Rapid Responses to:
|
|
Rapid Responses: Rapid Responses published:
-
![[Read Rapid Response]](/icons/misc/sectionDOWN.gif)
Unreliability of Indices of Weight & Height In Assessment of Nutritional State In Children:
- SUJOY GHOSH, APARAJITA BASU (27 July 2007)
|
|
|||
|
SUJOY GHOSH, Clinical Teaching & Clinical Research Fellow The Ayr Hospital, Ayr, Scotland, UK, APARAJITA BASU
Send response to journal:
|
Dr. Sujoy Ghosh *, Dr. Aparajita Basu *Clinical Teaching & Clinical Research Fellow, The Ayr Hospital, Scotland, United Kingdom Email: drsujoyghosh@rediffmail.com We have read with interest the original research paper by Cole et al. as well as the accompanying editorial. [1, 2]. The authors attempt of trying to determine cut offs to define thinness in children and adolescents based on body mass index at age 18 years is indeed commendable. However the study has its own limitations. The editorial correctly points out the limitations of using same cut offs for males and females and also highlights the fact that the measures are not adjusted for pubertal development or the tempo of adolescent growth and maturation. The assumption that a BMI of 17 at age 18 is a suitable cut off to use as the basis for an international definition of thinness in children and adolescents is arbitrary and is indeed an oversimplification of the complex process of growth and development in children. Conventionally weight for height less than the fifth percentile or above 95th percentile had been regarded as the best growth chart indicator of problems of nutrition. [3] In recent years indices of height and weight, such as body mass index (BMI = weight/height2) has used as a measure of nutritional state. Although BMI is widely used as a clinical measure of nutrition, BMI may not provide an accurate index of adiposity, because it does not differentiate lean tissue and bone from fat. [4]. It is estimated that ~15% of children labeled as obese are not excessively fat, but simply have large fat free mass. Triceps-skin fold above a cut off of 95th centile (though difficult to apply in clinical practice) has the advantage of distinguishing a child who is excessively fat from the child who has a particularly large fat- free (‘lean body’) mass. [5] Disease states are often associated with abnormalities of growth. In these states often there are associated abnormalities in the onset and progress of puberty. The body composition is also often altered with disease states, making assessment of nutritional status with the help of indices of height and weight (such as BMI) even more complex and unreliable. [6] Clinicians need to be aware that no single measure/index is perfect in assessing nutritional status of a patient. The assessment of nutritional status therefore should not be based on one measurement or one index. Serial measurements are more important than a single one. In addition direct measures of body composition such mid-arm circumference, skin fold thickness, impedance measurements should be used for cross- validation. COMPETING INTEREST: None REFERENCES: [1] Cole TJ, Flegal KM, Nicholls D, Jackson AA. Body mass index cut offs to define thinness in children and adolescents: international survey. BMJ. 2007; 355: 194-197 [2] Cameron Noel. Body mass index cut offs to define thinness in children and adolescents.BMJ 2007; 355: 166-167. [3] Behrman R E, Kliegman, Jenson H B. Assessment of Growth. Nelson Textbook of Pediatrics. 16th Edition, 2000, W.B. Saunders Company. Page:57 -61. [4] Dietz W H. Therapeutic strategies in childhood obesity. Hormone Research 39 (Suppl 3): 86-90. [5] Dietz W H. Childhood obesity. In: Suskind RM, Lewinter-Suskind L (eds). Textbook of pediatric nutrition, 2nd edn. Raven Press, New York, 1993. [6] Warner J T, Cowan F J, Dunstan FDJ, Gregory JW. The validity of body mass index for the assessment of adiposity in children and disease states. Ann Hum Biol 1997; 24: 209-15. Competing interests: None declared |
|||