Influence of pranayamas and yoga-asanas on serum insulin,blood glucose and lipid profile in type 2 diabetes

A distinguishable feature of type 2 diabetes besides hyperglycemia and deranged lipid profile is an impaired insulin secretion, peripheral insulin resistance and obesity which has become a major health concern worldwide. India with an estimated 31million diabetics in 2000 and 79mllions by the yr 2030 has the highest number of type 2 diabetics in the world. In this study, we aimed to see if yoga-asanas and pranayamas have any influence in modifying certain biochemical parameters. Sixty patients of uncomplicated type 2 diabetes (age 35–60 yrs of 1–10 yrs duration) were divided into two groups: Group 1 (n=30): performed yoga along with the conventional hypoglycemic medicines and group 2 (n=30): patients who only received conventional medicines. Duration of the study was 45 days. Basal recordings of blood glucose (fasting and post-prandial), lipid profile and serum insulin were taken at the time of recruitment and the second reading after forty five days. Results showed a significant improvement in all the biochemical parameters in group 1 while group 2 showed significant improvement in only few parameters, thus suggesting a beneficial effect of yoga regimen on these parameters in diabetic patients.     

Evaluation of Oxidative Stress in Type 2 Diabetes Mellitus and Follow-up Along with Vitamin E Supplementation

Increased oxidative stress is a widely accepted participant in the development and progression of diabetes and its complications. The present study has been undertaken to evaluate oxidative stress in type 2 diabetes mellitus and effect of vitamin E supplementation on oxidative stress. In all 120 subjects were enrolled in the present study, 40 subjects are age and sex matched controls. Test group comprised of clinically diagnosed (n = 80) type 2 diabetic patients. Biochemical parameters like serum MDA, nitric oxide, superoxide dismutase, erythrocyte reduced glutathione and platelet aggregation were analyzed in control and diabetic group. Test group is further categorized as Group I (n = 40) diabetics were treated by only hypoglycemic drugs and Group II (n = 40) diabetics were treated by hypoglycemic drugs with vitamin E supplementation. All above biochemical parameters were again reassessed after 3 months follow-up in both group and its values were compared with its respective baseline levels. The study shows, reduction of oxidative stress, improvement in antioxidant enzymes and endothelial dysfunction in group II, those were on treatment of hypoglycemic drugs along with vitamin E supplementation. Hence the present study may conclude that vitamin E supplementation along with hypoglycemic drugs may be beneficial to type 2 DM patients to minimize vascular complications.     

Type-2 diabetes related intermediate phenotypic traits in north Indian diabetics

Asian Indians are known to be at a higher risk of developing T2DM, but the underlying genetic factor in this population is still not well understood. T2DM is a complex genetic trait and assessment of disease related intermediate phenotypic traits is an important initial step towards any systematic genomic study. Therefore, in the present study we have assessed diabetes related intermediate phenotypic traits of insulin secretion and insulin resistance in the patients belonging to this population. The study included 157 T2DM patients of either sex ranging in age from 45–80 years and 84 non-diabetic subjects with no family history of diabetes, ranging in age from 45 to 75 years served as controls. Intermediate phenotypic traits studied were BMI, W: H ratio, fasting free fatty acid level and Insulin resistance and secretion. Diabetics were found to have significantly higher W: H ratio (p<0.001), FFA (p<0.001) and HOMA-R (p<0.001) as compared to non-diabetics. However, there was no significant difference in their BMI and HOMA-β. There was a positive correlation between FFA level and HOMA-R among diabetics, but not among controls. These findings suggest that in abdominal obesity FFA mediated insulin resistance is an important causative factor underlying T2DM in this population. Moreover, comparable HOMA-β in diabetics reflects compensatory insulin hyper secretion in these subjects. There is a need to examine relative contribution and precise nature of genetic factor in their tendency for central obesity, free fatty acidemia and insulin resistance.     

Study of Common Genetic Variant S447X in Lipoprotein Lipase and Its Association with Lipids and Lipoproteins in Type 2 Diabetic Patients

Elevated plasma triglyceride and non-esterified fatty acid concentrations may cause insulin resistance and type 2 diabetes mellitus. Lipoprotein lipase (LPL) is a rate-determining enzyme in lipid metabolism. A variant in the LPL gene has been identified which alters the penultimate amino acid Serine at 447 to a stop codon (S447X), and results in a truncated LPL molecule lacking the C-terminal dipeptide Ser–Gly. The present study was designed to evaluate the frequency of S447X variant in the LPL gene and its effect on the lipid and lipoprotein levels in type 2 diabetic subjects. The genotype frequency distributions of type 2 diabetes patients and controls were in Hardy–Weinberg equilibrium. Comparison of the genotype and allelic frequencies of S447X in subjects with type 2 diabetics compared to controls demonstrated no significant difference. In subjects with type 2 diabetics having hypertriglyceridemia (TG ≥ 150 mg/dl) compared to diabetics with TG level <150 mg/dl, significant difference in genotype frequency was found among these groups, while allelic frequency of X was significantly differed. Logistic regression analysis showed the negative association of LPL S447X variant with TG and VLDL cholesterol, while no association with total cholesterol, HDL cholesterol and LDL cholesterol was found. The lipid levels except for HDL cholesterol were found to be significantly lower in carriers for S447X than wild type in diabetes group. The decreased level of TG and TG rich lipoprotein in subjects with SNP S447X in LPL, predicts anti-atherogenic activity of carriers for S447X variant in general population as well as type 2 diabetic patients.     

Thyroid Disorders in Patients of Type 2 Diabetes Mellitus

The study was planned to assess the prevalence of thyroid disorders in type 2 diabetes in North Indian population and to correlate the serum insulin and glycosylated haemoglobin levels with thyroid hormones. It is a case control study. One hundred and twenty patients of type 2 diabetes were included in the study along with 117 adults of the same age group and normal glucose levels as controls. All blood samples were taken from subjects who fasted for at least 12 h before the blood collection. Glycosylated hemoglobin was determined by ion exchange chromatography and serum insulin and thyroid hormones were assessed through enzyme linked immunosorbent assay. Fasting blood glucose and glycosylated haemoglobin levels were significantly higher in diabetics showing a poor glucose control. Serum tri-iodothyronine values were significantly lower in diabetics. There was a significant correlation between glycosylated haemoglobin and thyroid hormones. There was no correlation between serum insulin and thyroid hormones.     

Haptoglobin Polymorphism and Association with Complications in Ghanaian Type 2 Diabetic Patients

There is scanty information on the role of genetic factors, especially those relating to haptoglobin (Hp) phenotypes in the expression of complications among diabetes mellitus patients in Ghana. In this study, we investigated whether there is any association between Hp phenotypes and diabetic complications and to determine if association of the Hp phenotypes with diabetic complications in Ghanaian diabetics differ from those in Caucasians. A total of 398 participants were randomly recruited into the study. These comprised diabetic patients numbering 290 attending a diabetes Clinic in Ghana and 108 non-diabetic controls from the same community. Analyses of the results indicate that most of the diabetics with complications were of the Hp 2–2 (35%) and Hp 2–1 (23.9%) phenotypes. Fewer diabetics were found to be of the Hp 2–1 M phenotype. The controls were mostly of Hp 1–1 and Hp 2–1 M phenotypes. The odds ratio of having complications in a diabetic with an Hp 2–2 phenotype was 18.27 times greater than that for Hp 0–0. Hp 2–2 phenotype with its poor antioxidant activity may therefore be a useful predictor for the propensity of an individual to develop diabetes complications.     

Glycosylated haemoglobin-a diagnostic tool in pregnant diabetics

Blood samples of 40 pregnant women were analysed for glycosylated haemoglobin (HbA1c) and blood sugar. The patients were followed up till delivery and their obstetric outcome was analysed in conjunction with the glycaemic profile and the level of glycosylated haemoglobin. Group I comprising the normal pregnant women showed a mean HbA1c of 6.23% at 20–40 weeks of gestation. In contrast the diabetic pregnant women (group II) at the same gestation demonstrated an HbA1c of 9.4%. Further group IIA of gestational diabetic women showed an HbA1c of 8.97% and group IIB comprising the overt diabetics had HbA1c of 9.86%. The mother who delivered a congenitally malformed child had an elevated HbA1c of 10.4% during pregnancy. Seven cases of macrosomia were reported and the mean HbA1c of their mothers at 20–40 weeks of gestation was found to be 9.91%. Six mothers delivered infants who developed respiratory distress syndrome (RDS) soon after birth and all these six had elevated HbA1c with a mean of 8.9%. Abortions were also associated with elevated HbA1c of 10.3% antenatally. One case of still birth was reported and the mother demonstrated an elevated glycosylated haemoglobin during pregnancy. An HbA1c of 10% or more was associated with abortion, still-birth, or congenitally malformed babies.     

Dyslipidemia Associated with Poor Glycemic Control in Type 2 Diabetes Mellitus and the Protective Effect of Metformin Supplementation

The nature of the dyslipidemia associated with diabetes mellitus is complex and is the major risk factor for atherosclerosis and coronary artery disease. Aim of this study was to assess the effect of glycemic control, achieved by metformin, glibenclamide and insulin, on lipid profile in type 2 diabetic patients. One hundred and sixty-five type 2 diabetes mellitus patients were classified into good glycemic control (Group I) and poor glycemic control (Group II) on the basis of their blood HbA1c values. The Group II was characterized with high serum triglyceride (190.46 ± 15.20 mg/dl), total cholesterol (175.3 ± 6.31 mg/dl) as well as high LDL-cholesterol (109.0 ± 5.88 mg/dl). Significant correlations were evident between HbA1c and dyslipidemia, particularly serum TG (r = 0.28, P < 0.05), and between HbA1c and total cholesterol (r = 0.310, P < 0.05). Better glycemic control and improved dyslipidemia were observed in patients on combination therapy of metformin plus glibenclamide.     

Serum fructosamine in a random group of adult onset diabetics of Indian subpopulation

Serum fructosamine (SFRC) was estimated using single colour reading procedure in 50 normals and 160 adult onset random diabetics. Serum fructosamine levels were observed to be 1.86±0.321 m moles/L (Range 1.0 to 2.4) and 3.44±0.671 (Range 2.0 to 5.7) in normal and diabetic subjects respectively. Serum fructosamine levels as determined by the method adapted, were found to be unaffected by a transient rise in serum glucose levels during an oral glucose tolerance test. Significantly elevated SFRC concentration was also seen in diabetic groups in spite of different combinations of antidiabetic treatment. Attempts to correlate SFRC with duration and secondary complications of diabetes did show significant elevation in all the groups irrespective of duration and complications thus indicating poor glycemic control.     

Effect of (-)epicatechin in modulating calicum-atpase activity in normal and diabetic human erythrocytes

Aqueous extract of the wood ofPterocarpus marsupium, commonly known as ‘bijasar’, is used in Indian Ayurveda system of medicine for treatment of diabetes. The active anti-diabetic principle in its aqueous extract has been found to be (-)epicatechin, a flavonoid. The present work was undertaken to study the effect of (-)epicatechin on erythrocyte membrane Ca⁺⁺-ATPase from type 2 diabetic patients. The activity of erythrocyte Ca⁺⁺-ATPase was significantly lower in type 2 diabetics.In vitro insulin treatment of erythrocyte ghosts, resulted in the increase of Ca⁺⁺-ATPase activity in diabetic patients. Treatment with (-)epicatechin (1mM) resulted in an increase in the activity of erythrocyte Ca⁺⁺-ATPase in both normal individuals and type 2 diabetic patients. The insulin like effect of (-)epicatechin on erythrocyte membrane Ca⁺⁺-ATPase in type 2 diabetics is an interesting finding. Further work is needed to elucidate the mechanism of action of (-)epicatechin on modulation of erythrocyte membrane bound enzymes.     

Assessment of glycemic potential of<Emphasis Type="Italic">Musa paradisiaca</Emphasis> stem juice

The present study reveals the effect of Musa paradisiaca stem juice on blood glucose level (BGL) of normal & diabetic rats. The dose of 500 mg/kg bodyweight produces a significant rise of 28.3% in blood glucose level after 6h of oral administration in normal rats. Whereas, in sub diabetic rats the same dose produces a rise of 16.4% in blood glucose levels within 1h during glucose tolerance test (GTT) and a rise of 16% after 4 h in fasting blood glucose levels of severe diabetic cases. These results were unexpected and important to report as other species of Musa like Musa sapientum has been reported for its hypoglycemic effect.     

Antidiabetic Effect of GII Compound Purified from Fenugreek (<Emphasis Type="Italic">Trigonella foenum graecum</Emphasis> Linn) Seeds in Diabetic Rabbits

Aim is to study the antidiabetic effect of a compound GII purified earlier from the water extract of fenugreek (Trigonella foenum graecum) seeds by Murthy and his colleagues (patented in India and USA) in diabetic rabbits. Diabetes was induced in rabbits by injecting 80 mg/kg bw of alloxan intravenously into rabiits. Rabbits were subdivided into subdiabetic [fasting blood sugar (FBG) up to 120 mg/dl with abnormal glucose tolerance in glucose tolerance test (GTT)], moderately diabetic (FBG below 250 mg/dl) and severely diabetic (FBG above 250 mg/dl). Blood glucose and glycosylated hemoglobin (HbA1C) were estimated by procedures in the kits of Stangen Immunodiagnostics, Mumbai using, respectively, glucose oxidase method and absorbance at 415 nm. Serum insulin was estimated by the ELISA method as described in the kit of Boehringer Mannheim Immunodiagnostics, Mumbai, India. GII was found to improve blood glucose utilization in GTT and reduced FBG and HbA1C. In the present communication detailed studies were carried out with GII in the subdiabetic, moderately diabetic and severely diabetic rabbits. GII at a dose of 50 mg/kg bw per day brought down the elevated FBG levels in the untreated subdiabetic (FBG 96.6 ± 7 mg/dl), moderately diabetic (150.1 ± 14 mg/dl) and severely diabetic rabbits (427 ± 46 mg/dl) to normal in 12, 15 and 28 days of treatment. It improved serum HbA1C and insulin levels also in these rabbits. Intermittent therapy once a week for 6 weeks with GII at the same dose brought down the FBG values to normal in the subdiabetic (FBG 96.0 ± 2 mg/dl) and in the moderately diabetic rabbits to 133.0 ± 12 mg/dl. After stopping therapy of the subdiabetic and moderately diabetic rabbits whose FBG values came to normal after treatment with GII 50 mg/kg bw, the values remained normal for 1 week and showed a tendency to increase only after 15 days. If these animal studies are applicable to humans these results indicate that a diabetic person need not take GII daily when once the FBG value comes to normal or near to normal. Patients might be able to take GII only when the FBG value shows tendency to increase. So, intermittent therapy is possible with the potent product GII of the fenugreek seeds which is of a great advantage.     

Insulin or sulfonylurea treatments of the diabetics differentially affect erythrocyte membrane and serum enzymes and extent of protein glycosylation

Erythrocyte membrane protein glycosylation increase by 3.4 fold in diabetes. Insulin or sulfonylurea treatment did not reduce the extent of glycosylation. The serum protein glycosylation was comparable in all the groups including control. Erythrocyte membrane Na⁺,K⁺-ATPase activity decreased in the diabetics; only insulin treatment partly restored the activity. Erythrocyte membrane acetylcholinesterase activity decreased only in the sulfonylurea treated group. Serum butyrylcholinesterase activity was relatively low in the diabetic and insulin treated diabetic groups. The Km and Vmax of the two components of Na⁺,K⁺-ATPase from erythrocyte membranes were differently affected in the diabetic and the two treatment groups. The Vmax of acetylcholinesterase decreased only in the sulfonylurea treated group. Diabetic states resulted in decreased Vmax of components I and II of serum butyrylcholinesterase. In insulin-treated diabetics, component II was absent. Sulfonylurea group resembled diabetics.In vitro incubation with insulin differentially affected the Na⁺,K⁺-ATPase and serum butyrylcholinesterase activities.     

Use of glycated hemoglobin (HbA<Subscript>1C</Subscript>) and impaired glucose tolerance in the screening of undiagnosed diabetes in the Malaysian population

Although HbA_1C is widely accepted as a useful index of mean blood glucose in type 2 diabetic patients its usefulness as screening test for diabetes has been controversial. The present study was undertaken to determine whether the level of HbA_1C predicted diabetes in a prediabetic group of subjects. Plasma lipids, oral glucose tolerance, HbA_1C was determined in 90 normal control subjects, 57 offspring of one type 2 diabetes mellitus parent and 11 diagnosed type 2 diabetes mellitus individuals. The mean age of participants was 44.5 yrs (not significantly different amongst the three groups) and the mean body mass index was 26.8 (not significantly different amongst the three groups). Two hours after a 75 g glucose challenge, the offspring had a significantly higher plasma glucose level (mean = 7.1 mmol/L, p value = 0.002) than the normals. Similarly the HbA_1C values were higher in the offspring than in the normals (mean = 5.78%, p value = 0.016). Besides the significantly higher values for oral glucose tolerance test and HbA_1C, the diabetics also were significantly higher for triglycerides (mean = 2.25mmol/L), total cholesterol (mean = 6.24mmol/L) and systolic blood pressure (mean = 138.45mm Hg) than the offspring (P value = 0.031, 0.006, 0.010) and the normals (P value = 0.026, 0.018, 0.002) respectively. The mean values of diastolic blood pressure, LDL cholesterol and HDL cholesterol were not significantly different amongst the three groups.     

Comparison between erythrocyte hemoglobin and spectrin glycosylation and role of oxidative stress in type-2 diabetes mellitus

New findings on organization of blood cell cytoskeleton represent an exciting aspect of modem cell biology and hematology, which is an interesting investigation to study diabetes. The present study was undertaken in 150 subjects. Out of these, 30 subjects were controls (Group I) and 30 were type-2 diabetics without any complication (Group II), while remaining 90 subjects were type-2 diabetics with complication (Group III). We determined erythrocyte spectrin and hemoglobin glycosylation and also estimated plasma lipid peroxide, nitric oxide and erythrocyte glutathione peroxidase activity to assess the status of oxidative stress. There was a significant increase in spectrin (P<0.001) and hemoglobin (P<0.001) glycosylation in Group II and III as compared to Group I and spectrin glycosylation was nearly three times more as compared to hemoglobin, whereas plasma levels of lipid peroxide (P<0.001) as well as nitric oxide (P<0.001) were found to be significantly increased and GPx activity (P<0.001) was significantly decreased in Group II and III as compared to Group I. However, it was also observed that spectrin (P>0.05) and hemoglobin (P>0.05) glycosylation was not significantly different in Group II and III. In contrast, there was significant rise in lipid peroxide (P<0.001), nitric oxide (P<0.001) and fall in GPx activity (P<0.001) in Group III when compared to Group II. Increased erythrocyte protein glycosylation and oxidative stress is clearly evident from our study. However, to understand the exact interplay between these two mechanisms, further studies are required.     

Serum Lp(a) in diabetics with and without evidence of clinical nephropathy—A preliminary study

Type 2 diabetes is associated with a marked increase in the risk of coronary artery disease. Dyslipidaemia is believed to be a major cause of this increased risk. Recently, elevated levels of lipoprotein (a), Lp(a), have been reported to be associated with an increased risk. However there is very little data regarding Lp(a) concentrations and type 2 diabetes from India. The objective of the study was to assess serum Lp(a) levels in type 2 diabetics with and with out evidence of clinical nephropathy. We estimated serum Lp(a) levels in 30 control subjects, 30 diabetics without evidence of clinical nephropathy and 30 diabetics with evidence of clinical nephropathy. Statistical analysis showed that Lp(a) levels were increased in diabetic patients with nephropathy (mean 46.3±17.6 mg/dl). The Lp(a) levels however did not differ significantly between control (mean 20.2±15.9 mg/dl) and diabetics without nephropathy (mean 22.6±13.1mg/dl). Thus diabetes per se seems to have little or no influence on serum Lp(a) levels, however elevated levels were seen in patients with nephropathy.     

Effect of insulin on serum lipids in relation to nutritional status in diabetics

Serum levels of cholesterol, triglyceride, free fatty acid (FFA) and high density lipoprotein (HDL) cholesterol were studied in 10 undernourished and 10 better nourished diabetic patients at different periods of insulin treatment and in non-diabetic controls. Serum concentrations of cholesterol, triglyceride and FFA were significantly higher in untreated diabetic patients than in control but the elevated lipid levels gradually shifted towards normal on insulin treatment. The HDL cholesterol, on the other hand, was significantly lower in untreated diabetic subjects than those in controls and the HDL cholesterol also gradually modified on insulin therapy. However, the improvement of all the lipid parameters on insulin treatment was somewhat delayed in undernourished compared to those of better nourished diabetics. These results, therefore, suggest that malnutrition interferes with the serum lipid improvement in diabetics on insulin treatment and may make them more prone to develop vascular complications.     

Session - 5 December 18, 2007 AACC Symposium

The prevalence of abnormal thyroid hormone levels in diabetes mellitus in Nigeria is not well described. To determine the incidence of abnormal thyroid hormone levels in diabetics in Calabar, Nigeria, fasting blood samples from 161 diabetic subjects and 105 non-diabetic controls were analysed. Free thyroxine (FT), thyroid stimulating hormone (TSH), total triiodothyronine (T₃) and total thyroxine (T₄) kits obtained from Biomerica Inc. of USA were used for the analysis. TSH levels (1.80±1.62) in diabetics were significantly lower (p=0.016) than the level in non-diabetic controls (2.34±1.24). Male diabetics had lower (p<0.05) levels of TSH (1.192±0.68 miu/ml) than diabetic females (1.90±1.70 mlu/mt). The level of T₃ in diabetic males (125±97ng/ml) was higher than the level in females (98±75ng/dl). TSH (F=2.74, p=0.049), T₄(F=56.87, p=0.001), T₃(F=56.44, P=0.001) in diabetics and FT₄ (F=5.74, p=0.002) in controls showed significant variation with the ages of the subjects. Out of 161 diabetics subjects studies 26.6% had low plasma thyroid hormone levels (FT₄>2.01 ng/dl). This study has shown a high incidence (46.5%) of abnormal thyroid hormone levels among the diabetics in Nigeria (hypothyroidism 26.6%, hyperthyroidism, 19.9%). The prevalence of hypothyroidism was higher in women (16.8%) than in men (9.9%), while hyperthyroidism was higher in males (11%) than in females (8%). This study has defined thyroid function status of diabetics in Calabar, Nigeria probably the first of such work in Africa.     

Abdominal Obesity Associated with Elevated Serum Butyrylcholinesterase Activity,Insulin Resistance and Reduced High Density Lipoprotein-Cholesterol Levels

Abdominal obesity (AO) has a strong correlation with cardiovascular disease and has been linked to Alzheimer’s disease and type 2 diabetes. We investigated the association between AO and elevated serum butyrylcholinesterase (BChE) activity, insulin resistance and the serum lipid profile, including triglyceride (TG), HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C) levels in AO and non-AO women subjects. A total of 500 AO subjects (age 49.1 ± 10.5 years), and 142 non-AO women subjects (age 49.9 ± 11.9 years) were enrolled for the general biochemistry tests, serum BChE, fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR). Body mass index, waist circumference, Blood pressure (BP), plasma glucose (Glu), triglyceride (TG), BChE, insulin, HOMA-IR were significantly higher and HDL-C levels were significantly lower in AO subjects (p < 0.05). Waist circumference was significantly correlated with BP, Glu, TG, BChE, insulin and HOMA-IR in AO subjects. Multiple logistic regression demonstrated that AO was associated with elevated BChE, HOMA-IR, hypertension and reduced HDL-C after adjusting for these variables. AO is associated with elevated BChE, insulin resistance, HT and reduced HDL-C. These may predict the development of type 2 diabetes mellitus and may be associated with cognitive disorder in the future, both are mediated through insulin resistance.     

血镁与2型糖尿病视网膜病变的相关研究

为了探讨血镁在糖尿病视网膜病变发生中的作用及糖尿病视网膜病变的相关危险因素，测定了30例正常对照组，30例糖尿病无视网膜病变级（NDR组），30例糖尿病合并视网膜病变组（DR组）病人血清镁浓度，并对糖尿病病人行空腹血糖、糖化血红蛋白（HbAlc）、尿微量白蛋白排泄量的测定，记录病程，行眼底检查，结果发现，与正常相比较，血镁降低在NDR组P＜0．05，DR组P＜0．01。NDR组与DR组比较血镁降低亦有显著性意义（P＜0．01），且两组比较病程、空腹血糖、糖化血红蛋白和尿白蛋白排泄是均有显著性差异（P＜0．01）。作者认为糖尿病病人有缺镁的倾向，且糖尿病视网膜病变者的血镁比糖尿病无视网膜病变的患者更低，低镁与病程、空腹血糖、糖化血红蛋白、尿白蛋白排量一样，是糖尿病视网膜病变的危险因素。