Umer Akbar
Brown University
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Radiotherapy and Oncology | 2009
J. Zhou; Charles C. Hsu; Jordan M. Winter; Timothy M. Pawlik; Daniel A. Laheru; Michael A. Hughes; Ross C. Donehower; Christopher L. Wolfgang; Umer Akbar; Richard D. Schulick; John L. Cameron; Joseph M. Herman
BACKGROUND AND PURPOSE To examine the role of adjuvant chemoradiation (CRT) in patients with resected ampullary adenocarcinoma. MATERIALS AND METHODS The records of patients who underwent curative surgery for ampullary adenocarcinoma at a single institution between 1992 and 2007 were reviewed. Final analysis included 111 patients, 45% of which also received adjuvant CRT. RESULTS Median overall survival (OS) was 36.2 months for all patients. Adverse prognostic factors for OS included T stage (T3/4 vs. T1/T2, p=0.046), node status (positive vs. negative, p<0.001), and histological grade (grade 3 vs. 1/2, p=0.09). Patients receiving CRT were more likely to have advanced T-stage (p=0.001), node positivity (p<0.001), and poor histologic grade (p=0.015). Patients who received CRT were also significantly younger (p=0.001). On univariate analysis, adjuvant CRT failed to result in a significant difference in survival when compared to surgery alone (median OS: 33.4 vs. 36.2 months, p=0.969). Patients with node-positive resections who underwent CRT had a non-significant improvement in survival (median OS: 21.6 vs. 13.0 months, p=0.092). Thirty-three percent of patients developed distant metastasis. Common sites of distant metastasis included liver (23%) and peritoneum (7%). CONCLUSIONS Adjuvant chemoradiation following curative resection for ampullary adenocarcinoma did not lead to a statistically significant benefit in overall survival. A significant proportion of patients still developed distant metastatic disease suggesting a need for more effective systemic adjuvant therapy.
PLOS ONE | 2014
Nawaz Hack; Sarah M. Fayad; Erin Monari; Umer Akbar; Angela Hardwick; Ramon L. Rodriguez; Irene A. Malaty; Janet Romrell; Aparna Wagle Shukla; Nikolaus R. McFarland; Herbert E. Ward; Michael S. Okun
Background To examine our eight year clinic-based experience in a Parkinson’s disease expert clinical care center using clozapine as a treatment for refractory psychosis in Parkinsons disease (PD). Methods The study was a retrospective chart review which covered eight years of clozapine registry use. Statistical T-tests, chi-square, correlations and regression analysis were used to analyze treatment response for potential associations of age, disease duration, and Hoehn & Yahr (H&Y) score, and degree of response to clozapine therapy. Results There were 36 participants included in the analysis (32 PD, 4 parkinsonism-plus). The characteristics included 30.6% female, age 45–87 years (mean 68.3±10.15), disease duration of 17–240 months (mean 108.14±51.13) and H&Y score of 2 to 4 (mean 2.51±0.51). The overall retention rate on clozapine was 41% and the most common reasons for discontinuation were frequent blood testing (28%), nursing home (NH) placement (11%) and leucopenia (8%). Responses to clozapine across the cohort were: complete (33%), partial (33%), absent (16%), and unknown (16%). Age (r = −0.36, p<0.01) and H&Y score (r = −0.41, p<0.01) were shown to be related to response to clozapine therapy, but disease duration was not an associated factor (r = 0.21, p>0.05). Conclusions This single-center experience highlights the challenges associated with clozapine therapy in PD psychosis. Frequent blood testing remains a significant barrier for clozapine, even in patients with therapeutic benefit. Surprisingly, all patients admitted to a NH discontinued clozapine due to logistical issues of administration and monitoring within that setting. Consideration of the barriers to clozapine therapy will be important to its use and to its continued success in an outpatient setting.
PLOS ONE | 2015
Umer Akbar; Ying He; Yunfeng Dai; Nawaz Hack; Irene A. Malaty; Nikolaus R. McFarland; Christopher W. Hess; Peter J. Schmidt; Samuel S. Wu; Michael S. Okun
Introduction Weight loss is common in Parkinson’s Disease (PD) and sometimes may precede the diagnosis. Weight loss is associated with multiple factors but its impact on health-related quality of life (HRQL) in PD remains unknown. We sought to investigate the factors associated with weight change and to quantify its effect on HRQL. Methods The National Parkinson Foundation Quality Improvement Initiative (NPF-QII) data was used to analyze PD patients longitudinally between two visits, separated by 12±6 months. Multiple linear regression analyses were used to assess the associations between baseline covariates and body weight change per month, and to evaluate whether, and to what degree, Parkinson’s Disease Questionnaire (PDQ-39) scores were affected. Results A higher Hoehn & Yahr stage, higher number of comorbidities, older age, lower MOCA estimate, and higher rate of levodopa usage were observed in patients who lost weight. Multivariate regression analysis indicated that age and levodopa usage were significantly associated with weight loss. Furthermore, monthly body weight loss was significantly associated with HRQL decline in PD patients. Loss of 1 lb (0.45 kg) per month was associated with a decline in QOL: an increase of 0.5% in PDQ-39 Summary Index score (p=0.004), and 1.1% and 1.5% increases in the mobility and ADL dimensions, respectively. Conclusion Weight loss in PD is common and seems to correlate with worsened HRQL. Awareness of factors associated with weight loss and its relation to HRQL may help practitioners improve patient management and expectations.
Frontiers in Neuroscience | 2016
P. Justin Rossi; Aysegul Gunduz; Jack W. Judy; Linda Wilson; Andre G. Machado; James Giordano; W. Jeff Elias; Marvin A. Rossi; Christopher L. Butson; Michael D. Fox; Cameron C. McIntyre; Nader Pouratian; Nicole C. Swann; Coralie de Hemptinne; Robert E. Gross; Howard Jay Chizeck; Michele Tagliati; Andres M. Lozano; Wayne K. Goodman; Jean Philippe Langevin; Ron L. Alterman; Umer Akbar; Greg A. Gerhardt; Warren M. Grill; Mark Hallett; Todd M. Herrington; Jeffrey Herron; Craig van Horne; Brian H. Kopell; Anthony E. Lang
The proceedings of the 3rd Annual Deep Brain Stimulation Think Tank summarize the most contemporary clinical, electrophysiological, imaging, and computational work on DBS for the treatment of neurological and neuropsychiatric disease. Significant innovations of the past year are emphasized. The Think Tanks contributors represent a unique multidisciplinary ensemble of expert neurologists, neurosurgeons, neuropsychologists, psychiatrists, scientists, engineers, and members of industry. Presentations and discussions covered a broad range of topics, including policy and advocacy considerations for the future of DBS, connectomic approaches to DBS targeting, developments in electrophysiology and related strides toward responsive DBS systems, and recent developments in sensor and device technologies.
Parkinsonism & Related Disorders | 2015
Umer Akbar; Bhavpreet Dham; Ying He; Nawaz Hack; Samuel S. Wu; Michelle S. Troche; Patrick J. Tighe; Eugene C. Nelson; Joseph H. Friedman; Michael S. Okun
INTRODUCTION Careful examination of long-term analyses and trends is essential in understanding the medico-economic burden of this common complication. We sought to describe the long-term (32-year) trends of incidence and mortality in PD patients hospitalized with aspiration pneumonia (AsPNA). METHODS Incidence and mortality of AsPNA in hospitalized PD versus non-PD patients was assessed by logistic regression analysis applied to a national database between the years 1979 and 2010. Covariates such as age-decennium, gender, year AsPNA occurred, and the interactions with PD diagnosis were investigated. Rate of AsPNA and mortality over the 32-years was trended and compared. RESULTS AsPNA occurred in 3.6% of PD patients and 1.0% of non-PD patients. The average mortality for PD patients was less (17% vs. 22%). Long-term (32-year) trends revealed a nearly 10-fold increase in incidence of AsPNA in PD (0.4% in 1979, 4.9% in 2010), decreasing mortality overtime, higher likelihood in males, and increasing average age of AsPNA patients (steeper increase in PD). All p-values<0.05. In regression analysis, each successive year had a slight increase in odds of AsPNA (OR 1.03 in PD, OR1.06 in non-PD). CONCLUSIONS Trends over 32 years revealed a 10-fold increase in AsPNA among PD and non-PD patients, and an associated decrease in mortality. Our data suggest that PD patients are living longer, have slightly more AsPNA, but a lower mortality than was seen in past decades. Further research should investigate the causes of AsPNA in PD, and also potential interventions to decrease its occurrence.
Behavioural Brain Research | 2014
Ryan T. Roemmich; Nawaz Hack; Umer Akbar; Chris J. Hass
Persons with Parkinsons disease (PD) are characterized by multifactorial gait deficits, though the factors which influence the abilities of persons with PD to adapt and store new gait patterns are unclear. The purpose of this study was to investigate the effects of dopaminergic therapy on the abilities of persons with PD to adapt and store gait parameters during split-belt treadmill (SBT) walking. Ten participants with idiopathic PD who were being treated with stable doses of orally-administered dopaminergic therapy participated. All participants performed two randomized testing sessions on separate days: once while optimally-medicated (ON meds) and once after 12-h withdrawal from dopaminergic medication (OFF meds). During each session, locomotor adaptation was investigated as the participants walked on a SBT for 10 min while the belts moved at a 2:1 speed ratio. We assessed locomotor adaptive learning by quantifying: (1) aftereffects during de-adaptation (once the belts returned to tied speeds immediately following SBT walking) and (2) savings during re-adaptation (as the participants repeated the same SBT walking task after washout of aftereffects following the initial SBT task). The withholding of dopaminergic medication diminished step length aftereffects significantly during de-adaptation. However, both locomotor adaptation and savings were unaffected by levodopa. These findings suggest that dopaminergic pathways influence aftereffect storage but do not influence locomotor adaptation or savings within a single session of SBT walking. It appears important that persons with PD should be optimally-medicated if walking on the SBT as gait rehabilitation.
American Journal of Neuroradiology | 2013
Ameer E. Hassan; Umer Akbar; Saqib A Chaudhry; W.G. Tekle; Ramachandra P. Tummala; Gustavo J. Rodriguez; Adnan I. Qureshi
The purpose of this investigation was to determine the number of patients undergoing endovascular procedures under conscious sedation in whom general anesthesia and intubation were ultimately required. Of 520 subjects treated under conscious sedation, 9 (1.7%) required emergent intubation. This intubation had no effect on clinical outcome or in-hospital mortality. BACKGROUND AND PURPOSE: Neuroendovascular procedures are performed with the patient under conscious sedation (local anesthesia) in varying numbers of patients in different institutions, though the risk of unplanned conversion to general anesthesia is poorly characterized. Our aim was to ascertain the rate of failure of conscious sedation in patients undergoing neuroendovascular procedures and compare the in-hospital outcomes of patients who were converted from conscious sedation to general anesthesia with those whose procedures were initiated with general anesthesia. MATERIALS AND METHODS: All patients who had an endovascular procedure initiated under general anesthesia or conscious sedation were identified through a prospective data base maintained at 2 comprehensive stroke centers. Patient clinical and procedural characteristics, in-hospital deaths, and favorable outcomes (modified Rankin Scale score, 0–2) at discharge were ascertained. RESULTS: Nine hundred seven endovascular procedures were identified, of which 387 were performed with the patient under general anesthesia, while 520 procedures were initiated with conscious sedation. Among procedures initiated with intent to be performed under conscious sedation, 9 (1.7%) procedures required emergent conversion to general anesthesia. Favorable clinical outcome and in-hospital mortality in patients requiring emergent conversion from conscious sedation to general anesthesia and in those with procedures initiated with general anesthesia were not statistically different (42% versus 50%, P = .73 and 17% versus 13%, P = 1.00, respectively). CONCLUSIONS: In our study, there was a very low rate of conscious sedation failure and associated adverse outcomes among patients undergoing neuroendovascular procedures. Proper patient selection is important if procedures are to be performed with the patient under conscious sedation. Limitations of the methodology used in our study preclude us from offering specific recommendations regarding when to use a specific anesthetic protocol.
Neuromodulation | 2016
Umer Akbar; Robert S. Raike; Nawaz Hack; Christopher W. Hess; Jared W. Skinner; Daniel Martinez-Ramirez; Sol DeJesus; Michael S. Okun
Evidence suggests that nonconventional programming may improve deep brain stimulation (DBS) therapy for movement disorders. The primary objective was to assess feasibility of testing the tolerability of several nonconventional settings in Parkinsons disease (PD) and essential tremor (ET) subjects in a single office visit. Secondary objectives were to explore for potential efficacy signals and to assess the energy demand on the implantable pulse‐generators (IPGs).
Frontiers in Integrative Neuroscience | 2016
Wissam Deeb; James Giordano; Peter J. Rossi; Alon Y. Mogilner; Aysegul Gunduz; Jack W. Judy; Bryan T. Klassen; Christopher R. Butson; Craig van Horne; Damiaan Deny; Darin D. Dougherty; David Rowell; Greg A. Gerhardt; Gwenn S. Smith; Francisco A. Ponce; Harrison C. Walker; Helen Bronte-Stewart; Helen S. Mayberg; Howard Jay Chizeck; Jean Philippe Langevin; Jens Volkmann; Jill L. Ostrem; Jonathan Shute; Joohi Jimenez-Shahed; Kelly D. Foote; Aparna Wagle Shukla; Marvin A. Rossi; Michael Oh; Michael Pourfar; Paul B. Rosenberg
This paper provides an overview of current progress in the technological advances and the use of deep brain stimulation (DBS) to treat neurological and neuropsychiatric disorders, as presented by participants of the Fourth Annual DBS Think Tank, which was convened in March 2016 in conjunction with the Center for Movement Disorders and Neurorestoration at the University of Florida, Gainesveille FL, USA. The Think Tank discussions first focused on policy and advocacy in DBS research and clinical practice, formation of registries, and issues involving the use of DBS in the treatment of Tourette Syndrome. Next, advances in the use of neuroimaging and electrochemical markers to enhance DBS specificity were addressed. Updates on ongoing use and developments of DBS for the treatment of Parkinsons disease, essential tremor, Alzheimers disease, depression, post-traumatic stress disorder, obesity, addiction were presented, and progress toward innovation(s) in closed-loop applications were discussed. Each section of these proceedings provides updates and highlights of new information as presented at this years international Think Tank, with a view toward current and near future advancement of the field.
Journal of Critical Care | 2011
Fred Rincon; Tricia Morino; Danielle Behrens; Umer Akbar; Christa Schorr; Elizabeth Lee; David R. Gerber; Joseph E. Parrillo; Thomas Mirsen
INTRODUCTION Transfer of critically ill patients from outside emergency department has the potential for delaying the admission to the intensive care unit. We sought to determine the effect of outside emergency department transfer on hospital outcomes in critically ill patients with stroke. METHODS We designed a retrospective cohort analysis using a prospectively compiled and maintained registry (Cerner Project IMPACT). Patients with acute ischemic stroke and intracerebral hemorrhage admitted to our intensive care unit from our emergency department and transfers from outside emergency department within 24 hours of stroke between January 1, 2003, and December 31, 2008, were selected for the analysis. Data collected included demographics, admission physiologic variables, Glasgow Coma Scale, Acute Physiology and Chronic Health Evaluation II score, and total intensive care unit and hospital length of stay. Primary (poor) outcome was a composite of death or fully dependent status at hospital discharge, and secondary outcomes were intensive care unit and hospital length of stay. To assess for the impact of outside emergency department transfer on primary and secondary outcomes, demographic and admission clinical variables were used to construct logistic regression models using the outcome measure as a dependent variable. RESULTS A total of 448 patients were selected for analysis. The mean age was 65 ± 14 years, of which 214 (48%) were male and 282 (65%) white, 152 (34%) were patients with acute ischemic stroke, and 296 (66%) were patients with intracerebral hemorrhage. The median hospital length of stay was 7 days (interquartile range, 4-11 days) and median intensive care unit length of stay was 2 days (interquartile range, 1-3 days). Overall hospital mortality was 30%, and outside emergency department transfer increased the odds of poor outcome by 2-fold (65% vs 34%; P = .05). Multivariate regression analysis showed that age (odds ratio [OR], 1.02; 95% confidence interval [CI], 1.01-1.1), Acute Physiology and Chronic Health Evaluation II score >14 (OR, 1.9; 95% CI, 1.3-2.7), Glasgow Coma Scale <12 (OR, 2.0; 95% CI, 1.4-2.8), do-not-resuscitate status (OR, 3.5; 95% CI, 2.2-5.9), and outside emergency department transfers (OR, 1.4; 95% CI, 1.02-1.8) were independently associated with poor outcome. Outside emergency department transfer was not significantly associated with secondary outcomes. CONCLUSION These data suggest that in critically ill patients with stroke, transfer from outside emergency department is independently associated with poor outcome at hospital discharge. Further research is needed as to identify the potential causes for this effect.