Effect Of Serum Ferritin On Bone Metabolism In Patients With Type 2 Diabetes Mellitus

Background With the development of social economy,and the change of people's lifestyles,diabetes mellitus(DM),particularly type 2 diabetes,which is closely related to obesity and metabolic disorders,affects more and more patients in developed and developing countries.It has gradually become an important factor that endangers the health of the global public and has caused a great economic burden on the society.Osteoporosis(OP)is a type of systemic bone disease characterized by low bone mass,bone structural microstructural damage,and increased brittleness of the bones and prone to fractures.With the aging of the population,the incidence of osteoporosis has also increased year by year.The most serious consequence of osteoporosis is osteoporotic fractures,so-called fragility fractures,which have a 40% chance of occurring in the patient's life cycle.Unlike ordinary fractures,osteoporotic fractures heal slowly and require longer recovery times,which has a greater impact on the patient's daily life.Osteoporosis,which occurs on the basis of diabetes,is known as diabetic osteoporosis(DOP)and is now considered a chronic complication of diabetes.About 1/2 to 2/3 of diabetics were associated with reduced bone mineral density,and nearly 1/3 of them were diagnosed with osteoporosis.It is particularly important to study the causes of abnormal bone metabolism in diabetic patients and to take intervention measures.In recent years,the correlation between trace elements and bone metabolism has attracted more and more attention,especially iron.A number of studies have suggested that iron is associated with bone metabolism.High serum ferritin levels are a risk factor for osteoporosis,but most studies are mainly directed at non-diabetic people.The study found that diabetics had higher levels of serum ferritin than non-diabetic people,and the incidence of abnormal bone metabolism in diabetic patients was also higher than that of non-diabetic people.What role does serum ferritin play in them? No studies have been conducted yet.Our study is to investigate the effect of serum ferritin on bone metabolism in patients with type 2 diabetes.Objective To explore how iron metabolism affects bone metabolism in patients with type 2 diabetes by analyzing the levels of serum ferritin in different bone mineral density and its relationship with glucose and lipid metabolism,liver and kidney function,and bone turnover markers in patients with type 2 diabetes.Methods A total of 122 patients aged over 50 years with type 2 diabetes mellitus admitted to the Department of Endocrinology of the First Affiliated Hospital of Zhengzhou University from December 2017 to March 2018 were enrolled in this study,including 74 males and 48 females,aged 52-89 years old,mean age(65.84±6.80)years old.Record general clinical data such as gender,age,diabetes course,height,weight,and body mass index(BMI).All patients were fasted for 8-10 hours and then on the second day of the morning,blood samples were taken to measure electrolytes,liver and kidney function,blood lipids,fasting blood glucose(FBG),fasting C-peptide,parathyroid hormone(PTH),aminoterminal prepeptide type I procollagen(PINP),25-hydro xyvitamin D3(25(OH)D3),osteocalcin(OC),?-C-terminal telopeptide of type I collagen(?-CTX),serum ferritin(SF)and other indicators.Using the American HOLOGIC dual-energy X-ray absorptiometry instrument,bone mineral density was measured in all patients on the L1-4 anteroposterior and left hip.All patients were divided into 3 groups according to bone mineral density test results: normal bone density group,bone density reduction group and osteoporosis group.The difference of serum ferritin level between the three groups was compared with the SPSS20.0 professional statistics software,and the correlation between serum ferritin and glycometabolism,lipid metabolism,liver and kidney function,and bone turnover markers was analyzed.Results 1.Comparison of general data among three groups(1)There was no significant difference in gender distribution,age and course of disease between the three groups(P>0.05);(2)Compared with the normal bone density group and the bone density reduction group,the BMI in the osteoporosis group was decreased,and the difference was statistically significant(P<0.05).2.Comparison of general biochemical indicators among three groups(1)There was no significant difference in ALT,AST,ALP,Cr,e GFR,Ca,P,and FBG between the normal density mass,bone density reduction group,and osteoporosis group(P> 0.05);(2)Compared with the normal bone density group: HDL-C in bone density reduction group decreased;TG,TC,LDL-C in osteoporosis group increased;the difference was statistically significant(P<0.05).Compared with the bone density reduction group,TC,LDL-C in osteoporosis group increased,the difference was statistically significant(P<0.05).3.Comparison of Serum Ferritin Levels among three groups Compared with the normal bone density group,serum ferritin levels in the bone density reduction group and the osteoporosis group were significantly higher(P<0.05);compared with the bone density reduction group,serum ferritin levels in the osteoporosis group were significantly higher(P<0.05).4.Correlation analysis of serum ferritin with glycometabolism,lipid metabolism,liver and kidney function,and bone turnover markers The Spearman correlation analysis shows:(1)Correlation analysis with glucose metabolism indicators: serum ferritin levels were positively correlated with fasting blood glucose and Hb A1 c,and the correlation coefficients were 0.362(P<0.05),0.482(P<0.05);serum ferritin levels were negatively correlated with fasting C-peptide,and the correlation coefficients were-0.402(P<0.05);(2)Correlation analysis with lipid metabolism indicators: serum ferritin levels were positively correlated with TG,TC,and LDL-C,and the correlation coefficients were 0.378(P<0.05),0.529(P<0.05),and 0.485(P<0.05);Serum ferritin level was negatively correlated with HDL-C,and the correlation coefficient was-0.458(P<0.05).(3)Correlation analysis with liver and kidney function indicators: There were no statistical differences in the correlation between Serum ferritin levels and Cr(r=-0.154,P>0.05),e GFR(r=0.044,P>0.05),ALT(r=-0.117,P>0.05,AST(r=-0.097,P>0.05).(4)Correlation analysis with bone turnover markers: serum ferritin levels were positively correlated with ?-CTX,and the correlation coefficients were 0.346(P<0.05);There were no statistical differences in the correlation between Serum ferritin levels and ALP(r=0.168,P>0.05),PINP(r=0.021,P>0.05),OC(r=0.026,P>0.05),25(OH)D3(r=0.078,P>0.05),PTH(r=0.021,P>0.05).Conclusions: 1.Increased serum ferritin levels are associated with reduced bone mineral density in type 2 diabetics.2.Serum ferritin may participate in osteoporosis by enhancing the activity of osteoclasts.3.Serum ferritin may be involved in the occurrence and development of diabetic osteoporosis through affecting the glucose and lipid metabolism of patients with type 2 diabetes.