As many as a third of patients may suffer from "white coat syndrome" when they are undergoing treatment for high blood pressure, according to a new analysis.
The problem means that doctors think blood pressure drugs are not working – when in fact patients are largely suffering from stress at being tested.
The findings underline recent UK guidelines which urge monitoring over an extended period to establish blood pressure levels – to get round "white coat syndrome."
The findings, from a study in Spain, were reported last night in the journal Hypertension.
Researchers analysed blood pressure readings from 69,000 patients previously diagnosed with hypertension – high blood pressure.
More than 8,000 of these were thought to have "resistant hypertension", meaning their blood pressure was not responding to drugs. But after they were monitored for 24 hours, as many as 37 per cent were found to have merely suffered from white coat syndrome.
Researcher Dr Alejandro de la Sierra, of the Hospital Mutua Terrassa, Barcelona, said the findings suggested "ambulatory" blood pressure monitoring should always be used for these patients.
He said: "Patients benefit by knowing whether their blood pressure is normal during daily activities or still needs the reinforcement of dietary and drug measures to achieve the goal."
British experts said the findings added weight to the new UK guidelines.
Ellen Mason, a heart nurse with the British Heart Foundation, said: "Visiting the doctor seemed to make some people falsely appear resistant to the effects of these drugs so the study was helpful in trying to identify which people seemed to be truly resistant and therefore more at risk of organ damage."
She said it was still a bigger problem that high blood pressure remains undetected in many people.
She said: "While the increasing use of home blood pressure monitoring is helpful for some, it will not target those who are unaware of the silent condition because it may have been many years since they had their blood pressure taken or because they simply think they are not at risk."
Alejandro de la Sierra et al. Hypertension: Journal of the American Heart Association. March 28 2011. HYPERTENSION/2010/168948.
Leave a Reply