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Improving Compliance via Education, Reminders, and Evaluating Physician-Patient Concerns in Glaucoma
Get PDFPURPOSE: To improve glaucoma treatment compliance via education, medication reminders, and understanding of patient and physician concerns.
DESIGN: Prospective Comparative Case Series
SUBJECTS: 194 consecutive eligible patients diagnosed with primary open angle glaucoma or ocular hypertension at a single academic center (92 male and 102 female) and 16 glaucoma specialists volunteered their responses.
METHODS: All 194 eligible patients were interviewed regarding glaucoma knowledge, medication usage, concerns, and fears. They were counseled, given educational handouts, and reinterviewed after 4 weeks. All 16 glaucoma specialists were also surveyed regarding their concerns for their patients.
MAIN OUTCOME MEASURE: Patient's knowledge of the basic premise of glaucoma, compliance to their medications, including concerns and fears of glaucoma in both patients and physicians.
RESULTS: In this study, patients aged ≥ 65 years were more compliant than those < 65 years (76% vs 50%, p<0.05). In follow-up interviews of 125 (64%) patients, I found significant increase in glaucoma knowledge from 53% to 67% (p<0.05) and compliance from 77% to 94% (p<0.05). In addition, patients' major fear was becoming dependent on others (p<0.05), while physicians were more concerned about patients' ability to administer eyedrops and understanding of instructions (p<0.05).
CONCLUSION: I found that patients aged ≥ 65 were more compliant. Our intervention improved patient compliance by 17 % and represents a potential model for glaucoma management. In addition, the disparity between patient and physician fears suggest that communication barriers must be addressed to improve patient care
Bury Me on a Rainy Day
No full textThe author submitted this entry in the Open Verse Poetry category (Amateur division) for the 2024 On My Own Time (OMOT) Art Show.A friend shared the news of a loved one's passing while I was back home visiting family. I received the news via text in the sunroom of my sister's house. It was a quiet, gray afternoon, with a light mist covering the fields behind their east Texas home. While reflecting on the loss, I imagined the additional stress of laying someone to rest on an afternoon of bad weather. And yet I found my mind drifting towards the deceased's perspective, and how perhaps he would see the beauty in being memorialized on a rainy day. And as he slowly transitioned from the physical world, he would latch on to the weather, succumbing to sentimentality, listening to the sound of thunder and rain one last time
Decisional Regret: Investigating the Patient Experience with Shared Decision Making as a Public Health Concern
No full textThe general metadata -- e.g., title, author, abstract, subject headings, etc. -- is publicly available, but access to the submitted files is restricted to UT Southwestern campus access and/or authorized UT Southwestern users.The content of this work is based on the previously published articles that are cited below. The author has permission from the publisher to use the works listed below within the thesis.BACKGROUND: Among older adults (> 65 years old), adult spinal deformity (ASD) is a leading cause of disability, with a population prevalence of 60%-70%. Surgical referral for deformity correction is common despite the high rates of postoperative complications. Because surgery involves trade-offs between clear benefits and risks, the patient's perspective is essential in deciding whether or not to undergo surgery.
LOCAL PROBLEM: The UT Southwestern Spine Center takes a multidisciplinary approach to the care of older patients through the implementation of the POSH (Perioperative Optimization of Senior Health) Program. This study will determine the prevalence of decisional regret in patients who have undergone spine surgery for symptomatic degenerative scoliosis and identify the root causes that may contribute to high decisional regret in these patients.
METHODS: Older adults with a diagnosis of ASD who underwent spinal surgery at a quaternary medical center from January 2016 to March 2019, were enrolled in this study. Patients were categorized into medium/high or low-decisional regret cohorts based on their responses to the Ottawa decision regret questionnaire. Decisional regret assessments were completed 24 months after surgery.
Using purposeful sampling we identified older adult patients who underwent deformity correction surgery between the aforementioned time period. We conducted semi-structured, in-depth interviews with six patients (average age 73 years old, 83% women, all white) and five spine surgeons (years in practice 3 - 11). Two investigators independently coded the transcripts using constant comparative method, as well as an integrative, team-based approach to identify themes.
RESULTS: Four themes emerged from interviews with patients: (1) patients felt surgery was their only choice because they were running out of time to undergo invasive procedures; (2) patients mentally committed to surgery prior to the initial encounter with their surgeon and contextualized the desired benefits while minimizing the potential risks; (3) patients felt that the current decision support tools were ineffective in preparing them for surgery; and (4) patients felt that pain management was the most difficult part of recovery from surgery which wasn't discussed comprehensively by their surgeon/care team prior to surgery. Four themes emerged from interviews with surgeons: (1) although spine surgeons intuitively understood the concept of shared decision making, they varied substantially in their interpretations; (2) spine surgeons did not consider patients' chronological age as a major contraindication to undergoing surgery; (3) there is a goal mismatch between patients and surgeons in the desired outcomes from surgery, where patients prioritize complete pain relief whereas surgeons prioritize concrete functional improvement; and (4) spine surgeons felt that patient expectations from surgery were often established prior to their initial surgery visit, and frequently required recalibration.
CONCLUSION: While the majority of older adults were appropriately counselled and satisfied with their decision, one-in-five older adults regret their decision to undergo surgery. Older adult patients viewed the decision to have surgery as time-sensitive, whereas spine surgeons expressed the need for recalibrating patient expectations and balancing the risks and benefits when considering surgery for older adults with symptomatic spinal deformity. These findings highlight the need for improved understanding of both sides of shared decision making which should involve the needs and priorities of older adults to help convey patient-specific risks and choice awareness
Technical Development of Hyperpolarized [1-13C]Pyruvate Imaging for Clinical Translation
Get PDFMagnetic resonance imaging with hyperpolarized [1-13C]pyruvate is an emerging tool for assessing in vivo metabolism noninvasively. Over the past few years since the first clinical study with prostate cancer patients, translational studies using this imaging technique have been focused on demonstrating the feasibility of applying to healthy subjects and patients under several pathophysiological conditions. However, there are multiple remaining technical limitations to overcome for translating the technique to clinics. In this study, I made three technical advances in imaging hyperpolarized [1-13C]pyruvate and products in humans.
First, I measured in vivo T2* of hyperpolarized signals, one of the key parameters that directly affect 13C acquisition methods and image quality. Measuring the in vivo T2*'s can be useful for optimizing the acquisition parameters and improving the signal-to-noise ratio. I proposed a dynamic 13C metabolite-selective multi-echo spiral imaging sequence for the T2* measurement of hyperpolarized 13C-labeled metabolites. The feasibility and reproducibility of the method were confirmed by phantom and rat studies. Moreover, from healthy volunteers, in vivo T2*s of hyperpolarized [1-13C]pyruvate, [1-13C]lactate and [13C]bicarbonate were measured from cardiac tissue compartments using the sequence.
Second, I developed a cardiac-gated multi-phase 13C imaging sequence for the human heart. To demonstrate cyclic changes in cardiac metabolic profiles seen by hyperpolarized signals, dual-phase cardiac imaging of hyperpolarized [1-13C]pyruvate, [1-13C]lactate, [1-13C]alanine and [13C]bicarbonate was conducted at end-systole (ES) and end-diastole (ED) on the short-axis and vertical long-axis planes. Significantly smaller myocardial signal of [13C]bicarbonate relative to [1-13C]lactate was observed at ED compared to that at ES (p < 0.05).
Third, a patch-based algorithm (PA) was developed to improve spatial resolution of hyperpolarized 13C images by exploiting the co-registered high-resolution 1H images. The spatial resolution of hyperpolarized 13C imaging is genuinely poor, compromising the overall image conspicuity and limiting accurate assessment of the hyperpolarized 13C metabolites. The PA was validated in simulation and phantom studies, and was further applied to low-resolution human brain metabolite maps of hyperpolarized [1-13C]pyruvate and [1-13C]lactate with three compartment segmentation (grey matter, white matter and cerebrospinal fluid). The results demonstrated that the PA can enhance low-resolution hyperpolarized 13C images in terms of spatial resolution and contrast while preserving quantification accuracy and intra-compartment signal inhomogeneity
Cooperativity: Physiologic Cornerstone and Emerging Therapeutic Design Principle
No full textThe content of this work is based on the previously published articles that are cited below.Precise spatiotemporal control of molecular transport is vital to functional physiological systems. Nature evolved to apply macromolecular cooperativity to achieve precision over systemic delivery of important molecules. In drug delivery, conventional nanocarriers employ inert materials and rely on passive accumulation for tissue targeting and diffusion for drug release. Early clinical studies show these nanodrugs have not delivered the anticipated impact on therapy. Inspired by nature, this dissertation explores a design principle that incorporates nanoscale cooperativity and phase transition to sense and amplify physiological signals to improve the therapeutic outcome. Using ultra-pH-sensitive (UPS) nanoparticles as an example, I will first demonstrate how all-or-nothing protonation cooperativity during micelle assembly/disassembly can be exploited to increase dose accumulation and achieve rapid drug release in acidic microenvironments. In ongoing development, I will then present three facets of investigation into a UPS-based nanovaccine platform using the polymer PC7A for cancer immunotherapy. The first line of inquiry involves a systematic investigation of physicochemical properties of the nanovaccine with a detailed characterization of the biophysical relationship between PC7A nanoparticles and peptide-based antigens. This work identifies dual-cooperative phase transition of the micelle and peptide, both of which are necessary for downstream vaccine efficacy. The second line of inquiry comprises the development of a biodegradable series of UPS nanoparticles. This work culminates with the investigation of a biodegradable nanovaccine and its improved safety profiles compared with the nondegradable predecessor. Finally, the third line of inquiry explores the roles of myeloid cells in governing the T cell responses following vaccination by PC7A and subsequent therapeutic resistance. This work identifies a population of macrophages which interacts with and suppresses T cell activity, leading to therapeutic resistance, and culminates with the development of combinatorial therapies to overcome resistance. Together, these bodies of work cooperate to enable optimized nanoparticle vaccination strategies through the improvement of biophysical stability, physiologic safety profiles, and long-term efficacy in late-stage tumors
Reducing Patient No-Show Rates in Diabetes Clinic
Get PDFBACKGROUND: Patients missing scheduled appointments, or no-shows, is a pervasive issue across outpatient clinics. The estimated no-show rate among primary care clinics is estimated to be between 14% and 50% (Daggy, Lawley et al. 2010). In addition, no-shows are estimated to cost the US healthcare system $150 billion a year (Toland 2013). At many clinics no-shows have necessitated overbooking clinic slots to maintain efficiency (Muthuraman and Lawley 2008). However, patient no-shows themselves and the overbooking that no-shows necessitate causes problems for both the patient and provider.
LOCAL PROBLEM: No-show rates have a number of adverse effects on the clinic, including at the Parkland Diabetes Clinic in Dallas, TX. This leads to longer wait times when all patients show, patient/provider/staff stress and frustration, and reduced clinical efficiency. No-shows and late cancellations can also lead to reduced patient access to care and potential increase in disease progression risk for those patients who fail to receive follow-up care.
METHODS: This project used the PDSA cycle from quality improvement methodology. We started by analyzing the current situation at the diabetes clinic to determine the baseline no-show rate and the reasons for patient no-shows. Baseline data on no-shows were provided by Dr. Gunasekaran and Miriam Gomez-Wakeling; data was analyzed by Farzan Jafri. The scheduling process was mapped in an effort to identify inefficiencies in the scheduling process. Phone calls were then conducted with patients who no-showed in which a survey helped pinpoint reasons for no-shows. Using the process map and survey data, we brainstormed interventions to target root causes of no-shows at the clinic.
PLANNED OR ACTUAL INTERVENTIONS: Our first intervention is ensuring that every patient receives a phone call reminder for their appointment. Our second intervention is limiting the degree to which the Patient Access Center, a call center, handles scheduling for the Diabetes clinic.
RESULTS: Interventions were implemented in August 2020, and subsequent data collected from November 2020 to October 2021 was analyzed to determine changes in the no-show rate. The average no-show rate during this post-intervention period was ~22.2% ± 2.50 (t-test, p <0.05), a significant decrease from the baseline rate of ~31.9% ± 2.19. We predict this reduction will result in more consistent follow-up care, less risk of disease progression, and increased clinical efficiency. Our next step will be to transition our interventions into long-term sustainable solutions to maintain the lower no-show rate.
CONCLUSIONS: Our project demonstrates that by following quality improvement methodology and the PDSA cycle, root causes for system inefficiencies can be targeted with site specific interventions. With support from leadership and buy-in from staff, these interventions can go on to positively impact the main problem being studied, or in our case the high no-show rate at the Parkland Diabetes clinic. While our specific interventions may not apply to every clinical context, the methods employed in this study can certainly be reproduced to target high no-show rates at other outpatient centers
Updates in management of atrial fibrillation in systolic heart failure
Get PDFDetailed formal protocol with illustrations and extensive bibliography.A recording of the protocol presentation is available on UT Southwestern's Mediasite. Note: Access to the video is restricted to authorized UT Southwestern users only.UT Southwestern--Internal Medicin
Hush Money
Get PDFThe author submitted this entry in the Fictional Short Story category (Amateur division) for the 2024 On My Own Time (OMOT) Art Show.This work received a Second Place Award in the "Fictional Short Story" category in the 2024 On My Own Time show.I was inspired by a series of questions my children asked me as they started to become aware of mortality. I tried to soften the whole concept of life and death when surprisingly all they wanted was a straightforward answer
Investigating Vascular Patterning and Regression in Kidney Development and Organoids
Get PDFPages 74-127 are misnumbered as pages 75-128.Chronic kidney disease (CKD) and end stage renal disease (ESRD) are increasingly frequent and devastating conditions that have driven a surge in the need for kidney transplantation. A stark shortage of organs has fueled interest in generating viable replacement tissues ex vivo for transplantation. One promising approach has been self-organizing organoids, which mimic developmental processes and yield multicellular, organ-specific tissues. However, a recognized roadblock to this approach is that many organoid cell types fail to acquire full maturity and function. I comprehensively assessed the vasculature in two distinct kidney organoid models as well as in explanted embryonic kidneys. Using a variety of methods, my work shows that while organoids can develop a wide range of kidney cell types, as previously shown, endothelial cells (ECs) initially arise but then rapidly regress overtime in culture. Vasculature of cultured embryonic kidneys exhibit similar regression. By contrast, engraftment of kidney organoids under the kidney capsule results in the formation of a stable, perfused vasculature that integrates into the organoid. This work demonstrates that kidney organoids offer a promising model system to define the complexities of vascular-nephron interactions, but the establishment and maintenance of a vascular network present unique challenges when grown ex vivo. The future of the field necessitates the inclusion of flow and perhaps additional factors into in vitro culture methods. Future studies investigating endothelial heterogeneity in the developing kidney will aid in forwarding our mission of creating a functional organoid vasculature
The Structural Distribution of Epistasis in a Pair of Essential Metabolic Enzymes
Get PDFInteractions between proteins provide the basis for cells to perform metabolism, grow, divide, move, and appropriately respond to external stimuli. Because proteins do not act as independent entities, the genetic background influences the effect of a mutation in unexpected ways. This context-dependence of mutational effects is epistasis. Extensive progress has been made in our ability to identify epistasis between proteins. However, how the epistasis between a pair of proteins is distributed across the amino acid sequence is less clear. Previous work characterized this sequence-level epistasis between proteins that bind to form a physical complex. Until now, the structural pattern and magnitude of epistasis between pairs of mutations spanning interacting metabolic enzymes remained uncharacterized.
In my dissertation work, I deeply examined the context dependence of mutations for two essential enzymes in the bacterial folate metabolic pathway, Dihydrofolate Reductase (DHFR) and Thymidylate Synthase (TYMS). To achieve this goal, I used deep mutational scanning assays on DHFR in the context of varying activities of TYMS. The result is a rigorous dataset with epistasis measurements over the entire amino acid sequence of DHFR. I found that the positions with the greatest magnitude of epistasis within the structure of DHFR lied at the active site. However, the sign of epistasis at the DHFR active site was dependent on whether TYMS was active. Beyond the active site, the distribution of positive epistasis among the positions of DHFR was also context- dependent on the state of TYMS. Therefore, we can think of the active site as a non-physical "interface" between protein pairs that do not form a physical complex but share an intermediate.
The potential consequences of this dataset on the epistasis between DHFR and TYMS are profound. This dataset is fundamental towards our understanding of how epistasis mechanistically emerges in nonlinearities between catalytic activity in enzymes, protein abundance, and cellular growth rate. This experimental dataset is also necessary to credibly validate predictions of epistasis from models of statistical co-evolution