Telematic transmission of computerized blood glucose profiles for IDDM patients

OBJECTIVE

To improve the analysis of self-monitoring of blood glucose (SMBG) and its communication between patients and physicians by a telematic transmission of computerized SMBG and to study the consequences of its use on glucose control of insulin-dependent diabetic (IDDM) patients.

RESEARCH DESIGN AND METHODS

A prospective randomized crossover trial with two 3-mo periods, one with SMBG recorded on traditional booklets (booklet period) and another with computerized SMBG transmitted to a central data base through a telematic network (telematic period), comprised the study. During the latter phase, patients could receive computerized SMBG analysis on individual terminals connected to the telephone network (Minitel system). Blood glucose recordings and HbA1c were measured at inclusion and end of each period. Eleven pairs of IDDM patients on intensified insulin therapy were randomized within each pair to start with the telematic period (group A) or the booklet period (group B).

RESULTS

Telematic transmissions were successful (less than 1% failure rate). Although initial HbA1c was low (6.7%), it declined during the telematic period (delta = -0.41%) compared with the booklet period (delta = +0.37%, P = 0.05). The percentage of low (less than 3.3 mM) blood glucose values correlated with HbA1c changes during the telematic period (r = 0.714, P = 0.0014) but not the booklet period. The patients favored the telematic tool to analyze SMBG.

CONCLUSIONS

Telematic transmission of SMBG is feasible. It can improve SMBG analysis and perhaps glucose control, therefore offering a new way of communication between diabetic patients and their physicians.

Scotopization and the Nagel-II anomaloscope

The term scotopization refers to the intrusion of rod activity in colour vision when assessed under photopic observation conditions. Scotopization is an important symptom of cone dystrophies. The detection of scotopization is not easy. With the Nagel-II anomaloscope scotopization can be detected in two ways. One method is new and this method is described in the present paper.

Beta-cell cytoadherent lymphocytes in some subjects at risk for type 1 (insulin-dependent) diabetes: progression to diabetes within 2 years

The increased binding in vitro of CD3 CD4 T-lymphocytes from type 1 (insulin-dependent) diabetic patients to beta-cell membrane antigens compared to lymphocytes from control subjects was previously shown to be a marker of cell-mediated immunity, called diabetic rosettes. In the present study diabetic rosettes were detected in some subjects at risk for type 1 diabetes (first degree relatives of type 1 diabetic patients or nondiabetic subjects with previous transient hyperglycaemia). The mean number of lymphocytes adherent to beta-cells (beta-CL) was significantly higher in subjects at risk for type 1 diabetes than in age- and sex-matched control blood bank donors (P less than 10(-6]. This number of beta-CL was higher in type 1 diabetic patients than in subjects at risk (P less than 10(-6], and one-way analysis of variance by rank (Kruskal-Wallis) revealed that the three populations (controls, diabetics, and risk subjects) were different in terms of beta-CL values (P less than 0.001). The percentage of subjects at risk that had a positive test (arbitrarily defined as a beta-CL value higher than the 95th percentile of 228 controls) was 20%. No difference was observed between the two subgroups of subjects at risk in terms of either mean +/- SEM of beta-CL or percentages of individuals with a positive test. These diabetic rosettes were slightly associated with acute insulin response to iv glucose lower than the 5th percentile of controls (immunoreactive insulin at 1 +/- 3 min, 250 pmol/L; by chi 2, P = 0.04) and with HLA DR 3/4 heterozygosity (by chi 2, P = 0.04). They were not associated with islet cell antibodies (regardless of the threshold for positivity, expressed in Juvenile Diabetes Foundation units), insulin autoantibodies, activated (HLA DR+) T-lymphocytes, or sex. A statistical association was detected between HLA DR 3/4 heterozygosity and a low acute insulin response to iv glucose (by chi 2, P less than 0.003). The preliminary (2-yr) longitudinal follow-up revealed that out of five islet cell antibody-positive subjects who progressed to type 1 diabetes, three displayed beta-CL values higher than the 90th percentile of controls. Diabetic rosettes could, thus, be detected in some individuals at risk for type 1 diabetes as a marker of cell-mediated immunity.

[Urinary excretion of albumin and lipid abnormalities in hypertensive insulin-dependent diabetics]

Patients with insulin dependent diabetes mellitus (IDDM) often suffer from cardiovascular diseases as renal failure occurs. Elevated albumin excretion rate (AER) is a predictive value of this event. Relations between AER, blood pressure, serum lipids and apoproteins concentrations in 100 patients with IDDM have been surveyed. Twenty one hypertensive patients (HT group) were compared to 21 patients without hypertension (n HT group), matched for sex, age, diabetes duration, and metabolic control, assessed by glycosylated haemoglobin. Comparison of both groups showed HT group had elevated systolic blood pressure (137 +/- 12 vs 126 +/- 20 mmHg; p less than .05), elevated diastolic blood pressure (80 +/- 7 vs 71 +/- 8 mmHg; p less than .001), increase in AER (27 range 3-4023 vs 6 range 2-51 mg/day; p less than .001), slightly elevated serum creatinine (95 +/- 32 vs 78 +/- 15 mumol/l; p less than .05). In HT group, serum lipid composition showed: raise in total cholesterol (251 +/- 43 vs 221 +/- 41 mg/dl; p less than 0.5), elevated apoprotein B (130 +/- 30 vs 99 +/- 21 mg/dl; p less than .001) elevated apoprotein B/apoprotein A1 ratio (.91 +/- .32 vs .66 +/- .27; p less than .001), elevated triglycerides (157 +/- 53 vs 98 +/- 43 mg/dl; p less than .005) and elevated LDL-cholesterol (170 +/- 42 vs 143 +/- 33 mg/dl; p less than .05). Levels of apoprotein A1 and HDL-cholesterol were not significantly different. Body mass index, daily insulin requirement and tobacco usage were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical effects of calcium antagonists in hypertensive diabetics

The incidence of hypertension and coronary artery disease among diabetic patients is approximately two to three times greater than in nondiabetics. Recent evidence suggests that even moderately elevated blood pressure levels may result in diabetic complications involving the eyes or kidneys. However, treatment of diabetic patients with antihypertensive drugs may have a deleterious metabolic effect. Previous studies have suggested that calcium antagonists may reduce insulin secretion and therefore impair glucose tolerance. This has not been substantiated clinically; in general, it would appear that calcium antagonists have a minimal hyperglycemic effect. To establish whether interruption of excitation-contraction coupling in arterial smooth muscle and altered stimulus-secretion coupling occur at pharmacologically equivalent doses of calcium antagonist, the effect of nicardipine on insulin output and vascular resistance was studied in the isolated perfused rat pancreas and in eight hypertensive patients with impaired glucose tolerance during oral glucose tolerance testing (OGTT). Baseline insulin output in vitro was 86 +/- 22 ng/min at 8.0 mM glucose and 2.5 mM calcium. Application of 10 nM nicardipine reduced insulin output to 86% of baseline, whereas output was reduced to 16% by 1 microM nicardipine and to 6% by 10 mM nicardipine. Changes in duodenopancreatic outflow indicated maximal vasodilation of the pancreas at all three concentrations of nicardipine (10 nM-10 mM). In vivo nicardipine 30 mg t.i.d. for 2 weeks reduced systolic blood pressure from 168 +/- 2 mm Hg to 136 +/- 4 mm Hg (p < 0.001) and diastolic blood pressure from 96 +/- 3 mm Hg to 78 +/- 2 mm Hg (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular and insulinotropic effects of YC 170, a calcium agonist, on isolated perfused rat pancreas

To explore simultaneously the effects on insulin secretion and on vascular tone of YC 170, a new dihydropyridine derivative calcium agonist, isolated perfused rat pancreases were studied for insulin output and for duodenopancreatic resistances before, during and after exposure to YC 170 10(-4) M (n = 15) or its solvent (n = 10). Although insulin was stimulated transiently during the five first minutes following addition of YC 170 (p less than 0.01) the integrated insulin output measured during the whole experiments was not different with YC 170 from that observed with solvent. Conversely, the initial duodenopancreatic resistances (22 +/- 4 mmHg.ml-1.min-1) rose progressively with YC 170 up to maximal values at the end of experiments (104 +/- 28 mmHg.ml-1.min-1; p less than 0.01); no significant variation occurred with solvent. Vascular and insulinotropic effects of YC 170 can be dissociated, suggesting variable abilities to promote calcium transport across membranes of smooth muscle cells and of pancreatic B-cells.

Prevention of diabetic nephropathy with enalapril in normotensive diabetics with microalbuminuria

STUDY OBJECTIVE

To assess the effectiveness of inhibition of angiotensin converting enzyme in preventing diabetic nephropathy.

DESIGN

Randomised follow up study of normotensive diabetics with persistent microalbuminuria (30-300 mg/24 hours) treated with enalapril or its matched placebo for one year. Double blind for first six months, single blind for last six months.

SETTING

Diabetic clinic in tertiary referral centre.

PATIENTS

Treatment group and placebo group each comprised 10 normotensive diabetics with persistent microalbuminuria.

INTERVENTIONS

Treatment group was given enalapril 20 mg daily and controls matched placebo. Patients were given antihypertensive treatment after one year.

END POINT

Albumin excretion, arterial pressure, and renal function.

MAIN RESULTS

In last three months of trial three of 10 patients taking placebo had diabetic nephropathy (albumin excretion greater than 300 mg/24 hours). No patients taking enalapril developed nephropathy and five showed normal albumin excretion (less than 30 mg/24 hours) (p = 0.005, Mann-Whitney test). Mean arterial pressure was reduced by enalapril throughout study (p less than 0.005) but increased linearly with placebo (p less than 0.05). Albumin excretion decreased linearly with enalapril but not placebo. An increase in albumin excretion with placebo was positively related to the increase in mean arterial pressure (r = 0.709, p less than 0.05, Spearman's rank test). With enalapril total renal resistances and fractional albumin clearances improved progressively (time effect, p = 0.0001).

CONCLUSION

Inhibition of angiotensin converting enzyme prevents development of nephropathy in normotensive diabetics with persistent microalbuminuria. This may be due to reduction in intraglomerular pressure and to prevention of increased systemic blood pressure. Future studies should compare long term effects of inhibitors of converting enzyme with other antihypertensive drugs.

[Relations between arterial hypertension and diabetic nephropathy]

In insulin-dependent diabetics the course of the renal disease can be followed by measuring arterial blood pressure and urinary albumin excretion. Already at the stage of incipient nephropathy (microalbuminuria) a moderate but gradually increasing rise in blood pressure is noticeable. At the stage of patent nephropathy (macroalbuminuria) nothing but an effective antihypertensive treatment can slow down the deterioration of renal function and delay by a few years the occurrence of end-stage renal failure. When macroproteinuria or obvious arterial hypertension are present, it is much too late to institute an antihypertensive treatment. To really prevent diabetic nephropathy, this treatment must be given earlier, as soon as microalbuminuria is detected and irrespective of blood pressure values. Prescribing antihypertensive drugs, and especially angiotensin-converting enzyme inhibitors, seems to be the most effective way of reducing urinary albumin excretion. 6

[New antihypertensive therapy in diabetics]

According to the W.H.O. criteria (160/95 mmHg), arterial hypertension is present in about one third of diabetic patients. But the W.H.O. criteria are not appropriate in insulin-dependent diabetics. There is increasing evidence that a slight increase of blood pressure values may have a deleterious effect on various localizations of diabetic angiopathy. Arterial blood pressure is a major predictive factor for stroke or death due to coronary heart disease. The incidence and prevalence of diabetic retinopathy are significantly correlated with systolic and/or diastolic blood pressure values. In patients with incipient diabetic nephropathy, a slight elevation of blood pressure values is usually observed, an antihypertensive treatment may reduce albumin excretion rate and may prevent clinical diabetic nephropathy. Antihypertensive treatment is the more effective and the best tolerated of all interventions dedicated to reduce albumin excretion. Calcium antagonists and angiotensin converting enzyme inhibitors are at the present time the drugs to be used in the treatment of hypertensive diabetic patients as they are more effective and better tolerated than the usual antihypertensive agents. A part from their antihypertensive effect, they also improve cardiac, cerebral and intra-renal haemodynamics.

[Value of combined subcutaneous infusion of insulin and metformin in 10 insulin-dependent obese diabetics]

Combined continuous subcutaneous insulin infusion (CSII) and metformin (M) was tested in 10 overweighted insulin requiring diabetic patients (body mass index 27.9 +/- 4.9 kg/m2). They were still poorly controlled (HbA1 9.6 +/- 0.8%) despite large doses of lente insulin (Novo) (51.7 +/- 19.6 IU/24 h) injected once daily. With CSII after two weeks on placebo (P) they were enrolled in a randomized double blind cross-over trial with two successive one month periods of M (2550 mg/day) or P. At the end of the two-weeks period CSII--initial P, the daily regular insulin requirement decreased significantly (40.1 +/- 18.1). During M and P body weight and HbA1 were unchanged (respectively 28.6 +/- 6.0 vs 29.0 +/- 59 kg/m2 and 7.7 +/- 1.1 vs 7.7 +/- 0.8%). With M daily insulin requirements decreased significantly (32.0 +/- 16.8 vs 38.4 +/- 18.2 IU, p less than 0.05). During test-meals, M compared to placebo also reduced peripheral free insulin concentrations (-24.9 +/- 26.0%) while plasma glucose and C peptide remained comparable. In the conditions of this study, combined CSII and M reduced the insulin resistance observed in overweighted insulin requiring diabetic patients.

Converting enzyme inhibition and kidney function in normotensive diabetic patients with persistent microalbuminuria

The effects of a long term reduction in blood pressure on the kidney function of normotensive diabetic patients who had persistent microalbuminuria (30-300 mg albumin/24 hours) were studied in two groups of 10 such patients before and during six months of treatment with either 20 mg enalapril or placebo daily. Treatments were assigned randomly in a double blind fashion. Before treatment both groups had similar clinical characteristics, weight, diet, total glycosylated haemoglobin, median albumin excretion rate (enalapril group 124 mg/24 h, placebo group 81 mg/24 h), and mean arterial pressure (enalapril group 100 (SD 8) mm Hg, placebo group 99 (6) mm Hg). During treatment weight, urinary urea excretion, and total glycosylated haemoglobin remained unchanged. The mean arterial pressure decreased in the enalapril group but not in the placebo group (enalapril group 90 (10) mm Hg, placebo group 98 (8) mm Hg). The median albumin excretion rate also fell in the enalapril group but not in the placebo group (enalapril group 37 mg/24 h, placebo group 183 mg/24 h.) The glomerular filtration rate rose in the enalapril group from 130 (23) ml/min/1.73 m2 to 141 (24) ml/min/1.73 m2, and total renal resistances and fractional albumin clearance decreased while fractional albumin clearance increased in the placebo group. These results show that in patients who have diabetes but not hypertension a reduction in blood pressure by inhibition of converting enzyme for six months can reduce persistent microalbuminuria, perhaps by decreasing the intraglomerular pressure.

[Microalbuminuria in diabetics. II--Methodological aspects and therapeutic perspectives]

The screening for microalbuminuria in diabetic patients has been made possible by means of sufficiently sensitive and reproducible techniques. Threshold values of albumin excretion rate must be defined according to the type of urine collection and by taking into account the high variability of this parameter. The high variability of albumin excretion rate required that repeated measurements must be considered. The prevalence of microalbuminuria depends on the type of diabetes, the degree of micro- and macrovascular complications, and the presence of associated arterial hypertension. Current attempts to reduce microalbuminuria in the diabetic patients through strict glycaemic control, lowering of high blood pressure and other means, are discussed.

[Microalbuminuria in diabetics. I--Definition, significance and physiopathology]

The term "microalbuminuria" qualifies an albumin excretion rate above the upper limit of normal individuals but below values giving positive results with conventional test strips. Its predictive value has been established for diabetic nephropathy in type I Diabetes, and for an excessive risk for mortality in type II Diabetes. Microalbuminuria is of glomerular origin in diabetes. It is secondary both to intra-renal haemodynamic changes and to altered permeability of the glomerular basement membrane. The various parameters involved in its genesis are reviewed.

Effects of enalapril in insulin-dependent diabetic subjects with mild to moderate uncomplicated hypertension

The antihypertensive efficacy of enalapril and its effects on the metabolism and kidney function were investigated in 11 insulin-dependent diabetic subjects with uncomplicated mild to moderate hypertension. During a short-term single-blind controlled trial, one daily dose of 20 or 40 mg enalapril significantly reduced both systolic and diastolic blood pressure. In the supine position, mean systolic blood pressure declined from 169 +/- 6 to 142 +/- 6 mmHg (P less than .01) and mean diastolic blood pressure from 101 +/- 1.5 to 85 +/- 2 mmHg (P less than .001). No changes in heart rate or postural hypotension were observed. During 1 yr of treatment, the antihypertensive efficacy of enalapril did not decline, and no clinical side effects were observed. Inhibition by enalapril of angiotensin-converting enzyme did not modify daily insulin requirements, glycemic control, uricemia, or lipid metabolism; kalemia and the markers of diabetic nephropathy were not significantly altered. These results suggest that enalapril once daily should be used as the first step in the treatment of diabetic patients with mild to moderate hypertension.

Laser immunonephelometry for routine quantification of urinary albumin excretion

We describe a laser-immunonephelometric method for quantifying urinary albumin excretion (UAE) in large numbers of samples. For a 150-microL sample incubated at room temperature for 45 min with 40 microL of antiserum specific for human serum albumin, the assay range for albumin was 0.34 to 43.0 mg/L. For samples analyzed undiluted and diluted 10-fold, the range of measurable albumin was from 0.34 to 430.0 mg/L. With an automated version of this method, one can assay 240 samples per hour. Intra- and interassay CVs were less than 6% and 9%, respectively. Measurements by this method (y) correlated well with those obtained by a RIA method (x): y = 1.00x + 0.163 mg/L (n = 233; r = 0.996). The day-to-day CV for UAE was determined for three consecutive determinations done on each of 60 controls according to the time of collection and in 212 diabetics according to the amount of 24-h UAE. For controls, UAE was 8.0 +/- 8.1 mg/24 h (mean +/- SD), CV 44 +/- 23%. The CV was similar for diurnal (50 +/- 28%) and overnight (58 +/- 32%) collections from controls; and for diabetics with normal values for UAE: 35 +/- 32%, with slight albuminuria (25-300 mg/24 h):37 +/- 28%, or with macroalbuminuria (greater than 300 mg/24 h): 47 +/- 42%.

Laser immunonephelometry for routine quantification of urinary albumin excretion

We describe a laser-immunonephelometric method for quantifying urinary albumin excretion (UAE) in large numbers of samples. For a 150-microL sample incubated at room temperature for 45 min with 40 microL of antiserum specific for human serum albumin, the assay range for albumin was 0.34 to 43.0 mg/L. For samples analyzed undiluted and diluted 10-fold, the range of measurable albumin was from 0.34 to 430.0 mg/L. With an automated version of this method, one can assay 240 samples per hour. Intra- and interassay CVs were less than 6% and 9%, respectively. Measurements by this method (y) correlated well with those obtained by a RIA method (x): y = 1.00x + 0.163 mg/L (n = 233; r = 0.996). The day-to-day CV for UAE was determined for three consecutive determinations done on each of 60 controls according to the time of collection and in 212 diabetics according to the amount of 24-h UAE. For controls, UAE was 8.0 +/- 8.1 mg/24 h (mean +/- SD), CV 44 +/- 23%. The CV was similar for diurnal (50 +/- 28%) and overnight (58 +/- 32%) collections from controls; and for diabetics with normal values for UAE: 35 +/- 32%, with slight albuminuria (25-300 mg/24 h):37 +/- 28%, or with macroalbuminuria (greater than 300 mg/24 h): 47 +/- 42%.