تحليل چند متغيره شاخص چاقي كودكان زير دوسال و رابطه ساختاري آن با چاقي والدين آنها در شيراز

Obesity pattern of south iranian infants and their parents

Obesity (a scaled weight-by-height index) charts of a cohort of 317 healthy infants and their parents living in Shiraz (Southern Iran) are presented, and the familial pattern of infantʹs obesity with that of its parents explored. An adjusted weight-for-height was used to develop power type obesity indices, Ip=W/H^2. Polynomial modelling was used by applying the HRY (Healy, Rasbash. Yang) nonparaunetric method to estimate age-related smoothed centiles of obesity. Principal component analysis (PCA) was applied to analyse the data as continuous variables to analyse familial pattern of parent-infant obesity structurally. The optimal value of p was found to be 2.5 for infants and 1 for their parents. No more than cubic and quadratic polynomials were needed to fit obesity-for-age smoothly for infant and their parents respectively. Infant obesity increases from birth to six months of age and decreases later on to the age of 21 months when it becomes stable. Parent obesity lies below the NCHS standard. Obesity indices and circumferences sizes were reduced to two principal components interpreting infants as well as family obesity. A structural analysis indicates a direct relationship between obesity of parents and infants. A local standard for assessing obesity in clinical practice as well as comnmunity health programmes in Iran is of urgent need, for which our data serves this purpose.