Nurse practitioner-led multidisciplinary teams to improve chronic illness care: The unique strengths of nurse practitioners applied to shared medical appointments/group visits

Purpose: To describe the roles of nurse practitioners (NPs) in a novel model of healthcare delivery for patients with chronic disease: shared medical appointments (SMAs)/group visits based on the chronic care model (CCM). To map the specific skills of NPs to the six elements of the CCM: self-management, decision support, delivery system design, clinical information systems, community resources, and organizational support.
Data sources: Case studies of three disease-specific multidisciplinary SMAs (diabetes, heart failure, and hypertension) in which NPs played a leadership role.
Conclusions: NPs have multiple roles in development, implementation, and sustainability of SMAs as quality improvement interventions. Although the specific skills of NPs map out all six elements of the CCM, in our context, they had the greatest role in self-management, decision support, and delivery system design.
Implications for practice: With the increasing numbers of patients with chronic illnesses, healthcare systems are increasingly challenged to provide necessary care and empower patients to participate in that care. NPs can play a key role in helping to meet these challenges.     

Use of latent growth curve models for assessing the effects of darbepoetin alfa on hemoglobin and fatigue

Background:The relationship between darbepoetin alfa and fatigue in chemotherapy-induced anemia (CIA) patients is complex because of patients receiving transfusions and the mediating effect of hemoglobin. Latent growth models (LGMs) were used to examine simultaneously relationships among drug exposure, fatigue outcomes, covariates, and mediating factors.Methods:Data from four CIA studies (AMG 20010145: small cell lung cancer, n = 547; AMG 980297: lung cancer, n = 288; AMG 20000161: lymphoproliferative malignancies, n = 339; AMG 20030232: non-myeloid malignancies, n = 320) were analyzed separately. Patients reported fatigue using the FACT-Fatigue. The effect of darbepoetin alfa on FACT-F changes mediated through hemoglobin changes was examined with LGMs controlling for transfusions, age, sex, baseline ECOG performance status, and health status (EQ-5D VAS). Model fit was assessed using multiple indices including the comparative fit index (CFI).Results:Darbepoetin alfa increased hemoglobin levels which were associated with decreases in fatigue. Increases in hemoglobin were statistically significantly (p < 0.05) related to decreases in fatigue in the studies (AMG 20030145: β? = 0.28; AMG 980297: β? = 0.46; AMG 20000161: β? = 0.59; and AMG 20030232: β? = 0.39). Darbepoetin alfa statistically significantly increased hemoglobin (AMG 20010145:β? = 0.50, AMG 980297:β? = 0.53, AMG 20000161:β? = 0.47, and AMG 20030232:β? = 0.30) while controlling for covariates. Model fit was acceptable (CFI ≥ 0.89) in all studies.Conclusions:Results indicate LGMs may be a valuable statistical method for modeling complex relationships among clinical and patient reported outcomes. A statistically significant effect of darbepoetin alfa on fatigue change through hemoglobin change occurred across four studies, after modeling the effects of transfusions, age, sex, EQ-5D VAS and ECOG.     

The utility of multidimensional assessments of physical health in patient care

Practitioners rely on a variety of measures of a patient's physical condition, including physiologic and clinician assessments. Occasionally, patient self-report data are collected. What insight into the physical health and functioning of patients does each of these types of information yield? This study suggests that each type of information provides a somewhat different insight into a patient's physical condition and that a combination of physiologic, clinician, and patient self-assessments can provide a more thorough assessment of a patient's condition. Using data from a clinical study of patients with heart failure, the Studies of Left Ventricular Dysfunction (SOLVD), measures of these three types of physical health assessments are compared as predictors of hospitalization. Results indicate that the self-report measures performed as well as or better than the physiologic or clinician assessments as predictors of hospitalization. The self-report measures have the added advantage of being inexpensive, noninvasive, and easily obtained over time, allowing for assessments of change. These findings suggest that, while related, each type of measure captures a different aspect of patient physical health and functioning.     

Identification of cell surface and secreted proteins essential for tumor cell survival using a genetic suppressor element screen

Survival factors play critical roles in regulating cell growth in normal and cancer cells. We designed a genetic screen to identify survival factors which protect tumor cells from apoptosis. A retroviral expression library of random cDNA fragments was constructed from cancer cells and used to transduce the colon carcinoma cell line HCT116. Recipient cells were functionally selected for induction of caspase 3-mediated apoptosis. Analyses of over 10,000 putative genetic suppression elements (GSEs) sequences revealed cognate gene candidates that are implicated in apoptosis. We further analysed 26 genes encoding cell surface and secreted proteins that can potentially serve as targets for therapeutic antibodies. Tetracycline-inducible GSEs from several gene candidates induced apoptosis in stable HCT 116 cell lines. Similar phenotypes were caused by RNAi derived from the same genes. Our data suggest requirement for the cell surface targets IGF2R, L1CAM and SLC31A1 in tumor cell growth in vitro, and suggests that IGF2R is required for xenograft tumor growth in a mouse model.     

Ribosomal DNA-directed PCR for identification of Achromobacter (Alcaligenes) xylosoxidans recovered from sputum samples from cystic fibrosis patients

The opportunistic human pathogen Achromobacter (Alcaligenes) xylosoxidans has been recovered with increasing frequency from respiratory tract culture of persons with cystic fibrosis (CF). However, confusion of this species with other closely related respiratory pathogens has limited studies to better elucidate its epidemiology, natural history, and pathogenic role in CF. Misidentification of A. xylosoxidans as Burkholderia cepacia complex is especially problematic and presents a challenge to effective infection control in CF. To address the problem of accurate identification of A. xylosoxidans, we developed a PCR assay based on a 16S ribosomal DNA sequence. In an analysis of 149 isolates that included 47 A. xylosoxidans and several related glucose-nonfermenting species recovered from CF sputum, the sensitivity and specificity of this PCR assay were determined to be 100 and 97%, respectively. The availability of this assay will enhance identification of A. xylosoxidans, thereby facilitating study of the pathogenic role of this species and improving infection control efforts in CF.     

Increased risk of lethal graft-versus-host disease-like syndrome after transplantation into NOD/SCID mice of human mobilized peripheral blood stem cells, as compared to bone marrow or cord blood

We tested the ability of human cells from different hematopoietic tissues to generate graft versus host disease-like syndrome (GVHD) in sublethally irradiated non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice. Tissue sources of human hematopoietic cells were: (1) bone marrow (BM), (2) nonmobilized peripheral blood (PB), (3) mobilized peripheral blood stem-progenitor cells (PBSC), and (4) cord blood (CB). To avoid interindividual donor variation, part of this study was done using BM, PB, and PBSC donated by a single healthy adult volunteer. A total of 179 NOD/SCID mice received graded human hematopoietic cell doses [5-500 x 10(6) mononuclear cells (MNC), containing 2-325 x 10(6) CD3(+) T cells, per mouse] from individual donors. Mice were observed for the development of GVHD and sacrificed 60 days after transplantation (earlier if ill). Mice were analyzed quantitatively by flow cytometry for human hematopoietic cell types and histologically, especially for human T lymphocytes infiltrating BM. No mouse transplanted with the tested doses of human CB or BM cells developed GVHD (experimentally defined as >10% human T lymphocytes infiltrating the mouse BM). For PB and PBSC, the frequencies of death, death with GVHD, and GVHD were directly related to the dose and source of human cells. Because PB cells contaminate harvested BM, the results from infused BM and PB were next combined for further analysis (BM/PB). The relative risks (hazard ratios estimated from the proportional hazards model) for death with GVHD, for each 10 human T cell dose increase, were 1.15 for BM/PB (p < 0.0001) and 1.47 for PBSC (p < 0.0001). In this in vivo xenogeneic model, the average T cell from human PBSC generated GVHD more potently than did the average T cell from human BM/PB, and the average CB T cell had a much lower GVHD potential. These results suggest that the potential for clinical GVHD from an HLA-disparate donor graft is likely to be quantitatively dependent both on the total number of T lymphocytes in the donor graft and the tissue source of the graft. Quantitative criteria for optimal T cell content of allogeneic donor hematopoietic grafts from different sources are discussed.     

Skin color, aging, and plasma L-dopa levels

Although plasma levels of L-dopa are derived substantially from catecholamine-synthesizing tissues, melanocytes--which produce L-dopa as part of the melanin synthetic cascade--also may be a source of circulating L-dopa. We compared plasma L-dopa levels in albino subjects and in Caucasian and Black normal volunteers and patients with essential hypertension. DOPA levels were similar among the subject groups. Among Caucasian normal volunteers, L-dopa levels were negatively correlated with subject age (r = -0.30, P less than 0.05), whereas norepinephrine levels tended to increase with subject age (r = 0.25, 0.05 less than P less than 0.10), so that the L-dopa:norepinephrine ratio was highly negatively correlated with subject age (r = -0.50, P less than 0.01). Skin pigmentation does not contribute importantly to plasma L-dopa levels in humans. In contrast with levels of norepinephrine, L-dopa levels appear to decrease during normal aging.