This page comprises of the most useful landmarks developed out of years of clinical acumen and which help immensely in the accurate assessment of exact clinical situation in a case.
Team Tracemydoctor publishes an elaborate account of these health-calculators and health-scores to enable our viewers to get a deep understanding of their usefulness.It is further advised that a final opinion on such technical and clinical issues could only be formed by a licensed medical practitioner.
Readers are requested to visit mdcalc.com for detailed inputs.
BODY MASS INDEX(BMI)
BODY MASS INDEX(BMI)– This index attempts to quantify the amount of tissue mass (mainly muscle,fat and bone) in an individual thus categorizing a person as underweight, normal & overweight/obese.It is a useful indicator of obesity associated with sedentary life in addition to indicating food habit disorders (eating less/more than needed).
Kindly visit a health quiz (Am I fit,fat or obese?) before proceeding further.
Following salient features related to BMI should be understood first before diving deep into its intricacies:
- BMI has been used by WHO as the standard for recording obesity in large populations since the early 1980s.
- BMI is also called Quetelet index defined as the body mass(weight in kgs) divided by the square/second power of height(in metres).
- Its scalability is such that it results in taller people having a reported BMI that is uncharacteristically high compared to their actual body fat levels.
- This drawback in its scalability is removed in Ponderal index(discussed later) which is based on the natural scaling of mass with the cube/third power of the height.
- Duality of BMI makes it suitable for a general routine calculation only in identifying trends within sedentary or overweight individuals because of lesser margin of error in such people.
- BMI is excellent in quantifying people in categories of under-weight,normal-weight and over-weight in large populations but are far less reliable for determining fatness(adiposity) in individuals.
- Growth of a child is routinely monitored by BMI- measured growth charts.
- BMIs under 20 and over 25 have been associated with higher all cause mortality.
- Among people who have never smoked, over-weight/obesity is associated with 51% increase in mortality compared with people who have normal weight.
- The prevalence of obesity is highest in America and lowest in South East Asia.
- The prevalence of obesity is more than double in high income groups.
- Cross-sectional studies have indicated that sedentary people can reduce their BMI by increasing their physical activity.
- BMI PRIME is a modification of BMI system which is the ratio of actual BMI to upper limit optimal BMI (25kg/m square in Americans and 23kg/m square in south east Asians). It is useful clinically as it shows by what ratio or percentage a person deviates from the maximal optimal BMI.
- BMI PRIME value below 0.74 is underweight, 0.74-1.00 is optimal and above 1.00 is overweight.
PONDERAL INDEX(PI)/CORPULENCE INDEX(CI)
BASAL METABOLIC RATE
BASAL METABOLIC RATE(BMR)– This is the amount of energy per unit time that an individual needs to keep the body functioning at rest.A person’s metabolic rate varies with his/her physical activity.A decrease in food intake typically lowers the rate as the body tries to conserve energy.
Many drugs affect BMR.This rate may be elevated in stress, diabetes and hyperthyroidism.Stages in growth and development like puberty, menopause and senility also affect BMR.This is a helpful tool for maintaining healthy body weight.