# Presentation: 709609

## Epidemiologic and Clinical Significance of Incremental  Changes in Blood Pressure

**William B. Kannel, MD, FACC**
**Professor of Medicine and Public Health****Boston University School of Medicine**
**Former Director, Framingham Heart Study**

## Hypertension Is a Major Treatable Risk Factor for Cardiovascular Disease 

**Powerful independent risk factor for CHD, stroke, PAD, and heart failure**
**Relationship with risk is continuous ****and graded**
**Benefits of blood pressure reduction with pharmacologic treatment are incremental ****and continuous**

**CHD = Coronary heart disease.**
**PAD = Peripheral arterial disease.**

## Coronary Heart Disease Risk by Major Risk Factors 

**5**

**	****Elevated ****	****Hypertension****	****Diabetes****	****Smoking****	**** cholesterol**

**Framingham Study—36-yr Follow-up **

**Risk ratio****	**
**35-64 yr****	****1.9******	****1.8*****	****2.0******	****2.2******	****1.5******	****3.7******	****1.5******	****1.1**
**65-94 yr****	****1.2****	****2.0******	****1.6******	****1.9******	****1.6*****	****2.1******	****1.0****	****1.2**

********p***** < 0.01; *******p***** < 0.001. Kannel WB. Framingham Heart Study.**

## Risk for Cardiovascular Events by Diastolic Blood Pressure

**Framingham Study **
**Patients aged 35 to 64 yr, initially free of CVD; 38-yr follow-up**

**Kannel WB. Framingham Heart Study.**

## Risk for Cardiovascular Events by Systolic Blood Pressure

**Framingham Study **
**Patients aged 35 to 64 yr, initially free of CVD; 38-yr follow-up**

**Kannel WB. Framingham Heart Study.**

## Relative Risks of Stroke and Coronary Heart Disease† 

**4.00**

**2.00**

**1.00**

**0.50**

**0.25**

**76**

**84**

**91**

**98**

**105**

**4.00**

**2.00**

**1.00**

**0.50**

**0.25**

**76**

**84**

**91**

**98**

**105**

**Relative risk of stroke**

**Relative risk of CHD**

**Stroke**

**CHD**

**7 prospective****observational studies:**
**843 events**

**9 prospective****observational studies:**
**4,856 events**

**Approximate mean usual DBP, mm Hg**

**†****420,000 patients for CHD, 405,500 patients for stroke, 10-yr mean follow-up period. MacMahon et al. *****Lancet*****. 1990;335;765-774.**

**5**

## Reducing Diastolic Blood Pressure Lowers Coronary Heart Disease and Stroke Risk† 

**†****420,000 patients for CHD, 405,500 patients for stroke, 843 strokes, 4,856 CHD events, **
**10-yr mean follow-up period.**
**MacMahon S, et al. *****Lancet*****. 1990;335:765-774.**

**5**

## Incremental Reduction in Diastolic Blood Pressure Lowers Coronary Heart Disease and Stroke Risk

**†****Data from MacMahon S, et al. *****Lancet*****. 1990;335:765-774.**
**††****Adapted from Hebert PR, et al. *****Arch Intern Med*****. 1993;153:578-581.**
**†††****Estimated risk reduction.**

**Observational studies,****†**** mm Hg**

**Drug treatment trials,****††**** mm Hg**

**–****2**

**–****5 to –6**

**–****7.5**

**–****2****†††**

**–****5 to –6**

**–****7.5****†††**

## Advantage of Additional BP Reduction: NNTT to Prevent 1 Stroke Event†

**NNTT = Number needed to treat.**
**†****Men aged 60 to 69 yr. **
**††****Smoker, SBP 150 mm Hg, CVD, HDL < 40 mg/dL, cholesterol > 260 mg/dL.**
**Kannel WB. Framingham Heart Study.**

**	****	****	****Framingham average****Reduction in DBP****	****NNTT****	****risk/10 yr**
**5 - 6 mm Hg****	****Average risk****	****28****	****38%****	****High risk****††****	****15****	****46%**
**7.5 mm Hg****	****Average risk****	****20****	****38%****	****High risk****††****	****  9****	****46%**

## Reduction in Systolic Blood Pressure Lowers Coronary Heart Disease and Stroke Risks

**†****SHEP. *****JAMA*****. 1991;265:3255-3264. ****††Staessen JA, et al. *****Lancet*****. 1997;350:757-764.**

**	****SHEP****†****	****Syst-Eur****††**
**Baseline BP, mm Hg****	****170/77****	****184/85**
**BP reduction, mm Hg****	****11/3****	****10/4-5**

## US Adults With HypertensionUnmet Medical Need

**NHANES III (Phase 2) 1991-1994 (JNC VI). Estimated 50 million adults with hypertension in the US.**
**†****Percent = Proportions based on persons with hypertension in the survey.**
**††****BP < 140/90 mm Hg.**

**Aware**

**Treated**

**Controlled****††**

**Percent****†**

## Physician PracticesTreating Hypertension 

**Hypertension, particularly ISH, seldom treated to recommended goal**
**No increase in medication at 75% of visits despite continued BP elevation**
**Drugs rarely up-titrated; reluctance to include additional drugs**
**Therefore, more effective monotherapy drugs could facilitate attaining recommended treatment goals**

**ISH = Isolated systolic hypertension.**
**Coppola WG, et al. *****J Hum Hypertens*****. 1997;11:185-191.**
**Berlowitz DR, et al. *****N Engl J Med*****. 1998;339:1957-1963.**

## Conclusions: Importance of Incremental Blood Pressure Reduction

**Hypertension is a major treatable risk factor for CVD including CHD, stroke, PAD, and heart failure**
**Incremental blood pressure reduction is meaningful from a public health perspective**
**Benefits of blood pressure reduction with pharmacologic treatment are incremental ****and continuous**
**Compelling need for clinicians to use the more effective BP-reducing drugs to achieve recommended treatment goals in individual patients**