Temporal trends in stroke admissions in Denmark 1997-2009

Epidemiology, clinical features and outcome of stroke in rural versus urban hospitals in Cameroon

OBJECTIVES

Stroke is a major public health problem worldwide with disparities between urban and rural areas. The aim of this study was to compare the epidemiological, clinical features and outcomes of stroke between rural and urban hospitals in Cameroon.

MATERIALS AND METHODS

We conducted a retrospective cohort study at the Douala General Hospital (urban) and Ad Lucem Hospital of Banka (rural) from January 1st, 2014, to December 31st, 2019. The medical records of all patients admitted for stroke, and meeting the inclusion criteria were reviewed. Diagnosis of stroke was based on brain imaging and/or the World Health Organization definition. Data were analyzed using SPSS version 20.0.

RESULTS

Among the 15277 files reviewed, 752 were included with 623 cases (82.80%) in urban areas. The percentage of patients hospitalized for stroke were 9.06% and 2.85% in urban and rural hospitals respectively. The frequency of patients admitted for severe stroke (Glasgow coma scale ≤ 8) was higher in the rural hospital (p = 0.004). In-hospital mortality (p = 0.010), cumulative mortality at one-month (p = 0.018), poor functional recovery (p = 0.002), one-year stroke recurrence (p = 0.020) were significantly higher in rural setting. Undefined stroke was predictor of mortality in the rural hospital, while hemorrhagic stroke was predictor of mortality at one-month in the urban hospital.

CONCLUSIONS

Stroke cases were significantly more severe with poor outcomes in the rural hospital. Efforts are needed to improve prevention, and access to stroke care for communities, especially in rural setting.

Diverging Temporal Trends in Stroke Incidence in Younger vs Older People: A Systematic Review and Meta-analysis

Importance

Overall stroke incidence is falling in high-income countries, but data on time trends in incidence of young stroke (ie, stroke in individuals younger than 55 years) are conflicting. An age-specific divergence in incidence, with less favorable trends at younger vs older ages, might be a more consistent underlying finding across studies.

Objective

To compare temporal trends in incidence of stroke at younger vs older ages in high-income countries.

Data Sources

PubMed and EMBASE were searched from inception to February 2022. One additional population-based study (Oxford Vascular Study) was also included.

Study Selection

Studies reporting age-specific stroke incidence in high-income countries at more than 1 time point.

Data Extraction and Synthesis

For all retrieved studies, 2 authors independently reviewed the full text against the inclusion criteria to establish their eligibility. Meta-analysis was performed with the inverse variance-weighted random-effects model. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed.

Main Outcomes and Measures

The main outcome was age-specific divergence (<55 vs ≥55 years) in temporal trends in stroke incidence (relative temporal rate ratio [RTTR]) in studies extending to at least 2000. RTTRs were calculated for each study and pooled by random-effects meta-analysis, with stratification by administrative vs prospective population-based methodology, sex, stroke subtype (ischemic vs intracerebral hemorrhage vs subarachnoid hemorrhage) and geographical region.

Results

Among 50 studies in 20 countries, 26 (13 prospective population-based and 13 administrative studies) reported data allowing calculation of the RTTR for stroke incidence at younger vs older ages across 2 or more periods, the latest extending beyond 2000. Reported trends in absolute incidence of young individuals with stroke were heterogeneous, but all studies showed a less favorable trend in incidence at younger vs older ages (pooled RTTR = 1.57 [95% CI, 1.42-1.74]). The overall RTTR was consistent by stroke subtype (ischemic, 1.62 [95% CI, 1.44-1.83]; intracerebral hemorrhage, 1.32 [95% CI, 0.91-1.92]; subarachnoid hemorrhage, 1.54 [95% CI, 1.00-2.35]); and by sex (men, 1.46 [95% CI, 1.34-1.60]; women, 1.41 [95% CI, 1.28-1.55]) but was greater in studies reporting trends solely after 2000 (1.51 [95% CI, 1.30-1.70]) vs solely before (1.18 [95% CI, 1.12-1.24]) and was highest in population-based studies in which the most recent reported period of ascertainment started after 2010 (1.87 [95% CI, 1.55-2.27]).

Conclusions and Relevance

Temporal trends in stroke incidence are diverging by age in high-income countries, with less favorable trends at younger vs older ages, highlighting the urgent need to better understand etiology and prevention of stroke at younger ages.

Frequency of Neurological Diseases After COVID-19, Influenza A/B and Bacterial Pneumonia

Introduction

COVID-19 might affect the incidence of specific neurological diseases, but it is unknown if this differs from the risk following other infections. Here, we characterized the frequency of neurodegenerative, cerebrovascular, and immune-mediated neurological diseases after COVID-19 compared to individuals without COVID-19 and those with other respiratory tract infections.

Methods

This population-based cohort study utilized electronic health records covering ~50% of Denmark's population (n = 2,972,192). Between 02/2020 and 11/2021, we included individuals tested for COVID-19 or diagnosed with community-acquired bacterial pneumonia in hospital-based facilities. Additionally, we included individuals tested for influenza in the corresponding pre-pandemic period between 02/ 2018 and 11/2019. We stratified cohorts for in- and outpatient status, age, sex, and comorbidities.

Results

In total, 919,731 individuals were tested for COVID-19, of whom 43,375 tested positive (35,362 outpatients, 8,013 inpatients). Compared to COVID-negative outpatients, COVID-19 positive outpatients had an increased RR of Alzheimer's disease (RR = 3.5; 95%CI: 2.2–5.5) and Parkinson's disease (RR = 2.6; 95%CI: 1.7–4.0), ischemic stroke (RR = 2.7; 95%CI: 2.3–3.2) and intracerebral hemorrhage (RR = 4.8; 95%CI: 1.8–12.9). However, when comparing to other respiratory tract infections, only the RR for ischemic stroke was increased among inpatients with COVID-19 when comparing to inpatients with influenza (RR = 1.7; 95%CI: 1.2–2.4) and only for those &gt;80 years of age when comparing to inpatients with bacterial pneumonia (RR = 2.7; 95%CI: 1.2–6.2). Frequencies of multiple sclerosis, myasthenia gravis, Guillain-Barré syndrome and narcolepsy did not differ after COVID-19, influenza and bacterial pneumonia.

Conclusion

The risk of neurodegenerative and cerebrovascular, but not neuroimmune, disorders was increased among COVID-19 positive outpatients compared to COVID-negative outpatients. However, except for ischemic stroke, most neurological disorders were not more frequent after COVID-19 than after other respiratory infections.

Gender differences in time to first hospital admission at age 60 in Denmark, 1995-2014

Women have consistently lower mortality rates than men at all ages and with respect to most causes. However, gender differences regarding hospital admission rates are more mixed, varying across ages and causes. A number of intuitive metrics have previously been used to explore changes in hospital admissions over time, but have not explicitly quantified the gender gap or estimated the cumulative contribution from cause-specific admission rates. Using register data for the total Danish population between 1995 and 2014, we estimated the time to first hospital admission for Danish men and women aged 60. This is an intuitive population-level metric with the same interpretive and mathematical properties as period life expectancy. Using a decomposition approach, we were able to quantify the cumulative contributions from eight causes of hospital admission to the gender gap in time to first hospital admission. Between 1995 and 2014, time to first admission increased for both, men (7.6 to 9.4 years) and women (8.3 to 10.3 years). However, the magnitude of gender differences in time to first admission remained relatively stable within this time period (0.7 years in 1995, 0.9 years in 2014). After age 60, Danish men had consistently higher rates of admission for cardiovascular conditions and neoplasms, but lower rates of admission for injuries, musculoskeletal disorders, and sex-specific causes. Although admission rates for both genders have generally declined over the last decades, the same major causes of admission accounted for the gender gap. Persistent gender differences in causes of admission are, therefore, important to consider when planning the delivery of health care in times of population ageing.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10433-021-00614-w.

Time trends in the risk of atrial fibrillation and ischaemic stroke in patients with peripheral artery disease between 1997 and 2015

Objective

The risk of atrial fibrillation (AF) and stroke in patients with peripheral artery disease (PAD) is an important issue that has not been investigated adequately. Our aim with the present study was to explore trends in the incidence of AF and stroke in patients with PAD.

Methods

We employed Danish nationwide registers to identify all patients with first-time diagnosis of PAD (aged ≥18 years) between 1997 and 2015. Age-standardised incidence rates per 1 000 person-years were calculated to estimate trends of AF and stroke. Risk of AF and stroke was estimated by 1 year cumulative incidence.

Results

A total of 121.241 patients with first-time diagnosis of PAD were identified. The 1-year cumulative incidence of AF in patients with PAD were 1.97% for year 1997–2000, 2.63% for year 2001–2005, 2.66% for year 2006–2010 and 2.78% for year 2011–2015, respectively. The 1-year cumulative incidence of stroke in patients with PAD were 2.71%, 2.71%, 1.95% and 1.81%, for the 1997–2000, 2001–2005, 2006–2010 and 2011–2015 year groups, respectively. Likewise, the age-standardised incidence rates showed increasing trends of AF during the study period, whereas trends of stroke demonstrated a decline. During study, the initiation of cholesterol-lowering agents and clopidogrel increased markedly from 7.0% to 51.3% and 0.1% to 5.9%, whereas use of warfarin slightly dropped from 4.29% to 3.21%.

Conclusions

The incidence of AF in patients with PAD has significantly increased over time, whereas a marked decline has occurred in the incidence of stroke. This may suggest that the secondary prevention strategies aimed at reducing risk of stroke are broadly effective.

Time trends in incidence, comorbidity, and mortality of ischemic stroke in Denmark (1996–2016)

Objective

To examine whether the incidence, comorbidity, and mortality of first-time ischemic stroke changed in Denmark between 1996 and 2016 overall and according to age and sex using a nationwide cohort design.

Methods

In this cohort study, 224,617 individuals ≥18 years of age admitted with first-time ischemic stroke between 1996 and 2016 were identified through Danish nationwide registries. We calculated annual age-standardized incidence rates and absolute 30-day and 1-year mortality risks. Furthermore, we calculated annual incidence rate ratios using Poisson regression, odds ratios for 30-day mortality using logistic regression, and hazard ratios for 1-year mortality using Cox regression.

Results

The overall age-standardized incidence rates of ischemic stroke per 1,000 person-years increased from 1996 (2.70 [95% confidence interval [CI] 2.65–2.76]) to 2002 (3.25 [95% CI 3.20–3.31]) and then gradually decreased to below the initial level until 2016 (1.99 [95% CI 1.95–2.02]). Men had higher incidence rates than women in all age groups except 18 to 34 and ≥85 years. Absolute mortality risk decreased between 1996 and 2016 (30-day mortality from 17.1% to 7.6% and 1-year mortality from 30.9% to 17.3%). Women between 55 and 64 and ≥85 years of age had higher mortality than men. Similar trends were observed for all analyses after multivariable adjustment. The prevalence of atrial fibrillation, hypertension, diabetes mellitus, and use of lipid-lowering medication increased during the study period.

Conclusions

The age-standardized incidence of first-time hospitalization for ischemic stroke increased from 1996 to 2002 and then gradually decreased to below the initial level until 2016. Absolute 30-day and 1-year mortality risks decreased between 1996 and 2016. These findings correspond to increased stroke prevention awareness and introduction of new treatments during the study period.

Age-specific trends in incidence and survival of out-of-hospital cardiac arrest from presumed cardiac cause in Denmark 2002-2014

BACKGROUND

The general cardiovascular health has improved throughout the last few decades for middle-aged and older individuals, but the incidence of several cardiovascular diseases is reported to increase in younger people. We aimed to assess the age-specific incidence and mortality rates associated with out-of-hospital-cardiac-arrest (OHCA) between 2002 and 2014.

METHODS

We used the Danish Cardiac Arrest Register to identify patients with OHCA of presumed cardiac etiology. We calculated the annual incidence rates (IR) and 30-day mortality rates (MR) in 7 age groups (18-34 years, 35-44 years, 45-54 years, 55-64 years, 65-74 years, 75-84 years and ≥85 years, and ≤50 vs. >50 years).

RESULTS

Between 2002 and 2014, IR of OHCA decreased in individuals aged 65-74 and 75-84 years (158.08 to 111.2 and 237.5 to 217.09 per 100,000 person-years) and increased in the oldest from 201.01 to 325.4 pr. 100.000 person-years. In 18-34-years incidence of OHCA increased from 1.7 to 2.6 per 100.000 person-years. When stratifying into age ≤50 vs. >50 years, the IR deviated in those >50 years (from 117.8 in 2002 to 91 in 2008 to 117.4 in 2014100,000 person-years). The prevalence of acute myocardial infarction and heart failure prior to OHCA increased in the younger patient group in contrast to the older segment (AMI: ≤50 years: 10% to 16%, vs. >50 years: 25% to 23%, heart failure: ≤50 years 6% to 14%, vs. >50 years: 21% to 24%).

CONCLUSION

Over the last decades, incidence rates of OHCA decreased in individuals aged 65-84, but increased in individuals older than 85. An increase was also observed in younger individuals, potentially indicating a need for better cardiovascular disease prevention in younger adults.

Incidence and Risk Factors for Stroke in Fast-Track Hip and Knee Arthroplasty-A Clinical Registry Study of 24,862 Procedures

BACKGROUND

Postoperative stroke is a severe complication with a reported 30-day incidence of 0.4%-0.6% after total hip (THA) and knee arthroplasty (TKA). However, most data are based on diagnostic codes and with limited details on perioperative care, including the use of fast-track protocols. We investigated the incidence of and preoperative and postoperative factors for stroke after fast-track THA/TKA.

METHODS

We used an observational study design of elective fast-track THA/TKA patients with prospective collection of comorbidity and complete 90-day follow-up. Medical records were evaluated for events potentially disposing to stroke. Identification of relevant preoperative risk factors was done by multivariable logistic regression. Incidence of stroke was compared with a Danish background population.

RESULTS

Of 24,862 procedures with a median length of stay of 2 (interquartile range, 2-3) days, we found 27 (0.11%; 95% confidence interval [CI], 0.08%-0.16%) and 43 strokes (0.17%, 95% CI, 0.13%-0.23%) ≤30 and ≤90 days after surgery, respectively. Preoperative risk factors for stroke ≤30 days were age ≥ 85 years (odds ratio [OR], 4.3; 95% CI, 1.1-16.3) and anticoagulant treatment (OR, 3.1; 95% CI, 1.2-7.9). Preoperative anemia was near significant (OR, 2.1; 95% CI, 0.98-4.6, P = .055). Eight strokes ≤30 days were preceded by a cardiovascular event within the second postoperative day. Incidence of stroke after postoperative day 30 was similar to a Danish background population.

CONCLUSION

Risk of postoperative stroke in fast-track THA and TKA was low but may be further reduced with increased focus on avoiding perioperative cardiovascular events and in patients with preoperative anticoagulants or anemia.

Declining Rate and Severity of Hospitalized Stroke From 2004 to 2013: The National Acute Stroke Israeli Registry

BACKGROUND AND PURPOSE

Stroke is a leading cause of morbidity and disability. We assessed trends in rates of hospitalized stroke and stroke severity on admission in a prospective national registry of stroke from 2004 to 2013.

METHODS

All 6693 acute ischemic strokes and intracerebral hemorrhage in the National Acute Stroke Israeli participants ≥20 years old were included. Data were prospectively collected in 2004 (February-March), 2007 (March-April), 2010 (April-May), and 2013 (March-April). Rates of hospitalized stroke from 2004 to 2013 were studied using generalized linear models assuming a quasi-Poisson error distribution with a log link. Stroke severity on admission was determined using the National Institutes of Health Stroke Scale score and trends were studied. Analysis was performed for stroke overall and by sex and age-group as well as by stroke type.

RESULTS

Estimated average annual rates of hospitalized stroke decreased from 24.9/10 000 in 2004 to 19.5/10 000 in 2013. The age and sex-adjusted rates ratio (95% confidence interval) for hospitalized stroke overall was 0.82 (0.76-0.89) for 2007, 0.71 (0.65-0.77) for 2010, and 0.72 (0.66-0.78) for 2013 compared with 2004. Severity on admission decreased over time: rates (95% confidence interval) of severe stroke (National Institutes of Health Stroke Scale score of ≥11) decreased from 27% (25%-29%) in 2004 to 19% (17%-21%) in 2013, whereas rates (95% confidence interval) of minor stroke (National Institutes of Health Stroke Scale score of ≤5) increased from 46% (44%-49%) in 2004 to 60% (57%-62%) in 2013 (P<0.0001). Findings were consistent by sex, age-group, and stroke type.

CONCLUSIONS

Based on our national data, rates of hospitalized stroke and severity of stroke on admission have decreased from 2004 to 2013 overall and by stroke type, in men and women. Despite the observed declines in rates and severity, stroke continues to place a considerable burden to the Israeli health system.

Comorbidity and the increased mortality after hospitalization for stroke: a population-based cohort study

Essentials Comorbidity is prevalent in the stroke population and affects post-stroke survival. A stroke patient cohort (n = 201 691) and a general population cohort were followed for survival. Cancer and advanced renal/liver disease substantially increased one-year stroke mortality. Tailoring stroke interventions according to comorbidity may reduce excess mortality.

SUMMARY

Background Comorbidity is prevalent among stroke patients, affecting post-stroke survival. It remains unknown whether comorbidity impacts post-stroke mortality beyond the combined individual effects of stroke and comorbidity. Methods Using nationwide Danish databases, we performed a cohort study of 201 691 patients ≥ 18 years old with incident ischemic stroke, intracerebral or subarachnoid hemorrhage, or unspecified stroke during 1995-2012, and 992 942 adults from the general population, matched to stroke patients by birth year, sex and individual comorbidities in the Charlson Comorbidity Index. During up to 5 years of follow-up, we computed standardized mortality rates (SMRs) to assess interaction contrasts as a measure of excess mortality not explained by the additive effects of stroke and comorbidity acting alone. Results Five-year post-stroke mortality was 48%, corresponding to an SMR of 187 deaths per 1000 person-years. During the 30-day peak post-stroke mortality (SMR, 180 per 1000 person-months), interaction with comorbidity represented 23%, 34% and 51% of post-stroke mortality rates among patients with low (score = 1), moderate (score = 2-3) and high (score = 4+) comorbidity based on Charlson Comorbidity Index scores. The interaction accounted for 5% to 32% of subsequent 31-365-day post-stroke mortality rates, depending on comorbidity level. The interaction contrasts were most notable among comorbid patients with cancer, particularly with hematological or metastatic disease, followed by patients with moderate-to-severe liver or renal disease. Conclusion Comorbidity, notably cancer and advanced renal or liver disease, increased 1-year mortality after stroke beyond the combined effects expected from either disease acting alone.

Association of Childhood Body Mass Index and Change in Body Mass Index With First Adult Ischemic Stroke

Importance

The incidence of ischemic stroke among young adults is rising and is potentially due to an increase in stroke risk factors occurring at younger ages, such as obesity.

Objectives

To investigate whether childhood body mass index (BMI) and change in BMI are associated with adult ischemic stroke and to assess whether the associations are age dependent or influenced by birth weight.

Design, Setting, and Participants

This investigation was a population-based cohort study of schoolchildren born from 1930 to 1987, with follow-up through national health registers from 1977 to 2012 in Denmark. Participants were 307 677 individuals (8899 ischemic stroke cases) with measured weight and height at ages 7 to 13 years. The dates of the analysis were September 1, 2015, to May 27, 2016.

Main Outcomes and Measures

Childhood BMI, change in BMI, and birth weight. Ischemic stroke events were divided into early (≤55 years) or late (>55 years) age at diagnosis.

Results

The study cohort comprised 307 677 participants (approximately 49% female and 51% male). During the study period, 3529 women and 5370 men experienced an ischemic stroke. At all ages from 7 to 13 years, an above-average BMI z score was positively associated with early ischemic stroke. At age 13 years, a BMI z score of 1 was associated with hazard ratios (HRs) of 1.26 (95% CI, 1.11-1.43) in women and 1.21 (95% CI, 1.10-1.33) in men. No significant associations were found for below-average BMI z scores. Among children with above-average BMI z scores at age 7 years, a score increase of 0.5 from ages 7 to 13 years was positively associated with early ischemic stroke in women (HR, 1.10; 95% CI, 1.01-1.20) and in men (HR, 1.08; 95% CI, 1.00-1.16). Similarly, among children with below-average BMI z scores at age 7 years, a score increase of 0.5 from ages 7 to 13 years was positively associated with early ischemic stroke in women (HR, 1.14; 95% CI, 1.06-1.23) and in men (HR, 1.10; 95% CI, 1.04-1.18). Adjusting for birth weight minimally affected the associations.

Conclusions and Relevance

Independent of birth weight, above-average childhood BMI and increases in BMI during childhood are positively associated with early adult ischemic stroke. To avoid the occurrence of early ischemic stroke associated with childhood overweight and obesity, these results suggest that all children should be helped to attain and maintain healthy weights.

Long-term trends in the prevalence of patients hospitalized with ischemic stroke from 1995 to 2010 in Sweden

OBJECTIVE

The prevalence of stroke is expected to increase partly because of prolonged life expectancy in the general population. The objective of this study was to investigate trends in the prevalence of patients hospitalized with ischemic stroke (IS) in Sweden from 1995-2010.

METHODS

The Swedish inpatient and cause-specific death registries were used to estimate the absolute numbers and prevalence of patients who were hospitalized with and survived an IS from 1995-2010.

RESULTS

The overall number of IS increased from 129,418 in 1995 to 148,778 in 2010. In 1995, the prevalence of IS was 189 patients per 10,000 population. An increase in overall prevalence was observed until 2000, and then it remained stable, followed by a decline with an annual percentage change of (APC) -0.8% (95% CI -1.0 to 0.6) and with a final prevalence of 199 patients per 10,000 population in 2010. The prevalence of IS in people aged <45 years increased from 6.4 in 1995 to 7.6 patients per 10,000 population in 2010, with an APC of 2.1% (95% CI 0.9 to 3.4) from 1995-1998 and 0.7% (95% CI 0.6-0.9) from 1998-2010. Among those aged 45-54 years, the prevalence rose through the mid to late 1990s, followed by a slight decrease (APC: -0.7%, 95% CI-1.1 to -0.4) until 2006 and then remained stable with a prevalence of 43.8 patients per 10,000 population in 2010. Among ≥85 years, there was a minor decrease (APC: -0.3%, 95% CI -0.5 to -0.1) in overall prevalence after 2002 from 1481 to 1453 patients per 10,000 population in 2010.

CONCLUSION

The overall prevalence of IS increased until 2000, but then remained stable followed by a slight decline. However, the prevalence of IS in the young increased through the study period. The absolute number of IS survivors has markedly increased, mainly because of demographic changes.

Long-Term Risk of Dementia Among Survivors of Ischemic or Hemorrhagic Stroke

BACKGROUND AND PURPOSE

Stroke is a risk factor for dementia, but the risk of dementia after different stroke types is poorly understood. We examined the long-term risk of dementia among survivors of any first-time stroke and of first-time ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage.

METHODS

We conducted a 30-year nationwide population-based cohort study using data from Danish medical databases (1982-2013) covering all Danish hospitals. We identified 84 220 ischemic stroke survivors, 16 723 intracerebral hemorrhage survivors, 9872 subarachnoid hemorrhage survivors, and 104 303 survivors of unspecified stroke types. Patients were aged ≥18 years and survived for at least 3 months after diagnosis. We formed a comparison cohort from the general population (1 075 588 patients without stroke, matched to stroke patients by age and sex). We computed absolute risks and hazard ratios of dementia up to 30 years after stroke.

RESULTS

The 30-year absolute risk of dementia among stroke survivors was 11.5% (95% confidence interval, 11.2%-11.7%). Compared with the general population, the hazard ratio (95% confidence interval) for dementia among stroke survivors was 1.80 (1.77-1.84) after any stroke, 1.72 (1.66-1.77) after ischemic stroke, 2.70 (2.53-2.89) after intracerebral hemorrhage, and 2.74 (2.45-3.06) after subarachnoid hemorrhage. Younger patients regardless of stroke type faced higher risks of poststroke dementia than older patients. The pattern of hazard ratios by stroke type did not change during follow-up and was not altered appreciably by age, sex, or preexisting diagnoses of vascular conditions.

CONCLUSIONS

Stroke increases dementia risk. Survivors of intracerebral hemorrhage and subarachnoid hemorrhage are at particularly high long-term risk of poststroke dementia.

Global stroke statistics

Background Up to date data on incidence, mortality, and case-fatality for stroke are important for setting the agenda for prevention and healthcare. Aims and/or hypothesis We aim to update the most current incidence and mortality data on stroke available by country, and to expand the scope to case-fatality and explore how registry data might be complementary. Methods Data were compiled using two approaches: (1) an updated literature review building from our previous review and (2) direct acquisition and analysis of stroke events in the World Health Organization (WHO) mortality database for each country providing these data. To assess new and/or updated data on incidence, we searched multiple databases to identify new original papers and review articles that met ideal criteria for stroke incidence studies and were published between 15 May 2013 and 31 May 2016. For data on case-fatality, we searched between 1980 and 31 May 2016. We further screened reference lists and citation history of papers to identify other studies not obtained from these sources. Mortality codes for ICD-8, ICD-9, and ICD-10 were extracted. Using population denominators provided for each country, we calculated both the crude mortality from stroke and mortality adjusted to the WHO world population. We used only the most recent year reported to the WHO for which both population and mortality data were available. Results Fifty-one countries had data on stroke incidence, some with data over many time periods, and some with data in more than one region. Since our last review, there were new incidence studies from 12 countries, with four meeting pre-determined quality criteria. In these four studies, the incidence of stroke, adjusted to the WHO World standard population, ranged from 76 per 100,000 population per year in Australia (2009-10) up to 119 per 100,000 population per year in New Zealand (2011-12), with the latter being in those aged at least 15 years. Only in Martinique (2011-12) was the incidence of stroke greater in women than men. In countries either lacking or with old data on stroke incidence, eight had national clinical registries of hospital based data. Of the 128 countries reporting mortality data to the WHO, crude mortality was greatest in Kazhakstan (in 2003), Bulgaria, and Greece. Crude mortality and crude incidence of stroke were both positively correlated with the proportion of the population aged ≥ 65 years, but not with time. Data on case-fatality were available in 42 studies in 22 countries, with large variations between regions. Conclusions In this updated review, we describe the current data on stroke incidence, case-fatality and mortality in different countries, and highlight the growing trend for national clinical registries to provide estimates in lieu of community-based incidence studies.

Changes in the prevalence of hospitalization and comorbidity in US adults with stroke: A three decade cross-sectional and birth cohort analysis

BACKGROUND AND PURPOSE

Little attention was paid to the transition of care for stroke that may partially explain the long-term trend of stroke rates. We aimed to test the trend of hospitalization attributable to stroke in US adults.

METHODS

Data from National Hospital Discharge Surveys 1980-2010 in patients aged ≥18 (n = 6,527,304) were analyzed to examine the trend of patients with first-list diagnoses of stroke. Stroke comorbidities were classified in stroke patients with second- to seven-listed diagnoses of coronary heart disease, hypertension, diabetes, arrhythmias, or hyperlipidemia. Stroke trends by survey years and birth cohorts were analyzed using univariate, multivariate, and birth cohorts methods.

RESULTS

Of the total study sample, the prevalence of hospitalization due to stroke was 22.99%, 30.00%, and 27.03% in years of 1980-1989, 1990-1999, and 2000-2010 in males, and 17.30%, 22.04%, and 19.34% in females, respectively. Overall, hospitalization rates in stroke patients significantly increased among adults aged <65, and decreased in adults aged ≥65. There was an increase in stroke hospitalization rate in the old adults aged ≥65 in recent birth cohorts. Significant increased trends of comorbid hypertension, diabetes, arrhythmias, and hyperlipidemia were observed from 1980 to 2010.

CONCLUSION

A significant increase in stroke hospitalization rate was observed in adults aged <65 in the past three decades, and in old adults in recent years. Increases in stroke comorbidity rates were observed in all age groups. Findings from the study highlight that both public health and clinical practices face a serious challenge in controlling this unwelcome increased stroke trend.

Increasing Incidence of Hospitalization for Stroke and Transient Ischemic Attack in Young Adults: A Registry-Based Study

Background

Studies have reported increasing incidence of ischemic stroke in adults younger than 50 to 55 years. Information on temporal trends of other stroke subtypes and transient ischemic attack (TIA) is sparse. The aim of this study was to investigate temporal trends of the incidence of hospitalizations for TIA and stroke including sex‐ and subtype‐specific trends in young adults aged 15 to 30 years.

Methods and Results

From the Danish National Patient Register, we identified all cases of first‐ever stroke and TIA (age 15–30 years) in Denmark, who were hospitalized during the study period of 1994 to 2012. Incidence rates and estimated annual percentage changes (EAPCs) were estimated by using Poisson regression. During the study period, 4156 cases of first‐ever hospitalization for stroke/TIA were identified. The age‐standardized incidence rates of hospitalizations for stroke increased significantly (EAPC 1.83% [95% CI 1.11–2.55%]) from 11.97/100 000 person‐years (PY) in 1994 to 16.77/100 000 PY in 2012. TIA hospitalizations increased from 1.93/100 000 PY in 1994 to 5.81/100 000 PY in 2012 and after 2006 more markedly in men than in women (EAPC 16.61% [95% CI 10.45–23.12%]). The incidence of hospitalizations for ischemic stroke was markedly lower among men, but increased significantly from 2006 (EAPC 14.60% [95% CI 6.22–23.63%]). The incidences of hospitalizations for intracerebral hemorrhage and subarachnoid hemorrhage remained stable during the study period.

Conclusions

The incidence rates of first‐time hospitalizations for ischemic stroke and TIA in young Danish adults have increased substantially since the mid 1990s. The increase was particularly prominent in the most recent years.

Validity of Diagnostic Codes for Acute Stroke in Administrative Databases: A Systematic Review

OBJECTIVE

To conduct a systematic review of studies reporting on the validity of International Classification of Diseases (ICD) codes for identifying stroke in administrative data.

METHODS

MEDLINE and EMBASE were searched (inception to February 2015) for studies: (a) Using administrative data to identify stroke; or (b) Evaluating the validity of stroke codes in administrative data; and (c) Reporting validation statistics (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), or Kappa scores) for stroke, or data sufficient for their calculation. Additional articles were located by hand search (up to February 2015) of original papers. Studies solely evaluating codes for transient ischaemic attack were excluded. Data were extracted by two independent reviewers; article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool.

RESULTS

Seventy-seven studies published from 1976-2015 were included. The sensitivity of ICD-9 430-438/ICD-10 I60-I69 for any cerebrovascular disease was ≥ 82% in most [≥ 50%] studies, and specificity and NPV were both ≥ 95%. The PPV of these codes for any cerebrovascular disease was ≥ 81% in most studies, while the PPV specifically for acute stroke was ≤ 68%. In at least 50% of studies, PPVs were ≥ 93% for subarachnoid haemorrhage (ICD-9 430/ICD-10 I60), 89% for intracerebral haemorrhage (ICD-9 431/ICD-10 I61), and 82% for ischaemic stroke (ICD-9 434/ICD-10 I63 or ICD-9 434&436). For in-hospital deaths, sensitivity was 55%. For cerebrovascular disease or acute stroke as a cause-of-death on death certificates, sensitivity was ≤ 71% in most studies while PPV was ≥ 87%.

CONCLUSIONS

While most cases of prevalent cerebrovascular disease can be detected using 430-438/I60-I69 collectively, acute stroke must be defined using more specific codes. Most in-hospital deaths and death certificates with stroke as a cause-of-death correspond to true stroke deaths. Linking vital statistics and hospitalization data may improve the ascertainment of fatal stroke.