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Periprocedural hyperglycemia is an independent predictor of mortality in patients who underwent percutaneous coronary intervention (PCI). However, periprocedural management of blood glucose is not standardized. The effects of routinely continuing long-acting glucose-lowering medications before coronary angiography with possible PCI on periprocedural glycemic control have not been investigated. Patients with diabetes mellitus (DM; n = 172) were randomized to continue (Continue group; n = 86) or hold (Hold group; n = 86) their clinically prescribed long-acting glucose-lowering medications before the procedure. The primary end point was glucose level on procedural access. In a subset of patients (no DM group: n = 25; Continue group: n = 25; and Hold group: n = 25), selected measures of platelet activity that change acutely were assessed. Patients with DM randomized to the Continue group had lower blood glucose levels on procedural access compared with those randomized to the Hold group (117 [97 to 151] vs 134 [117 to 172] mg/dl, p = 0.002). There were two hypoglycemic events in the Continue group and none in the Hold group, and no adverse events in either group. Selected markers of platelet activity differed across the no DM, Continue, and Hold groups (leukocyte platelet aggregates: 8.1% [7.2 to 10.4], 8.7% [6.9 to 11.4], 10.9% [8.6 to 14.7], p = 0.007; monocyte platelet aggregates: 14.0% [10.3 to 16.3], 20.8% [16.2 to 27.0], 22.5% [15.2 to 35.4], p <0.001; soluble p-selectin: 51.9 ng/ml [39.7 to 74.0], 59.1 ng/ml [46.8 to 73.2], 72.2 ng/ml [58.4 to 77.4], p = 0.014). In conclusion, routinely continuing clinically prescribed long-acting glucose-lowering medications before coronary angiography with possible PCI help achieve periprocedural euglycemia, appear safe, and should be considered as a strategy for achieving periprocedural glycemic control.

BACKGROUND: HIV infection has been associated with dyslipidemia, insulin resistance, and changes in body composition, including loss of subcutaneous fat and skeletal muscle, with relative sparing of upper trunk and visceral fat. Because of its resemblance to Cushing's syndrome, caused by glucocorticoid excess, we hypothesized that variations in the glucocorticoid receptor (GR) gene, associated with changes in sensitivity to glucocorticoids, may be associated with such abnormalities in HIV-infected patients. DESIGN: This was a cross-sectional genetic association study. MATERIALS AND METHODS: GR polymorphisms were determined in HIV-infected participants from the study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM). We created haplotypes in 754 participants and assessed the associations with fasting metabolic parameters and body composition by MRI. RESULTS: After stratification for ethnicity, we found no consistent pattern of associations between the described GR haplotypes and body composition or metabolic parameters in HIV-infected patients. However, we found a new haplotype comprising the Tth111I polymorphism in African-Americans. Heterozygous carriers of this haplotype (n=24) had significantly higher levels of high-density lipoprotein cholesterol compared with age-matched and sex-matched noncarriers (n=96) (median 55 vs. 44 mg/dl, P=0.026) and a tendency toward lower glucose (-5 mg/dl) and triglyceride (-21 mg/dl) levels and lower visceral adipose tissue mass (-0.22 l). CD4 count as well as skeletal muscle mass were also lower in carriers of this haplotype (-154 cells/mul and -1.6 l, respectively). CONCLUSION: Although our cohort included only a small number of carriers of the new Tth111I haplotype, these results are suggestive that this GR haplotype may be associated with a healthier metabolic profile in African-Americans with HIV infection.

Tumors of mesenchymal and epithelial origin produce IGF-2, which activates pathways in the tumors. In a minority of patients, the tumors (hepatomas, fibromas, and fibrosarcomas are the most common among many) release into the circulation enough IGF-2-related peptides to mimic the fasting hypoglycemia characteristic of patients with insulin-producing islet-cell tumors. Rarely, markedly elevated IGF-2 levels produce somatic changes suggestive of acromegaly. Typically, the elevated IGF-2 levels are associated with suppressed plasma levels of insulin, IGF-1, and GH. Complicating the pathophysiology are the IGF binding proteins (IGFBPs) that can bind IGF-2 and IGF-1, modifying hormone metabolism and action. IGFBP concentrations are often altered in the presence of these tumors. At the cellular level, the 3 hormone-related ligands, IGF-2, IGF-1, and insulin, all bind to 4 (or more) types of IGF-1 receptor (IGF-1R) and insulin receptor (IR). Each receptor has its own characteristic affinity for each ligand, a tyrosine kinase, and overlapping profiles of action in the target cells. The IGF-2R, in addition to binding mannose-6-phosphate-containing proteins, provides an IGF-2 degradation pathway. Recent evidence suggests IGF-2R involvement also in signal transduction. Surgery, the treatment of choice, can produce a cure. For patients not cured by surgery, multiple therapies exist, for the tumor and for hypoglycemia. Potential future therapeutic approaches are sketched. From 1910 to 1930, hypoglycemia, insulin, insulinomas, and non-islet-cell tumors were recognized. The latter third of the century witnessed the emergence of the immunoassay for insulin; the IGFs, their binding proteins, and assays to measure them; and receptors for the insulin-related peptides as well as the intracellular pathways beyond the receptor. In closing, we replace non-islet-cell tumor hypoglycemia, an outdated and misleading label, with IGF-2-oma, self-explanatory and consistent with names of other hormone-secreting tumors.

HbA1c testing has become an accepted means of diagnosing diabetes, as an alternative to blood glucose levels. However, population based norms of glucose and of HbA1c levels do not enable the detection of diabetes at an early enough stage to thwart complications. Personal trajectories of glucose levels show steep increases a number of years prior to diabetes diagnosis. Here, we hypothesize that a comparable time-dependent deviation in an individual's HbA1c level may be an early manifestation of disease that should prompt lifestyle modifications. We predict that analysis of personal trajectories of glucose and of HbA1c will promote earlier intervention and a greater reduction in disease complications, than do current standards, which are based on population based norms