Barcelona, Spain - A new large study has found that a third of patients thought to be resistant to antihypertensive medication actually had white-coat hypertension.
"Patients with normal ambulatory blood pressure will probably have no benefit of increasing antihypertensive treatment, but an exaggerated blood-pressure reduction would be dangerous for cerebral and cardiac normal perfusion," lead investigator Dr Alejandro de la Sierra (University of Barcelona, Spain) said in an interview. "Ambulatory blood-pressure monitoring should be considered in all hypertensives showing resistance to treatment."
The results are published online March 28, 2011 in Hypertension .
Using data from the Spanish Ambulatory Blood Pressure Monitoring Registry, investigators identified more than 68 000 patients with hypertension receiving treatment.
Of these, 12% had resistant hypertension. This was defined as an office blood pressure of >140/90 mm Hg while receiving three or more antihypertensive drugs, including a diuretic.
After ambulatory blood-pressure monitoring, 63% of patients were identified as treatment resistant; the remaining 38% had white-coat hypertension.
Those resistant to treatment were more likely to be males with longer-duration hypertension. They were also more likely to be smokers and have diabetes and organ damage, including left ventricular hypertrophy, impaired renal function, microalbuminuria, and documented cardiovascular disease.
The investigators report that true resistant hypertensives were more likely to have a riser pattern (22% vs 18%, p<0.001).
"Our study provides an estimation of the prevalence of resistant hypertension in a huge number of patients reflecting the usual-care hypertensive population," de la Sierra explained. "It highlights the importance of ambulatory blood-pressure monitoring to correctly categorize patients with resistant hypertension and separate those who need treatment intensification."
During an interview, American Heart Association spokesperson Dr Donald LaVan said that physicians have good reason to be concerned about hypertension, and he pointed out that even white-coat-inspired peaks can be dangerous. "When pressures are way up—even temporarily—the vascular burden is high."
de la Sierra said his team will continue to follow their patients with white-coat peaks to obtain outcome data to help determine best management options.
|The Spanish Ambulatory Blood Pressure Monitoring Registry is funded by an unrestricted grant from Lacer Laboratories. The authors of this study have participated in educational meetings paid for by Lacer.|
Heartwire from Medscape © 2011
Cite this: White-coat hypertension can masquerade as treatment resistance - Medscape - Apr 01, 2011.