Can management strategies alter the course of diabetic nephropathy?

End Stage Renal Disease (ESRD) is a common consequence of diabetic nephropathy (DN). DN is the major cause of death in patients with IDDM, accounting for greater than 40% of deaths with this form of diabetes. There is no clearly documented therapeutic technique that will prevent or reverse progressive renal damage in IDDM. While pancreatic transplantation and "cure" of diabetes in experimental animals may be associated with some histological reversal of renal pathology, this has not been documented in humans. Most studies agree that once diabetic renal disease is present (as documented by proteinuria), progression is inevitable, albeit the rate of progression may be altered by different therapeutic methods. There is considerable hope that "tight metabolic control" will prevent the initial damage that leads to DN and ESRD, but evidence remains inconclusive. There is some evidence that careful monitoring for microalbuminuria will allow for very early detection of damage and alterations in therapy. Our studies have documented a decrease in both morbidity and mortality in IDDM in patients who have been competitive athletes, suggesting that promotion of physical fitness may be a valuable means of delaying progression of renal disease while control of BP delays progression. Early detection and aggressive therapy is recommended. Some studies utilizing diets low in sodium and/or protein appear beneficial but more studies are needed before pediatric application.

Employment spectrum of IDDM

Occupational issues in 158 insulin-dependent diabetes mellitus (IDDM) individuals and 158 matched nondiabetic siblings were examined in a case-control design to evaluate the role of diabetes in the employability of people with IDDM. Overall, the IDDM cases were more likely to report refusal for a job at some point in their lives (56 vs. 42%, P = .02) than were the nondiabetic control siblings. Surprisingly, individuals who told job interviewers about their diabetes were more likely to report job refusal than their siblings (64 vs. 42%, P = .005), whereas individuals who did not mention their diabetes reported rates of refusal similar to their siblings (44 vs. 41%). IDDM cases were also less likely to be employed full time compared with siblings (55 vs. 73%, P = .001). Reduced employment in IDDM respondents was related to work disability. Reported work disability was more than seven times greater in the IDDM than the sibling group. The presence of diabetic complications was the primary factor related to work disability. Although 13% of IDDM respondents were unable to work because of disability, absenteeism among IDDM cases currently working did not differ from that of the nondiabetic siblings. Diabetes was not significantly associated with career levels or household income levels reported by the IDDM group. Disability, however, had a strong detrimental influence on these variables. The results suggest that hiring practices by employers may still be discriminatory toward individuals with IDDM. Once hired, the employment experiences of the IDDM population appear to be similar to the experiences of the nondiabetic population, provided the development of disabling diabetic complications has not taken place.

A comparison of high and low fat meals on postprandial esophageal acid exposure

Fatty foods have been identified as precipitating factors in symptomatic gastroesophageal reflux (GER). A fat meal has also been found to decrease lower esophageal sphincter pressure (LESP) in normal subjects. We used the ambulatory 24-h pH monitor to assess esophageal acid exposure in 10 normal subjects and 10 GER patients following low and high fat meals eaten in two body positions. The meals had nearly identical protein content, volumes, and calories. On successive days, patients ingested one of the meals twice, followed by random assignment to 3 h upright and 3 h recumbent position. Acid exposure for each hour over a 3-h postprandial (PP) period was assessed as the percent time pH less than 4.0. Increased upright acid exposure occurred in normals after the high fat (6.2 +/- 2.1%; mean +/- SE) compared with the low fat meal (1.5 +/- 0.5%; p less than 0.05). GER patients had greater (p less than 0.05) acid exposure than normals in all study periods, but no differences were found between low and high fat meals in either study position. High fat meals induce upright GER in normals, but do not significantly affect the abnormal amount of GER in patients. In addition, progressive increases in acid exposure were found over the 3 postprandial hours in GER patients in a recumbent position. The findings are consistent with prior data showing decreased LESP with a fat meal in normals.

Computer aided manual leucocyte differential counting

Over the last two decades numerous ways have been devised for automating the recording of the results of the leucocyte differential, ranging from computer-readable cards to very costly automated cell counters. The growing availability of inexpensive personal computers makes it possible to improve the counting and reporting of the manual differentials which still account for the bulk of these counts. This report describes the development of a system using a personal computer, either as a standalone device or integrated into a larger laboratory system, to assist the technologist in performing the differential count and in completely describing the results. It permits complete flexibility in function assignments and in information structuring to match the constraints of the laboratory host computer system.

Assessment of AlbuSure and its usefulness in identifying IDDM subjects at increased risk for developing clinical diabetic nephropathy

This study, which included 154 participants in a 10-yr follow-up study of diabetes complications, was conducted to evaluate AlbuSure (a qualitative test designed to detect urinary albumin concentrations greater than 0.03 g/L) for its ability to discriminate between albumin concentrations above and below the manufacturer's concentration threshold and to identify individuals at increased risk for developing diabetic nephropathy (i.e., those with albumin excretion rate [AER] greater than 0.0288 g/24 h). The reproducibility of AlbuSure results was also evaluated. The results of these evaluations were examined by three different types of urine collections (24 h, overnight, and timed postclinic) and overall. AlbuSure's validity was examined by comparing its results to immunonephelometrically measured concentrations and AER. When compared to albumin concentration, AlbuSure had an overall sensitivity of 81.8%, specificity of 94.8%, and positive predictive value of 90.6%. AlbuSure's sensitivity was lower (71.4%) when compared with AER; however, this was higher than the sensitivity achieved by dipsticks against AER (50.7%). On testing urine samples stored for 3 days at 4 degrees C, AlbuSure results were 100% reproducible after 1 day and had an overall reproducibility of 92% after 3 days. When urine was retested after 3 and 15 mo of storage at -70 degrees C, AlbuSure was greater than or equal to 90% reproducible, with some of the differing results attributable to corresponding changes in albumin concentration. The overnight sample appeared to be the sample of choice for testing with AlbuSure in that it showed excellent reproducibility and the highest sensitivity (compared to both albumin concentration and AER).

Clustering of premature mortality in 1,761 insulin-dependent diabetics and their family members

The clustering of premature mortality was investigated in 1,761 insulin-dependent diabetics and their family members from the Children's Hospital of Pittsburgh Insulin-Dependent Diabetes Mellitus Registry from 1950-1981. At follow-up, 5% of the mothers and 13% of the fathers were deceased. Life table analyses revealed that fathers of deceased diabetics were significantly more likely to die prematurely than fathers of living diabetics (18% vs. 8% at age 55 years; p = 0.02). A father-diabetic son concordance of mortality appeared to be responsible for this effect. A similar overall trend was observed for maternal mortality, although the difference was not statistically significant. Cause-specific analyses revealed that the increased paternal mortality was primarily the result of cardiovascular disease. Overall mortality rates of parents of deceased diabetics were higher than those of the general population, reaching statistical significance in the age group 35-44 years (p less than 0.05). Mortality among diabetic siblings was also examined. Diabetic siblings of deceased diabetics had a markedly increased risk of dying compared with diabetic siblings of living diabetics (p = 0.001). These findings indicate that premature mortality among both diabetic and nondiabetic relatives of diabetics clusters in families in which there is a deceased insulin-dependent diabetic, and suggest that the marked increase in mortality among persons with insulin-dependent diabetes may be partly under familial control.

Measuring diabetic neuropathy. Assessment and comparison of clinical examination and quantitative sensory testing

The need for a standardized and valid means of assessing diabetic neuropathy has been increasingly recognized. To identify potential components of such an assessment, interobserver variation (neurologist and internist) of a standard neurologic examination and the comparability of this examination with vibratory and thermal sensitivity testing was studied. The study population comprised the first 100 participants in a neuropathy substudy of 25- to 34-yr-old subjects with insulin-dependent diabetes mellitus taking part in a cohort follow-up study. Symptoms of dysesthesias, paresthesias, and burning, aching, or stabbing pain revealed good interobserver agreement. Signs of neuropathy, more prevalent in the great toe than index finger, showed poor interobserver agreement for vibration, but fair interobserver agreement for touch and pinprick. Mean quantitative sensory thresholds differed significantly by clinical category of abnormal vibratory and pinprick sensations. Threshold testing showed twice the prevalence of abnormality compared with clinical examination. It is concluded that components of the clinical examination can be identified that, along with quantitative sensory-threshold testing, may provide a satisfactory core assessment for use both in epidemiologic studies and incorporation into more in-depth protocols required for clinical research and practice. The clinical relevance of the greater prevalence of abnormalities on threshold testing will be established by long-term follow-up.

Choice of urine sample predictive of microalbuminuria in patients with insulin-dependent diabetes mellitus

Twenty-four-hour, four-hour (8 to 12 am), and overnight urine collections were examined for their ability to detect microalbuminuria in 292 patients with insulin-dependent diabetes mellitus (IDDM). Albumin excretion rate (AER) was measured and also estimated from the product of the urinary albumin/creatinine ratio (A/C) and the calculated 24-hour creatinine excretion. The fractional excretion of albumin (FEA) was also determined in aliquots from each urine sample. The correlation coefficients between measured 24-hour AER and estimated AER were 0.940 and 0.956 for four-hour and overnight collections, respectively (significance of each correlation, P less than 0.001). There was no advantage in using the FEA over the A/C ratio in predicting measured AER. Urinary A/C ratios (mg/mg) between 0.03 and 0.31 in the four-hour collections were highly predictive of microalbuminuria and of measured AER in the 24-hour collections: AER24-h (microgram/min/1.73 m2) = 2.74 + 0.870 x A/C4-h (all log10 values). In a subgroup of 175 patients having all three collections validated, 34 (20%) had microalbuminuria defined as AER 20 to 200 micrograms/min/1.73 m2 in at least two of the three samples and 44 (25%) had overt nephropathy (greater than 200 micrograms/min/1.73 m2). The ability of the AER in one urine collection to predict microalbuminuria in at least one of the other two collections was assessed in these 175 patients. Compared with the overnight urine collection, the four-hour collection had greater sensitivity while affording similar specificity and positive predictive value. Based on these data, the A/C ratio from a morning urine sample following initial AM voiding would seem adequate for the detection and monitoring of microalbuminuria in patients with IDDM.

Poisson regression modeling of temporal variation in incidence of childhood insulin-dependent diabetes mellitus in Allegheny County, Pennsylvania, and Wielkopolska, Poland, 1970-1985

Contradictory observations have accumulated regarding a secular trend and/or an epidemic pattern in the incidence of insulin-dependent diabetes mellitus. In this study, insulin-dependent diabetes mellitus incidence below age 15 years was examined in Allegheny County, Pennsylvania, and in Wielkopolska, Poland, two areas diverse in terms of their geography and average risk for this disease. Numerator data were extracted from individual patient records, and annual denominator data were available for the years 1970-1985. Poisson regression models were used to disentangle the contributions of country, race, sex, age, period, and cohort effects to the observed variation in incidence. Poles and Allegheny County nonwhites were at greatly and moderately reduced risk, respectively, relative to Allegheny County whites. An increase in risk with age was significant and proportional in all three groups. There was significant time variability in Wielkopolska, where an epidemic began in 1982 and continued through 1985. This was a period rather than a cohort phenomenon and was a result of a recent outbreak of the disease rather than a long-term trend. In Allegheny County, changes in risk over the 16-year period were insignificant, although incidence doubled among whites aged 0-9 years during 1982-1983. The Poisson regression modeling provided a quantification and formal comparison of determinants of the incidence of insulin-dependent diabetes mellitus.

Analyses on possible heterogeneity of IDDM based on presence of islet cell cytoplasmic antibody at diagnosis

In a large, representative sample of newly-diagnosed IDDM patients, using a highly sensitive assay to detect islet cell cytoplasmic antibodies (ICA), no marked differences were found between ICA+ and ICA- patients on various clinical, genetic, immunologic, and epidemiologic characteristics. In particular, there was no evidence for associations between ICA status at diagnosis and either sex, race, family history of IDDM, HLA-DR phenotype, antibody titers to Coxsackie B viruses, immunoglobulin levels, C-peptide and glycosylated hemoglobin concentrations, or insulin requirements. The most significant relationship was between the presence of ICA and a young age at diagnosis; however, the large overlap between the distributions of the ages at onset for ICA+ and ICA- groups on this variable suggests that this association is of limited importance. These data suggest that the presence or absence of ICA at diagnosis may not be useful in defining possible subtypes of IDDM.

Motor vehicle accidents and IDDM

A case-control study examining the 1-yr motor vehicle accident experiences of 158 insulin-dependent diabetes mellitus (IDDM) cases and 158 nondiabetic siblings was undertaken to evaluate the risk of motor vehicle accidents among drivers with IDDM. In multivariate analyses the overall accident risk of the cases and control subjects did not differ significantly. Female diabetic drivers, however, showed a marked increased risk for motor vehicle accidents. The accident risk among female cases was five times higher than among the female control subjects (P less than .05). Age and marital status were also significantly associated with accident probability in the multivariate model. The results suggest that IDDM could have an effect on the accident rate of diabetic drivers, particularly women. However, the traditional risk factors for automobile accidents, i.e., age and marital status, appear to have an equally strong influence on accident occurrence. Further studies are needed to 1) document the role of IDDM in accidents among representative samples of the IDDM population and 2) properly evaluate the licensing restrictions recommended for diabetic drivers.

Glucagon responses to hypoglycemia in children and adolescents with IDDM

To investigate plasma glucagon counterregulatory responses to hypoglycemia, an intravenous insulin bolus was given over 2 min to 73 children, aged 8.5-18.8 yr, with diabetes duration 1.2-17.1 yr. The plasma glucagon responses of the 61 children without glucagon antibodies or abnormal glucagon molecules were compared with those of 13 nondiabetic control subjects, aged 8.3-18.3 yr. Glucagon increments from baseline (73 +/- 10 pg/ml) and peak glucagon responses (212 +/- 13 pg/ml) were markedly lower in diabetic patients than in control subjects (341 +/- 49 and 462 +/- 51 pg/ml, respectively, P less than .001). Glucagon responses were found to correlate positively with the age of the patients at the time of testing (r = .478, P less than .001) and inversely with metabolic control as measured by glycosylated hemoglobin (r = -.342, P less than .02). There was no relationship between glucagon responses and diabetes duration. There was also no relationship between the glucagon increments and free-insulin levels during the test. Glucose recovery from the nadir was impaired in diabetic subjects compared with control subjects and correlated inversely with free-insulin levels. However, glucose recovery did not correlate with the rise of plasma glucagon. Glucose recovery was not different in patients with glucagon antibodies. In this study, we have demonstrated a deficient glucagon response to hypoglycemia in children with insulin-dependent diabetes mellitus. However, the clinical significance of this deficit is not clear.

Clinical consequences of deletion 1p35

Few cases of deletion 1p have been reported. We report a case of terminal deletion 1p35 in a patient with psychological and neurological dysfunction.

Evaluation of a new system for self blood glucose monitoring

A new combination reflectance meter/visually interpretable system (Glucometer II/Glucostix, Ames Division, Miles Laboratories, Elkhart, IN) has been designed for self blood glucose monitoring. Performance evaluation of this system demonstrates a linear relationship between meter-determined blood glucose values and laboratory-determined whole blood glucose values (y = 0.95x + 2.86, r = 0.97). In addition, 95% of visually interpreted blood glucose values are within one color block of YSI comparative values. Error grid analysis, a new method for determining the clinical accuracy of patient-determined blood glucose results, demonstrated that components of this new system produce clinically accurate blood glucose results.

Physical activity, insulin sensitivity, and the lipoprotein profile in young adults: the Beaver County Study

Higher levels of physical activity have been related to higher concentrations of high density lipoprotein (HDL) cholesterol and lower concentrations of triglycerides. To test the hypothesis that the association between physical activity and the lipoprotein profile is mediated at least in part through increased insulin sensitivity, the authors measured fasting serum levels of HDL cholesterol, triglycerides, insulin, and glucose in 87 men and 83 women (aged 20-24 years) from a population-based survey in Beaver County, Pennsylvania, in 1981-1982. An insulin sensitivity index was calculated as the reciprocal of the insulin and glucose product multiplied by 10,000. Univariate analysis among men indicates that HDL cholesterol was positively related to insulin sensitivity (r = 0.24, p less than 0.05) and to the physical activity score as assessed with Paffenbarger's questionnaire (r = 0.21, p less than 0.05). Insulin sensitivity and physical activity score were positively related (r = 0.14), although not significantly (p = 0.21). Triglycerides were inversely related to both physical activity (r = -0.22, p less than 0.05) and insulin sensitivity (r = -0.19, p = 0.07). No significant findings among women were noted. Multivariate results indicate that the relation between physical activity and the male lipoprotein profile is reduced after controlling for the effects of insulin sensitivity (p greater than 0.10). The authors conclude that in these young men the beneficial effect of physical activity is likely to be partially mediated by increased insulin sensitivity. The lack of findings among women suggests that sex hormones may influence the association between insulin sensitivity and lipoprotein lipids.

Sex differences in the coronary heart disease risk profile: a possible role for insulin. The Beaver County Study

The mortality rate from coronary heart disease is much higher among men than women except in diabetes mellitus, which appears to reduce this sex difference. It is hypothesized that the female advantage is due, at least partly, to the more efficient insulin mediated glucose homeostasis in females, an advantage lost in the diabetic state. The authors studied 170 young adult men and women aged 20-24 years from a population-based survey in Beaver County, Pennsylvania, in 1981-1982, in an attempt to further elucidate the sex-specific relationships between fasting serum insulin concentrations and several risk factors. Women who used oral contraceptives and subjects whose fasting serum glucose exceeded 110 mg/dl were excluded. Insulin was related to body mass index in both sexes (r = 0.31; p less than 0.01 for men; r = 0.26, p less than 0.01 for women) and to systolic blood pressure (r = 0.27, p less than 0.01 for men; r = 0.36, p less than 0.001 for women). Insulin was related to diastolic blood pressure in men only (r = 0.31, p less than 0.05). Multivariate analysis revealed fasting serum insulin to be an independent predictor of systolic blood pressure in both sexes and of diastolic blood pressure in men only. Insulin was inversely related to high density lipoprotein cholesterol only among men and this relationship appeared to be largely independent of body mass index and triglycerides. Results indicate that insulin concentration is associated with an adverse coronary heart disease risk factor profile especially among men, consistent with their excess risk of cardiovascular disease.

Residual beta-cell function in children with IDDM: reproducibility of testing and factors influencing insulin secretory reserve

Reproducibility of C-peptide secretion was assessed in 20 children (group 1) by their responses to two Sustacal- (a mixed liquid meal) stimulation tests performed 7-14 days apart. For the 12 C-peptide-positive children (basal C-peptide greater than or equal to 0.03 pmol/ml) there were no differences in the basal or stimulated values between tests 1 and 2. The effect of exogenous insulin on C-peptide secretion was assessed in 20 other children (group 2) by their responses to two Sustacal tests, one test without and one with soluble insulin (0.25 U/kg) injected subcutaneously before testing. Eleven children were C-peptide positive and had no differences in C-peptide response between tests 1 and 2. The results from test 1 in groups 1 and 2 were combined with those from 44 others undergoing a single Sustacal test (group 3, N = 84). There was a close correlation between basal and peak C-peptide concentrations in the 44 C-peptide-positive children (r = .88, P less than .001). Peak C-peptide concentrations correlated inversely with HbA1 (r = -.29, P less than .01), insulin dose in units per kilogram (r = -.40, P less than .001), and duration of diabetes (r = .33, P less than .001) and positively with age at onset of diabetes (r = .34, P less than .001). The C-peptide-positive children had reduced glucose response to Sustacal, lower HbA1 concentration, lower insulin requirement, later age of onset, and shorter duration of diabetes than children who were C-peptide negative.

Pittsburgh Insulin-Dependent Diabetes Mellitus Morbidity and Mortality Study: physical activity and diabetic complications

The long-term health consequences of chronic physical activity for patients with type I diabetes are unknown. In the current study, the association of physical activity to diabetic complications was assessed in 696 type I diabetic individuals diagnosed between 1950 and 1964. Participation in team sports in high school or college was not associated with a decreased prevalence of severe retinopathy or blindness later in life. There was, however, a suggestion of a negative association between physical activity and both cardiovascular disease and overall mortality, ie, individuals who participated in team sports were somewhat less likely to report macrovascular disease at follow-up or to have died than nonparticipants. The relationship between physical activity and diabetic complications only appeared in male subjects. The results suggest that activity early in life by patients with type I diabetes does not appear to be associated with an adverse health effect and may, in fact, be beneficial.

Height at diagnosis of insulin dependent diabetes in patients and their non-diabetic family members

Height at the onset of insulin dependent diabetes mellitus was evaluated in 200 newly diagnosed children, 187 non-diabetic siblings, and 169 parents. Diabetic children 5-9 years of age at diagnosis were consistently taller than the national average. Non-diabetic siblings of the same age were also tall. Diabetic children aged 14 or over at diagnosis were short, while their siblings and parents were of normal height. Diabetic children positive for islet cell antibodies were taller than those without islet cell antibodies. No association between height and HLA antigens was found. Non-diabetic siblings at high risk for the disease were closer in height to the diabetic children than were the lower risk, non-diabetic siblings. Siblings, particularly those under 10, were also significantly more obese than the general population. Deviations in growth in patients with insulin dependent diabetes mellitus appear to be related to age at diagnosis and a factor(s) not related to parental height.

Differences between blacks and whites in the epidemiology of insulin-dependent diabetes mellitus in Allegheny County, Pennsylvania

Racial differences in the incidence and natural history of insulin-dependent diabetes mellitus were evaluated in Allegheny County, Pennsylvania. The yearly incidence rate for whites was approximately 1.5 times that for blacks. The cumulative risk of developing insulin-dependent diabetes prior to age 20 was greater for whites (3.1/1,000, males; 2.8/1,000, females) than for blacks (1.7/1,000, males; 2.0/1,000, females). There was a slight excess risk for white males versus white females (relative risk = 1.09, p = 0.04), while no sex differential in risk was noted for blacks. The temporal trends and seasonal patterns were similar. Blacks more frequently possessed human lymphocyte antigen (HLA)-DR3/X and whites DR4/X; however, the risks associated with these antigens were similar by race. At onset, blacks had evidence of greater immunologic disturbance and less frequently reported infection than whites, although blacks more often had evidence of previous coxsackie viral infections. Evaluation of mortality patterns by race revealed that blacks had a higher mortality rate than whites. By 20 years duration of diabetes, blacks had a 2.4-fold increase in the risk of mortality compared with whites.

Growth hormone therapy for patients with Turner's syndrome

The linear growth of 8 patients with Turner's syndrome during human growth hormone (GH) administration was documented. Mean growth velocity was significantly greater during GH treatment (4.9 +/- 0.8 cm/year) than before treatment (3.3 +/- 0.8 cm/year, p less than 0.001). Growth velocity was related to dosage but not correlated with chronologic age, skeletal age or weight.

Glucose tolerance in siblings of type 1 diabetic patients: relationship to HLA status

In this report, we present an analysis of glucose and insulin responses during oral glucose tolerance tests in 369 siblings of Type 1 diabetic patients. All have been HLA typed at the A, B and C loci. Though most had normal glucose tolerance by National Diabetes Data Group criteria (92% of the males and 95% of the females), siblings who shared both HLA haplotypes with the diabetic patient in the family had higher mean 3-hour glucose areas than those who shared one or neither HLA haplotype (p less than 0.01). This difference was more marked in males and older siblings. Insulin concentrations did not differ significantly between the two groups except that, for those aged less than 16 years, the group sharing both haplotypes had lower fasting insulin concentrations (p = 0.05); for 16-29 year olds, the corresponding group had marginally higher 3-hour insulin areas than the remainder of siblings (p = 0.17). Little association with specific haplotypes (A1B8 or A2B15) was seen. Multivariate analyses, adjusting for age and obesity, eliminated the 3-h glucose difference in females by HLA sharing status (p = 0.37) although in males it remained significant (p less than 0.001). Failure to account for age, sex and obesity may explain some of the conflicts in the reported literature. The glucose tolerance differences seen by HLA haplotype sharing status did not correlate with the presence of anti-islet cell antibodies. These results are consistent with the hypothesis that the HLA identical siblings, particularly males, have different (i.e. worse) glucose tolerance than their haploidentical and non-HLA identical siblings.

Effects of improved glycemic control on microalbuminuria in adolescents with insulin-dependent diabetes mellitus

The effect of improved glycemic control on microalbuminuria was evaluated longitudinally in 13 adolescents with insulin-dependent diabetes mellitus (IDDM) of 8.4 +/- 0.8 years duration. Glycemic control and microalbuminuria were assessed under three treatment regimens: conventional therapy (Period A); after 6 weeks of intensified conventional therapy (Period B); and at three periods during continuous subcutaneous insulin infusion (CSII) (Period C = 10-14 days, Period D = 2-4 months, and Period E = 6-8 months, of CSII). Although euglycemia was not achieved, there was a decrease in mean 24-hour blood glucose concentrations measured hourly in the hospital, with values averaging 239 mg/dl in Period A, 202 mg/dl in Period B, and 156-184 mg/dl in Periods C to E. This was accompanied by significant reductions in the values for whole blood, and to a lesser extent, in stable glycosylated hemoglobin A1 (GHbA1) (p less than 0.05), but not in creatinine clearance, albumin clearance, or in albumin excretion rate. Significant correlations were found between whole blood GHbA1 levels and albumin clearance in each of Periods B to E and between albumin clearance and albumin excretion in Periods B to D (p less than 0.05) but not in Period A. Our data suggests that the degree of improvement in glycemic control obtained in our adolescent population with IDDM using either intensive conventional therapy or CSII does not reduce the microalbuminuria. If modulation of microalbuminuria is achievable it may require euglycemia or may involve other factors which have a more direct effect on the transit of albumin across the glomerular basement membrane.