Prevalence of anemia and its associated factors among patients with type 2 diabetes mellitus in a referral diabetic clinic in the north of Iran

BACKGROUND

PURPOSE: This study intended to investigate the prevalence of anemia and its associated factors among patients with type 2 diabetes mellitus (T2DM) in Gorgan, Iran.

METHODS

This cross-sectional study was conducted on 415 (109 men) patients with T2DM referred to the referral diabetes clinic of Sayad Shirazi Hospital in Gorgan in 2021. Demographic information, anthropometric indices, past medical history,  and some laboratory data on cell counts, serum blood glucose, HbA1c, creatinine, lipid/iron profiles, and urinary albumin were collected. The univariable and multivariable logistic regression analysis was applied to compute odds ratios (ORs) and 95% confidence intervals (CI) for potential associated factors, using SPSS version 21. The multivariable Model was adjusted for obesity, Hb A1c, T2DM duration, using glucose-lowering drugs (GLDs), chronic kidney disease (CKD), albuminuria, hypertriglyceridemia, and hypercholesterolemia.  RESULTS: The prevalence of anemia was 21.5% [95%CI: 17.6-25.7] among our total participants. The corresponding values for men and women were 20.2 (13.1-29.0) and 21.9 (17.4-27.0), respectively.The adjusted model revealed that obesity (OR, 1.94 [95% CI, 1.17-3.23]), T2DM duration for more than five years (OR, 3.12 [1.78-5.47]), albuminuria (OR, 6.37 [3.13-10.91]), chronic kidney disease (OR, 4.30 [ 2.83-7.29]) and hypertriglyceridemia (OR, 1.72 [ 1.21-2.77]) were significantly associated with prevalent anemia among patients with T2DM. Moreover, using insulin separately or in combination with oral GLDs associated positively with the prevalence of anemia with ORs of 2.60 [1.42-6.42] and 1.87 [1.30-4.37] , respectively.

CONCLUSION

Anemia had a high prevalence among patients with T2DM in the north of Iran (about 22%), which is associated with obesity, hypertriglyceridemia, duration of T2DM, and diabetic kidney disease.

[Searching for additional markers of impaired iron metabolism in diabetes mellitus]

BACKGROUND

It is known that metabolic disorders in diabetes mellitus have a regulating effect on ferrokinetics, and therefore diabetes mellitus is often accompanied by various disorders of iron metabolism, both anemia and secondary iron overload. The main problem is timely and accurate differential diagnosis between anemia of chronic diseases and iron deficiency anemia. It is necessary to establish reliable laboratory markers of anemia of chronic diseases in order to solve this problem, as well as to understand what metabolic disorders can lead to the occurrence and aggravate the course of this type of anemia.

AIMS

To study the frequency of occurrence of violations of ferrokinetics in patients with diabetes mellitus, as well as to establish clinical and biochemical correlations that are significant in the differential diagnosis of various disorders of iron metabolism: iron deficiency anemia, anemia of chronic diseases and dysmetabolic iron overload syndrome in diabetes mellitus.

MATERIALS AND METHODS

The research design a single-stage observational single-center research. The research was conducted on the basis of the endocrinological clinic of the Federal State Budgetary Educational Institution of Higher Education Siberian State Medical University in Tomsk. The research included 76 patients with type 1 and type 2 diabetes mellitus. We conducted an assessment of all patients as follows: anthropometric data assessment; glycated hemoglobin study; creatinine level study with the calculation of glomerular filtration rate (GFR) using the CKD-EPI formula. We also evaluated the number of erythrocytes, reticulocytes, the hemoglobin concentration, haematocrit level and biochemical parameters of iron metabolism: serum iron and ferritin concentrations; the concentration of hepsidin and non-specific markers of inflammation: erythrocyte sedimentation rate (ESR) and highly sensitive C-reactive protein (CRP).

RESULTS

20 people (26.3%) of the 76 patients included in the study, had type 1 diabetes mellitus and 56 people (73.3%) had type 2 diabetes mellitus. The parameters of ferrokinetics did not significantly differ in patients with type 1 and type 2 diabetes mellitus, while in the group of patients with 20 patients (26.3%) from the 76 ones included into the research had type 1 diabetes mellitus and 56 (73.3%) from them had type 2 diabetes mellitus. The parameters of ferrokinetics did not significantly differ in patients with type 1 and type 2 diabetes mellitus, while in the group of patients with type 2 diabetes mellitus, the levels of CRP (p=0.034) and blood leukocytes (p=0.020) were significantly higher than in patients with type 1 diabetes mellitus. Both in the main group of patients with impaired carbohydrate metabolism, and in patients with type 2 diabetes mellitus, anemia of chronic diseases prevailed in the structure of the anemia syndrome. After dividing the main group of patients into groups by type of anemia syndrome: absence of anemia, anemia of chronic diseases and iron deficiency anemia, a comparative analysis of the average values of markers of inflammation and the level of hepsidin in these groups was performed. It was found that in patients with anemia of chronic diseases, the level of hepsidin is significantly higher than in patients without anemic syndrome (p=0.033). Paired correlation analysis showed a positive correlation of ESR with microalbuminuria (r=0.515; P<0.0001), creatinine level (r=0.467; P<0.0001) and negative — with GFR (r= -0.436; P<0.0001) and iron in serum (r=-0.276; p=0.017). As the result of ROC analysis the most informative in the diagnosis of anemia of chronic disease were: ferritin — sensitivity 78%, specificity 52% with a diagnostic threshold of 75.5 ng/ml (area under the curve 0,695; p=0.006); ESR — sensitivity 67%, specificity 64% with a diagnostic threshold of 15.5 mm/HR (area under the curve of 0.750 in; p=0.040) and the CRP — sensitivity 67%, specificity 64% with a diagnostic threshold of 5.2 ng/ml (area under the curve 0,646; р<0.0001).

CONCLUSION

Thus, the studied markers of inflammation — ESR and CRP, as well as hepsidin in combination with the classic diagnostic parameter — ferritin, demonstrated high value in the diagnosis of anemia of chronic diseases and can be included in the modified algorithm for differential diagnosis of anemia syndrome in patients with diabetes mellitus.

Correlations between Iron Metabolism Parameters, Inflammatory Markers and Lipid Profile Indicators in Patients with Type 1 and Type 2 Diabetes Mellitus

This study aims to establish relationships between inflammatory status, ferrokinetics and lipid metabolism in patients with diabetes mellitus. Subclinical inflammation was assessed by levels of high-sensitive C-reactive protein, tumor necrosis factor-α and erythrocyte sedimentation rate. Iron metabolism parameters included complete blood count, serum iron, transferrin and ferritin. Metabolic status assessment included lipid profile, glycated hemoglobin and microalbuminuria measurement. As a result of the study it was possible to establish both general (universal) and diabetes mellitus (DM) type-dependent relationships between the parameters of lipid profile and metabolic control in DM. High-density lipoprotein cholesterol (HDL-C) levels negatively correlated with microalbuminuria (r = −0.293; p ˂ 0.05 for type 1 diabetes and r = −0.272; p ˂ 0.05 for type 2 diabetes). Ferritin concentration positively correlated with triglyceride level (r = 0.346; p ˂ 0.05 for type 1 diabetes and r = 0.244; p ˂ 0.05 for type 2 diabetes). In type 1 diabetes, a negative correlation was discovered between estimated glomerular filtration rate (eGFR) and LDL-C (r = −0.480; p ˂ 0.05), very low-density-lipoprotein cholesterol (VLDL-C) (r = −0.490; p ˂ 0.05) and triglycerides (r = −0.553; p ˂ 0.05), and a positive one between C-reactive protein concentration and triglyceride level (r = 0.567; p ˂ 0.05). Discovered relationships between lipid profile indices, inflammatory status and microalbuminuria confirmed mutual influence of hyperlipidemia, inflammation and nephropathy in diabetes patients. Obtained results justify the strategy of early hypolipidemic therapy in patients with diabetes mellitus to prevent the development and progression of microvascular complications.