Race, ethnicity, and state-by-state geographic variation in hemorrhagic stroke in dialysis patients

Warfarin Usage in Patients with Atrial Fibrillation Undergoing Hemodialysis in Indonesian Population

The data about the efficacy and safety of warfarin usage in atrial fibrillation (AF) in hemodialysis patients is still limited, especially in the Asia population. The population of this study was end-stage renal disease patients with AF who underwent hemodialysis. The design of the study was a retrospective observational cohort that collected the patient data from 2016 to 2019. The Cox regression model was applied to assess the effect of warfarin on the outcomes. We conducted a survival analysis by comparing Kaplan-Meier curves using the log-rank test. We also measured the time in therapeutic range as a quality indicator of warfarin usage. Among 444 hemodialysis patients, 126 patients with AF matched the inclusion criteria, 88 patients completely followed up. Half patients used warfarin. The mean age was 52.2 ± 12.97 years, the mean follow-up duration was 11 ± 10 months. We observed all-cause death in 86.4% of patients, ischemic stroke in 10.2%, and hemorrhagic stroke in 2.3% of patients. There were no significant differences in all-cause death, ischemic stroke, and hemorrhagic stroke. Warfarin use was not associated with a lower rate for death (HR 0.782; 95% CI, 0.494-1.237, P = 0.293) or ischemic stroke (HR 0.435; 95% CI, 0.103-1.846, P = 0.259) or hemorrhagic stroke (HR 0.564; 95% CI, 0.034-9.386, P = 0.689). None of the patients reach the time in the therapeutic range >65%. Our findings suggest that warfarin has no association with mortality, ischemic stroke, and hemorrhagic stroke events rate in atrial fibrillation patients who underwent hemodialysis in the Indonesian population.

Ethnic and Racial Variation in Intracerebral Hemorrhage Risk Factors and Risk Factor Burden

Importance

Black and Hispanic individuals have an increased risk of intracerebral hemorrhage (ICH) compared with their White counterparts, but no large studies of ICH have been conducted in these disproportionately affected populations.

Objective

To examine the prevalence, odds, and population attributable risk (PAR) percentage for established and novel risk factors for ICH, stratified by ICH location and racial/ethnic group.

Design, Setting, and Participants

The Ethnic/Racial Variations of Intracerebral Hemorrhage Study was a case-control study of ICH among 3000 Black, Hispanic, and White individuals who experienced spontaneous ICH (1000 cases in each group). Recruitment was conducted between September 2009 and July 2016 at 19 US sites comprising 42 hospitals. Control participants were identified through random digit dialing and were matched to case participants by age (±5 years), sex, race/ethnicity, and geographic area. Data analyses were conducted from January 2019 to May 2020.

Main Outcomes and Measures

Case and control participants underwent a standardized interview, physical measurement for body mass index, and genotyping for the ɛ2 and ɛ4 alleles of APOE, the gene encoding apolipoprotein E. Prevalence, multivariable adjusted odds ratio (OR), and PAR percentage were calculated for each risk factor in the entire ICH population and stratified by racial/ethnic group and by lobar or nonlobar location.

Results

There were 1000 Black patients (median [interquartile range (IQR)] age, 57 [50-65] years, 425 [42.5%] women), 1000 Hispanic patients (median [IQR] age, 58 [49-69] years; 373 [37.3%] women), and 1000 White patients (median [IQR] age, 71 [59-80] years; 437 [43.7%] women). The mean (SD) age of patients with ICH was significantly lower among Black and Hispanic patients compared with White patients (eg, lobar ICH: Black, 62.2 [15.2] years; Hispanic, 62.5 [15.7] years; White, 71.0 [13.3] years). More than half of all ICH in Black and Hispanic patients was associated with treated or untreated hypertension (PAR for treated hypertension, Black patients: 53.6%; 95% CI, 46.4%-59.8%; Hispanic patients: 46.5%; 95% CI, 40.6%-51.8%; untreated hypertension, Black patients: 45.5%; 95% CI, 39.%-51.1%; Hispanic patients: 42.7%; 95% CI, 37.6%-47.3%). Lack of health insurance also had a disproportionate association with the PAR percentage for ICH in Black and Hispanic patients (Black patients: 21.7%; 95% CI, 17.5%-25.7%; Hispanic patients: 30.2%; 95% CI, 26.1%-34.1%; White patients: 5.8%; 95% CI, 3.3%-8.2%). A high sleep apnea risk score was associated with both lobar (OR, 1.68; 95% CI, 1.36-2.06) and nonlobar (OR, 1.62; 95% CI, 1.37-1.91) ICH, and high cholesterol was inversely associated only with nonlobar ICH (OR, 0.60; 95% CI, 0.52-0.70); both had no interactions with race and ethnicity. In contrast to the association between the ɛ2 and ɛ4 alleles of APOE and ICH in White individuals (eg, presence of APOE ɛ2 allele: OR, 1.84; 95% CI, 1.34-2.52), APOE alleles were not associated with lobar ICH among Black or Hispanic individuals.

Conclusions and Relevance

This study found sleep apnea as a novel risk factor for ICH. The results suggest a strong contribution from inadequately treated hypertension and lack of health insurance to the disproportionate burden and earlier onset of ICH in Black and Hispanic populations. These findings emphasize the importance of addressing modifiable risk factors and the social determinants of health to reduce health disparities.

State-level prevalence, health service use, and spending vary widely among Medicare beneficiaries with Parkinson disease

State-level variations in disease, healthcare utilization, and spending influence healthcare planning at federal and state levels and should be examined to understand national disparities in health outcomes. This descriptive study examined state-level variations in Parkinson disease (PD) prevalence, patient characteristics, Medicare spending, out-of-pocket costs, and health service utilization using data on 27.5 million Medicare beneficiaries in the US in 2014. We found that 45.8% (n = 179,496) of Medicare beneficiaries diagnosed with PD were women; 26.1% (n = 102,205) were aged 85+. The District of Columbia, New York, Illinois, Connecticut, and Florida had the highest age-, race-, and sex-adjusted prevalence of Parkinson disease among Medicare beneficiaries in the US. Women comprised over 48.5% of PD patient populations in West Virginia, Kentucky, Mississippi, Louisiana, and Arkansas. More than 31% of the PD populations in Connecticut, Pennsylvania, Hawaii, and Rhode Island were aged 85+. PD patients who were "dual-eligible"-receiving both Medicare and Medicaid benefits-also varied by state, from <10% to >25%. Hospitalizations varied from 304 to 653 stays per 1000 PD patients and accounted for 26.5% of the 7.9 billion United States Dollars (USD) paid by the Medicare program for healthcare services delivered to our sample. A diagnosis of PD was associated with greater healthcare use and spending. This study provides initial evidence of substantial geographic variation in PD patient characteristics, health service use, and spending. Further study is necessary to inform the development of state- and federal-level health policies that are cost-efficient and support desired outcomes for PD patients.

Temporal Trends in the Outcomes of Dialysis Patients Admitted With Acute Ischemic Stroke

BACKGROUND

There is a paucity of contemporary data on the characteristics and outcomes of acute ischemic stroke (AIS) in patients on maintenance dialysis.

METHODS AND RESULTS

We used the nationwide inpatient sample to examine contemporary trends in the incidence, management patterns, and outcomes of AIS in dialysis patients. A total of 930 010 patients were admitted with AIS between 2003 and 2014, of whom 13 642 (1.5%) were on dialysis. Overall, the incidence of AIS among dialysis patients decreased significantly (Ptrend<0.001), while it remained stable in non-dialysis patients (Ptrend=0.78). Compared with non-dialysis patients, those on dialysis were younger (67±13 years versus 71±15 years, P<0.001), and had higher prevalence of major comorbidities. Black patients constituted 35.2% of dialysis patients admitted with AIS compared with 16.7% of patients in the non-dialysis group (P<0.001). After propensity score matching, in-hospital mortality was higher in the dialysis group (7.6% versus 5.2%, P<0.001), but this mortality gap narrowed overtime (Ptrend<0.001). Hemorrhagic conversion and gastrointestinal bleeding rates were similar, but blood transfusion was more common in the dialysis group. Rates of severe disability surrogates (tracheostomy, gastrostomy, mechanical ventilation and non-home discharge) were also similar in both groups. However, dialysis patients had longer hospitalizations, and accrued a 25% higher total cost of acute care.

CONCLUSIONS

Dialysis patients have 8-folds higher incidence of AIS compared withnon-dialysis patients. They also have higher risk-adjusted in-hospital mortality, sepsis and blood transfusion, longer hospitalizations, and higher cost. There is a need to identify preventative strategies to reduce the risk of AIS in the dialysis population.

A clinical trial design using the concept of proportional time using the generalized gamma ratio distribution

Traditional methods of sample size and power calculations in clinical trials with a time-to-event end point are based on the logrank test (and its variations), Cox proportional hazards (PH) assumption, or comparison of means of 2 exponential distributions. Of these, sample size calculation based on PH assumption is likely the most common and allows adjusting for the effect of one or more covariates. However, when designing a trial, there are situations when the assumption of PH may not be appropriate. Additionally, when it is known that there is a rapid decline in the survival curve for a control group, such as from previously conducted observational studies, a design based on the PH assumption may confer only a minor statistical improvement for the treatment group that is neither clinically nor practically meaningful. For such scenarios, a clinical trial design that focuses on improvement in patient longevity is proposed, based on the concept of proportional time using the generalized gamma ratio distribution. Simulations are conducted to evaluate the performance of the proportional time method and to identify the situations in which such a design will be beneficial as compared to the standard design using a PH assumption, piecewise exponential hazards assumption, and specific cases of a cure rate model. A practical example in which hemorrhagic stroke patients are randomized to 1 of 2 arms in a putative clinical trial demonstrates the usefulness of this approach by drastically reducing the number of patients needed for study enrollment.

Association of multiple ischemic strokes with mortality in incident hemodialysis patients: an application of multistate model to determine transition probabilities in a retrospective observational cohort

Background

Little is known about the effect of multiple, or subsequent, ischemic strokes in patients receiving hemodialysis.

Methods

We undertook a retrospective cohort study of incident hemodialysis patients with Medicare coverage who had experienced a first ischemic stroke. Factors associated with either a subsequent ischemic stroke or death following a first new stroke were modeled. A multistate model with Cox proportional hazards was used to predict transition probabilities from first ischemic stroke to either subsequent stroke or to death, and the demographic and clinical factors associated with the respective transition probabilities were determined. Effect of a subsequent ischemic stroke on survival was quantified.

Results

Overall, 12,054 individuals (mean age 69.7 years, 41.3 % male, 53.0 % Caucasian and 34.0 % African-American) experienced a first new ischemic stroke. Female sex was associated with an increased risk of having a subsequent ischemic stroke (adjusted hazard ratio 1.37, 95 % confidence intervals 1.20 – 1.56, P < 0.0001); African-Americans, as compared to Caucasians, had lower likelihood of dying after a first new ischemic stroke (0.81, 0.77 – 0.85, P < 0.0001). A subsequent stroke trended towards having a higher likelihood of transitioning to death compared to a first new ischemic stroke on dialysis (1.72, 0.96 – 3.09, P = 0.071). When a subsequent ischemic stroke occurs at 24 months, probability of survival dropped >15 %, in absolute terms, from 0.254 to 0.096, with substantial drops observed at subsequent time points such that the probability of survival was more than halved.

Conclusions

Likelihood of subsequent ischemic stroke and of survival in hemodialysis patients appears to vary by sex and race: females are more likely than males to experience a subsequent ischemic stroke, and Caucasians are more likely than African-Americans to die after a first new ischemic stroke. The risk of a transitioning to a subsequent stroke (after having had a first) increases until about 1 year, then decreases. Subsequent strokes are associated with decreased probability of survival, an effect which increases as time since first stroke elapses. This information may be of assistance to clinicians when counseling hemodialysis patients about the implications of recurrent ischemic stroke.

Geovariation in Fracture Risk among Patients Receiving Hemodialysis

BACKGROUND AND OBJECTIVES

Fractures are a major source of morbidity and mortality in patients receiving dialysis. We sought to determine whether rates of fractures and tendon ruptures vary geographically.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the US Renal Data System were used to create four yearly cohorts, 2007-2010, including all eligible prevalent patients on hemodialysis in the United States on January 1 of each year. A secondary analysis comprising patients in a large dialysis organization conducted over the same period permitted inclusion of patient-level markers of mineral metabolism. Patients were grouped into 10 regions designated by the Centers for Medicare and Medicaid Services and divided by latitude into one of three bands: south, <35°; middle, 35° to <40°; and north, ≥40°. Poisson regression was used to calculate unadjusted and adjusted region-level rate ratios for events.

RESULTS

Overall, 327,615 patients on hemodialysis were included. Mean (SD) age was 61.8 (15.0) years old, 52.7% were white, and 55.0% were men. During 716,962 person-years of follow-up, 44,014 fractures and tendon ruptures occurred, the latter being only 0.3% of overall events. Event rates ranged from 5.36 to 7.83 per 100 person-years, a 1.5-fold rate difference across regions. Unadjusted region-level rate ratios varied from 0.83 (95% confidence interval, 0.81 to 0.85) to 1.20 (95% confidence interval, 1.18 to 1.23), a 1.45-fold rate difference. After adjustment for a wide range of case mix variables, a 1.33-fold variation in rates remained. Rates were higher in north and middle bands than the south (north rate ratio, 1.18; 95% confidence interval, 1.13 to 1.23; middle rate ratio, 1.13; 95% confidence interval, 1.10 to 1.17). Latitude explained 11% of variation, independent of region. A complementary analysis of 87,013 patients from a large dialysis organization further adjusted for circulating mineral metabolic parameters and protein energy wasting yielded similar results.

CONCLUSIONS

Rates of fractures vary geographically in the United States dialysis population, even after adjustment for known patient characteristics. Latitude seems to contribute to this phenomenon, but additional analyses exploring whether other factors might influence variation are warranted.

Efficacy and safety of warfarin in dialysis patients with atrial fibrillation: a systematic review and meta-analysis

Objective

To systematically review and meta-analyse the risk–benefit ratio of warfarin users compared with non-warfarin users in patients with atrial fibrillation (AF), who are undergoing dialysis.

Methods

We searched PubMed/MEDLINE, EMBASE, SCOPUS, Web of Science, Cochrane Library, grey literature, conference proceedings, trial registrations and also did handsearch. Cohort studies without language restrictions were included. Two investigators independently conducted a full abstraction of data, risk of bias and graded evidence. Effect estimates were pooled using random-effect models.

Main outcome measure

All-cause mortality, total stroke/thromboembolism and bleeding complications.

Results

14 studies included 37 349 dialysis patients with AF, of whom 12 529 (33.5%) were warfarin users. For all-cause mortality: adjusted HR=0.99 (95% CI 0.89 to 1.10; p=0.825), unadjusted risk ratio (RR)=1.00 (95% CI 0.96 to 1.04; p=0.847). For stroke/thromboembolism: adjusted HR=1.06 (95% CI 0.82 to 1.36; p=0.676), unadjusted incidence rate ratio (IRR)=1.23 (95% CI 0.94 to 1.61; p=0.133). For ischaemic stroke/transient ischaemic attack, adjusted HR=0.91 (95% CI 0.57 to 1.45; p=0.698), unadjusted IRR=1.16 (95% CI 0.84 to 1.62; p=0.370). For haemorrhagic stroke, adjusted HR=1.60 (95% CI 0.91 to 2.81; p=0.100), unadjusted IRR=1.48 (95% CI 0.92 to 2.36; p=0.102). Major bleeding was increased among warfarin users; adjusted HR=1.35 (95% CI 1.11 to 1.64; p=0.003) and unadjusted IRR=1.22 (95% CI 1.07 to 1.40; p=0.003).

Conclusions

Among dialysis patients with AF, warfarin therapy was not associated with mortality and stroke/thromboembolism, but significantly increased the risk of major bleeding. More rigorous studies are essential to demonstrate the effect of warfarin for stroke prophylaxis in dialysis patients with AF.

Variation in Care for Patients with Irritable Bowel Syndrome in the United States

Objectives

Irritable bowel syndrome (IBS) affects nearly one in seven Americans. Significant national variations in care may exist, due to a current lack of standardized diagnosis and treatment algorithms; this can translate into a substantial additional economic burden. The study examines healthcare resource utilization in patients with IBS and in the subset of IBS patients with constipation (IBS-C) and analyzes the variation of IBS care for these patients across the United States (US).

Methods

Healthcare resource use (HRU), including gastrointestinal (GI) procedures and tests, all-cause and intestinal-related medical visits, GI specialist visits, and constipation or diarrhea pharmacy prescriptions for IBS patients enrolled in a large US administrative claims database (2001–2012) were analyzed for the 24-month period surrounding first diagnosis. Multivariate regression models, adjusting for age, gender, year of first diagnosis, insurance type, and Charlson comorbidity index, compared HRU across states (each state vs. the average of all other states).

Results

Of 201,322 IBS patients included, 77.2% were female. Mean age was 49.4 years. One in three patients had ≥3 distinct GI medical procedures or diagnostic tests; 50.1% visited a GI specialist. Significant HRU differences were observed in individual states compared to the national average. IBS-C patients had more medical visits, procedures, and pharmacy prescriptions for constipation/diarrhea than IBS patients without constipation.

Conclusions

This study is the first to identify considerable regional variations in IBS healthcare across the US and to note a markedly higher HRU by IBS-C patients than by IBS patients without constipation. Identifying the reasons for these variations may improve quality of care and reduce the economic burden of IBS.

An ensemble survival model for estimating relative residual longevity following stroke: Application to mortality data in the chronic dialysis population

Time-dependent covariates can be modeled within the Cox regression framework and can allow both proportional and nonproportional hazards for the risk factor of research interest. However, in many areas of health services research, interest centers on being able to estimate residual longevity after the occurrence of a particular event such as stroke. The survival trajectory of patients experiencing a stroke can be potentially influenced by stroke type (hemorrhagic or ischemic), time of the stroke (relative to time zero), time since the stroke occurred, or a combination of these factors. In such situations, researchers are more interested in estimating lifetime lost due to stroke rather than merely estimating the relative hazard due to stroke. To achieve this, we propose an ensemble approach using the generalized gamma distribution by means of a semi-Markov type model with an additive hazards extension. Our modeling framework allows stroke as a time-dependent covariate to affect all three parameters (location, scale, and shape) of the generalized gamma distribution. Using the concept of relative times, we answer the research question by estimating residual life lost due to ischemic and hemorrhagic stroke in the chronic dialysis population.

Risk Factors of Ischemic Stroke and Subsequent Outcome in Patients Receiving Hemodialysis

Background and Purpose—

End-stage renal disease (ESRD) requiring hemodialysis carries up to a 10-fold greater risk of stroke than normal renal function. Knowledge on risk factors and management strategies derived from the general population may not be applicable to those with ESRD. We studied a large ESRD population to identify risk factors and outcomes for stroke.

Methods—

All adult patients receiving hemodialysis for ESRD from January 1, 2007, to December 31, 2012, were extracted from the electronic patient record. Variables associated with stroke were identified by survival analysis; demographic, clinical, imaging, and dialysis-related variables were assessed, and case-fatality was determined. Follow-up was until December 31, 2013.

Results—

A total of 1382 patients were identified (mean age, 60.5 years; 58.5% men). The prevalence of atrial fibrillation was 21.2%, and 59.4% were incident hemodialysis patients. One hundred and sixty patients (11.6%) experienced a stroke during 3471 patient-years of follow-up (95% ischemic). Stroke incidence was 41.5/1000 patient-years in prevalent and 50.1/1000 patient-years in incident hemodialysis patients. Factors associated with stroke on regression analysis were prior stroke, diabetes mellitus, and age at starting renal replacement therapy. Atrial fibrillation was not significantly associated with stroke, and warfarin did not affect stroke risk in warfarin-treated patients. Fatality was 18.8% at 7 days, 26.9% at 28 days, and 56.3% at 365 days after stroke.

Conclusions—

Incidence of stroke is high in patients with ESRD on hemodialysis with high case-fatality. Incident hemodialysis patients had the highest stroke incidence. Many, but not all, important risk factors commonly associated with stroke in the general population were not associated with stroke in patients receiving hemodialysis.

Stroke-free status and depression scores among Saudi dialysis patients

BACKGROUND

To assess the prevalence of stroke symptoms and depression among Saudi dialysis patients and related factors.

METHODS

This is a cross-sectional multicentre study of Saudi dialysis patients. Demographics, clinical and laboratory's data were collected. Freedom from stroke symptoms was assessed using the Questionnaire for Verifying Stroke-Free Status and depression using the Geriatric Depression Scale.

RESULTS

Five-hundred and forty-nine patients (77.3% response rate); 94.6% were receiving hemodialysis and 5.4% peritoneal dialysis were included in the study. Freedom from stroke was reported in 76.6% of patients, was higher in females (p = 0.07), and was not affected by the presence of diabetes mellitus coronary artery disease or peripheral vascular disease. However, it was significantly lower in hypertensive patients (p = 0.035) and was not affected by age, dialysis duration, Kt/V, albumin or hemoglobin levels. It was, however, more prevalent in the non-depressed patients compared to depressed patients (p = 0.036). Mild and major depression scores were noted in 45.2% and 6.1%, respectively; the depression score being significantly higher in HD than in PD patients (6.3 ± 3.4 vs. 5.0 ± 3.2 p = 0.049) but was not related to sex, employment, vascular access type, age, dialysis duration, Kt/V or serum albumin or hemoglobin levels.

CONCLUSION

A quarter of the patients were not stroke symptom-free and these were more likely the depressed patients, in females, but significantly less in hypertensive patients. Almost half of the patients were depressed with 6.1% having major depression. The depression score was significantly higher in HD than in PD patients.

Access to Speech-Language Pathology Services for African-American Clients with Aphasia: A Qualitative Study

The purpose of this article is to report the perceptions and experiences of family members of five African-American clients with aphasia as they accessed speech-language pathology services. Client or family responses to a survey and during a semi-structured, ethnographic interview revealed information on barriers and facilitators influencing access to speech therapy services. These data are part of a larger investigation into cultural and linguistic barriers that might influence racial and/or ethnic minority clients’ awareness of, access to, and utilization of speech-language pathology services. Results reveal the presence of distinct barriers and facilitators that can influence timely, sustained access to speech-language pathology services for African-American clients and their families. These data have critical implications for speech-language pathologists (SLPs), audiologists, and all healthcare providers.