Browsing by Subject "Observational study"

Now showing 1 - 6 of 6
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    Effect of diabetes on caregiver burden in an observational study of individuals with Alzheimer's disease
    (BioMed Central, 2016-05-03) Lebrec, Jeremie; Ascher-Svanum, Haya; Chen, Yun-Fei; Reed, Catherine; Kahle-Wrobleski, Kristin; Hake, Ann Marie; Raskin, Joel; Naderali, Ebrahim; Schuster, Dara; Heine, Robert J.; Kendall, David M.; Department of Neurology, IU School of Medicine
    BACKGROUND: The burden on caregivers of patients with Alzheimer's disease (AD) is associated with the patient's functional status and may also be influenced by chronic comorbid medical conditions, such as diabetes. This post-hoc exploratory analysis assessed whether comorbid diabetes in patients with AD affects caregiver burden, and whether caregivers with diabetes experience greater burden than caregivers without diabetes. Caregiver and patient healthcare resource use (HCRU) were also assessed. METHODS: Baseline data from the GERAS observational study of patients with AD and their caregivers (both n = 1495) in France, Germany and the UK were analyzed. Caregiver burden was assessed using the Zarit Burden Interview (ZBI). Caregiver time on activities of daily living (ADL: basic ADL; instrumental ADL, iADL) and supervision (hours/month), and caregiver and patient HCRU (outpatient visits, emergency room visits, nights hospitalized) were assessed using the Resource Utilization in Dementia instrument for the month before the baseline visit. Regression analyses were adjusted for relevant covariates. Time on supervision and basic ADL was analyzed using zero-inflated negative binomial regression. RESULTS: Caregivers of patients with diabetes (n = 188) were younger and more likely to be female (both p < 0.05), compared with caregivers of patients without diabetes (n = 1307). Analyses showed caregivers of patients with diabetes spent significantly more time on iADL (+16 %; p = 0.03; increases were also observed for basic ADL and total caregiver time but did not reach statistical significance) and had a trend towards increased ZBI score. Patients with diabetes had a 63 % increase in the odds of requiring supervision versus those without diabetes (p = 0.01). Caregiver and patient HCRU did not differ according to patient diabetes. Caregivers with diabetes (n = 127) did not differ from those without diabetes (n = 1367) regarding burden/time, but caregivers with diabetes had a 91 % increase in the odds of having outpatient visits (p = 0.01). CONCLUSIONS: This cross-sectional analysis found caregiver time on iADL and supervision was higher for caregivers of patients with AD and diabetes versus without diabetes, while HCRU was unaffected by patient diabetes. Longitudinal analyses assessing change in caregiver burden over time by patient diabetes status may help clarify the cumulative impact of diabetes and AD dementia on caregiver burden.
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    Mild Cognitive Impairment as an Early Landmark in Huntington's Disease
    (Frontiers Media, 2021-07-07) Zhang, Ying; Zhou, Junyi; Gehl, Carissa R.; Long, Jeffrey D.; Johnson, Hans; Magnotta, Vincent A.; Sewell, Daniel; Shannon, Kathleen; Paulsen, Jane S.; Biostatistics and Health Data Science, Richard M. Fairbanks School of Public Health
    As one of the clinical triad in Huntington's disease (HD), cognitive impairment has not been widely accepted as a disease stage indicator in HD literature. This work aims to study cognitive impairment thoroughly for prodromal HD individuals with the data from a 12-year observational study to determine whether Mild Cognitive Impairment (MCI) in HD gene-mutation carriers is a defensible indicator of early disease. Prodromal HD gene-mutation carriers evaluated annually at one of 32 worldwide sites from September 2002 to April 2014 were evaluated for MCI in six cognitive domains. Linear mixed-effects models were used to determine age-, education-, and retest-adjusted cut-off values in cognitive assessment for MCI, and then the concurrent and predictive validity of MCI was assessed. Accelerated failure time (AFT) models were used to determine the timing of MCI (single-, two-, and multiple-domain), and dementia, which was defined as MCI plus functional loss. Seven hundred and sixty-eight prodromal HD participants had completed all six cognitive tasks, had MRI, and underwent longitudinal assessments. Over half (i.e., 54%) of the participants had MCI at study entry, and half of these had single-domain MCI. Compared to participants with intact cognitive performances, prodromal HD with MCI had higher genetic burden, worsened motor impairment, greater brain atrophy, and a higher likelihood of estimated HD onset. Prospective longitudinal study of those without MCI at baseline showed that 48% had MCI in subsequent visits and data visualization suggested that single-domain MCI, two-domain MCI, and dementia represent appropriate cognitive impairment staging for HD gene-mutation carriers. Findings suggest that MCI represents an early landmark of HD and may be a sensitive enrichment variable or endpoint for prodromal clinical trials of disease modifying therapeutics.
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    New statistical methods for the evaluation of effectivenss and safety of a medical intervention in using observational data
    (2016-12-05) Zhan, Jia; Shen, Changyu; Li, Xiaochun; Li, Lingling; Xu, Huiping; Wessel, Jennifer
    Observational studies offer unique advantages over randomized clinical trials (RCTs) in many situations where RCTs are not feasible or suffer from major limitations such as insufficient sample sizes and narrowly focused populations. Because observational data are relatively easy and inexpensive to access, and contain rich and comprehensive demographic and medical information on large and representative populations, they have played a major role in the assessment of the effectiveness and safety of medical interventions. However, observational data also have the challenges of higher rates of missing data and the confounding effect. My proposal is on the development of three statistical methods to address these challenges. The first method is on the refinement and extension of a multiply robust (MR) estimation procedure that simultaneously accounts for the confounding effect and missing covariate process, where we derived the asymptotic variance estimator and extended the method to the scenario where the missing covariate is continuous. The second method focuses on the improvement of estimation precision in an RCT by a historical control cohort. This was achieved through augmenting the conventional effect estimator with an extra mean zero (approximately) term correlated with the conventional effect estimator. In the third method, we calibrated the hidden database bias of an electronic medical records database and utilized an empirical Bayes method to improve the accuracy of the estimation of the risk of acute myocardial infarction associated with a drug by borrowing information from other drugs.
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    Rapid implementation of Veterans Health Administration telehealth creative arts therapies: survey evaluation of adoption and adaptation
    (BMC, 2023-07-19) Story, Kristin M.; Flanagan, Mindy E.; Robb, Sheri L.; Bravata, Dawn M.; Bair, Matthew J.; Otto, David; Damush, Teresa M.; School of Nursing
    Background: Creative arts therapies (CAT) are employed throughout the Veterans Health Administration (VHA) and are predominantly delivered in-person. Though telehealth delivery of CAT was used at several VHA facilities to increase services to rural Veterans, due to guidance from the Center for Disease Control and VHA that temporarily suspended or reduced in-person services, there was a large increase of CAT therapists enterprise-wide who adopted telehealth delivery. The aims of this study were to evaluate adoption and adaptation of CAT telehealth delivery and identify related barriers and facilitators. Methods: We deployed a survey guided by the Consolidated Framework for Implementation Research and administered it via email to all VHA CAT therapists (N = 120). Descriptive statistics were used to summarize data and responses were compared based on therapists' age, years of experience and CAT discipline. Open survey field responses were summarized, qualitatively coded, and analyzed thematically. Results: Most therapists (76%) reported adopting telehealth with 74% each delivering > 50 CAT sessions in the prior year. Therapists adapted interventions or created new ones to be delivered through telehealth. Barriers included: technical challenges, control of the virtual space, and building rapport. Facilitators included added equipment, software, and infrastructure. CAT therapists adapted their session preparation, session content, outcome expectations, and equipment. CAT therapists reported being able to reach more patients and improved access to care with telehealth compared to in person visits. Additional benefits were patient therapeutic effects from attending sessions from home, therapist convenience, and clinician growth. Conclusions: VHA CAT therapists used their inherent creativity to problem solve difficulties and make adaptations for CAT telehealth adoption. Future studies may explore CAT telehealth sustainment and its effectiveness on clinical processes and outcomes.
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    Real-world use and outcomes of dolutegravir-containing antiretroviral therapy in HIV and tuberculosis co-infection: a site survey and cohort study in sub-Saharan Africa
    (Wiley, 2022) Romo, Matthew L.; Brazier, Ellen; Mahambou-Nsondé, Dominique; De Waal, Reneé; Sekaggya-Wiltshire, Christine; Chimbetete, Cleophas; Muyindike, Winnie R.; Murenzi, Gad; Kunzekwenyika, Cordelia; Tiendrebeogo, Thierry; Muhairwe, Josephine A.; Lelo, Patricia; Dzudie, Anastase; Twizere, Christelle; Rafael, Idiovino; Ezechi, Oliver C.; Diero, Lameck; Yotebieng, Marcel; Fenner, Lukas; Wools-Kaloustian, Kara K.; Shah, N. Sarita; Nash, Denis; International epidemiology Databases to Evaluate AIDS (IeDEA); Medicine, School of Medicine
    Introduction: Dolutegravir is being scaled up globally as part of antiretroviral therapy (ART), but for people with HIV and tuberculosis co-infection, its use is complicated by a drug-drug interaction with rifampicin requiring an additional daily dose of dolutegravir. This represents a disadvantage over efavirenz, which does not have a major drug-drug interaction with rifampicin. We sought to describe HIV clinic practices for prescribing concomitant dolutegravir and rifampicin, and characterize virologic outcomes among patients with tuberculosis co-infection receiving dolutegravir or efavirenz. Methods: Within the four sub-Saharan Africa regions of the International epidemiology Databases to Evaluate AIDS consortium, we conducted a site survey (2021) and a cohort study (2015-2021). The cohort study used routine clinical data and included patients newly initiating or already receiving dolutegravir or efavirenz at the time of tuberculosis diagnosis. Patients were followed from tuberculosis diagnosis until viral suppression (<1000 copies/ml), a competing event (switching ART regimen; loss to program/death) or administrative censoring at 12 months. Results: In the survey, 86 of 90 (96%) HIV clinics in 18 countries reported prescribing dolutegravir to patients who were receiving rifampicin as part of tuberculosis treatment, with 77 (90%) reporting that they use twice-daily dosing of dolutegravir, of which 74 (96%) reported having 50 mg tablets available to accommodate twice-daily dosing. The cohort study included 3563 patients in 11 countries, with 67% newly or recently initiating ART. Among patients receiving dolutegravir (n = 465), the cumulative incidence of viral suppression was 58.9% (95% confidence interval [CI]: 54.3-63.3%), switching ART regimen was 4.1% (95% CI: 2.6-6.2%) and loss to program/death was 23.4% (95% CI: 19.7-27.4%). Patients receiving dolutegravir had improved viral suppression compared with patients receiving efavirenz who had a tuberculosis diagnosis before site dolutegravir availability (adjusted subdistribution hazard ratio [aSHR]: 1.47, 95% CI: 1.28-1.68) and after site dolutegravir availability (aSHR 1.28, 95% CI: 1.08-1.51). Conclusions: At a programmatic level, dolutegravir was being widely prescribed in sub-Saharan Africa for people with HIV and tuberculosis co-infection with a dose adjustment for the drug-drug interaction with rifampicin. Despite this more complex regimen, our cohort study revealed that dolutegravir did not negatively impact viral suppression.
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    The Tuberculosis Sentinel Research Network (TB-SRN) of the International epidemiology Databases to Evaluate AIDS (IeDEA): protocol for a prospective cohort study in Africa, Southeast Asia and Latin America
    (BMJ, 2024-01-09) Enane, Leslie A.; Duda, Stephany N.; Chanyachukul, Thida; Bolton-Moore, Carolyn; Navuluri, Neelima; Messou, Eugène; Mbonze, Nana; McDade, LaQuita R.; Figueiredo, Marina Cruvinel; Ross, Jeremy; Evans, Denise; Diero, Lameck; Akpata, Robert; Zotova, Natalia; Freeman, Aimee; Pierre, Marie Flore; Rupasinghe, Dhanushi; Ballif, Marie; Byakwaga, Helen; de Castro, Nathalie; Tabala, Martine; Sterling, Timothy R.; Sohn, Annette H.; Fenner, Lukas; Wools-Kaloustian, Kara; Poda, Armel; Yotebieng, Marcel; Huebner, Robin; Marcy, Olivier; International epidemiology Databases to Evaluate AIDS; Pediatrics, School of Medicine
    Introduction: Tuberculosis (TB) is a leading infectious cause of death globally. It is the most common opportunistic infection in people living with HIV, and the most common cause of their morbidity and mortality. Following TB treatment, surviving individuals may be at risk for post-TB lung disease. The TB Sentinel Research Network (TB-SRN) provides a platform for coordinated observational TB research within the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium. Methods and analysis: This prospective, observational cohort study will assess treatment and post-treatment outcomes of pulmonary TB (microbiologically confirmed or clinically diagnosed) among 2600 people aged ≥15 years, with and without HIV coinfection, consecutively enrolled at 16 sites in 11 countries, across 6 of IeDEA's global regions. Data regarding clinical and sociodemographic factors, mental health, health-related quality of life, pulmonary function, and laboratory and radiographic findings will be collected using standardised questionnaires and data collection tools, beginning from the initiation of TB treatment and through 12 months after the end of treatment. Data will be aggregated for proposed analyses. Ethics and dissemination: Ethics approval was obtained at all implementing study sites, including the Vanderbilt University Medical Center Human Research Protections Programme. Participants will provide informed consent; for minors, this includes both adolescent assent and the consent of their parent or primary caregiver. Protections for vulnerable groups are included, in alignment with local standards and considerations at sites. Procedures for requesting use and analysis of TB-SRN data are publicly available. Findings from TB-SRN analyses will be shared with national TB programmes to inform TB programming and policy, and disseminated at regional and global conferences and other venues.