Steno type 1 risk engine and preclinical atherosclerosis in Mediterranean individuals with type 1 diabetes

BACKGROUND AND AIMS

Tools to detect type 1 diabetes (T1D) individuals at overt cardiovascular disease (CVD) risk are scarce. We aimed to assess the usefulness of the score 'Steno Type 1 Risk Engine' (Steno-Risk) to identify T1D patients with advanced carotid atherosclerosis.

MATERIAL AND METHODS

T1D patients without CVD with at least one of the following were included: ≥40 years, diabetic nephropathy, or diabetes duration ≥10 years with ≥1 CVD risk factor. Intima-media thickness (IMT) and plaque presence (IMT ≥1.5 mm) were assessed by standardized B-mode ultrasonography. Steno-Risk was used to estimate 10-year risk (<10% low; 10%-20% moderate; ≥20% high risk). Associations between Steno-Risk and preclinical atherosclerosis were assessed after adjusting for other CVD risk factors.

RESULTS

We evaluated 302 patients (55% men, age 47.8 ± 9.8 years, T1D duration 26.3 ± 9.3 years). The prevalence of carotid plaque and ≥2 plaques were 36.4% and 19.2%, respectively; without sex differences. Age (57.4 ± 7.4 vs 37.1 ± 6.2 years), T1D duration (31.3 ± 10.4 vs 21.5 ± 7.1 years), hypertension (52.3% vs 6.3%), nephropathy (25.6% vs 5.1%) and retinopathy (53.5% vs 32.9%) were higher in high-risk (n = 86) vs low-risk participants (n = 79; P < .001 for all). Preclinical atherosclerosis (IMT and plaque) increased in parallel with Steno-Risk (P < .001). In logistic regression analysis, both age ≥40 years and Steno-Risk ≥20% were associated with the presence of plaque (OR 4.22 [1.57-11.36] and 3.79 [1.61-6.80]; respectively), but only high Steno-Risk remained independently associated with ≥2 plaques (OR 3.31 [1.61-6.80]).

CONCLUSION

Steno-Risk is independently associated with preclinical atherosclerosis. Further studies are needed to ascertain its usefulness in this high-risk population.

Cyclosporine Does not Inhibit the Process of Revascularization of Pancreatic Islet Transplantation

The immunosuppressive drug cyclosporin-A (CsA) has been widely used to prevent pancreatic islet allograft rejection. Because it has been suggested that CsA may inhibit the process of revascularization of transplanted islets, the purpose of the study was to analyze by a double indirect immunofluorescence technique the revascularization process of isolated islets grafted in the liver and in the renal subcapsular space of rats treated with immunosuppressive doses of CsA. Lewis rats were grafted with either Lewis (isografts) or Wistar (allografts) pancreatic islets obtained by collagenase digestion. Rats were killed at different days after implantation and the liver and kidney bearing the grafted islets were snap frozen and immunohistochemically stained with a double immunofluorescence technique using a rabbit antifactor-VIII antiserum (which labels endothelial cells) and a guinea pig antiinsulin antibody. Islets implanted into nonimmunosuppressed hosts completed revascularization by days 3-7 after transplantation, as shown by the detection of endothelial cells within and surrounding the islets. The identical staining pattern of revascularization was observed in nonrejecting allografts as well as in isografts treated with CsA. We conclude that CsA did not inhibit the process of revascularization of rat islets after free transplantation. This finding is relevant for human islet transplantation, where CsA is currently employed to prevent kidney and islet allograft rejection. Copyright © 1997 Elsevier Science Inc.

Effect of Fusidic Acid on Pancreatic Islet Allograft Rejection

We examined in fully mismatched rats, the survival of pancreatic islet allografts in recipients treated with either fusidic acid (FA), an antistaphyllococcal antibiotic that has been shown to possess an immunosuppressive effect in vitro and in vivo, or cyclosporin-A (CsA). Islets were isolated by collagenase digestion, separated from acinar tissue by handpicking under a dissecting microscope and transplanted into the liver by portal vein injection of streptozotocin(STZ)-induced diabetic rats. The results indicated that while a temporary immunosuppression with CsA achieved an indefinite islet allograft survival, FA administered to recipients daily was not able to prevent islet allograft rejection across a major histocompatibility barrier. We conclude that despite the fact that fusidic acid has been claimed to act as an immunosuppressant drug in vitro with effects similar to those of CsA, unlike CsA, FA given either orally or by s.c. injection was not effective to prolong islet allograft survival in vivo. Copyright © 1997 Elsevier Science Inc.

Simultaneous Pancreas-Kidney Transplantation: Is the Failure of the Grafts Also Simultaneous?

INTRODUCTION

It is well known that after a simultaneous pancreas and kidney transplantation (SPKT) there is a higher incidence of pancreatic graft loss in the acute period, due to technical problems. However, there is little information about the survival of pancreatic and kidney grafts 1 year after transplantation.

AIMS

To analyze the causes of long-term graft loss of SPKT in our hospital and to determine if this loss occurs simultaneously or is isolated.

PATIENTS AND METHODS

We analyzed the data of 63 SPKTs performed between February 1983 and October 2005, including the cases with normal renal and pancreatic function after 1 year of transplantation, and with a loss of one or two organs during the follow-up period (8 +/- 4 years). We defined simultaneous SPKT failure as failure that occurs at the same time or when the period between pancreatic and renal graft failure is shorter than 9 months.

RESULTS

In 28 patients (44%), there was a simultaneous graft failure, whereas in 35 (56%) the loss of function occurred in only one organ or in both, but separately. Death was responsible for 75% (21/28) of simultaneous graft losses, representing 25% (9/35) of isolated graft failures. Cardiovascular disease was the leading cause of death. In 14 of 35 isolated graft failures, there was loss of renal and pancreatic function (11/14 kidney failed first) with a 2.9 +/- 2.3 years of interval. In 12 cases there was only loss of pancreatic function, whereas in nine cases the affected organ was the kidney. Graft chronic nephropathy and chronic rejection in the pancreas were the main causes of graft failure.

CONCLUSIONS

The main cause of simultaneous SPKT failure is patient death; however, among isolated or separated SPKT failures, the kidney failed first, more frequently.

Estrategias para un control eficaz de la hipertensión arterial en España. Documento de consenso

Blood pressure (BP) control is inadequate among treated hypertensive patients in Spain. Control rates are lower than 40% of all treated patients and the cause of this problem is multifactorial. Despite the fact that possible solutions to this problem have been repeatedly suggested by expert groups along the last 10 years, BP control rates are still low. This fact have a negative impact on cardiovascular morbidity and mortality of patients with hypertension. The aim of the present document has been to achieve a consensus on effective specific measures in order to improve hypertension control rates in Spain. These measures involve health care professionals (physicians, nurses, pharmaceutics), health care authorities and patients. The document summarizes the consensus conference of several scientific societies involved in cardiovascular medicine in five group of measures: a) improvement of the methodology of office BP measurement; b) improvement of compliance to treatment by patients; c) clarification of pressure targets to be achieved in hypertensive patients; d) optimization of life style modifications and pharmacological treatment of hypertension; and e) continuous medical education. The document emphasize life style changes as a crucial aspect to be implemented in all patients. These changes have a beneficial impact on pressure reduction, contribute to a better control of associated cardiovascular risk factors, and increase the effectiveness of antihypertensive drugs. Health care professionals should base their clinical practice on the recommendations of guidelines in order to modify their therapeutic attitudes in patients whose targets have not been achieved.

Telecare in a structured therapeutic education programme addressed to patients with type 1 diabetes and poor metabolic control

OBJECTIVE

To assess the effects of telecare on the results of intensive follow-up in T1D patients with poor metabolic control.

METHODS

After initial evaluation, 40 T1D were randomised to either a Telecare (TG) or Conventional Group (CG). Patients had an intensive 6-month follow-up and helped to make decisions concerning treatment self-management. The TG had 12 appointments: 9 telematic with the GlucoBeep system+3 ambulatory. The CG had 12 outpatient appointments. At 0, 6 (end of study) and 12 months, metabolic control, self-management and quality of life were evaluated. Cost analysis was made at study end.

RESULTS

Thirty patients completed the study (16 TG, 14 CG). Intention to treat analysis included 19 TG and 16 CG. Improvement in HbA(1c) was similar in both groups TG: 8.4+/-1.2%; 7.5+/-1.4%; 7.6+/-0.9%, p=0.008; CG: 8.9+/-1.3%; 7.7+/-0.9%; 7.6+/-0.7%, p=0.001; with a decrease in hypoglycaemic events and improvement in self-management and quality of life. Patient costs were lower in the TG versus CG in appointment length (0.25h versus 0.5h). However, 30% of the diabetes team and patient appointments were longer than expected due to technical difficulties: (0.25h versus 1h).

CONCLUSIONS

Intensive telematic follow-up achieves similar results to those of intensive face-to-face follow-up with lower patient costs. However, communication technology must be improved.

F2 isoprostane is already increased at the onset of type 1 diabetes mellitus: effect of glycemic control

Much evidence has suggested that oxidative stress (OS) may play a role in the pathogenesis of diabetic complications. However, the relationship between hyperglycemia and OS is inconsistent in diabetic clinical studies. The aim of this study was to evaluate the effect of normalization of blood glucose levels on urinary 8-epi-prostaglandin F(2alpha) (8-epi-PGF(2alpha)) excretion at the onset of type 1 diabetes. We studied 14 type 1 diabetic patients (50% males; mean age, 24.3 +/- 4.9 years) and 14 control subjects matched by age and body mass index. A 24-hour urine collection was performed to determine 8-epi-PGF(2alpha) as an integrated index of OS production at baseline, before starting insulin therapy, and 16 weeks later. Insulin treatment induced a significant reduction in glycosylated hemoglobin (HbA(1c)) (from 11.5% to 5.4% P =.0001), triglycerides (from 1.0 to 0.8 mmol/L, P =.002), and an increase in high-density lipoprotein (HDL)-cholesterol levels (from 1.1 to 1.5 nmol/L, P =.01) at week 16. This improvement in metabolic control was associated with a statistically significant reduction in 8-epi-PGF(2alpha) values (from 92.0 +/- 41.5 to 66.9 +/- 28.9 pg/mg urinary reatinine excretion, P =.015), although compared with the control group, 8-epi-PGF(2alpha) values remained higher in diabetic patients (66.9 +/- 28.9 v 39.1 +/- 13.8 pg/mg creatinine, P =.004). Enhanced OS is present in early clinical phases of type 1 diabetes, and the amelioration in metabolic control is associated with improvement in this pathogenic pathway.

Transforming growth factor beta at clinical onset of Type 1 diabetes mellitus. A pilot study

AIMS

The aims of the study were to determine whether transforming growth factor beta1 TGF-beta1 levels are raised at diagnosis of Type 1 diabetes mellitus and are related to blood glucose.

SUBJECTS AND METHODS

Fourteen patients (mean age 24.3 +/- 4.9 years) admitted to hospital for onset of Type 1 diabetes were studied. On the first day of hospitalization, before insulin therapy, and at 1, 4 and 16 weeks, fasting blood glucose, HbA(1c), lipid profile and TGF-beta1 levels and TGF-beta1 levels in 24-h urine were determined. The control group included 14 non-diabetic subjects with similar characteristics to those of the diabetic group.

RESULTS

Plasma and urinary TGF-beta1 levels were significantly lower in controls (4.7 (1.6-6.8) ng/ml P < 0.001; 5.7 (1.5-8.5) ng/mg urinary creatinine, P < 0.01) than in patients with Type 1 diabetes mellitus [10.5 (1.8-24.9) ng/ml; 10.1 (4.2-29.8) ng/mg urinary creatinine]. On study completion, HbA(1c) fell from 11.6 +/- 2.0 to 5.4 +/- 0.6% (P < 0.001). Improved metabolic control was not associated with changes in plasma (9.4 (2.6-19.5)/5.9 (1.6-21.5)/7.0 (2.3-30.2)/10.5 (1.8-24.9) ng/ml at baseline, 1, 4 and 16 weeks, respectively) or urinary (12.0 (4.7-29.5)/10.9 (1.5-20.5)/8.7 (4.3-16.9)/10.1 (4.2-29.8) ng/mg urinary creatinine) TGF-beta1 levels. A statistically significant correlation was observed between plasma TGF-beta1 and insulin dosage (U/kg/day) (r = 0.52, P = 0.037).

CONCLUSIONS

The increased TGF-beta1 production observed herein was not modulated by glycaemic reduction and could be a response to immuno-inflammatory activation present at the onset of Type 1 diabetes.

Cigarette smoke concentrate increases 8-epi-PGF2alpha and TGFbeta1 secretion in rat mesangial cells

Epidemiological studies have shown that cigarette smoke, an oxidant agent, is a risk factor for the development of diabetic nephropathy (DN), in which pathogenesis transforming growth factor beta(1) (TGFbeta(1)) plays a key role. In our experimental model we exposed mesangial cell cultures to cigarette smoke concentrate (CSC) to study the effect of smoking on the pathogenesis of DN. Thus, we analyzed the effect of CSC on TGFbeta(1) and lipid peroxidation (8-epi-PGF(2alpha)) in rat mesangial cells. Furthermore, since the protein kinase C (PKC) pathway appears to be a key factor for the enhanced production of TGFbeta(1), we also analyzed the effect of the selective PKCbeta inhibitor LY379196 on TGFbeta(1) response to CSC. CSC induced an increase of both TGFbeta(1) and 8-epi-PGF(2) compared to basal conditions (5 mM glucose). The CSC-induced increase in TGFbeta(1) secretion was significantly suppressed by LY379196. These data suggest that smoking could increase TGFbeta(1) production, probably due to oxidative stress and PKCbeta activation. This finding supports the concept that smoking is a risk factor for DN development.

The effects of smoking and its cessation on 8-epi-PGF2alpha and transforming growth factor-beta 1 in Type 1 diabetes mellitus

BACKGROUND

Oxidative stress and transforming growth factor-beta 1 (TGF-beta1) are associated with diabetic complications, and smoking is a risk factor.

AIMS

This study aimed (i) to compare urinary 8-epi-PGF2alpha and plasma and urinary TGF-beta1 levels obtained in heavy smokers with Type 1 diabetes with those observed in age-matched non-smoker patients with Type 1 diabetes and controls, and (ii) to investigate the effects of smoking cessation (SC) on the above-mentioned parameters in patients with Type 1 diabetes.

METHODS AND RESULTS

Compared with control subjects (n = 12), non-smoker diabetic patients (n = 12) presented higher values of urinary 8-epi-PGF2alpha (74.2 +/- 29.6 vs. 29.6 +/- 11.1 pg/mg urinary creatinine, P = 0.01), plasma TGF-beta1 (7.7 +/- 4.7 vs. 3.6 +/- 1.7 ng/ml, P = 0.001) and urinary TGF-beta1 (15.3 +/- 6.3 vs. 8.1 +/- 4.4 ng/mg urinary creatinine, P = 0.02). Compared with non-smoker diabetic patients, smoker diabetic patients (n = 16) showed higher levels of urinary 8-epi-PGF2alpha (107.8 +/- 40.2 vs. 74.2 +/- 29.6 pg/mg urinary creatinine, P = 0.0001), plasma TGF-beta1 (12.6 +/- 4.9 vs. 7.7 +/- 4.7 ng/ml, P = 0.001) and urinary TGF-beta1 (27.5 +/- 16.0 vs. 15.3 +/- 6.3 ng/mg urinary creatinine, P = 0.01). Smoker patients were included in a smoking cessation programme. In the 10 patients that gave up smoking there was a reduction of urinary 8-epi-PGF2alpha (basal: 110.47 +/- 47.0 vs. week 12: 73.2 +/- 25.6; P < 0.001), plasma TGF-beta1 (basal: 11.2 +/- 5.9 vs. week 12: 4.89 +/- 2.25; P < 0.01) and urinary TGF-beta1 (basal: 18.12 +/- 9.27 vs. week 12: 10.32 +/- 2.0; P < 0.01) levels.

CONCLUSIONS

In patients with Type 1 diabetes, smoking increased oxidative stress, evaluated by lipid peroxidation, and TGF-beta1 production. Smoking cessation decreased these parameters, providing additional support to encourage diabetic patients to give up smoking.

Macrovascular events after kidney-pancreas transplantation in type 1 diabetic patients

BACKGROUND

There are few studies concerning the effect of kidney-pancreas transplantation (KPTx) on the progression of macrovascular disease in type 1 diabetic patients. The aim of our study was to retrospectively evaluate the incidence of macrovascular events after functioning KPTx.

MATERIALS AND METHODS

We studied 146 patients (96 men and 50 women) who had undergone KPTx from February 1983 to September 2001, with more than 1 year of evolution of both grafts functioning normally. The mean follow-up of the patients after KPTx was 5+/-3 years.

RESULTS

Before KPTx, 29 patients displayed 42 macrovascular events. During the follow-up after transplantation, intermittent claudication remained in 25 patients (86.2%) with 11 new macrovascular events (1 stroke, 1 angina pectoris, 1 myocardial infarction, and 8 minor amputations) in 10 patients (34%). Among the 117 patients without antecedent macrovascular events prior to KPTx, 38 (32.5%) experienced a total of 63 macrovascular events (26 intermittent claudication, 4 stroke, 8 angina pectoris, 7 myocardial infarction, 11 minor amputations, and 7 major amputations). Before transplantation, 88.4% of the patients presented with hypertension, 42.5% a history of smoking, and 14.4% previous treatment for dyslipidmia. After transplantation, we observed an important reduction in the percentage of patients with hypertension (48.6%) and smoking (25.5%), without a change in the prevalence of dyslipemia (19.9%). Hypertension after transplantation was clearly associated with the appearance or persistence of macrovascular events.

CONCLUSION

In our experience, 43% of the transplant recipients present with macrovascular events. It is important to note the elevated prevalence of cardiovascular risk factors in the patients who underwent KPTx.

Incidence of diabetic nephropathy in Type 1 diabetic patients in Spain: 'Estudio Diamante'

AIMS

To determine the prevalence and the incidence of diabetic nephropathy in Type 1 diabetes mellitus in Spain and to investigate the risk factors for the development of microalbuminuria.

METHODS

One thousand five hundred and two patients with Type 1 diabetes mellitus were prospectively followed in 15 hospital diabetes outpatient clinics in Spain. Blood pressure, body weight, HbA(1c), total cholesterol, HDL-cholesterol, triglycerides, plasma creatinine and urinary albumin excretion (UAE) were determined every 3-5 months.

RESULTS

A total of 1225 patients (624 males and 601 females), age 30.7+/-9.3 years with diabetes duration of 14.1+/-9.1 years completed 4.3 (4.0-5.1) years of follow-up. At baseline 14.2 (95% CI 12.3-16.3)% of patients had microalbuminuria, 5.1 (3.9-6.4)% macroalbuminuria and 3.4 (2.5-4.6)% kidney failure. During follow-up the annual incidence of microalbuminuria was 2.7 (2.2-3.2)%. In a multiple logistic regression analysis the predictors of progression to microalbuminuria were initial UAE, HbA(1c), diabetes duration, smoking, and HDL-cholesterol <0.9 mmol/l.

CONCLUSIONS

The prevalence and incidence of diabetic nephropathy in Spain are comparable to data obtained in similar studies carried out in other countries. The development of microalbuminuria is associated not only with glycaemic control and hypertension, but also to the control of other risk factors such as dyslipaemia and smoking.

Effect of losartan on TGF‐β1 and urinary albumin excretion in patients with type 2 diabetes mellitus and microalbuminuria

BACKGROUND

The aim of the present study was to determine the effect of losartan on transforming growth factor-beta1 (TGF-beta1) plasma levels and urinary albumin excretion (UAE) in patients with type 2 diabetes mellitus, mild hypertension and microalbuminuria.

METHODS

Fourteen patients (eight males, aged 55+/-6 years) with type 2 diabetes mellitus, mild arterial hypertension and microalbuminuria, participating in an open, uncontrolled, pilot study were included. Patients were treated for 8 weeks with losartan. TGF-beta1 plasma levels, UAE and 24-h blood pressure monitoring were determined at baseline and at 4 and 8 weeks.

RESULTS

At 4 and 8 weeks of treatment, a reduction was observed in TGF-beta1 plasma levels (5.5+/-4.5 vs 2.0+/-0.6 and 2.6+/-1.0 ng/ml, P<0.005), UAE (96+/-65 vs 59+/-59 and 64+/-47 microg/min, P<0.01), 24-h systolic blood pressure (136+/-9 vs 129+/-9 and 130+/-10 mmHg, P<0.01) and 24-h diastolic blood pressure (77+/-9 vs 74+/-8 and 74+/-7 mmHg, P<0.03). Stratifying the patients by baseline TGF-beta1, seven had TGF-beta1 plasma values higher than normal controls. At 4 and 8 weeks, they showed a marked reduction in TGF-beta1 values (9.0+/-3.9 to 2.1+/-0.7 and 2.5+/-0.7 ng/ml, P<0.01) and UAE (106+/-83 to 49+/-42 and 38+/-26 microg/min, P<0.05), with good correlation between the percentage reduction of both parameters (r=0.83, P<0.01). The remaining seven patients, with normal baseline TGF-beta1 plasma levels, showed no change in TGF-beta1 plasma levels and UAE after treatment.

CONCLUSION

Treatment with losartan decreases TGF-beta1 plasma values and UAE in type 2 diabetes mellitus patients with high baseline TGF-beta1 levels, suggesting that TGF-beta1 may be a marker to detect patients who may particularly benefit from renin-angiotensin system blockade.

White coat hypertension in type 1 diabetic patients without nephropathy

The aim of our study was to determine the prevalence of white coat hypertension (WCH) in type 1 diabetic patients. Therefore, ambulatory blood pressure monitoring (ABPM) and 24-h urinary albumin excretion (UAE) were determined in 47 patients with type 1 diabetes mellitus (27 with new diagnosis of hypertension by office blood pressure (BP) measurement and 20 with normotension). WCH was diagnosed in 20 patients (74%). Patients with WCH presented higher values of systolic and diastolic BP and UAE than normotensive patients. The results indicate that in type 1 diabetes mellitus WCH is very frequent. Thus, WCH may represent a potential risk for the development of diabetic complications, mainly diabetic nephropathy.

Usefulness of ambulatory blood pressure monitoring in pregnant women with type 1 diabetes

OBJECTIVE

Pregnancy in type 1 diabetes is associated with an increased risk of developing pregnancy-induced hypertension (PIH). Ambulatory blood pressure monitoring (ABPM) has been used to screen for preeclampsia in nondiabetic pregnancy. To date, there are no data regarding ABPM during pregnancy in normotensive type 1 diabetic women. This study sought to establish blood pressure (BP) profiles for pregnant type 1 diabetic women using ABPM and determine whether the BP pattern can define a population at risk for developing PIH.

RESEARCH DESIGN AND METHODS

ABPM was carried out for one 24-h period during each trimester--in the first trimester between weeks 7 and 12, in the second trimester between weeks 20 and 24, and in the third trimester between weeks 30 and 34--in 22 normotensive pregnant type 1 diabetic and 10 pregnant nondiabetic women.

RESULTS

The incidence of PIH was fourfold greater in type 1 diabetic women than in control subjects. Diabetic women showed higher daily diastolic BP in the third trimester compared with nondiabetic pregnant women. Diabetic women who developed PIH in the third trimester showed significantly higher BP profiles throughout gestation than those who remained normotensive. Receiver operator characteristics curves for nighttime systolic BP showed the best predictive capacity for PIH, with a cutoff > 105 mmHg (85% sensitivity and 92% specificity).

CONCLUSIONS

Our study confirms the early increase of BP in patients who will develop PIH and suggests that nighttime systolic BP >105 mmHg in the second trimester is a useful predictor of PIH. ABPM may be useful in screening for PIH in pregnant diabetic women.

[Renal failure secondary to diabetic nephropathy. A review of the characteristics of the diabetic patients who started dialysis in Catalonia in 1994]

The appearance of diabetic nephropathy and its progression towards renal failure can be prevented if an early treatment is instituted. However, diabetes is currently one of the main causes of entry into a dialysis program. Therefore, the diagnostic characteristics of renal disease in 105 patients who started dialysis in Catalonia in 1994 were reviewed; the presence of other changes associated with diabetes were assessed. The results showed that 81.7% of patients had proteinuria higher than 0.5 g/24 h, and 40.5% had plasma creatinine higher than 5 mg/dl at the first nephrological control. As a result, the period between diagnosis of nephropathy and the inclusion in the dialysis program was very short (3.7 years) and considerably shorter than that reflected in literature for other countries, whereas the incidence of other micro and macrovascular complications was similar. Remarkably, a high number of smokers and treatment with oral antidiabetic drugs (33%) at the end stage of renal failure was observed. These results suggest that follow-up of diabetics should be more exhaustive and serial tests be performed to detect nephropathy early. An appropriate control during renal failure stage can also postpone the disease progression and avoid the appearance of complications which at present have a high morbid-mortality and high cost.

Successful pancreas and kidney transplantation: a view of metabolic control

BACKGROUND

Pancreas and kidney transplantation (PKTx) has become the treatment of choice in uremic patients with insulin-dependent diabetes mellitus (IDDM). In these patients, the pancreatic graft provides an endogenous source of insulin. However, the determination of its long-term effect on metabolic control is crucial in order to establish the real efficacy of this treatment in diabetic patients. In this article, we describe the experience of the University of Barcelona in short- and long-term metabolic control in PKTx recipients.

SUBJECTS AND METHODS

We performed seriated determinations of glycosilated hemoglobin (HbA1c) and oral glucose tolerance tests (OGTT) in 55 patients who underwent PKTx at our center from 1983 to 1996 with both grafts functioning for more than 1 yr (mean follow-up 4.2 +/- 2.3 yr). Basal glucose and insulin levels, areas under the curve (AUC) of glycemia and insulinemia after OGTT were analyzed throughout follow-up, as well as fasting insulin resistance index (FIRI).

RESULTS

HbA1c levels throughout follow-up were within the normal range. The OGTT was normal in 80% of the patients 5 yr after transplantation. Hyperinsulinemia was present throughout follow-up. Over time, no differences were detected in the AUC of glycemia and insulinemia between controls and patients with PKTx. During the evolution, no differences were found in FIRI, in spite of increasing body weight.

CONCLUSION

When successful, PKTx provides long-term normalization of glycemic control, assessed by HbA1c and OGTT, despite the existence of sustained hyperinsulinemia. Our results strongly suggest that PKTx is the most effective treatment for uremic patients with IDDM from a metabolic point of view.

Insulin therapy in type 2 diabetic patients: effects on arterial blood pressure and endothelin-1 plasma levels

OBJECTIVE

To evaluate the possible effect of short- and long-term insulin treatment on arterial blood pressure (BP) and endothelin-1 (ET-1) plasma levels in type 2 diabetic patients.

RESEARCH DESIGN AND METHODS

Seven type 2 diabetic patients with secondary failure to oral hypoglycemic drugs (SFOH) were studied. Twenty-four-hour arterial BP monitorization (Spacelabs 90207) was performed before initiation of insulin treatment (time 0), 6 days after (time 1) and 1 year later (time 2). Moreover, ET-1 plasma levels were measured.

RESULTS

Insulin treatment did not produce any variation in systolic (124.3 +/- 11.6; 120.7 +/- 7.9; 127.0 +/- 13.4 mmHg) and diastolic (72.8 +/- 5.9; 71.5 +/- 3.4; 71.8 +/- 5.2 mmHg) 24-h BP monitorization at times 0, 1 and 2, respectively. The systolic and diastolic day/night differences did not change in the three times studied. Neither were significant differences observed in ET-1 plasma levels.

CONCLUSIONS

In patients with SFOH, insulin treatment did not induce any short- or long-term increase in BP or any variation in plasma ET-1 levels.

Cryopreservation of pancreatic islets prior to transplantation: a comparison between UW solution and RPMI culture medium

Effective cryopreservation of pancreatic islets would be valuable in several contexts: for the assessment of islet cell viability, the measurement of beta-cell function, and the maintenance of viability and sterility prior to islet transplantation. In this study, isolated rat islets were cryopreserved or not following overnight culture and the most suitable preservation solution for transportation between centers was sought. Unfrozen and frozen-and-thawed islets were allocated to each of four different groups: untreated controls; cultured overnight in RPMI at 37 degrees C; cold stored at 4 degrees C in RPMI for 18-24 h; and stored at 4 degrees C in University of Wisconsin (UW) solution for 18-24 h. The greatest cell viability, as assessed by ethidium bromide/acridine orange staining and image analysis, was observed when postthawed islets were cultured in RPMI, whereas the least viable samples were those that were stored in UW solution. Measurement of insulin content and secretion in static incubation assays using 2.8 and 16.7 mM glucose showed that all treated groups exhibited a significant insulin secretory response to glucose stimulation whereas the untreated frozen-thawed islets failed to show any response. The cryopreserved islets in each group were equally successful in reversing hyperglycemia in streptozotocin-treated allogeneic rats when grafted intraportally in sufficient numbers (2000-2500). The groups also showed a similar mean graft survival time of 6-7 days before rejection. However, the best experimental group (the postthaw cultured islets) failed to cure diabetic rats when grafted in a smaller numbers (<2000). These data demonstrate prompt and sustained function in cryopreserved islets when they were maintained by any of the methods studied if they were grafted in sufficient numbers. We conclude that cold storage of thawed cryopreserved islets using either RPMI or UW solution is an effective method for their transportation and/or storage, but does not reduce their immunogenicity before transplantation.

[Heart pathology of extracardiac origin. XI. Cardiac repercussions of diabetes mellitus]

Diabetes mellitus is one of the diseases with the greatest risk of developing coronary disease (CD), with the estimation of this risk in relation to the general population being from 2 to 4-fold greater. The existence of diabetes worsens the prognosis of CD and thus, postinfarction mortality in these patients is double that observed in non-diabetic patients. Together with the risk factors found in the general population, those of special interest are those derived from diabetes itself, such as hyperglycemia, dyslipemia, coagulation disorders and hyperinsulinemia or insulin resistance. Among these, the most important is probably the hyperglycemia which may contribute to the appearance of CD by different mechanisms such as proteic glycosylation, accumulation of sorbitol, increase in the synthesis of protein kinase C or oxidative stress. It must not be forgotten that an old controversy has recently been brought up suggesting that sulphonylureas may have a certain cardiotoxic effect, probably acting on the potassium channels dependent on ATP. Acute myocardial infarction in diabetic patients carries a greater risk of congestive heart failure, recurrent infarction, arrhythmia and cardiogenic shock, with one of its characteristics being the possibility of being silent when autonomic neuropathy is present. The prognosis of CD may be markedly improved by obtaining optimum glycemic control during the hours following infarction using intensified treatment. Diabetic myocardiopathy as a differentiated nosology responsible for alterations in myocardial contractile function and greater prevalence of heart failure in these patients seems to be clearly demonstrated although its etiology remains unknown.

Recurrence of immunological markers for type 1 (insulin-dependent) diabetes mellitus in immunosuppressed patients after pancreas transplantation

BACKGROUND

Type 1 (insulin dependent) diabetes mellitus (IDDM) is an autoimmune disease in which autoantibodies against islet cells develop concomitantly with or even preceding diagnosis. Because the recurrence of diabetes can be the cause of graft failure in patients with pancreas transplantation, we studied the possible recurrence of IDDM immunomarkers after transplantation.

METHODS

The following determinations were performed every 1-2 years after transplantation in 50 immunosuppressed IDDM patients with simultaneous kidney and pancreas transplantation (bladder drainage of exocrine secretion): islet cell antibodies (ICA) by direct immunofluorescence, antibodies against glutamic acid decarboxylase (GADab) by radiobinding assay, and the oral glucose tolerance test. The mean follow-up was 4.1+/-6.3 (range 1 to 9 years).

RESULTS

GADab were detected in 11 patients after transplantation, 10 of whom had been positive beforehand. ICA reappearance after transplantation was detected in seven patients (14%). The presence of ICA was related to GADab positivity (P=0.001) and HLA DR3 patients (P=0.04), but not with pancreatitis and rejection episodes, immunosuppression induction therapy, or donor HLA haplotype. During follow-up, an abnormal oral glucose tolerance test was more frequent in ICA-positive patients (P=0.02), with no differences in metabolic control or insulin secretion.

CONCLUSION

We conclude that GADab persist and ICA reappear despite immunosuppressive therapy in patients with functioning pancreas transplants. The relevance and the risk that this implies for IDDM development should be determined.

[Content of carbohydrates and trace elements in a group of non-alcoholic drinks]

BACKGROUND

In order to elaborate recommendations for the dietetic care of diabetic patients and other clinical disorders we have measured the concentration of carbohydrates and trace elements in a group of non alcoholic refreshments of current use in Spain.

MATERIAL AND METHODS

Thirty refreshments were classified into 10 groups. Glucose and phosphate were measured by hexokinase and reduction of phospho-molybdate methods respectively in an autoanalyzer Dax-72. Glucose and fructose were analyzed by cellulose thin-layer chromatography; glucose, fructose and sucrose by gas chromatographys. Sodium and potassium by emission spectrophotometry and calcium, magnesium, iron, copper and zinc by atomic absorption spectrophotometry.

RESULTS

Light refreshments and soft drinks have no carbohydrates. Isotonic beverages, fruit juices, cool tea and non alcoholic beers had less than 10 g/dl. Tonic waters, Fanta, different coles, non alcoholic bitter and others had more than 10 g/dl. Sodium levels between 15-20 mEq/l were found in the isotonic beverages and 7-Up and levels of 7 mEq/l in the others. Potassium values between 15-40 mEq/l were found in the fruit juices, 3-4 mEq/l in Gatorade and less than 1 mEq/l in the others.

CONCLUSIONS

Light refreshments and soft drinks contain low concentrations of carbohydrates and sodium. Fruit juices have high potassium concentration. Such information can be especially useful for dietetic care of diabetic patients.

[Prevalence of nephropathy in type I diabetes]

BACKGROUND

Diabetic nephropathy is a serious complication of diabetes, of which there are few epidemiological data in Spain. The aim of this study is to determine diabetic nephropathy prevalence in a group of patients with type I diabetes mellitus, representative of the population of Barcelona, Spain, evaluating several risk factors related with its development.

PATIENTS AND METHODS

639 patients (296 males and 343 women), from 6 hospitals, selected according with the diabetes duration (194 between 5 and 9 years [group I], 227 between 10 and 19 years [group II] and 218 with 20 years or more [group III]) were studied. In all patients urinary albumin excretion and plasma levels of creatinine, HbA1c, cholesterol and triglycerides were determined. The presence of retinopathy, neuropathy, vasculopathy and tobacco consumption were also evaluated.

RESULTS

The prevalence of diabetic nephropathy increased with longer diabetes duration (8.1% [CI: 4.3-11.9] in group I, 24.7% [CI: 19.1-30.3] in group II and 44.7% [CI: 38.1-51.3] in group III), as well as that of hypertension, diabetes complications, cholesterol and triglycerides plasma levels. Related to people with normal renal function, after logistic regression, microalbuminuria was associated with hypertension and longer diabetes duration. Clinical nephropathy (macroalbuminuria + renal failure) to hypertension, longer duration, hypertriglyceridemia, male sex and tobacco consumption.

CONCLUSIONS

The prevalence of diabetic nephropathy in Barcelona area is high and similar to that observed in other european regions. Its existence is associated with other diabetic complications. In addition to the classic risk factors, tobacco consumption must also be considered as a factor for diabetic nephropathy.

Effect of fusidic acid on pancreatic islet allograft rejection

We examined in fully mismatched rats, the survival of pancreatic islet allografts in recipients treated with either fusidic acid (FA), an antistaphyllococcal antibiotic that has been shown to possess an immunosuppressive effect in vitro and in vivo, or cyclosporin-A (CsA). Islets were isolated by collagenase digestion, separated from acinar tissue by handpicking under a dissecting microscope and transplanted into the liver by portal vein injection of streptozotocin(STZ)-induced diabetic rats. The results indicated that while a temporary immunosuppression with CsA achieved an indefinite islet allograft survival, FA administered to recipients daily was not able to prevent islet allograft rejection across a major histocompatibility barrier. We conclude that despite the fact that fusidic acid has been claimed to act as an-immunosuppressant drug in vitro with effects similar to those of CsA, unlike CsA, FA given either orally or by s.c. injection was not effective to prolong islet allograft survival in vivo.

Cyclosporine does not inhibit the process of revascularization of pancreatic islet transplantation

The immunosuppressive drug cyclosporin-A (CsA) has been widely used to prevent pancreatic islet allograft rejection. Because it has been suggested that CsA may inhibit the process of revascularization of transplanted islets, the purpose of the study was to analyze by a double indirect immunofluorescence technique the revascularization process of isolated islets grafted in the liver and in the renal subcapsular space of rats treated with immunosuppressive doses of CsA. Lewis rats were grafted with either Lewis (isografts) or Wistar (allografts) pancreatic islets obtained by collagenase digestion. Rats were killed at different days after implantation and the liver and kidney bearing the grafted islets were snap frozen and immunohistochemically stained with a double immunofluorescence technique using a rabbit antifactor-VIII antiserum (which labels endothelial cells) and a guinea pig antiinsulin antibody. Islets implanted into nonimmunosuppressed hosts completed revascularization by days 3-7 after transplantation, as shown by the detection of endothelial cells within and surrounding the islets. The identical staining pattern of revascularization was observed in nonrejecting allografts as well as in isografts treated with CsA. We conclude that CsA did not inhibit the process of revascularization of rat islets after free transplantation. This finding is relevant for human islet transplantation, where CsA is currently employed to prevent kidney and islet allograft rejection.

Follow-up study of the revascularization process of cryopreserved islets of Langerhans

Cryopreservation of islets of Langerhans is a necessary procedure since human pancreatic islet transplantation has become a reality for the clinical treatment of Type I, insulin-dependent diabetes mellitus. Although successful cryopreservation of rodent and human islets is a well-established technique for islet storage after isolation and purification, little is known about the influence of the freeze-thaw procedure on the islets' potential to induce angiogenesis and revascularization, a major process necessary for the viability of grafted cells. In this study, the revascularization process of cryopreserved islets transplanted in the liver and in the renal subcapsular space of diabetic and nondiabetic rats is analyzed by a double indirect immunofluorescence technique. Frozen-thawed pancreatic islets were cooled slowly to -40 degrees C, stored at -196 degrees C, and thawed rapidly. Lewis rat were grafted with either Lewis (isografts) or Wistar (allografts) overnight-cultured and frozen-thawed islets obtained by collagenase digestion. Rats were killed different days after implantation, and the livers and kidneys bearing the grafted islets were snap-frozen and immunohistochemically stained with a double immunofluorescence technique using a rabbit anti-factor VIII antiserum (which labels endothelial cells) and a guinea pig anti-insulin antibody. Overnight-cultured islet grafts completed revascularization by Days 4-7 after transplantation, as shown by the detection of endothelial cells within and surrounding the islets. The identical staining pattern of revascularization was observed in islets frozen-thawed before transplantation. It is concluded that islet cryopreservation is a suitable technique for long-term storage prior to transplantation since it does not interfere with the neovascularization process of islet grafts.

[Presence of markers predictive of type I pre-diabetes mellitus status in relatives of patients with type I diabetes mellitus]

BACKGROUND

The aim of this study was to analyze the predictive factors of IDDM in first degree relatives of IDDM patients.

SUBJECTS AND METHODS

From 1992 to 1994, 1,053 first degree relatives were screened for measuring islet cell antibodies (ICA) by indirect immunofluorescence (iFl). In all ICA positive subjects, beta cell function was analyzed by intravenous glucose tolerance test (IVGTT) and other immunologic parameters were also studied: anti-insulin antibodies (IAA) by radiobinding and antibodies to glutamic acid decarboxylase (GADAb) by ELISA methods.

RESULTS

ICA were found in 3.1% of the first degree relatives. IVGTT showed a significant decrease in acute first phase of insulin response to glucose (IRI 1 minute + 3 minute) in those with ICA > or = 20 JDF units. In patients with ICA > or = 20 JDF units, 20% were found to be positive for IAA and 40% were positive for GAdAb. Thirty-one percent (10/32) of ICA positive first degree relatives fulfilled prediabetes criteria. During follow-up, 40% (4/10) of these prediabetic patients developed IDDM.

CONCLUSION

This study confirms the possibility of identifying among first degree relatives of IDDM patients the subgroup with high risk of developing IDDM thus allowing the initiation of therapy for preventing or delaying IDDM onset.

Diabetes mellitus after liver transplantation: prevalence and predictive factors

AIMS/METHODS

To investigate the prevalence and risk factors for the development of diabetes mellitus after orthotopic liver transplantation, we reviewed 27 variables (including previous history of diabetes mellitus, data related to pre-transplant liver disease, and postoperative events) in 102 patients who survived longer than 1 year after orthotopic liver transplantation.

RESULTS

Fourteen patients had diabetes mellitus prior to liver transplantation and all but one were alive 2 and 3 years after transplantation, with all survivors continuing to have diabetes mellitus 1, 2 and 3 years after transplantation. Among the 88 patients without pre-transplant diabetes mellitus, the prevalence of post-transplant diabetes mellitus was 27% at 1 year, 9% at 2 years and 7% at 3 years, probably related to a significant reduction in the daily prednisone dose (13 +/- 4 mg at 1 year, 7 +/- 6 mg at 2 years and 2 +/- 4 mg at 3 years, p < 0.001). Patients with post-transplant diabetes mellitus 1 year after transplantation had a higher number of rejection episodes during the first postoperative year than those without post-transplant diabetes mellitus (1.5 +/- 1.1 vs 1.1 +/- 0.7, p < 0.05) and also had higher, but not statistically significant, cumulative steroid dose and blood cyclosporine levels. Mortality of patients with post-transplant diabetes mellitus was significantly higher during the second postoperative year in comparison with patients without post-transplant diabetes mellitus: 4/24 vs 2/64 (17% vs 3%; p < 0.05).

CONCLUSIONS

Liver transplantation does not significantly modify pre-transplant diabetes mellitus. Diabetes mellitus frequently develops de novo after liver transplantation, although this complication is usually transient and probably related to immunosuppressive drug administration. The prognosis of patients with post-transplant diabetes mellitus is worse than that of those without this complication.

Epidemiology of renal involvement in type II diabetics (NIDDM) in Catalonia. The Catalan Diabetic Nephropathy Study Group

The aim of this cross-sectional study was to establish the prevalence of renal involvement and to identify associations with its most important possible risk factors in a group of patients with Type II diabetes mellitus, representative of the population living in Catalonia. One thousand two hundred and three patients (47% males, mean age: 61 +/- 6 years, diabetes duration 9 +/- 6 years) were studied. Overnight urine samples were collected to determine urinary albumin excretion (UAE). If UAE was > 15 micrograms/min, a new 24-h urine collection for UAE measurement to establish the existence of microalbuminuria (20-200 micrograms/min) or macroalbuminuria (> 200 micrograms/min) was obtained. Clinic and metabolic evaluations were also performed. The prevalence (%) of microalbuminuria, macroalbuminuria and hypertension were, respectively, 23. 1, 5.4 and 42. In comparison with normoalbuminurics, patients with microalbuminuria were predominately male (P < 0.03), with a significantly higher systolic (P < 0.001) and diastolic (P < 0.001) blood pressure and body mass index (P < 0.001). The prevalence of smokers (former + current) was higher in patients with microalbuminuria (43 vs 32%, P < 0.025). Moreover, patients with nephropathy had more prevalence of retinopathy (P < 0.001), neuropathy (P < 0.001), peripheral angiopathy (P < 0.001) and coronary disease (P < 0.001). The prevalence of microalbuminuria in Type II diabetes in Catalonia is similar to that observed in other european countries. The existence of microalbuminuria is associated with several diabetic complications, as well as tobacco consumption and obesity.

[Retinopathy in patients with insulin-dependent diabetes mellitus of short duration]

To evaluate the role of metabolic control at the beginning of insulin-dependent diabetes mellitus (IDDM) in the development of diabetic retinopathy (DR) a cross-sectional study was performed with a retrospective analysis of 24 patients followed for at least seven years. The following parameters were investigated: 1) At IDDM diagnosis, age, sex, metabolic control (basal serum glucose, HbA1, cholesterol, triglycerides) and endogen insulin secretion (EIS). 2) At one year in the follow-up: EIS. 3) Since IDDM diagnosis and every 3-4 months: body mass index, dose and pattern of insulin administration and metabolic control. 4) At seven years in the follow-up: direct ophthalmoscopy, fluorescein angiography, microalbuminuria and blood pressure. In the seventh year of follow-up five patients (23.8%; 95% CI: 8.2%-47.2%) developed changes in fluorescein angiography secondary to IDDM. Compared with patients with normal fluorescein angiography their metabolic control was poorer (mean HbA1--seven years--: 11.7 +/- 0.5 versus 9.8 +/- 0.3%; p = 0.01); mean basal glycemia--seven years--: 214 +/- 13.3 versus 174 +/- 7.7 mg/dl; p = 0.03) and their systolic blood pressure (SBP) higher (124 +/- 5.5 versus 111 +/- 2.8 mmHg; p = 0.04). Logistic regression revealed that mean HbA1 values for seven years was the only independent risk factor significantly associated with the development of DR (p = 0.04). The conclusion is that in patients with IDDM of short duration, the development of DR is associated with a deficient glucose control and a higher SBP.

[Measurement of vibratory threshold in the diagnosis of diabetic neuropathy]

The usefulness of the quantitative measurement of vibration perception threshold (VPT) was assessed by a biothesiometer in the diagnosis of peripheral neuropathy in 36 patients with type I diabetes mellitus. The study included: a) clinical assessment (history and neurological examination); b) measurement of VPT at right metatarsus, right pretibial area and right metacarpus; c) electromiographical study (right peroneal, posterior tibial, right sural, right medial plantar); d) assessment of the autonomous nervous system (sympathetic and parasympathetic indexes); e) metabolic assessment (HbA1c at study and mean HbA1c in the previous year). The prevalence of peripheral neuropathy was 38%. VPT at metatarsal region in diabetic patients was higher than in controls (p < 0.05) and a positive correlation with evolution time of disease at metatarsal region (p < 0.05) and tibia (p < 0.05) was observed. Clinical symptoms and changes at examination correlated with VPT at metatarsus (p < 0.05) and tibia (p < 0.05). No relationship was observed between VPT and metabolic control. In conclusion, vibration threshold increases with evolution time in diabetes, but it was not influenced by metabolic control. Its measurement by a simple method, such as biothesiometer, could be useful in diagnosing peripheral neuropathy in clinically asymptomatic patients.