Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary's Campus, Norfolk Place, London, W2 1PG, UK.
Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, UK.
BMC Endocr Disord. 2023 Aug 2;23(1):161. doi: 10.1186/s12902-023-01423-1.
Obesity is associated with type 2 diabetes mellitus and chronic low-grade inflammation. Although chronic inflammatory conditions and diabetes are associated with anaemia, less is known about associations of obesity and body shape, independent of each other, with erythrocyte and reticulocyte parameters.
We investigated the associations of body mass index (BMI) and the allometric body shape index (ABSI) and hip index (HI), which are uncorrelated with BMI, with erythrocyte and reticulocyte parameters (all continuous, on a standard deviation (SD) scale) in UK Biobank participants without known metabolic, endocrine, or major inflammatory conditions (glycated haemoglobin HbA1c < 48 mmol/mol, C-reactive protein CRP < 10 mg/L). We examined erythrocyte count, total reticulocyte count and percent, immature reticulocyte count and fraction (IRF), haemoglobin, haematocrit, mean corpuscular haemoglobin mass (MCH) and concentration (MCHC), mean corpuscular and reticulocyte volumes (MCV, MRV), and red cell distribution width (RDW) in multivariable linear regression models. We additionally defined body shape phenotypes with dichotomised ABSI (≥ 73 women; ≥ 80 men) and HI (≥ 64 women; ≥ 49 men), including "pear" (small-ABSI-large-HI) and "apple" (large-ABSI-small-HI), and examined these in groups according to BMI (18.5-25 normal weight; 25-30 overweight; 30-45 kg/m obese).
In 105,853 women and 100,854 men, BMI and ABSI were associated positively with haemoglobin, haematocrit, and erythrocyte count, and more strongly with total reticulocyte count and percent, immature reticulocyte count and IRF. HI was associated inversely with all, but least with IRF. Associations were comparable in women and men. In groups according to obesity and body shape, erythrocyte count was ~ 0.6 SD higher for obese-"apple" compared to normal-weight-"pear" phenotype (SD = 0.3110/L women, SD = 0.3410/L men), total reticulocyte count was ~ 1.1 SD higher (SD = 21.110/L women, SD = 23.610/L men), immature reticulocyte count was ~ 1.2 SD higher (SD = 7.910/L women, SD = 8.810/L men), total reticulocyte percent was ~ 1.0 SD higher (SD = 0.48% women and men), and IFR was over 0.7 SD higher (SD = 5.7% women and men). BMI but not ABSI or HI was associated more weakly inversely with MCV, MRV, and MCH, but positively with MCHC in men and RDW in women.
In obesity uncomplicated with diabetes, larger BMI and ABSI are associated with increased erythropoiesis and reticulocyte immaturity.
肥胖与 2 型糖尿病和慢性低度炎症有关。尽管慢性炎症和糖尿病与贫血有关，但肥胖症和体型（与 BMI 无关）与红细胞和网织红细胞参数之间的关联知之甚少。
我们在没有已知代谢、内分泌或主要炎症疾病的 UK Biobank 参与者中（糖化血红蛋白 HbA1c<48mmol/mol，C 反应蛋白 CRP<10mg/L），研究了体重指数（BMI）和与 BMI 不相关的体型指数（ABSI）和臀围指数（HI）与红细胞和网织红细胞参数（全部连续，在标准差（SD）尺度上）之间的关联。我们在多变量线性回归模型中检查了红细胞计数、总网织红细胞计数和百分比、未成熟网织红细胞计数和分数（IRF）、血红蛋白、血细胞比容、平均红细胞血红蛋白质量（MCH）和浓度（MCHC）、平均红细胞和网织红细胞体积（MCV、MRV）以及红细胞分布宽度（RDW）。我们还通过二分法定义了体型表型，包括 ABSI（女性≥73；男性≥80）和 HI（女性≥64；男性≥49），并检查了这些体型表型在 BMI 组（18.5-25 为正常体重；25-30 为超重；30-45kg/m 为肥胖）中的分布。
在 105853 名女性和 100854 名男性中，BMI 和 ABSI 与血红蛋白、血细胞比容和红细胞计数呈正相关，与总网织红细胞计数和百分比、未成熟网织红细胞计数和 IRF 的相关性更强。HI 与所有这些指标呈负相关，但与 IRF 的相关性最弱。在女性和男性中，这些关联是可比的。在根据肥胖症和体型划分的组中，与正常体重-"梨形"体型相比，肥胖-"苹果形"体型的红细胞计数高约 0.6 SD（女性的 SD=0.3110/L，男性的 SD=0.3410/L），总网织红细胞计数高约 1.1 SD（女性的 SD=21.110/L，男性的 SD=23.610/L），未成熟网织红细胞计数高约 1.2 SD（女性的 SD=7.910/L，男性的 SD=8.810/L），总网织红细胞百分比高约 1.0 SD（女性和男性的 SD=0.48%），IRF 高约 0.7 SD（女性和男性的 SD=5.7%）。BMI 与 MCV、MRV 和 MCH 呈较弱的负相关，但与男性的 MCHC 和女性的 RDW 呈正相关，而 ABSI 或 HI 与这些指标的相关性较弱。
在不伴有糖尿病的肥胖症中，较大的 BMI 和 ABSI 与红细胞生成和网织红细胞不成熟增加有关。
