Predictors of adverse outcomes and cost after surgical management for idiopathic normal pressure hydrocephalus: Analyses from a national database.

INTRODUCTION: We utilized a national administrative database to investigate drivers of immediate adverse economic and hospital outcomes, including non-routine discharge, prolonged length of stay (LOS), and admission costs among patients undergoing surgery for idiopathic normal pressure hydrocephalus (iNPH). METHODS: The National Inpatient Sample (NIS) was queried from 2007 to 2017 for patients aged ≥60 with a diagnosis code for iNPH undergoing surgery. Multivariable logistic-regression models and Wald χ2 were used to identify drivers of non-routine discharge, prolonged length of stay (LOS) (>75th percentile) and higher admission costs (>90th percentile). RESULTS: A total of 13,363 patients with iNPH undergoing surgical management were identified. The most common comorbidity reported in the cohort was a cardiovascular pathology (56.9 %, n = 7,787), followed by urinary pathology (37.2 %, n = 5,084), osteoarthritis (7.8 %, n = 1,071), Alzheimer's disease (4.6 %, n = 626) and cerebrovascular pathology (4.2 %, n = 569). The most frequently employed procedure was ventriculo-peritoneal (VP) shunt placement (65.6 %, n = 8,942) of which 89.8 % (n = 8,027) were performed open and 10.2 % (n = 915) laparoscopically. This was followed by lumbo-peritoneal (LP) shunting (15.5 %, n = 2,115), lumbar puncture alone (screened, serial CSF removal) (14.8 %, n = 2,013), endoscopic third ventriculostomy (ETV) (2%, n = 274), ventriculo-atrial (VA) shunt (0.95 %, n = 130) and ventriculo-pleural (Vpleural) shunt (0.46 %, n = 64). The median (IQR) LOS was 3 days (2-5), the rate of non-routine discharge was 37.3 % and median (IQR) cost was $11,230 ($7,735-15,590). On multivariable-analysis, emergent-admission (OR 2.91), older age (76-90: OR 1.55; 90+: OR 2.66), VP shunt (open: OR 3.09; laparoscopic: OR 2.32), ETV (OR 3.16), VA/VPleural shunt (OR 2.73) and hospital admission in Northeast-region compared to Midwest (OR 1.27) were found to be associated with increased risk of non-routine discharge. Some of the highly significant associated factors for prolonged LOS included emergent-admission (OR 11.34), ETV (OR 10.92), VA/VPleural shunt (OR 7.79) and open VP shunt (OR 8.24). For increased admission costs, some of the highly associated factors included VA/VPleural shunt (OR 18.48), laparoscopic VP shunt (OR 9.92), open VP shunt (OR 12.72) and ETV (OR 9.34). Predictor importance analysis revealed emergent admission, number of diagnosis codes (comorbidities) open VP shunt, hospital region, age] and revision or removal of shunt to be the most important drivers of these outcomes. CONCLUSION: Analyses from a national database indicate that among patients with iNPH, an emergent-admission may be the most significant risk-factor of adverse economic outcomes and higher costs.

Laparoscopic-Assisted Ventriculoperitoneal Shunt Placement and Reduction in Operative Time and Total Hospital Charges.

OBJECTIVE: In ventriculoperitoneal shunt (VPS) placement, distal placement of the peritoneal catheter will typically be performed by a neurosurgeon. More recently, laparoscopic-assisted (LA) placement of the distal peritoneal catheter by general surgeons has become common. The present study examined whether LA placement of a VPS (LAVPS) is associated with a reduced operative time, lower hospital costs, and fewer distal revisions. METHODS: A retrospective review was performed of the data from all patients who had received a new VPS at our institution from 2013 to 2016. Age, sex, diagnosis, previous abdominal surgery, operative time, anesthesia grade, incidence of 30-day shunt failure, and total hospital charges were analyzed. RESULTS: A total of 680 patients had undergone first-time VPS placement, including 199 with LAVPS and 481 with non-LAVPS placement (non-LAVPS). The mean age of the LAVPS patients was significantly older than that of the non-LAVPS patients (64.1 vs. 59.3 years; P = 0.002). The mean operative time was shorter in the LAVPS group than in the non-LAVPS group (55 vs. 75 minutes; P < 0.001). Distal shunt revision within 30 days occurred more often for the non-LAVPS patients (6 of 481 [1.2%]) than for the LAVPS patients (0 of 199 [0%]). A subset analysis of patients with normal-pressure hydrocephalus found decreased total hospital charges in the LAVPS group ($67,124 vs. $80,890; P = 0.009). CONCLUSIONS: Compared with non-LAVPS, LAVPS was associated with significantly shorter operative times and fewer distal shunt revisions within 30 days. The findings from a subset analysis supported a decrease in total hospital charges. Additional studies are needed; however, these data suggest that LAVPS is a safer, less-expensive alternative to non-LAVPS.

Shunt surgery in idiopathic normal pressure hydrocephalus is cost-effective-a cost utility analysis.

BACKGROUND: The objective was to evaluate the cost-effectiveness of shunt surgery in patients with idiopathic normal pressure hydrocephalus (iNPH). METHODS: Health-related quality of life was evaluated before and 6 months after surgery using the EQ-5D-3 L (EuroQOL group five-dimensions health survey) in 30 patients (median age, 71 years; range, 65-89 years) diagnosed with iNPH. The costs associated with shunt surgery were assessed by a detailed survey with interviews and extraction of register data concerning the cost of hospital care, primary care, residential care, home-care service and informal care. The cost of untreated patients was derived from the cost of dementia disorders in Sweden in 2012, as reported by the National Board of Health and Welfare. The cost effectiveness analysis used a decision-analytic Markov model. We used a societal perspective and a lifelong time horizon to estimate costs and effects. One-way sensitivity analysis and probabilistic sensitivity analysis were carried out to test the robustness of the model. RESULTS: The shunt surgery model as the standard treatment in iNPH resulted in a gain of 2.2 life years and 1.7 quality-adjusted life years (QALY), along with an incremental cost per patient of €7,500/QALY. The sensitivity analysis showed that the results were not sensitive to changes in uncertain parameters or assumptions. CONCLUSIONS: Shunt surgery in iNPH, an underdiagnosed condition severely impairing elderly patients, is not only an effective medical treatment, it is also cost-effective, adding 2.2 additional life years and 1.7 QALYs at a low cost, a remarkable gain for an individual aged around 70 years.

Cost-effectiveness analysis of shunt surgery for idiopathic normal pressure hydrocephalus based on the SINPHONI and SINPHONI-2 trials.

BACKGROUND: We showed that ventriculoperitoneal (VP) shunt and lumboperitoneal (LP) shunt surgeries are beneficial for patients with idiopathic normal pressure hydrocephalus (iNPH) in the Study of Idiopathic Normal Pressure Hydrocephalus on Neurological Improvement (SINPHONI; a multicenter prospective cohort study) and in SINPHONI-2 (a multicenter randomized trial). Although therapeutic efficacy is important, cost-effectiveness analysis is equally valuable. METHODS: Using both a set of assumptions and using the data from SINPHONI and SINPHONI-2, we estimated the total cost of treatment for iNPH, which consists of medical expenses (e.g., operation fees) and costs to the long-term care insurance system (LCIS) in Japan. Regarding the natural course of iNPH patients, 10% or 20% of patients on each modified Rankin Scale (mRS) show aggravation (aggravation rate: 10% or 20%) every 3 months if the patients do not undergo shunt surgery, as described in a previous report. We performed cost-effectiveness analyses for the various scenarios, calculating the quality-adjusted life year (QALY) and the incremental cost-effective ratio (ICER). Then, based on the definition provided by a previous report, we assessed the cost-effectiveness of shunt surgery for iNPH. RESULTS: In the first year after shunt surgery, the ICER of VP shunt varies from 29,934 to 40,742 USD (aggravation rate 10% and 20%, respectively) and the ICER of LP shunt varies from 58,346 to 80,392 USD (aggravation rate 10% and 20%, respectively), which indicates that the shunt surgery for iNPH is a cost-effective treatment. In the 2nd postoperative year, the cost to the LCIS will continue to decrease because of the lasting improvement of the symptoms due to the surgery. The total cost for iNPH patients will show a positive return on investment in as soon as 18 months (VP) and 21 months (LP), indicating that shunt surgery for iNPH is a cost-effective treatment. CONCLUSIONS: Because the total cost for iNPH patients will show a positive return on investment within 2 years, shunt surgery for iNPH is a cost-effective treatment and therefore recommended. The SINPHONI-2 study was registered with the University Hospital Medical Information Network Clinical Trials registry: UMIN000002730) SINPHONI was registered with ClinicalTrials.gov, no. NCT00221091.

Screening tests for normal-pressure hydrocephalus: sensitivity, specificity, and cost.

OBJECT: Many tests have been proposed to help choose candidates for shunt insertion in cases of suspected normal-pressure hydrocephalus (NPH). It is unclear what sensitivity and specificity a prospective test must have to improve outcomes, compared with the results of automatic shunt insertion. METHODS: The authors adapted the decision analysis model used in a companion article to allow for application of a screening test. Using the reported sensitivities and specificities of several such tests, they evaluated the effects such tests would have on the expected outcome of an average 65-year-old patient with moderate dementia. They also evaluated the cost-effectiveness of a theoretical screening test with superior sensitivity and specificity. CONCLUSIONS: Although external lumbar drainage comes quite close, none of the screening tests reported to date have sufficient sensitivity and specificity to improve expected outcome in an average candidate, compared with the results of automatic shunt placement in cases of suspected NPH. In addition, even a theoretically improved test would need to be considerably less expensive than prolonged lumbar drainage to be cost-effective in clinical practice.