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Showing posts with label obesity. Show all posts
Showing posts with label obesity. Show all posts

How will you diagnose obesity clinically ?

Overweight is defined as when the body weight is 10% excess over the upper limit of standard weight in relation to age and sex of that individual.
Obesity is defined as when the body weight is 20% more than the upper limit of standard weight in relation to age and sex of that individual.

How will you clinically diagnosis obesity?
1) Body weight > 20% above the ideal body weight or BM1 >30.
2) When measured by a special calliper, a fat fold thickness of greater than one inch in the inferiorangle of scapula in  (male) or the midtriceps region in (female) is called as obesity.
3) Ponderal index < 12 is obesity

How to diagnose obesity based on BMI?
BMI (a measure of generalised obesity) is obtained by calculating a person's weight in kilograms and dividing it by the person’s height in metres squared (kg/m2)
BMI in adults Range
Acceptable range   18.5 -24.9
Overweight        25.0 -29.9
Obese               30.0 -39.9
Morbidly obese    > 40

Waist hip ratio
According to the recent evidence the regional distribution of fat may be of greater prognostic significance than the absolute degree of obesity. Abdominal or truncal obesity can be clinically measured bv ‘waist-hip ratio'.at the bedside.

The Waist hip ratio is measured by dividing the waist circumference in centimetres by the hip circumference in centimetres.

Waist circumference is measured mid-way between the superior iliac crest and the lower costalmargin in the midaxillary line. The waist is measured by taking a circumference that gives the narrowest measurement between the ribcage and the iliac crest.

Hip circumference is measured as 1 /3rd the distance between anterior superior iliac spine and the patella. The hip measurement is taken by measuring at a level that gives the maximal measurement of the hip,over the buttocks and the morbidity and mortality risk increased if the waist hip ratio > 0.95 in males or > 0.8 in females.

What are the clinical association of obesity?
  • Diabetes mellitus. 
  • Systemic hypertension,
  • Ischaemic heart disease,
  • Hyperlipidaemia 
  • Insulin resistance may be associated with abdominal (truncal) obesity, 
What are the common causes of obesity :
  • Idiopathic (simple obesity).
  • Physical inactivity (sedentary habit).
  • Cushing’s syndrome.
  • Hypothyroidism (primary).
  • Hypothalamic disorders (Frochlich’s syndrome).
  • Insulinoma.
  • Laurence-Moon-Biedl syndrome.
  • Iatrogenic — Prolonged therapy with steroid or oestrogen
What are the types of Obesity

1. Generalised obesity 
Over eating is the most common cause
In generalised obesity there is excess fat deposition uniformly throughout the body.This is the most common type. It is characterised by the presence of a'double chin,.

2. Android obesity .It is a type of obesity, this is characterised by excess deposition of fat over the region of the waist.

3. Gynoid obesity It is a type of obesity, this is characterised by excess deposition of fat over the region of the hips and thighs.

4. Superior or central type of obesity: In this type there is excess fat deposition over face, neck and upper part of the trunk and the arms are thin. This is seen in Cushing's syndrome.

Waist-hip ratio and type of obesity and Prognosis
1.Waist-hip ratio 0.8 or less  associated with Pear-shaped obesity and has Good prognosis
2.Waist-hip ratio 0.9 or greater associated with Apple-shaped obesity and has  Greater risk Increased risk of  developing complications of obesity

What is nutrition and how will you assess it ?

The state of nutrition depends mainly on the distribution of adipose tissue in the body.Based on nutrititonal status people are classified as 
Normal weight
• Underweight
• Overweight
• Obese
How will you assess the state of nutrition at bed side?
1.Ideal body weight (IBW)
Ideal body weight (IBW) = 22.5 x (height in metres)2
In females, the ideal body weight is calculated as = 0.94 x 22.5 x (height in metres)2
If the body weight is more than 10% of IBW the person is overweight.
If the body weight (IBW) is more than 20% the individual is said to be obese.
2.Body mass index
BMI is calculated as follows.
Weight in kg/(height in metres)2
Thc normal range of BMI is 19-25
In males, it is 20-25 '
In females, it is 18-23
If BMI is between 25 and 30, the individual is overweight
If BMI is more than 30 individual is obese.
How to Grade Obesity based on BMI
Grade I  - if BMI 25-30 (over weight)
Grade II  -  if BMI 30-40 (obese)
Grade III - if BMI > 40 (very ohese)
3.Measurement of subcutaneous fat
The amount of subcutaneous fat can be estimated by measuring the skinfold thickness over the triceps.biceps,subscapular region and suprailiac region by special pair of calipers(Harpendencalliper). Equations and normograms  can be used  for conversion of skin fold thickness to bodyfat.
Subcutaneous fat is assessed by picking up the skinfold  between the indexfinger and thumb.
Normal triceps skin fold thickness adult males 12.5mm
Normal triceps skin fold thickness adult females 16.5mm
4.Bulk of musle mass  
Muscle mass can be measured with a tape. Usually mid arm circumference or mid-thigh circumference is taken from the elbow or knee joint respectively (i.e. from a fixed bony pointl
In the presence of generalised odema (anasarca) the nutrition cannot be properly assessed. 
Skinfold thickness in the midtriceps region (midway between acromion and elecranon process, when the arms are hanging by the side of the body) is the most commonly used method.Othernsites examined are biceps, infrascapular and supraiiac region.
4.BROCAS index 
Rough calculation of body weight can be obtained with Brocas index.
To use Brocas index the height of the person  should be > 100 cm, hence it is possible in adults only.
Height in  cm - 100 = desired body weight in kg
Height in inches = body weight (in kg).
5.Signs of vitamin and mineral deficiency
Search for the signs of glossitis ,chelitis ,angularstomatitis,Xerophthalmia,bitots spots and koilonychia which indicate underlying nvitamin and mineral deficiency