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Item A comparison of techniques for deriving clustering and switching scores from verbal fluency word lists(Frontiers Media, 2022-09-14) Bushnell, Justin; Svaldi, Diana; Ayers, Matthew R.; Gao, Sujuan; Unverzagt, Frederick; Del Gaizo, John; Wadley, Virginia G.; Kennedy, Richard; Goñi, Joaquín; Clark, David Glenn; Neurology, School of MedicineObjective: To compare techniques for computing clustering and switching scores in terms of agreement, correlation, and empirical value as predictors of incident cognitive impairment (ICI). Methods: We transcribed animal and letter F fluency recordings on 640 cases of ICI and matched controls from a national epidemiological study, amending each transcription with word timings. We then calculated clustering and switching scores, as well as scores indexing speed of responses, using techniques described in the literature. We evaluated agreement among the techniques with Cohen's κ and calculated correlations among the scores. After fitting a base model with raw scores, repetitions, and intrusions, we fit a series of Bayesian logistic regression models adding either clustering and switching scores or speed scores, comparing the models in terms of several metrics. We partitioned the ICI cases into acute and progressive cases and repeated the regression analysis for each group. Results: For animal fluency, we found that models with speed scores derived using the slope difference algorithm achieved the best values of the Watanabe-Akaike Information Criterion (WAIC), but with good net reclassification improvement (NRI) only for the progressive group (8.2%). For letter fluency, different models excelled for prediction of acute and progressive cases. For acute cases, NRI was best for speed scores derived from a network model (3.4%), while for progressive cases, the best model used clustering and switching scores derived from the same network model (5.1%). Combining variables from the best animal and letter F models led to marginal improvements in model fit and NRI only for the all-cases and acute-cases analyses. Conclusion: Speed scores improve a base model for predicting progressive cognitive impairment from animal fluency. Letter fluency scores may provide complementary information.Item A locus at 19q13.31 significantly reduces the ApoE ε4 risk for Alzheimer's Disease in African Ancestry(Public Library of Science, 2022-07-05) Rajabli, Farid; Beecham, Gary W.; Hendrie, Hugh C.; Baiyewu, Olusegun; Ogunniyi, Adesola; Gao, Sujuan; Kushch, Nicholas A.; Lipkin-Vasquez, Marina; Hamilton-Nelson, Kara L.; Young, Juan I.; Dykxhoorn, Derek M.; Nuytemans, Karen; Kunkle, Brian W.; Wang, Liyong; Jin, Fulai; Liu, Xiaoxiao; Feliciano-Astacio, Briseida E.; Alzheimer’s Disease Sequencing Project; Alzheimer’s Disease Genetic Consortium; Schellenberg, Gerard D.; Dalgard, Clifton L.; Griswold, Anthony J.; Byrd, Goldie S.; Reitz, Christiane; Cuccaro, Michael L.; Haines, Jonathan L.; Pericak-Vance, Margaret A.; Vance, Jeffery M.; Psychiatry, School of MedicineAfrican descent populations have a lower Alzheimer disease risk from ApoE ε4 compared to other populations. Ancestry analysis showed that the difference in risk between African and European populations lies in the ancestral genomic background surrounding the ApoE locus (local ancestry). Identifying the mechanism(s) of this protection could lead to greater insight into the etiology of Alzheimer disease and more personalized therapeutic intervention. Our objective is to follow up the local ancestry finding and identify the genetic variants that drive this risk difference and result in a lower risk for developing Alzheimer disease in African ancestry populations. We performed association analyses using a logistic regression model with the ApoE ε4 allele as an interaction term and adjusted for genome-wide ancestry, age, and sex. Discovery analysis included imputed SNP data of 1,850 Alzheimer disease and 4,331 cognitively intact African American individuals. We performed replication analyses on 63 whole genome sequenced Alzheimer disease and 648 cognitively intact Ibadan individuals. Additionally, we reproduced results using whole-genome sequencing of 273 Alzheimer disease and 275 cognitively intact admixed Puerto Rican individuals. A further comparison was done with SNP imputation from an additional 8,463 Alzheimer disease and 11,365 cognitively intact non-Hispanic White individuals. We identified a significant interaction between the ApoE ε4 allele and the SNP rs10423769_A allele, (β = -0.54,SE = 0.12,p-value = 7.50x10-6) in the discovery data set, and replicated this finding in Ibadan (β = -1.32,SE = 0.52,p-value = 1.15x10-2) and Puerto Rican (β = -1.27,SE = 0.64,p-value = 4.91x10-2) individuals. The non-Hispanic Whites analyses showed an interaction trending in the "protective" direction but failing to pass a 0.05 significance threshold (β = -1.51,SE = 0.84,p-value = 7.26x10-2). The presence of the rs10423769_A allele reduces the odds ratio for Alzheimer disease risk from 7.2 for ApoE ε4/ε4 carriers lacking the A allele to 2.1 for ApoE ε4/ε4 carriers with at least one A allele. This locus is located approximately 2 mB upstream of the ApoE locus, in a large cluster of pregnancy specific beta-1 glycoproteins on chromosome 19 and lies within a long noncoding RNA, ENSG00000282943. This study identified a new African-ancestry specific locus that reduces the risk effect of ApoE ε4 for developing Alzheimer disease. The mechanism of the interaction with ApoEε4 is not known but suggests a novel mechanism for reducing the risk for ε4 carriers opening the possibility for potential ancestry-specific therapeutic intervention.Item Accelerating diversity in Alzheimer's disease research by partnering with a community advisory board(Wiley, 2023-05-28) Pena-Garcia, Alex; Richards, Ralph; Richards, Mollie; Campbell, Christopher; Mosley, Hank; Asper, Joseph; Eliacin, Johanne; Polsinelli, Angelina; Apostolova, Liana; Hendrie, Hugh; Tackett, Andrew; Elliott, Caprice; Van Heiden, Sarah; Gao, Sujuan; Saykin, Andrew; Wang, Sophia; Medicine, School of MedicineIntroduction: Community advisory boards (CABs) and researcher partnerships present a promising opportunity to accelerate enrollment of underrepresented groups (URGs). We outline the framework for how the CAB and researchers at the Indiana Alzheimer's Disease Research Center (IADRC) partnered to accelerate URG participation in AD neuroimaging research. Methods: CAB and the IADRC researchers partnered to increase the CAB's impact on URG study enrollment through community and research interactions. Community interactions included the CAB collaboratively building a network of URG focused community organizations and collaborating with those URG-focused organizations to host IADRC outreach and recruitment events. Research interactions included direct impact (CAB members referring themselves or close contacts as participants) and strategic impact, mainly by the CAB working with researchers to develop and refine URG focused outreach and recruitment strategies for IADRC and affiliated studies to increase URG representation. We created a database infrastructure to measure how these interactions impacted URG study enrollment. Results: Out of the 354 URG research referrals made to the IADRC between October 2019 and December 2022, 267 referrals were directly referred by the CAB (N = 36) or from community events in which CAB members organized and/or volunteered at (N = 231). Out of these 267 referrals, 34 were enrolled in IADRC and 2 were enrolled in Indiana University Longitudinal Early Onset AD Study (IU LEADS). Of note, both studies require the prospective participants to be willing to do MRI and PET scans. As of December 2022, 30 out of the 34 enrolled participants have received a consensus diagnosis; the majority were cognitively normal (64.7%), with the remainder having mild cognitive impairment (17.6%) or early-stage AD (2.9%). Discussion: The IADRC CAB-researcher partnership had a measurable impact on the enrollment of African American/Black adults in AD neuroimaging studies. Future studies will need to test whether this conceptual model works for other sites and for other URGs.Item Adherence and Tolerability of Alzheimer's Disease Medications: A Pragmatic Randomized Trial(Wiley, 2017-07) Campbell, Noll L.; Perkins, Anthony J.; Gao, Sujuan; Skaar, Todd C.; Li, Lang; Hendrie, Hugh C.; Fowler, Nicole; Callahan, Christopher M.; Boustani, Malaz A.; Department of Medicine, IU School of MedicineBACKGROUND/OBJECTIVES: Post-marketing comparative trials describe medication use patterns in diverse, real-world populations. Our objective was to determine if differences in rates of adherence and tolerability exist among new users to acetylcholinesterase inhibitors (AChEI's). DESIGN: Pragmatic randomized, open label comparative trial of AChEI's currently available in the United States. SETTING: Four memory care practices within four healthcare systems in the greater Indianapolis area. PARTICIPANTS: Eligibility criteria included older adults with a diagnosis of possible or probable Alzheimer's disease (AD) who were initiating treatment with an AChEI. Participants were required to have a caregiver to complete assessments, access to a telephone, and be able to understand English. Exclusion criteria consisted of a prior severe adverse event from AChEIs. INTERVENTION: Participants were randomized to one of three AChEIs in a 1:1:1 ratio and followed for 18 weeks. MEASUREMENTS: Caregiver-reported adherence, defined as taking or not taking study medication, and caregiver-reported adverse events, defined as the presence of an adverse event. RESULTS: 196 participants were included with 74.0% female, 30.6% African Americans, and 72.9% who completed at least twelfth grade. Discontinuation rates after 18 weeks were 38.8% for donepezil, 53.0% for galantamine, and 58.7% for rivastigmine (P = .063) in the intent to treat analysis. Adverse events and cost explained 73.1% and 25.4% of discontinuation. No participants discontinued donepezil due to cost. Adverse events were reported by 81.2% of all participants; no between-group differences in total adverse events were statistically significant. CONCLUSIONS: This pragmatic comparative trial showed high rates of adverse events and cost-related non-adherence with AChEIs. Interventions improving adherence and persistence to AChEIs may improve AD management. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01362686 (https://clinicaltrials.gov/ct2/show/NCT01362686).Item Altered Cerebral Blood Flow in Older Adults with Alzheimer’s Disease: A Systematic Review(Springer, 2023) Swinford, Cecily G.; Risacher, Shannon L.; Wu, Yu-Chien; Apostolova, Liana G.; Gao, Sujuan; Bice, Paula J.; Saykin, Andrew J.; Radiology and Imaging Sciences, School of MedicineThe prevalence of Alzheimer’s disease is projected to reach 13 million in the U.S. by 2050. Although major efforts have been made to avoid this outcome, so far there are no treatments that can stop or reverse the progressive cognitive decline that defines Alzheimer’s disease. The utilization of preventative treatment before significant cognitive decline has occurred may ultimately be the solution, necessitating a reliable biomarker of preclinical/prodromal disease stages to determine which older adults are most at risk. Quantitative cerebral blood flow is a promising potential early biomarker for Alzheimer’s disease, but the spatiotemporal patterns of altered cerebral blood flow in Alzheimer’s disease are not fully understood. The current systematic review compiles the findings of 81 original studies that compared resting gray matter cerebral blood flow in older adults with mild cognitive impairment or Alzheimer’s disease and that of cognitively normal older adults and/or assessed the relationship between cerebral blood flow and objective cognitive function. Individuals with Alzheimer’s disease had relatively decreased cerebral blood flow in all brain regions investigated, especially the temporoparietal and posterior cingulate, while individuals with mild cognitive impairment had consistent results of decreased cerebral blood flow in the posterior cingulate but more mixed results in other regions, especially the frontal lobe. Most papers reported a positive correlation between regional cerebral blood flow and cognitive function. This review highlights the need for more studies assessing cerebral blood flow changes both spatially and temporally over the course of Alzheimer’s disease, as well as the importance of including potential confounding factors in these analyses.Item Anticholinergics Influence Transition from Normal Cognition to Mild Cognitive Impairment in Older Adults in Primary Care(Wiley, 2018) Campbell, Noll L.; Lane, Kathleen A.; Gao, Sujuan; Boustani, Malaz A.; Unverzagt, Fred; Medicine, School of MedicineStudy Objective To determine the influence of anticholinergic medications on transitions in cognitive diagnosis of older adults in primary care. Design This observational cohort study was conducted over a mean follow‐up of 3.2 years. Anticholinergic exposure was defined by pharmacy dispensing and claims records. Cognitive diagnosis was performed by an expert panel at baseline and annually up to 4 years. Data Source Medication exposure and other clinical data were extracted from the Indiana Network for Patient Care (INPC). The cognitive diagnosis was derived from a cognitive screening and diagnosis study. Participants A total of 350 adults 65 years and older without dementia and receiving primary care in a safety net health care system. Measurement and Main Results Cognitive diagnosis followed a two‐phase screening and consensus‐based neuropsychiatric examination to determine a baseline diagnosis as normal cognition, mild cognitive impairment (MCI), or dementia, with a follow‐up neuropsychiatric examination and consensus‐based diagnosis repeated annually. The Anticholinergic Cognitive Burden scale was used to identify anticholinergics dispensed up to 10 years before enrollment and annually throughout the study. A total standard daily dose of anticholinergics was calculated by using pharmacy dispensing data from the INPC. Among 350 participants, a total of 978 diagnostic assessments were completed over a mean follow‐up of 3.2 years. Compared with stable cognition, increasing use of strong anticholinergics calculated by total standard daily dose increased the odds of transition from normal cognition to MCI (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.01–1.31, p = 0.0342). Compared with stable MCI, strong anticholinergics did not influence the reversion of MCI to normal cognition (OR 0.95, 95% CI 0.86–1.05, p = 0.3266). Conclusion De‐prescribing interventions in older adults with normal cognition should test anticholinergics as potentially modifiable risk factors for cognitive impairment.Item Antidepressant Use and Depressive Symptoms in Intensive Care Unit Survivors(SHM, 2017) Wang, Sophia; Mosher, Chris; Gao, Sujuan; Kirk, Kayla; Lasiter, Sue; Khan, Sikandar; Kheir, You Na; Boustani, Malaz; Khan, Babar; Psychiatry, School of MedicineNearly 30% of intensive care unit (ICU) survivors have depressive symptoms 2-12 months after hospital discharge. We examined the prevalence of depressive symptoms and risk factors for depressive symptoms in 204 patients at their initial evaluation in the Critical Care Recovery Center (CCRC), an ICU survivor clinic based at Eskenazi Hospital in Indianapolis, Indiana. Thirty-two percent (N = 65) of patients had depressive symptoms on initial CCRC visit. For patients who are not on an antidepressant at their initial CCRC visit (N = 135), younger age and lower education level were associated with a higher likelihood of having depressive symptoms. For patients on an antidepressant at their initial CCRC visit (N = 69), younger age and being African American race were associated with a higher likelihood of having depressive symptoms. Future studies will need to confirm these findings and examine new approaches to increase access to depression treatment and test new antidepressant regimens for post-ICU depression.Item Antidepressant Use in the Elderly Is Associated With an Increased Risk of Dementia(Ovid Technologies (Wolters Kluwer) - Lippincott Williams & Wilkins, 2016-04) Wang, Chenkun; Gao, Sujuan; Hendrie, Hugh C.; Kesterson, Joe; Campbell, Noll L.; Shekhar, Anantha; Callahan, Christopher M.; Biostatistics, School of Public HealthA retrospective cohort study was conducted including 3688 patients age 60 years or older without dementia enrolled in a depression screening study in primary care clinics. Information on antidepressant use and incident dementia during follow-up was retrieved from electronic medical records. The Cox proportional hazard models were used to compare the risk for incident dementia among 5 participant groups: selective serotonin re-uptake inhibitors (SSRI) only, non-SSRI only (non-SSRI), mixed group of SSRI and non-SSRI, not on antidepressants but depressed, and not on antidepressants and not depressed. SSRI and non-SSRI users had significantly higher dementia risk than the nondepressed nonusers (hazard ratio [HR]=1.83, P=0.0025 for SSRI users and HR=1.50, P=0.004 for non-SSRI users). In addition, SSRIs users had significantly higher dementia risk than non-users with severe depression (HR=2.26, P=0.0005). Future research is needed to confirm our results in other populations and to explore potential mechanism underlying the observed association.Item Antihypertensive Medication and Dementia Risk in Older Adult African Americans with Hypertension: A Prospective Cohort Study(Springer, 2018-04) Murray, Michael D.; Hendrie, Hugh C.; Lane, Kathleen A.; Zheng, Mengjie; Ambuehl, Roberta; Li, Shanshan; Unverzagt, Frederick W.; Callahan, Christopher M.; Gao, Sujuan; Psychiatry, School of MedicineBACKGROUND: African Americans are especially at risk of hypertension and dementia. Antihypertensive medications reduce the risk of cardiovascular events, but may also reduce the risk of dementia. OBJECTIVE: To assess the longitudinal effects of antihypertensive medications and blood pressure on the onset of incident dementia in a cohort of African Americans. DESIGN: Prospective cohort. PARTICIPANTS: 1236 community-dwelling patients from an inner-city public health care system, aged 65 years and older, with a history of hypertension but no history of dementia, and who had at least three primary care visits and a prescription filled for any medication. MAIN MEASURES: Blood pressure was the average of three seated measurements. Dementia was diagnosed using a two-stage design, with a screening evaluation every 2 to 3 years followed by a comprehensive in-home clinical evaluation for those with a positive screen. Laboratory, inpatient and outpatient encounter data, coded diagnoses and procedures, and medication records were derived from a health information exchange. KEY RESULTS: Of the 1236 hypertensive participants without dementia at baseline, 114 (9%) developed incident dementia during follow-up. Individuals prescribed any antihypertensive medication (n = 816) were found to have a significantly reduced risk of dementia (HR = 0.57, 95% CI 0.37-0.88, p = 0.0114) compared to untreated hypertensive participants (n = 420). When this analysis was repeated including a variable indicating suboptimally treated blood pressure (> 140 mmHg systolic or >90 mmHg diastolic), the effect of antihypertensive medication was no longer statistically significant (HR = 0.65, 95% CI 0.32-1.30, p = 0.2217). CONCLUSIONS: Control of blood pressure in older adult African American patients with hypertension is a key intervention for preventing dementia, with similar benefits from most of the commonly available antihypertensive medications.Item APOE ε4 and the risk for Alzheimer disease and cognitive decline in African Americans and Yoruba(Cambridge University Press, 2014-06) Hendrie, Hugh C.; Murrell, Jill; Baiyewu, Olusegun; Lane, Kathleen A.; Purnell, Christianna; Ogunniyi, Adesola; Unverzagt, Frederick W.; Hall, Kathleen; Callahan, Christopher M.; Saykin, Andrew J.; Gureje, Oye; Hake, Ann; Foroud, Tatiana; Gao, Sujuan; Department of Psychiatry, IU School of MedicineBackground There is little information on the association of the APOEe4 allele and AD risk in African populations. In previous analyses from the Indianapolis-Ibadan dementia project, we have reported that APOE ε4 increased the risk for Alzheimer’s disease (AD) in African Americans but not in Yoruba. This study represents a replication of this earlier work using enriched cohorts and extending the analysis to include cognitive decline. Methods In this longitudinal study of two community dwelling cohorts of elderly Yoruba and African Americans, APOE genotyping was conducted from blood samples taken on or before 2001 (1,871 African Americans & 2,200 Yoruba). Mean follow up time was 8.5 years for African Americans and 8.8 years for Yoruba. The effects of heterozygosity or homozygosity of ε4 and of the possession of e4 on time to incident AD and on cognitive decline were determined using Cox’s proportional hazards regression and mixed effects models. Results After adjusting for covariates, one or two copies of the APOE ε4 allele were significant risk factors for incident AD (p < 0.0001) and cognitive decline in the African-American population (p < 0001). In the Yoruba, only homozygosity for APOE ε4 was a significant risk factor for AD (p = 0.0002) but not for cognitive decline (p = 0.2346), however, possession of an e4 allele was significant for both incident AD (p = 0.0489) and cognitive decline (p = 0.0425). Conclusions In this large longitudinal comparative study, APOE ε4 had a significant, but weaker, effect on incident AD and on cognitive decline in Yoruba than in African Americans. The reasons for these differences remain unclear.