The Study Of BMD And Its Relevant Factors For Elderly Patients With T2DM

Objective:Diabetes mellitus (DM) is a common disease and its morbidity is increasing year after year nowadays. Long-term chronic increased blood glucose could lead to multisystem damage, which includes calcium-phosphorus metabolism and skeletal system. Diabetic osteoporosis (DOP) is a secondary osteoporosis due to long-time chronic elevated plasma glucose. Many domestic and overseas researchers observe that type 1 diabetes (T1DM) could result in osteopenia, osteoporosis; while the influence of type 2 diabetes (T2DM) on bone mineral density (BMD) is uncertain so far, which could show elevated BMD, or reduced one, even normality. Besides, that BMD is related with age, gender, weight and others is also observed. To explore the changing tendency of BMD of elderly patients with T2DM and its related influencing factors and provide references for evaluating early status of patients with DOP and establishing relevant clinical diagnosis and treatment plan, the BMDs of patients with T2DM were measured by dual energy X-ray absorptiometry (DEXA), and the age, height, weight the fasting plasma glucose (FPG) and suchlike physicochemical indexes were also recorded or detected.Methods:A total of 465 inpatients with T2DM in Gansu Provincial Hospital endocrinology department were selected from Aug.2014 to Nov.2014, which included male patients (284 cases) and female ones(181 cases) and whose age range was from 40 to 90.The diagnosis and classification standards of T2DM were according to World Health Organization (WHO) standards at 1999. All patients received detection of DEXA and the detecting positions were the lumbar vertebra (LI-4) and the left hip (neck of femur, greater trochanter, Troch Wards, femoral shaft). The BMD and corresponding T values were recorded. All patients were assigned as normal bone mass group, osteopenia group and osteoporosis group according to the recommended diagnostic standards of osteoporosis of WHO at 1994. The age, height, weight, disease duration of subjects were recorded and the Body Mass Index (BMI) was calculated and the fasting C-peptide (FCP) and 2 hour postprandial C-peptide (2hCP) levels, glycosylated hemoglobin A1C (GHbAlC), fasting plasma glucose (FPG), fasting insulin (FINS),24 hour urine sugar (24hnt),24 hour urine protein (24hndb) and 24 hour microalbuminuria (24hnwlbdb) were also tested. In the end, the sample statistical data were described and analyzed by Statistic Package for Social Science (SPSS).Results:1. The general clinical data comparison between normal bone mass group, osteopenia group and osteoporosis groupThere was statistical difference at gender ratio, age, height, weight, the BMD and T-score of lumbar vertebra and left hip among these groups (P<0.01). BMI and disease duration-there was statistical difference between normal bone mass group and osteoporosis group (P<0.05), no statistical difference between normal bone mass group and osteopenia group and between osteopenia group and osteoporosis group (P>0.05). In addition, the BMD between the vertebra and left hip exhibits statistical difference (P<0.001), but the T-score between them shows no statistical difference (P>0.05). There was no statistical difference at FCP,2hCP, GHbA1C, FPG, FINS,24hnt, 24hndb and 24hnwlbdb among these groups (P>0.05).2. The BMD comparison between normal bone mass group, osteopenia group and osteoporosis groupThe ratio of normal bone mass group is 58.9% (male 75.9%, female 24.1%)(P<0.001), osteopenia group 25.8% (male 53.3%, female 46.7%)(P>0.05), osteoporosis group 15.3% (male 16.9%, female 83.1%)(P<0.001); the total ratio of reduced BMD of patients is 41.1% (male 39.8%, female 60.2%)(P<0.001).The mean value of BMD of lumbar vertebra(1.058±0.174g/cm2) is duration shows negative (P<0.01) and positive (P<0.05) with height, weight, BMI and FCP. Because the correlation coefficient [BMI--lumbar vertebra/hip:(0.136/0.222);disease duration-lumbar vertebra/hip:(-0.028/-0.153)] of BMI and disease duration is less than 0.3, the relevance between BMI, disease duration and BMD is poor.4. The multiple linear stepwise regression analysis between BMD of T2DM patients and relevant factorsThe results of multiple linear stepwise regression analysis between BMD of T2DM patients and relevant factors show that:the indexes in function are height, gender, weight and FCP at regression model with lumbar vertebra BMD as dependent variable (P<0.20); the indexes in function are weight, age, gender,24hndb and 2hCP at regression model with hip BMD as dependent variable (P<0.20).Conclusions:1. The BMD of lumbar vertebra of elderly patients with T2DM exhibits small variation tendency from decline to increase while the BMD of the hip descending tendency with the process of aging; the morbidity of osteoporosis in female is much higher than that in male.2. The important risk factors of BMD of elderly patients with T2DM are female, aging, lean body, lower insulin secretion function and serious diabetic nephropathy (DN).3. In order to avoid the occurrence and development of DOP, elderly patients with T2DM should understand relevant factors of BMD, carry on periodic physical examination, prevent and intervene at early stages.