Cost-effectiveness of bariatric surgery and non-surgical weight management programmes for adults with severe obesity: a decision analysis model

OBJECTIVES

To determine the most cost-effective weight management programmes (WMPs) for adults, in England with severe obesity (BMI ≥ 35 kg/m2), who are more at risk of obesity related diseases.

METHODS

An economic evaluation of five different WMPs: 1) low intensity (WMP1); 2) very low calorie diets (VLCD) added to WMP1; 3) moderate intensity (WMP2); 4) high intensity (Look AHEAD); and 5) Roux-en-Y gastric bypass (RYGB) surgery, all compared to a baseline scenario representing no WMP. We also compare a VLCD added to WMP1 vs. WMP1 alone. A microsimulation decision analysis model was used to extrapolate the impact of changes in BMI, obtained from a systematic review and meta-analysis of randomised controlled trials (RCTs) of WMPs and bariatric surgery, on long-term risks of obesity related disease, costs, quality adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) measured as incremental cost per QALY gained over a 30-year time horizon from a UK National Health Service (NHS) perspective. Sensitivity analyses explored the impact of long-term weight regain assumptions on results.

RESULTS

RYGB was the most costly intervention but also generated the lowest incidence of obesity related disease and hence the highest QALY gains. Base case ICERs for WMP1, a VLCD added to WMP1, WMP2, Look AHEAD, and RYGB compared to no WMP were £557, £6628, £1540, £23,725 and £10,126 per QALY gained respectively. Adding a VLCD to WMP1 generated an ICER of over £121,000 per QALY compared to WMP1 alone. Sensitivity analysis found that all ICERs were sensitive to the modelled base case, five year post intervention cessation, weight regain assumption.

CONCLUSIONS

RYGB surgery was the most effective and cost-effective use of scarce NHS funding resources. However, where fixed healthcare budgets or patient preferences exclude surgery as an option, a standard 12 week behavioural WMP (WMP1) was the next most cost-effective intervention.

[POEMS syndrome: Diagnosis, stratification, treatments]

POEMS syndrome is a rare form of B-cell dyscrasia with multiple clinical signs including the acronym for polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes. It is a paraneoplastic syndrome due to an underlying plasma cell disorder belonging to the monoclonal gammopathies of clinical significance (MGCS). The major criteria for this syndrome are polyradiculoneuropathy, clonal plasma cell disorder (PCD), sclerotic bone lesions, elevated vascular endothelial growth factor (VEGF), and the presence of Castleman's disease. Minor features include organomegaly, endocrinopathy, skin changes, papilledema, extravascular volume over-load, and thrombocytosis. The diagnosis of POEMS syndrome requires three of the major criteria, two of which must include polyradiculoneuropathy and clonal PCD, and at least one of the minor criteria. VEGF plays a major role in the disease although anti-VEGF treatments have been disappointing. Risk stratification is based on clinical phenotype rather than specific molecular markers. Depending on bone marrow involvement and the number of sclerotic bone lesions, first line therapy should be irradiation or systemic therapy. For patients with a dominant sclerotic plasmacytoma, first line therapy is irradiation. Patients with diffuse sclerotic lesions or disseminated bone marrow involvement and for those who have progression of their disease 3 to 6 months after completing irradiation therapy should receive antiplasma cell systemic therapy, the most effective being high dose chemotherapy with autologous stem cell transplantation. Lenalidomide seems to have a high efficacy with manageable toxicity. Thalidomide and proteasome inhibitors like bortezomib are also effective, but their benefit needs to be weighed against their risk of exacerbating the peripheral neuropathy.

[Aneurysm of the portal venous system: A rare and unknown pathology]

INTRODUCTION

Portal vein aneurysms are rare, representing 3% of venous aneurysms, with about 200 cases described in the literature, probably underestimated.

CASE REPORT

A 66-year-old man, suspect of splenomegaly, underwent an abdominal ultrasound and a thoraco-abdomino-pelvic CT scan showing a 40mm portal vein aneurysm. Final diagnosis was T-cell hemopathy. Five and six months later, abdominal imaging was stable, suggesting congenital origin due to lack of obliteration of the vitelline vein.

CONCLUSION

Portal vein aneurysms are often asymptomatic and an incidental finding. Monitoring is recommended because of their potential complications (thrombosis, rupture of aneurysm, portal hypertension, adjacent organs compression), annually if asymptomatic or more frequently with sometimes a surgical management in case of clinical manifestations.

Neurotensin receptor type 2 protects B-cell chronic lymphocytic leukemia cells from apoptosis

B-cell chronic lymphocytic leukemia (B-CLL) cells are resistant to apoptosis, and consequently accumulate to the detriment of normal B cells and patient immunity. Because current therapies fail to eradicate these apoptosis-resistant cells, it is essential to identify alternative survival pathways as novel targets for anticancer therapies. Overexpression of cell-surface G protein-coupled receptors drives cell transformation, and thus plays a critical role in malignancies. In this study, we identified neurotensin receptor 2 (NTSR2) as an essential driver of apoptosis resistance in B-CLL. NTSR2 was highly expressed in B-CLL cells, whereas expression of its natural ligand, neurotensin (NTS), was minimal in both B-CLL cells and patient plasma. Surprisingly, NTSR2 remained in a constitutively active phosphorylated state, caused not by a mutation-induced gain-of-function but rather by an interaction with the oncogenic tyrosine kinase receptor TrkB. Functional and biochemical characterization revealed that the NTSR2-TrkB interaction acts as a conditional oncogenic driver requiring the TrkB ligand brain-derived neurotrophic factor (BDNF), which unlike NTS is highly expressed in B-CLL cells. Together, NTSR2, TrkB and BDNF induce autocrine and/or paracrine survival pathways that are independent of mutation status and indolent or progressive disease course. The NTSR2-TrkB interaction activates survival signaling pathways, including the Src and AKT kinase pathways, as well as expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL. When NTSR2 was downregulated, TrkB failed to protect B-CLL cells from a drastic decrease in viability via typical apoptotic cell death, reflected by DNA fragmentation and Annexin V presentation. Together, our findings demonstrate that the NTSR2-TrkB interaction plays a crucial role in B-CLL cell survival, suggesting that inhibition of NTSR2 represents a promising targeted strategy for treating B-CLL malignancy.

[Classification and therapeutic management of monoclonal gammopathies of renal significance]

Two categories of renal disorders associated with monoclonal gammopathies are to be distinguished, according to the characteristics of the underlying B-cell clone. The first group of renal diseases always occurs in the setting of high tumor mass with production of large amounts of monoclonal immunoglobulins. The main complication is the so-called myeloma cast nephropathy, which almost invariably complicates high tumor mass myeloma. The second group includes all renal disorders caused by a monoclonal immunoglobulin secreted by a nonmalignant B-cell clone, and currently referred as a "monoclonal gammopathy of renal significance (MGRS)". This term was introduced to distinguish monoclonal gammopathies that are responsible for the development of kidney damage from those that are truly benign. The spectrum of renal diseases in MGRS is wide and its classification relies on the localization of renal lesions, either glomerular or tubular, and on the pattern of ultrastructural organization of immunoglobulin deposits. Physicochemical characteristics of the pathogenic monoclonal immunoglobulin are probably involved in their propensity to deposit or precipitate in the kidney, as illustrated by the high rate of recurrence of each specific type after kidney transplantation. Early diagnosis and efficient chemotherapy targeting the causal B-cell clone are mandatory to improve renal prognosis and patient survival.

International prognostic index, type of transplant and response to rituximab are key parameters to tailor treatment in adults with CD20-positive B cell PTLD: clues from the PTLD-1 trial

Tailoring treatment by patient strata based on the risk of disease progression and treatment toxicity might improve outcomes of patients with posttransplant lymphoproliferative disorder (PTLD). We analysed the cohort of 70 patients treated in the international, multicenter phase II PTLD-1 trial (NCT01458548) to identify such factors. Of the previously published scoring systems in PTLD, the international prognostic index (IPI), the PTLD prognostic index and the Ghobrial score were predictive for overall survival. None of the scoring systems had a considerable effect on the risk for disease progression. Age and ECOG performance status were the baseline variables with the highest prognostic impact in the different scoring systems. Baseline variables not included in the scoring systems that had an impact on overall survival and disease progression were the type of transplant and the response to rituximab at interim staging. Thoracic organ transplant recipients who did not respond to rituximab monotherapy were at particularly high risk for death from disease progression with subsequent CHOP-based chemotherapy. Patients in complete remission after four courses of rituximab and patients in partial remission with low-risk IPI had a low risk of disease progression. We speculate that chemotherapy might not be necessary in this patient cohort.