Management of patients with a neurovascular conflict involving the optic nerve and a non-diseased intracranial artery: Three cases.

Introduction: Determining whether a neurovascular conflict (NVC) involving the anterior visual pathway (AVP) and a non-diseased intracranial artery is amenable for microvascular decompression is challenging. Moreover, it is unclear whether microvascular decompression of the optic nerve is an effective therapy. Research question: What are the outcomes of different treatment strategies for NVCs involving the AVP and a non-diseased intracranial artery? Material and methods: Data on patients with symptomatic NVCs involving the AVP and a non-diseased intracranial artery was collected and included treatment and outcome parameters. The case series was drafted in accordance with the CARE guidelines. Results: Three patients aged 53,53 and 55 visited our out-patient clinic with a suspected symptomatic NVC between the optic nerve and a non-diseased intracranial artery. A conservative treatment was opted for in the first patient aimed at treating her glaucoma, with temporary improvement of symptoms. Microvascular decompression of the optic nerve was performed in two patients. One operated patient developed post-operative complications resulting in posterior circulation perfusion decline, while the other experienced a worse tunnel vision with a decrease in visual acuity. Discussion and conclusion: The diagnosis of a symptomatic NVC between the AVP and a non-diseased intracranial artery should be considered with caution, i.e. after exclusion of all other causes. Microvascular decompression can be performed but does not necessarily improve symptoms. A better understanding of the pathophysiological mechanisms underlying these NVCs is warranted to determine the benefit of microvascular decompression of the optic nerve.

Validity of the modified Rankin Scale in patients with aneurysmal subarachnoid hemorrhage: a randomized study.

PURPOSE: The modified Rankin Scale (mRS), a clinician-reported outcome measure of global disability, has never been validated in patients with aneurysmal subarachnoid hemorrhage (aSAH). The aims of this study are to assess: (1) convergent validity of the mRS; (2) responsiveness of the mRS; and (3) the distribution of mRS scores across patient-reported outcome measures (PROMs). METHODS: This is a prospective randomized multicenter study. The mRS was scored by a physician for all patients, and subsequently by structured interview for half of the patients and by self-assessment for the other half. All patients completed EuroQoL 5D-5L, RAND-36, Stroke Specific Quality of Life scale (SS-QoL) and Global Perceived Effect (GPE) questionnaires. Convergent validity and responsiveness were assessed by testing hypotheses. RESULTS: In total, 149 patients with aSAH were included for analysis. The correlation of the mRS with EQ-5D-5L was r = - 0.546, while with RAND-36 physical and mental component scores the correlation was r = - 0.439and r = - 0.574 respectively, and with SS-QoL it was r = - 0.671. Three out of four hypotheses for convergent validity were met. The mRS assessed through structured interviews was more highly correlated with the mental component score than with the physical component score of RAND-36. Improvement in terms of GPE was indicated by 83% of patients; the mean change score of these patients on the mRS was - 0.08 (SD 0.915). None of the hypotheses for responsiveness were met. CONCLUSION: The results show that the mRS generally correlates with other instruments, as expected, but it lacks responsiveness. A structured interview of the mRS is best for detecting disabling neuropsychological complaints. REGISTRATION: URL: https://trialsearch.who.int ; Unique identifier: NL7859, Date of first administration: 08-07-2019.

Inter-method reliability of the modified Rankin Scale in patients with subarachnoid hemorrhage.

BACKGROUND AND OBJECTIVES: The modified Rankin Scale (mRS) is one of the most frequently used outcome measures in trials in patients with an aneurysmal subarachnoid hemorrhage (aSAH). The assessment method of the mRS is often not clearly described in trials, while the method used might influence the mRS score. The aim of this study is to evaluate the inter-method reliability of different assessment methods of the mRS. METHODS: This is a prospective, randomized, multicenter study with follow-up at 6 weeks and 6 months. Patients aged ≥ 18 years with aSAH were randomized to either a structured interview or a self-assessment of the mRS. Patients were seen by a physician who assigned an mRS score, followed by either the structured interview or the self-assessment. Inter-method reliability was assessed with the quadratic weighted kappa score and percentage of agreement. Assessment of feasibility of the self-assessment was done by a feasibility questionnaire. RESULTS: The quadratic weighted kappa was 0.60 between the assessment of the physician and structured interview and 0.56 between assessment of the physician and self-assessment. Percentage agreement was, respectively, 50.8 and 19.6%. The assessment of the mRS through a structured interview and by self-assessment resulted in systematically higher mRS scores than the mRS scored by the physician. Self-assessment of the mRS was proven feasible. DISCUSSION: The mRS scores obtained with different assessment methods differ significantly. The agreement between the scores is low, although the reliability between the assessment methods is good. This should be considered when using the mRS in clinical trials. TRIAL REGISTRATION: www.trialregister.nl ; Unique identifier: NL7859.

The risk factors of 9-year follow-up on hypertension in middle-aged people in Tujia-Nationality settlement of China.

The aim of this study was to investigate the risk factors of hypertension in middle-aged people within the Tujia-Nationality settlement in China. Demographics questionnaires and fitness tests were performed to identify the risk factors of hypertension in middle-aged people in the years 2005, 2010 and 2014 in the area of southwest Hubei of China. Of the 2428 participants, 568 were classified as hypertensive, giving an overall occurrence of hypertension at 23.4%, and the prevalence of hypertension was the highest in the year 2014 (34.9%). Furthermore, Tujia minority had a significantly higher risk for having hypertension (odds ratio=1.055 with 95% confidence interval (CI): 1.039-1.072; P=0.001) than Han people. Individuals with the lowest level of cardiorespiratory fitness (CRF) had a 2.483-fold risk for hypertension (95% CI, 1.530-4.031; P=0.001). Obesity and overweight individuals increased the risk by 3.470-fold and 2.124-fold, respectively, for having hypertension compared to normal weight people. Finally, white-collar workers had a 58.1 and 31.8% higher risk for hypertension than blue-collar workers in rural and urban areas, respectively. These results demonstrated that the prevalence of hypertension was higher between 2011 and 2014 in the area. The main risk factors for developing hypertension were found to be sex (as woman), Tujia minority, white-collar workers, overweight-obese, those with a middle school education, and those with the lowest CRF.

Critical slowing down near the multiferroic phase transition in MnWO4.

By using broadband dielectric spectroscopy in the radio frequency and microwave range, we studied the magnetoelectric dynamics in the multiferroic chiral antiferromagnet MnWO_{4}. Above the multiferroic phase transition at T_{N2}≈12.6 K we observe a critical slowing of the corresponding magnetoelectric fluctuations resembling the soft-mode behavior in canonical ferroelectrics. This electric-field-driven excitation carries much less spectral weight than ordinary phonon modes. Also, the critical slowing down of this mode scales with an exponent larger than 1, which is expected for magnetic second-order phase transition scenarios. Therefore, the investigated dynamics have to be interpreted as the softening of an electrically active magnetic excitation, an electromagnon.

Vector chiral phases in the frustrated 2D XY model and quantum spin chains.

The phase diagram of the frustrated 2D classical and 1D quantum XY models is calculated analytically. Four transitions are found: the vortex unbinding transitions triggered by strong fluctuations occur above and below the chiral transition temperature. Vortex interaction is short range on small and logarithmic on large scales. The chiral transition, though belonging to the Ising universality class by symmetry, has different critical exponents due to nonlocal interaction. In a narrow region close to the Lifshitz point a reentrant phase transition between paramagnetic and quasiferromagnetic phase appears. Applications to antiferromagnetic quantum spin chains and multiferroics are discussed.

Considerable differences between methods for plasma D-dimer in the diagnosis of venous thrombosis: increased positive prediction using elevated discriminatory limits.

Four analytical methods for plasma D-dimer have been compared in a group of 82 consecutive patients with suspected venous thrombosis, 22 of whom subsequently received a positive clinical diagnosis. Differences in diagnostic power between methods were observed. In three of the four methods tested, the use of elevated discriminatory limits (rather than conventional 95-percentile upper reference limits) resulted in stronger positive predictive values for thromboembolism. We suggest that this approach may result in better diagnostic performance of the D-dimer method.

Validation of albumin determined in urine with the HemoCue point-of-care analyser.

Albumin concentrations persistently between 20 and 200 mg/L in first morning spot urine or urine collected overnight, referred to as microalbuminuria, indicate incipient nephropathy in diabetes mellitus. This study validates a new point-of-care device, the HemoCue Urine Albumin analyser, for handling, accuracy precision and predictive values (PV+/-) at 20 mg/L. Over a period of 2 months, 200 microalbuminuria samples were selected at the Department of Clinical Chemistry according to the results from the Integra 700 instrument (Roche, R) and analysed on the same day using the HemoCue analyser (HemoCue, H) and the Immage instrument (Beckman, B), in all cases closely following the manufacturers' instructions. Only 137 results were within the measuring range of H, 10-150 mg/L. Comparisons yielded regression lines H=1.06R-7.2 (r2=0.94), H=1.08B-3.1 (r2=0.94) and R=1.00B+4.3 (r2=0.99). Inter-assay (n=24) CV% at 12 mg/L was H=18.2, R=4.2 and B=2.9 and at 65 mg/L: H=6.1, R=1.8 and B=2.6. Intra-assay duplicate CV% for H at 21-40 mg/L was 13.2, at 41-80 mg/L 10.8 and at 81-150 mg/L 9.2. Intra-assay repeatability (n=8) CV% at 28 mg/L was 7.2-13.8, at 57 mg/L 6.4-8.4 and at 105 mg/L 4.3-7.1. External quality assurance urine albumin (B) was +5.7% cf. nephelometry and (R) +1.0% cf. turbidimetry (n=6) method-group means. PV+/- values were (H versus R) 0.98/0.37 and (H versus B) 0.95/0.65. HemoCue is easy to handle. Results below 20 mg/L need to be confirmed at the central laboratory to exclude microalbuminuria. Values above 20 mg/L can be used to follow microalbuminuria, as precision allows discerning steps of 10 mg/L.

Alkaline phosphatase activity: new assay for the Reflotron system. Results of the evaluation in eight clinical laboratories.

A new reagent carrier, Reflotron ALP, has been developed for the Reflotron system, allowing easy and rapid measurement (in less than 3 minutes) of alkaline phosphatase (ALP) activity in capillary blood, venous blood, heparinized plasma or serum. The evaluation of the analytical performance of the assay was carried out at eight clinical laboratories. The study of the imprecision using the measurements in human samples resulted in coefficients of variation ranging from 1.3% to 4.6% (within-run) and from 3.2% to 4.0% (day-to-day). The analytical specificity of the Reflotron ALP assay agrees well with ALP methods using a N-methyl-D-glucamine buffer solution. The calibration of the Reflotron ALP assay, however, is related to the reference intervals for ALP methods using a diethanolamine buffer solution. Method comparisons were performed with the ALP method on Hitachi instruments using diethanolamine buffer. Reflotron ALP measurements in blood and plasma in 157 randomly selected split samples showed excellent agreement (slope: 0.99; intercept: 0.7 U/l; median bias: 2.3%; median difference from the comparison method: -0.3%). Specimens from pregnant women and adolescents were excluded from this study. Differing values were obtained in a method comparison using 48 samples containing predominantly the ALP bone isoform (slope: 0.81; intercept: 31.5 U/l; median bias: 5.7%; median difference from the comparison method: -12.2%). Regression analysis of the results from 21 sera with prevailing placental ALP gave a slope of 1.51, and an intercept of -41.1 U/l (median bias: 8.6%; median difference from the comparison method: 35.6%). Reflotron ALP was compared with three different wet chemistry procedures using different buffer compounds: N-methyl-D-glucamine or diethanolamine or 2-amino-2-methyl-1-propanol. In samples containing predominantly ALP isoforms not of liver origin, the measurements with N-methyl-D-glucamine buffer gave the best fit with respect to Reflotron. In an interference study with 18 drugs, no effect on the test results could be detected. Total bilirubin up to 750 micromol/l and hemolysis up to 1.7 g/l free hemoglobin did not influence the test. Reflotron ALP proved to be an easy and rapid method with excellent precision. The accuracy related to an ALP method using diethanolamine buffer was good. The systematic differences for ALP in samples from pregnant women and adolescents have to be taken into account. The assay is well suited for differential diagnosis of hepatic diseases in decentralized testing.

Towards common reference intervals in clinical chemistry. An attempt at harmonization between three hospital laboratories in Skåne, Sweden.

The population sample of the Kristianstad survey, a reference intervals survey in the county of Kristianstad, was used to establish new reference intervals in clinical chemistry at the laboratories of the Central Hospital in Kristianstad, the University Hospital in Lund and the University Hospital in Mälmo. Three-hundred and fifty nine subjects, male and female, aged 20-80+ years, were invited to participate in the study, with a participation rate of 70%. Up to 70 analyses were performed on each subject, general clinical chemistry parameters in all three laboratories, specialized analyses where available. Separate a priori exclusion criteria were defined for each test. In addition, the test pattern of each individual was evaluated for signs of preclinical disease. Twelve cases of preclinical disease were discovered and clinically confirmed. Details on all test methods are presented along with information concerning instruments used, calibration procedures, methods of calculation and obtained reference intervals. Although the methods were in general calibrated against acknowledged reference materials, in some instances differences were found that made common reference intervals across all laboratories impossible. Problems relating to the practical use of international recommendations and the establishment of reliable reference intervals are discussed.

No impaired cognitive function in treated patients with mild-moderate hypertension compared to normotensive controls.

Hypertension is a predictor for impaired cognitive function and dementia in several prospective studies. It is currently under debate whether treatment of hypertension, and thus blood pressure lowering, is another risk factor for cognitive decline. We recruited a sample of 123 treated hypertensive patients and 76 normotensive controls, from a population-based study in primary health care, for screening of blood pressure, metabolic variables and cognitive function, as measured by the Mini-Mental State Examination (MMSE). Treated hypertensives had higher blood pressure but did not differ in cognitive function from the normotensives. Neither educational level nor metabolic variables confounded the findings. In conclusion, treated hypertensives did not differ in cognitive function from normotensive controls. This does not support the notion that pharmacological blood pressure reduction impairs cognitive function.

The increase of plasma homocysteine concentrations with age is partly due to the deterioration of renal function as determined by plasma cystatin C.

One of the main determinants of plasma homocysteine in healthy subjects is serum creatinine. In the present study, we therefore investigated the relation between plasma homocysteine concentration, serum creatinine and a new marker for glomerular filtration rate, plasma cystatin C concentration. Cystatin C reflects the glomerular filtration better than serum creatinine and is not related to the muscle mass and formation of creatinine. The study group consisted of 255 healthy subjects from a well-defined area in the southern part of Sweden. The concentration of plasma homocysteine was increased in men compared to women. This difference disappeared when men and women were stratified by serum creatinine values. Statistically significant correlations were noted between plasma homocysteine and age, plasma cystatin C and serum creatinine. It is shown that plasma homocysteine is not only correlated to serum creatinine as a result of renal function but also as a result of the relationship between homocysteine production and creatine-creatinine synthesis. Using linear regression we were able to show that plasma cystatin C had a higher explanatory value than age. Serum creatinine showed a lower explanatory power than age. The findings in the present study might suggest that the increase of plasma homocysteine concentration with age could be partly due to the deterioration of renal function.

Omega-3 Ethyl Ester Concentrate Decreases Total Apolipoprotein CIII and Increases Antithrombin III in Postmyocardial Infarction Patients.

This study investigated whether an ethyl ester preparation of fish oil (w-3) could normalise raised plasma concentrations of triglycerides, apolipoprotein CIII on apolipoprotein B-containing particles (LP CIII:B) found in patients with recent acute myocardial infarction. We also studied the effect of fish oil on antithrombin III levels. Out of 75 patients with a plasma triglyceride value >/=2.0 mmol/L, 22 normalised their triglycerides during diet and were therefore not randomised. The remaining patients were randomly assigned to 12 weeks' treatment with a daily dose of 4g w-3 or placebo. Mean plasma triglyceride concentrations were reduced by 24% from 3.10 +/- 1.15 (SD) to 2.53 +/- 0.94 mmol/L (p < 0.001) on w-3 (p < 0.001 vs placebo). The reduction was due to decreases in very low density lipoprotein concentrations. Total apolipoprotein CIII decreased significantly. This was due to reductions in LP CIII:non B concentrations, but the ratio LP CIII:non B/LP CIII:B was unaffected because of a slight insignificant decrease in LP CIII:B. The plasma triglyceride decreasing effect of w-3 could therefore not be due to redistribution of CIII between lipoproteins. Low density lipoprotein (LDL) cholesterol increased significantly with w-3 by 7%, and antithrombin III increased significantly with fish oil. In conclusion, w-3 had a moderate plasma triglyceride lowering effect and increased LDL cholesterol slightly, while antithrombin III increased in patients with hypertriglyceridaemia who had recently experienced a myocardial infarction.

Reference intervals for the glomerular filtration rate and cell-proliferation markers: serum cystatin C and serum beta 2-microglobulin/cystatin C-ratio.

Recent studies have indicated that serum and plasma cystatin C are better markers for glomerular filtration rate (GFR) than serum creatinine, ubiquitously used for this purpose. To fully exploit the value of serum and plasma cystatin C as GFR markers, reliable age and sex-correlated reference intervals are required. The present study comprised cystatin C determinations in plasma and sera from 259 individuals from a well-defined area in the southernmost part of Sweden. From demographic lists two men and two women were randomly selected from each one-year birth cohort above 20 years of age. No sex differences were found for plasma and serum cystatin C, whereas an increase in the cystatin C levels with age was noted, corresponding to the known age-related decrease in GFR. The following reference intervals are recommended for practical clinical use: S-Cystatin C (both sexes): 20-50 years, 0.70-1.21 mg l-1 and 50+ years, 0.84-1.55 mg l-1. The same samples were also used for determination of beta 2-microglobulin levels in order to calculate reference intervals for the beta 2-microglobulin/cystatin C-ratio, which is a more distinct marker for cell proliferation, particularly lymphoproliferation, than is the serum level of beta 2-microglobulin alone, since the ratio should be virtually uninfluenced by GFR. The beta 2-microglobulin/cystatin C-ratios were uninfluenced by sex and age and 1.45-2.43 is recommended as the serum reference interval for practical clinical use. Serum creatinine was determined in the same samples and the creatinine level was found to be strongly influenced by sex and weakly by age.

Islet hormone secretion in pancreatic cancer patients with diabetes.

The diabetes or impaired glucose tolerance that occurs in most patients with pancreatic cancer is characterized by profound insulin resistance. Recent evidence suggests that the diabetes may result from the presence of the tumor rather than being a predisposing factor to development of the malignancy. Some islet hormones have been shown to exhibit diabetogenic effects. To investigate the potential role of these hormones in the diabetic state associated with pancreatic cancer, we measured islet hormones during fasting in pancreatic cancer patients (n = 30), patients with other malignancies (n = 43), and healthy controls (n = 25). Preoperative pancreatic cancer patients were classified as normal glucose tolerance (NGTT), impaired glucose tolerance (IGTT), non-insulin-requiring diabetes (NIRD), and insulin-requiring diabetes (IRD). Nine pancreatic cancer patients were studied after tumor removal by subtotal pancreatectomy. Some preoperative pancreatic cancer patients (n = 19), postoperative patients (n = 9), and controls (n = 8) were also studied during hyperglycemia and following glucagon injection. Fasting plasma C-peptide was elevated in NIRD pancreatic cancer patients compared to controls. Fasting levels of islet amyloid polypeptide (IAPP), glucagon, and somatostatin were elevated in NIRD and IRD patients. IAPP and glucagon, but not somatostatin, normalized following subtotal pancreatectomy. During hyperglycemia, increases in C-peptide and IAPP were seen only in controls and in NGTT and postoperative pancreatic cancer patients. After glucagon infusion, IAPP levels increased in controls and nondiabetic cancer patients; C-peptide levels increased in controls, nondiabetic patients, and NIRD. Responses of C-peptide and IAPP to glucagon normalized after pancreatectomy. During hyperglycemia, glucagon levels fell in all groups except IGTT patients and a decrease in somatostatin concentrations was seen in controls.

Insulin resistance is not exhibited by advanced chronic obstructive pulmonary disease patients.

We have previously reported increased blood glucose concentrations and skeletal muscle glycogen depletion in severe COPD patients with chronic respiratory failure. In order to see if insulin resistance exists in severe COPD, we investigated nine patients with advanced COPD with chronic hypoxaemia and seven healthy control subjects of similar age, using the euglycaemic hyperinsulinaemic glucose clamp technique. We could not demonstrate a subnormal intravenous glucose requirement in response to insulin when maintaining euglycaemia in the COPD patients with chronic hypoxaemia. This indicates that the net metabolism of glucose in COPD patients with chronic hypoxaemia is not resistant to insulin.

Characterization of the insulin-antagonistic effect of growth hormone in insulin-dependent diabetes mellitus.

To characterize its insulin-antagonistic effect, growth hormone (GH) was infused at variable rates (24, 12 or 6 mU kg-1 min-1) for 1 h in 7 IDDM patients. Saline infusion was used as control (C) and all patients participated in all studies. The effect of insulin was measured with the euglycaemic clamp technique for 6 h combined with d-(3-3H)-glucose to evaluate glucose turnover. The insulin levels during the clamps were similar in all studies (23 +/- 3 mU l-1). The infusions produced peak GH levels of (24 rate = 24) 157 +/- 11, (12 rate = 12) 76 +/- 7, and (6 rate = 6) 45 +/- 8 mU l-1 (mean +/- SEM). The insulin-antagonistic effect of GH on glucose uptake was seen after 2 h and was at a maximum 4 to 5 h after the start of the GH infusion (difference in glucose infusion rate between C and 24 was 1.7 +/- 0.4 mg kg-1 min-1, p < 0.01). The resistance was due to a less pronounced effect of insulin to both inhibit rate of appearance and to stimulate rate of disappearance. Infusion of GH at 12 mU kg-1 min-1 induced a less pronounced insulin resistance both with regards to maximal effect (glucose infusion rate C - GH 1.4 +/- 0.5 mg kg-1 min-1, p < 0.05) and duration (3 h). At 6 mU kg-1 min-1, a clear GH-induced insulin-antagonistic effect was only seen during the third hour of the clamp (glucose infusion rate C-GH 1.3 +/- 0.5 mg kg-1 min-1, p < 0.05). GH infusion impaired the effect of insulin to lower both the levels of free fatty acids (NEFA) and glycerol between 2 and 5 h after the start of the infusion (NEFA, C:110 +/- 29, 24:303 +/- 95, p < 0.05: glycerol, C:32 +/- 4, 24:50 +/- 7 mumol l-1, p < 0.05). The present study therefore demonstrates that the insulin-antagonistic effect of GH in IDDM is related to the plasma levels both with regard to duration and response. The results also indicate that GH impairs the effect of insulin on lipolysis in IDDM after physiological peaks.

Fat metabolism and its response to infusion of insulin and glucose in patients with advanced chronic obstructive pulmonary disease.

In order to investigate fat metabolism and the regulation of lipolysis and blood fuel metabolites by insulin, nine patients with chronic obstructive pulmonary disease (COPD) with chronic hypoxaemia and seven healthy control subjects of similar age were investigated by determination of the turnover rate of free fatty acids (TOR), using 1-14C-oleic acid as a tracer, and arterial concentrations of FFA, glycerol and 3-hydroxybutyrate. The measurements were performed in the basal state and during insulin and glucose infusion, aiming at euglycaemia at insulin levels of 50 and 100 mU l-1. The subjects' ages were 64 +/- 2.7 and 66 +/- 1.1 (mean +/- SEM) years in the COPD and control groups, respectively. TOR was 0.73 +/- 0.06 and 0.52 +/- 0.02 mmol min-1 (P < 0.05) in the basal state, 0.33 +/- 0.04 and 0.30 +/- 0.02 at an insulin level of 50 mU l-1 and 0.32 +/- 0.08 and 0.24 +/- 0.02 at an insulin level of 100 mU l-1, in the COPD and control groups, respectively. Arterial FFA concentration was 0.98 +/- 0.08 and 0.75 +/- 0.06 mmol l-1 (P < 0.05) in the basal state in the COPD and control groups, respectively. During the clamp, the decrease in FFA mirrored that in TOR. The results show that the state of lipolysis is increased in severe COPD patients with chronic hypoxaemia. Furthermore, the results suggest a reduced effect of insulin in lipolysis.

Regulation of insulin-like growth factor binding protein-1 (IGFBP-1) in insulin-dependent diabetes mellitus. Effects of hyperglycaemia and insulin.

The aim of the present study was to characterize the effect of 44 h of hyperglycaemia on diurnal levels of insulin-like growth factor binding protein-1 (IGFBP-1), insulin-like growth factor-1 (IGF-1), growth hormone (GH) and glucagon in 7 well-controlled subjects with insulin-dependent diabetes mellitus (IDDM). Hyperglycaemia (approximately 15 mmol/l) was induced by a glucose infusion, while the degree of insulinisation was similar to that of a corresponding period with near normoglycaemia (approximately 6.9 mmol/l). Hyperglycaemia for 44 h did not alter the normal diurnal IGFBP-1 levels when the degree of insulinisation was unchanged. The diurnal secretion pattern of IGFBP-1 was preserved in both genders and without any difference between the control and hyperglycaemic periods. However, the IGFBP-1 levels were increased in these IDDM subjects despite a peripheral hyperinsulinemia. An inverse correlation was found between IGFBP-1 and peripheral insulin levels both during periods of rapid changes in IGFBP-1 and insulin concentrations (i.e. morning hours) as well as during the total 24-h sampling period. Total IGF-1 levels were low, but no further decrease was seen after 24 h of hyperglycaemia in the presence of unchanged insulin levels. In conclusion, the present study clearly shows that the increased IGFBP-1 level seen during poor metabolic control in IDDM is not caused by hyperglycaemia. Glucose levels per se do not influence either total IGF-1 or IGFBP-1 concentrations in well-insulinised diabetic patients.