Validation of Stroke Diagnosis in the National Registry of Hospitalized Patients in the Czech Republic

Diagnostic accuracy and radiological validation of intracerebral hemorrhage diagnosis in the Swedish Stroke Register (Riksstroke)

BACKGROUND AND PURPOSE

National quality registries for stroke care operate under the assumption that the included patients are correctly diagnosed. We aimed to validate the clinical diagnosis of spontaneous intracerebral hemorrhage (ICH) in Riksstroke (RS) by evaluating radiological data from a large, unselected ICH population.

METHODS

We conducted a retrospective, multicenter study including all ICH patients registered in RS between 2016 and 2020 residing in Skåne County in Sweden (1.41 million inhabitants). Radiological data from first imaging were evaluated for the presence of spontaneous ICH. Other types of bleeds were registered if a spontaneous ICH was not identified on imaging. The radiological evaluation was independently performed by one radiology fellow and one senior neuroradiologist.

RESULTS

Between 2016 and 2020, 1784 ICH cases were registered in RS, of which 1655 (92.8%) had a radiological diagnosis consistent with spontaneous ICH. In the 129 (7.2%) remaining cases, the radiological diagnosis was instead traumatic bleed (n = 80), subarachnoid hemorrhage (n = 15), brain tumor bleed (n = 14), ischemic lesion with hemorrhagic transformation (n = 14), ischemic lesion (n = 3), or no bleed at all (n = 3). There was a higher degree of incorrect coding in the older age groups.

CONCLUSION

At radiological evaluation, 92.8% of ICH diagnoses in RS were consistent with spontaneous ICH, yielding a high rate of agreement that strengthens the validity of the diagnostic accuracy in the register, justifying the use of high coverage quality register data for epidemiological purposes. The most common coding error was traumatic bleeds that were classified as spontaneous ICH.

Exploring dual diagnosis in opioid agonist treatment patients: a registry-linkage study in Czechia and Norway

BACKGROUND

Knowledge of co-occurring mental disorders (termed 'dual diagnosis') among patients receiving opioid agonist treatment (OAT) is scarce. This study aimed (1) to estimate the prevalence and structure of dual diagnoses in two national cohorts of OAT patients and (2) to compare mental disorders between OAT patients and the general populations stratified on sex and standardized by age.

METHODS

A registry-linkage study of OAT patients from Czechia (N = 4,280) and Norway (N = 11,389) during 2010-2019 was conducted. Data on mental disorders (F00-F99; ICD-10) recorded in nationwide health registers were linked to the individuals registered in OAT. Dual diagnoses were defined as any mental disorder excluding substance use disorders (SUDs, F10-F19; ICD-10). Sex-specific age-standardized morbidity ratios (SMR) were calculated for 2019 to compare OAT patients and the general populations.

RESULTS

The prevalence of dual diagnosis was 57.3% for Czechia and 78.3% for Norway. In Czechia, anxiety (31.1%) and personality disorders (25.7%) were the most prevalent, whereas anxiety (33.8%) and depression (20.8%) were the most prevalent in Norway. Large country-specific variations were observed, e.g., in ADHD (0.5% in Czechia, 15.8% in Norway), implying differences in screening and diagnostic practices. The SMR estimates for any mental disorders were 3.1 (females) and 5.1 (males) in Czechia and 5.6 (females) and 8.2 (males) in Norway. OAT females had a significantly higher prevalence of co-occurring mental disorders, whereas SMRs were higher in OAT males. In addition to opioid use disorder (OUD), other substance use disorders (SUDs) were frequently recorded in both countries.

CONCLUSIONS

Results indicate an excess of mental health problems in OAT patients compared to the general population of the same sex and age in both countries, requiring appropriate clinical attention. Country-specific differences may stem from variations in diagnostics and care, reporting to registers, OAT provision, or substance use patterns.

Validation of ICD-10 hospital discharge diagnosis codes to identify incident and recurrent ischemic stroke from a US integrated healthcare system

PURPOSE

This study validated incident and recurrent ischemic stroke identified by International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10) hospital discharge diagnosis codes.

METHODS

Using electronic health records (EHR) of adults (≥18 years) receiving care from Kaiser Permanente Southern California with ICD-10 hospital discharge diagnosis codes of ischemic stroke (I63.x, G46.3, and G46.4) between October 2015 and September 2020, we identified 75 patients with both incident and recurrent stroke events (total 150 cases). Two neurologists independently evaluated validity of ICD-10 codes through chart reviews.

RESULTS

The positive predictive value (PPV, 95% CI) for incident stroke was 93% (95% CI: 88%, 99%) and the PPV for recurrent stroke was 72% (95% CI: 62%, 82%). The PPV for recurrent stroke improved after applying a gap of 20 days (PPV of 75%; 95% CI: 63%, 87%) or removing hospital admissions related to stroke-related procedures (PPV of 78%; 95% CI: 68%, 88%).

CONCLUSION

The ICD-10 hospital discharge diagnosis codes for ischemic stroke showed a high PPV for incident cases, while the PPV for recurrent cases were less optimal. Algorithms to improve the accuracy of ICD-10 codes for recurrent ischemic stroke may be necessary.

Patterns and Outcomes of Intensive Care on Acute Ischemic Stroke Patients in the US

BACKGROUND

Up to 20% of acute ischemic stroke (AIS) patients may benefit from intensive care unit (ICU)-level care; however, there are few studies evaluating ICU availability for AIS. We aim to summarize the proportion of elderly AIS patients in the United States who are admitted to an ICU and assess the national availability of ICU-level care in AIS.

METHODS

We performed a retrospective cohort study using de-identified Medicare inpatient datasets from January 1, 2016 through December 31, 2019 for US individuals aged ≥65 years. We used validated International Classification of Diseases, Tenth Revision, Clinical Modification codes to identify AIS admission and interventions. ICU-level care was identified by revenue center code. AIS patient characteristics and interventions were stratified by receipt of ICU-level care, comparing differences through calculated standardized mean difference score due to large sample sizes.

RESULTS

From 2016 through 2019, a total of 952 400 admissions by 850 055 individuals met criteria for hospital admission for AIS with 19.9% involving ICU-level care. Individuals were predominantly >75 years of age (58.5%) and identified as white (80.0%). Hospitals on average admitted 11.4% (SD 14.6) of AIS patients to the ICU, with the median hospital admitting 7.7% of AIS patients to the ICU. The ICU admissions were younger and more likely to receive reperfusion therapy but had more comorbid conditions and neurologic complications. Of the 5084 hospitals included, 1971 (38.8%) reported no ICU-level AIS care. Teaching hospitals (36.9% versus 1.6%, P<0.0001) with larger AIS volume (P<0.0001) or in larger metropolitan areas (P<0.0001) were more likely to have an ICU available.

CONCLUSIONS

We found evidence of national variation in the availability of ICU-level care for AIS admissions. Since ICUs may provide comprehensive care for the most severe AIS patients, continued effort is needed to examine ICU accessibility and utility among AIS.

Reconstruction of pseudonymized patient-trajectories in Austria's stroke cohort using medical record-linkage of in-patient routine documentation to establish a nation-wide acute stroke cohort of 102,107 pseudonymized patients between 2015 and 2019

INTRODUCTION

Administrative health data are increasingly used for disease surveillance, quality assurance and research purposes. In Austria, reporting of a standardized dataset is mandatory for each patient.

PATIENTS AND METHODS

Routine documentation includes administrative and medical data, including admission and discharge characteristics, disease-diagnosis using ICD-10, medical procedure codes, and coding of involved hospital departments. Since 2015, a three-step pseudonymization on these data is provided including a pseudonym using secure hash algorithm 256, a non-recalculable record-ID, and age-groups of 5 years, allowing the reconstruction of individual patient-trajectories. We included persons aged ⩾20 years with an in-patient treatment in Austrian hospitals for acute stroke or transient ischemic attack (TIA) between 01.01.2015 and 31.12.2019 using medical record-linkage.

RESULTS

This totals 102,107 patients (49.3% women) with 107,055 treatment episodes. An ischemic stroke (IS) occurred in 60.9% (n = 65,133), 27.1% (n = 29,019) had a TIA, 3.3% (n = 3488) a subarachnoid hemorrhage, and 8.8% (n = 9415) an intracerebral hemorrhage (ICH). The study period covers 35.2 million person-years at risk, with a hospitalization rate for acute stroke of 221.8 per 100,000 person-years (95% CI 220.2-223.3), and 185.1 per 100,000 person-years (95% CI 183.7-186.5) for IS. Unscheduled re-admissions within 1 year occurred in 29.2% (95% CI 28.8-29.7) after IS, and 41.7% (95% CI 40.0-43.3) after ICH. Recurrent stroke occurred in 5.3% (95% CI 5.1-5.5) after IS, and 5.6% (95% CI 4.9-6.4) after ICH.

DISCUSSION

We present herein the details of a novel methodology to establish a nation-wide unselected Austrian stroke cohort, and to reconstruct pseudonymized individual longitudinal patient-trajectories on a national level. This approach shows potential applications in epidemiological research, quality assessment and outcome measurement.

CONCLUSION

This novel approach opens new research fields, facilitates international comparison, and is needed for national benchmarking to assess the achievement of goals according to the Stroke Action Plan for Europe and augment the quality of Austria's integrated stroke care.

Are total omega-3 and omega-6 polyunsaturated fatty acids predictors of fatal stroke in the Adventist Health Study 2 prospective cohort?

Introduction

The effects of omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFA) on cerebrovascular disease remain unsettled. However, most studies have focused on marine sourced n-3 PUFA rather than total n-3 PUFA, of which the majority in the American diet is plant derived. This study therefore intended to investigate these effects in a cohort for which the vegetarian diet was more prevalent than the general public.

Methods

Cox proportional hazards with fatal stroke as the outcome was performed on the approximately 96,000 subject Adventist Health Study 2 prospective cohort. Stratification by race and sex was performed on models with a priori covariables, comparing 90^th to 10^th percentile daily intakes of energy-adjusted total n-3 PUFA, total n-6 PUFA, and the n-6 / n-3 PUFA ratio as variables of interest.

Results

For the main analytical group (78,335 subjects), the hazard ratio (95% confidence interval) for total n-3 PUFA was 0.65 (0.51–0.83), and for total n-6 PUFA was 1.37 (1.02–1.82), while adjusting for both fatty acids in the model. The n-6 / n-3 PUFA ratio was harmful with a HR of 1.40 (1.16–1.69), whereas the inclusion of total n-3 PUFA slightly attenuated the HR to 1.33(1.02–1.74). Effects were similar for the non-black sex-combined and sex-specific analyses.

Conclusion

In most analytic groups, subjects with greater total n-3 PUFA intakes have lower risk of fatal stroke, and those with a higher n-6 / n-3 PUFA ratio had higher risk. However, the n-6 / n-3 PUFA ratio remains statistically significant even after adjusting for total n-3 PUFA or total n-6 PUFA, suggesting that the ratio is of epidemiologic interest for cerebrovascular disease research.

Trends in surgical procedures for spontaneous intracerebral hemorrhage in Japan

OBJECTIVES

Minimally invasive surgery for spontaneous intracerebral hemorrhage (ICH) has become increasingly popular in recent years. However, there are no reports on the recent trends in surgical procedures for spontaneous ICH. To investigate current trends in surgical methods for spontaneous ICH using a nationwide inpatient database from Japan.

MATERIALS AND METHODS

Patients who underwent surgery for spontaneous ICH between April 2014 and March 2018 were identified in a nationwide inpatient database from Japan. We examined patient characteristics, diagnoses, types of surgery, complications, and discharge status.

RESULTS

We identified 21,129 inpatients who underwent surgery for spontaneous ICH. The procedures were as follows: 16,256 (76.9%) transcranial hemorrhage evacuations, 3722 (17.6%) endoscopic hemorrhage evacuations, and 1151 (5.4%) stereotactic aspirations of hemorrhage. Patients tended to receive transcranial hemorrhage evacuations in hospitals with fewer surgical cases. The proportions of endoscopic hemorrhage evacuations increased annually, whereas those of stereotactic surgery decreased. The proportions of transcranial surgery remained almost unchanged. Tracheostomy and hospitalization costs were lower in the stereotactic aspirations of hemorrhage group, and the proportions of reoperation were higher in the endoscopic hemorrhage evacuations group.

CONCLUSIONS

The use of endoscopic surgery for spontaneous ICH has increased in Japan. This study can form the basis of future clinical investigations into spontaneous ICH surgery.

Predictors of Short- and Long-Term Mortality in Ischemic Stroke: A Community-Based Study in Brno, Czech Republic

BACKGROUND AND OBJECTIVE

Short- and long-term mortality following ischemic stroke (IS) and their predictors have not been defined in the Czech population, and studies on long-term mortality are largely missing for the populations of Central Europe.

METHODS

Using the National Register of Hospitalized Patients and the Czech National Mortality Registry, we analyzed data on 1-month, 1-year, and 3-year all-cause mortality for patients admitted with IS to any of the 4 hospitals with a certified stroke unit in Brno, Czech Republic, in 2011. We reviewed discharge summaries and recorded potential factors impacting mortality after the index stroke event. Using univariate and multivariable analyses, we identified predictors of mortality at all 3 time points.

RESULTS

In our multivariable model, statin use (odds ratio [OR] 0.095, p < 0.0001), age at stroke (OR 1.03, p = 0.0445), and admission National Institutes of Health Stroke Scale (NIHSS) score (OR 1.16, p < 0.0001) predicted 1-month mortality, while statin use (OR 0.43, p = 0.0004), history of cardiac failure (OR 2.17, p = 0.0137), age at stroke (OR 1.07, p < 0.0001), and admission NIHSS score (OR 1.14, p < 0.0001) predicted 1-year mortality. Statin use (OR 0.54, p = 0.0051), history of cardiac failure (OR 2.13, p = 0.0206), age at stroke (OR 1.07, p < 0.0001), and admission NIHSS score (OR 1.11, p < 0.0001) also predicted 3-year mortality.

CONCLUSIONS

Our study is the first to report data on short- and long-term mortality rates and their predictors in patients hospitalized with IS in the Czech population. Our results indicate that mortality rates and predictors of mortality are consistent with those reported in studies from other populations throughout the world.

Incidence and Outcomes of Hemorrhagic Stroke among Adults in Spain (2016-2018) According to Sex: A Retrospective, Cohort, Observational, Propensity Score Matched Study

(1) Background: We aim to analyze sex differences in the incidence, clinical characteristics and in-hospital outcomes of hemorrhagic stroke (HS) in Spain (2016–2018) using the National Hospital Discharge Database. (2) Methods: Retrospective, cohort, observational study. We estimated the incidence of HS in men and women. We analyzed comorbidity, treatments, procedures, and hospital outcomes. We matched each woman with a man by age, type of HS and medical conditions using propensity score matching. (3) Results: HS was coded in 57,227 patients aged ≥18 years (44.3% women). Overall, men showed higher incidence rates (57.3/10⁵ vs. 43.0/10⁵; p < 0.001; IRR = 1.60; 95% CI: 1.38–1.83). Women suffered more subarachnoid hemorrhages (25.2% vs. 14.6%), whereas men more often had intracerebral hemorrhages (55.7% vs. 54.1%). In-hospital mortality (IHM) was higher for intracerebral hemorrhage in both men and women. Women underwent decompressive craniectomy less often than men (5.0% vs. 6.2%; p < 0.001). After matching, IHM among women was higher (29.0% vs. 23.7%; p < 0.001). Increments in age, comorbidity and use of anticoagulants and antiplatelet agents prior to hospitalization were associated were higher IHM, and decompressive craniectomy was associated with lower IHM in both sexes. After multivariable adjustment, women had higher IHM (OR = 1.23; 95% CI: 1.18–1.28). (4) Conclusion: Men had higher incidence rates of HS than women. Women less often underwent decompressive craniectomy. IHM was higher among women admitted for HS than among men.

RD, Bryndziar T, Jarkovsky J, Tomek A, Sramek M, Skoda O, Sramkova T, Littnerova S, Mikulik R. Treat COVID-19, but Not Only COVID-19: Stroke Matters as Well

INTRODUCTION

During the COVID-19 pandemic, studies reported less number of hospitalizations for acute stroke and reduction in the use of recanalization treatments. This study analyzes nationwide data on stroke admissions and management in the Czech Republic during the first wave of the COVID-19 pandemic.

METHODS

We compared the early COVID-19 pandemic (March-May 2020) with the pre-pandemic period (January-February 2020 and March-May 2019): (a) the National Register of Reimbursed Health Services provided volume of all admissions for subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), and ischemic stroke (IS), and volume of recanalization treatments (intravenous thrombolysis [IVT] and mechanical thrombectomy [MT]); (b) Registry of Stroke Care Quality provided door-to-needle time (DNT), onset-to-door time (ODT), and stroke severity at admission (National Institutes of Health Stroke Scale, NIHSS) for IS.

RESULTS

During the pandemic (March-May 2020), the peak number of COVID-19 patients treated in Czech hospitals was 39 per million. In March-May 2020 versus March-May 2019, hospital admissions decreased as follows: stroke overall by 14% (p < 0.001), IS by 14% (p < 0.001), SAH by 15% (p = 0.07), and ICH by 7% (p = 0.17). The mean age was 74 years versus 74 years (p = 0.33), and 52% versus 51% were men (p = 0.34). The volumes of IVT and MT decreased by 14% (p = 0.001) and 19% (p = 0.01), respectively. The proportions of all IS patients receiving IVT or MT remained unchanged, with, respectively, 17% versus 17% receiving IVT (p = 0.86) and 5% versus 5% receiving MT (p = 0.48). DNT and ODT were 24 versus 25 min (p = 0.58) and 168 versus 156 min (p = 0.23), respectively. NIHSS at admission did not differ (6 vs. 6; p = 0.54).

CONCLUSION

Even with a low burden of COVID-19 during the first wave and no change in organization and logistics of stroke services, stroke admissions and volume of recanalization treatments decreased. Public health communication campaigns should encourage people to seek emergency medical care for stroke symptoms during the COVID-19 pandemic.

Sex-related disparities in the incidence and outcomes of hemorrhagic stroke among type 2 diabetes patients: a propensity score matching analysis using the Spanish National Hospital Discharge Database for the period 2016-18

Background

To analyze incidence, use of therapeutic procedures, use of oral anticoagulants (OACs) and antiplatelet agents prior to hospitalization, and in-hospital outcomes among patients who were hospitalized with hemorrhagic stroke (HS) according to the presence of type 2 diabetes mellitus (T2DM) in Spain (2016–2018) and to assess the role of sex differences among those with T2DM.

Methods

Using the Spanish National Hospital Discharge Database we estimated the incidence of HS hospitalizations in men and women aged ≥ 35 years with and without T2DM. Propensity score matching (PSM) was used to compare population subgroups according to sex and the presence of T2DM.

Results

HS was coded in 31,425 men and 24,975 women, of whom 11,915 (21.12%) had T2DM. The adjusted incidence of HS was significantly higher in patients with T2DM (both sexes) than in non-T2DM individuals (IRR 1.15; 95% CI 1.12–1.17). The incidence of HS was higher in men with T2DM than in T2DM women (adjusted IRR 1.60; 95% CI 1.57–1.63). After PSM, men and women with T2DM have significantly less frequently received decompressive craniectomy than those without T2DM. In-hospital mortality (IHM) was higher among T2DM women than matched non-T2DM women (32.89% vs 30.83%; p = 0.037), with no differences among men. Decompressive craniectomy was significantly more common in men than in matched women with T2DM (5.81% vs. 3.33%; p < 0.001). IHM was higher among T2DM women than T2DM men (32.89% vs. 28.28%; p < 0.001). After adjusting for confounders with multivariable logistic regression, women with T2DM had a 18% higher mortality risk than T2DM men (OR 1.18; 95% CI 1.07–1.29). Use of OACs and antiplatelet agents prior to hospitalization were associated to higher IHM in men and women with and without T2DM.

Conclusions

T2DM is associated with a higher incidence of HS and with less frequent use of decompressive craniectomy in both sexes, but with higher IHM only among women. Sex differences were detected in T2DM patients who had experienced HS, with higher incidence rates, more frequent decompressive craniectomy, and lower IHM in men than in women.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01334-2.

Systematic Review and Meta-Analysis of Diagnostic Agreement in Suspected TIA

Objective

To determine the interrater variability for TIA diagnostic agreement among expert clinicians (neurologists/stroke physicians), administrative data, and nonspecialists.

Methods

We performed a meta-analysis of studies from January 1984 to January 2019 using MEDLINE, EMBASE, and PubMed. Two reviewers independently screened for eligible studies and extracted interrater variability measurements using Cohen's kappa scores to assess diagnostic agreement.

Results

Nineteen original studies consisting of 19,421 patients were included. Expert clinicians demonstrate good agreement for TIA diagnosis (κ = 0.71, 95% confidence interval [CI] = 0.62-0.81). Interrater variability between clinicians' TIA diagnosis and administrative data also demonstrated good agreement (κ = 0.68, 95% CI = 0.62-0.74). There was moderate agreement (κ = 0.41, 95% CI = 0.22-0.61) between referring clinicians and clinicians at TIA clinics receiving the referrals. Sixty percent of 748 patient referrals to TIA clinics were TIA mimics.

Conclusions

Overall agreement between expert clinicians was good for TIA diagnosis, although variation still existed for a sizeable proportion of cases. Diagnostic agreement for TIA decreased among nonspecialists. The substantial number of patients being referred to TIA clinics with other (often neurologic) diagnoses was large, suggesting that clinicians, who are proficient in managing TIAs and their mimics, should run TIA clinics.

Validation of ICD-10-CM Diagnosis Codes for Identification of Patients with Acute Hemorrhagic Stroke in a National Health Insurance Claims Database

Purpose

The performance of the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes for identifying acute hemorrhagic stroke in Taiwan’s National Health Insurance claims database has not been assessed. This study aimed to construct and validate the case definitions for acute hemorrhagic stroke based on ICD-10-CM diagnostic codes.

Patients and Methods

From January 2018 to December 2019, all inpatient records with ICD-10-CM code of I60 or I61 in any field of the discharge diagnoses were retrieved from the hospitalization claims data and all hospitalizations with a final diagnosis of subarachnoid hemorrhage (SAH) or intracerebral hemorrhage (ICH) were identified from the stroke registry databases. The clinical diagnosis in the stroke registry was treated as the reference standard. For hospitalizations not recorded in the stroke registry, manual review of the medical records and images was done to ascertain the diagnosis. The positive predictive value (PPV) and sensitivity of various case definitions for acute hemorrhagic stroke were estimated.

Results

Among the 983 hospitalizations, 860, 111, and 12 were determined to be true-positive, false-positive, and false-negative episodes of acute hemorrhagic stroke, respectively. The PPV and sensitivity of the ICD-10-CM codes of I60 or I61 for identifying acute hemorrhagic stroke were 88.6% and 98.6%, respectively. The PPV increased to 98.2%, whereas the sensitivity decreased to 93.1% when acute hemorrhagic stroke was defined as hospitalizations in which the primary diagnosis field contained I60 or I61. Hemorrhagic transformation of ischemic stroke and concomitant cerebrovascular diseases other than SAH or ICH were the main reasons for a false-positive and false-negative diagnosis of acute hemorrhagic stroke, respectively.

Conclusion

This study demonstrated the performance of ICD-10-CM codes for identifying acute hemorrhagic stroke and may offer a reference for future claims-based stroke studies.

Incidence of Stroke and Ischemic Stroke Subtypes: A Community-Based Study in Brno, Czech Republic

BACKGROUND

There are few contemporary epidemiological data on stroke for Central Europe. We performed a population-based study evaluating the incidence of stroke, stroke types, and ischemic stroke (IS) subtypes in Brno, the second biggest city in the Czech Republic (CR).

METHODS

Using the National Registry of Hospitalized Patients, and hospital databases, we identified all patients hospitalized with a stroke diagnosis in Brno hospitals in 2011. For Brno residents with validated stroke diagnosis, we calculated (a) the overall incidence of hospitalized stroke, (b) incidence rates for IS, subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH), and (c) incidence rates for IS subtypes. We calculated the average annual age- and sex-standardized incidence (European Standard Population and World Health Organization), to compare our results with other studies.

RESULTS

The overall crude incidence of stroke in Brno was 213/100,000 population. The incidence of stroke for stroke types were as follows: SAH, 6.9; ICH, 26.4; and IS, 180 cases per 100,000 population, respectively. The WHO-standardized annual stroke incidence was 107 for all strokes and 88 for IS, 14.4 for ICH, and 5 for SAH. For IS subtypes, the WHO-standardized incidence was large artery atherosclerosis 25.8, cardioembolism 27.8, lacunar 21.6, other determined etiology 6.2, and undetermined etiology 6.5 cases per 100,000 population.

CONCLUSIONS

The stroke incidence is lower than that previously reported for the CR and Eastern Europe probably reflecting socioeconomic changes in post-communistic countries in the region. These findings could contribute to stroke prevention strategies and influence health policies.

Validity of Acute Cardiovascular Outcome Diagnoses Recorded in European Electronic Health Records: A Systematic Review

BACKGROUND

Electronic health records are widely used in cardiovascular disease research. We appraised the validity of stroke, acute coronary syndrome and heart failure diagnoses in studies conducted using European electronic health records.

METHODS

Using a prespecified strategy, we systematically searched seven databases from dates of inception to April 2019. Two reviewers independently completed study selection, followed by partial parallel data extraction and risk of bias assessment. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value estimates were narratively synthesized and heterogeneity between sensitivity and PPV estimates were assessed using I2.

RESULTS

We identified 81 studies, of which 20 validated heart failure diagnoses, 31 validated acute coronary syndrome diagnoses with 29 specifically recording estimates for myocardial infarction, and 41 validated stroke diagnoses. Few studies reported specificity or negative predictive value estimates. Sensitivity was ≤66% in all but one heart failure study, ≥80% for 91% of myocardial infarction studies, and ≥70% for 73% of stroke studies. PPV was ≥80% in 74% of heart failure, 88% of myocardial infarction, and 70% of stroke studies. PPV by stroke subtype was variable, at ≥80% for 80% of ischaemic stroke but only 44% of haemorrhagic stroke. There was considerable heterogeneity (I2 >75%) between sensitivity and PPV estimates for all diagnoses.

CONCLUSION

Overall, European electronic health record stroke, acute coronary syndrome and heart failure diagnoses are accurate for use in research, although validity estimates for heart failure and individual stroke subtypes were lower. Where possible, researchers should validate data before use or carefully interpret the results of previous validation studies for their own study purposes.

The role of mental disease on the association between multimorbidity and medical expenditure

BACKGROUND

Multimorbidity is the presence of two or more chronic diseases and is associated with increased adverse outcomes, including hospitalization, mortality and frequency of use of medical institutions.

OBJECTIVE

This study aimed to describe multimorbidity patterns, determine whether multimorbidity was associated with high medical expenditure, and determine whether mental diseases had an interaction effect on this association.

METHODS

We conducted a claims data-based observational study. Data were obtained for 7526 individuals aged 0-75 years from a medical claims data set for Goto, Japan, over a 12-month period (2016-17). Annual medical expenditure was divided into quintiles; the fifth quintile represented high medical expenditure. Multimorbidity status was defined as the occurrence of two or more health conditions from 17 specified conditions. Odds ratios (OR) and 95% confidence intervals (CI) for high medical expenditure were calculated by number of comorbidities.

RESULTS

In total, 5423 (72.1%) participants had multimorbidity. Multimorbidity was significantly associated with high medical expenditure, even after adjustment for age, sex and income category (OR: 10.36, 95% CI: 7.57-14.19; P < 0.001). Mental diseases had a significant interaction effect on the association between multimorbidity and high medical expenditure (P = 0.001).

CONCLUSIONS

Multimorbidity is associated with high medical expenditure in Japan. Mental diseases may contribute to increased medical costs.

Long-term prognosis after intracerebral haemorrhage

Introduction

The aim of this study was to determine the risk of recurrent intracerebral haemorrhage (ICH), ischaemic stroke, all stroke, any vascular event and all-cause mortality in 30-day survivors of ICH, according to age and sex.

Patients and methods

We linked national hospital discharge, population and cause of death registers to obtain a cohort of Dutch 30-day survivors of ICH from 1998 to 2010. We calculated cumulative incidences of recurrent ICH, ischaemic stroke, all stroke and composite vascular outcome, adjusted for competing risk of death and all-cause mortality. Additionally, we compared survival with the general population.

Results

We included 19,444 ICH-survivors (52% male; median age 72 years, interquartile range 61–79; 78,654 patient-years of follow-up). First-year cumulative incidence of recurrent ICH ranged from 1.5% (95% confidence interval 0.9–2.3; men 35–54 years) to 2.4% (2.0–2.9; women 75–94 years). Depending on age and sex, 10-year risk of recurrent ICH ranged from 3.7% (2.6–5.1; men 35–54 years) to 8.1% (6.9–9.4; women 55–74 years); ischaemic stroke 2.6% to 7.0%, of all stroke 9.9% to 26.2% and of any vascular event 15.0% to 40.4%. Ten-year mortality ranged from 16.7% (35–54 years) to 90.0% (75–94 years). Relative survival was lower in all age-groups of both sexes, ranging from 0.83 (0.80–0.87) in 35- to 54-year-old men to 0.28 (0.24–0.32) in 75- to 94-year-old women.

Discussion

ICH-survivors are at high risk of recurrent ICH, of ischaemic stroke and other vascular events, and have a sustained reduced survival rate compared to the general population.

Conclusion

The high risk of recurrent ICH, other vascular events and prolonged reduced survival-rates warrant clinical trials to determine optimal secondary prevention treatment after ICH.

Incidence of Hospitalization for Stroke in Queensland, Australia: Younger Adults at Risk

BACKGROUND

Trends in the incidence of stroke are important for health care planning. Information is particularly scarce in Australia, due to the paucity of studies with access to recent, large-scale, longitudinal datasets. In this paper we investigated the incidence of hospitalization for stroke by sex, age, and subtype in the whole State of Queensland (Australia).

METHODS

We obtained data of all hospital admissions for stroke in Queensland from 2002 to 2015. Age standardized hospitalization rates for first-ever stroke were calculated along with WHO adjusted rates. Poisson regression analyses were conducted to investigate the influence of time and gender on the incidence of subtypes of stroke as well as the total incidence.

RESULTS

Admissions for first-ever stroke were 57,597. Crude hospitalization incidence rose from 87 (95% confidence interval [CI], 84-90) to 108 (95%CI, 105-111) for both sexes. The highest increase was in the age bands 40-49 from 33 (95%CI, 26-40) to 54 (95%CI, 46-62; +62%) and 50-59 from 82 (95%CI, 70-93) to 127 (95%CI, 114-140; +56%) in men and in 60-69 from 118 (95%CI, 100-136) to 159 (95%CI, 143-175; +34%) in women. Ischemic subtype rates appeared to increase more than haemorrhagic rates. Age range, sex, and year reliably predicted incidence rates.

CONCLUSIONS

If these trends are maintained, the data predict further increases, especially in males aged 40-59. With people apparently stroking earlier and mortality rates dropping, the healthcare system in Australia is faced with a rapidly increasing care burden.

Trends in One Month and One Year Hemorrhagic Stroke Case Fatality Rates in the Czech Republic between 1998 and 2015

BACKGROUND

This retrospective cross-sectional study reports 1 month and 1 year intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) case fatality rates and their temporal trends in the Czech Republic between 1998 and 2015.

METHODS

Utilizing the National Register of Hospitalized Patients, we randomly selected 600 patients hospitalized for ICH and 600 patients hospitalized for SAH for each year from 1998 to 2015, and identified those who died, regardless of cause, using the Czech National Mortality Registry. We calculated crude and age-adjusted 1 month and 1 year case fatality rates for ICH and SAH. Long-term trends of the crude rates were analyzed using a one-sided Cochran Armitage test.

RESULTS

A total of 21,600 cases hospitalized for SAH and ICH (10,800 for each) between 1998 and 2015 were randomly selected for analysis. One month case fatality of SAH overall and in women has decreased by 0.2% (P = .006) and 0.3% per year (P = .04), respectively. Overall 1 year case fatality of SAH has decreased by 0.2% per year (P = .03). One month case fatality rate of ICH overall and in men has decreased by 0.2% (p=0.01) and 0.4% (P = .0007), respectively. One year case fatality of ICH in men has decreased by 0.2% per year (P = .047).

CONCLUSIONS

One month and 1 year case fatality rates for SAH and ICH have been decreasing in the Czech Republic between 1998 and 2015, and are similar or lower than those reported from other developed European countries.

Risk Factors in Ischemic Stroke Subtypes: A Community-Based Study in Brno, Czech Republic

BACKGROUND

It is not known if risk factors differ between ischemic stroke (IS) subtypes in Central and Eastern Europe.

AIMS

We performed a community-based analysis of risk factors in patients admitted with IS over a 1 year period in Brno, the second largest city in the Czech Republic (CR).

METHODS

Based on the National Register of Hospitalized Patients, all patients with IS admitted in Brno in 2011 were identified. Comprehensive discharge summaries from hospital admissions were collected and reviewed. IS subtype and relevant risk factors were ascertained for all patients. The age- and sex-adjusted association of risk factors with IS subtypes was determined.

RESULTS

Overall, 682 patients with IS were admitted in 2011 to Brno hospitals. The distribution of IS subtypes was: 35% cardioembolism, 28% large-artery atherosclerosis, 23% small-artery occlusion, 7% stroke of undetermined etiology, 7% stroke of other determined etiology. Several of the risk factors showed high prevalence in the overall sample - e.g. hypertension (84%) and hyperlipidemia (61%). Cardioembolism as compared to other subtypes was positively associated with a history of myocardial infarction, cardiac failure, and atrial fibrillation. Small-artery occlusion was positively associated with history of dementia. No significant association was found between IS subtypes and history of IS, hypertension, diabetes, obesity, alcohol abuse or smoking.

CONCLUSIONS

We found high frequency of stroke risk factors in all IS subtypes. These findings have implications for stroke prevention strategies in the CR and across Central Europe.

Accuracy of surgical complication rate estimation using ICD-10 codes

Background

The ICD‐10 codes are used globally for comparison of diagnoses and complications, and are an important tool for the development of patient safety, healthcare policies and the health economy. The aim of this study was to investigate the accuracy of verified complication rates in surgical admissions identified by ICD‐10 codes and to validate these estimates against complications identified using the established Global Trigger Tool (GTT) methodology.

Methods

This was a prospective observational study of a sample of surgical admissions in two Norwegian hospitals. Complications were identified and classified by two expert GTT teams who reviewed patients' medical records. Three trained reviewers verified ICD‐10 codes indicating a complication present on admission or emerging in hospital.

Results

A total of 700 admissions were drawn randomly from 12 966 procedures. Some 519 possible complications were identified in 332 of 700 admissions (47·4 per cent) from ICD‐10 codes. Verification of the ICD‐10 codes against information from patients' medical records confirmed 298 as in‐hospital complications in 141 of 700 admissions (20·1 per cent). Using GTT methodology, 331 complications were found in 212 of 700 admissions (30·3 per cent). Agreement between the two methods reached 83·3 per cent after verification of ICD‐10 codes. The odds ratio for identifying complications using the GTT increased from 5·85 (95 per cent c.i. 4·06 to 8·44) to 25·38 (15·41 to 41·79) when ICD‐10 complication codes were verified against patients' medical records.

Conclusion

Verified ICD‐10 codes strengthen the accuracy of complication rates. Use of non‐verified complication codes from administrative systems significantly overestimates in‐hospital surgical complication rates.

Code correctly

Validation of intracranial hemorrhage in the Norwegian Patient Registry

Objectives

Administrative health registries need to have accurate diagnoses and sufficient coverage in the population they serve in order to be useful in research. In this study, we investigated the proportion of discharge diagnoses of intracranial hemorrhage (ICH) that were coded correctly in the Norwegian Patient Registry (NPR).

Materials and Methods

We reviewed the electronic medical records and diagnostic imaging of all admissions to St. Olavs University Hospital, Trondheim, Norway, between January 1, 2008, to December 31, 2014, with a discharge diagnosis of ICH in the NPR, and estimated positive predictive values (PPVs) for primary and secondary diagnoses. Separate calculations were made for inpatient and outpatient admissions.

Results

In total, 1,419 patients with 1,458 discharge diagnoses of ICH were included in our study. Overall, 1,333 (91.4%) discharge diagnoses were coded correctly. For inpatient admissions, the PPVs for primary discharge codes were 96.9% for hemorrhagic stroke, 95.3% for subarachnoid hemorrhage, and 97.9% for subdural hemorrhage. The most common cause of incorrect diagnosis was previous stroke that should have been coded as rehabilitation or sequela after stroke. There were more false-positive diagnoses among outpatient consultations and secondary diagnoses.

Conclusion

Coding of ICH discharge diagnoses in the NPR is of high quality, showing that data from this registry can safely be used for medical research.

Decreasing Risk of Fatal Subarachnoid Hemorrhage and Other Epidemiological Trends in the Era of Coiling Implementation in Australia

BACKGROUND AND PURPOSE

Subarachnoid hemorrhage (SAH) is associated with a high risk of mortality and disability in survivors. We examined the epidemiology and burden of SAH in our population during a time services were re-organized to facilitate access to evidence-based endovascular coiling and neurosurgical care.

METHODS

SAH hospitalizations from 2001 to 2009, in New South Wales, Australia, were linked to death registrations to June 30, 2010. We assessed the variability of admission rates, fatal SAH rates and case fatality over time and according to patient demographic characteristics.

RESULTS

There were 4,945 eligible patients admitted to hospital with SAH. The risk of fatal SAH significantly decreased by 2.7% on average per year (95% CI = 0.3-4.9%). Case fatality at 2, 30, 90, and 365 days significantly declined over time. The average annual percentage reduction in mortality ranged from 4.4% for 30-day mortality (95% CI -6.1 to -2.7) (P < 0.001) to 4.7% for mortality within 2 days (-7.1 to -2.2) (P < 0.001) (Table 3). Three percent of patients received coiling at the start of the study period, increasing to 28% at the end (P-value for trend <0.001). Females were significantly more likely to be hospitalized for a SAH compared to males [incident rate ratio (IRR) = 1.33, 95% CI = 1.23-1.44] (P < 0.001) and to die from SAH (IRR = 1.40, 95% CI = 1.24-1.59) (P < 0.001). People born in South-East Asia and the Oceania region had a significantly increased risk of SAH, while the risk of fatal SAH was greater in South-East and North-East Asian born residents. People residing in areas of least disadvantage had the lowest risk of hospitalization (IRR = 0.83, 95% CI = 0.74-0.92) and also the lowest risk of fatal SAH (0.81, 95% CI = 0.66-1.00) (P < 0.001 and P = 0.003, respectively). For every 100 SAH admissions, 20 and 15 might be avoided in males and females, respectively, if the risk of SAH in our population equated to that of the most socio-economically advantaged.

CONCLUSION

Our study reports reductions in mortality risk in SAH corresponding to identifiable changes in health service delivery and evolving treatments such as coiling. Addressing inequities in SAH risk and mortality may require the targeting of prevalent and modifiable risk factors to improve population outcomes.

Incidence of Hospitalized Stroke in the Czech Republic: The National Registry of Hospitalized Patients

BACKGROUND

Contemporary stroke incidence data are not available in some countries and regions, including in Eastern Europe. Based on previous validation of the accuracy of the National Registry of Hospitalized Patients (NRHOSP), we report the incidence of hospitalized stroke in the Czech Republic (CR) using the NRHOSP.

METHODS

The results of the prior validation study assessing the accuracy of coding of stroke diagnoses in the NRHOSP were applied, and we calculated (1) the overall incidence of hospitalized stroke and (2) the incidence rates of hospitalized stroke for the three main stroke types: cerebral infarction (International Classification of Diseases Tenth Revision, CI I63), subarachnoid hemorrhage (SAH I60), and intracerebral hemorrhage (ICH I61). We calculated the average annual age- and sex-standardized incidence.

RESULTS

The overall incidence of hospitalized stroke was 241 out of 100,000 individuals. The incidence of hospitalized stroke for the main stroke types was 8.2 cases in SAH, 29.5 in ICH, and 211 in CI per 100,000 individuals. The standardized annual stroke incidence adjusted to the 2000 World Health Organization population for overall stroke incidence of hospitalized stroke was 131 per 100,000 individuals. Standardized stroke incidence for stroke subtypes was 5.7 cases in SAH, 16.7 in ICH, and 113 in CI per 100,000 individuals.

CONCLUSIONS

These studies provide an initial assessment of the burden of stroke in this part of the world. The estimates of hospitalized stroke in the CR and Eastern Europe suggest that ICH is about three times more common than SAH, and hemorrhagic stroke makes up about 18% of strokes.

Population-Based Incidence Rates of First-Ever Stroke in Central Vietnam

Introduction

Stroke incidence data with methodologically acceptable design in Southeast Asia countries is limited. This study aimed to determine incidence of age-, sex- and subtype-specific first-ever stroke (FES) in Vietnam.

Methods

We conducted a hospital-based retrospective study, targeting all stroke cases hospitalized at a solo-provider hospital in our study site of Nha Trang from January 2009 to December 2011 with International Classification of Diseases, 10th revision (ICD-10) codes I60-69. We calculated positive predictive values (PPVs) of each ICD-10-coded stroke by conducting a detailed case review of 190 randomly selected admissions with ICD-10 codes of I60-I69. These PPVs were then used to estimate annual incident stroke cases from the computerized database. National census data in 2009 was used as a denominator.

Results

2,693 eligible admissions were recorded during the study period. The crude annual incidence rate of total FES was 90.2 per 100,000 population (95% CI 81.1–100.2). The age-adjusted incidence of FES was 115.7 (95% CI 95.9–139.1) when adjusted to the WHO world populations. Importantly, age-adjusted intracerebral hemorrhage was as much as one third of total FES: 36.9 (95% CI 26.1–51.0).

Conclusions

We found a considerable proportion of FES in Vietnam to be attributable to intracerebral hemorrhage, which is as high or exceeding levels seen in high-income countries. A high prevalence of improperly treated hypertension in Vietnam may underlie the high prevalence of intracerebral hemorrhagic stroke in this population.

The High Frequency of Guideline-Approved and Guideline-Disapproved Medication Use in Stroke and Transient Ischemic Attack

BACKGROUND AND PURPOSE

Administration of evidence-based pharmacotherapy improves stroke outcome while the use of non-evidence-based medications may not be of benefit and leads to unnecessary patient care costs. The aim of our study was to determine the frequency of guideline-approved and guideline-disapproved pharmacotherapy use in acute stroke management in the Czech Republic (CR).

METHODS

Using the ICD-10 codes, 500 stroke and transient ischemic attack (TIA) patients were randomly selected (random selection of 10 hospitals and then 50 patients from each hospital) from the National Registry of Hospitalized Patients for strokes occurring in 2011. Discharge summaries were reviewed for medications prescribed during hospitalization and at discharge.

RESULTS

Of the 500 requested discharge summaries, 484 were available for review (response rate 97%). Up to 479 (96%) summaries were sufficient for evaluation and of these, 393 were confirmed to have a stroke or TIA diagnosis. Brain imaging (computed tomography or magnetic resonance imaging) was performed in 97% of the 393 cases. Intravenous thrombolysis was administered to 7% of patients with ischemic stroke (rate was 0%-25% in different hospitals). Up to 97% of patients with ischemic events (TIA or ischemic stroke) were treated with antiplatelets or anticoagulants. At least 1 non-evidence-based medication was administered to 28% of the 393 patients (rate was 5%-89% in different hospitals).

CONCLUSIONS

Guideline-disapproved pharmacotherapy is common in stroke and TIA patients in the CR and processes should be put into place to lessen the frequency of their use. The use of guideline-approved medications is also high and should be further promoted.