Note on Hypertension

1. Chairperson:
Dr. Nagaraj Patil
Lecturer,
Dept of Public Health
JNMC, Belagavi
Presented By:
Dr. Spurthi S M
Vijaya C J
MPH Sem II
Dept. of Public Health
JNMC , Belagavi

2. Contents
• Introduction
• Definition
• Classification
• Measurement
• Epidemiology
• Treatment
• Prevention
• Summary

3. Introduction
 Definition of Blood Pressure:
Blood pressure is the force exerted by circu
lating blood against the walls of the body’s
arteries, the major blood vessels in the bo
dy. Hypertension is when blood pressure is
too high.
 Blood pressure is written as two number
s. The first (systolic) number represents t
he pressure in blood vessels when the h
eart contracts or beats. The second (dias
tolic) number represents the pressure in
the vessels when the heart rests between
beats.

4. Definition
Definitions of Hypertension
 abnormally high blood pressure and especially arterial blood pr
essure
 the systemic condition accompanying high blood pressure
(Merriam-Webseter dictionary)
Systematic arterial hypertension is defined as a state of chronical
ly elevated arterial blood pressure, as compared to what is nor
mally expected.
(AFMC text book )
 Hypertension is diagnosed if, when it is measured on two differ
ent days, the systolic blood pressure readings on both days is
≥140 mmHg and/or the diastolic blood pressure readings on b
oth days is ≥90 mmHg.
(WHO)

5. Pathophysiology

6. CLASSIFICATION
Hypertension can be classified in 3 different ways
 According to the level of blood pressure
 According to identifiable cause, if any
 According to the extent of target organ
damage

7. According to Level of BP
Source: JNC 7 classification
https://www.aanpcert.org/newsitem?id=94

8. According to Level of BP
Blood Pressure Category SBP DBP
Normal <120 mm Hg and <80 mm Hg
Elevated 120-129 mm Hg and <80 mm Hg
Hypertension
Stage 1 130-139 mm Hg or 80-89 mm Hg
Stage 2 >140 mm Hg or >90 mm Hg
Hypertension Crisis >180 mm Hg and/or >120 mm Hg
Hypertensive crisis: Systolic over 180 and/or diastolic over 120, with patients
needing prompt changes in medication if there are no other indications of
problems, or immediate hospitalization if there are signs of organ damage.
Here BP indicates blood pressure (based on an average of ≥2 careful readin
gs obtained on ≥2 occasions); DBP, diastolic blood pressure; and SBP systolic
blood pressure.
Source: American Heart Association 2017
https://www.ahajournals.org/doi/full/10.1161/HYP.0000000000000066

9. According to Level of BP
Isolated systolic hypertension
Systolic blood pressure of 140 mm of Hg or
more and
a diastolic blood pressure of less than 90 mm
of Hg.

10. Classification in Pediatrics
 For children aged 1-13 years:
 Normal BP: < 90th percentile
 Elevated BP: > 90th percentile to <95th percentile or
120/80mmHg to <95th percentile (whichever is lower
)
 Stage 1 HTN: > 95th percentile to <95th percentile +
12mmHg, or 130/80 to 139/89 mmHg (whichever is
lower)
 Stage 2 HTN: > 95th percentile + 12 mmHg, or
> 140/90 mmHg (whichever is lower)

11. For children aged > 13 years
 Normal BP: <120/<80 mmHg
 Elevated BP: 120/<80 to 129/<80 mmHg
 Stage 1 HTN: 130/80 to 139/89 mmHg
 Stage 2 HTN: > 140/90 mmHg
( Source: American Academy of Pediatrics)

12. According to identifiable cause, if any
 Primary (essential) :Hypertension th
at does not have any identifiable ca
use(idiopathic)
 Secondary: Hypertension have som
e identifiable cause for raised BP.
 Malignant hypertension: It is extre
mely high blood pressure that devel
ops rapidly and causes some type of
organ damage. (180/120 mmHg).

13. According to the extent of target organ
damage
Heart : IHD, LVH, Heart Failure
Brain : Stroke, TIA
Chronic kidney disease
Peripheral arterial disease
Retinopathy

14. Measuring Blood Pressure
 The first BP meter was invented by Samuel Siegfried Karl Ritter v
on Basch in the year 1881.
 Further improvised by when Nikolai Korotkov in 1905 by includi
ng diastolic blood pressure measurement following his discovery
of "Korotkoff sounds.“
 In 1981 the first fully automated oscillometric blood pressure cuff
was invented by Donald Nunn.
SPHYGMOMANOMETER
sphygmo + manometer.
Sphygmo Manometer
Pulse Pressure Meter

15. Sphygmomanometer
Types of SPHYGMOMANOMETER :
Manual Hybrid/Digital

16. Sphygmomanometer
Aneroid Sphygmomanometer
When mounted to the wall
they are called Baumanometer

17. Sphygmomanometer

18. Contd..
Children (by age) Cuff Size
Newborns and premature infants 4X8 cm
Infants 6X12 cm
Older children 9X18 cm

19. Guidelines for measuring BP
WHO recommendation
 Sitting position should be adopted for recording blood pressure.
 In any clinic a uniform policy should be adopted, using either the rig
ht or left arm consistently.
 The pressure at which the sounds are first heard (phase I) is taken to
indicate the systolic pressure.
 Near the diastolic pressure the sounds first become muffled (phase I
V) and then disappear (phase V).
 The systolic and diastolic pressures should be measured at least thre
e times over a period of at least 3 minutes and the lowest reading re
corded.
 For reasons of comparability, the data should be recorded everywher
e in a uniform way.

20. Contd..
Sources of errors :
 Observer errors- hearing acuity, interpretation of Korotkoff soun
ds.
 Instrumental errors- leaking valve, cuffs that do not encircle the
arm. If the cuff is too small and fails to encircle the arm properl
y then too high a reading will be obtained;
 Subject errors- the circumstances of examination. These include
the physical environment, the position of the subject, external s
timuli such as fear, anxiety etc.

21. “Tracking” of blood pressure
If blood pressure levels of individual
s were followed up over a period of
years from early childhood into adu
lt life, then those individuals whose
pressures were initially high in the
distribution, would probably contin
ue in the same “track” as adults.

22. How is Hypertension A
Public Health Problem

24. Rule Of Halves
1. The whole community
2. Normotensive subjects
3. Hypertensive subjects
4. Undiagnosed hypertension
5. Diagnosed hypertension
6. Diagnosed but untreated
7. Diagnosed and treated
8. Inadequately treated
9. Adequately treated
96
7
8
5
4
3
1
2

25. Incidence
 Concept of incidence has limited value
 Variability of consecutive readings in individuals, ambiguity of
what is normal blood pressure and the insidious nature of the
condition.
 Worldwide, causes 7.5 million deaths, about 12.8% of the total
of all deaths.

26. Global prevalence
Adults aged 25 years - 40 per cent in 2008.
The prevalence in high-income countries was lower, at 35% for b
oth sexes.
Across the WHO regions, the prevalence of raised blood pressur
e was highest in Africa, where it was 46% for both sexes combine
d.
Across the income groups of countries, the prevalence of raised
blood pressure was consistently high, with low, lower-middle and
upper-middle income countries all having rates of around 40% for
both sexes.

27. Global Prevalence
Source: AHA Journal 2013

28. Contd..

29. Contd…
 The prevalence of hypertension varies across the WHO regions
and country income groups. The WHO African Region has the
highest prevalence of hypertension (27%) while the WHO Regi
on of the Americas has the lowest prevalence of hypertension
(18%).
 A review of current trends shows that the number of adults wi
th hypertension increased from 594 million in 1975 to 1.13 bill
ion in 2015, with the increase seen largely in low- and middle-
income countries. This increase is due mainly to a rise in hype
rtension risk factors in those populations.

30. Prevalence (Region-wise)

31. Prevalence in INDIA
Source:https://www.acc.org 2015

32. Prevalence in INDIA

33. Risk Factors

34. Management Of Hypertension

35. Management Of Hypertension

36. PREVENTION OF HYPERTENSION
The WHO has recommended the following approaches in the preven
tion of hypertension:
Primary prevention
All measures taken to reduce the incidence of disease in a popula
tion by reducing the risk of onset.
A. Population strategy
 Directed at the population.
 Based on the fact even a small reduction in the average blood pressur
e population would produce a large reduction in the incidence of cardi
ovascular complications such as stroke and CHD.

37. Primary Prevention
Population strategy
This involves a multifactorial approach, based on the following non-phar
macotherapeutic interventions:
 Nutrition :
reduction of salt in take to an average of not more than 5 gm per day
moderate fat intake
 Weight reduction: dietary changes.
 Exercise promotion , yoga
 Behavioral changes: Reduction of stress and smoking, alcohol intake
modification of personal life style.
 Health education
 Self care

38. Primary Prevention
High-risk strategy
 Aim of this approach is “to prevent the attainment o
f levels of blood pressure at which the institution of
treatment would be considered”
 This approach is appropriate if the risk factors occur
with very low prevalence in the community.

39. Secondary Prevention
Goal of secondary prevention is to detect and control
high blood pressure in affected individuals.
Uses the following approaches
1. Early case detection
2. Treatment
3. Patient compliance

40. Schematic Representation

41. Tertiary Prevention
 The role of Doctors as well as paramedical persons a
ssumes importance in context of tertiary prevention
 To follow up the patient, to advocate continuous tre
atment, to educate the patients about importance of
treatment and the various precautions to be taken
by them.

42. Summary
Hypertension is defined as a state of chronically eleva
ted arterial blood pressure, as compared to what is nor
mally expected.
Hypertension is classified according to the level of blo
od pressure, identifiable cause and extent of organ da
mage.
Blood pressure is measured by Sphygmomanometer.
Prevention of control of Hypertension through
primary, secondary and tertiary prevention.

43. References
 K. Park Preventive and social medicine;banarsidas bhanot 23rd E
dition; page no-372-377.
 Text book of public health and community medicine;AFMC 1st E
dition; page no-1213-1217.
 Davidsons principles and practices of medicine; elsevier 20th Edi
tion; page no- 606-615.
 https://www.heart.org
 https://www.aha journals.org
 https://www.acc.org/latest-in-cardiology/articles/2017/11/08/11/
47/mon-5pm-bp-guideline-aha-2017
 https://en.wikipedia.org/wiki/Sphygmomanometer