A doctor from Dublin is working with researchers in Birmingham to understand why patients with high blood pressure have impaired pain perception. She hopes to develop a way of predicting who will develop dangerously high blood pressure in the future, writes Vikki Burns
"There is evidence that people with increased blood pressure don't feel pain as much as those with normal blood pressure," says Dr Una Martin, lecturer in clinical pharmacology at the University of Birmingham. Her research examines this phenomenon with Dr Louisa Edwards and Dr Christopher Ring from the school of sport and exercise sciences.
Volunteers with high blood pressure (hypertension) and normal healthy controls were given brief electrical stimulations to the ankle to elicit pain. The experiments were conducted at the Wellcome Trust clinical research facility in Birmingham.
"The level of stimulation was increased until they felt that they could no longer tolerate the pain. We then asked how painful they had found the procedure," explains Edwards.
"The patients with hypertension didn't differ from the control participants in terms of the amount of pain they could tolerate but, when asked how they felt, they rated the procedure as less painful," she continues. These results were recently presented at the joint international meeting of the Physiological Society and the Federation of European Physiological Societies.
"We are interested in whether this is an isolated problem in perceiving pain or part of a global impairment of higher functions, such as memory," says Dr Martin.
"If so, it may precede the onset of hypertension and could be used as a tool to identify at-risk populations," she says.
Hypertension affects more than a quarter of the world's adult population and contributes to predictions of a worldwide epidemic of cardiovascular disease, according to recent reports.
"If we can identify the people that might get hypertension in the future, we can intervene earlier," says Martin, who trained in medicine at University College Dublin.
Possible interventions to prevent hypertension would include "reducing salt intake, increasing exercise levels, decreasing alcohol consumption and adopting healthy eating patterns".
Dr Vikki Burns is a scientist from the University of Birmingham on placement at The Irish Times as a British Association for the Advancement of Science Media Fellow