular high risk for Covid-19 infections complications and fatal outcomes.
Aim/Objectives: To determine the effect of SARS-CoV-2 infection on cardiometabolic parameters and vascular function in HIV-positive patients with or without antiretroviral therapy in Nigeria as part of a multi-centre study.
Methods: Three groups of participants will be studied: PLWH without antiretroviral therapy but with SARS-CoV-2 infection; PLWH with antiretroviral therapy and SARS-CoV-2 infection and recently diagnosed ART-naïve HIV patients.
Results: Study is still in progress
Contribution to Knowledge: This study provides an opportunity to study HIV-infected patients with or without ART and HIV-negative controls co-infected with SARS-CoV-2. It also aims to establish networks for African clinicians and researchers supporting capacity building (North-South and South-South networking), while incorporating gender and cultural dimensions.
ELIAS SIMIAT is a Associate Professor / Reader at the Department of Physiology
ELIAS has a Ph.D in Physiology/Cardiovascular Physiology from University of Lagos, Lagos, Nigeria