Correlation Analysis Between Serum Ferritin And Bone Mineral Density In Patients With Type 2 Diabetes Mellitus

Objective:Osteoporosis is a common clinical disease of middle-aged and elderly,it is a growing public health problem in China.The aim of this study was to explore the association of serum ferritin with bone mineral density in type 2 diabetes（Type 2diabetes mellitus,T2DM）,and to asses its role in predicting osteoporosis in type 2diabetic patients.Methods:We retrospectively reviewed the case data of type 2 diabetes patients who were admitted to the Endocrinology Department of the third affiliated hospital of Nanchang University from January 2015 to January 2020.In strict accordance with the inclusion criteria,exclusion criteria and relevant diagnostic criteria,397 subjects with type 2 diabetes were finally screened for this study.Recording the general data such as gender,ages,heights,weights,history of smoking,medical history,and the course of diabetes of the enrolled patients and laboratory results like the fasting plasma glucose（FPG）,2-hour after meals glucose（2h PG）,glycosylated hemoglobin（Hb A1c）,totally cholesterol（TG）,trayiglyceride（TC）,high-density lipoprotein cholesterol（HDL-C）,low-density lipoprotein cholesterol（LDL-C）,Calccium（CA）,Phase phosphorus（P）,parathyroid hormone（PTH）,Base alkaline phosphatase（BALP）,urine microalb-umin（MALB）,urinary microalbumin to urinary creatinine ratio（ACR）,serum ferritin（SF）,then calculating the body mass index.According to the dual energy X-ray absorption test（DXA）to mensurate the bone mineral density of the enrolled patients,and recording the results of lumbar vertebra（L1～L4）,total lumbar vertebra,bilateral femoral neck and bilateral hip.Groups were divided by age into Group A（age<60 years group）and Group B（age≥60 years group）,then divided into four subgroups according to ferritin levels by the quartile method,Group1:Group less than or equal to 161.90ug/L,Group 2:Group 161.91～263.00ug/L and Group 3:Groups 263.01～396.26ug/L and Group 4:Group more than or equal to396.27ug/L.Analyze the serum ferritin association with bone mineral density and calculate the optimal threshold for serum ferritin to predict the occurrence of osteoporosis in patients with type 2 diabetes.Results:The study included a total of 397 study subjects,there were 149 cases in the group A,Group A₁（Group less than or equal to 161.90ug/L,38 cases）,accounting for25.5%,Group A₂（Group 161.91～263.00ug/L,33 cases）,accounting for 22.1%,Group A₃（group 263.01～396.26ug/L,43 cases）,for 28.9%,and Group A₄（Group396.27ug/L,35 cases）,accounting for 23.5%.There were 248 patients in the group B,Group B₁（Group less than or equal to 161.90ug/L,62 cases）,accounting for25.0%,Group B₂（161.91～263.00ug/L,66 cases）,26.6%,B₃（263.01～396.26ug/L,56cases）,22.6%,and B₄（396.27ug/L,64 cases）,accounting for 25.8%.1.Comparison of the occurrence of osteoporosis between the two age groups:the case rate of osteoporosis in group B was 44.8%,higher than that in group A（20.1%）,with a statistical meaningful variance（P=0.000<0.01）.2.Comparison of age,BMI,and diabetic duration between the four subgroups of different age groups:In group A,BMI among group A₁（25.79±3.50）versus group A₃（24.07±2.81）and A₄（24.18±3.09）,Group A₂（25.69±3.40）versus group A₃（24.07±2.81）,the variance is statistically considerable（P<0.05）.The age and duration of diabetes were not statistically significant among the four groups;in group B,the variation in age,BMI and duration of diabetes were not statistically significant among the four groups.3.Comparison of the various indicators between the four subgroups of different age groups:In group A,there were no statistically meaningful variance in FPG,2h PG,Hb A1c,blood calcium,blood phosphorus,PTH,BALP,TC,TG,HDL-C,LDL-C,MALB,and ACR.In group B,There were no statistically meaningful difference in FPG,2h PG,Hb A1c,blood calcium,blood phosphorus,PTH,TC,TG,HDL-C,LDL-C,MALB,and ACR,While BALP was lower in B₃（101.34±9.79）than in group B₄（107.58±14.34）,indicating a statistically meaningful variance（P<0.05）.4.Comparison of BMD between the four subgroups of different age groups:In group A,significant differences in BMD at all groups,BMD of L1,L2,L3,L4,total lumbar vertebra,left femoral neck,left hip,right femoral neck,and right hip showed an increase in group A₁compared to group A₄（P<0.05）,BMD of L1,L2,L3,lumbar spine sum,left femoral neck,right femoral neck,left hip and right hip showed an increase in group A₂compared to group A₄（P<0.05）,BMD of the right femoral neck and right hip increased in group A₁compared to group A₃（P<0.05）.In group B,there was no significant discrepancy in BMD between the four groups（P>0.05）.5.Comparison of ferritin between the four subgroups of different age groups:In group A,ferritin in A₁（96.70±34.77）<A₂（222.91±29.04）<A₃（327.23±39.86）<A₄（596.48±150.36）,all the differences were statistically significant（P<0.05）.In group B,ferritin was in group B₁（122.45±31.92）<B₂（209.23±28.08）<B₃（326.35±37.82）<B₄（578.42±182.61）,all discrepancies are statistically meaningful（P<0.05）.6.The relevance of serum ferritin to bone mineral density in patients of different age groups:Serum ferritin was adversely linked to lumbar vertebra（L1 to L4）,total lumbar vertebra,bilateral femoral neck,and bilateral hips in group A and B.7.Correlation between BMD and various biochemical parameters in various age groups:Among group A,bone mineral density of L1 was strongly linked to BMI and PTH,the L2 BMD shows a positive correlation with BMI,L3 and L4 BMD presents a favourable correlation with BMI and PTH and adverse correlation with bone alkaline phosphatase and blood phosphorus,total lumbar vertebra BMD was positively associate with BMI,PTH and negatively associated with bone alkaline phosphatase,right femoral neck BMD,left femoral neck,right hip BMD,and left hip BMD presents a favourable correlation with BMI and negatively associated with urinary microalbumin and ACR.In group B,L1 bone density shows a positive correlation with BMI and a negative association with bone alkaline phosphatase,TC,HDL-C,and blood phosphorus,L2 and total lumbar vertebra BMD has a optimistic correlation with BMI and negative correlation with bone alkaline phosphatase,TC,and HDL-C,L3 BMD was optimistic correlated with BMI and and negatively interrelated with TC,HDL-C,and LDL-C,L4 BMD presents a favourable correlation with BMI and a negative correlation with TC and HDL-C,both left and right femoral neck BMD,right and left hip BMD were orthogonal correlate with BMI,and negatively in relation to age,TC,and HDL-C.8.The potency of serum ferritin predicting OP occurrence in patients with type2 diabetes mellituswas was obtained by using the subject operating characteristic curve（ROC curve）:Among group A,the region under the curve was 0.749 and the ferritin threshold was 312.25ug/L,P=0.000<0.01,The Youden index was 0.456,with a sensitivity of 76.7%and specificity of 68.9%.Among group B,the region under the curve was 0.615 and the ferritin threshold was 250.3ug/L,P=0.002<0.01,Yoden index 0.191,sensitivity of 62.2%and specificity of 56.9%.Conclusion:1.BMD at every part decreased with increasing serum ferritin levels in patients with type 2 diabetes mellitus.2.Serum ferritin is inversely associated with bone mineral density in type 2diabetes mellitus and is a risk factor for decreased bone mass in this population.3.The optimal threshold for serum ferritin to predict osteoporosis in type 2diabetes was 312.25ug/L at age below 60 years and 250.3ug/L at age higher than 60years.Monitoring serum ferritin level can detect the occurrence of osteoporosis in type 2 diabetes patients early a certain extent and conduct timely clinical intervention.