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Background The Oncology Care Model (OCM) was developed as a payment model to encourage participating practices to provide better-quality care for cancer patients at a lower cost. The risk-adjustment model used in OCM is a Gamma generalized linear model (Gamma GLM) with log-link. The predicted value of expense for the episodes identified for our academic medical center (AMC), based on the model fitted to the national data, did not correlate well with our observed expense. This motivated us to fit the Gamma GLM to our AMC data and compare it with two other flexible modeling methods: Random Forest (RF) and Partially Linear Additive Quantile Regression (PLAQR). We also performed a simulation study to assess comparative performance of these methods and examined the impact of non-linearity and interaction effects, two understudied aspects in the field of cost prediction. Methods The simulation was designed with an outcome of cost generated from four distributions: Gamma, Weibull, Log-normal with a heteroscedastic error term, and heavy-tailed. Simulation parameters both similar to and different from OCM data were considered. The performance metrics considered were the root mean square error (RMSE), mean absolute prediction error (MAPE), and cost accuracy (CA). Bootstrap resampling was utilized to estimate the operating characteristics of the performance metrics, which were described by boxplots. Results RF attained the best performance with lowest RMSE, MAPE, and highest CA for most of the scenarios. When the models were misspecified, their performance was further differentiated. Model performance differed more for non-exponential than exponential outcome distributions. Conclusions RF outperformed Gamma GLM and PLAQR in predicting overall and top decile costs. RF demonstrated improved prediction under various scenarios common in healthcare cost modeling. Additionally, RF did not require prespecification of outcome distribution, nonlinearity effect, or interaction terms. Therefore, RF appears to be the best tool to predict average cost. However, when the goal is to estimate extreme expenses, e.g., high cost episodes, the accuracy gained by RF versus its computational costs may need to be considered.

Summary This study examined barriers to mental health service use and their demographic, medical, and psychosocial correlates among hematopoietic stem cell transplant (HSCT) survivors. A sample of 253 HSCT survivors who were 1- to 3-years post-transplant completed measures of demographic, physical, psychological, and social characteristics as well as a newly modified measure of barriers to mental health service use. Only 50% of distressed HSCT survivors had received mental health services. An exploratory factor analysis of the barriers to mental health service use scale yielded four factors: Scheduling Barriers, Knowledge Barriers, Emotional Barriers, and Illness-related Barriers. Patients with higher social constraints (perceived problems discussing the illness experience with significant others) reported higher levels of all four types of barriers. General distress and transplant-related posttraumatic stress symptoms were positively associated with emotional, knowledge, and illness-related barriers to mental health service use, whereas physical and functional well-being were inversely associated with these barriers. Having more knowledge barriers and more emotional barriers predicted a lower likelihood of receiving mental health services, as did lower levels of education and general distress. Results suggest that a significant number of HSCT survivors may benefit from education about mental health services that is tailored to individual barriers.

A patient with severe aplastic anemia underwent a matched unrelated bone marrow transplant, following which he developed a complex autoimmune syndrome. This featured transverse myelitis, immune mediated Coombs positive hemolytic anemia and immune thrombocytopenia (Evans syndrome), pulmonary infiltrates, eosinophilia, muscle pains and cramps and lichenoid dermatitis all of which may represent manifestations of graft-versus-host disease as they showed response to immunosuppression. Thus, although immune-mediated cytopenias after an allogeneic bone marrow transplant are rare, they should be considered as a possible cause of cytopenia in post-transplant patients.

Growth factor administration to donors prior to bone marrow (BM) harvesting results in an enrichment of the graft for myeloid precursors. In animals, growth factor-primed BM has a higher repopulating ability than untreated BM. Ten patients received an HLA-identical sibling, allogeneic transplant using granulocyte colony-stimulating factor (G-CSF)-stimulated BM. Stimulation consisted of G-CSF at 10 microg/kg/day for 2 days prior to harvest. Patients were transplanted for various benign and malignant hematological conditions. The GVHD prophylaxis consisted of cyclosporine, methotrexate and/or prednisone. Compared to untreated historical control BM, stimulated BM infusions contained similar number of nucleated cells (mean +/- s.d.: 3.5 +/- 1.5 vs 4.0 +/- 0.9 x 10(8)/kg), CD34+ cells (mean +/- s.d.: 7.5 +/- 3.0 vs 9.4 +/- 6.7 x 10(6)/kg), and CD3+ cells (mean +/- s.d.: 129 +/- 30 vs 190 +/- 59 x 10(6)/kg) but higher numbers of granulocyte-macrophage colony-forming units (mean +/- s.d.: 20 +/- 12 vs 96 +/- 34 x 10(4)/kg). Patients receiving stimulated BM had prompt and stable engraftment of white cells and platelets. On average they attained an ANC ofor = 1 x 10(9)/l 9 days earlier and a platelet count ofor = 20 x 10(9)/l 6 days earlier than historical controls receiving unstimulated HLA-identical sibling BM. Hospitalization was shortened by a mean of 10 days and transfusion requirements were modest. None of the patients developed severe GVHD or disease relapse. Two patients died of severe VOD post-BMT and thus were unevaluable for platelet engraftment. A third patient died of TTP on day 76 post-BMT. Seven patients are alive and well 49-585 days post-BMT. Stimulated BM may provide a valuable alternative to allogeneic BM and PBSC transplants. Ideal stimulation regimens need to be investigated.

Waldenstrom's disease is a lymphoproliferative disorder that is typically treated with plasmapheresis and/or alkylating agents. In young patients, other lymphoproliferative disorders have been treated with allogeneic transplantation. Two patients with aggressive Waldenstrom's disease, who progressed in spite of multi-agent chemotherapy and autologous stem cell transplantation, in one case, underwent allogeneic transplantation from their HLA-identical donors. Both remain alive with event-free survivals of more than 3, and more than 9 years, respectively. Allogeneic transplantation should be considered for young patients with Waldenstrom's disease.

Anemia is a common complication of autonomic failure and reduced red blood cell mass may contribute to the orthostatic hypotension of these patients. We investigated whether treatment with recombinant erythropoietin improves anemia and increases blood pressure in patients with primary autonomic failure. Three patients with multiple system atrophy and autonomic failure and one with pure autonomic failure were studied. All patients had normocytic normochromic anemia and low (n = 2) or normal (n = 2) serum levels of erythropoietin. Treatment with erythropoietin, 4000 U subcutaneously biweekly for 6 weeks, increased hematocrit and blood pressure in all patients. Hematocrit increased from 33.9 +/- 0.7 to 44.3 +/- 1.4%, blood pressure in supine position increased from 150 +/- 8/87 +/- 8 (systolic/diastolic; mean +/- SD) to 166 +/- 25/92 +/- 12 mmHg, and after 3 min in the head-up tilt position from 86 +/- 21/47 +/- 15 to 102 +/- 23/63 +/- 12 mmHg, (p < 0.05). All patients reported improvement in orthostatic symptoms and increased tolerance to standing. The study shows that treatment with erythropoietin improves anemia, increases blood pressure and ameliorates orthostatic hypotension in patients with primary autonomic failure.