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Diagnostic Evaluation of the Hypertensive Patient- How much is enough?. Thomas Pickering MD, DPhil Behavioral Cardiovascular Health and Hypertension Program Columbia Presbyterian Medical Center New York.
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Diagnostic Evaluation of the Hypertensive Patient- How much is enough? Thomas Pickering MD, DPhil Behavioral Cardiovascular Health and Hypertension Program Columbia Presbyterian Medical Center New York
Diagnostic Evaluation of the Hypertensive Patient- How much is enough? How high is the blood pressure? Why is it high? What is the risk?
Diagnostic Evaluation of the Hypertensive Patient- How much is enough? How high is the blood pressure? How should it be measured?
How should the Blood Pressure be Measured? • In the Clinic • By the doctor? • By a nurse? • By an automated device? • Outside the Clinic • Home monitoring? • Ambulatory monitoring?
60 60 50 50 40 40 30 30 20 20 Clinic 24-hr 10 10 Daytime Nighttime 0 0 190 110 130 190 150 110 170 130 150 170 Ambulatory BP and Cardiovascular Disease in the Elderly with Systolic Hypertension: The Syst-Eur Study (N = 808) High risk group- Clinic BP underestimates risk Placebo Active treatment Cardiovascular disease (per 1000 patient - year) Low risk group- WCH Clinic BP overestimates risk Staessen et al. JAMA 1999; 282: 539-46.
The White Coat Effect in the Real World(Little et al, BMJ 2002; 325: 254) 173 hypertensive patients in 3 general practices in the UK Clinic (MD and RN), self-monitoring, and ABPM White coat effect estimated as difference between other measures of BP and daytime BP:- Physician 19/11 mmHg Nurse 1 5/8 mmHg Nurse 2 5/6 mmHg Self-monitoring in clinic 10/13 mmHg Self-monitoring at home 5/6 mmHg
Clinic Pressure White Coat Hypertension Sustained Hypertension 140/90 True Normotension Masked Hypertension 135/85 Ambulatory Pressure
A Diagnosis of Hypertension based exclusively on Physician readings is no longer acceptable • Measurement error • Small number of readings • Effects of recent activities • Expense & Inconvenience • White coat effect
Prospective Studies Showing that Home BP Predicts CV Morbidity Better than Clinic BP Author Year Population N Comments Imai 1996 Population 1789 ABP & HBP predict, not CBP Bobrie 2004 Treated 4939 HBP predicts, not CBP Sega 2005 Population 2051 HBP predicts better than CBP
Prospective Studies Showing that Home BP Predicts CV Morbidity Better than Clinic BP Author Year Population N Comments Imai 1996 Population 1789 ABP & HBP predict, not CBP Bobrie 2004 Treated 4939 HBP predicts, not CBP Sega 2005 Population 2051 HBP predicts better than CBP Home monitoring should be recommended for all patients
Call to Action for the Reimbursement of Home BP Monitoring Supported by American Heart Association American Society of Hypertension Preventive Cardiovascular Nurses Association
Which measure of Blood Pressure should we worry about most? • Systolic? • Diastolic? • Pulse?
Change of Blood Pressure with Age (NHANES- Black Women) Systolic Blood Pressure mm Hg Diastolic Age
Relations Between SBP, DBP and Stroke in Different Age Groups (Prospective Studies Collaboration Lancet 2002; 360: 9349)
Relations Between SBP, DBP and Stroke in Different Age Groups (Prospective Studies Collaboration Lancet 2002; 360: 9349) Even at ages 80-89 DBP risk
CHD Deaths Versus SBP And DBP In MRFIT CHD Deaths Per 1000 Pt-Years Diastolic Pressure (mm Hg) Systolic Pressure (mm Hg) Neaton et al. Arch Intern Med. 1992;152;56.
CHD Deaths Versus SBP And DBP In MRFIT CHD Deaths Per 1000 Pt-Years Diastolic Pressure (mm Hg) Systolic Pressure (mm Hg) Neaton et al. Arch Intern Med. 1992;152;56.
Diagnostic Evaluation of the Hypertensive Patient- How much is enough? How high is the blood pressure? Why is it high? What is the risk?
JNC 7: Identifiable Causes of Hypertension • Sleep apnea • Drug-induced or related causes • Chronic kidney disease • Primary aldosteronism • Renovascular disease • Chronic steroid therapy and Cushing’s syndrome • Pheochromocytoma • Coarctation of the aorta • Thyroid or parathyroid disease
JNC 7 Recommendations for Routine Work-up of Hypertensive Patients • Routine Tests • Electrocardiogram • Urinalysis • Blood glucose, and hematocrit • Serum potassium, creatinine, or the corresponding estimated GFR, and calcium • Lipid profile, after 9- to 12-hour fast, that includes high-density and low-density lipoprotein cholesterol, and triglycerides • Optional tests • Measurement of urinary albumin excretion or albumin/creatinine ratio • More extensive testing for identifiable causes is not generally indicated unless BP control is not achieved
Dyslipidemia and the risk of Hypertension (Halperin et al Hypertens 2006: 47:45) • 3110 men followed for 14 years in Physicians’ Health Study • Baseline lipids analyzed by quintiles LDL Chol HTN Risk by 39% Tot Chol HTN Risk by 23% Baseline HDL Chol HTN Risk by 32%
Antihypertensive Effect of Pravastatin in Patients with Hypertension and Hypercholesterolemia (Glorioso et al; Hypertens 1999: 34:1281) Systolic pressure mmHg Placebo Placebo Placebo Statin Statin Placebo LDL cholesterol mmol/l 0 4 8 12 16 20 24 28 32 36 40 Weeks
ASCOT: Main Results (Blood Pressure-Lowering Arm: BPLA & Lipid-Lowering Arm: LLA) Effects of intervention on events Endpoint BPLA* LLA** Blood Pressure Lipids Primary 10%- NS 36% Death 11% 13%- NS Stroke 23% 27% Total events/ 16% 21% procedures * BPLA- ACEI/CCB vs. BB/Diuretic ** LLA- Statin vs. placebo
Cardiovascular Risk Factors in “Prehypertension” (TROPHY) None -4% Three or more- 59% One- 14% Two- 22% (Nesbitt et al, AJH 2005;18:980)
Cardiovascular Risk Factors in “Prehypertension” (TROPHY) None -4% Three or more- 59% Cholesterol >200 HDL <40 TG >150 BMI > 25 Glucose >110 Insulin >20 Heart rate >80 Hematocrit >43 or 41 One- 14% Two- 22% (Nesbitt et al, AJH 2005;18:980)
Overlap of Four Common Conditions Obesity Hypertension Diabetes Sleep Disordered Breathing
Overlap of Four Common Conditions Obesity Metabolic Syndrome Hypertension Diabetes Sleep Disordered Breathing
Association Between SDB and Hypertension- SHHS Parent Study(Nieto et al, JAMA 2000;283,1829) Adjusted for BMI etc. Not adjusted for BMI Odds Ratio of HTN Apnea-Hypopnea Index per Hour
Sleep Disordered Breathing Predicts Hypertension- the Wisconsin Study(Peppard et al, NEJM 2000; 342: 1378) Odds Ratio for Hypertension* Apnea-Hypopnea Index *Adjusted for baseline BP, BMI, age etc.
No Relationship between Isolated Systolic Hypertension & Sleep Apnea: SHHS Study(Haas, Pickering et al, Circ 2005) P<0.002 Odds Ratio for HTN NS <1.5 1.5-5 5-15 15-30 >30 AHI
Prevalence of SDB in Hypertension % 50 SHT 40 % of SDB AHI > 15/hr 30 WCHT 20 High MHT NT 10 Clinic BP 140/90 mmHg 0 Low High Low Awake ABP 135/85 mmHg
Abnormalities Associated with the Metabolic Syndrome Central Obesity Hypertension Non-dipping pattern of 24 hr BP Salt sensitive Dyslipidemia High triglycerides Low HDL cholesterol Increased small dense LDL Insulin resistance Type II diabetes Increased NEFAs Endothelial dysfunction Increased PAI-I Increased platelet aggregation Microalbuminuria Obstructive Sleep apnea
High Prevalence of Sleep Apnea in Resistant Hypertension (Logan et al J Hypertens 2001:19:2271) • 41 consecutive patients with 3 drug-resistant hypertension evaluated with PSG and ABPM • Clinic BP was 168/94 on 3.6 drugs; most were obese • 83% had OSA (AHI >10); commoner in men (96%) than women (65%) • ABPM showed that 64% were non-dippers; no difference in dipping between those with and without OSA
Situations in which Renin/Aldosterone Measurement May Be Helpful • Suspected secondary hypertension, e.g. hypokalemia (measure off drugs) • Refractory hypertension (measure on drugs) • Intolerance to multiple drugs (measure off drugs)
Diagnostic Evaluation of the Hypertensive Patient- How much is enough? How high is the blood pressure? Why is it high? What is the risk?
JNC 7: CVD Risk Factors • Hypertension* • Cigarette smoking • Obesity* (BMI >30 kg/m2) • Physical inactivity • Dyslipidemia* • Diabetes mellitus* • Microalbuminuria or estimated GFR <60 ml/min • Age (older than 55 for men, 65 for women) • Family history of premature CVD (men under age 55 or women under age 65) *Components of the metabolic syndrome.
JNC 7: Target Organ Damage • Heart • Left ventricular hypertrophy • Angina or prior myocardial infarction • Prior coronary revascularization • Heart failure • Brain • Stroke or transient ischemic attack • Chronic kidney disease • Peripheral arterial disease • Retinopathy
Why Is Echocardiography Useful In Hypertensive Patients? “No other biological variable (except advancing age) predicts cardiac risk better than left ventricular hypertrophy”. (De Simone et al, J Hypertens 12;1129, 1994)
How Common is LVH in Hypertensive Patients? ECG LVH in about 5% of ht patients Echo LVH in 15-30% of unselected ht patients Echo LVH in 20 to 60% of ht patients in referral centers
Indications for Echocardiography in Hypertensive Patients • Coexistent Heart Disease • Resistant Hypertension • Decision to Start Treatment Uncertain
Echocardiographic LVMI as a Predictor of CV Risk (Schillaci et al, Hypertens 2000; 35: 580) CV Events per 100-pt years Quintiles of LVMI
Microalbuminuria Category Spot collection 24 hour mg/mg creatinine mg/24 hr Normal <30* <30 Microalbuminuria 30-300 30-300 Albuminuria >300 >300 Normal levels a bit lower in men (25 vs 35)
Microalbuminuria Relation to other CV Risk Factors • Hypertension • Hyperlipidemia • Central obesity • Smoking • LVH • Coronary Disease • Non-dipping BP pattern
Urine Albumin Predicts CV and Non-CV Mortality in the General Population (Hillege et al Circ 2002; 106: 1777) Cardiovascular Hazard Ratio for Death Non-cardiovascular Urinary Albumin (mg/L)
Microalbuminuria and CHD risk in Hypertension (Borch-Johnsen et al ATVB 1999;19:1992) Relative risk of CHD High Urine albumin Low <140 140-160 >160 Systolic Pressure
Effects of Enalapril and Nitrendipine on Urine Albumin (Bianchi et al AJH 1991; 4:291) Nitrendipine Urine albumin (mg/24 hr) Enalapril Weeks
Diagnostic Evaluation of the Hypertensive Patient- How much is enough? • In all patients • Sleep history • BMI • Out-of-office Blood Pressures (home monitoring) • Microalbuminuria
Diagnostic Evaluation of the Hypertensive Patient- How much is enough? • In selected patients • Plasma renin/aldosterone • Out-of-office Blood Pressures (ambulatory monitoring) • Echocardiogram
National Heart, Lung, andBlood Institute National High Blood PressureEducation Program Seventh Report of the Joint National Committee onPrevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) EXPRESS