Using patient-reported outcome measures for program evaluation: Design and findings on intention-to-treat outcomes from the Veterans Outcome Assessment survey.

The Veterans Outcomes Assessment (VOA) program surveys Veteran Health Administration (VHA) patients when they begin mental health treatment and at follow-up at three months to obtain patient-reported outcomes measures (PROM). It complements VA's evolving program in measurement-based care by providing additional data that can be useful for program evaluation including assessments of patients who have not been seen for ongoing mental health care. In principle, it provides data on intention-to-treat outcomes for program evaluation to complement the outcomes for patients who are receiving ongoing treatment that can be derived from measurement-based care. VOA findings confirm differences in outcomes between patients who have continued to be seen for treatment and those who have not. Patients in general mental health clinics with no encounters between the baseline and follow-up assessments who reported discontinuing care because they did not want or need treatment improved more, and those who discontinued due to problems improved less than those who remained in treatment. Experience with VOA has identified a number of issues that must be addressed before it is possible to use intention-to-treat outcomes for program evaluation.

Dynamic prediction of left ventricular assist device pump thrombosis based on lactate dehydrogenase trends.

AIMS: The risk of HeartMate II (HMII) left ventricular assist device (LVAD) thrombosis has been reported, and serum lactate dehydrogenase (LDH), a biomarker of haemolysis, increases secondary to LVAD thrombosis. This study evaluated longitudinal measurements of LDH post-LVAD implantation, hypothesizing that LDH trends could timely predict future LVAD thrombosis. METHODS AND RESULTS: From October 2004 to October 2014, 350 HMIIs were implanted in 323 patients at Cleveland Clinic. Of these, patients on 339 HMIIs had at least one post-implant LDH value (7996 total measurements). A two-step joint model combining longitudinal biomarker data and pump thrombosis events was generated to assess the effect of changing LDH on thrombosis risk. Device-specific LDH trends were first smoothed using multivariate boosted trees, and then used as a time-varying covariate function in a multiphase hazard model to analyse time to thrombosis. Pre-implant variables associated with time-varying LDH values post-implant using boostmtree were also investigated. Standardized variable importance for each variable was estimated as the difference between model-based prediction error of LDH when the variable was randomly permuted and prediction error without permuting the values. The larger this difference, the more important a variable is for predicting the trajectory of post-implant LDH. Thirty-five HMIIs (10%) had either confirmed (18) or suspected (17) thrombosis, with 15 (43%) occurring within 3 months of implant. LDH was associated with thrombosis occurring both early and late after implant (P < 0.0001 for both hazard phases). The model demonstrated increased probability of HMII thrombosis as LDH trended upward, with steep changes in LDH trajectory paralleling trajectories in probability of pump thrombosis. The most important baseline variables predictive of the longitudinal pattern of LDH were higher bilirubin, higher pre-implant LDH, and older age. The effect of some pre-implant variables such as sodium on the post-implant LDH longitudinal pattern differed across time. CONCLUSIONS: Longitudinal trends in surveillance LDH for patients on HMII support are useful for dynamic prediction of pump thrombosis, both early after implant and late. Incorporating upward and downward trends in LDH that dynamically update a model of LVAD thrombosis risk provides a useful tool for clinical management and decisions.

Too good to intervene? Thrombectomy for large vessel occlusion strokes with minimal symptoms: an intention-to-treat analysis.

INTRODUCTION: The minimal stroke severity justifying endovascular intervention remains elusive; however, a significant proportion of patients presenting with large vessel occlusion (LVO) and mild symptoms subsequently decline and face poor outcomes. OBJECTIVE: To evaluate our experience with these patients by comparing best medical therapy with thrombectomy in an intention-to-treat analysis. METHODS: Analysis of prospectively collected data of all consecutive patients with National Institutes of Health Stroke Scale (NIHSS) score ≤5, LVO on CT angiography, and baseline modified Rankin Scale (mRS) score 0-2 from November 2014 to May 2016. After careful discussion with patients/family, a decision to pursue medical or interventional therapy was made. Deterioration (development of aphasia, neglect, and/or significant weakness) triggered reconsideration of thrombectomy. The primary outcome measure was NIHSS shift (discharge NIHSS score minus admission NIHSS score). RESULTS: Of the 32 patients qualifying for the study, 22 (69%) were primarily treated with medical therapy and 10 (31%) intervention. Baseline characteristics were comparable. Nine (41%) medically treated patients had subsequent deterioration requiring thrombectomy. Median time from arrival to deterioration was 5.2 hours (2.0-25.0). Successful reperfusion (modified Treatment in Cerebral Infarction 2b-3) was achieved in all 19 thrombectomy patients. The NIHSS shift significantly favored thrombectomy (-2.5 vs 0; p<0.01). The median NIHSS score at discharge was low with both thrombectomy (1 (0-3)) and medical therapy (2 (0.5-4.5)). 90-Day mRS 0-2 rates were 100% and 77%, respectively (p=0.15). Multivariable linear regression indicated that thrombectomy was independently associated with a beneficial NIHSS shift (unstandardized ß -4.2 (95% CI -8.2 to -0.1); p=0.04). CONCLUSIONS: Thrombectomy led to a shift towards a lower NIHSS in patients with LVO presenting with minimal stroke symptoms. Despite the overall perception that this condition is benign, nearly a quarter of patients primarily treated with medical therapy did not achieve independence at 90 days.