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Results for “Glycemic variability”

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At least 523 records · Page 29Linked to original sources

PubMed1998

The glucose/insulin system and vitamin C: implications in insulin-dependent diabetes mellitus.

The cellular uptake of vitamin C (ascorbic acid, ASC) is promoted by insulin and inhibited by hyperglycemia. If a rise in plasma ASC is uncoupled from insulin replacement in insulin-dependent diabetes mellitus (IDDM) then the degree of hyperglycemia could account for "tissue scurvy" in IDDM. Leukocyte ASC is lower in IDDMs compared with nondiabetics when vitamin C consumption is adequate and our data suggest that this is a variable component of the pathophysiology of IDDM. The complications of diabetes mellitus are believed to result from either the intracellular accumulation of sorbitol or the nonenzymatic glycoxidation of proteins or both. With respect to the abnormal cellular accumulation of sorbitol, vitamin C supplementation has been shown to be effective in several studies of adults with diabetes; the situation regarding the prevention of protein glycoxidations by supplementation is presently unclear. The roles of ASC as an aldose reductase inhibitor and a water soluble antioxidant in body fluids are potentially very important as adjuncts to tight glycemic control in the management of diabetes. Tissue saturation and maximal physiologic function in IDDM may require supplemental vitamin C intake.

Adult↗

PubMed2003

Young and elderly type 2 diabetic patients inhaling insulin with the AERx insulin diabetes management system: a pharmacokinetic and pharmacodynamic comparison.

The objective of this study was to compare the pharmacokinetics (PK), pharmacodynamics (PD), and safety of inhaled insulin delivered by the AERx iDMS in young and elderly patients with type 2 diabetes. Twenty-seven young (18-45 years, inclusive) and 28 elderly (>/= 65 years) type 2 diabetic patients were enrolled in this study. A single inhalation of 1.57 mg (45 IU, effect comparable to 6 s.c. units) of regular human insulin was administered to each patient on each of 2 dosing days, and blood samples were drawn up to 360 minutes postdosing to generate the PK/PD curves. AUC(0-360 min) and Cmax values of inhaled insulin were comparable between young and elderly subjects (p = 0.476 for AUC(0-360 min) and p = 0.414 for Cmax). However, the elderly group had significantly less glucose reduction, as indicated by plasma glucose AOC(0-360) (area over the curve) values (p = 0.011). The intrasubject variability of inhaled insulin using the AERx iDMS was similar for young and elderly subjects and was similar to what has previously been reported for soluble insulin administered subcutaneously. Inhaled insulin was well tolerated in these patients, and no changes in pulmonary function tests were observed. A single inhalation of insulin using the AERx iDMS demonstrated comparable insulin PK profiles between the elderly and young type 2 patients but less glucose reduction in the elderly. Based on these results, elderly diabetic patients may need to inhale more insulin than young patients to achieve similar glycemic control. Long-term clinical trials using the AERx device will be useful to study age-related differences.

Administration, Inhalation↗

PubMedDate not supplied

[Diabetes mellitus: causes for hospitalization, intrahospital complications and mortality].

OBJECTIVE: To determine hospitalization causes, complications and mortality in Mexican patients with diabetes mellitus (DM). METHODS: Between July and December 2001, we reviewed all admissions to the Department of Internal Medicine. Patients with a diagnosis of DM were included. A structured questionnaire was applied with the assessment of the following variables: sociodemographic; clinical history; variables associated with DM (complications associated with DM, treatment and diet, control of the disease by general practitioner or specialist); admissions (causes, length of stay, complications, glycemia at onset of admission and causes of death). RESULTS: One hundred forty-seven patients were hospitalized, 57% were women with a mean age of 58 years and disease duration of 165 months; 43% knew their glycemia value upon admission and 67% were seen in the outpatient clinic 30 days previous to admission. At onset of hospitalization 61% were hyperglycemic, 5% had hypoglycemia and 22% had normal glycemic values. The causes of hospitalization were cardiovascular diseases (37%), complications associated with DM (20%), and infections (18%). The mean length of hospital stay was 10 days. There were 16 (11%) deaths specifically due to cardiovascular disease. CONCLUSIONS: Frequent causes of hospitalizations, intrahospital complications and deaths were similar to previous studies in other countries.

Diabetes Complications↗

PubMed1990

Early neonatal predictors of neonatal hypocalcemia in infants of diabetic mothers: an epidemiologic study.

Prematurity, neonatal asphyxia, hypomagnesemia, and advanced maternal diabetes are traditional risk factors for hypocalcemia in infants of diabetic mothers (IDMs). The aim of this study was to determine the relative contribution of these factors separately and combined in a cohort of diabetic pregnancies managed prospectively in the recent 9 years and to find accurate predictors of neonatal hypocalcemia in infants of diabetic mothers. We hypothesized that these factors plus low cord blood calcium (Ca) concentration allow prediction of IDMs who develop neonatal hypocalcemia. We studied 186 IDMs (White class B-RT); gestational age (GA, weeks) was by last menstrual period, confirmed +/- 2 weeks by Ballard score. The goals of glycemic control were: preprandial blood glucose less than 100 mg/dl and 90-minute postprandial blood glucose less than 140 mg/dl. Apgar scores, and cord, 24-, 48- and 72-hour serum calcium (Ca) (mg/dl) and magnesium (Mg; mg/dl) were determined. In univariate analysis, lowest serum Ca correlated with cord blood Ca (r = 0.48, p less than 0.001), GA (r = 0.37, p less than 0.001), and 1-minute Apgar score (r = 0.18, p = 0.09), but did not correlate with cord Mg or with advanced White class. In multiple regression, cord Ca and GA were dominant effects and other variables became insignificant. Lowest Ca (mg/dl) was predicted as follows: lowest Ca = 34.05 - 3.22 (Ca cord) - 0.84 (GA) + 0.10 (GA) (Ca cord). This equation predicts neonatal hypocalcemia (lowest Ca less than 8 mg/dl) with a sensitivity of 72% and a specificity of 75%. Thus, GA and cord Ca allow determination of IDMs at risk for neonatal hypocalcemia.

Asphyxia Neonatorum↗

PubMed1990

Relationship between dietary fiber content and composition in foods and the glycemic index.

The dietary fiber content and composition of 25 foods were related to their glycemic index (GI) to see whether the individual components of dietary fiber, specifically soluble fiber, would provide a better predictive capability of the glycemic response than their total dietary fiber content. Total dietary fiber was significantly related to GI (r = 0.461, p less than 0.05). Soluble fiber was not significantly related to GI (r = 0.308), and uronic acids in insoluble fiber were most closely related to GI (r = 0.584, p less than 0.01). Multiple-regression analysis showed that more variation of GI was explained by uronic acids in insoluble fiber (34%) than by total dietary fiber alone (21%, p = 0.05). The combination of pentoses, hexoses, and uronic acids in soluble and insoluble fiber explained only 50% of GI variability. In determining the potential metabolic effects of diet, physiologic assessment of foods is a useful supplement to chemical analysis of their dietary fiber content and composition.

Biological Availability↗

PubMedDate not supplied

Efficacy and safety of a purified porcine insulin zinc suspension for managing diabetes mellitus in dogs.

The objective of this study was to evaluate the safety and efficacy of a purified porcine insulin zinc suspension for treating dogs with uncomplicated diabetes mellitus. Fifty-three dogs were treated for 60 days after an initial dose determination period. The means of the blood glucose concentrations during 12-hour glucose curves and the means of the blood glucose nadir concentrations during 12-hour glucose curves for all dogs were determined before beginning insulin therapy (time 0), at the end of the dose determination period (time 1), 30 days after time 1 (time 2), and 60 days after time 1 (time 3). Presence of polyuria, polydipsia, and ketonuria was determined at each time point. Adequacy of control of hyperglycemia was based on 12-hour blood glucose curves and improvement in clinical variables (results of physical examinations, historic information, polyuria, polydipsia, and ketonuria). Safety was evaluated by questionnaire, performance of physical examination, CBC, serum chemistry profile, and urinalysis. The means of the blood glucose concentrations during 12-hour glucose curves and the means of the blood glucose nadir concentrations during 12-hour glucose curves for all dogs at times 1, 2, and 3 were significantly lower compared with time 0 (P < .0001). There was a reduction in the proportion of dogs with polyuria, polydipsia, and ketonuria of 82, 86, and 80%, respectively. All of the dogs had adequate glycemic control at time 1, 66% at time 2, and 75% at time 3. At time 3, 66% of dogs required insulin injections q12h. Other than hypoglycemia, there were no important adverse effects of insulin administration. The insulin, was safe and efficacious for reducing blood glucose and clinical signs in dogs with diabetes mellitus.

Animals↗

PubMed1993

Improvement of diabetic control and acceptability of a three-injection insulin regimen in diabetic adolescents. A multicenter controlled study.

OBJECTIVE: To compare the effectiveness and acceptability of a three-injection insulin regimen with the conventional two-injection therapy in an unselected population of diabetic adolescents. RESEARCH DESIGN AND METHODS: Some 205 patients aged 10-18 yr with IDDM, who were previously treated with two daily insulin injections, were included without any selection into a randomized trial. They were either switched to three (regular prebreakfast, regular prelunch, and [regular+ultralente] predinner) or remained on two ([regular+intermediary] prebreakfast and predinner) subcutaneous injections. They were evaluated after 1 yr of treatment. The major criteria of outcome of efficacy were the concentration of GHb, the frequency of severe hypoglycemia and DKA, and body weight. RESULTS: Of the patients, 82% accepted the three-injection regimen, and 83% accepted the two-injection regimen. At entry into the trial, no significant differences appeared between the two treatment groups nor among patients refusing the allocated regimen. Significant explanatory variables predicting initial diabetes control were duration of disease and adherence to diet. GHb, decreased from 9.8 +/- 0.1 to 9.3 +/- 0.2% (P < 0.05) in the three-injection group, whereas it increased from 9.5 +/- 0.3 to 9.8 +/- 0.3% (P < 0.05) in the two-injection group, resulting in a modest (0.75%) but significant difference (P < 0.05) between GHb change in the two groups. The difference reached 1.4% (P < 0.0002) in patients with GHb > 11.2% at entry. The frequency of hypoglycemia and DKA was similar in the two groups. None of the parameters known to potentially influence glycemic control changed during the trial, and, therefore, the improvement of GHb could be attributed to the pattern of daily insulin distribution per se. CONCLUSIONS: In the general diabetic adolescent population, the efficacy of a three-injection regimen is somewhat superior to that of a conventional two-injection regimen, particularly in patients previously poorly controlled. The acceptability of this regimen being excellent, its increased use should be considered in this age-group.

Adolescent↗

PubMed1999

Inhaled insulin.

Inhalation of regular insulin for meal time glucose control has been found to be safe, efficacious and reliable in Type I and Type II diabetics. The administration of regular insulin through the human lungs by inhalation has been conducted in at least 14 short studies in both normal and diabetic subjects beginning as early as 1925. In all studies, significant insulin absorption and lowering of blood glucose was observed in the absence of penetration enhancers. Although a concern of variable dosing was raised in early studies, the development of new reproducible delivery systems has ensured that the variability of aerosol insulin can be as good, if not better, than subcutaneous (SC) injection. In the longest controlled studies in humans to date, both Type I and Type II insulin-dependent diabetics used a novel inhaled dry powder insulin delivery system for 3 months for meal time glucose control. The study results indicate that inhaled insulin provides equivalent glucose control, measured by hemoglobin A1c, when directly compared to SC injection. Interim results from an additional study with Type II diabetics who were failing oral hypoglycemic agents suggest that adjunctive therapy with inhaled insulin markedly improved glycemic control with a low risk of hypoglycemia. In all the 3 month studies the system was efficacious, well tolerated, well liked, and resulted in reproducible results. A potential advantage of aerosol insulin is that it is more rapidly absorbed (serum peak at 5-60 min) and cleared than SC injection (peak at 60-150 min), which provides a more relevant and convenient therapy for meal time glucose control. The relative efficiency of insulin delivery by aerosol, compared to SC injection, has been estimated from the dose measured at the exit point of the aerosol device, and found to range between 8 and 25% of SC, depending on the study.

Journal Article↗

PubMed2004

Peripheral vascular disease is associated with reduced glycosuria in newly diagnosed type 2 diabetic patients.

OBJECTIVES: We examined whether the finding of glycosuria and its level in themselves give information of clinical relevance, apart from being an unreliable indicator of glycemic control. METHODS: Subjects were a population-based sample of 1,284 newly diagnosed type 2 diabetic patients. Median age was 65.2 years. Urinary glucose concentration (UGC) was determined quantitatively in a freshly voided morning urine specimen. RESULTS: The over-all prevalence of peripheral vascular disease (PVD) was 16.5%. Bivariately, high values of UGC were associated with low prevalence of PVD (p<0.001, chi2-test). The predictive value of PVD--together with HbA1c, glomerular filtration rate (GFR) and 10 other possible predictors--was confirmed in a logistic regression analysis with glycosuria (Y/N) as outcome variable (p=0.0004). CONCLUSION: Surprisingly, type 2 diabetic patients with PVD tend not to have glycosuria as compared to patients without PVD. PVD may be indicative of generalized atherosclerotic lesions in the major vessels, including the renal arteries. This could lead to a lowering of GFR and thereby of the amount of glucose filtered. Assuming no, or only a minor direct effect of PVD on tubular function, this would lead to an increased renal threshold for glucose in patients with PVD.

Aged↗

PubMed1997

Nighttime insulin kinetics and glycemic control in type 1 diabetes patients following administration of an intermediate-acting lispro preparation.

OBJECTIVE: To determine insulin kinetics and overnight glycemic control after bedtime administration of a new intermediate-acting insulin preparation called neutral protamine lispro (NPL). RESEARCH DESIGN AND METHODS: We studied 12 patients with well-controlled type 1 diabetes. The study had a double-blind, randomized, crossover design. After a lead-in period of 10-14 days two experiments were carried out with an interval of 2-7 days. During these experiments overnight insulin kinetics and fasting blood glucose levels were studied after evening administration of NPH insulin and NPL. Blood glucose levels < 3.8 mmol/l were treated by means of a variable infusion of a 20% glucose solution. RESULTS: A trend toward a shorter time to peak insulin concentration was observed after administration of NPL (P = 0.07). No differences between NPH and NPL were detected in the total area under the curve (AUC) for insulin, in insulin levels before breakfast, or in glucose levels before breakfast (P = 0.5, 0.6, and 0.4, respectively). CONCLUSIONS: We detected no major differences between NPH and NPL in the total AUC for insulin, prebreakfast glucose levels, or prebreakfast insulin levels. Therefore, we conclude that NPH and NPL are equally effective in controlling overnight glycemia.

Adult↗

PubMedDate not supplied

Glycemic control and bone age are independently associated with muscle capillary basement membrane width in diabetic children after puberty.

This study was undertaken to examine the possible relationships between muscle capillary basement membrane width (CBMW) and glycemic control, bone age, chronologic age, and duration of diabetes in young patients with insulin-dependent diabetes mellitus (IDDM) during different stages of pubertal development. We studied 49 males and 43 females (age, 7-20 yr) with IDDM for up to 16 yr for whom bone age and glycosylated hemoglobin (HbA1c) data were available at the time of right quadriceps muscle biopsy. Based on pubic hair Tanner stage, subjects were assigned to prepubertal (Tanner I), pubertal (Tanner II and III), and postpubertal (Tanner IV and V) groups. In 30 pubertal and prepubertal subjects, none of the variables studied was significantly correlated with CBMW. This is attributable in part to the small number of subjects in each group. In 62 postpubertal subjects, CBMW was correlated with age (r = .27, P = .03), bone age (r = .43, P = .0005), and postpubertal duration of diabetes (r = .38, P = .003) but not total duration of diabetes. In the postpubertal subjects, CBMW was correlated with HbA1c at the time of biopsy (r = .31, P = .01) but correlated more strongly with the mean of HbA1c values obtained during the 1- and 2-yr periods before biopsy (r = .37, P = .01, and r = .54, P = .03, respectively). An analysis of covariance revealed that the slopes for the regression of loge CBMW on HbA1c differed significantly (P = .02) among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1987

Rapid decrease of insulin-specific IgG antibody levels in insulin-dependent patients transferred to semi-synthetic human insulin.

A multicenter, open trial was designed to examine the efficacy and safety of semi-synthetic human insulin (SSHI; Novolin R and Novolin L, SQUIBB-NOVO) in patients with insulin-dependent diabetes mellitus who were transferred from other commercially-available insulins. Whether such a change in therapy would reduce circulating IgG antibodies to antibovine insulin was also evaluated. A total of 68 males and females, 8-62 yr of age, were maintained on their original insulin therapy for 4 weeks, when both glycosylated hemoglobin and fasting blood glucose were assessed. IgG antibody titers to antibovine insulin were also measured. All patients were then transferred to SSHI for a period of 20 weeks. The same variables were evaluated at Weeks 2, 4, 8, and 20. Mean fasting blood glucose levels rose monotonically from 189-226.3 mg/dl over the course of the 20-week clinical trial. There was a slight but insignificant increase in glycosylated hemoglobin by the end of the test period. The average value for antibovine insulin IgG antibodies decreased from 2.54 mu/ml at baseline to 1.32 mu/ml by the completion of the trial. Significant decreases were first observed 4 weeks after the patients were placed on SSHI therapy. After transfer to SSHI, 43.3% of the patients achieved some improvement in glycemic control and only 16.4% were worse than at baseline. A decrease in weekly hypoglycemic reactions occurred during the course of the SSHI therapy. It appears that SSHI provides safe and effective treatment for insulin-dependent diabetic patients and that its use results in a rapid and significant decrease in insulin antibody formation.

Adult↗

PubMed2002

Prevalence of anxiety in adults with diabetes: a systematic review.

BACKGROUND: Anxiety is associated with decreased functioning and quality of life. It may have added importance in diabetes for its potential adverse effects on regimen adherence and glycemic control. OBJECTIVE: To estimate the prevalence of clinically significant anxiety in adults with diabetes. RESEARCH DESIGN AND METHODS: MEDLINE and PsycINFO databases and published reference lists were searched to identify studies that determined the prevalence of anxiety in diabetes from threshold scores on self-report measures or from diagnostic interviews. Prevalence was calculated as an aggregate mean weighted by the combined number of subjects in the included studies. RESULTS: Eighteen studies having a combined population (N) of 4076 (2584 diabetic subjects, 1492 controls) satisfied the inclusion criteria. Most did not adjust for the effects of moderator variables such as gender, and only one was community-based. Generalized anxiety disorder (GAD) was present in 14% of patients with diabetes. The subsyndromal presentation of anxiety disorder not otherwise specified and of elevated anxiety symptoms were found in 27% and 40%, respectively, of patients with diabetes. The prevalence of elevated symptoms was significantly higher in women compared to men (55.3% vs. 32.9%, P<.0001) and similar in patients with Type 1 vs. Type 2 diabetes (41.3% vs. 42.2%, P=.80). CONCLUSION: GAD is present in 14% and elevated symptoms of anxiety in 40% of patients with diabetes who participate in clinical studies. Additional epidemiological studies are needed to determine the prevalence of anxiety in the broader population of persons with diabetes.

Adult↗

PubMed1998

Gastric emptying delay and gastric electrical derangement in IDDM.

OBJECTIVE: Patients with diabetes can develop gastrointestinal motor complications; however, prevalence of gut dysmotility in children with diabetes is poorly understood. We measured gastric emptying time and gastric electrical activity in children with IDDM; presence of dyspeptic symptoms was also assessed. RESEARCH DESIGN AND METHODS: Gastric emptying time and gastric electrical activity were measured by ultrasonography and electrogastrography (EGG), respectively, in 40 consecutive IDDM children (median age: 9 years [6-14]) without autonomic neuropathy; 15 healthy children (median age: 7 years [4-15]) served as control subjects. The EGG variables studied were percent of electrical dysrhythmias (bradygastria or 0.5-2.0 cpm, tachygastria or 4.0-9.0 cpm; normal rhythm is 2.0-4.0 cpm) and fed-to-fasting ratio of the dominant EGG power. Blood glucose level in the fasting state and 180 min after feeding and HbA1C concentration were also measured. Data are given as median (ranges) and means +/- SD. Statistical analysis was performed using the parametric t test and the nonparametric signed-rank tests, with P < 0.05 considered significant. RESULTS: Gastric emptying time was delayed in 26 patients (group A), whereas in 14 patients (group B), it was in the same range as control values; group A patients significantly differed from group B for increased prevalence of gastric electrical dysrhythmias (P < 0.01) and for a lower fed-to-fasting ratio of the dominant EGG power (P < 0.01). Group B patients did not differ from control subjects for the EGG variables measured. Diabetic children with gastroparesis had significantly higher levels of both HbA1C and blood glucose measured 180 min after feeding than those with normal gastric emptying time (P < 0.05); there was a significant correlation between levels of HbA1C and degree of gastric emptying delay, whereas a significant inverse correlation between gastric emptying time and fed-to-fasting ratio of the dominant EGG power was found both in patients and control subjects. CONCLUSIONS: Delay of gastric emptying time and gastric electrical abnormalities are found in a high proportion of children with diabetes and can contribute to poor glycemic control, most likely by causing a mismatch between the onset of insulin action and the delivery of nutrients into the small intestine. Diabetic children with unexplained poor glycemic control should be investigated for abnormalities in gastric motility.

Adolescent↗

PubMed2000

Nationwide program for improving the care of diabetic patients in Israeli primary care centers.

OBJECTIVE: To improve the effectiveness of primary care providers in Israel to monitor and control glycemic levels of diabetic patients. RESEARCH DESIGN AND METHODS: We designed a 2-year program to improve the effectiveness of primary care providers to administer diabetes care. The program was conducted by the largest Israeli health maintenance organization, which insures 60% of the population. Interventions included continuing medical education and establishing guidelines and diabetes registers in every clinic. A retrospective cohort study was conducted from 1995 to 1997 to evaluate the project's effect on the care of diabetic patients. One patient was randomly chosen for review from each of the physicians' updated diabetes registers. The same indicators and variables were collected for each year. RESULTS: The response rate was 72.7%. Nationwide, 876 physicians participated in the review. From 1995 to 1997, there was a statistically significant improvement in the prevalence of performing all of the parameters for monitoring the primary care of diabetic patients. The process parameters showed a considerable improvement: the prevalence of recording weight increased from 35% of the diabetic patients in 1995 to 60% in 1997: the prevalence of conducting foot inspections increased from 40 to 63%; the prevalence of conducting fundus examinations increased from 38.5 to 68.3%; and the prevalence of measuring HbAlc values increased from 30.6 to 69.9%. As a result, metabolic control significantly improved: the percentage of diabetic patients with HbAlc concentration >9% decreased from 33.2% in 1995 to 22.5% in 1997; the percentage of diabetic patients with HbAlc concentration <7.4% increased from 45.1 to 50.5%. CONCLUSIONS: A major intervention plan based on quality assurance principles can improve physicians' performance on a national scale without the use of punitive administrative measures.

Blood Pressure↗

PubMed1992

Standardization of glycohemoglobin determinations in the clinical laboratory: three years of experience.

Measurement of glycohemoglobin has been recommended for the long-term assessment of glycemic control in diabetic patients. Because different analytical methods measure different glycohemoglobin species, it has been difficult to compare results between laboratories. Here we report 3 years of experience with calibration of an affinity chromatography method for measuring total glycohemoglobin (GHb). Calibration was achieved by including in each assay three hemolysate calibrators for which values for HbA1c and GHb had been determined by repeated analyses by high-performance liquid chromatography (HPLC) and affinity chromatography, respectively. Calibration improved interassay precision (CV = 3.20-7.90% and < 5.0% before and after the introduction of calibration, respectively) and eliminated lot-to-lot variability. In 91 samples, HbA1c was estimated by the calibrated affinity chromatography assay and measured by an ion-exchange HPLC method. Estimated and HPLC-measured HbA1c showed no clinically significant differences during 36 months. The high degree of long-term precision, the disappearance of lot-to-lot variability, and the excellent comparability between analytical methods measuring different species of glycated hemoglobins demonstrate the advantages of calibration.

Chromatography, Affinity↗

PubMed1989

Long-term study of normal kidneys transplanted into patients with type I diabetes.

We examined the rate of development of the lesions of diabetic nephropathy in transplanted kidneys residing for 6-14 yr in type I (insulin-dependent) diabetic kidney-allograft recipients. Although each recipient had end-stage diabetic nephropathy with his/her own kidneys, there was marked variability in the rate of development of mesangial expansion observed in the transplanted kidneys. The progression of glomerular pathology, including widening of the glomerular basement membrane and expansion of the mesangium, did not correlate significantly with several potential risk factors (e.g., donor source--cadaver or living related, histocompatibility match, age of the recipient or donor, age at onset of diabetes, duration of diabetes before renal failure, immunosuppressive drug dose, blood pressure, and severity of lesions of chronic rejection). However, there was a direct albeit imprecise relationship between the index of mesangial expansion at the final biopsy and the index of glycemic control (r = .61, P less than .01). These observations suggest that currently unknown factor(s) may modulate the progression of diabetic renal disease, even in a population that had uniformly demonstrated nephropathy risk. Our data support the hypothesis that in addition to glycemic control per se, there are risk factors intrinsic to the kidney itself.

Adolescent↗

PubMed2000

Predictors of abnormal cardiovascular autonomic function measured by frequence domain analysis of heart rate variability and conventional tests in patients with type 1 diabetes.

OBJECTIVE: Frequency domain analysis of heart rate variability (HRV) is used to assess cardiovascular autonomic function. There are no prospective data on the sensitivity of its various components to glycemia or other diabetes-related risk factors compared with conventional tests and with other complications of diabetes. RESEARCH DESIGN AND METHODS: In 1985, possible risk factors of future complications were determined in 115 children with type 1 diabetes. In 1996, the presence of complications (HRV analysis, conventional tests of autonomic function, urinary albumin excretion rate [UAER], and retinopathy) were assessed in 83 of these patients (age 32 +/- 1 years, duration of diabetes 22 +/- 1 years). RESULTS: Poor glycemic control (measured as lifetime glycemic exposure or HbA1c in 1985) was the most important independent predictor of decreases in all measures of absolute power of HRV (total power [TP] and very low frequency, low frequency [LF], and high frequency [HF] power) and square root of the mean square of R-R interval differences but not of changes of normalized measures or ratios (normalized HF and LF LF/HF). Other significant independent predictors of autonomic dysfunction were late age of onset of diabetes, female sex, and high BMI. To examine the sensitivity of the various tests to glycemia, the patients were divided into tertiles based on lifetime glycemic exposure (A1c months). Glycemic exposure in the tertiles averaged 194 +/- 25 A1c months (20 years of HbA1c 0.8% above normal), 556 +/- 19 A1c months(20 years of HbA1c 2.3% above normal), and 963 +/- 30 A1c months (20 years of HbA1c 4% above normal). Tests of complications that were significantly abnormal in patients already in the lowest tertile and were correlated with glycemia were TP and severity of retinopathy. Of conventional tests, only the ratio of length of R-R intervals during expiration to inspiration (E/I ratio) was significantly related to glycemic exposure, but it required high glycemic exposure (20 years of HbA1c 4% above normal) to be abnormal. UAER was significantly increased only in the highest tertile of glycemic exposure. CONCLUSIONS: TP and retinopathy score were much more sensitive to antecedent glycemia than conventional tests of autonomic function or UAER and were significantly abnormal in patients exposed to approximately 20 years' duration of an HbA1c 0.8% above normal.

Adult↗