Bone Mineral Density During and After Lactation: A Comparison of African American and Caucasian Women.

During lactation, changes in maternal calcium metabolism are necessary to provide adequate calcium for newborn skeletal development. The calcium in milk is derived from the maternal skeleton through a process thought to be mediated by the actions of parathyroid hormone-related protein (PTHrP) in combination with decreased circulating estrogen concentrations. After weaning, bone lost during lactation is rapidly regained. Most studies of bone metabolism in lactating women have been performed in Caucasian subjects. There are well-documented differences between African American (AA) and Caucasian (C) bone metabolism, including higher bone mineral density (BMD), lower risk of fracture, lower 25-hydroxyvitamin D (25(OH) D), and higher PTH in AA compared to C. In this prospective paired cohort study, BMD and markers of bone turnover were compared in self-identified AA and C mothers during lactation and after weaning. BMD decreased in both AA and C women during lactation, with similar decreases at the lumbar spine (LS) and greater bone loss in the C group at the femoral neck (FN) and total hip (TH), demonstrating that AA are not resistant to PTHrP during lactation. BMD recovery compared to the 2 week postpartum baseline was observed 6 months after weaning, though the C group did not have complete recovery at the FN. Increases in markers of bone formation and resorption during lactation were similar in AA and C. C-terminal telopeptide (CTX) decreased to 30% below post-pregnancy baseline in both groups 6 months after weaning, while procollagen type 1 N-terminal (P1NP) returned to baseline in the AA group and fell to below baseline in the C group. Further investigation is required to determine impacts on long term bone health for women who do not fully recover BMD before a subsequent pregnancy.

TRANSFER FROM PEDIATRIC TO ADULT ENDOCRINOLOGY.

OBJECTIVE: Adult and pediatric endocrinologists share responsibility for the transition of youth with type 1 diabetes from pediatric to adult healthcare. This study aimed to increase successful transfers to adult care in subspecialty practices by establishing a systematic health care transition (HCT) process. METHODS: Providers from the adult and pediatric endocrinology divisions at the University of Rochester Medical Center met monthly to customize and integrate the Six Core Elements (6CEs) of HCT into clinical workflows. Young adult patients with type 1 diabetes having an outpatient visit during a 34-month pre-post intervention period were eligible (N = 371). Retrospective chart review was performed on patients receiving referrals to adult endocrinology (n = 75) to obtain (1) the proportion of patients explicitly tracked during transfer from the pediatric to adult endocrinology practice, (2) the providers' documentation of the use of the 6CEs, and (3) the patients' diabetes control and healthcare utilization during the transition period. RESULTS: The percent of eligible patients with type 1 diabetes who were explicitly tracked in their transfer more than doubled compared to baseline (11% vs. 27% of eligible patients; P<.01). Pediatric providers started to use transition readiness assessments and create medical summaries, and adult providers increased closed-loop communication with pediatric providers after a patient's first adult visit. Glycemic control and healthcare utilization remained stable. CONCLUSION: Successful implementation of the 6CEs into pediatric and adult subspecialty practices can result in improvements of planned transfers of pediatric patients with type 1 diabetes to adult subspecialty providers. ABBREVIATIONS: 6CEs = six core elements; AYA = adolescent and young adult; DKA = diabetic ketoacidosis; ED = emergency department; HbA1c = hemoglobin A1c; HCT = health care transition.

SAFETY AND EFFICACY OF A PERI-OPERATIVE PROTOCOL FOR PATIENTS WITH DIABETES TREATED WITH CONTINUOUS SUBCUTANEOUS INSULIN INFUSION WHO ARE ADMITTED FOR SAME-DAY SURGERY.

OBJECTIVE: The number of people with diabetes using continuous subcutaneous insulin infusions (CSII) with an insulin pump has risen dramatically, creating new challenges when these patients are admitted to the hospital for surgical or other procedures. There is limited literature guiding CSII use during surgical procedures. METHODS: The study was carried out in a large, urban, tertiary care hospital. We enrolled 49 patients using insulin pump therapy presenting for 57 elective surgeries. We developed a CSII peri-operative glycemic management protocol (PGMP) to standardize insulin pump management in patients admitted to a same-day surgery unit (SDSU). The purpose was evaluate the safety (% capillary blood glucose (CBG) <70 mg/dL and/or pump incidents) and efficacy (first postoperative CBG ≤200 mg/dL) of the CSII PGMP. We determine the contribution of admission CBG, type of anesthesia, surgery length, and peri-operative steroid use on postoperative glycemic control. RESULTS: Overall, 63% of patients treated according to the CSII PGMP had a first postoperative CBG ≤200 mg/dL. There were no episodes of intra- or postoperative hypoglycemia. For patients treated with the CSII PGMP, the mean postoperative CBG was lower in patients with anticipated or actual surgical length ≤120 minutes (158.1 ± 53.9 vs. 216 ± 77.7 mg/dL, P<.01). No differences were observed with admission CBG, type of anesthesia, or steroid use. CONCLUSIONS: This study demonstrates that a CSII PGMP is both safe and effective for patients admitted for elective surgical procedures and provides an example of a standardized protocol for use in clinical practice.

Parathyroid hormone and parathyroid hormone-related protein analogs as therapies for osteoporosis.

Osteoporotic fractures result in significant morbidity and mortality. Anabolic agents reverse the negative skeletal balance that characterizes osteoporosis by stimulating osteoblast-dependent bone formation to a greater degree than osteoclast-dependent bone resorption. Parathyroid hormone (PTH) and parathyroid hormone- related protein (PTHrP) are peptide hormones, which have anabolic actions when administered intermittently. The only FDA-approved anabolic bone agent for the treatment of osteoporosis in the United States is PTH 1-34, or teriparatide, administered by daily subcutaneous injections. However, PTH 1-84 is also available in Europe. Synthetic human PTHrP 1-36 and a PTHrP 1-34 analog, BA058, have also been shown to increase lumbar spine bone density. These agents and several other PTH and PTHrP analogs, including some which are not administered as injections, continue to be investigated as potential anabolic therapies for osteoporosis.

Density dependent re-tuning of autoreactive T cells alleviates their pathogenicity in a lymphopenic environment.

Peripheral T cell tolerance is challenging to induce in partially lymphopenic hosts and this is relevant for clinical situations involving transplant tolerance. While the shortage of regulatory cells is thought to be one reason for this, T cell-intrinsic tolerance processes such as anergy are also poorly triggered in such hosts. In order to understand the latter, we used a T cell deficient mouse model system where adoptively transferred autoreactive T cells are significantly tolerized in a cell intrinsic fashion, without differentiation to regulatory T cells. Intriguingly these T cells often retain sufficient effector functions to trigger autoimmune pathology. Here we find that the high population density of the autoreactive T cells that accumulated in such a host limits the progression of the cell-intrinsic tolerance process in T cells. Accordingly, reducing the cell density during a second transfer allowed T cells to further tune down their responsiveness to antigenic stimulation. The retuning of T cells was reflected by a loss of the T cell's abilities to proliferate, produces cytokines or help B cells. We further suggest, based on altering the levels of chronic antigen using miniosmotic pumps, that the effects of cell-density on T cell re-tuning may reflect the effective changes in the antigen dose perceived by individual T cells. This could proportionally elicit more negative feedback downstream of the TCR. Consistent with this, the retuned T cells showed signaling defects both proximal and distal to the TCR. Therefore, similar to the immunogenic activation of T cells, cell-intrinsic T cell tolerance may also involve a quantitative and progressive process of tuning down its antigen-responsiveness. The progress of such tuning seems to be stabilized at multiple intermediate stages by factors such as cell density, rather than just absolute antigen levels.

A comparison of parathyroid hormone-related protein (1-36) and parathyroid hormone (1-34) on markers of bone turnover and bone density in postmenopausal women: the PrOP study.

Parathyroid hormone-related protein (PTHrP)(1-36) increases lumbar spine (LS) bone mineral density (BMD), acting as an anabolic agent when injected intermittently, but it has not been directly compared with parathyroid hormone (PTH)(1-34). We performed a 3-month randomized, prospective study in 105 postmenopausal women with low bone density or osteoporosis, comparing daily subcutaneous injections of PTHrP(1-36) to PTH(1-34). Thirty-five women were randomized to each of three groups: PTHrP(1-36) 400 µg/day; PTHrP(1-36) 600 µg/day; and PTH(1-34) 20 µg/day. The primary outcome measures were changes in amino-terminal telopeptides of procollagen 1 (PINP) and carboxy-terminal telopeptides of collagen 1 (CTX). Secondary measures included safety parameters, 1,25(OH)2 vitamin D, and BMD. The increase in bone resorption (CTX) by PTH(1-34) (92%) (p < 0.005) was greater than for PTHrP(1-36) (30%) (p < 0.05). PTH(1-34) also increased bone formation (PINP) (171%) (p < 0.0005) more than either dose of PTHrP(1-36) (46% and 87%). The increase in PINP was earlier (day 15) and greater than the increase in CTX for all three groups. LS BMD increased equivalently in each group (p < 0.05 for all). Total hip (TH) and femoral neck (FN) BMD increased equivalently in each group but were only significant for the two doses of PTHrP(1-36) (p < 0.05) at the TH and for PTHrP(1-36) 400 (p < 0.05) at the FN. PTHrP(1-36) 400 induced mild, transient (day 15) hypercalcemia. PTHrP(1-36) 600 required a dose reduction for hypercalcemia in three subjects. PTH(1-34) was not associated with hypercalcemia. Each peptide induced a marked biphasic increase in 1,25(OH)2 D. Adverse events (AE) were similar among the three groups. This study demonstrates that PTHrP(1-36) and PTH(1-34) cause similar increases in LS BMD. PTHrP(1-36) also increased hip BMD. PTH(1-34) induced greater changes in bone turnover than PTHrP(1-36). PTHrP(1-36) was associated with mild transient hypercalcemia. Longer-term studies using lower doses of PTHrP(1-36) are needed to define both the optimal dose and full clinical benefits of PTHrP. © 2013 American Society for Bone and Mineral Research.

Initiation of maintenance antiinflammatory medication in asthmatic children in a pediatric emergency department.

BACKGROUND: Despite National Asthma Education and Prevention Program guidelines recommending the use of daily controller medication in patients with persistent asthma, less than half of children requiring emergency department treatment for asthma exacerbations are receiving antiinflammatory therapy. OBJECTIVE: The purpose of this study was to evaluate a pediatric emergency department-based intervention designed to affect the prescribing practices of primary care physicians to better comply with national asthma guidelines. The intervention involved initiating maintenance antiinflammatory therapy in children with an asthma exacerbation who met guidelines for persistent disease but were not on antiinflammatory medications. METHODS: Guardians of children 2 to 18 years of age presenting to the pediatric emergency department with an asthma exacerbation were asked to complete an asthma survey. Patients were classified into severity categories. Those with persistent disease not on antiinflammatory medications were given a 2-week supply of medication and were instructed to follow-up with their primary care physicians to obtain a prescription for the antiinflammatory medication. Patient adherence information was obtained through telephone calls, pharmacy claims data, and physician office records. RESULTS: Forty-seven of 142 patients met criteria and were enrolled in the intervention. Seven patients were lost to follow-up. Of the remaining 40 patients, 28 followed-up with their primary care physician. Of these patients, 75% were continued on an antiinflammatory medication. Primary care physicians were significantly more likely to continue an antiinflammatory prescription in patients with severe persistent asthma (88.9% vs 68.4% of mild- or moderate-persistent asthmatics). Of the 28 patients who followed-up with their primary care physician, 13 had a prescription written, dispensed, and reported using the medication at the time of follow-up. CONCLUSIONS: Pediatric emergency department physicians can successfully partner with primary care physicians to implement national guidelines for children requiring maintenance antiinflammatory asthma therapy. Patient nonadherence continues to be a significant barrier for asthma management.