ABSTRACT
Context: the prevalence of overweight and obesity are increasing worldwide and have frequently been associated with health risks. This review highlighted several studies regarding obesity, outlining contributions of over a span of almost two decades in the Tehran Lipid and Glucose Study [TLGS]
Evidence Acquisition: a systematic review was undertaken to retrieve articles related to all aspects of obesity from the earliest available date up to January 30, 2017
Results: prevalence of excess weight, including overweight and obesity were 20.8 and 63.6% among those aged below and above 20 years, respectively. TLGS found a high incidence of obesity with higher incidence in women among Tehranian adults; the cumulative incidence of obesity was 31.3, 38.1 and 23.4% for the whole population, women, and men, respectively. In children and adolescents, younger non-obese 7 - 9 years old, compared to 10 - 11 year olds are at greater risk of obesity. Prevalences of abdominal obesity in men and women were 52.8% and 44.4% respectively. Similar to generalized obesity, a high incidence of abdominal obesity was observed; the total cumulative incidence of abdominal obesity was 76.0% [83.6% for men and 70.9% for women]. Metabolically healthy obese [MHO] and metabolically healthy abdominal obese [MHAO] are two important obesity phenotypes. People with these phenotypes have different risks for cardiovascular disease [CVD], type 2 diabetes [T2DM], and mortality. In the TLGS participants, MHO was found in 2% and 7.7% of the whole and obese population, respectively, whereas MHAO phenotype was reported in 12.4% and 23.5% of the whole and abdominal obese population. In these unstable conditions, during the long term follow up the metabolic risks developed in nearly half of the individuals. During a 12-year follow-up, incident CVD did not increase in the MHO phenotype compared to metabolically healthy normal weight [MHNW] individuals, but the risk of CVD events had increased in all metabolically unhealthy phenotypes. However in another report, over a 10-year follow-up, MHAO phenotype had an increased risk for CVD in comparison to the reference group, metabolically healthy non-abdominal obese [MHNAO] individuals
Conclusions: the TLGS studies bridged the significant gap in knowledge regarding prevalence, incidence, trends, morbidities and mortalities for obesity among Iranian population