Two risk score models for predicting incident Type 2 diabetes in Japan

AIMS

Risk scoring methods are effective for identifying persons at high risk of Type 2 diabetes mellitus, but such approaches have not yet been established in Japan.

METHODS

A total of 1935 subjects of a derivation cohort were followed up for 14 years from 1988 and 1147 subjects of a validation cohort independent of the derivation cohort were followed up for 5 years from 2002. Risk scores were estimated based on the coefficients (β) of Cox proportional hazards model in the derivation cohort and were verified in the validation cohort.

RESULTS

In the derivation cohort, the non-invasive risk model was established using significant risk factors; namely, age, sex, family history of diabetes, abdominal circumference, body mass index, hypertension, regular exercise and current smoking. We also created another scoring risk model by adding fasting plasma glucose levels to the non-invasive model (plus-fasting plasma glucose model). The area under the curve of the non-invasive model was 0.700 and it increased significantly to 0.772 (P < 0.001) in the plus-fasting plasma glucose model. The ability of the non-invasive model to predict Type 2 diabetes was comparable with that of impaired glucose tolerance, and the plus-fasting plasma glucose model was superior to it. The cumulative incidence of Type 2 diabetes was significantly increased with elevating quintiles of the sum scores of both models in the validation cohort (P for trend < 0.001).

CONCLUSIONS

We developed two practical risk score models for easily identifying individuals at high risk of incident Type 2 diabetes without an oral glucose tolerance test in the Japanese population.

Cut-off values of fasting and post-load plasma glucose and HbA1c for predicting Type 2 diabetes in community-dwelling Japanese subjects: the Hisayama Study

AIMS

We examined the optimal cut-off values of fasting plasma glucose, 2-h post-load glucose and HbA(1c) for predicting Type 2 diabetes in community-dwelling Japanese subjects.

METHODS

A total of 1982 subjects without diabetes aged 40-79 years who underwent a 75-g oral glucose tolerance test were followed prospectively for 14 years by annual health examination.

RESULTS

During the follow-up, 295 subjects developed Type 2 diabetes. Compared with the first decile, the crude hazard ratio for incident Type 2 diabetes was significantly higher in the fifth fasting plasma glucose decile [5.4-5.4 mmol/l (97-98 mg/dl)] or higher, in the seventh 2-h post-load glucose decile [6.9-7.2 mmol/l (124-131 mg/dl)] or higher, and in the fifth HbA(1c) decile [34-36 mmol/mol (5.3-5.4%)] or higher. These associations remained substantially unchanged even after adjustment for confounding factors. The receiver operating characteristic curve analysis showed that the optimal cut-off values for predicting Type 2 diabetes were 5.6 mmol/l (101 mg/dl) for fasting plasma glucose, 6.9 mmol/l (124 mg/dl) for 2-h post-load glucose and 37 mmol/mol (5.5%) for HbA(1c). In a stratified analysis, the cut-off values were approximately 5.6 mmol/l (101 mg/dl) for fasting plasma glucose and 37 mmol/mol (5.5%) for HbA(1c), and these values were unchanged over BMI quartile levels, whereas the 2-h post-load glucose cut-off values declined with decreasing BMI levels.

CONCLUSIONS

Our findings suggest that the cut-off value for predicting Type 2 diabetes in the Japanese population is 5.6 mmol/l (101 mg/dl) for fasting plasma glucose and 37 mmol/mol (5.5%) for HbA(1c), while the 2-h post-load glucose cut-off value is lower than the diagnostic criterion for impaired glucose tolerance.

Impact of Sirolimus-Eluting Stent Fracture on 4-Year Clinical Outcomes

Background—

Although stent fracture (SF) after sirolimus-eluting stent (SES) implantation has been recognized as one of the predisposing factors of in-stent restenosis, it remains uncertain whether SF can increase the risk of major adverse cardiac events (MACE), especially beyond 1 year after SES implantation. The aim of this study was to assess the impact of SF relative to non-SF on 4-year clinical outcomes after treatment with SES of comparable unselected lesions.

Methods and Results—

A total of 874 lesions in 793 patients undergoing SES implantation and subsequent angiography 6 to 9 months after index procedure were analyzed. At 6- to 9-month angiographic follow-up, SF was identified in 70 of 874 lesions (8.0%). In-stent late loss was significantly higher in SF lesions versus non-SF lesions (0.42±0.59 mm versus 0.13±0.49 mm, P <0.001), resulting in a significantly higher in-stent restenosis rate (21.4% versus 4.1%, P <0.001). At 4 years, SF versus non-SF was associated with a significantly higher MACE rate (23.2% versus 12.6%, P =0.014), mainly driven by significantly higher target-lesion revascularization (18.8% versus 10.2%, P =0.029) rate. Adverse effects of SF on clinical outcomes occurred mostly within the first year (17.4% versus 6.6%, P =0.001), with similar MACE rate between 1 and 4 years (5.8% versus 5.9%, P =0.611). No significant differences between SF versus non-SF patients were observed in the cumulative frequency of very late stent thrombosis (2.9% versus 1.4%, P =0.281), death (0% versus 2.1%, P =0.252), or myocardial infarction (5.8% versus 2.9%, P =0.165).

Conclusions—

SF of SES was associated with higher MACE rate up to 1 year, mainly driven by higher target-lesion revascularization, whereas no significant association was evident between years 1 and 4.

Electrical Contacts to Polycrystalline B Doped Diamond Films

B doped diamond films were synthesized by microwave plasma CVD and electrical contacts were fabricated by R F sputtering. Rc was obtained for Pt, Ni, TaSi2, and Al asdeposited contacts at room temperature. Pt gave the minimum Rc and Al gave the maximum Rc of the metals investigated on films containing a carrier concentration of 5 × 1018/cm3. The minimum Rc, 8.6 × 10−4 Ω cm 2, was obtained on heavily B doped diamond films with a carrier concentration of 2.7 × 1020/cm3. After nnealing at 400 °C, the Rc of Pt contacts on B doped diamond films with a resistivity of 2×104 Ω1 cm decreased by approximately one order of magnitude.

Subtle myocardial damage associated with diagnostic coronary angiography alone

AIMS

To evaluate the frequency, predictors and prognostic significance of elevation in cardiac troponin I (cTnI) after coronary angiography (CAG).

METHODS AND RESULTS

A series of 296 consecutive patients with normal pre-procedural cTnI levels and undergoing elective CAG at our centre were prospectively analysed. Positive cTnI elevation was defined as >0.06 ng/ml. Positive cTnI elevation was observed in 44 patients (14.8%), but CK-MB was elevated in only four patients (1.3%) after the procedure. The risk of cTnI elevation was independently associated with left ventricular hypertrophy (odds ratio [OR] 5.52; 95% confidence interval [CI], 2.54 to 12.02; P<0.001), inexperienced operator (OR 10.83; 95% CI, 2.47 to 47.43; P=0.002) and the amount of contrast agent (OR 1.12; 95% CI, 1.03 to 1.23; P=0.009 for each 10 ml increase), whereas it was not associated with the severity of coronary artery disease. At one year, however, postprocedural elevation of cTnI was not associated with an increased risk of death (2.3% vs. 0.8%, P=0.384) or myocardial infarction (2.3% vs. 2.0%, P=0.623).

CONCLUSIONS

A minor elevation of cTnI is observed commonly after CAG, which might be associated with left ventricular hypertrophy, operator's experience and the amount of contrast used; however, it does not influence 1-year events rates.

A case of recurrent type 1 diabetes mellitus with insulitis of transplanted pancreas in simultaneous pancreas-kidney transplantation from cardiac death donor

AIMS/HYPOTHESIS

A 41-year-old woman undergoing simultaneous pancreas-kidney transplantation from an HLA-mismatched cardiac death donor abruptly developed overt hyperglycaemia under standard immunosuppressive therapy at 48 months after transplantation. Unexpectedly, we found insulitis in the transplanted pancreas and characterised the insulitis.

METHODS

Pancreas graft biopsies were performed 3 years before and after the development of hyperglycaemia and the specimens were examined histologically.

RESULTS

Insulitis was absent in the first biopsy, although oxidative DNA changes revealed by 8-hydroxy-2'-deoxyguanosine (8-OHdG) staining were diffusely present both in islet cells and exocrine cells. No Ki67-positive proliferating cells were seen in the islets. Anti-glutamic acid decarboxylase antibody was undetectable 6 months earlier but increased to 6.3 U/l at the development of hyperglycaemia. The level of anti-insulinoma-associated protein 2 antibody was 18.5 U/l. Insulin secretion was severely suppressed and insulin therapy was resumed. In the second biopsy, although acute allograft rejection was minimal, insulin-positive beta cells were markedly reduced, and glucagon-positive alpha cells predominated. CD3-positive T lymphocytes, CD8-positive cytotoxic T lymphocytes and CD68-positive macrophages infiltrated around and into islets. The infiltrating cells expressed Fas ligand as well as granzyme B. More than 80% of islets were affected by insulitis. 8-OHdG-positive cells were also present in islets and exocrine tissue. The percentage of Ki67-positive cells in total islet cells was 1.5%. There were no TUNEL-positive apoptotic cells in the islet cells.

CONCLUSIONS/INTERPRETATION

The histological features of insulitis in transplanted pancreas were consistent with common type 1 diabetes mellitus, but the clinical course of the recurrence appeared to be more rapid.

Beneficial effects of growth hormone-releasing peptide on myocardial oxidative stress and left ventricular dysfunction in dilated cardiomyopathic hamsters

BACKGROUND

Growth hormone-releasing peptide (GHRP) may act directly on the myocardium and improve left ventricular (LV) function, suggesting a potential new approach to the treatment of cardiomyopathic hearts. The present study tested the hypothesis that the beneficial cardiac effects of GHRP might include attenuation of myocardial oxidative stress.

METHODS AND RESULTS

Dilated cardiomyopathic TO-2 hamsters were injected with GHRP-2 (1 mg/kg) or saline from 6 to 12 weeks of age. F1B hamsters served as controls. Untreated TO-2 hamsters progressively developed LV dilation, wall thinning, and systolic dysfunction between 6 and 12 weeks of age. Marked myocardial fibrosis was apparent in untreated hamsters at 12 weeks of age in comparison with F1B controls. The ratio of reduced to oxidized glutathione (GSH/GSSG) was decreased and the concentration of 4-hydroxynonenal (4-HNE) was increased in the hearts of untreated TO-2 hamsters. Treatment with GHRP-2 attenuated the progression of LV remodeling and dysfunction, as well as myocardial fibrosis, in TO-2 hamsters. GHRP-2 also inhibited both the decrease in the GSH/GSSG ratio and the increase in the concentration of 4-HNE in the hearts of TO-2 hamsters.

CONCLUSIONS

GHRP-2 can suppress the increase in the level of myocardial oxidative stress, leading to attenuation of progressive LV remodeling and dysfunction in dilated cardiomyopathic hamsters. (Circ J 2010; 74: 163 - 170).

Relationship between severity of renal impairment and 2-year outcomes after sirolimus-eluting stent implantation

BACKGROUND

The presence of chronic kidney disease (CKD) is associated with an increased risk of restenosis and major adverse cardiac events (MACEs) after coronary interventions, especially in patients on hemodialysis (HD). The aim of this study was to assess the impact of varying degrees of renal impairment on angiographic and 2-year clinical outcomes after treatment with sirolimus-eluting stents (SESs).

METHODS

A total of 675 lesions of 593 patients treated with SES were analyzed. Patients were classified into 3 groups: 34 patients on HD; 337 patients with estimated glomerular filtration rate > or =60 mL min(-1) 1.73 m(-2) (non-CKD group); and 222 patients who had lower estimated glomerular filtration rate <60 mL min(-1) 1.73 m(-2) without HD dependency (CKD group).

RESULTS

At angiographic follow-up (201 +/- 73 days), in-segment late loss was markedly higher in the HD group versus the non-CKD and CKD groups (0.68 +/- 1.06 vs 0.11 +/- 0.45 and 0.15 +/- 0.50 mm, respectively, P < .001), resulting in a significantly higher in-segment restenosis rate (40.0% vs 10.4% and 11.5%, respectively, P < .001). At 2 years, HD vs non-CKD and CKD was associated with a significantly higher MACE rate (35.3% vs 10.4% and 12.6%, respectively, P < .001), mainly driven by significantly higher mortality (11.8% vs 0.6% and 2.3%, respectively, P < .001) and target-lesion revascularization (23.5% vs 9.2% and 8.1%, respectively, P = .016) rates. Multivariable analysis revealed that HD was the independent predictor of 2-year MACE (hazard ratio 4.70, 95% CI 2.40-9.20, P < .001).

CONCLUSIONS

Although angiographic and clinical outcomes after SES implantation were similarly favorable in non-HD-dependent CKD patients, regardless of renal function, in patients with end-stage CKD requiring HD, frequencies of restenosis and 2-year MACE were markedly higher than in non-HD-dependent patients.

Serum high-molecular weight adiponectin is related to early postprandial glycemic increases and gastric emptying in patients with type 2 diabetes mellitus

BACKGROUND

Postprandial hyperglycemia and hyperlipidemia are frequently associated with type 2 diabetes mellitus. The aim of the present study is to investigate the clinical determinants of postprandial glycemia and lipemia, especially serum high-molecular weight adiponectin.

METHODS

Twenty-seven diabetic patients treated with diet alone and 13 healthy volunteers took liquid test meal containing 53 g carbohydrate and 47 g lipid, dosed with nonradioactive isotope (13)C-acetate. Venous blood and breath samples were obtained for 180 min after the meal. Gastric emptying was evaluated by peak excretion time of (13)CO(2) in the breath samples. Delayed gastric emptying was defined as peak excretion time > 2.5 h (mean + 2 SD in the healthy volunteers).

RESULTS

Diabetic patients showed delayed insulin secretion, postprandial hyperglycemia and hyperlipidemia compared with control. Postprandial glycemic increases significantly correlated with enhanced gastric emptying. Serum high-molecular weight adiponectin correlated with postprandial glycemic increases at 30 and 60 min after meal (r = 0.42, p < 0.05; r = 0.37, p < 0.05, respectively). Serum high-molecular weight adiponectin also correlated with gastric emptying (versus peak excretion time r = - 0.58, p < 0.05). In addition, diabetic patients with delayed gastric emptying showed the suppressed postprandial glycemia with lower serum high-molecular weight adiponectin than those with normal gastric emptying. On the other hand, postprandial increases in serum triglyceride were not related to serum high-molecular weight adiponectin or gastric emptying, but significantly related to liver function test (serum transaminases) and body mass index.

CONCLUSIONS

Early postprandial glycemic increases were related to elevated serum high-molecular weight adiponectin, which might be associated with enhanced gastric emptying.

Is it possible to predict which patients need distal protection during primary angioplasty?

BACKGROUND

Although the benefit of distal protection (DP) during primary percutaneous coronary intervention (PCI) remains questionable, there appears to be efficacy in some clinical situations. We sought to identify in patients with ST-segment elevation acute myocardial infarction (STEMI) which clinical and angiographic characteristics might indicate the patient who will benefit from the use of a DP device.

METHODS

A series of 103 consecutive patients with STEMI undergoing primary PCI using DP were compared with 98 consecutive patients treated by primary PCI alone.

RESULTS

The overall rates of thromboembolic complications and achievement of optimal reperfusion (myocardial blush grade >/=2 and ST-segment resolution >/=70%), and infarct size, were similar between the 2 groups. However, DP use was associated with higher rates of optimal reperfusion in patients with right coronary artery (RCA) lesions (OR 2.45; 95% CI, 1.07 to 5.59; P=0.034), thrombus score >/=4 (OR 2.64; 95% CI, 1.07 to 6.50; P=0.034) or infarct-related artery (IRA) of >/=3.5 mm in diameter (OR 4.09; 95% CI, 1.02 to 16.40; P=0.047). In this population (RCA location, thrombus score >/=4, or IRA >/=3.5 mm), DP use reduced the risk of thromboembolic complications (64%, P=0.012, 45%, P=0.035 and 54%, P=0.050, respectively), resulting in a smaller infarct size (8.0+/-5.1 vs. 11.7+/-7.5, P=0.028, 13.1+/-8.8 vs. 17.4+/-10.0, P=0.026 and 15.5+/-10.8 vs. 22.1+/-10.1, P=0.042, respectively).

CONCLUSIONS

The use of a DP during primary PCI may lead to a reduction of thromboembolic complications, subsequent higher rates of optimal reperfusion and reduced infarct size in patients with RCA culprit lesions, a large thrombus, or large IRA.

Xanthine oxidase inhibition improves left ventricular dysfunction in dilated cardiomyopathic hamsters

BACKGROUND

Oxidative stress is implicated in cardiac remodeling and failure. We tested whether xanthine oxidase (XO) inhibition could decrease myocardial oxidative stress and attenuate left ventricular (LV) remodeling and dysfunction in the TO-2 hamster model of dilated cardiomyopathy.

METHODS AND RESULTS

TO-2 hamsters were randomized to treatment with the XO inhibitor, allopurinol, or vehicle from 6 to 12 weeks of age. F1B hamsters served as controls. TO-2 hamsters treated with vehicle progressively developed severe LV systolic dysfunction and dilation between 6 and 12 weeks. Marked cardiac fibrosis was apparent in these hamsters at 12 weeks in comparison with F1B controls. The ratio of reduced to oxidized glutathione (GSH/GSSG) was decreased and malondialdehyde levels were increased in the hearts of vehicle-treated TO-2 hamsters. Treatment with allopurinol from 6 to 12 weeks attenuated LV dysfunction and dilation as well as myocardial fibrosis and the upregulation of a fetal-type cardiac gene. Allopurinol also inhibited both the decrease in GSH/GSSG ratio and the increase in malondialdehyde levels in the heart.

CONCLUSIONS

These results indicate that chronic XO inhibition with allopurinol attenuates LV remodeling and dysfunction as well as myocardial oxidative stress in this model of heart failure. Allopurinol may prove beneficial for the treatment of heart failure.

Frequency, predictors and outcome of stent fracture after sirolimus-eluting stent implantation

BACKGROUND

Recently, stent fracture (SF) of sirolimus-eluting stents (SES) has been shown to be associated with an increased risk of in-stent restenosis. We sought to evaluate the incidence, predictors and clinical outcome of SF after SES implantation in comparable unselected lesions.

METHODS

A total of 430 lesions of 382 patients treated with SES were analyzed. SF was defined as single or multiple stent strut fracture as well as complete separation of stent segments.

RESULTS

At follow-up, SF was identified in 33 of 430 lesions (7.7%). In lesions with SF, the in-stent restenosis was observed more frequently than non-SF lesions (15.2% vs. 4.0%, P=0.004). At 450 days, however, the cumulative rate of major cardiac events was not significantly different between lesions with and without SF (9.1% vs. 7.1%, P=0.722). The risk of SF was independently associated with total stent length (OR 2.22; 95% CI, 1.25 to 3.95; P=0.007), the change in the angulation of the lesion after stenting (OR 1.55; 95% CI, 1.07 to 2.25; P=0.020), and the right coronary artery lesions (OR 3.26; 95% CI, 1.18 to 8.96; P=0.022).

CONCLUSIONS

The occurrence of SF after SES implantation, was found to be relatively common in the particular population, however, did not lead to an increased risk of adverse cardiac events at 450 days, despite a higher incidence of in-stent restenosis.

Altered Postural Regulation of Foot Skin Oxygenation and Blood Flow in Patients with Type 2 Diabetes Mellitus

AIMS

Although skin oxygenation is an important factor in the development and healing of foot ulcers, its regulation was not fully understood. We studied changes in foot skin oxygenation and blood flow during postural changes in patients with type 2 diabetes mellitus.

METHODS

Skin oxygenation was measured using transcutaneous oxygen pressure (TcPO(2)) and skin blood flow by laser Doppler flowmetry in 40 patients with type 2 diabetes mellitus without evidence of peripheral arterial disease and 13 healthy control subjects.

RESULTS

TcPO(2) in the supine position was significantly lower in patients with type 2 diabetes mellitus compared with control, although skin blood flow was not different. In the sitting position, TcPO(2) significantly increased in control and diabetic patients. The postural change-related increase in TcPO(2) was significantly enhanced in diabetic patients. On the other hand, skin blood blow significantly decreased in the sitting position from the supine position in control subjects but remained stable in diabetic patients. Orthostatic drop in systolic blood pressure correlated negatively with TcPO(2) in the supine position while correlated positively with %change in TcPO(2) and blood flow by postural changes.

CONCLUSIONS

The present study demonstrated the dissociated regulation of skin oxygenation and blood flow in response to leg dependency. Impaired postural vasoconstriction was associated with altered regulation of skin oxygenation probably due to sympathetic vascular dysfunction in diabetic patients.

Diversity of the Elevation of Serum Cardiac Troponin I Levels in Patients During Their First Visit to the Emergency Room

BACKGROUND

Although measurement of serum creatine kinase levels, as well as myoglobin levels, has been used for screening patients with acute coronary syndrome (ACS), the specificity of both is low. Measurement of cardiac troponin levels is now extensively used for the diagnosis of ACS because of their superior cardiac specificity. However, troponin levels are reportedly elevated not only in patients with ACS but also in those with other diseases.

METHODS AND RESULTS

The clinical characteristics of 1,023 patients (mean age: 63.5+/-16.3 years; males: 665, females: 358) whose serum cardiac troponin I (cTnI) levels had been measured at the initial visit to the emergency room of Toyota Memorial Hospital between April 2004 and March 2005 were retrospectively analyzed. A positive elevation of cTnI was defined as cTnI > or =0.03 ng/ml. There were 432 patients (42.2%) with positive cTnI levels. The cTnI levels (8.48+/-2.64 ng/ml) in patients with acute myocardial infarction (AMI) were greater than those (0.25+/-0.07 ng/ml) in patients with unstable angina pectoris (AP), as well as those (0.04+/-0.01 ng/ml) in patients with stable AP. In terms of the diagnosis of AMI, the sensitivity was high enough (94.6%), but its specificity was relatively low (61.9%). Furthermore, the differentiation between AMI and unstable AP by the cTnI value alone was impossible. The cTnI levels were elevated in patients with a variety of diseases other than ACS, including heart failure, cardiomyopathies, myocarditis, renal failure, tachyarrhythmias, and pulmonary embolism.

CONCLUSIONS

Elevation of the cTnI level is frequently observed in patients in the emergency room with common diseases other than ACS.