What effect does obesity have on high blood pressure
Obesity is defined as the abnormal accumulation of body fat. It is diagnosed by measuring the weight and height of an individual, thereby determining the body mass index (BMI>30kg/m2). This condition enhances the risk of development of hypertension. Men and women with a body mass index (<30 kg/m2) have a 5 times higher chance of developing high blood pressure than persons with a body mass index less than 20 kg/m2.
The Framingham study estimates that obesity may be responsible for 26% cases of hypertension in men and 28% in women.
Excess body weight primarily results from an imbalance between energy intake and energy expenditure. The factors predisposing to this condition include
- Excess energy intake
- Calorie-dense, nutrient-poor food choices (e.g., sugar-sweetened beverages)
- Low physical activity
- Sedentary lifestyle
- Little or excess sleep
- Certain diseases (e.g., Cushing's syndrome)
- Psychological conditions (e.g., depression, stress)
- Specific drugs (e.g., steroids)
This condition is a significant factor that predisposes to high blood pressure. The following pathologic mechanism leads to the development of high blood pressure in obese individuals.
Adipocyte (fat cell) is not merely an organ for storage of energy, but it also secretes factors that may result in elevated blood pressure.
Obesity-induced hypertension has no apparent signs and symptoms. The related health problems include increased sweating, difficulty breathing, tiredness, inability to cope up with everyday activities, joint pains, vision changes, irregular heartbeat, and angina-like chest pain.
High blood pressure and obesity increase the risk of type 2 diabetes, stroke, chronic kidney disease, heart disease, peripheral vascular disease, and death.
Excess body weight is diagnosed by assessing the body mass index (BMI), waist circumference, and waist-to-hip ratio.
Body mass index (BMI)
Body mass index is a simple and commonly used measure for categorizing obesity. It is obtained by dividing the weight of the individual in kilograms with the square of the height in meters (kg/m2). According to the World Health Organisation criteria, an individual is considered obese if the BMI>30kg/m2.
Waist circumference and waist: hip ratio
Waist circumference a measure of abdominal adiposity is measured from the midpoint of the inferior border of rib cage and the iliac crest. Waist: hip ratio provides a useful index of abdominal fat accumulation than BMI alone.
High blood pressure is established if the blood pressure is consistently higher than 140/90 mm Hg.
The following are the list of medications used for treating hypertension in obese individuals. This includes
- Angiotensin-converting enzyme inhibitors (Captopril, lisinopril, enalapril, Ramipril)
- Β-blockers (Atenolol, Metoprolol, propranolol)
- Calcium channel blocker (verapamil, diltiazem, nifedipine)
- Diuretics (furosemide, bumetanide, Ethacrynic acid, Chlorthalidone)
These drugs when used at high doses are efficient for managing obese hypertensive individuals.
Treatment approach primarily requires managing the excess body weight. This requires lifestyle changes aimed at reducing body weight, thereby consuming a low-calorie diet of 500 – 1,500 or 500 – 1,200 calories for men or women, correspondingly.
It also includes restricted salt intake with lower intake of saturated fats, increased consumption of water, fruits, raw vegetables, fish, lean meats, whole grain, moderate continuous physical activity and adequate sleep.
These eating patterns and physical activities strengthen the muscular mass while decreasing the fat content.
- Excess weight apart from raising the blood pressure interferes with the efficiency of hypertensive drugs.
- Weight loss helps decrease blood pressure
- For each kg of weight lost, diastolic and systolic blood pressure reduces by 2 mmHg.
- Therefore weight loss is the cornerstone in the management of the obesity-hypertension syndrome.
- This might be achieved with diet, exercise, medications, and a combination of these measures.