Changes in Obesity Odds Ratio among Iranian Adults, since 2000: Quadratic Inference Functions Method

Abstract

Background. Monitoring changes in obesity prevalence by risk factors is relevant to public health programs that focus on reducing or preventing obesity. The purpose of this paper was to study trends in obesity odds ratios (ORs) for individuals aged 20 years and older in Iran by using a new statistical methodology. Methods. Data collected by the National Surveys in Iran, from 2000 through 2011. Since responses of the member of each cluster are correlated, the quadratic inference functions (QIF) method was used to model the relationship between the odds of obesity and risk factors. Results. During the study period, the prevalence rate of obesity increased from 12% to 22%. By using QIF method and a model selection criterion for performing stepwise regression analysis, we found that while obesity prevalence generally increased in both sexes, all ages, all employment, residence, and smoking levels, it seems to have changes in obesity ORs since 2000. Conclusions. Because obesity is one of the main risk factors for many diseases, awareness of the differences by factors allows development of targets for prevention and early intervention.

Assessing longitudinal and cross-sectional effects of age on adult obesity in an Iranian population: results from a large population-based cohort study

“…Shifts in diets and eating behavior which include energy-dense foods, high in sugars and fat, higher consumption of red meat, salt, and saturated fatty acids among individuals because of the increasing economic status, and less physical activity due to the sedentary work styles, types of transportation and changes in lifestyle are combining to increase the possibility of becoming obese (4). This rate of increase is also reported by other studies (1,6,15,16,30). In both developed and developing countries and speci cally in middle-east countries, the prevalence of obesity is rising at alarming rates (1, 4, 13).…”

“…In another study in the USA, an independent crosssectional effect of age on obesity was reported and also, a higher probability for obesity in younger Baseline Age groups in comparison to older individuals after controlling the aging effects were observed (21). With increasing age, there are alterations in food intake, energy consumption, and appetite besides bone and muscle loss that affect body composition (30).…”

“…In our study, for both groups of men and women, the average BMI and WC were raised over 12 years (2001 -2013), but women had a higher average BMI and WC than men in all three phases. Among women, lower physical activity level, pregnancy, menopause, a higher rate of depression, lack of employment, lower socioeconomic status, lower educational level, and gender differences in food intake may be some of the causes for the higher prevalence of obesity in comparison with men (30,(32)(33)(34). Iranian women pay less attention to their body shape in comparison to European and Oceanic women and also, less information and knowledge about weight loss may be another cause (15) Considerable regional differences in BMI alters through time were reported in different studies.…”

Assessing longitudinal and cross-sectional effects of age on adult obesity in an Iranian population: results from a large population-based cohort study

“…In our study, for both groups of men and women, the average BMI and WC were raised over 12 years (2001 -2013), but women had a higher average BMI and WC than men in all three phases. Among women, lower physical activity level, pregnancy, menopause, a higher rate of depression, lack of employment, lower socioeconomic status, lower educational level, and gender differences in food intake may be some of the causes for the higher prevalence of obesity in comparison with men (30,(32)(33)(34). Iranian women pay less attention to their body shape in comparison to European and Oceanic women and also, less information and knowledge about weight loss may be another cause (15) Considerable regional differences in BMI alters through time were reported in different studies.…”

Assessing longitudinal and cross-sectional effects of age on adult obesity in an Iranian population: results from a large population-based cohort study

“…Also, it can be considered as a problem for high-income countries (7)(8)(9). In Iran, several studies reported a high and rising prevalence of obesity (6,(10)(11)(12)(13)(14)(15)(16). Age, place of residence, educational level, gender, and marital status, were indicated as some variables that are associated with inequality in obesity in Iran (11,16,17).…”