Abstract WP312: The Association of Chronic Kidney Disease (CKD) With 30-day and 1-year Post Ischemic Stroke Mortality and Rehospitalization: Get With the Guidelines (GWTG) Stroke

Background: The extent to which CKD is associated with 30-day and 1-year post ischemic stroke mortality and rehospitalization rates has not been well studied. Methods: Data from 232,236 fee for service Medicare patients admitted with ischemic stroke to 1581 AHA GWTG-Stroke participating hospitals between January 2009 and December 2012 were analyzed. Estimated GFR in mL/min/1.73 m2 was determined based on the MDRD study equation categorized as: no CKD (GFR ≥60); stage 3a CKD (GFR 45-59); stage 3b CKD (GFR 30-44); stage 4 CKD, (GFR 15-29); stage 5 CKD (GFR <15 excluding those on dialysis). Dialysis was identified by ICD-9 codes. Multivariable Cox proportional hazards models adjusted for demographics, medical history, NIHSS, arrival hour, and hospital characteristics were used to determine the independent associations of CKD (reference group those without CKD) with mortality and readmission at 30 days and 1 year. Results: After adjustment, 30-days poststroke mortality was highest among those with CKD stage 5 (HR 1.94, 95%CI 1.72-2.18), even after excluding in-hospital mortality and patients discharged to hospice (HR 2.09, 95%CI 1.66-2.63). Unadjusted 1-year mortality and readmission rates were highest among patients on dialysis (Figure). After adjustment, 1-year post-stroke mortality remained highest among patients on dialysis (HR 2.19, 95%CI 2.08-2.31), even after excluding in-hospital mortality and discharge to hospice (HR 2.65, 95%CI 2.49-2.81). For those discharged alive, 30-day and 1-year rehospitalization rates were also highest among patients on dialysis (HR 2.10, 95%CI 1.95-2.26; HR 2.55, 95%CI 2.44-2.66, respectively) as was the 30-day and 1-year composite of mortality and rehospitalization (HR 2.04, 95%CI 1.90-2.18; HR 2.46, 95% CI 2.36-2.56, respectively). Conclusion: Among Medicare beneficiaries with acute ischemic stroke, poststroke mortality and rehospitalization varied by CKD stage and were highest among those with advanced CKD.

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Association of Kidney Function With 30-Day and 1-Year Poststroke Mortality and Hospital Readmission

Stroke ◽

10.1161/strokeaha.118.022011 ◽

2018 ◽

Vol 49 (12) ◽

pp. 2896-2903 ◽

Cited By ~ 5

Author(s):

Nada El Husseini ◽

Gregg C. Fonarow ◽

Eric E. Smith ◽

Christine Ju ◽

Shubin Sheng ◽

...

Keyword(s):

Ischemic Stroke ◽

Kidney Function ◽

Hospital Readmission ◽

Proportional Hazards ◽

Hospital Readmissions ◽

Cox Proportional Hazards ◽

Fee For Service ◽

Hospital Readmission Rates ◽

Cox Proportional Hazards Models ◽

Relevant Variables

Background and Purpose— Kidney dysfunction is common among patients hospitalized for ischemic stroke. Understanding the association of kidney disease with poststroke outcomes is important to properly adjust for case mix in outcome studies, payment models and risk-standardized hospital readmission rates. Methods— In this cohort study of fee-for-service Medicare patients admitted with ischemic stroke to 1579 Get With The Guidelines-Stroke participating hospitals between 2009 and 2014, adjusted multivariable Cox proportional hazards models were used to determine the independent associations of estimated glomerular filtration rate (eGFR) and dialysis status with 30-day and 1-year postdischarge mortality and rehospitalizations. Results— Of 204 652 patients discharged alive (median age [25th–75th percentile] 80 years [73.0–86.0], 57.6% women, 79.8% white), 48.8% had an eGFR ≥60, 26.5% an eGFR 45 to 59, 16.3% an eGFR 30 to 44, 5.1% an eGFR 15 to 29, 0.6% an eGFR <15 without dialysis, and 2.8% were receiving dialysis. Compared with eGFR ≥60, and after adjusting for relevant variables, eGFR <45 was associated with increased 30-day mortality with the risk highest among those with eGFR <15 without dialysis (hazard ratio [HR], 2.09; 95% CI, 1.66–2.63). An eGFR <60 was associated with increased 1-year poststroke mortality that was highest among patients on dialysis (HR, 2.65; 95% CI, 2.49–2.81). Dialysis was also associated with the highest 30-day and 1-year rehospitalization rates (HR, 2.10; 95% CI, 1.95–2.26 and HR, 2.55; 95% CI, 2.44–2.66, respectively) and 30-day and 1-year composite of mortality and rehospitalization (HR, 2.04; 95% CI, 1.90–2.18 and HR, 2.46; 95% CI, 2.36–2.56, respectively). Conclusions— Within the first year after index hospitalization for ischemic stroke, eGFR and dialysis status on admission are associated with poststroke mortality and hospital readmissions. Kidney function should be included in risk-stratification models for poststroke outcomes.

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Abstract P005: Comparative Effectiveness of Rivaroxaban versus Warfarin for the Treatment of Patients with Non-valvular Atrial Fibrillation

Circulation ◽

10.1161/circ.133.suppl_1.p005 ◽

2016 ◽

Vol 133 (suppl_1) ◽

Author(s):

Faye L Norby ◽

Lindsay G Bengtson ◽

Lin Y Chen ◽

Richard F MacLehose ◽

Pamela L Lutsey ◽

...

Keyword(s):

Atrial Fibrillation ◽

Ischemic Stroke ◽

Real World ◽

Proportional Hazards ◽

Large Population ◽

Population Based ◽

Cox Proportional Hazards ◽

Gi Bleeding ◽

Cox Proportional Hazards Models ◽

The Us

Background: Rivaroxaban is a novel oral anticoagulant approved in the US in 2011 for prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation (NVAF). Information on risks and benefits among rivaroxaban users in real-world populations is limited. Methods: We used data from the US MarketScan Commercial and Medicare Supplemental databases between 2010 and 2013. We selected patients with a history of NVAF and initiating rivaroxaban or warfarin. Rivaroxaban users were matched with up to 5 warfarin users by age, sex, database enrollment date and drug initiation date. Ischemic stroke, intracranial bleeding (ICB), myocardial infarction (MI), and gastrointestinal (GI) bleeding outcomes were defined by ICD-9-CM codes in an inpatient claim after drug initiation date. Cox proportional hazards models were used to assess the association between rivaroxaban vs. warfarin use and outcomes adjusting for age, sex, and CHA2DS2-VASc score. Separate models were used to compare a) new rivaroxaban users with new warfarin users, and b) switchers from warfarin to rivaroxaban to continuous warfarin users. Results: Our analysis included 34,998 rivaroxaban users matched to 102,480 warfarin users with NVAF (39% female, mean age 71), in which 487 ischemic strokes, 179 ICB, 647 MI, and 1353 GI bleeds were identified during a mean follow-up of 9 months. Associations of rivaroxaban vs warfarin were similar in new users and switchers; therefore we pooled both analyses. Rivaroxaban users had lower rates of ICB (hazard ratio (HR) (95% confidence interval (CI)) = 0.72 (0.46, 1.12))) and ischemic stroke (HR (95% CI) = 0.88 (0.68, 1.13)), but higher rates of GI bleeding (HR (95% CI) = 1.15 (1.01, 1.33)) when compared to warfarin users (table). Conclusion: In this large population-based study of NVAF patients, rivaroxaban users had a non-significant lower risk of ICB and ischemic stroke than warfarin users, but a higher risk of GI bleeding. These real-world findings are comparable to results reported in published clinical trials.

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Sodium Fluctuations and Mortality in a General Hospitalized Population

Kidney & Blood Pressure Research ◽

10.1159/000500916 ◽

2019 ◽

Vol 44 (4) ◽

pp. 604-614 ◽

Cited By ~ 3

Author(s):

Gianmarco Lombardi ◽

Pietro Manuel Ferraro ◽

Luca Calvaruso ◽

Alessandro Naticchia ◽

Silvia D’Alonzo ◽

...

Keyword(s):

Hospital Mortality ◽

Hospital Admission ◽

Hospital Stay ◽

Proportional Hazards ◽

Medical Center ◽

Cerebrovascular Diseases ◽

Linear Increase ◽

Cox Proportional Hazards ◽

Hospital Death ◽

Cox Proportional Hazards Models

Background/Aims: Aim of our study was to describe the association between natremia (Na) fluctuation and hospital mortality in a general population admitted to a tertiary medical center. Methods: We performed a retrospective observational cohort study on the patient population admitted to the Fondazione Policlinico A. Gemelli IRCCS Hospital between January 2010 and December 2014 with inclusion of adult patients with at least 2 Na values available and with a normonatremic condition at hospital admission. Patients were categorized according to all Na values recorded during hospital stay in the following groups: normonatremia, hyponatremia, hypernatremia, and mixed dysnatremia. The difference between the highest or the lowest Na value reached during hospital stay and the Na value read at hospital admission was used to identify the maximum Na fluctuation. Cox proportional hazards models were used to estimate hazard ratios (HRs) for in-hospital death in the groups with dysnatremias and across quartiles of Na fluctuation. Covariates assessed were age, sex, highest and lowest Na level, Charlson/Deyo score, cardiovascular diseases, cerebrovascular diseases, dementia, congestive heart failure, severe kidney disease, estimated glomerular filtration rate, and number of Na measurements during hospital stay. Results: 46,634 admissions matched inclusion criteria. Incident dysnatremia was independently associated with in-hospital mortality (hyponatremia: HR 3.11, 95% CI 2.53, 3.84, p < 0.001; hypernatremia: HR 5.12, 95% CI 3.94, 6.65, p < 0.001; mixed-dysnatremia: HR 4.94, 95% CI 3.08, 7.92, p < 0.001). We found a higher risk of in-hospital death by linear increase of quartile of Na fluctuation (p trend <0.001) irrespective of severity of dysnatremia (HR 2.34, 95% CI 1.55, 3.54, p < 0.001, for the highest quartile of Na fluctuation compared with the lowest). Conclusions: Incident dysnatremia is associated with higher hospital mortality. Fluctuation of Na during hospital stay is a prognostic marker for hospital death independent of dysnatremia severity.

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Minimum Threshold of Bariatric Surgical Weight Loss for Initial Diabetes Remission

10.2337/figshare.15113349.v1 ◽

2021 ◽

Author(s):

Douglas Barthold ◽

Elizabeth Brouwer ◽

Lee J. Barton ◽

David E. Arterburn ◽

Anirban Basu ◽

...

Keyword(s):

Bariatric Surgery ◽

Weight Loss ◽

Proportional Hazards ◽

Reference Group ◽

Diabetes Remission ◽

Cox Proportional Hazards ◽

Proportional Hazards Models ◽

Cox Proportional Hazards Models ◽

Design And Methods ◽

Time Varying Covariates

Objective: There are few studies testing the amount of weight loss necessary to achieve initial remission of type 2 diabetes (T2DM) following bariatric surgery and no published studies using weight loss to predict initial T2DM remission in sleeve gastrectomy (SG) patients. Research Design and Methods: Cox proportional hazards models examined the relationship between initial T2DM remission and percent total weight loss (%TWL) after bariatric surgery. Categories of %TWL were included in the model as time-varying covariates. Results: Patients (N=5,928) were 73% female, 49.8+10.3 years old, had BMI of 43.8+6.92 kg/m2, and 57% had Roux-en-Y gastric bypass (RYGB). Over an average follow-up of 5.9 years, 71% of patients experienced initial remission of their T2DM (mean time to remission 1.0 year). Using 0-5% TWL as the reference group in Cox proportional hazards models, patients were more likely to remit with each 5% increase in TWL until 20% TWL (range from HR=1.97 to 2.92). When categories above >25% TWL were examined, all had a likelihood of initial remission similar to 20-25% TWL. Patients who achieved >20% TWL were more likely to achieve initial T2DM remission than patients with 0-5% TWL, even if they were using insulin at the time of surgery. Conclusions: Weight loss after bariatric surgery is strongly associated with initial T2DM remission; however, above a threshold of 20% TWL, rates of initial T2DM remission did not increase substantially. Achieving this threshold is also associated with initial remission even in patients who traditionally experience lower rates of remission, such as patients taking insulin.

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Relationship Between Change in Serum Uric Acid and Ischemic Stroke in Chinese Hypertensive Patients

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.717128 ◽

2021 ◽

Vol 8 ◽

Author(s):

Qiu-hong Tan ◽

Lin Liu ◽

Yu-qing Huang ◽

Yu-ling Yu ◽

Jia-yi Huang ◽

...

Keyword(s):

Uric Acid ◽

Ischemic Stroke ◽

Serum Uric Acid ◽

Proportional Hazards ◽

Cox Proportional Hazards ◽

Elevated Risk ◽

Rank Test ◽

Hypertensive Patients ◽

Cox Proportional Hazards Models ◽

The Relationship

Background: Limited studies focused on the association between serum uric acid (SUA) change with ischemic stroke, and their results remain controversial. The present study aimed to investigate the relationship between change in SUA with ischemic stroke among hypertensive patients.Method: This was a retrospective cohort study. We recruited adult hypertensive patients who had two consecutive measurements of SUA levels from 2013 to 2014 and reported no history of stroke. Change in SUA was assessed as SUA concentration measured in 2014 minus SUA concentration in 2013. Multivariable Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). The Kaplan–Meier analysis and log-rank test were performed to quantify the difference in cumulative event rate. Additionally, subgroup analysis and interaction tests were conducted to investigate heterogeneity.Results: A total of 4,628 hypertensive patients were included, and 93 cases of ischemic stroke occurred during the mean follow-up time of 3.14 years. Participants were categorized into three groups according to their SUA change tertiles [low (SUA decrease substantially): <-32.6 μmol/L; middle (SUA stable): ≥-32.6 μmol/L, <40.2 μmol/L; high (SUA increase substantially): ≥40.2 μmol/L]. In the fully adjusted model, setting the SUA stable group as reference, participants in the SUA increase substantially group had a significantly elevated risk of ischemic stroke [HR (95% CI), 1.76 (1.01, 3.06), P = 0.0451], but for the SUA decrease substantially group, the hazard effect was insignificant [HR (95% CI), 1.31 (0.75, 2.28), P = 0.3353]. Age played an interactive role in the relationship between SUA change and ischemic stroke. Younger participants (age < 65 years) tended to have a higher risk of ischemic stroke when SUA increase substantially.Conclusion: SUA increase substantially was significantly correlated with an elevated risk of ischemic stroke among patients with hypertension.

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Death of a Partner and Risks of Ischemic Stroke and Intracerebral Hemorrhage: A Nationwide Danish Matched Cohort Study

Journal of the American Heart Association ◽

10.1161/jaha.120.018763 ◽

2020 ◽

Vol 9 (23) ◽

Author(s):

Morten Fenger‐Grøn ◽

Ida Paulsen Møller ◽

Henrik Schou Pedersen ◽

Lars Frost ◽

Annelli Sandbæk ◽

...

Keyword(s):

Ischemic Stroke ◽

Intracerebral Hemorrhage ◽

Proportional Hazards ◽

Reference Group ◽

Absolute Risk ◽

Cox Proportional Hazards ◽

Study Cohort ◽

Calendar Time ◽

Loved One ◽

Quality Register

Background Stress has been reported to trigger stroke, and the death of a loved one is a potentially extremely stressful experience. Yet, previous studies have yielded conflicting findings of whether bereavement is associated with stroke risk, possibly because of insufficient distinction between ischemic stroke (IS) and intracerebral hemorrhage (ICH). We therefore examined the associations between bereavement and IS and ICH separately in contemporary care settings using nationwide high‐quality register resources. Methods and Results The study cohort included all Danish individuals whose partner died between 2002 and 2016 and a reference group of cohabiting individuals matched 1:2 on sex, age, and calendar time. Cox proportional hazards regression was used to estimate adjusted hazard ratios (aHRs) and corresponding 95% CIs during up to 5 years follow‐up. During the study period, 278 758 individuals experienced partner bereavement, of whom 7684 had an IS within the subsequent 5 years (aHR, 1.11; CI, 1.08–1.14 when compared with nonbereaved referents) and 1139 experienced an ICH (aHR, 1.13; CI, 1.04–1.23). For ICH, the estimated association tended to be stronger within the initial 30 days after partner death (aHR, 1.66; CI, 1.06–2.61), especially in women (aHR, 1.99; CI, 1.06–3.75), but the statistical precision was low. In absolute numbers, the cumulative incidence of IS at 30 days was 0.73 per 1000 in bereaved individuals versus 0.63 in their referents, and the corresponding figures for ICH were 0.13 versus 0.08. Conclusions Statistically significant positive associations with partner bereavement were documented for both IS and ICH risk, for ICH particularly in the short term. However, absolute risk differences were small.

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Multivitamin Use and Risk of Stroke Mortality

Stroke ◽

10.1161/strokeaha.114.008270 ◽

2015 ◽

Vol 46 (5) ◽

pp. 1167-1172 ◽

Cited By ~ 4

Author(s):

Jia-Yi Dong ◽

Hiroyasu Iso ◽

Akihiko Kitamura ◽

Akiko Tamakoshi

Keyword(s):

Ischemic Stroke ◽

Confidence Interval ◽

Fruits And Vegetables ◽

Proportional Hazards ◽

Vegetable Intake ◽

Significant Risk ◽

Cox Proportional Hazards ◽

Stroke Mortality ◽

Risk Of Death ◽

Multivitamin Use

Background and Purpose— An effect of multivitamin supplement on stroke risk is uncertain. We aimed to examine the association between multivitamin use and risk of death from stroke and its subtypes. Methods— A total of 72 180 Japanese men and women free from cardiovascular diseases and cancers at baseline in 1988 to 1990 were followed up until December 31, 2009. Lifestyles including multivitamin use were collected using self-administered questionnaires. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) of total stroke and its subtypes in relation to multivitamin use. Results— During a median follow-up of 19.1 years, we identified 2087 deaths from stroke, including 1148 ischemic strokes and 877 hemorrhagic strokes. After adjustment for potential confounders, multivitamin use was associated with lower but borderline significant risk of death from total stroke (HR, 0.87; 95% confidence interval, 0.76–1.01), primarily ischemic stroke (HR, 0.80; 95% confidence interval, 0.63–1.01), but not hemorrhagic stroke (HR, 0.96; 95% confidence interval, 0.78–1.18). In a subgroup analysis, there was a significant association between multivitamin use and lower risk of mortality from total stroke among people with fruit and vegetable intake <3 times/d (HR, 0.80; 95% confidence interval, 0.65–0.98). That association seemed to be more evident among regular users than casual users. Similar results were found for ischemic stroke. Conclusions— Multivitamin use, particularly frequent use, was associated with reduced risk of total and ischemic stroke mortality among Japanese people with lower intake of fruits and vegetables.

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ACUTE CARE UTILIZATION IN OLDER ADULTS LIVING UNDIAGNOSED OR UNAWARE OF DEMENTIA

Innovation in Aging ◽

10.1093/geroni/igz038.2707 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S739-S739

Author(s):

Halima Amjad ◽

David L Roth ◽

Jin Huang ◽

Jennifer L Wolff ◽

Quincy M Samus

Keyword(s):

Proportional Hazards ◽

Cox Proportional Hazards ◽

Care Utilization ◽

Fee For Service ◽

Dementia Diagnosis ◽

Medicare Claims ◽

Cox Proportional Hazards Models ◽

Acute Care Utilization ◽

Ed Visits ◽

Nationally Representative

Abstract Most individuals with dementia are undiagnosed or they/their families are unaware of the diagnosis. Implications of dementia diagnosis and awareness are poorly understood. Our objective was to determine whether undiagnosed dementia or unawareness increases risk of hospitalization or emergency department (ED) visits, outcomes with recognized risk in diagnosed dementia. We linked National Health and Aging Trends Study (NHATS) data to fee-for-service Medicare claims for 4,311 community-living participants in the nationally representative cohort. We assessed probable versus no dementia using validated NHATS dementia criteria, undiagnosed versus diagnosed using Medicare claims, and aware versus unaware using NHATS self or proxy report of diagnosis. Cox proportional hazards models evaluated hospitalization and ED visit risk by time-varying dementia diagnosis and awareness status, adjusting for sociodemographic characteristics, functional impairment, medical comorbidities, and prior hospitalization. Compared to no dementia, persons with dementia who were unaware but diagnosed had greater risk of hospitalization (HR 1.66, 95% CI 1.26-2.19) and ED visits (HR 1.63, 95% CI 1.28-2.08). Persons unaware but diagnosed also had greater risk compared to persons aware and diagnosed (hospitalization HR 1.34, 95% CI 0.98-1.82; ED HR 1.38, 95% CI 1.05-1.83). Persons with undiagnosed dementia demonstrated hospitalization risk similar to persons with no dementia (HR 1.02, 95% CI 0.79-1.31) and similar or potentially lower than persons aware and diagnosed (HR 0.82, 95% CI 0.61-1.10); ED visit findings were similar. Results suggest that being unaware of dementia diagnosis may affect healthcare utilization. Strategies to improve communication and understanding of dementia could potentially reduce hospitalizations and ED visits.

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Abstract WP213: Association Between Thoracic Aorta Surgery and Long Term Risk of Stroke in Adults

Stroke ◽

10.1161/str.51.suppl_1.wp213 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Tashfin Huq ◽

Marialaura Simonetto ◽

Babak B Navi ◽

Hooman Kamel

Keyword(s):

Ischemic Stroke ◽

Thoracic Aorta ◽

Stroke Risk ◽

Proportional Hazards ◽

Perioperative Period ◽

Cox Proportional Hazards ◽

Medicare Beneficiaries ◽

Increased Risk ◽

Nationally Representative

Introduction: Thoracic aorta surgery carries a risk of perioperative stroke, but the long-term incidence of stroke after the perioperative period in these patients remains unclear. We therefore assessed the long-term risk of stroke in patients who underwent thoracic aorta repair. Methods: We performed a retrospective cohort study using 2008-2015 claims data from a nationally representative 5% sample of Medicare beneficiaries. Our exposure of interest was thoracic aorta surgery, defined using ICD-9-CM hospital procedure codes for endovascular graft implantation (39.73) or surgical resection and replacement (38.45). Our primary outcome was ischemic stroke, defined using previously validated ICD-9-CM diagnosis codes. Patients with stroke during the index surgical hospitalization were excluded, since our focus was on long-term stroke risk after the perioperative period . Cox proportional hazards analysis was used to examine the association between thoracic aorta surgery and stroke risk after adjustment for demographics and vascular risk factors. Given a clear violation of the proportional hazards assumption, we calculated period-specific risk estimates. Results: Among 1,751,719 beneficiaries (mean age 73 ±8 years), 1,402 underwent thoracic aorta repair. During 4.6 ±2.2 years of follow-up, 62,702 patients were diagnosed with ischemic stroke. The incidence of stroke was 1.24% (95% CI, 0.93-1.66%) per year after thoracic aorta repair compared to 0.77% (95% CI, 0.76-0.78%) per year in patients without thoracic aorta surgery. In adjusted models, there was an increased risk of stroke in the first 120 days after discharge from thoracic aorta surgery (HR, 2.1; 95% CI, 1.2-3.7), but no heightened risk was seen beyond 120 days after discharge from surgery (HR, 0.7; 95% CI, 0.5-1.0). Conclusions: In a large sample of Medicare beneficiaries, thoracic aorta surgery was associated with an increased risk of ischemic stroke in the first 120 days after hospital discharge, but there was no excess risk beyond that time point.

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Abstract P048: Risk Factors for Severe Hypoglycemia Differ in Black and White Older Adults With Diabetes: the Atherosclerosis Risk in Communities (ARIC) Study

Circulation ◽

10.1161/circ.135.suppl_1.p048 ◽

2017 ◽

Vol 135 (suppl_1) ◽

Author(s):

Alexandra K Lee ◽

Bethany Warren ◽

Clare J Lee ◽

Elbert S Huang ◽

A. Richey Sharrett ◽

...

Keyword(s):

Risk Factors ◽

Proportional Hazards ◽

Severe Hypoglycemia ◽

Cox Proportional Hazards ◽

Emergency Department Visits ◽

Fee For Service ◽

Diabetes Medication ◽

C Statistic ◽

Cox Proportional Hazards Models ◽

Blacks And Whites

Introduction: Blacks with diabetes have roughly twice the rate of severe hypoglycemia compared to whites with diabetes; it is unclear whether hypoglycemia risk factors identified in studies of white participants are similarly associated with hypoglycemia in blacks. Methods: We included ARIC participants aged 65+ at Visit 4 (1996-1998) who had Medicare fee-for-service Part B and diagnosed diabetes. We identified severe hypoglycemic events through 2013 using ICD-9 codes from hospitalizations, emergency department visits, and ambulance services. We evaluated previously identified risk factors: age, sex, chronic kidney disease (CKD), diabetes medication use, obesity, cognition, glycemic control, and number of comorbidities. We stratified Cox proportional hazards models by race and used Harrell’s C-statistic to compare discrimination. Results: There were 33 hypoglycemic events in 135 black participants and 43 hypoglycemic events in 319 white participants (incidence rate 2.8 vs. 1.5 per 100 person-years, p<0.01). Most risk factors had similar associations with risk of hypoglycemia in blacks and whites, with some notable exceptions. Obesity was associated with greater risk in blacks but not whites ( Table ). CKD was more strongly associated with risk in blacks than whites. Type of diabetes medication was associated with risk in whites but not in blacks. The C-statistic suggested better model discrimination in whites (C=0.795) than in blacks (C=0.759), but confidence intervals were wide. Conclusion: The direction and strength of risk factors for hypoglycemia may differ for blacks and whites. It is unclear why the relative importance of risk factors for hypoglycemia differ between whites and blacks. These data suggest that the mechanism by which CKD influences hypoglycemia risk may be decreased renal gluconeogenesis in blacks and reduced insulin clearance in whites. Additional research is needed to understand those factors that contribute to hypoglycemia risk in blacks and may underlie health disparities.

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