HYPERTENSIONRelation Between Hypertension and Obesity

Mohammad Ilyas, M.D.

Assistant Clinical Professor

University of Florida / Health Sciences Center

Jacksonville, Florida USA6/24/2014

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Outline

1. Definition, Regulation and Pathophysiology

2. Measurement of Blood Pressure, Staging of Hypertension and Ambulatory

Blood Pressure Monitoring

3. Evaluation of Primary Versus Secondary

4. Sequel of Hypertension and Hypertension Emergencies

5. Management of Hypertension (Non-Pharmacology versus Drug Therapy)

6. The Relation Between Hypertension: Obesity, Drugs, Stress and Sleep

Disorders.

7. Hypertension in Renal diseases and Pregnancies

8. Pediatric, Neonatal and Genetic Hypertension

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Obesity

Definition: excessive weight that may impair health

How do we measure If someone is obese?

Body mass index (BMI) – the weight in kilograms divided by the square of the height in meters (kg/m2)

BMI Categories:

Underweight BMI < 18.5

Normal weight = 18.5-24.9

Overweight = 25-29.9

Obesity = BMI of 30 or greater

Morbid Obesity = BMI > 40

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Just the Facts! As of 2008 WHO

Globally, More than 1.4 billion adults are overweight

More than half a billion obese (>500,000,000)

2.8 million people each year die as a result of being overweight

or obese.

40 million preschool children were overweight

overweight and obesity kills more people than underweight

Projects by 2015, 2.3 billion will be overweight and 700 million

obese

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Childhood Obesity

Rates of childhood obesity are alarming

Problem is worldwide

Estimated in 2010, 42 million children

under age 5 are considered overweight

Tripled in past 30 years

Age 6-11 6.5% to 19.6%

Age 12-19 5.0% to 18.1%

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Childhood Obesity

Genetic Link

Multi-factorial condition related to sedentary lifestyle,

too much food intake and choice of

foods actually alter genetic make-up, creating higher risk

of obesity

Behavioral

Children will more likely choose healthier foods

if they are offered to them at young ages and

in the home

Environment

In homes where healthy food is not available, or the food

choices are not healthy, obesity can occur 6/24/2014

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Childhood Obesity

Why does this matter?

Premature death

Developing heart disease at younger ages

Developing diabetes type 2 at younger ages

What can be done?

Childhood obesity is preventable

Role of the schools

Role of health care professionals 6/24/2014

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Cause of Obesity

Simple equation…when you eat more than

you use, it is stored in your body as “fat”.

Causes

Global shift in how we eat

Western diet of processed food

Higher sugar, fat and calories in what we eat

Less nutrients

Reduced intake of vitamins and minerals 6/24/2014

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What does obesity do to our bodies?

With more people gaining too much weight..there

are health issues to consider

Cardiovascular disease

Diabetes type 2

Musculoskeletal disorders

Cancers-endometrial, cervical and colon

Infertility

Gallstones

Premature death and disability

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Heart Disease and Diabetes

Heart Disease

The world’s number #1 cause of death

Kills 17 million each year around the world

Heart attack

Stroke

Diabetes type 2

Becoming global epidemic

WHO projects diabetes will increase by 50% across the

world

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Hypertension

Weight gain raises blood pressure

Obesity further enhances total cardiovascular risk and all-

cause mortality

Excess body weight accounted for approximately 26 percent

of cases of hypertension in men and 28 percent in women

Approximately 23 percent of cases of coronary heart disease

in men and 15 percent in women

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BMI (>/= 25kg/m2)

Essential hypertension

78%-in male

65%-in female

(Vasant RS, Larson MG et al, 2001)

Dolls, Bovet P et al, 2002

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Body mass index and the risk of disease

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Adult weight change and the risk of disease

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PATHOGENESIS OF HYPERTENSION

Initially, an elevation in cardiac output and a relatively normal

systemic vascular resistance (SVR).

Later, obese subjects is an elevation in SVR in hypertensive.

Increased activation of the renin-angiotensin aldosterone system.

These hemodynamic alterations plus abnormalities in lipid and

glucose metabolism appear to be related to fat distribution as

well as to total body weight.

In particular, the risk is greatest in those patients with abdominal

obesity, which is a major component of the metabolic syndrome.

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Hyperinsulinemia and Hypertension

The mechanism by which obesity raises the BP is not well

understood.

A variety of mechanisms have been proposed to explain how

hyperinsulinemia might increase BP

Increased sympathetic activity

Volume expansion due to increased renal sodium reabsorption

Endothelial dysfunction

Up regulation of angiotensin II receptors, and

Decreased cardiac natriuretic peptide .

Genetic susceptibility

Despite these observations, the role of insulin resistance or hyperinsulinemia as a cause of hypertension remains unproven

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Sleep apnea syndrome

The sleep apnea syndrome is an additional contributing

factor to the development of hypertension in obese

patients.

Activation of the sympathetic nervous system,

Enhanced aldosterone levels, and

Increased levels of endothelin by repeated episodes of hypoxia

are thought to be responsible in part for the elevation in

blood pressure in this disorder

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Leptin-melanocortin pathway

The correlation between the serum concentration of leptin, a

protein that signals the brain about the quantity of stored fat,

and body fat content

With increasing adiposity, leptin acts as a negative feedback

"adipostatic" signal to brain centers controlling energy intake

The melanocortin receptor, which is expressed on downstream

targets of leptin and insulin responsive-neurons, is involved in

the regulation of energy balance and may also modulate blood

pressure

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Leptin pathway in hypertension development in obesity

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Weight reduction

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EFFECTS OF WEIGHT REDUCTION

Weight loss may lead to a significant fall in systemic BP.

A mean fall in blood pressure of 6.3/3.4 mmHg with weight loss diets.

Weight reducing drugs, particularly orlistat, can also reduce blood

pressure,

Weight loss surgery (eg, Roux-en-Y gastric bypass), in addition to lifestyle

interventions, also reduces blood pressure,

The fall in blood pressure with weight loss is accompanied by a decrease

in arterial stiffness

The decline in BP induced by weight loss can also occur in the absence of

dietary sodium restriction; however, modest sodium restriction (a

decline in intake of 20 to 40 meq/day) may produce an additive

antihypertensive effect

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EFFECTS OF WEIGHT REDUCTION

Calorie expenditure > Calorie intake by 10%

Net 3500 kcal energy burning gives 0.45 kg body fat loss.

A meta analysis by staessen et al. showed that mean SBP & DBP reductions were 1.6/1.1 mmHg per kg of body weight by aerobic program.

18 month weight loss program associated with 77% reduction in incidence of hypertension.

(He J, Whelton PK et al.2000)

The exact mechanism by which weight reduction lowers blood pressure is not known.

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Resistance Training

Strength exercise can even be used for lowering blood pressure.

The actual blood pressure response depends on:

• isometric component

• exercise intensity

• Muscle mass activated

• number of repetitions

• duration of contraction

• involvement of valsalva maneuver

Bjarnason – Wehrens B, Mayer – Berger W et al, 20046/24/2014

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However, a need exists for additional well designed studies on this

topic before a recommendation can be made regarding the efficacy

of resistance exercise as a non pharmacologic therapy for reducing

the resting blood pressure in hypertensive individuals.

Kelley G et al, 1997

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Isometric Exercise

Isometric exercise such as weight lifting can have a pressor

effect and therefore should be avoided. Thus it is strictly

contraindicated.

(Krousel Wood MA, Muntner P et al, 2004)

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Long-term effects of weight reduction

The persistence of weight loss provides substantial benefits

Sustained weight loss of 6.8 kg or more was associated with a 22 -

26 % reduction in relative risk of developing hypertension

Weight loss of 10 to 20 percent was associated with a reduction in

total and resting energy expenditure

Increase in physical activity should always be added to diet

Markedly obese patients may require surgical therapy to produce

and maintain an adequate degree of weight loss.

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SUMMARY AND RECOMMENDATIONS

Obesity is an important risk factor for hypertension and all-cause

mortality.

Weight loss can lead to a significant fall in blood pressure.

Antihypertensive agents will often be necessary if adequate

weight loss cannot be achieved or sustained.

Angiotensin converting enzyme inhibitors, angiotensin receptor

blockers, or dihydropyridine calcium channel blockers may be the

antihypertensive agents of choice.

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Hypertension: Personality Traits

Upset by criticism

Upset by imperfection

Pent up anger, bitterness

Low self-confidence

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Stress and Anxiety Control

Meditation was in one study to reduce SBP and DBP by 10.7 mm Hg and 6.4 mm Hg over a period of 3 months

Schneider RH Alexander CN et al, 1995

Progressive muscle relaxation lower SBP by 4.7 mm Hg and DBP by 3.3mm Hg.

Yoga is also widely believed to reduce blood pressure

Damodaran A, Patil N, Suryavanshi et al, 2002

However, these interventions are with limited and uncertain efficacy. Therefore more trials are needed to confirm its effect.

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Conclusion

Hypertension is a silent killer.

Cardiopulmonary Physiotherapy is an integral part of

health service.

Evidence supports that exercise is the cornerstone for

hypertension control, then why it is not being utilized.

This is the time, physiotherapist must emerge and show

their potential to beat paramount disorder like

hypertension where even pharmacological management

fails.

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