RESUMEN
OBJECTIVE: To analyze the relationship among metabolic control, IGF-I, and growth in pubertal diabetic subjects. RESEARCH DESIGN AND METHODS: In 72 diabetic children, we have studied the pattern of change of IGF-I, IGF-I SD score, IGF binding protein (BP)-1, and growth rate in different pubertal stages and have analyzed their relation to age sex, weight/length index, HbA1c, insulin concentration, insulin dose, and dehydroepiandrosteronesulfate (DHEAS). RESULTS: The serum IGF-I values increased up to Tanner stage 4 and thereafter decreased, whereas IGFBP-1 showed the inverse pattern. When transforming the IGF-I values into SD scores, correcting for age, sex, and pubertal stage, it was shown that the deviation from normal values increased with increasing pubertal stage in boys, but was equal in stages 3-5 in girls. Using multiple regression analysis, HbA1c, insulin dose, and DHEAS were significantly correlated to IGF-I SD score (R2 = 0.253, P = 0.001). IGFBP-I levels in the afternoon were within normal range. LogIGFBP-1 showed an inverse correlation, to insulin concentration in single correlation (r = -0.26, P = 0.02). In single correlation, growth rate correlated significantly to insulin dose (r = 0.25, P = 0.03). In a multiple regression analysis, only DHEAS and IGF-I SD score were found to be significantly correlated to growth rate (R2 = 0.370, P < 0.001). The 18 adolescents who had reached their final height did not deviate from their target final height, according to their recorded growth since birth. CONCLUSIONS: In a group of fairly well-controlled diabetic children, the normal increase in IGF-I during puberty is blunted. Despite decreased IGF-I levels, target final height was attained, probably because of adequate insulin compensation leading to normal IGFBP-l, thus adequate bioavailability of IGF-I. Our results point out the importance of sufficient exogenous insulin in the period of rapid linear growth.
Asunto(s)
Diabetes Mellitus/sangre , Crecimiento , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Pubertad/sangre , Adolescente , Adulto , Biomarcadores/sangre , Estatura , Índice de Masa Corporal , Niño , Sulfato de Deshidroepiandrosterona/sangre , Diabetes Mellitus/tratamiento farmacológico , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Masculino , Radioinmunoensayo , Caracteres Sexuales , SueciaRESUMEN
Hyperglycaemia and increased variability of blood glucose in pubertal children with type 1 diabetes may be related to increased growth hormone (GH) secretion and insulin resistance. The role of changes in insulin-like growth factor-I (IGF-I) bioavailability for the glycaemic control in these patients has not been completely elucidated. In particular, the possible role of increased IGF binding protein-3 (IGFBP-3) proteolysis reported in other insulin resistant states awaits further characterization. The aims of this study were to assess if hyperglycaemia in children with type 1 diabetes was associated with changes in free dissociable IGF-I (fdIGF-I) and IGF binding protein-3 protease activity (IGFBP-3-PA) and if increased insulin resistance during puberty was associated with changes in IGFBP-3-PA in healthy and diabetic children. In diabetic boys in the period of maximal linear growth (Tanner stage 3, n = 5), the mean level and the variability of IGFBP-3-PA, determined every second hour throughout 24 h, were significantly higher both compared to postpubertal diabetic boys (n = 6; P = 0.003 and P = 0.001, respectively), and to age matched healthy boys (n = 4; P = 0.006 and P < 0.001 respectively). This activation of IGFBP-3-PA was most prominent during the day time. The mean 24 h blood glucose level (determined hourly) was the only parameter studied that significantly predicted the changes in mean 24 h IGFBP-3-PA in the diabetes group. The mean 24 h concentrations of fdIGF-I were decreased in the diabetic boys compared to the healthy controls but statistical significance was only achieved in Tanner Stage 5 (p = 0.03). We speculate that the elevated levels of IGFBP-3-PA in Tanner 3 diabetic boys are related to deteriorated glucose homeostasis and that it may be a compensatory mechanism to attenuate the decrease in fdIGF-I in order to partly restore insulin sensitivity and glycemic control.
Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Adolescente , Adulto , Glucemia/metabolismo , Estudios de Casos y Controles , Niño , Humanos , Insulina/uso terapéutico , Resistencia a la Insulina , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Factores de TiempoRESUMEN
An ultrasonic system fitted with echo-tracking circuits was used to investigate the mechanical properties of the descending aorta in children and adolescents with insulin-dependent diabetes (IDDM). Seventy-six children and adolescents (aged 5-20 years) with uncomplicated diabetes and 75 age- and gender-matched healthy controls were examined. All subjects were normotensive. A nonlinear correlation between the stiffness index of the aorta and the age was found in both the diabetic (r = 0.47; P < 0.001) and control group (r = 0.57; P < 0.001). The stiffness index was higher among the diabetic subjects as compared to the controls (P < 0.01). No difference regarding stiffness of the aorta was found between genders in either of the groups. No correlation was observed between the stiffness index and the duration or degree of the metabolic control of diabetes. Our study demonstrated an increased stiffness of the aorta in children and adolescents with IDDM at the stage when no vascular complications were detected clinically.
Asunto(s)
Aorta Torácica/fisiopatología , Diabetes Mellitus Tipo 1/fisiopatología , Ultrasonografía/métodos , Adolescente , Adulto , Factores de Edad , Albuminuria/metabolismo , Aorta Torácica/diagnóstico por imagen , Índice de Masa Corporal , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Diabetes Mellitus Tipo 1/diagnóstico por imagen , Diabetes Mellitus Tipo 1/metabolismo , Elasticidad , Femenino , Hemoglobina Glucada/metabolismo , Hemodinámica , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Análisis de Regresión , Reproducibilidad de los Resultados , Factores SexualesRESUMEN
The aim of this study was to compare the frequency of human leukocyte antigen (HLA) genotypes in 1-18-year-old patients with type 1 diabetes newly diagnosed in 1986-1987 (n = 430), 1996-2000 (n = 342) and in 2003-2005 (n = 171). We tested the hypothesis that the HLA DQ genotype distribution changes over time. Swedish type 1 diabetes patients and controls were typed for HLA using polymerase chain reaction amplification and allele specific probes for DQ A1* and B1* alleles. The most common type 1 diabetes HLA DQA1*-B1*genotype 0501-0201/0301-0302 was 36% (153/430) in 1986-1987 and 37% (127/342) in 1996-2000, but decreased to 19% (33/171) in 2003-2005 (P \ 0.0001). The 0501-0201/0501-0201 genotype increased from 1% in 1986-1987 to 7% in 1996-2000 (P = 0.0047) and to 5% in 2003-2005 (P > 0.05). This study in 1-18-year-old Swedish type 1 diabetes patients supports the notion that there is a temporal change in HLA risk.
Asunto(s)
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Genotipo , Antígenos HLA/genética , Adolescente , Edad de Inicio , Niño , Preescolar , Diabetes Mellitus Tipo 1/epidemiología , Femenino , Frecuencia de los Genes , Antígenos HLA-DQ/genética , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Humanos , Lactante , Masculino , Suecia/epidemiologíaRESUMEN
SUMO4 M55V, located in IDDM5, has been a focus for debate because of its association to type I diabetes (TIDM) in Asians but not in Caucasians. The current study aims to test the significance of M55V association to TIDM in a large cohort of Swedish Caucasians, and to test whether M55V is associated in those carrying human leukocyte antigen (HLA) class II molecules. A total of 673 TIDM patients and 535 age- and sex-matched healthy controls were included in the study. PCR-RFLP was performed to identify the genotype and allele variations. Our data suggest that SUMO4 M55V is not associated with susceptibility to TIDM by itself. When we stratified our patients and controls based on heterozygosity for HLA-DR3/DR4 and SUMO4 genotypes, we found that presence of SUMO4 GG increased further the relative risk conferred by HLA-DR3/DR4 to TIDM, whereas SUMO4 AA decreased the risk. From the current study, we conclude that SUMO4 M55V is associated with TIDM in association with high-risk HLA-DR3 and DR4, but not by itself.
Asunto(s)
Diabetes Mellitus Tipo 1/genética , Antígeno HLA-DR3/genética , Antígeno HLA-DR4/genética , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/genética , Adolescente , Adulto , Alelos , Estudios de Casos y Controles , Niño , Preescolar , Estudios de Cohortes , Diabetes Mellitus Tipo 1/inmunología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Antígeno HLA-DR3/inmunología , Antígeno HLA-DR4/inmunología , Haplotipos , Humanos , Lactante , Recién Nacido , Masculino , Polimorfismo de Nucleótido Simple , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/inmunología , SueciaRESUMEN
In a large case-control study of Swedish incident type I diabetes patients and controls, 0-34 years of age, we tested the hypothesis that the GIMAP5 gene, a key genetic factor for lymphopenia in spontaneous BioBreeding rat diabetes, is associated with type I diabetes; with islet autoantibodies in incident type I diabetes patients or with age at clinical onset in incident type I diabetes patients. Initial scans of allelic association were followed by more detailed logistic regression modeling that adjusted for known type I diabetes risk factors and potential confounding variables. The single nucleotide polymorphism (SNP) rs6598, located in a polyadenylation signal of GIMAP5, was associated with the presence of significant levels of IA-2 autoantibodies in the type I diabetes patients. Patients with the minor allele A of rs6598 had an increased prevalence of IA-2 autoantibody levels compared to patients without the minor allele (OR=2.2; Bonferroni-corrected P=0.003), after adjusting for age at clinical onset (P=8.0 x 10(-13)) and the numbers of HLA-DQ A1*0501-B1*0201 haplotypes (P=2.4 x 10(-5)) and DQ A1*0301-B1*0302 haplotypes (P=0.002). GIMAP5 polymorphism was not associated with type I diabetes or with GAD65 or insulin autoantibodies, ICA, or age at clinical onset in patients. These data suggest that the GIMAP5 gene is associated with islet autoimmunity in type I diabetes and add to recent findings implicating the same SNP in another autoimmune disease.
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Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Proteínas de Unión al GTP/genética , Adolescente , Adulto , Autoanticuerpos/sangre , Estudios de Casos y Controles , Niño , Preescolar , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Proteínas de Unión al GTP/metabolismo , Humanos , Lactante , Recién Nacido , Masculino , Polimorfismo de Nucleótido Simple , SueciaRESUMEN
The 24 h urinary C-peptide excretion was determined in 137 normal healthy children, 52 girls and 85 boys, 3-15 years of age. No significant difference was found between boys and girls. Median value of urinary C-peptide for boys and girls was 0.24 nmol/kg/24 h with a range of 0.07-0.61 nmol/kg/24 h. Urinary C-peptide correlated positively and significantly with age, weight, height, body surface area and the 24 h urinary creatinine excretion. Since the values of C-peptide excretion were not normally distributed they were log transformed and plotted against body weight. The linear regression and the 95% confidence limits were then calculated. Girls at puberty, 11-15 years of age, had significantly higher C-peptide excretion per kg body weight and per body surface area than younger girls, 3-10 years of age. Boys 13-15 years of age had significantly higher C-peptide excretion per body surface area than younger boys, 5-12 years of age. This indicates that children during the maximal growth spurt have an increased insulin secretion as measured by urinary C-peptide per body surface area.
Asunto(s)
Péptido C/orina , Adolescente , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Masculino , Valores de Referencia , Factores SexualesRESUMEN
Metabolic control and blood glucose variability in children with insulin-dependent diabetes mellitus (IDDM) during and after puberty were studied. Seventy-two children (43M, 29F), aged 10-19 years, with a 2-16-year duration of IDDM participated in the study. Fourteen of the patients were prepubertal (Tanner stage 1), 27 pubertal (Tanner 2-4) and 31 postpubertal (Tanner 5). They performed self-monitoring of blood glucose (SMBG) five times daily, every 2 days for 4 weeks. The SD (SDbg) for all values in each patient was calculated as a measure of blood glucose variability. Weight-length index, linear growth velocity and Tanner stage were recorded. Hemoglobin (Hb)A1c, alkaline phosphatase and sex hormone levels in serum were analyzed. Subjectively experienced hypoglycemic episodes were recorded. HbA1c levels showed no relation to Tanner stage. SDbg was lower in stage 5 than in stages 2-4 (p = 0.02). There was no significant correlation between HbA1c and SDbg, but the variability was significantly lower in individuals with mean blood glucose in the lower quartile compared with those in the upper three quartiles (p < 0.001). Alkaline phosphatase concentration, as a measure of growth velocity, was the main independent determinant of SDbg (r = 0.35, p < 0.005). There was an inverse correlation between levels of sex hormones and SDbg. We conclude that blood glucose variability is lower after than during puberty. This variability seems to be related to linear growth velocity or its biochemical marker.
Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Adolescente , Adulto , Fosfatasa Alcalina , Peso Corporal , Niño , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/fisiopatología , Femenino , Hemoglobina Glucada/metabolismo , Hormonas Esteroides Gonadales/sangre , Crecimiento , Humanos , Insulina/administración & dosificación , Masculino , Pubertad , Análisis de Regresión , Factores SexualesRESUMEN
To assess the total insulin secretion in children in different nutritional states we have analysed the 24 h urinary C-peptide excretion in 32 obese children (16 boys and 16 girls) 8-15 years of age as well as in 7 girls with anorexia nervosa 11-16 years of age. Obese children had a median urinary C-peptide excretion rate of 0.27 nmol/kg/24 h, which was not different from that of a group of normal-weight children. In the group of anorectic girls, on the other hand, the median value 0.47 nmol/kg/24 h was significantly (p less than 0.05) higher than for normal-weight girls of the same age (median = 0.26 nmol/kg/24 h). These results indicate that in obese children insulin secretion, measured as the 24 h urinary C-peptide excretion per kg body weight, is the same as in normal-weight children. Total insulin secretion is consequently increased. In anorexia nervosa, on the other hand, the higher C-peptide excretion per kg body weight compared with normal-weight children, indicates that insulin secretion is increased in relation to body weight.
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Anorexia Nerviosa/fisiopatología , Péptido C/orina , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Obesidad/fisiopatología , Adolescente , Anorexia Nerviosa/orina , Peso Corporal/fisiología , Niño , Ritmo Circadiano/fisiología , Femenino , Humanos , Secreción de Insulina , Masculino , Obesidad/orinaRESUMEN
UNLABELLED: The aim of the present study was to investigate whether the diurnal variability of B-Glucose is dependent on GH, IGF-I and IGFBP-1 levels, apart from insulin, and if there is any difference between Tanner stages 3 and 5. Five boys in Tanner stage 3 and 6 boys in stage 5 with type 1 diabetes were included. Blood was continuously collected from a cubital vein for 24 h. S-Insulin, S-GH, S-IGF-I and S-IGFBP-1 were analysed. B-Glucose was analysed hourly at bedside. One week before and 1 wk after the 24-h study period the participants performed self-monitoring of blood glucose (SMBG) during normal physiologic conditions. In the 24-h profile of B-Glucose, insulin, IGFBP-1 and GH, we found a significant positive correlation between B-Glucose and log IGFBP-1 (r = 0.5, p = 0.005) and an inverse correlation to insulin (r = -0.5, p = 0.004) but no correlation to logGH (r = -0.04, p = 0.831). In multiple regression analysis, B-Glucose was still significantly correlated to log IGFBP-1, when adjusting for insulin and GH, in Tanner stage 5. We found a difference between Tanner stages 3 and 5 in the variability of B-Glucose over a longer period during normal daily activity (p = 0.02), but not over the 24-h study period. CONCLUSION: We have demonstrated in type 1 diabetes adolescent boys a relationship between simultaneously measured blood-glucose and IGFBP-1 levels independent of the insulin and GH levels, suggesting that the free fraction of IGF-I influences the glucose metabolism.
Asunto(s)
Diabetes Mellitus Tipo 1/metabolismo , Glucosa/metabolismo , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/fisiología , Adolescente , Niño , Ritmo Circadiano , Humanos , MasculinoRESUMEN
The response of C-peptide in serum and urine and of glucose and branched chain amino acids in blood to formula and breast feeding was assessed in six breast-fed and six formula-fed infants 3-6 months of age. We analysed serum C-peptide, branched chain amino acids (BCAA) in blood, and blood glucose in the fasting state at 90' and 180' after a regular meal. The excretion of urinary C-peptide and creatinine was also determined. The formula-fed infants received a formula in current use, containing 15-16 g protein/l and with a casein/whey ratio of 40/60. In the fasting state, no significant inter-group difference was found in the level of serum C-peptide or the valine/glycine ratio. Postprandially, the formula-fed infants had significantly higher serum C-peptide values and valine/glycine ratio than the breast-fed infants, p less than 0.05. No significant inter-group difference was found for blood glucose. The urinary C-peptide/creatinine ratio was significantly lower in the breast-fed group, p = 0.02, and significantly correlated both to the valine/glycine ratio at 90', rs = 0.75, p = 0.02 and to the serum C-peptide value at 90', rs = 0.66, p = 0.03. These results confirm that in formula-fed infants the insulin response to a meal is enhanced compared to that in breast-fed infants. The finding of similar blood glucose values in the two groups may also indicate an insulin resistance in the formula-fed infants following a meal.
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Aminoácidos de Cadena Ramificada/sangre , Glucemia/análisis , Péptido C/sangre , Alimentos Infantiles , Leche Humana/metabolismo , Lactancia Materna , Péptido C/orina , Creatinina/orina , Femenino , Glicina/sangre , Humanos , Lactante , Insulina/metabolismo , Secreción de Insulina , Isoleucina/sangre , Leucina/sangre , Masculino , Valina/sangreRESUMEN
To evaluate vascular function in diabetic subjects, we studied both the stiffness of the abdominal aorta and the foot microvascular reactivity in 22 diabetic adolescents and 18 controls. The aortic stiffness was significantly higher in diabetic females, but not in males, as compared to age- and gender-matched controls (p < 0.05). Foot post-ischaemic hyperaemia was lower in diabetic subjects than in controls (p < 0.05), while postural vasoconstriction did not differ between the groups. The microvascular reactivity did not correlate with the duration of diabetes, but seemed to be influenced by the insulin regimen. The degree of aortic stiffness and the microvascular reactivity of the foot were not significantly interrelated. Loss of aortic elasticity might be a long-term effect of diabetes, whereas microvascular reactivity seems to reflect the current influence of the metabolic state and insulin treatment.
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Aorta Torácica/diagnóstico por imagen , Diabetes Mellitus Tipo 1 , Pie/irrigación sanguínea , Microcirculación , Adolescente , Adulto , Aorta Torácica/fisiología , Índice de Masa Corporal , Femenino , Pie/diagnóstico por imagen , Humanos , Flujometría por Láser-Doppler , Masculino , UltrasonografíaRESUMEN
OBJECTIVE: Gestational diabetes is associated with increased risk of developing noninsulin-dependent diabetes (NIDDM) later in life. By the time that a diagnosis of NIDDM is established, functional disturbances in the vascular system may be observed. This study was planned to assess macro- and microvascular function in nonpregnant women without signs of diabetes two to four years after a pregnancy complicated with gestational diabetes. DESIGN: Cross-sectional study. SETTING: Vascular research laboratory in the obstetric unit of a university hospital. PARTICIPANTS: Seventeen nonpregnant, healthy women with a history of gestational diabetes and 20 nonpregnant control women of similar age without previous diabetes. METHODS: For quantification of the mechanical properties in large arterial vessels the wall movements of the abdominal aorta and left common carotid artery were recorded with an ultrasonic tracking system. Microvascular perfusion in the skin of the hand and foot was recorded by a laser Doppler technique to assess the vasodilatory response induced by transcutaneous acetylcholine. RESULTS: Women in the gestational diabetes group showed evidence of increased wall stiffness in the common carotid artery and a lower maximum incremental velocity of the pulsatile vessel diameter change in both aorta and carotid artery compared with controls. Acetylcholine induced vasodilatation in both hand and foot was lower in women with previous gestational diabetes compared with controls. CONCLUSION: Abnormal vascular function was found in asymptomatic women with a history of gestational diabetes. It is speculated that these abnormalities might be early evidence of vascular complications associated with subsequent NIDDM.
Asunto(s)
Acetilcolina/farmacología , Aorta Abdominal/fisiología , Arteria Carótida Común/fisiología , Diabetes Gestacional/fisiopatología , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología , Adulto , Estudios Transversales , Elasticidad , Femenino , Humanos , Microcirculación/efectos de los fármacos , Embarazo , Flujo Pulsátil , Piel/irrigación sanguíneaRESUMEN
Using the country-wide Swedish childhood diabetes register 526 children, who had had diabetes for 6-30 months were traced for measurements of 24-hour urinary C-peptide. Lost beta-cell function was defined as a 24-hour urinary C-peptide excretion per kg body weight less than 10% of the mean for healthy children (less than 0.025 nmol/kg). The estimated cumulative incidence of lost beta-cell function was 0.64 at 30 months. The incidence of lost beta-cell function did not differ by sex. Neither was there any significant variation in season at onset for cases with lost beta-cell function. A significant age dependency was shown for the cumulative incidence of lost beta-cell function with the highest incidence in the young age groups, i.e. a reversed age dependency compared to that of clinical onset. In contrast to the clinical onset of diabetes no significant geographical variation was found for lost beta-cell function when comparing standardized morbidity ratios. The urinary C-peptide excretion was significantly correlated to age at onset but not to degree or duration of ketonuria at onset. It is concluded that there are striking differences when comparing the epidemiology of lost beta-cell function to that of clinical onset in terms of age, sex, seasonal and geographical variations. The timing of clinical onset may thus partly be determined by factors different from those determining the rate of fall in beta-cell function.
Asunto(s)
Diabetes Mellitus Tipo 1/epidemiología , Islotes Pancreáticos/fisiopatología , Adolescente , Factores de Edad , Péptido C/orina , Niño , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Hemoglobina Glucada/análisis , Humanos , Insulina/administración & dosificación , Masculino , Estaciones del Año , Factores Sexuales , SueciaRESUMEN
The pattern of fall in B-cell function measured as plasma and 24 h urinary C-peptide excretion, as well as levels of islet cell antibodies, insulin antibodies and metabolic parameters, were followed for two years in 39 children aged 1-17 years prospectively from clinical onset of Type 1 (insulin-dependent) diabetes. At onset 32/36 patients had measurable plasma C-peptide (median 0.13 nmol/l). Maximum values of fasting and postprandial plasma C-peptide were reached at a median duration of three months. Thereafter both plasma and urinary C-peptide declined linearly. The median value of the rate of fall in postprandial plasma C-peptide was 0.019 nmol.1-1.month-1. Age at onset was positively correlated to the maximum value of postprandial plasma C-peptide in each patient (rs = 0.57, p = 0.0001) and throughout the observation time positively correlated to fasting and postprandial C-peptide and to the 24 h urinary C-peptide excretion (rs range 0.35-0.70, p = 0.03-0.0001). The rate of fall of postprandial C-peptide was unrelated to age at onset and was strikingly parallel in different age groups. Islet cell antibodies were present in 87% of the patients at onset and decreased to 38% at 24 months. Islet cell antibody titres were not correlated to age at onset or to plasma or urinary C-peptide at any single observation. However, islet cell antibody negative patients had significantly higher (p less than 0.05) postprandial plasma C-peptide values at 1, 9, and 12 months of duration, compared to islet cell antibody positive patients.(ABSTRACT TRUNCATED AT 250 WORDS)