Acute postchallenge hyperinsulinemia predicts weight gain: a prospective study.

The relationships of insulin secretion and insulin action to body weight are incompletely understood. Obesity is associated with reduced sensitivity to insulin and high fasting and postprandial serum insulin levels. However, it is unknown whether insulin secretion rises to compensate for insulin resistance or high insulin secretion promotes body weight gain and the development of insulin resistance. To shed light on this question, we examined weight gain over an interval of 16.7 +/- 3.9 years (mean +/- SD) in 107 glucose-tolerant offspring (48 men, 59 women) of two parents with NIDDM. The offspring had a baseline intravenous glucose tolerance test, at which time they were aged 32.9 +/- 9.7 years, and only those who did not develop diabetes during the follow-up period were included. We estimated insulin sensitivity with the insulin sensitivity index from Bergman's minimal model of glucose disposal and acute insulin secretion from the incremental area under the insulin curve in the first 10 min of the intravenous glucose tolerance test. Weight-gain rate (g/year) was defined as the regression slope of each subject's body weight over time. High acute insulin secretion, young age, and low baseline percent ideal body weight (IBW) were each associated with a high rate of weight gain. After adjustment for differences in age and IBW, statistically significant effects of insulin sensitivity (P = 0.05) as well as acute insulin secretion (P = 0.001) were obtained. To estimate the effects of acute insulin secretion and insulin sensitivity on the average rate of weight gain (adjusting for age and IBW), the study group was stratified into four subgroups by dividing it at the medians of these two variables. Among those with low acute insulin secretion, weight-gain rate was the same regardless of whether insulin sensitivity was low or high (176 and 152 g/year, respectively). Among those with high acute insulin secretion, mean weight-gain rate was still rather low in those with low insulin sensitivity (271 g/year), but it was quite high in those with high insulin sensitivity (672 g/year; significantly higher than in all other subgroups). Therefore a high first-phase insulin response to intravenous glucose is a risk factor for long-term weight gain, and this effect is particularly manifested in insulin-sensitive individuals.

Natural history of impaired glucose tolerance: follow-up at Joslin Clinic.

The goal of this study was to examine follow-up data on the offspring of two parents with NIDDM who have IGT to identify predictors of progression to NIDDM. The study group consisted of 80 individuals with IGT (WHO criteria), 28 of whom had IGT at baseline, and 52 who developed it during follow-up. Both an oral glucose tolerance test (OGTT) and an intravenous glucose tolerance test (IVGTT) were performed at baseline. After a median follow-up interval of 8 years, 35% had progressed to NIDDM, 37% had reverted to normal glucose tolerance, and 29% still had IGT. Those who progressed were younger and more obese than non-progressors. Glucose and insulin values from the OGTT that established the diagnosis of IGT were analysed by multiple logistic regression to determine which time points best discriminated between progressors and non-progressors. High insulin, but not glucose, values at 0 and 120 min distinguished progressors from non-progressors. Values at other sample times that were significantly different (p < 0.05) in progressors were: higher glucose values at 30, 45, and 60 min and higher insulin values at 90 and 180 min. Multiple logistic regression analysis of Bergman's minimal model parameters obtained from the IVGTTs performed at baseline demonstrated that, once IGT is established, low acute phase insulin secretion as well as low insulin sensitivity are significant predictors of progression to NIDDM.

Late progression to diabetes and evidence for chronic beta-cell autoimmunity in identical twins of patients with type I diabetes.

Previous studies suggest that after 6 years of discordance, identical twin pairs rarely become concordant for type I diabetes. With up to 39 years of follow-up from the onset of diabetes in the index twin, we determined how many discordant twins have evidence of beta-cell autoimmunity and how many develop overt diabetes. We longitudinally followed 23 pairs of identical twins (or triplets) that were selected from a total group of 30 pairs because they were discordant for type I diabetes when first ascertained. Seven developed diabetes after 3, 3, 7, 8, 9, 31 and 36 years of discordance. By survival analysis, the concordance after 10 years from the onset of diabetes in the index twin was estimated as 23% (95% confidence interval, 5-40%), increasing to 38% (95% confidence interval, 8-69%) after 31 years. Among 16 twins remaining nondiabetic at last follow-up (8-39 years of discordance), 12 were assessed with serial intravenous glucose tolerance tests and a total of 407 measurements by radioassay of antibodies against three defined autoantigens (glutamic acid decarboxylase, insulin, and the recently cloned molecule ICA512). Two-thirds (8 of 12) had evidence of beta-cell autoimmunity (persistently positive autoantibody levels) and/or first-phase insulin release less than the 1st percentile of control subjects. In summary, identical twins may develop diabetes after a prolonged period of discordance and approximately two-thirds of long-term discordant twins have evidence of persistent beta-cell autoimmunity and/or beta-cell damage. The concordance for beta-cell autoimmunity, therefore, is much higher than for overt diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of glucose and insulin resistance in development of type 2 diabetes mellitus: results of a 25-year follow-up study.

Type 2 diabetes mellitus is characterised by resistance of peripheral tissues to insulin and a relative deficiency of insulin secretion. To find out which is the earliest or primary determinant of disease, we used a minimum model of glucose disposal and insulin secretion based on intravenous glucose tolerance tests to estimate insulin sensitivity (SI), glucose effectiveness (ie, insulin-independent glucose removal rate, SG), and first-phase and second-phase beta-cell responsiveness in normoglycaemic offspring of couples who both had type 2 diabetes. 155 subjects from 86 families were followed-up for 6-25 years. More than 10 years before the development of diabetes, subjects who developed the disease had lower values of both SI (mean 3.2 [SD 2.4] vs 8.1 [6.7] 10(-3) I min-1 pmol-1 insulin; p < 0.0001) and SG (1.6 [0.9] vs 2.3 [1.2] 10(-2) min-1, p < 0.0001) than did those who remained normoglycaemic). For the subjects with both SI and SG below the group median, the cumulative incidence of type 2 diabetes during the 25 years was 76% (95% confidence interval 54-99). By contrast, no subject with both SI and SG above the median developed the disease. Subjects with low SI/high SG or high SI/low SG had intermediate risks. Insulin secretion, especially first phase, tended to be increased rather than decreased in this prediabetic phase and was appropriate for the level of insulin resistance. The development of type 2 diabetes is preceded by and predicted by defects in both insulin-dependent and insulin-independent glucose uptake; the defects are detectable when the patients are normoglycaemic and in most cases more than a decade before diagnosis of disease.

Familial clustering of insulin sensitivity.

This study's objective was to determine whether there is familial clustering of insulin sensitivity (SI) or insulin-independent glucose uptake (SG), which would be evidence that they are genetically determined traits. Outpatients had a 3-h intravenous glucose tolerance test. Nondiabetic individuals (n = 183), ranging in age from 16 to 60 yr, were from 105 families that had 2 parents with non-insulin-dependent diabetes mellitus. Of these families, 62 contributed 1 offspring, 21 contributed 2, 13 contributed 3, 6 contributed 4, and 2 and 1 contributed 5 and 6, respectively. The minimal model of glucose disposal and the glucose and insulin values from the intravenous glucose tolerance tests were used to estimate SI and SG. The intraclass correlation coefficient was used to compare the within-family variability of SI and SG with the respective between-family distributions. The intraclass correlation coefficients were 0.26 (P = 0.008) for SI and 0.081 (P = 0.45) for SG. SI and SG were uncorrelated (r = -0.059, P = 0.42). The intraclass correlation of SI could not be explained by familial clustering of fasting insulin or ideal body weight. Finally, the 10 families with the lowest values of SI had a significantly higher within-sibship variability of SI than the other 33 families (P less than 0.001, F test). SI but not SG showed familial clustering, which is consistent with a polygenic determinant of SI. In addition, a large within-family variability of SI in some families is compatible with a major gene effect with a dominant mode of inheritance.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostically significant heterogeneity of cytoplasmic islet cell antibodies in relatives of patients with type I diabetes.

A significant proportion of relatives of patients with insulin-dependent (type I) diabetes with high titers of cytoplasmic islet cell autoantibodies (ICAs) do not progress to overt diabetes with up to 8 yr of follow-up. This may reflect that follow-up of such relatives has not been long enough to observe diabetes, that despite expression of identical ICAs, some relatives will not progress to diabetes; or that there is heterogeneity in what is identified as ICA. We identified a subset of ICA that was restricted in its species (not reacting with mouse islets) and cell-type reactivity within islets (beta-cell specific). Only one of eight relatives whose sera had the restricted pattern of reactivity progressed to overt diabetes, and on sequential evaluation, all but the one relative who progressed to diabetes have maintained normal first-phase insulin secretion to intravenous glucose. In contrast, by life-table analysis, 70% of relatives expressing nonrestricted ICA became diabetic within 5 yr of follow-up (1 of 8 vs. 16 of 25 diabetic at last follow-up, P less than 0.02). Moreover, preliminary data suggest a significant association of the human leukocyte antigen DQB1*0602 allele of DR2 haplotypes with the restricted ICA pattern (4 of 5 DQB1*0602 restricted vs. 0 nonrestricted ICA, P = 0.006). We propose that expression of a genetically determined restricted ICA pattern confers a markedly lower risk for progression to diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)

Specific association of HLA-DR4 with increased prevalence and level of insulin autoantibodies in first-degree relatives of patients with type I diabetes.

First-degree relatives of patients with insulin-dependent (type I) diabetes (n = 264 from 106 families) were evaluated with HLA typing and determination of competitive insulin autoantibodies (CIAAs) and islet cell autoantibodies (ICAs). The levels of CIAAs in 30 relatives exceeded our upper limit of normal (greater than or equal to 39 nU/ml), and 30 had high-titer ICAs (greater than or equal to 40 Juvenile Diabetes Foundation units [JDF U]). Eleven of the HLA-typed relatives developed diabetes during follow-up. Twenty-three percent (28 of 123) of the relatives with at least one HLA-DR4 allele were CIAA+ (CIAA greater than or equal to 39 nU/ml) versus 4% (6 of 141) among DR4- relatives (P less than 0.0001). Twenty-one of 22 of the highest CIAA values were all in the DR4+ group (DR4+ vs. DR4-, P = 0.003, Wilcoxon's rank-sum test). HLA-DR3 did not correlate with the level of CIAAs, and neither DR3 nor DR4 correlated with titer of ICAs measured in JDF U. We conclude that, in first-degree relatives of patients with type I diabetes, there is a striking association with HLA-DR4 in both the prevalence of relatives exceeding the normal CIAA range and in the level of CIAAs. These data suggest that a gene on HLA-DR4 haplotypes contributes to the level of anti-insulin autoimmunity, and we hypothesize that DR4-associated diabetes susceptibility, distinct from DR3-associated susceptibility, may be secondary to this influence.

Slow glucose removal rate and hyperinsulinemia precede the development of type II diabetes in the offspring of diabetic parents.

OBJECTIVE: To determine whether insulin resistance or insulin deficiency is primary in the pathogenesis of type II diabetes. DESIGN: Cohort analytic study of persons with normal glucose tolerance but with a high risk for developing type II diabetes (average follow-up time, 13 years). SETTING: Outpatients had an intravenous glucose tolerance test and were contacted periodically to ascertain diagnoses of diabetes. PARTICIPANTS: One hundred and fifty-five normal offspring, ranging in age from 16 to 60 years, of two parents with type II diabetes and 186 normal control subjects in the same age range who had no family history of diabetes. MEASUREMENTS AND MAIN RESULTS: Two phenotypic characteristics distinguished the offspring of diabetic parents from control subjects. They had slower glucose removal rates (Kg) (P less than 0.01) and higher insulin levels (fasting and during the second phase of insulin response to intravenous glucose; P less than 0.0001) than did control subjects, even after adjustment for differences in obesity. Sixteen percent of the offspring developed type II diabetes. Mean Kg at baseline was 1.7%/min among offspring who subsequently developed diabetes, 2.2%/min among offspring who remained nondiabetic, and 2.3%/min among control subjects. Corresponding means for first-phase insulin were 498, 354, and 373 pM, respectively, whereas second-phase insulin means were 329, 117, and 87 pM, respectively. In multivariate analysis, low Kg and high serum insulin levels independently increased the risk for developing diabetes among the offspring of diabetic parents. CONCLUSIONS: One to two decades before type II diabetes is diagnosed, reduced glucose clearance is already present. This reduced clearance is accompanied by compensatory hyperinsulinemia, not hypoinsulinemia, suggesting that the primary defect is in peripheral tissue response to insulin and glucose, not in the pancreatic beta cell.

Predicting type I diabetes.

Currently, there are three markers that are being studied with the potential to give a high positive predictive value for the development of type I diabetes (insulin-dependent diabetes caused by autoimmune beta-cell destruction) and that can be utilized to predict the disease in susceptible relatives: 1) high-titer cytoplasmic islet cell antibodies, 2) insulin autoantibodies detected with fluid-phase radiobinding assays, and 3) first-phase insulin release after intravenous glucose less than 1st percentile. With the combination of these assays, it seems to be possible to identify first-degree relatives with a high probability of developing type I diabetes within a limited time span (i.e., less than 10 yr). The ability to predict type I diabetes with selected assays will allow trials for prevention of diabetes and trials to assess whether prediction will decrease morbidity and mortality at onset of diabetes.

Analysis of metabolic progression to type I diabetes in ICA+ relatives of patients with type I diabetes.

We intensively studied 5 islet cell-antibody-positive (ICA+) first-degree relatives of type I (insulin-dependent) diabetic patients before overt diabetes. In total, 55 intravenous glucose tolerance tests (IVGTTs) and 83 fasting plasma glucose determinations were made over a maximum 4-yr period before diabetes. The 5 prediabetic relatives (not diabetic when initially studied but subsequently progressed to overt diabetes) as a group showed a progressive rise in fasting glucose (r = 0.58, P less than 0.001, slope = 23.1 mg.dl-1.yr-1) and glucose at 60 min in IVGTT (r = 0.46, P = 0.01, slope = 47.5 mg.dl-1.yr-1) beginning 1.5 yr before diabetes. During the 4.0- to 1.5-yr period before overt diabetes, no change was observed in fasting glucose or glucose at 60 min on IVGTT (fasting glucose: r = 0.21, P = 0.18, slope = 2.1 mg.dl-1.yr-1; 60-min glucose: r = 0.08, P = 0.72, slope = 2.9 mg.dl-1.yr-1). The positive predictive value for a fasting glucose greater than 108 mg/dl to be within 1.5 yr of diabetes was 100% (11 of 11 values). The negative predictive value of a stimulated insulin (1-min + 3-min insulin - 2 X basal insulin) level greater than 24 microU/ml to be greater than 1.5 yr from diabetes was 90% (9 of 10 values) and 100% (10 of 10 values) at greater than 1 yr from overt diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term results of pancreatic resection and segmental pancreatic autotransplantation for chronic pancreatitis.

Thirteen patients who underwent extensive pancreatic resection and segmental autotransplantation and who have a median follow-up of 62 months are presented. Eleven patients had technically successful grafts. Three of six patients who underwent total pancreatectomy and three of five patients who underwent near-total resection remain insulin-independent. Those patients who require insulin require small doses and have stable diabetes. Pain has recurred in 7 of the 11 patients who underwent distal subtotal resection; 5 of them required pancreatoduodenectomy and completion pancreatectomy for pain relief. Because of the high rate of recurrence of pain after distal resection, we favor pancreatoduodenectomy as the initial procedure of choice. When distal near-total or total pancreatectomy is required, the addition of segmental autotransplantation offers definitive, although at times transient, benefits in glucose homeostasis compared with no transplantation.

Life-table analysis of progression to diabetes of anti-insulin autoantibody-positive relatives of individuals with type I diabetes.

Cytoplasmic islet cell antibody-negative (ICA-; less than 20 Juvenile Diabetes Foundation units, n = 1670) and ICA+ (n = 42) first-degree relatives of type I (insulin-dependent) diabetic individuals were studied for competitive insulin autoantibodies (CIAAs) with a radioassay. Overall, 3.7% of first-degree relatives (64 of 1712) were CIAA+. Of ICA- relatives, 2.7% (45 of 1670) exceeded the upper limit of our normal CIAA range (greater than 39 nU/ml), and 45% (19 of 42) of ICA+ relatives exceeded this normal range. Follow-up serums for repeat CIAA determination have been obtained from 16 of the nondiabetic CIAA+/ICA- individuals (time between samples, 0.4-5.8 yr). Fourteen of these 16 (87%) CIAA+/ICA- relatives were found to still be positive on follow-up, and 2 of the relatives who were positive on the first determination were negative on their follow-up test. With a mean follow-up of approximately 2 yr, 4 of 45 (9%) of the CIAA+/ICA- relatives, 5 of 23 (22%) of the ICA+/CIAA- relatives, and 12 of 19 (63%) of the CIAA+/ICA+ relatives developed diabetes. Life-table analysis indicated that, overall, 53% of CIAA+ relatives become diabetic after 5 yr of follow-up versus 65% of ICA+ relatives. Also by life-table analysis, the predicted risk after 5 yr of follow-up for progression to diabetes is 17% for CIAA+/ICA- relatives, 42% for ICA+/CIAA- relatives, and 77% for CIAA+/ICA+ relatives. The highest rate of progression to diabetes was found in ICA+ relatives with CIAA levels greater than 150 nU/ml (100% projected to be diabetic within 5 yr, P less than .008 vs. ICA+/CIAA- relatives).

Production of insulin antibodies by mice rejecting insulin transfected cells.

Antibodies to insulin appear prior to the development of Type I diabetes and their concentration may correlate with the rate of autoimmune beta cell destruction. In order to study potential mechanisms involved in the production of antibodies to insulin, we transplanted different strains of mice with histoincompatible non-islet cells (AtT20-Ins and NIH-3T3-Ins) synthesizing homologous insulin, in contrast to immunization with non-transfected cells and insulin in Freund's adjuvant. The pituitary cell line (AtT20) and the fibroblast cell line (NIH-3T3) were transfected with the rat insulin-II gene (which encodes an insulin molecule identical to that of mouse insulin-II). No antibodies to insulin were found after subcutaneous injection of AtT20-control cells (without the integrated rat insulin gene) or after injection of rat insulin complete Freund's adjuvant. After subcutaneous injections of living AtT20-Ins or NIH-3T3-Ins cells producing insulin (40 to 60 ng insulin/10(6) cells per injection) in two strains (BALB/cJ, C3H/HeJ) but not in a third (SJL/J), antibodies to insulin rapidly appeared. In addition, when AtT20-Ins cells were transplanted into Wistar-Furth rats, insulin antibodies appeared in three out of four animals. The level of antibodies induced was similar to the concentrations of insulin antibodies of prediabetic NOD mice. This finding suggests that during the immune destruction of a cell synthesizing insulin, humoral 'tolerance' to insulin can be rapidly abrogated. Genetic control of this response is suggested by the difference between response of BALB/cJ and C3H/He vs SJL/J.

First-trimester hemoglobin A1 and risk for major malformation and spontaneous abortion in diabetic pregnancy.

The relationship between the level of hemoglobin A1 (Hb A1) in the first trimester and major malformations and spontaneous abortions was examined in 303 insulin-requiring diabetic gravidas. During the study period, all patients with insulin-requiring diabetes mellitus antedating pregnancy who registered for prenatal care prior to 12 weeks' gestation and who had a known outcome were included. Thirty-five percent of the patients entered with a first-trimester Hb A1 of greater than 11.0% of total hemoglobin (9 standard deviations above the mean for a nondiabetic population). A broad spectrum of glycemic control was therefore represented. The risk of spontaneous abortion was 12.4% with first-trimester Hb A1 less than or equal to 9.3% and 37.5% with Hb A1 greater than 14.4% (risk ratio 3.0; 95% confidence interval 1.3-7.0). The risk for major malformation was 3.0% with Hb A1 less than or equal to 9.3% and 40% with Hb A1 greater than 14.4% (risk ratio 13.2; 95% confidence interval 4.3-40.4). Although the risks for both adverse outcomes were markedly elevated following a first trimester in very poor metabolic control, there was a broad range of control over which the risks were not substantially elevated. To keep malformations and spontaneous abortions to a minimum among diabetic women does not require "excellent" control; there seems to be a fairly broad range of "acceptable" control.

Radioassay determination of insulin autoantibodies in NOD mice. Correlation with increased risk of progression to overt diabetes.

In an initial cross-sectional study, 29 female and 25 male nondiabetic weaned nonobese diabetic (NOD) mice of various ages (age range 30-300 days, mean 108 +/- 10 days) and 11 unweaned NOD pups were evaluated for competitive insulin autoantibodies (CIAAs) with a fluid-phase radioassay. Eleven of 54 (20%) weaned NOD mice had CIAA levels above the range (greater than 39 nU/ml) of 81 control mice. The group of NOD mice that progressed to diabetes had a significantly higher level of CIAAs than NOD mice that did not progress to diabetes (NOD mice progressing to diabetes: CIAA 63 +/- 12 nU/ml; NOD mice not progressing to diabetes: CIAA 8 +/- 4 nU/ml; P less than .02). Seven of 11 (64%) NOD mice having CIAA concentrations exceeding the normal range progressed to diabetes, whereas only 4 of 43 (9%) NOD mice progressed to diabetes without detection of elevated CIAAs (Fisher's exact test, P less than .0005). The relative risk of progressing to overt diabetes with CIAA levels greater than 39 nU/ml was therefore 17 (P less than .005), giving a positive predictive value of 64%, a negative predictive value of 91%, and an overall accuracy of 85%. None of 11 unweaned NOD pups had CIAA levels above the normal range (mean -9.4 +/- 4.9 nU/ml). At 6 wk of age, 37% of female NOD mice were CIAA+, whereas none of the male animals exceeded the normal range at this age (38 +/- 13 vs. 5 +/- 6 nU/ml, P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Genetically programmed selective islet beta-cell loss in diabetic subjects with Wolfram's syndrome.

Insulin-producing beta-cells were selectively absent from the islets of Langerhans in postmortem specimens from two patients with Wolfram's syndrome. In families with multiple cases of this syndrome, we found a very high concordance rate (r = .910, P less than .001) among siblings for age at onset of diabetes mellitus. Taken together with the lack of markers for an autoimmune process, these findings suggest that diabetes mellitus in this syndrome results from genetically programmed selective beta-cell death.

Transient hyperglycemia in childhood: identification of a subgroup with imminent diabetes mellitus.

Transient hyperglycemia may represent the earliest manifestation of IDDM. In a series of 30 children referred for transient hyperglycemia, 8/30 (27%) developed IDDM within 10 months of their initial evaluation. Three children with detectable cytoplasmic islet cell antibodies (ICA) and/or positive insulin autoantibodies (CIAA) all developed IDDM, compared to 21% of ICA negative children and 13% who were CIAA negative. Of those with impaired glucose tolerance, 6/11 (55%) developed IDDM, as did 1/14 with normal OGTT. Of the children with a low "K rate" on IVGTT, 75% developed IDDM, compared to 1/13 with a normal "K rate". All four children (100%) whose first phase (1' + 3') insulin secretion never exceeded the first percentile developed IDDM within nine months, while no child with first phase insulin secretion above the first percentile (0/16) developed IDDM during 19 +/- 9 months (mean +/- SD) of follow-up. Thus, in our experience the oral glucose tolerance test is a less accurate predictor of impending IDDM; immunological abnormalities have the highest positive predictive value, while the first phase insulin secretion during an intravenous glucose tolerance test has the highest negative predictive value and the greatest overall accuracy of prediction.