Prevalence and Risk Factors for Undiagnosed Glucose Intolerance Status in Apparently Healthy Young Adults Aged <40 Years: The Korean National Health and Nutrition Examination Survey 2014-2017

Background: Early-onset diabetes results in longer lifetime hyperglycemic exposure that consequently leads to earlier chronic diabetes complications and premature death. The aim of this study was to quantify the prevalence and risk factors of undiagnosed diabetes and undiagnosed prediabetes in apparently healthy young adults aged <40 years. Methods: This study used data from the Korean National Health and Nutrition Examination Survey, a cross-sectional, nationally representative survey conducted by the Korean Ministry of Health and Welfare from 2014 to 2017. A total of 4442 apparently healthy young adults enrolled in this study. Multivariate logistic regression analyses were conducted separately to evaluate associated risk factors with undiagnosed diabetes and undiagnosed prediabetes in groups stratified by sex. Results: The prevalence of undiagnosed diabetes and undiagnosed prediabetes was 1.2% and 25.0%, respectively. Obesity (body mass index ≥ 30.0 kg/m²) was a significant risk factor of undiagnosed diabetes regardless of sex (men, odds ratio (OR): 9.808, 95% confidence interval (CI): 1.619–59.412; women, OR: 7.719, 95% CI: 1.332–44.747). Family history of diabetes was significantly associated with undiagnosed diabetes (OR: 3.407, 95% CI: 1.224–9.481) in women only. Increased age, obesity status, and family history of diabetes were significant risk factors for undiagnosed prediabetes. Alcohol consumption was found to be negatively associated with undiagnosed prediabetes in women. Conclusions: Increased attention and implementation of precise strategies for identifying young adults at high risk for undiagnosed diabetes would allow for increased wellbeing as well as reduced healthcare burdens associated with diabetes.

Impact of Parity on Body Size Phenotype in Postmenopausal Women: KNHANES 2010-2012

CONTEXT

Parity has been implicated in many health consequences for women in later life.

OBJECTIVE

To determine whether there is an association between parity and body size phenotypes in postmenopausal women.

DESIGN AND PARTICIPANTS

This study was based on data from the Korean National Health and Nutrition Examination Survey, conducted during 2010-2012. Of the 25 534 participants, data from 3347 postmenopausal women were included in the analysis.

RESULTS

In analyses stratified by the metabolically abnormal obese (MAO) and metabolically healthy and normal weight phenotypes, women with parities of 3-4 births or more than or equal to 5 births were significantly associated with the MAO phenotype (odds ratio [OR] 1.396 [95% confidence interval (CI) 1.077-1.810] and OR 1.978 [1.392-2.811], respectively) compared with those with a parity of 1-2 births after adjusting for age, sociodemographic factors, lifestyle behaviors, and reproductive factors. A similar significant association of parity with the MAO phenotype was also found when we analyzed the parity number as a continuous variable in a comparison of the MAO and metabolically abnormal but normal weight phenotypes (OR 1.116 [1.012-1.232]). In grouping of the MAO and metabolically healthy but obese phenotypes, women who had experienced a parity of 3-4 births or more than or equal to 5 births were significantly associated with the MAO phenotype (OR 1.459 [1.025-2.076] and OR 1.989 [1.211-3.265], respectively) after adjustment for the above covariates.

CONCLUSIONS

Parity influenced the body size phenotype in postmenopausal women, and higher parity was independently associated with a higher risk of the MAO phenotype in postmenopausal women.

Urinary Albumin Excretion Reflects Cardiovascular Risk in Postmenopausal Women without Diabetes: The 2011 to 2013 Korean National Health and Nutrition Examination Survey

BACKGROUND

The objective of the current study was to determine whether there was an association between urinary albumin excretion and cardiovascular disease (CVD) risk by estimating the Framingham Risk Score (FRS) in postmenopausal women without diabetes.

METHODS

This study was based on data from the Korea National Health and Nutrition Examination Survey, which was conducted by the Korean Ministry of Health and Welfare in 2011 to 2013. Data on 2,316 postmenopausal women from a total of 24,594 participants was included in the analysis.

RESULTS

The mean FRS was significantly different in each of the urinary albumin to creatinine ratio (UACR) subgroups, and it increased with UACR. The FRS was 12.69±0.12 in the optimal group, 14.30±0.19 in the intermediate normal group, 14.62±0.26 in the high normal group, and 15.86±0.36 in the microalbuminuria group. After fully adjusting for potential confounding factors, high normal levels and microalbuminuria were significantly associated with the highest tertile of FRS ([odds ratio (OR), 1.642; 95% confidence interval (CI), 1.124 to 2.400] and [OR, 3.385; 95% CI, 2.088 to 5.488], respectively) compared with the optimal subgroup. High normal levels and microalbuminuria were also significantly associated with a ≥10% 10-year risk of CVD ([OR, 1.853; 95% CI, 1.122 to 3.060] and [OR, 2.831; 95% CI, 1.327 to 6.037], respectively) after adjusting for potential confounding covariates.

CONCLUSION

Urinary albumin excretion reflects CVD risk in postmenopausal women without diabetes, and high normal levels and microalbuminuria were independently associated with a higher risk of CVD.

Comparison of Vildagliptin and Pioglitazone in Korean Patients with Type 2 Diabetes Inadequately Controlled with Metformin

BACKGROUND

We compared the efficacies of vildagliptin (50 mg twice daily) relative to pioglitazone (15 mg once daily) as an add-on treatment to metformin for reducing glycosylated hemoglobin (HbA1c) levels in Korean patients with type 2 diabetes.

METHODS

The present study was a multicenter, randomized, active-controlled investigation comparing the effects of vildagliptin and pioglitazone in Korean patients receiving a stable dose of metformin but exhibiting inadequate glycemic control. Each patient underwent a 16-week treatment period with either vildagliptin or pioglitazone as an add-on treatment to metformin.

RESULTS

The mean changes in HbA1c levels from baseline were -0.94% in the vildagliptin group and -0.6% in the pioglitazone group and the difference between the treatments was below the non-inferiority margin of 0.3%. The mean changes in postprandial plasma glucose (PPG) levels were -60.2 mg/dL in the vildagliptin group and -38.2 mg/dL in the pioglitazone group and these values significantly differed (P=0.040). There were significant decreases in the levels of total, low density lipoprotein, high density lipoprotein (HDL), and non-HDL cholesterol in the vildagliptin group but increases in the pioglitazone group. The mean change in body weight was -0.07 kg in the vildagliptin group and 0.69 kg in the pioglitazone group, which were also significantly different (P=0.002).

CONCLUSION

As an add-on to metformin, the efficacy of vildagliptin for the improvement of glycemic control is not inferior to that of pioglitazone in Korean patients with type 2 diabetes. In addition, add-on treatment with vildagliptin had beneficial effects on PPG levels, lipid profiles, and body weight compared to pioglitazone.

Impact of age at first childbirth on glucose tolerance status in postmenopausal women: the 2008-2011 Korean National Health and Nutrition Examination Survey

OBJECTIVE

The objective of the current study was to determine whether there was an association between age at first childbirth and glucose tolerance status in postmenopausal women.

RESEARCH DESIGN AND METHODS

This study was based on the data from the Korean National Health and Nutrition Examination Survey, conducted by the Korean Ministry of Health and Welfare from 2008-2011. Of 37,753 participants, data for 4,965 postmenopausal women were included in the analysis. Subjects were subdivided according to the age at first childbirth as follows: ≤19, 20-24, 25-29, and ≥30 years. Multivariate logistic regression analyses were used to identify whether there was an independent association between age at first childbirth and glucose tolerance status by adjusting for potential confounding factors.

RESULTS

The prevalence of impaired fasting glucose (IFG) and diabetes was 21.8% (1.066 of 4.965) and 15.3% (774 of 4,965), respectively. Diabetes prevalence differed significantly between the subgroups and was higher with earlier age at first childbirth: it was 10.9% in subjects aged ≥30 years and 23.8% in subjects aged ≤19 years at first childbirth. After fully adjusting for potential confounding factors, including lifestyle, sociodemographic factors, known diabetes risk factors, and reproductive factors, age at first childbirth ≤19 years was significantly associated with diabetes (odds ratio 1.492 [95% CI 1.005-2.215]). No significant associations were found between age at first childbirth and IFG.

CONCLUSIONS

Age at first childbirth influenced diabetes risk in postmenopausal women, and adolescent pregnancy was independently associated with a higher risk of diabetes in postmenopausal women.

Clinical marker of platelet hyperreactivity in diabetes mellitus

Atherothrombotic complications are important causes of morbidity and mortality in diabetic patients. Diabetes has been considered to be a prothrombotic status. Several factors contribute to the prothrombotic condition, such as increasing coagulation, impaired fibrinolysis, endothelial dysfunction, and platelet hyperreactivity. Among the factors that contribute to the prothrombotic status in diabetes, altered platelet function plays a crucial role. Although understanding platelet function abnormalities in diabetes still remains as a challenge, more attention should be focused on platelet function for effective management and the prediction of atherothrombotic events in diabetic patients. This review will provide an overview on the current status of knowledge of platelet function abnormalities and clinical marker of platelet hyperreactivity in patients with diabetes.

Hemoglobin a1c is positively correlated with framingham risk score in older, apparently healthy nondiabetic korean adults

BACKGROUND

Several studies have suggested that elevated levels of hemoglobin A1c (HbA1c) are associated with cardiovascular disease (CVD) in nondiabetic individuals. However, it is unclear whether HbA1c levels can serve as a simple screening marker for increased CVD risk in nondiabetic individuals. Our objective was to evaluate the relationship between HbA1c levels and CVD risk using the Framingham risk score (FRS) in older, apparently healthy nondiabetic Korean adults.

METHODS

We retrospectively studied 2,879 Korean adults between the ages of 40 and 79 who underwent voluntary health check-ups at the Health Promotion Center of our hospital from July 2009 to June 2011. Subjects were subdivided based on their HbA1c levels into four groups: tertiles within the HbA1c normal tolerance range and a group for subjects with an increased risk for diabetes (IRD).

RESULTS

The mean FRS for the upper tertile (9.6±3.8) group was significantly higher than that of the middle tertile (8.4±4.0) and lower tertile (7.6±3.8) groups. In addition, FRS was highest in the IRD group (10.5±3.7). Multiple linear regression analysis demonstrated that HbA1c levels exhibited a significant positive correlation with FRS when adjusted for confounding variables in all subjects (β±standard error [SE], 0.018±0.002; R (2), 0.131), women (β±SE, 0.023±0.003; R (2), 0.170), and men (β±SE, 0.016±0.004; R (2), 0.109).

CONCLUSION

HbA1c levels were positively correlated with FRS in older, apparently healthy nondiabetic Korean adults. We propose that HbA1c levels may reflect CVD risk in nondiabetic individuals.

Thyrotoxic periodic paralysis with Graves' disease leading to the discovery of a hidden nonclassic 11β hydroxylase deficiency

11β hydroxylase deficiency (OHD) is one of the main causes of congenital adrenal hyperplasia. There have been only a few reported cases of nonclassic 11β OHD, a milder form of the disease. It is difficult to detect occult nonclassic 11β OHD because patients present with no or mild symptoms. We herein present a case of thyrotoxic periodic paralysis (TPP) with Graves' disease leading to the discovery of a hidden nonclassic 11β OHD. In this case, increased levels of thyroid hormone seem to have induced symptoms of occult nonclassic 11β OHD and aggravated TPP.

The mean platelet volume is positively correlated with serum thyrotropin concentrations in a population of healthy subjects and subjects with unsuspected subclinical hypothyroidism

BACKGROUND

A possible prothrombotic effect of elevated thyrotropin (TSH) has been suggested. The mean platelet volume (MPV), which is used to measure the platelet size, can reflect platelet activity. Although limited and inconsistent data regarding the effects of thyroid function on the MPV are available from small-scale case-control studies, no study has been based on a general population, particularly in euthyroid states. The objective of the present study was to determine whether there is an association between the MPV and serum TSH concentrations in an apparently healthy Korean population without overt thyroid disease, but including subjects with unsuspected subclinical hypothyroidism (SCH).

METHODS

We retrospectively studied 6893 asymptomatic Korean adults who were 20 years of age or older and who underwent voluntary regular health check-ups at the Health Promotion Center of Chosun University Hospital. The subjects who met the inclusion and exclusion criteria were subdivided into four groups, such as tertile groups for the TSH reference range and an SCH (TSH ≥4 μIU/mL with a normal free T4 concentration) group according to the TSH level. We compared the mean values of the MPVs among the groups. Multivariate logistic regression analyses were used to identify associations between the highest tertile of the MPV and the TSH subgroups.

RESULTS

The mean level of the MPV in all study subjects was 8.12±0.75 femtoliters (fL), and the mean value of the MPV was significantly different in each group. The mean MPV in SCH was significantly higher compared with those of the first tertile (T1) and second tertile (T2). Moreover, the mean MPV increased statistical significantly by increasing tertiles of the TSH concentration and was highest in SCH (T1, 8.08±0.81 fL; T2, 8.09±0.62 fL; T3, 8.13±0.77 fL; SCH, 8.21±0.81 fL; p for trend=0.012). After adjusting for risk factors associated with increasing MPVs and platelet counts, SCH was independently associated with the highest tertile of the MPV (all subjects, odds radio (OR) 1.58 [95% confidence interval (CI) 1.19-2.09]; men, OR 1.70 [CI 1.10-2.64]; women, OR 1.55 [CI 1.06-2.26]).

CONCLUSIONS

The MPV was positively correlated with the TSH level. SCH is an independently associated factor with the highest tertile of MPV in a general Korean population. We propose that the MPV may contribute to the prothrombotic condition that is associated with SCH and perhaps even in putative euthyroid states where the TSH level is the higher part of the normal range.

Discordance between HbA1c and fasting plasma glucose criteria for diabetes screening is associated with obesity and old age in Korean individuals

We evaluated the agreement between HbA1c- and FPG-based criteria for screening of diabetes in an asymptomatic Korean population and identified independent factors associated with discordance. The discordance between the two diabetic criteria was significantly associated with obesity and older age.

Symptomatic calcification of a thyroid lobe and surrounding tissue after radioactive iodine treatment to ablate the lobe

BACKGROUND

Fine-needle aspiration diagnosis of follicular carcinoma presents a dilemma because malignancy is confirmed when vascular or capsular invasion is present. Completion thyroidectomy may be necessary when the diagnosis of follicular carcinoma is made following hemithyroidectomy. Ablation of the remaining lobe with radioactive iodine has been used as an alternative to completion thyroidectomy. Here we report an unusual apparent complication of this treatment.

PATIENT FINDINGS

A 51-year-old woman presented in September 24, 2009 with a stony, hard calcification of left thyroid gland. She complained of recent progressive hoarsening of her voice. Her medical history was positive for a subtotal thyroidectomy on September 6, 1993. Histologic analysis identified follicular carcinoma. Two months postoperatively, the remaining tissue was ablated with (131)I (150 mCi) as an alternative to completion thyroidectomy. We performed computed tomography of the neck, which demonstrated 1.6  x 1.9 x  2.2 cm dense speculated calcification of the entire left residual thyroid gland. The calcification infiltrated the trachea wall. Completion thyroidectomy, including resection of the calcification, was performed. Histologic examination revealed dystrophic calcification.

CONCLUSION

We report an unusual replacement of the thyroid remnant with calcification that developed over a period of 16 years following radioactive iodine lobe ablation as an alternative to completion thyroidectomy for thyroid follicular carcinoma. To our knowledge, this is the first such case in the English language literature.

A multicenter, randomized, placebo-controlled, double-blind phase II trial evaluating the optimal dose, efficacy and safety of LC 15-0444 in patients with type 2 diabetes

AIM

The objective of this study was to evaluate the optimal dose, efficacy and safety of a novel dipeptidyl peptidase-4 (DPP-IV) inhibitor, LC15-0444, in Korean subjects with type 2 diabetes mellitus treated by diet and exercise.

METHODS

This study was a double-blind, randomized, multicenter and parallel-group, dose-range finding study. We enrolled 145 patients (91 men and 54 women) with a median age of 53 years and a median body mass index of 25.1 kg/m(2) . The median baseline fasting plasma glucose (FPG) was 8.1 mmol/l, the median HbA1c was 7.9% and the median time since the diagnosis of diabetes was 3 years. After 2 weeks of an exercise/diet programme followed by 2 weeks of a placebo period, the subjects were randomized to one of the four following groups for a 12-week active treatment period: placebo and 50, 100 or 200 mg of LC15-0444.

RESULTS

All three doses of LC15-0444 significantly reduced the HbA1c from baseline compared to the placebo group (-0.06 vs. -0.98, -0.74 and -0.78% in the placebo and 50, 100 and 200 mg groups, respectively), without a significant difference between the doses. Subjects with a higher baseline HbA1c (≥8.5%) had a greater reduction in HbA1c. Insulin secretory function, as assessed using homeostasis model assessment-beta cell, C-peptide and the insulinogenic index, improved significantly with LC15-0444 treatment. Insulin sensitivity, as assessed using homeostasis model assessment-insulin resistance, also improved significantly after 12 weeks of treatment. The 50 and 200 mg groups had significantly reduced total cholesterol and low-density lipoprotein cholesterol levels at 12 weeks compared to the placebo group. No dosage of LC15-0444 affected weight or waist circumference. The incidences of adverse events were similar in all study subjects.

CONCLUSIONS

LC15-0444 monotherapy (50 mg for 12 weeks) improved the HbA1c, FPG level, oral glucose tolerance test results, β-cell function and insulin sensitivity measures, and was well tolerated in Korean subjects with type 2 diabetes.

Pharmacokinetic changes of acebutolol after oral administration in rabbits with diabetes mellitus induced by alloxan

Because physiological changes that potentially alter pharmacokinetics occurs in diabetes mellitus patients, pharamacokinetics of drugs used in the treatment of hypertension was studied using acebutolol as a model anti-hypertensive drug. Thus, the pharmacokinetics of acebutolol was investigated after oral administration of acebutolol (15 mg/kg) to control rabbits and rabbits with acute or chronic diabetes mellitus induced by alloxan. Kidney and liver functions were documented for acute and chronic diabetes mellitus groups based on plasma chemistry data. After oral administration of acebutolol to acute and chronic groups, the plasma concentrations appeared higher; As a result, area under the plasma concentration-time curve from time zero to time infinity10575 and 8668 microg x h/mL for acute and chronic group, respectively. In comparison, the area was apparently smaller in the control group (i.e., 7132 microg x h/mL). The half-life in acute groups was significantly prolonged 8.45 h compared with the half-life in the control group (i.e., 6.30 h). Alteration in acebutolol pharmacokinetics was more pronounced in the acute group as evidenced by the significantly higher values the area under the plasma concentration time curve, absorption rate constant and maximum plasma concentration compared with chronic or control group. Therefore, these observations indicate that acebutolol pharmacokinetics may be affected in patients with diabetes mellitus, especially in the early stage of the disease.

Pharmacokinetics of tolbutamide after oral administration in rabbits with folate-induced renal failure

The pharmacokinetic changes of tolbutamide were studied after oral administration to normal rabbits and mild and medium folate-induced renal failure rabbits. Tolbutmide 50 mg/kg was orally administered to the rabbits. The plasma concentrations of tolbutamide were significantly increased (p<0.05) at 9 to 24 hr in mild and medium folate-induced renal failure rabbits compared with those in normal rabbits. Therefore, the area under the plasma concentration-time curves (AUC) was significantly higher (p<0.05 and p<0.01 respectively) in mild and medium folate-induced renal failure rabbits (2906 microg/ml x hr and 4074 microg/ml x hr) than that in normal rabbits (2295 microg/ml x hr). The cumulative urinary excretion of tolbutamide was significantly decreased (p<0.05) in medium folate-induced renal failure rabbits (3.3 mg) compared with the normal rabbits (5.9 mg). The elimination rate constant (Kel) of tolbutamide was significantly slower in medium folate-induced renal failure rabbits (0.027 hr(-1)) than that in normal rabbits(0.044 hr(-1)). The terminal half-life of tolbutamide in medium folate-induced renal failure rabbits (25.5 hr) was significantly longer (p<0.01) than in normal rabbits (15.7 hr). These results could be considered as possibly due to inhibited excretion of tolbutamide metabolites or retarded metabolism of tolbutamide.

Cellular and molecular mechanism for Kilham rat virus-induced autoimmune diabetes in DR-BB rats

Kilham rat virus (KRV) causes autoimmune diabetes in diabetes-resistant BioBreeding (DR-BB) rats; however, the mechanism by which KRV induces autoimmune diabetes without the direct infection of beta cells is not well understood. We first asked whether molecular mimicry, such as a common epitope between a KRV-specific peptide and a beta cell autoantigen, is involved in the initiation of KRV-induced autoimmune diabetes in DR-BB rats. We found that KRV peptide-specific T cells generated in DR-BB rats infected with recombinant vaccinia virus expressing KRV-specific structural and nonstructural proteins could not induce diabetes, indicating that molecular mimicry is not the mechanism by which KRV induces autoimmune diabetes. Alternatively, we asked whether KRV infection of DR-BB rats could disrupt the finely tuned immune balance and activate autoreactive T cells that are cytotoxic to beta cells, resulting in T cell-mediated autoimmune diabetes. We found that both Th1-like CD45RC+CD4+ and cytotoxic CD8+ T cells were up-regulated, whereas Th2-like CD45RC-CD4+ T cells were down-regulated, and that isolated and activated CD45RC+CD4+ and CD8+ T cells from KRV-infected DR-BB rats induced autoimmune diabetes in young diabetes-prone BioBreeding (DP-BB) rats. We conclude that KRV-induced autoimmune diabetes in DR-BB rats is not due to molecular mimicry, but is due to a breakdown of the finely tuned immune balance of Th1-like CD45RC+CD4+ and Th2-like CD45RC-CD4+ T cells, resulting in the selective activation of beta cell-cytotoxic effector T cells.

Impaired homeostatic mechanism of potassium handling after acute oral potassium load in diabetes mellitus

Chronic stable diabetic patients (n = 6) were compared with healthy control subjects (n = 5) after acute oral intake of 50 mEq of potassium chloride (KCl) to investigate for possible derangements of homeostatic responses for acute term (3 hrs) to acute potassium load. Plasma renin activity (PRA), plasma aldosterone (PA), and transtubular potassium concentration gradient (TTKG) known as a useful semiquantative index of distal nephron potassium secretion were measured. All the baseline parameters were comparable between diabetic and non-diabetic subjects except for significantly reduced creatinine clearance in diabetics (mean +/- SEM, 105 +/- 4 vs. 85 +/- 5 ml/min, p < 0.05). Following acute oral KCl load, the peak increases of serum potassium changes from basal levels were noted at 2 hours in both groups, but were higher in diabetic subjects (mean +/- SEM, 0.42 +/- 0.06 vs. 0.62 +/- 0.09 mEq/L). Also, 4 out of 6 diabetic subjects but none of the control subjects at 2 hours after oral KCl load became hyperkalemic ( > 5.0 mEq/L). PRA did not show any significant changes, whereas PA was increased simultaneously with increments in serum potassium in both groups, with blunted increases in the diabetics. However, TTKG was increased prominently in control subjects (8.18 from 4.98), but only slightly in diabetic subjects (4.55 from 4.18), with statistical difference between the two groups (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Heterogeneous changes of serum potassium levels in NIDDM patients on oral glucose load

Ten noninsulin dependent diabetic patients (NIDDM) without baseline hyperkalemia and with normal aldosterone levels when given 100 g of glucose orally revealed heterogeneous responses in serum potassium changes. Six diabetics had paradoxical increases in serum potassium levels averaged 0.44 mEq/L (range, 0.1 to 1.1 mEq/L) and were accompanied by increases in plasma aldosterone levels. On the contrary, four other noninsulin dependent diabetics and four nondiabetic control subjects had gradual decreases in serum potassium levels with simultaneous decreases in plasma aldosterone levels. These rises and falls in serum potassium concentrations coincided with changes in serum osmolality related mostly to the degree of increases in serum glucose following oral glucose administration. pH of venous blood didn't show any relevant and significant changes with changes of serum potassium levels following oral glucose load. This finding suggests that osmotic mechanisms with various degree of well known abnormal insulin secretion and resistance to insulin action in target tissues in NIDDM patients may account for these heterogeneous responses in serum potassium changes after glucose load, and normal aldosterone levels may not be sufficient to prevent glucose induced increases in serum potassium in NIDDM patients.

Subepidermal capillary basement membrane thickness of the skin obtained by punch biopsy in patients with non insulin dependent diabetes mellitus

Thickening and proliferation of the capillary basement membrane is a generalized phenomenon in diabetes mellitus and has been described in many organs including the heart, kidney, pancreas, retina etc. While such changes are specific, it is difficult to obtain specimens from those organs. Tissue samples were obtained from the medial surface of the thigh of 33 diabetics and 4 healthy controls by means of punch biopsy. Measurements carried out by normogram obtained from electron microscopic pictures. HbA1c values were also determined at time of muscle biopsy. 1. The HbA1c values are higher in diabetics than in the control group (p<0.01). 2. The subepidermal capillary basement membrane thickness of the diabetics: 30% of the 5’th decade population, 53.9% of the 6’th decade population and 83.3% of the 7’th decade population was greater than 3,000 A°. Whereas that of the controls was less than 3,000 A°. 3. The subepidermal capillary basement membrane thickness was not significantly increased with the duration of the disease. 4. In cases of greater subepidermal capillary besement membrane thickness, HbA1c showed a significant increase. (p<0.01).