2007 Hypertension as a Public Health Risk January, 2007

2007

Hypertensionas a Public

Health Risk

January, 2007

2007 Canadian Hypertension Education Program Recommendations2

Proportion of deaths attributable to leading risk factors worldwide (2000)

Ezzati et al. WHO 2000 Report. Lancet. 2002;360:1347-1360.

Attributable Mortality (In millions; total 55,861,000)

High mortality, developing regionLower mortality, developing regionDeveloped region

0 87654321

High blood pressure

Tobacco

High cholesterol

Unsafe sex

High BMI

Physical inactivity

Alcohol

Indoor smoke from solid fuels

Iron deficiency

Underweight


Hypertension is a significant risk factor for:– cerebrovascular disease– coronary artery disease– congestive heart failure– renal failure– peripheral vascular disease– dementia– atrial fibrillation

Hypertension as a Risk Factor


Adapted from : Third National Health and Nutrition. Examination Survey, Hypertension 1995;25:305-13

30-39 40-49 50-59 60-69 70-79 80

70

80

110

130

150

Age

30-39 40-49 50-59 60-69 70-79 80

70

80

110

130

150

Age

Men Women

PPPP

Blood Pressure Distribution in the Population According to Age

PP=Pulse Pressure.


Classification of Hypertension

Category Systolic DiastolicOptimal <120 and / or <80Normal <130 and / or <85High-Normal 130-139 and / or 85-89Grade 1 (mild hypertension ) 140-159 and / or 90-99Grade 2 (moderate hypertension) 160-179 and / or 100-109Grade 3 (severe hypertension) 180 and / or 110Isolated Systolic Hypertension (ISH)

140 and / or <90

The category pertains to the highest risk blood pressure

*ISH=International Society of Hypertension. Chalmers J et al. J Hypertens 1999;17:151-85.

(Pre Hypertension) 120-139 / 80-89


Blood Pressure and Risk of Stroke Mortality

Lancet 2002;360: 1903-13


Blood Pressure and Risk of IHD Mortality

Lancet 2002;360: 1903-13


CAD Death Rate per 10,000 Person-years

100+ 90-99 80-89 75-79 70-74 <70<120

120-139

140-159

160+

Diastolic BP (mmHg)

Systolic BP (mmHg)

20.610.3 11.8 8.8 8.5 9.2

11.812.612.813.9

24.6 25.3 25.2 24.9

16.923.8

31.025.8

34.743.8

38.1

80.6

37.448.3

Neaton et al. Arch Intern Med 1992; 152:56-64.

Effect of SBP and DBP onAge-Adjusted CAD Mortality: MRFIT


Impact of High-Normal Blood Pressure on the Risk of Cardiovascular Disease

N Engl J Med 2001;345:1291-7

CUMULATIVE INCIDENCE OF CV EVENTS IN MEN WITHOUT HYPERTENSION ACCORDING TO BASELINE BLOOD PRESSURE

(130-139)

(121-129)

(< 120)

mmHg


The Concept of Masked Hypertension

From Pickering, Hypertension 1992

Office SBP mmHg

Ambu

lato

ry S

BP m

mHg

Truehypertensive

TrueNormotensive White Coat HTN

Masked HTN

White Coat HTNTrueNormotensive

Masked HTNTruehypertensive

200

180

160

140

120

100100 120 140 160 180 200

135


The Prognosis of Masked HypertensionPrevalence is approximately 10% in hypertensive patients.

05

101520253035

Normal23/685

White coat24/656

Uncontrolled41/462

Masked236/3125

Bobrie et al. JAMA 2004;291:1342-9

CV

eve

nts

per 1

000

patie

nt-y

ear CV Events


Cumulative hazard for stroke in 3 groups of subjects: Normotensive, White-Coat Hypertension, and Ambulatory

hypertension

Verdecchia, P et al. Short- and Long-Term Incidence of Stroke in White-Coat Hypertension. Hypertension. 45(2):203-208, February 2005.

Time to stroke (years)

0 1 2 3 1615141312114 105 6 7 8 9

Cum

ulat

ive

haza

rd o

f str

oke

(%)

0

1

2

3

4

5

6

7

8White-coat hypertension

p = 0.0013

Normotensivegroup

Ambulatoryhypertension


Benefits of Treating Hypertension

• Younger than 60– reduces the risk of stroke by 42%– reduces the risk of coronary event by 14%

• Older than 60– reduces overall mortality by 20% – reduces cardiovascular mortality by 33%– reduces incidence of stroke by 40%– reduces coronary artery disease by 15%


Correlation Between Reduction in SBP and Stroke or MI

Staessen et al. Lancet 2001;358:1305-15.

Stroke Myocardial Infarction


Correlation Between Reduction in SBP and Cardiovascular Mortality or Events

Cardiovascular mortality Cardiovascular events

Staessen et al. Lancet 2001;358:1305-15.


Benefits of Treating to Target

• Older than 60 with isolated systolic hypertension(SBP 160 mm Hg and DBP <90 mm Hg)

– 36% reduction in the risk of stroke– 25% reduction in the risk of coronary events

Ref: adapted from SHEP, SYST-EUR, STONE studies.


Effect of Long-Term Modest Reductions in CV Risk Factors

Emberson et al. Eur Heart J. 2004;25:484-491.

10% Reduction

in BP

10% Reductionin Total-C+

45% Reduction

in CVD=


Evaluating the Impact of Different Strategies for CV Prevention on CV Risk Reduction.

Treating hypertension and other risk factors.

Adapted from Emberson et al. Eur Heart J. 2004;25:484-491.

Pred

icte

d R

educ

tion

in

Maj

or C

VD (%

)

Treatment Based on TC

(statin)

Treatment Based on BP(β-blocker,

diuretic)

Treatment Based on Overall Absolute Risk

(ASA, statin, ACEI, β-blocker, diuretic)

-6 -6

-17

-9 -8

-28

-12-10

-37-40

-35

-30

-25

-20

-15

-10

-5

0

Top 10%

Top 20%

Top 30%

Treatment thresholds


22% of Canadians 18-70 years of age have hypertension50% of Canadians >65 years of age have hypertension

Joffres et al. Am J Hyper 2001;14:1099 –1105

21%13%

43%22%

Hypertensive patients who are treated

but BP uncontrolled

Hypertensive patientswho are treated

and BP controlled

Hypertensive patients who are unaware

Patients who are awarebut remain untreatedand BP uncontrolled

9%

Diabetic patientswho are treated and

BP controlled

The Challenge In Canada


Results of a survey on awareness on hypertension (Canada 2002)

67% of aware hypertensive patients believe that their BP was their own primary responsibility

Two thirds of these patients stated that high BP was not a serious concern.

Thus the mandate to improve public awareness of the consequences of hypertension is clear.

R. Petrella MD, Perspective in Cardiology, March 2002.


The Canadian Hypertension Education Program Objectives

• Develop evidence-based recommendations for the management of hypertension

• Implement recommendations• Evaluate impact of the program


Leading diagnoses resulting in visits to physician offices in Canada

Mill

ion

visi

ts/y

ear

0

5

10

15

20

25

Hyp

erte

nsio

n

Dep

ress

ion

Dep

ress

ion

Dia

bete

sD

iabe

tes

Rou

tine

med

ical

R

outin

e m

edic

al

exam

sex

ams

Acu

te re

spira

tory

Acu

te re

spira

tory

trac

t inf

ectio

ntr

act i

nfec

tion

Source: IMS HEALTH Canada 2002. http://www.imshealthcanada.com/


Changes in diagnosis of hypertension in Canada

Post 1999 compared to pre 1999

• Doubling of the rate of diagnosis of hypertension

• Closing of the gender gap

Hypertension 2006;48:853-60

Hypertension Diagnosis by Gender

10

15

20

1992 1994 1996 1998 2000 2002 2004

Year

Perc

enta

ge o

f Pop

ulat

ion

Females

Males &FemalesMales


Changes in the treatment of hypertension


• Doubling of the rate of treatment of hypertension

• Closing of the gender gap


Hypertension Treatrment by Gender

5

10

15

20

1992 1994 1996 1998 2000 2002 2004

Year

Perc

entage

of P

opulation

Females

Males & Females

Males


Changes in the proportion of thosediagnosed that are not treated


• Marked decrease in proportion of aware hypertensives that are untreated

• Closing of the gender gap.


Hypertensives who were Aware but not treated by Gender

10

20

30

40

1992 1994 1996 1998 2000 2002 2004

Year

Perc

entage

of P

opulation

Females

Males &FemalesMales


2007 Canadian Recommendations for the Management of Hypertension

A slide kit for medical education can be downloaded from:

http://www.hypertension.ca

Documents

2007 Hypertension as a Public Health Risk January, 2007