Performance of intermittently scanned continuous glucose monitoring systems in people with type 1 diabetes: A pooled analysis.

AIMS: To conduct a pooled analysis to assess the performance of intermittently scanned continuous glucose monitoring (isCGM) in association with the rate of change in sensor glucose in a cohort of children, adolescents, and adults with type 1 diabetes. MATERIAL AND METHODS: In this pooled analysis, isCGM system accuracy was assessed depending on the rate of change in sensor glucose. Clinical studies that have been investigating isCGM accuracy against blood glucose, accompanied with collection time points were included in this analysis. isCGM performance was assessed by means of median absolute relative difference (MedARD), Parkes error grid (PEG) and Bland-Altman plot analyses. RESULTS: Twelve studies comprising 311 participants were included, with a total of 15 837 paired measurements. The overall MedARD (interquartile range) was 12.7% (5.9-23.5) and MedARD differed significantly based on the rate of change in glucose (P < 0.001). An absolute difference of -22 mg/dL (-1.2 mmol/L) (95% limits of agreement [LoA] 60 mg/dL (3.3 mmol/L), -103 mg/dL (-5.7 mmol/L)) was found when glucose was rapidly increasing (isCGM glucose minus reference blood glucose), while a -32 mg/dL (1.8 mmol/L) (95% LoA 116 mg/dL (6.4 mmol/L), -51 mg/dL (-2.8 mmol/L)) absolute difference was observed in periods of rapidly decreasing glucose. CONCLUSIONS: The performance of isCGM was good when compared to reference blood glucose measurements. The rate of change in glucose for both increasing and decreasing glucose levels diminished isCGM performance, showing lower accuracy during high rates of glucose change.

Arterial cardiovascular risk factors and venous thrombosis: results from a population-based, prospective study (the HUNT 2).

BACKGROUND: An explanation for the increased risk of myocardial infarction and stroke in patients with venous thrombosis is lacking. The objective of this study was to investigate whether risk factors for arterial cardiovascular disease also increase the risk of venous thrombosis. DESIGN AND METHODS: Cases who had a first venous thrombosis (n=515) and matched controls (n=1,505) were identified from a population-based, nested, case-cohort study (the HUNT 2 study) comprising 71% (n=66,140) of the adult residents of Nord-Trøndelag County in Norway. RESULTS: The age- and sex-adjusted odds ratio of venous thrombosis for subjects with concentrations of C-reactive protein in the highest quintile was 1.6 (95% confidence interval: 1.2-2.2) compared to subjects with C-reactive protein in the lowest quintile. This association was strongest in subjects who experienced venous thrombosis within a year after blood sampling with a three-fold increased risk of participants in the highest versus the lowest quintile. Having first degree relatives who had a myocardial infarction before the age of 60 years was positively associated with venous thrombosis compared to not having a positive family history [odds ratio 1.3 (95% confidence interval: 1.1-1.6)]. Subjects with blood pressure in the highest quintile had half the risk of developing venous thrombosis compared to subjects whose blood pressure was in the lowest quintile. There were no associations between the risk of venous thrombosis and total cholesterol, low density lipoprotein-cholesterol, high density lipoprotein-cholesterol, triglycerides, glucose or smoking. We confirmed the positive association between obesity and venous thrombosis. CONCLUSIONS: C-reactive protein and a family history of myocardial infarction were positively associated with subsequent venous thrombosis. Blood pressure was inversely correlated to venous thrombosis. These findings should be confirmed by further investigations.

Prospective study of homocysteine and MTHFR 677TT genotype and risk for venous thrombosis in a general population--results from the HUNT 2 study.

This case-cohort designed study prospectively investigated whether elevated homocysteine levels measured in blood samples drawn before the event and methylenetetrahydrofolate reductase (MTHFR) gene polymorphism (MTHFR C677T) were associated with subsequent first venous thrombosis (VT) in a general population. Between August 1995 and June 1997, blood was collected from 66 140 people in the second Norwegian Health Study of Nord-Trøndelag (HUNT2). During a seven-year follow-up, 505 VT cases were identified. 1458 age- and sex-matched controls were selected from the original cohort. Serum total homocysteine (tHcy) and MTHFR genotype were measured in stored samples that were drawn a median of 33 months before the events. The overall odds ratio (OR) was 1.50 [95% confidence interval (CI) 0.97-2.30] for homocysteine levels above versus below the 95th percentile. There was no graded association with VT over quintiles of homocysteine. In men the OR was 2.17 (95% CI 1.20-3.91) for levels above versus below the 95th percentile, but no association was found in women (OR 1.00). Stratification by age, predisposing risk factors or time to event did not change these results. The MTHFR 677TT genotype was not related to risk for VT. In conclusion, elevated homocysteine levels in the general population predicted subsequent first VT in men but not in women.

Inflammatory cytokines as risk factors for a first venous thrombosis: a prospective population-based study.

BACKGROUND: In case-control studies, elevated levels of interleukins 6 and 8 have been found to be associated with an increased risk of venous thrombosis (VT). Because of the design of these studies, it remained uncertain whether these alterations were a cause or a result of the VT. In order to distinguish between the two, we set out to measure the levels of six inflammatory markers prior to thrombosis in a population-based cohort using a nested case-cohort design. METHODS AND FINDINGS: Between August 1995 and June 1997, blood was collected from 66,140 people in the second Norwegian Health Study of Nord-Trøndelag (HUNT2). We identified venous thrombotic events occurring between entry and 1 January 2002. By this date we had registered 506 cases with a first VT; an age- and sex-stratified random sample of 1,464 controls without previous VT was drawn from the original cohort. Levels of interleukins 1beta, 6, 8, 10, 12p70, and tumour necrosis factor-alpha were measured in the baseline sample that was taken 2 d to 75 mo before the event (median 33 mo). Cut-off points for levels were the 80th, 90th, and 95th percentile in the control group. With odds ratios ranging from 0.9 (95% CI: 0.6-1.5) to 1.1 (95% CI: 0.7-1.8), we did not find evidence for a relationship between VT and an altered inflammatory profile. CONCLUSIONS: The results from this population sample show that an altered inflammatory profile is more likely to be a result rather than a cause of VT, although short-term effects of transiently elevated levels cannot be ruled out.

Does AMH Reflect Follicle Number Similarly in Women with and without PCOS?

CONTEXT: Increased Anti-Mullerian Hormone in polycystic ovary syndrome, may be due to overactive follicles rather than reflect antral follicle count. OBJECTIVE: Does Anti-Mullerian Hormone reflect antral follicle count similarly in women with or without polycystic ovary syndrome or polycystic ovarian morphology? DESIGN: Cross-sectional, case-control. SETTING: Women who delivered preterm in 1999-2006. For each index woman, a woman with a term delivery was identified. PATIENTS: Participation rate was 69%. Between 2006-2008, 262 women were included, and diagnosed to have polycystic ovary syndrome, polycystic ovarian morphology or to be normal controls. INTERVENTION(S): Blood tests, a clinical examination and vaginal ultrasound. MAIN OUTCOME MEASURE(S): Anti-Mullerian Hormone/antral follicle count-ratio, SHBG, androstenedione and insulin, to test potential influence on the Anti-Mullerian Hormone/antral follicle count -ratio. RESULTS: Mean Anti-Mullerian Hormone/antral follicle count ratio in women with polycystic ovary syndrome or polycystic ovarian morphology was similar to that of the controls (polycystic ovary syndrome: 1,2 p = 0,10 polycystic ovarian morphology: 1,2, p = 0,27 Controls 1,3). Anti-Mullerian Hormone showed a positive linear correlation to antral follicle count in all groups. Multivariate analysis did not change the results. CONCLUSIONS: We confirmed the positive correlation between AMH and follicle count. Anti-Mullerian Hormone seems to be a reliable predictor of antral follicle count, independent of polycystic ovary syndrome diagnosis or ovarian morphology.

Thrombophilia, clinical factors, and recurrent venous thrombotic events.

CONTEXT: Data on the recurrence rate of venous thrombotic events and the effect of several risk factors, including thrombophilia, remain controversial. The potential benefit of screening for thrombophilia with respect to prophylactic strategies and duration of anticoagulant treatment is not yet known. OBJECTIVES: To estimate the recurrence rate of thrombotic events in patients after a first thrombotic event and its determinants, including thrombophilic abnormalities. DESIGN, SETTING, AND PATIENTS: Prospective follow-up study of 474 consecutive patients aged 18 to 70 years without a known malignancy treated for a first objectively confirmed thrombotic event at anticoagulation clinics in the Netherlands. The Leiden Thrombophilia Study (LETS) was conducted from 1988 through 1992 and patients were followed up through 2000. MAIN OUTCOME MEASURES: Recurrent thrombotic event based on thrombophilic risk factors, sex, type of initial thrombotic event (idiopathic or provoked), oral contraceptive use, elevated levels of factors VIII, IX, XI, fibrinogen, homocysteine, and anticoagulant deficiencies. RESULTS: A total of 474 patients were followed up for mean (SD) of 7.3 (2.7) years and complete follow-up was achieved in 447 (94%). Recurrence of thrombotic events occurred in 90 patients during a total of 3477 patient-years. The rate of thrombotic event recurrence was 25.9 per 1000 patient-years (95% confidence interval [CI], 20.8-31.8 per 1000 patient-years). The incidence rate of recurrence was highest during the first 2 years (31.9 per 1000 patient-years; 95% CI, 20.3-43.5 per 1000 patient-years). The risk of thrombotic event recurrence was 2.7 times (95% CI, 1.8-4.2 times) higher in men than in women. Patients whose initial thrombotic event was idiopathic had a higher risk of a thrombotic event recurrence than patients whose initial event was provoked (hazard ratio [HR], 1.9; 95% CI, 1.2-2.9). Women who used oral contraceptives during follow-up had a higher thrombotic event recurrence rate (28.0 per 1000 patient-years; 95% CI, 15.9-49.4 per 1000 patient-years) than those who did not (12.9 per 1000 patient-years; 95% CI, 7.9-21.2 per 1000 patient-years). Recurrence risks of a thrombotic event by laboratory abnormality ranged from an HR of 0.6 (95% CI, 0.3-1.1) in patients with elevated levels of factor XI to an HR of 1.8 (95% CI, 0.9-3.7) for patients with anticoagulant deficiencies. CONCLUSIONS: Prothrombotic abnormalities do not appear to play an important role in the risk of a recurrent thrombotic event. Testing for prothrombotic defects has little consequence with respect to prophylactic strategies. Clinical factors are probably more important than laboratory abnormalities in determining the duration of anticoagulation therapy.

Impact of thyrotropin receptor antibody levels on fetal development in two successive pregnancies in a woman with Graves' disease.

BACKGROUND: Treatment with radioiodine for Graves' disease regularly increases the level of antithyroid antibodies, and transplacental passage of stimulating thyrotropin receptor antibodies (TRAb) may cause fetal hyperthyroidism. CASE PRESENTATION: A 21-year-old woman with Graves' disease received radioiodine treatment to avoid use of antithyroid drugs in pregnancy. She became pregnant 4 months later and was euthyroid during pregnancy. In gestational week (GW) 33, she was admitted with an increased fetal heart rate of 176-180 beats/min. Fetal echocardiography indicated cardiac decompensation. The neonate had severe hyperthyroidism (free thyroxine >100 pmol/l, nv 12.0-22.0), cardiac insufficiency, insufficient weight gain, goiter and considerably accelerated skeletal age. In the mother and neonate, TRAb was >40 IU/l (nv <1.0), indicating transplacental passage of stimulating antibodies. After delivery, TRAb remained >40 IU/l in the woman, and 18 months later she underwent total thyroidectomy with subsequent decline in TRAb. In her next pregnancy, TRAb fluctuated between 38 and 17 IU/l, and repeated fetal ultrasound showed no goiter or sign of hyperthyroidism. In cord blood, TRAb was 10.9 IU/l, and the neonate had normal thyroid hormone levels. CONCLUSION: This case report illustrates the impact of maternal TRAb level for neonatal outcome in two successive pregnancies.