Nearly 40% of Resistant HT Was White Coat

Major Finding: Among 8,295 patients with resistant office hypertension, 63% had ambulatory 24-hour blood pressure values greater than or equal to 130 mm Hg systolic and/or 80 mm Hg diastolic and were diagnosed as true resistant hypertension, whereas 37% showed 24-hour BP values below this limit and therefore were considered to have white-coat resistant HT.

Data Source: An analysis of data on more than 68,000 patients in the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry.

Disclosures: The Spanish ABPM Registry was initiated and is maintained by Lacer Laboratories. The authors disclosed having attended meetings funded by Lacer.

Up to 37% of resistant office hypertension is actually white-coat hypertension, according to an analysis of ambulatory blood pressure monitoring data from more than 8,000 patients.

Meanwhile, the remaining 63% who are truly resistant have a starkly worse clinical profile than do their white-coat counterparts, including significantly higher likelihoods of smoking, and having diabetes, left ventricular hypertrophy, microalbuminuria, and cardiovascular disease.

Dr. Alejandro de la Sierra of the University of Barcelona and colleagues, looked at 2009 data from the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry, which included 68,045 patients with good-quality office BP data, ambulatory BP data, and information about prescribed antihypertensives, including at least one diuretic.

Ambulatory BP measurements were acquired using an automated, noninvasive oscillometric device placed by a physician, and which registered BP at 20-minute intervals over a 24-hour period.

Patients returned the following day to their doctors for removal of the device.

Overall, 12% of participants in the registry (8,295 patients; 51% male, mean age 64 years) met Dr. de la Sierra's criteria for resistant hypertension (RH): office BP greater than or equal to 140 mm Hg systolic and/or 90 mm Hg diastolic while being treated with three or more antihypertensive agents at “appropriate” doses.

ABPM patients were classified in two groups: 5,182 patients (62.5%) had ambulatory 24-hour BP values greater than or equal to 130 and/or 80 mm Hg and were diagnosed as true RH, and 3,113 patients (37.5%) showed 24-hour BP values below this limit and were considered as having white-coat RH, wrote the authors (Hypertension 2011 March 28 [doi: 10.1161/HYPERTENSIONAHA. 110.168948]).

White-coat RH patients were slightly but significantly older (65 vs. 64 years), and more likely to be female (54%).

Truly resistant patients, however, were more likely to be smokers (15% vs. 10%), to be diabetic (35% vs. 28%), and to have cardiovascular disease (19% vs. 16%), compared with the white-coat RH patients. Moreover, 19% of the true RH patients had left ventricular hypertrophy, as seen on an electrocardiogram, vs. 14% of white-coat patients.

They also had higher creatinine levels than did their white-coat counterparts (75 vs. 72 micromol/L), higher urinary albumin excretion (11 vs. 7 mg/g), and a higher percentage of patients with a urinary albumin excretion greater than 30 mg/g (30% vs. 20%).

Body mass index and total cholesterol did not vary significantly between groups.

According to the authors, the study represents the first time that the prevalence of resistant hypertension was assessed in such a large cohort of patients.

However, the researchers pointed to one major weakness of the study: the inability to confirm that patients prescribed antihypertensive drugs were adherent to their medication regimen, “thus possibly overestimating the true prevalence of RH.”

And despite the findings of significant differences in clinical characteristics between groups, “their discriminating value in clinical practice is probably low,” cautioned the authors.

Major Finding: Among 8,295 patients with resistant office hypertension, 63% had ambulatory 24-hour blood pressure values greater than or equal to 130 mm Hg systolic and/or 80 mm Hg diastolic and were diagnosed as true resistant hypertension, whereas 37% showed 24-hour BP values below this limit and therefore were considered to have white-coat resistant HT.

Data Source: An analysis of data on more than 68,000 patients in the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry.

Disclosures: The Spanish ABPM Registry was initiated and is maintained by Lacer Laboratories. The authors disclosed having attended meetings funded by Lacer.

Up to 37% of resistant office hypertension is actually white-coat hypertension, according to an analysis of ambulatory blood pressure monitoring data from more than 8,000 patients.

Meanwhile, the remaining 63% who are truly resistant have a starkly worse clinical profile than do their white-coat counterparts, including significantly higher likelihoods of smoking, and having diabetes, left ventricular hypertrophy, microalbuminuria, and cardiovascular disease.

Dr. Alejandro de la Sierra of the University of Barcelona and colleagues, looked at 2009 data from the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry, which included 68,045 patients with good-quality office BP data, ambulatory BP data, and information about prescribed antihypertensives, including at least one diuretic.

Ambulatory BP measurements were acquired using an automated, noninvasive oscillometric device placed by a physician, and which registered BP at 20-minute intervals over a 24-hour period.

Patients returned the following day to their doctors for removal of the device.

Overall, 12% of participants in the registry (8,295 patients; 51% male, mean age 64 years) met Dr. de la Sierra's criteria for resistant hypertension (RH): office BP greater than or equal to 140 mm Hg systolic and/or 90 mm Hg diastolic while being treated with three or more antihypertensive agents at “appropriate” doses.

ABPM patients were classified in two groups: 5,182 patients (62.5%) had ambulatory 24-hour BP values greater than or equal to 130 and/or 80 mm Hg and were diagnosed as true RH, and 3,113 patients (37.5%) showed 24-hour BP values below this limit and were considered as having white-coat RH, wrote the authors (Hypertension 2011 March 28 [doi: 10.1161/HYPERTENSIONAHA. 110.168948]).

White-coat RH patients were slightly but significantly older (65 vs. 64 years), and more likely to be female (54%).

Truly resistant patients, however, were more likely to be smokers (15% vs. 10%), to be diabetic (35% vs. 28%), and to have cardiovascular disease (19% vs. 16%), compared with the white-coat RH patients. Moreover, 19% of the true RH patients had left ventricular hypertrophy, as seen on an electrocardiogram, vs. 14% of white-coat patients.

They also had higher creatinine levels than did their white-coat counterparts (75 vs. 72 micromol/L), higher urinary albumin excretion (11 vs. 7 mg/g), and a higher percentage of patients with a urinary albumin excretion greater than 30 mg/g (30% vs. 20%).

Body mass index and total cholesterol did not vary significantly between groups.

According to the authors, the study represents the first time that the prevalence of resistant hypertension was assessed in such a large cohort of patients.

However, the researchers pointed to one major weakness of the study: the inability to confirm that patients prescribed antihypertensive drugs were adherent to their medication regimen, “thus possibly overestimating the true prevalence of RH.”

And despite the findings of significant differences in clinical characteristics between groups, “their discriminating value in clinical practice is probably low,” cautioned the authors.

Major Finding: Among 8,295 patients with resistant office hypertension, 63% had ambulatory 24-hour blood pressure values greater than or equal to 130 mm Hg systolic and/or 80 mm Hg diastolic and were diagnosed as true resistant hypertension, whereas 37% showed 24-hour BP values below this limit and therefore were considered to have white-coat resistant HT.

Data Source: An analysis of data on more than 68,000 patients in the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry.

Disclosures: The Spanish ABPM Registry was initiated and is maintained by Lacer Laboratories. The authors disclosed having attended meetings funded by Lacer.

Up to 37% of resistant office hypertension is actually white-coat hypertension, according to an analysis of ambulatory blood pressure monitoring data from more than 8,000 patients.

Meanwhile, the remaining 63% who are truly resistant have a starkly worse clinical profile than do their white-coat counterparts, including significantly higher likelihoods of smoking, and having diabetes, left ventricular hypertrophy, microalbuminuria, and cardiovascular disease.

Dr. Alejandro de la Sierra of the University of Barcelona and colleagues, looked at 2009 data from the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry, which included 68,045 patients with good-quality office BP data, ambulatory BP data, and information about prescribed antihypertensives, including at least one diuretic.

Ambulatory BP measurements were acquired using an automated, noninvasive oscillometric device placed by a physician, and which registered BP at 20-minute intervals over a 24-hour period.

Patients returned the following day to their doctors for removal of the device.

Overall, 12% of participants in the registry (8,295 patients; 51% male, mean age 64 years) met Dr. de la Sierra's criteria for resistant hypertension (RH): office BP greater than or equal to 140 mm Hg systolic and/or 90 mm Hg diastolic while being treated with three or more antihypertensive agents at “appropriate” doses.

ABPM patients were classified in two groups: 5,182 patients (62.5%) had ambulatory 24-hour BP values greater than or equal to 130 and/or 80 mm Hg and were diagnosed as true RH, and 3,113 patients (37.5%) showed 24-hour BP values below this limit and were considered as having white-coat RH, wrote the authors (Hypertension 2011 March 28 [doi: 10.1161/HYPERTENSIONAHA. 110.168948]).

White-coat RH patients were slightly but significantly older (65 vs. 64 years), and more likely to be female (54%).

Truly resistant patients, however, were more likely to be smokers (15% vs. 10%), to be diabetic (35% vs. 28%), and to have cardiovascular disease (19% vs. 16%), compared with the white-coat RH patients. Moreover, 19% of the true RH patients had left ventricular hypertrophy, as seen on an electrocardiogram, vs. 14% of white-coat patients.

They also had higher creatinine levels than did their white-coat counterparts (75 vs. 72 micromol/L), higher urinary albumin excretion (11 vs. 7 mg/g), and a higher percentage of patients with a urinary albumin excretion greater than 30 mg/g (30% vs. 20%).

Body mass index and total cholesterol did not vary significantly between groups.

According to the authors, the study represents the first time that the prevalence of resistant hypertension was assessed in such a large cohort of patients.

However, the researchers pointed to one major weakness of the study: the inability to confirm that patients prescribed antihypertensive drugs were adherent to their medication regimen, “thus possibly overestimating the true prevalence of RH.”

And despite the findings of significant differences in clinical characteristics between groups, “their discriminating value in clinical practice is probably low,” cautioned the authors.