Hemodynamic versus specialist hypertension management: results of a randomized trial

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O-7 PROGNOSTIC IMPACT OF AMBULATORY BLOOD PRESSURE CONTROL IN TREATED HYPERTENSIVE PATIENTS Paolo Verdecchia, Giuseppe Schillaci, Gianpaolo Reboldi, Giuseppe Ambrosio, Carlo Porcellati. 1University of Perugia, Perugia, Italy, 2 Silvestrini Hospital, Perugia, Italy Office blood pressure (BP) is not adequately controlled in many treated hypertensive patients. Prevalence and prognostic impact of ambulatory BP control are largely unknown. In the setting of a prospective cohort study in hypertensive patients (PIUMA study), we evaluated the prognostic impact of office and ambulatory BP control in 759 patients with essential hypertension. Clinical data, including office and 24-hour ambulatory BP, were obtained before treatment and after an average of 3.6 years. Treatment was tailored to the single patient. At the follow-up visit, 27% of patients had adequate office BP control (⬍ 140/90 mmHg) and 39% had adequate 24-hour ambulatory BP control (⬍ 130/80 mmHg). During a follow-up period of up to 14 years, 55 patients experienced a first major cardiovascular event. Event rate did not differ significantly between patients with adequate or inadequate office BP control at the previous visit (0.97 vs 1.63 events x 100 patient-years; p ⫽ 0.24). In contrast, when BP control was assessed on the basis of 24-hour ambulatory BP, event rate was lower in well than in poorly controlled patients (0.90 vs 1.88 events x 100 patient-years; p ⫽ 0.02). After adjustment for age (p⫽0.002), diabetes (p⫽0.0003), and left ventricular hypertrophy (p⫽0.007), 24-ambulatory BP control was associated with a 60% lesser risk for subsequent cardiovascular disease (95% confidence intervals: 19-81%; p⫽0.011). These findings indicate for the first time that ambulatory BP control is superior to office BP control for cardiovascular risk stratification in treated hypertensive patients. Key Words: Ambulatory Blood Pressure, Prognosis, Left Ventricular Hypertrophy

O-8 HOW WELL DOES A SPECIALIST CLINIC COMPARE TO MANAGED CARE ORGANIZATIONS FOR HYPERTENSION CONTROL? Gregory M. Singer, Unini Odama, Jason C. Robin, Henry R. Black, the Rush University Hypertension Service. 1Preventive Medicine, Rush Presbyterian-St.Luke’s Medical Center, Chicago, IL, United States The control of hypertension has recently been added to the Health Plan Employer Data Information Set (HEDIS) Measures for 2000. The degree of blood pressure control for patients 46 - 85 years of age who have an established diagnosis of hypertension and have been enrolled in the plan for at least 12 months is estimated using the last recorded office blood pressure. For all patients, except those patients with end-stage renal disease, goal blood pressure is ⬍140/90 mm Hg. A sitting blood pressure is used if available. If not, the supine value is used, with standing BP used only if no other values are available. We evaluated the percent of those who reached the HEDIS goal to estimate the prevalence of controlled hypertension in a tertiary care hypertension clinic. The Rush University Hypertension Service is comprised of 4 physicians, 3 of whom are certified Clinical Hypertension Specialists. Most of the patients were referred for refractory hypertension. No specific clinical pathway was used and no drug regimen was manadated. All patients seen at the Rush University Hypertension Service from September, 1998 to February, 2000 were evaluated based on HEDIS criteria (N⫽588) of which 428 fulfilled the criteria and were evaluated for blood pressure control. Of the 160 patients excluded, 44% were excluded due to age, 12% lacked a diagnosis of hypertension and 36% had not been enrolled in the clinic for at least one year. Charts were unavailable for review in 8% of the patients. © 2001 by the American Journal of Hypertension, Ltd. Published by Elsevier Science Inc.

ORALS: Clinical Significance of Blood Pressure Monitoring Methods

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The eligible cohort was 50% male; mean age was 64 ⫾ 11 years. The mean systolic BP was 138 mmHg ⫾ 14 and mean diastolic BP was 79 mmHg ⫾ 8 after at least one year in clinic. Goal BP (⬍140/90 mm Hg) was achieved in 65% of these patients. An additional 27% reached only diastolic control below 90 mmHg with 8% having only SBP ⬍140 mm Hg. Single drug therapy was used in 28%, with 34%, 21.3%, 11.6%, 4.4% requiring 2, 3, 4 or ⬎5 medications respectively to achieve goal BP. The regimens included calcium antagonists in 59%, diuretics in 57%, angiotensin converting enzyme inhibitors in 39%, beta-blockers in 23%, alpha-blockers in 22%, and angiotensin receptor blocker in 15%. These data compare favorably to the average BP control rate of 39 ⫾10% seen in a survey of 257 Managed Care Organizations. Despite beginning with a cohort of patients referred for refractory hypertension, hypertension specialists were able to nearly double the proportion of patients reaching blood pressure goal. Multi-drug therapy was necessary in an overwhelming majority of the patients. Grant/Research: BMS, Pharmacia, Pfizer, MSD, HMR Consultant: Pharmacia, Astra-Merck, BMS Speakers’ Bureau: BMS, Pfizer, MSD, HMR, Astra-Merck, WyethAyerst Key Words: Hypertension control, specialist clinic, Health Employer Data Information Set

O-9 HEMODYNAMIC VERSUS SPECIALIST HYPERTENSION MANAGEMENT: RESULTS OF A RANDOMIZED TRIAL Sandra J. Taler, Stephen C. Textor, Jo E. Augustine, John C. Burnett. 1 Hypertension and Internal Medicine, Mayo Clinic, Rochester, MN, United States Resistant hypertension (RH) (⬎140/90 mm Hg despite multiple drugs) continues to pose a challenge despite improved drugs. To examine the role of non-invasive hemodynamic (HD) measurements (thoracic bioimpedance), we randomized 103 RH subjects to a 3-month trial of either HD directed drug Rx or clinical Rx by a hypertension specialist (SC) blinded to HD. Pre-randomization BP Rx averaged 3.6⫾0.1 drugs/pt, including diuretics (91%), ACE inhibitors/ARBs (81%) and CCBs (59%). HD measurements included cardiac index (CI), peripheral resistance (SVRI), and thoracic impedance reflecting central thoracic fluid volume (TBI). Protocol drugs were selected based upon HD values by pre-determined algorithm. Subjects returned monthly for drug and dose titration. Mean age was 66⫾1 yrs. Cardiovascular risk was high with multiple comorbidities (33% diabetic, 50% hyperlipidemic). Results were as follows: Hemodynamic Treatment Entry Final

Specialist Care Entry Final

Systolic BP (mm Hg) 169 ⫾ 3 139 ⫾ 2**## 173 ⫾ 3 147 ⫾ 2** Diastolic BP (mm Hg) 87 ⫾ 2 72 ⫾ 1**## 91 ⫾ 2 79 ⫾ 1** Serum creat (mg/dL) 1.3 ⫾ 0.1 1.6 ⫾ 0.1** 1.3⫾ 0.1 1.5 ⫾ 0.1* -5 -2 SVRI (d-sec-cm -m ) 3309 ⫾ 112 2794 ⫾ 86**# 3354 ⫾ 96 3067 ⫾ 87** Supine TBI (ohms) 33.4 ⫾ 1.1 36.0 ⫾ 1.0** 34.4 ⫾ 1.1 36.8 ⫾ 1.2** Mean⫾SEM *p⬍0.05 vs entry, **p⬍0.01 vs entry, #p⬍0.05 vs SC, ##p⬍0.01 vs SC

HD protocol subjects reached goal BP (ⱕ140/90 mm Hg) more often (56% vs 34%, p⬍0.05). HD measurements demonstrated elevated SVRI and central fluid volume in RH, despite previous Rx. Final drug numbers were similar, but daily diuretic doses were higher in HD (3.3⫾0.4 vs 2.3⫾0.3 dose equivalents, p⬍0.05). Cardiac index remained stable with medication adjustments. SVRI was elevated at study entry, with greater reduction achieved in the HD patients correlating with lower BP readings. TBI rose with treatment as did serum creatinine reflecting reduction in central volume, independent of change in weight. These data indicate 0895-7061/01/$20.00

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ORALS: Clinical Significance of Blood Pressure Monitoring Methods

that non-invasive HD management achieved superior BP levels and control rates, when compared to management by experienced hypertension clinicians. Our results suggest that sequential non-invasive HD provide effective guidance in drug selection and titration in treatment resistant hypertensives. Key Words: Drug therapy, Resistant hypertension, Hemodynamics

O-10 HOME BLOOD PRESSURE: ARE WE MEASURING THE TRUE BLOOD PRESSURE? Kiyohito Okumiya, Fumiyasu Yamasaki, Takashi Furuno, Kyoko Sato, Kozo Matsubayashi, Toshio Ozawa, Tetsuro Sugiura, Yoshinori Doi. 1 Medicine & Geriatrics , Japan,2Clinical Laboratory, Kochi Medical School Kochi, Japan,3The Center for Southeast Asian Studies, Kyoto University Kyoto, Japan,4Tokyo Metropolitan Geriatric Hospital Tokyo, Japan Home blood pressure measurement is a casual and appropriate method to evaluate blood pressure (BP) without white coat effect. However, little is known about the BP measurement effect on BP during early period of the measurement. To evaluate the effect of BP measurement and age on home blood pressure, 1156 community-dwelling residents free of antihypertensive drugs, aged 35-93 years (499 men and 657 women), participated twice a day home BP measurement for two weeks. Subjects were divided into middle-aged (aged⬍65, n⫽624) and the elderly (agedⱖ65, n⫽532) age groups. Results showed that the morning systolic BP in the elderly group tended to show higher value during the first 4 days of measurement compared to later period of measurement. On the other hand, those in the middle-aged group had no significant difference during the 2 weeks. There was no significant difference in the evening systolic BP during the 2 weeks, which was lower than the morning systolic BP in both groups. In conclusion, BP measurement itself affects the home BP at least for 4 days in the elderly people.

Key Words: home blood pressure, measurement effect, age

O-11 ACCURACY OF HOME AND OFFICE BLOOD PRESSURE MONITORS ARE THE MEASUREMENTS THE SAME? Steven A. Yarows. 1 Hypertension, University of Michigan Health System, Chelsea, MI, United States Purpose: Oscillometric blood pressure (BP) measurement measures the mean BP and calculates through proprietary software systolic (SBP) and diastolic (DBP) BP. Do the different proprietary methods result in differences in measured readings between monitors and how do the monitors function in clinical usage? Methods: BP measurement comparisons were performed with a variety of home BP monitors (HBPM) using two methods with each with a minimum of 85 measurments: an artificial BP simulator (SIM) and normotensive subjects compared to a single home BP monitor (HUMAN). Comparisons were also performed between different HBPM that were purchased by patients and calibrated with a single measurement via SIM using a standard pressure (PM) and waveform methods (WM).

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Results: The absolute differences between models of different manufacturers using SIM and repetitive measurements was 12/9mmHg with a pulse difference of 3 beats/minute (BPM). The difference using HUMAN was 4/7mmHg with the pulse difference of 2BPM. The SBP measured by HBPM was equivalent to mercury (average difference 0.18mmHg), however HBPM under-estimated DBP by an average of 8.25mmHg. Only 4 home aneroid manometers were calibrated from patients with a 3.3-19mmHg difference in pressures measured from the standard. Ninty-six oscillometric patient machines were calibrated using SIM via the PM (n⫽57) and WM (n⫽39). The absolute difference for all of the models with the PM was 3-4mmHg, with the exception of the Lumiscope model that had a 16.6 difference at 90mmHg. The absolute difference using the WM was 7.3-13.9mmHg for SBP and 5.8-8.0mmHg for DBP and 2.1 BPM for pulse. Conclusion: The proprietary algorithm used to calculate SBP and DBP result in differences between the machines. The absolute differences are usually within the ⫹/-5mmHg accuracy suggested by AAMI for static pressures, although some individual models are outside this accuracy. The absolute differences also approximate the human variation in measurement seen in non-research clinical settings. The pulse differences between monitors is slight, as expected due to standard measurement techniques between manufacturers. Consultant: OMRON HEALTHCARE, Inc. Key Words: accuracy of measurement, home blood pressure monitoring, blood pressure measurement

O-12 AMBULATORY BLOOD PRESSURE MONITORING: IS IT NECESSARY IN THE ROUTINE ASSESSMENT OF HYPERTENSION IN DIABETIC PATIENTS? Mark W.J. Strachan, Kathleen Gough, John A. McKnight, Paul L. Padfield. 1Medical Sciences, Western General Hospital, Edinburgh, United Kingdom Hypertension is common in association with diabetes mellitus and recent studies have confirmed the primacy of BP control in reducing cardiovascular morbidity in this high risk group of patients. The British Hypertension Society (BHS) has recently published revised guidelines on the management of hypertension which include a target clinic BP of ⬍ 140/80 mm Hg in the diabetic population. The target for daytime or awake ABPM was set at ⬍ 130/75 mm Hg. Such targets are arbitrary but have the potential to influence large numbers of doctors within the UK and we have assessed how they might be used and interpreted in diabetic patients. Between 1997 and 1999, ABPM was performed 582 times on 542 patients referred from the diabetic clinic at our hospital for evaluation of clinic hypertension. Patients were aged 24 to 85 years (54% male) and comprised a mixture of treated and non-treated patients. Spacelabs monitors were fitted to the non-dominant arm by a trained nurse. The second BP measurement (recorded by the monitor after at least 5 min rest) was checked against a mercury manometer using a two-way tap and was taken as the clinic BP.The monitor was worn for 24 hours with recordings made at 30 min intervals throughout. Awake and sleep periods were defined according to patient diaries. There is evidence to suggest that an absence of a nocturnal fall in BP might increase cardiovascular risk so we identified the proportion of non-dippers using the conventional criterion of a nocturnal BP fall of ⬍ 10%. We examined the number of times a carefully obtained clinic BP would be above the BHS target but the ABPM would be below target implying that treatment was unnecessary or adequate. 342 patients had a clinic BP ⬎140/80 and only 6 of these had an awake ABP ⬍ 130/75. Of 93 who had clinic systolic or 73 with clinic diastolic hypertension only 7 and 3 respectively were ⬍130/75 on ABP. On 508 (87%) occasions both the clinic and awake ABPM were both above the BHS target implying that ABPM added nothing to the decision making process. Disparity occurred only in only 3% of patients. Non-dipping was