Research Article Association between RBC Indices, Anemia, and Obesity-Related Diseases Affected by Body Mass Index in Iranian Kurdish Population: Results from a Cohort Study in Western Iran MaryamKohsari ,MehdiMoradinazar ,ZohrehRahimi,FaridNajafi,YahyaPasdar , Atefeh Moradi, and Ebrahim Shakiba Behavioral Disease Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran Correspondence should be addressed to Mehdi Moradinazar; m.moradinazar@gmail.com Received 28 March 2021; Accepted 27 August 2021; Published 6 September 2021 Academic Editor: Christian S. Goebl Copyright © 2021 Maryam Kohsari et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. e relationship between RBC indices and metabolic diseases remains unclear. e association between anemia and obesity is also controversial. e present study aimed to investigate the relationship between RBC indices and metabolic diseases caused by obesity and evaluate the effect of body mass index (BMI) on RBC indices on the Ravansar cohort data. Method.Forthe purpose of this study, 9826 participants aged 35–65 years (5158 females and 4668 males) were recruited in the analyses. A quadratic prediction fit plot investigated the association between RBC indices with BMI and lipid profile. e odds ratio of obesity-related diseases in each quartile category of RBC indices and anemia was estimated using multivariable logistic regression models. Results. Subjects in the fourth quartiles of RBC count, hematocrit (HCT), hemoglobin (HGB), and red cell distribution width (RDW) had a higher risk for obesity-related diseases compared to the first quartiles. However, individuals with the mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) in fourth quartiles had lower ORs of obesity-related diseases. While BMI reduced the effect of RBC count, HCT, HGB, and RDW on the incidence risk of obesity-related disease, it increased the impact of MCV, MCH, and MCHC. ere was a negative association between BMI and RBC indices except for RDW. e BMI effect on RBC indices was different in normal and obese individuals.BMIinmildanemialoweredtheriskofmetabolicdiseases,butitincreasedtheriskofmetabolicdiseasesformoderate anemia. Conclusion. A higher risk of obesity-related diseases was observed in the fourth quartiles of RBC count, HCT, HGB, and RDW compared to the first quartiles. However, the incidence risk was lower for MCV, MCH, and MCHC. BMI plays an anemia- type dependent role in the relationship. Consideration should be given to the type of anemia in the relationship between BMI and anemia. 1. Introduction Obesity is defined as the body mass index (BMI) ≥30kg/m 2 [1]. e rate of obesity has grown so dramatically in the last three decades that in 2014, almost 30% of the world’s population was considered overweight and obese, and the numberisestimatedtoreach50%markby2030[2].erole of obesity in metabolic diseases including diabetes mellitus (DM), cardiovascular disease (CVD), metabolic syndrome (MetS) [3], and hypertension (HTN) [4] is clearly under- stood. Obesity has a potent correlation with dyslipidemia that contributes to CVD risk developments [5], and an increase in BMI leads to the progression of heart damage [4] and nonalcoholic fatty liver disease (NAFLD) [6]. Recently, the role of red blood cell (RBC) indices was identified in metabolic diseases. e complete blood count (CBC) test which is routinely administered in medical ex- aminationscanbeutilizedintheearlydetectionofmetabolic disorders [7]. However, there are limited studies that in- dicate the role of RBC indices in the incidence of metabolic diseases. A number of reports have suggested that red cell distribution width (RDW) reduced the risk of MetS [8] and Hindawi International Journal of Endocrinology Volume 2021, Article ID 9965728, 13 pages https://doi.org/10.1155/2021/9965728