YOUNGRAN, KIMALSHAIKH, ABDULAZIZ2025-07-162025-04-14https://hdl.handle.net/20.500.14154/75868This dissertation investigates the utilization of follow-up appointment modalities, specifically in-person and telemedicine visits, and the factors influencing their adoption among patients discharged from emergency departments (ED) for uncontrolled hypertension in the United States between 2021 and 2022. The study aims to assess the prevalence of follow-up modalities, evaluate the time intervals to follow-up by modality, and identify demographic and clinical predictors of telemedicine adoption. To achieve these objectives, a retrospective observational cohort study was conducted using Merative MarketScan Commercial Claims data, analyzing 28,425 patients, categorized into three groups: in-person follow-up, telemedicine follow-up, or no follow-up. Among the study population, 30.5% of patients had no follow-up visit, while 64.8% received in-person follow-up, and 4.7% had follow-up via telemedicine. Subgroup analyses revealed significant differences in follow-up appointment status across demographic and clinical characteristics. Older patients were significantly more likely vii to have a follow-up visit compared to younger patients. Specifically, patients aged 55–64 had a 12% higher likelihood of follow-up compared to those aged 18–34 (aPR = 1.12; 95% CI: 1.08–1.16; p < 0.001). Patients aged 45–54 had an 8% higher likelihood (aPR = 1.08; 95% CI: 1.04–1.11; p < 0.001), and those aged 35–44 had a 4% higher likelihood (aPR = 1.04; 95% CI: 1.01–1.08; p = 0.019). Female patients were 6% more likely to receive follow-up than males (aPR = 1.06; 95% CI: 1.05–1.08; p < 0.001). Geographic differences were also observed. Patients in the South had an 8% lower likelihood of follow-up compared to those in the Northeast (aPR = 0.92; 95% CI: 0.90–0.94; p < 0.001), and those in the West had a 5% lower likelihood (aPR = 0.95; 95% CI: 0.92 0.98; p = 0.001). Patients with prior hypertension medication use were 6% more likely to receive follow-up compared to those without such history (aPR = 1.06; 95% CI: 1.05–1.08; p < 0.001). Increasing comorbidity burden was also associated with higher follow-up rates: patients with a CCI score of 1 had a 4% higher likelihood (aPR = 1.04; 95% CI: 1.02–1.06; p < 0.001), those with a score of 2 had a 7% higher likelihood (aPR = 1.07; 95% CI: 1.04–1.11; p < 0.001), and those with a score of 3 or more had a 13% higher likelihood of follow-up compared to patients with a CCI score of 0 (aPR = 1.13; 95% CI: 1.10–1.17; p < 0.001). Among the 19,762 patients who received follow-up care, 93.2% were seen in person, while 6.8% had a telemedicine visit. Subgroup analyses revealed significant differences in telemedicine utilization among these patients. Compared to patients aged 18–34, those aged 45–54 was 19% less likely (aPR = 0.81; 95% CI: 0.67–0.98; p = 0.034), and those aged 55 64 were 27% less likely to use telemedicine (aPR = 0.73; 95% CI: 0.60–0.89; p = 0.001). Female patients were 22% more likely than males to use telemedicine (aPR = 1.22; 95% CI: viii 1.10–1.36; p < 0.001). Regionally, patients in the West were 57% more likely to use telemedicine compared to those in the Northeast (aPR = 1.57; 95% CI: 1.31–1.89; p < 0.001), while patients in the South and North Central were 27% and 25% less likely, respectively (aPR = 0.73 and 0.75). Patients with prior hypertension medication use were 19% more likely to use telemedicine (aPR = 1.19; 95% CI: 1.07–1.33; p = 0.001), and those with a CCI score of 1 were 21% more likely compared to patients with no comorbidities (aPR = 1.21; 95% CI: 1.06–1.37; p = 0.004). The timing of follow-up care was analyzed among 19,762 patients who had a recorded follow-up visit. Kaplan-Meier survival analysis showed no statistically significant difference in the timing of follow-up between telemedicine and in-person visits (p = 0.6902). The Cox proportional hazards regression model, adjusting for age, sex, region, medication use, and comorbidities, confirmed no significant difference in follow-up timing between the two modalities (HR = 1.01, p = 0.611). These findings reveal meaningful differences in post-ED follow-up care among patients with uncontrolled hypertension, highlighting demographic, clinical, and regional variations in telemedicine use. Telemedicine follow-up was more likely among younger adults, females, and patients residing in the West, while patients aged 45 and older, males, and individuals in the South and North Central regions were significantly less likely to use telemedicine. Additionally, patients with prior hypertension medication use and those with mild comorbidity burden were more likely to engage in telemedicine follow-up. The absence of significant differences in follow-up timing between telemedicine and in-person visits supports the feasibility of virtual care as a timely alternative to traditional follow-up. These ix differences in telemedicine utilization underscore the need for targeted interventions to expand equitable access, particularly for older adults, men, and populations in regions with lower adoption rates. This research provides evidence-based insights to inform policymakers, healthcare providers, and insurers on factors influencing post-ED follow-up care. These findings can contribute to optimizing telemedicine implementation, reducing differences in access, and enhancing continuity of care for patients with hypertension, ultimately supporting more effective and equitable healthcare delivery strategies.Hypertension remains a leading public health concern, contributing to a significant burden of emergency department (ED) visits, particularly when blood pressure is poorly controlled. Patients who visit the ED for uncontrolled hypertension often require timely follow-up care to prevent recurrent ED visits, hospitalizations, and long-term complications. However, gaps in continuity of care post-ED discharge persist, with a substantial proportion of patients failing to receive appropriate outpatient follow-up. The COVID-19 pandemic accelerated the adoption of telemedicine, offering an alternative modality for post-ED follow-up care. Despite the increased availability of virtual care, the extent to which telemedicine is utilized for follow-up after an ED visit for uncontrolled hypertension remains unclear. Moreover, there is limited research comparing the timing of telemedicine versus in-person follow-up or identifying the factors associated with the selection of follow-up modality. This research aims to address these gaps by examining the prevalence of telemedicine versus in-person follow-up visits after an ED visit for uncontrolled hypertension, assessing the time interval between ED discharge and follow-up care by modality, and determining the demographic and clinical characteristics influencing follow-up modality selection. By leveraging U.S. commercial insurance claims data from 2021–2022, this study provides real world insights into the use of telemedicine in hypertension management, informing future strategies to enhance continuity of care, and reduce healthcare differences. v69en-UShypertension TelehealthThesis