Blood Pressure Control and Physician Management of Hypertension in Hospital Hypertension Units in Spain
Goal blood pressure (BP) was defined by the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-VI) and the World Health Organization–International Society of Hypertension (WHO/ISH) as <140 mm Hg systolic and <90 mm Hg diastolic for the general and <130 mm Hg systolic and <85 mm Hg diastolic for special high-risk populations. However, there are few reports that address BP control among special subgroups of hypertensives by reference to targeted BP. We therefore conducted a study to evaluate BP control of 4049 hypertensives in 47 hospital-based hypertension units in Spain. Overall, 42% of patients achieved goal BP (<140 mm Hg systolic and <90 mm Hg diastolic). Only 13% of diabetic patients and 17% of those with renal disease achieved the BP goal (<130 mm Hg systolic and <85 mm Hg diastolic), and only 10% and 12%, respectively, achieved the even more rigorous goal (<130 mm Hg systolic and <80 mm Hg diastolic). Likewise, only 18% of patients in JNC-VI risk group C and 17% of WHO/ISH high-risk patients attained a goal BP <130 mm Hg systolic and <85 mm Hg diastolic. BP control (<125 mm Hg systolic and <75 mm Hg diastolic) was extremely low (2%) in patients with proteinuria >1 g/d. Poorer BP control was observed among patients at high risk, with diabetes, renal disease, or obesity, than in lower-risk groups. BP control was lower for systolic than for diastolic BP. In >50% of uncontrolled patients, no measures were taken by doctors to optimize pharmacologic treatment, and approximately one-third of patients were still using drug monotherapy. Control of BP, particularly of systolic BP, is still far from optimal in hospital-based hypertension units. Patients at high risk, with diabetes or proteinuria, warrant focused attention. Moreover, a more aggressive behavior of doctors treating uncontrolled hypertension is needed.
Epidemiological surveys have revealed that blood pressure (BP) control is adequate (<140 mm Hg systolic BP [SBP] and <90 mm Hg diastolic BP [DBP]) in only a small percentage of the hypertensive population.1–3 Information on BP control in hospital-based hypertension units is scarce, yet the percentage of well-controlled patients (<140 mm Hg SBP and <90 mm Hg DBP) seems to be significantly higher in comparison with data obtained in primary care clinics.4–8
For some selected populations facing higher risk, especially for those with diabetes or renal disease, the Sixth Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-VI)9 and the World Health Organization–International Society of Hypertension (1999 WHO/ISH) guidelines10 established or suggested the adequacy of a goal BP <130/85 mm Hg. It was also suggested that treating a lower target BP (<130 SBP and <85 DBP) than that for most hypertensives (<140 SBP and <90 DBP) may be useful to prevent stroke, to prevent or slow heart failure progression, to alleviate persistent angina,9 or if there is compelling cardiovascular indication.11 Therefore, a lower BP goal may be indicated for groups of hypertensive patients in JNC-VI risk group C,9 as well as for patients stratified under the 1999 WHO/ISH guidelines as very high-risk or high-risk.10
Nevertheless, there are few reports that address BP control among these special subgroups of hypertensives by reference to their targeted BP. Furthermore, because the JNC-7 and 2003 European Society of Hypertension/European Society of Cardiology (ESH/ESC) guidelines have recently been released,12,13 and because they differ somewhat from JNC-VI and WHO/ISH guidelines, it may be of interest to consider the new, more aggressive goal BP <130/80 for those special populations (diabetes, renal disease). Finally, the behavior of physicians attending uncontrolled hypertensives has attracted recent attention14,15 and is perceived as a factor that may influence BP control in hospital-based hypertension units.
This is the first study in Spain to our knowledge to report on the degree of BP control achieved in hospital-based hypertension units across the whole nation in light of recommendations contained in international guidelines and that analyzes physician behavior toward patients with uncontrolled BP.
We performed a survey covering patients, aged 18 years or older, who had a diagnosis of essential hypertension, had been using antihypertensive therapy for ≥1 year, had been seen at 47 hospital-based hypertension units nationwide, and had been regularly followed-up by the same medical team in each unit.
All patients who met the inclusion criteria were included in the study only once during a 2-month period (May to June 2000) (n=4049). Patients with secondary hypertension and those who attended the first visit to the hospital unit on treatment prescribed by their family physicians were excluded.
Spanish hospital-based hypertension units are outpatient clinics located at hospitals that mostly belong to the National Health Service and tend to be the setting to which most patients are referred by primary care physicians in the event of difficult-to-manage hypertension. Such units are staffed by 2 to 4 physicians and 1 to 3 nurses trained as specialists in clinical hypertension. All patients were seen by the attending physician or nurse at each visit. No specific protocol was followed, but each physician was guided by the target of reducing BP in accordance with international guidelines.9–11 This study was approved in all cases by the Institutional Review Board at the participating hospitals, and informed consent was obtained from patients.
After a 5-minute rest, BP was determined in the seated position by a hospital-unit physician using appropriately sized cuffs and calibrated standard mercury sphygmomanometers. Korotkoff phases 1 and 5 were taken as SBP and DBP, respectively. Two measurements were performed at an interval of 5 minutes, with the mean of the 2 readings being deemed as defining the patient’s BP.
Additional data were collected from a structured questionnaire completed by the physician at the time of the study visit. This form contained items covering demographic data, accompanying cardiovascular risk factors, evidence of target organ damage, and previously diagnosed clinical cardiovascular disease (CCD) (myocardial infarction, angina, stroke, heart failure). Hypercholesterolemia was defined as total serum cholesterol >220 mg/dL or presence of current hypolipemic therapy. Obesity was defined as body mass index (BMI) ≥30 kg/m2, and overweight was defined as BMI 25 to 30 kg/m2. Diabetes mellitus was defined as fasting blood glucose repeatedly >126 mg/dL or current antidiabetic therapy. Microalbuminuria was defined as average urinary albumin excretion in two 24-hour periods of 30 to 300 mg daily, and proteinuria was defined as urinary protein excretion >300 mg daily (urine specimens obtained in most patients, determined by protocol). Left ventricular hypertrophy was defined as left ventricular mass index calculated from an M-mode echocardiogram (obtained in ≈50% of patients) >125 g/m2 or presence of electrocardiographic criteria (Sokoloff index >35 mm). Renal insufficiency was diagnosed when serum creatinine was >1.5 mg/dL in men and >1.4 mg/dL in women, or when proteinuria was present. Clinical parameters were defined and determined using standardized methods and conditions.9,10,16 Biochemical parameters corresponded to the last determination at the unit. Current use of different classes of drugs was likewise evaluated. In addition, physicians were asked whether they had prescribed a modification of hypertension treatment (and type of modification) for each patient after the visit (ie, after analysis of the BP reading taken at the visit).
Goal BP was defined as values <140/90 mm Hg for the general hypertensive population9,10,12,13 and <130/85 for special populations (diabetes, renal disease).9,10 We have also considered a goal BP <130/80 for hypertensives with diabetes or renal disease, according to the most recent guidelines,12,13 to describe how the data relate to this change in goal BP. Finally, BP control was also calculated for those patients stratified under the 1999 WHO/ISH guidelines as very high-risk or high-risk and medium/low-risk,10 as well as for patients in JNC-VI risk group C and risk groups A and B.9
Descriptive methods were used for analysis of all study variables. The relationships between BP control and other risk factors were analyzed using multiple logistic regression, with P<0.05 taken as statistical significance.
Baseline data for the 4049 hypertensives studied are shown in Table 1. Mean BP was 178±15/104±11 mm Hg when first seen at the units, and 144±20/85±10 mm Hg when estimated for the survey.
Selected Populations at Risk and Stratification by Risk
Patients with diabetes and patients with renal disease were characterized as being older, having higher BMI, higher SBP, and higher cardiovascular risk as compared with patients without diabetes and patients without renal disease, respectively (Table 2).
Applying the JNC-VI guidelines, 3011 patients (74.4%) were classified as belonging to risk group C. These patients were characterized by being older, having higher BMI, higher SBP, and higher cardiovascular risk as compared with risk groups A and B patients (Table 2). Similarly, according to the 1999 WHO/ISH criteria, 2539 (62.7%) patients had a high or very high risk. Age, BMI, SBP, and cardiovascular risk were higher in these patients than in those with a medium/low risk (Table 2).
BP Control and Drugs Used
At the date of the survey, BP values were <140 and 90 mm Hg in 1702 patients (42%). BP control in terms of the 140/90 mm Hg goal was achieved in 36.7% of patients with diabetes. However, only 13.2% reached the more stringent JNC-VI and 1999 WHO/ISH guideline goal (<130 SBP and <85 DBP), and only 10.5% achieved the even more rigorous JNC-7 and 2003 ESH/ESC guideline goal (<130 SBP and <80 DBP) (Table 3). These percentages were significantly lower than those in nondiabetic subjects. Among hypertensive patients with kidney disease, BP control <140 SBP and <90 DBP, <130 SBP and <85 DBP, and <130 SBP and <80 DBP (all mm Hg) was achieved in 35.5%, 17%, and 12.4%, respectively (Table 3). Again, these percentages were significantly lower than those in patients without kidney disease.
BP control <130 SBP and <85 DBP (mm Hg) was attained by 18.5% of patients with microalbuminuria. A total of 17% of patients with proteinuria of 30 to 1000 mg/d achieved a BP control <130 SBP and <85 (DBP) (mm Hg) (goal of JNC-VI). According to the JNC-7 and ESH/ESC guidelines, goal BP <130 SBP and <80 DBP (mm Hg) was achieved by 12% of patients with proteinuria >300 mg/d. Finally, for proteinuria >1 g/d, the BP goal is <125 SBP and <75 DBP (mm Hg) for all guidelines, and this BP value was attained by only 2.4% of these patients.
Regarding BP control among hypertensive patients stratified by total cardiovascular risk, a BP goal <130 SBP and <85 DBP (mm Hg) was attained by only 18% of patients in JNC-VI risk group C and 17% of WHO-ISH very high-risk and high-risk patients (Table 3). Both percentages were significantly lower than those in lower-risk groups (Table 3).
In all cases, ie, the total hypertensive population and the risk groups, BP control rates were significantly lower for SBP than for DBP (Table 4).
The univariate analysis showed that poorer BP control occurred in older patients, females, obese patients, diabetic patients, and in those treated with ≥2 antihypertensive drugs (Table 5). Interestingly, patients with diabetes or renal disease were using, on average, 2.3 antihypertensive medications versus 1.9 taken by those who had no diabetes/no renal disease (P<0.05). The percentage of hypertensive patients using diuretics, angiotensin-converting enzyme inhibitors (ACEIs) and calcium channel blockers (CCBs) was significantly higher in those with diabetes or renal disease (41%, 50%, and 52%, respectively) than in their nondiabetic/nonrenal disease counterparts (33%, 36%, and 38%, respectively). In the multivariate analysis, all variables, except for gender, remained statistically significant (P<0.05).
Concerning treatment, 34.6% of patients were using drug monotherapy, and 63.7% were using ≥2 drugs. Only 1.7% were treated without drugs but were strongly urged to adopt lifestyle changes. ACEIs, angiotensin II receptor antagonists (ARA II), and CCBs were the drugs most frequently prescribed on monotherapy (31.6%, 17.9%, and 17.0%, respectively), followed by β-blockers (10.4%), diuretics (4.9%), and α-blockers (4.4%). In combination, the drug associations most frequently prescribed were: ACEI plus CCB (9.4%); ACEI plus diuretic (7.9%); ACEI plus CCB plus diuretic (7.1%); ARA II plus CCB (5%); ARA II plus diuretic (4.6%); and ARA II plus CCB plus diuretic (3.1%). Diuretics was the therapeutic group most frequently used in combination (29.5%), followed by CCB (24.6%) and ACEI (22.2%).
Physicians’ Management With Regard to Uncontrolled Hypertension
Overall, physicians did not modify treatment in 51% of patients with a BP ≥140/90 mm Hg. These figure amounted to 58% and 57%, respectively, among diabetic patients or patients with kidney disease with a BP ≥130/85 mm Hg, and 60% and 62%, respectively, for patients with diabetes or kidney disease with a BP ≥130/80 mm Hg (Table 6). Likewise, these figures amounted to 62% and 61%, respectively, among JNC-VI risk group C patients and WHO-ISH high-risk patients with a BP ≥130/85 mm Hg (Table 6). Interestingly, these percentages of no drug treatment modification were higher in high-risk groups than in lower-risk groups. Finally, doctors who modified treatment did so mainly by adding another drug or, alternatively, by increasing the dose of the initially selected drug (Table 6).
Our data confirm that hypertensive patients followed-up in hospital hypertension clinics, especially those with diabetes or kidney disease or those in high-risk groups, exhibit an elevated level of cardiovascular risk linked to a high prevalence of target organ damage, CCD, diabetes, or other major CCD risk factors, a risk that is much higher than that observed for general populations.17 Hence, the hypertensive study population is characterized by the need for strict BP control.9,10
In accordance with other studies,5,6 we observed the percentage of patients attaining a BP level <140/90 mm Hg in hospital-based or specialized hypertension units to be significantly better than that obtained in population-based surveys1–3,18,19 or primary health care.7,8
Under the most recent guidelines on hypertension management,12,13 only 10% of diabetic patients and 12% of renal disease patients had their BP controlled. These figures are clearly lower than those corresponding to the <130 SBP and <85 DBP (mm Hg) goal of previous guidelines9,10 enforced at the time of the survey and accentuate further the need for better control in these selected populations. BP control (<125 SBP and <75 DBP mm Hg) is extremely low (2%) in those hypertensive patients with proteinuria >1 g/d.
Interestingly, despite the fact that BP control was rather similar between the US and European guideline high-risk (18% and 17%, respectively) and low-risk groups (46.1% and 46.4%, respectively), high-risk patients displayed lower BP control than did low-risk patients. This fact has also been observed in other studies,20 and the reason may be that high-risk patients tend to include the elderly and those with higher pretreatment BP who are inherently more difficult to control. This finding also evidences that those hypertensive patients who most needed their BPs to be controlled because they were at higher risk were precisely the ones most disadvantaged in terms of BP control. This is true even when high-risk and lower-risk groups are compared within the same BP goal. This also applies to those with diabetes or renal disease, whose BP control is lower than that in nondiabetic/nonrenal disease patients.
Predictors of BP control have been investigated in various studies, and the presence of target organ damage, CCD, and diabetes invariably figure among the best predictors of poor BP control,4,5,21 findings that were replicated in our study. These high-risk groups impose the need to attain a lower goal (<130 SBP and <80 to 85 DBP mm Hg) in accordance with the guidelines,9–13 which in turn leads to the percentage of good control decreasing significantly to as low as ≈20%, and lower still among diabetic patients. Different reasons may underlie this finding.
First, attainment of such a low goal BP, especially of SBP, is difficult with available drugs, particularly in patients with these characteristics. In fact, two-thirds of our patients were being treated with combinations including ≥2 drugs. Although the percentage of hypertensive patients using diuretics, alone (1.7%) or in combination (29.5%), was only less than the percentage using ACEI (33.1%), diuretics (mostly of thiazide-type) were the antihypertensive group most frequently used in combination.
Second, Spanish physicians attached to hospital hypertension units are disinclined to adopt more aggressive therapeutic management to improve BP control in many uncontrolled BP patients. Indeed, these physicians introduced therapeutic modifications in less than half of the patients with inadequate BP control (as low as 38% among high-risk patients). Interestingly, this reluctance to modify treatment was more marked among individuals in high-risk groups or with diabetes or renal disease (as high as 60% to 62%) than in lower-risk groups (52% to 59%). That is, clinical inertia was higher in groups of uncontrolled hypertensives that needed to have their treatment modified more than did other patients. These figures of drug treatment modification, although higher than those seen in general practice,15 are unexpectedly low at hospital-based hypertension clinics. Although almost half of all treatment modification consisted of introducing a drug association, a single-drug strategy was nevertheless maintained by doctors in ≈30% of uncontrolled hypertensives. However, not only does more aggressive behavior on the part of doctors treating uncontrolled hypertension seems feasible but also would it serve to improve BP control, particularly in cases in which the patient’s age is advanced.14,15,22 As expected, we also found BP control to be lower as more antihypertensive drugs were required to attain BP control,15 especially for the SBP target. In fact, diabetic patients, who were the hypertensives with more uncontrolled BP, were those who were using, on average, more antihypertensive medications. As expected, the percentage of patients with diabetes or renal disease using ACEI was significantly higher than that for patients without diabetes or renal disease.
Third, more effective implementation of physicians’ knowledge concerning the need to control BP at goal levels in the majority of patients seen at hospital units is probably required. Although we lack data to confirm this possibility, it nevertheless seems reasonable to assume that enhanced knowledge will contribute to improved BP control. Finally, it is also possible that the guideline recommendations may be unrealistic, at least in the case of high-risk patients. In this regard, no study to our knowledge has yet been undertaken in which this question has been answered.
In summary, hospital-based hypertension units follow-up a population of hypertensive patients characterized by very high cardiovascular risk. Consequently, intervention must be integrated and include control of many different factors. Among these, strict control of BP, and SBP in particular, is the goal that, according to our data, still needs to be clearly improved. In particular, patients at high risk for CCD, with diabetes, renal disease, proteinuria, or obesity, warrant focused attention. Moreover, to improve BP control, more aggressive behavior on the part of doctors treating uncontrolled hypertension would seem to be called for, especially for those at higher risk.
Investigators on Behalf of the CLUE Study
Fernández Andrade Carlos, Hospital Virgen del Rocío, Sevilla, Spain; Villar Ortiz José, Hospital Virgen del Rocío, Sevilla, Spain; Mediavilla García Juan Diego, Hospital Virgen de las Nieves, Granada, Spain; Fernández Torres Celia, Hospital Virgen de las Nieves, Granada, Spain; Castellanos Guerrero Victoriano, Hospital Comarcal de la Serranía, Ronda, Spain; Grilo Reina Antonio, Hospital U. Ntra. Sra. de Valme, Sevilla, Spain; Oliván Martínez Josefina, Hospital Virgen de la Macarena, Sevilla, Spain; Rodríguez Martínez Manuel Ángel, Hospital De la Inmaculada, Huercal-Overa, Spain; Gil Extremera Blas, Hospital Clínico San Cecilio, Granada, Spain; Maldonado Antonia, Hospital Clínico San Cecilio, Granada, Spain; Martín Salguero Antonio, Hospital Clínico San Cecilio, Granada, Spain; Liébana Cañada Antonio, Hospital Ciudad de Jaén, Jaén, Spain; Aranda Lara Pedro, Hospital Regional Carlos Haya, Málaga, Spain; Laviades Álvarez Concepción, Hospital San Jorge, Huesca, Spain; Virto Ruiz Rafael, Hospital San Jorge, Huesca, Spain; Logroño González José Manuel, Hospital San Jorge, Huesca, Spain; Tisaire Sánchez Javier, Fundación FIHA, Zaragoza, Spain; Cía Gómez Pedro, Hospital Clínico de Zaragoza, Zaragoza, Spain; Marín Iranzo Rafael, Hospital Ntra. Sra. Covadonga, Oviedo, Spain; Fernández Vega Francisco, Hospital Ntra. Sra. Covadonga, Oviedo, Spain; Gorostidi Pérez Manuel, Hospital De Jarrio, Jarrio, Spain; Herrera Pérez del Villar Julio, Hospital Central de Asturias, Oviedo, Spain; Rodríguez Pérez José Carlos, Hospital Dr. Negrin, Las Palmas de Gran Canaria, Spain; Maceira Cruz Benito, Hospital Univ. La Laguna, Tenerife, Spain; Hawari Meilud Adnan; Hospital Ntra. Sra. de los Reyes, El Hierro, Spain; Sanz de Castro Saturnino, Hospital Marqués de Valdecilla, Santander, Spain; Tornero Molina Fernando, Hospital Virgen de la Luz, Cuenca, Spain; Sánchez Heras Marta, Hospital Guadalajara, Guadalajara, Spain; Jarillo Ibáñez Dolores, Hospital Guadalajara, Guadalajara, Spain; Martín García Jesús, Hospital Ntra. Sra. De Sonsoles, Ávila, Spain; Palencia García Ángel, Hospital Clínico Univ. De Valladolid, Valladolid, Spain; Suliman Jabary Najaty, Hospital Clínico Univ. De Valladolid, Valladolid, Spain; Herruzo Gallego José, Hospital Clínico Univ. De Valladolid, Valladolid, Spain; Salvá Llompart María, Hospital Río Carrión, Palencia, Spain; Monfá Bosch José María, Hospital Río Carrión, Palencia, Spain; Ocón Pujades Juan, Fundación Puigvert, Barcelona, Spain; Oliveras i Serrano Anna, Hospital Del Mar, Barcelona, Spain; Romero Ramón, Hospital Germans Trias i Pujol, Barcelona, Spain; Armario Pedro, Hospital Cruz Roja, Barcelona, Spain; Hernández del Rey Raquel, Hospital Cruz Roja, Barcelona, Spain; Coca Antonio, Hospital Clínico de Barcelona, Barcelona, Spain; De la Sierrra Alejandro, Hospital Clínico de Barcelona, Barcelona, Spain; Roca i Cusach Alejandro, Hospital Santa Creu y Sant Pau, Barcelona, Spain; Tovar Méndez José Luis, Hospital Valle de Hebrón, Barcelona, Spain; Planas Jaume, Fundación Estudio y Tratamiento de la HTA, Barcelona, Spain; Sobrino Javier, Fundación Estudio y Tratamiento de la HTA, Barcelona, Spain; Redon i Mas José, Hospital Clínico de Valencia, Valencia, Spain; Robles Nicolas Roberto, Hospital Infanta Cristina, Badajoz, Spain; Martínez Debén Francisco, Hospital Arquitecto Marcide, La Coruña, Spain; Lorenzo Aguiar Dolores, Hospital Juan Canalejo, La Coruña, Spain; Otero González Alfonso, Hospital Cristal-Piñor, Orense, Spain; Ruilope Luis Miguel, Hospital Doce de Octubre, Madrid, Spain; Campo Carlos, Hospital Doce de Octubre, Madrid, Spain; Segura Julián, Hospital Doce de Octubre, Madrid, Spain; García Robles Rafael, Hospital Ramón y Cajal, Madrid, Spain; Suárez Carmen, Hospital La Princesa, Madrid, Spain; Torre Carballada Alberto, Hospital Univ. La Paz, Madrid, Spain; Martell Nieves, Hospital Clínico San Carlos, Madrid, Spain; Luque Otero Manuel, Hospital Clínico San Carlos, Madrid, Spain; Fernández Pinilla MŞ Carmen, Hospital Clínico San Carlos, Madrid, Spain; López Vidriero Emilio, Hospital Gregorio Marañón, Madrid, Spain; Abellán Alemán José, Centro de Salud San Andrés, Murcia, Spain; Martínez Fernández Isabel, Hospital De Galdácano, Galdácano, Spain; Morán Jesús Manuel, Hospital De Cruces, Baracaldo, Spain; Muñiz Martín Ricardo, Hospital De Cruces, Baracaldo, Spain.
Main funding for the study was obtained from Bristol-Myers Squibb through an unrestricted educational grant. The funding body had no role in the collection, analyses, or interpretation of data, or in the decision to submit the paper for publication.
- Received January 15, 2004.
- Revision received February 5, 2004.
- Accepted March 26, 2004.
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