Age-dependent seasonality in the incidence of stroke: A 21-year population-based study.

INTRODUCTION: Seasonality in the incidence of stroke has been examined in numerous studies, yet data on whether it differs with age are limited. To fill this gap, we utilized a largescale dataset from Israel. PATIENTS AND METHODS: We retrieved data of all hospitalizations for ischemic stroke (IS), transient ischemic attack (TIA) and intra cerebral hemorrhage (ICH) from 2000 to 2020. We maintained separate datasets for IS/TIA and ICH, divided into five age groups: 18-49, 50-59, 60-69, 70-79, and 80+. We modeled the monthly incidence using a generalized additive model. The seasonal effect was defined by the rate ratio (RR) of each month compared to the annual mean. RESULTS: The analysis included 317,586 and 23,789 events of IS/TIA and ICH respectively. We found an interaction between age and seasonality, accounting for a phase shift with age in the seasonal pattern of IS/TIA incidence. For cases under 70 years, the peak was during summertime and the RRs increased with decreasing age, reaching 1.11 (95% CI 1.09-1.13) at the youngest age group. In contrast, among the elderly, a winter peak was observed and the RRs increased with age to 1.07 (95% CI 1.06-1.08) at the oldest age group. For ICH, a winter/autumn peak was identified and the RRs increased with age to 1.20 (95% CI 1.16-1.24). CONCLUSIONS: Our finding of age-dependent seasonal patterns in the occurrence of stroke, suggests closer monitoring of cardiovascular risk factors during wintertime among elderly individuals. The mechanism governing the seasonal phase shift with age in IS/TIA incidence, requires further investigation.

An Increased Risk for Ischemic Stroke in the Short-Term Period following COVID-19 Infection: A Nationwide Population-Based Study.

INTRODUCTION: The association disclosed between coronavirus disease 2019 (COVID-19) infection and ischemic stroke (IS) raises concern. The exact risk periods, which were not consistent between studies, require further investigation. METHODS: We linked two national databases: the COVID-19 database and the Israeli National Stroke Registry. The self-controlled case series method was used to estimate the association between COVID-19 infection and a first IS. The study population included all Israeli residents who had both a first IS event and a first COVID-19 diagnosis during 2020. The date of the PCR test served to define the day of exposure, and the 28 days following it were categorized into three risk periods: days 1-7, 8-14, and 15-28. A relative incidence (RI) with a 95% confidence interval (95% CI) was calculated based on the incidence rate of events in a post-exposure period, compared to the incidence rate in a control period. RESULTS: From January 1, 2020, to December 31, 2020, 308,015 Israelis aged 18+ were diagnosed with COVID-19 and 9,535 were diagnosed with a first IS. Linking the two databases, 555 persons had both diagnoses during 2020. The mean age of the study population was 71.5 ± 13.7, 55.1% were males, 77.8% had hypertension, 73.7% had hyperlipidemia, 51.9% had diabetes, and 28.5% had ischemic heart disease. Comparing the risk period and the control period, we found a very similar distribution of the cardiovascular risk factors. The risk for an acute IS was 3.3-fold higher in the first week following COVID-19 diagnosis, compared with a control period (RI = 3.3; 95% CI: 2.3-4.6). The RI among males (RI = 4.5; 95% CI: 2.9-6.8) was 2.2-fold higher compared to females. The increased risk did not last beyond the first week following exposure. CONCLUSION: Physicians should be aware of the elevated risk for IS among patients experiencing COVID-19, particularly among men with high burden of cardiovascular risk factors.

Adolescent Hypertension Is Associated With Stroke in Young Adulthood: A Nationwide Cohort of 1.9 Million Adolescents.

BACKGROUND: Adult hypertension is a well-established risk factor for stroke in young adults (aged <55 years), and the effects are even more deleterious than at an older age. However, data are limited regarding the association between adolescent hypertension and the risk of stroke in young adulthood. METHODS: A nationwide, retrospective cohort study of adolescents (aged 16-19 years) who were medically evaluated before compulsory military service in Israel during 1985 to 2013. For each candidate for service, hypertension was designated after constructed screening, and the diagnosis was confirmed through a comprehensive workup process. The primary outcome was ischemic and hemorrhagic stroke incidence as registered at the national stroke registry. Cox proportional-hazards models were used. We conducted sensitivity analyses by excluding people with a diabetes diagnosis at adolescence or a new diabetes diagnosis during the follow-up period, analysis of adolescents with overweight, and adolescents with baseline unimpaired health status. RESULTS: The final sample included 1 900 384 adolescents (58% men; median age, 17.3 years). In total, 1474 (0.08%) incidences of stroke (1236 [84%] ischemic) were recorded, at a median age of 43 (interquartile range, 38-47) years. Of these, 18 (0.35%) occurred among the 5221 people with a history of adolescent hypertension. The latter population had a hazard ratio of 2.4 (95% CI, 1.5-3.9) for incident stroke after adjustment for body mass index and baseline sociodemographic factors. Further adjustment for diabetes status yielded a hazard ratio of 2.1 (1.3-3.5). We found similar results when the outcome was ischemic stroke with a hazard ratio of 2.0 (1.2-3.5). Sensitivity analyses for overall stroke, and ischemic stroke only, yielded consistent findings. CONCLUSIONS: Adolescent hypertension is associated with an increased risk of stroke, particularly ischemic stroke, in young adulthood.

Particulate Air Pollution Exposure and Stroke among Adults in Israel.

Stroke is the second most common cause of death and disability in the world. Many studies have found fine particulate matter (PM2.5) exposure to be associated with an increased risk of atherosclerotic cardiovascular disease, mostly focusing on ischemic heart disease and acute myocardial infarction. In a national analysis conducted in Israel-an area with unique climate conditions and high air pollution levels, we estimated the association between short-term PM2.5 exposure and ischemic stroke, intracerebral hemorrhage (ICH), or transient ischemic attacks (TIA). Using the Israeli National Stroke Registry, we obtained information on all stroke cases across Israel in 2014-2018. We obtained daily PM2.5 exposures from spatiotemporally resolved exposure models. We restricted the analytical data to days in which PM2.5 levels did not exceed the Israeli 24 h standard (37.5 µg/m3). We repeated the analysis with a stratification by sociodemographic characteristics and comorbidities. For all outcomes, the exposure-response curves were nonlinear. PM2.5 exposure was associated with a higher ischemic stroke risk, with larger effect estimates at higher exposure levels. Although nonsignificant, the exposure-response curve for TIA was similar. The associations with ICH were nonsignificant throughout the PM2.5 exposure distribution. The associations with ischemic stroke/TIA were larger among women, non-Jewish individuals, older adults, and individuals with diabetes, hypertension, and ischemic heart disease. In conclusion, short-term PM2.5 exposure is associated with a higher risk for ischemic stroke and possibly TIA, even when PM2.5 concentrations do not exceed the Israeli air quality guideline threshold. Vulnerability to the air pollution effects differed by age, sex, ethnicity, and comorbidities.

The contribution of potentially modifiable risk factors to acute ischemic stroke burden - Comparing young and older adults.

Stroke is a leading cause of death and disability. In order to estimate the contribution of five modifiable risk factors to acute ischemic stroke (AIS) incidence in Israel, we conducted a case-control study based on first AIS cases aged 21-90 reported to the Israeli National Stroke Registry during 2014-2015, and controls from a national health survey conducted between 2013 and 2015. We calculated the population attributable risk (PAR) of each risk factor and the combined PAR for all risk factors (hypertension, diabetes, current smoking, obesity and hyperlipidemia), in all study population and by subgroups of young adults (age < 55) and older adults (age ≥ 55). The final analysis included 571, 577 and 500 matched pairs for all study population, young adults and older adults, respectively. Among young adults, current smoking and hypertension were the two most contributing risk factors for AIS, accounting for 33.6% (95% CI 27.3-39.9) and 28.9% (95% CI 22.1-35.7) of AIS cases, respectively. Among older adults, hypertension was the single most contributing risk factor for AIS and diabetes was the second most contributing risk factor for AIS, accounting for 64.9% (95% CI 57.3-72.5) and 25.7% (95% CI 17.5-33.9) of AIS cases, respectively. The combined PAR was significantly lower among young adults (PAR = 67.9%), compared with older adults (PAR = 80.7%). The combined PAR for all study population was 80.1% (95% CI 74.0-86.2), indicating that five common and modifiable risk factors explain ~80% of AIS incidence in Israel. Primary prevention strategies targeting these risk factors have the potential to drastically reduce stroke related morbidity and mortality.

Diabetes associated risk for mortality increases with time among first stroke survivors - Findings from the Israeli National Stroke Registry.

BACKGROUND: Diabetes is a major risk factor for ischemic stroke and may affect post-stroke survival. Previous large scale studies of long-term post-stroke survival are limited and most of them excluded older patients from the study population. OBJECTIVES: To compare the risk factors and sociodemographic characteristics between first ischemic stroke cases with and without diabetes and to assess the mortality risk associated with diabetes. METHODS: Using population-based National Stroke Registry in Israel, all patients hospitalized for a first event of ischemic stroke between the years 2014-2018 were followed for all-cause mortality. Chi-square analysis was used to compare the differences in risk factors, sociodemographic profile and cumulative mortality between patients with and without diabetes. Cox proportional hazards models were used to estimate the hazard ratio for mortality in selected timeframes. RESULTS: Among 41,639 patients with a first event of ischemic stroke, 44.5% were previously diagnosed with diabetes. Diabetic patients were more likely to be males, members of the Arab ethnic group, with lower socioeconomic status and a higher prevalence of cardiovascular comorbidities, anemia, leukocytosis and abnormal kidney function. Diabetes was associated with a higher mortality risk in the first year and long term, but not in the first month following stroke. Diabetes-associated mortality risk interacted with time and age, was higher in younger age and increased with time. CONCLUSIONS: Our findings suggest that diabetes is associated with a higher prevalence of comorbidities among patients with first ischemic stroke and with a higher risk for mortality in the mid and long term, which is more profound in younger age.

Reduction in Acute Stroke Admissions during the COVID-19 Pandemic: Data from a National Stroke Registry.

INTRODUCTION: The COVID-19 pandemic overwhelmed health-care systems worldwide, and medical care for other acute diseases was negatively impacted. We aimed to investigate the effect of the COVID-19 outbreak on admission rates and in-hospital care for acute stroke and transient ischemic attack (TIA) in Israel, shortly after the start of the pandemic. METHODS: We conducted a retrospective observational study, based on data reported to the Israeli National Stroke Registry from 7 tertiary hospitals. All hospital admissions for acute stroke or TIA that occurred between January 1 and April 30, 2020 were included. Data were stratified into 2 periods according to the timing of COVID-19 restrictions as follows: (1) "pre-pandemic" - January 1 to March 7, 2020 and (2) "pandemic" - March 8 to April 30, 2020. We compared the weekly counts of hospitalizations between the 2 periods. We further investigated changes in demographic characteristics and in some key parameters of stroke care, including the percentage of reperfusion therapies performed, time from hospital arrival to brain imaging and to thrombolysis, length of hospital stay, and in-hospital mortality. RESULTS: 2,260 cases were included: 1,469 in the pre-COVID-19 period and 791 in the COVID-19 period. Hospital admissions significantly declined between the 2 periods, by 48% for TIA (rate ratio [RR] = 0.52; 95% CI 0.43-0.64) and by 29% for stroke (RR = 0.71; 95% CI 0.64-0.78). No significant changes were detected in demographic characteristics and in most parameters of stroke management. While the percentage of reperfusion therapies performed remained unchanged, the absolute number of patients treated with reperfusion therapies seemed to decrease. Higher in-hospital mortality was observed only for hemorrhagic stroke. CONCLUSION: The marked decrease in admissions for acute stroke and TIA, occurring at a time of a relatively low burden of COVID-19, is of great concern. Public awareness campaigns are needed as patients reluctant to seek urgent stroke care are deprived of lifesaving procedures and secondary prevention treatments.

Body Mass Index in 1.9 Million Adolescents and Stroke in Young Adulthood.

Background and Purpose: There is a continuous rise in the prevalence of adolescent obesity and incidence of stroke among young adults in many Western countries, but the association between them is unclear. Methods: A nationwide population-based study of 1 900 384 Israeli adolescents (58% men; mean age, 17.3 years) who were evaluated before mandatory military service during 1985 and 2013. Body mass index was classified according to the US Center for Disease Control and Prevention percentiles. Primary outcome was a first stroke event as recorded by the Israeli National Stroke Registry between 2014 and 2018. Cox proportional hazard models were applied. Results: There were 1088 first stroke events (921 ischemic and 167 hemorrhagic; mean diagnosis age, 41.0 years). Adolescent body mass index was significantly associated with a graded increase in the risk for any stroke, ischemic stroke, but less so with hemorrhagic stroke. The hazard ratios for the first ischemic stroke event were 1.4 (95% CI, 1.2­1.6), 2.0 (95% CI, 1.6­2.4), and 3.4 (95% CI, 2.7­4.3) for the 50th to 84th percentile, overweight and obese groups, respectively, after adjustment for sex, age, and sociodemographic confounders with the 5th to 49th body mass index percentile group as the reference. The respective hazard ratios after further adjustment for diabetes status were 1.3 (1.1­1.5), 1.6 (1.3­2.0), and 2.4 (1.9­3.1). Results persisted when the cohort was divided by diabetes status and when ischemic stroke before age 30 was the outcome. Conclusions: High adolescent body mass index was associated with ischemic stroke in young adults with or without diabetes. The rising prevalence of adolescent obesity may increase the future burden of stroke in young adults.

[THE ISRAELI NATIONAL STROKE REGISTRY - A TOOL FOR MONITORING MORBIDITY AND ACUTE STROKE CARE IN ISRAEL].

BACKGROUND: Stroke is a leading cause of death and disability worldwide. Due to the high burden caused by stroke, the Israeli Ministry of Health initiated a national program for the treatment and prevention of stroke, including the establishment of an Israeli National Stroke Registry (INSR). In this article we will demonstrate the use of the INSR as a tool for monitoring the treatment of acute cerebrovascular events (stroke or transient ischemic attack). OBJECTIVES: 1. Assessing incidence rates of acute cerebrovascular events in Israel for the total population and by gender and ethnic group separately. 2. Presenting trends in a number of key indicators related to acute stroke care. METHODS: The INSR is based on data retrieval from hospital electronic medical records of all adult cases discharged with acute cerebrovascular diagnosis from January 1, 2014 on. Included in the current analysis were all cases reported to the INSR until June 31, 2017. RESULTS: The average annual incidence rate of cerebrovascular events in Israel was 3.2 cases per 1,000 people. Age-adjusted rates were significantly higher among Arabs, compared with the Jewish population. From 2014 to 2017 there was a moderate increase in the percentage of arrival by ambulance: from 43.2% to 49.0% and a significant increase in the percentage of head and neck vascular imaging performed: from 50.0% to 72.5%. Between 2014 and 2016 there was a significant increase in the percentage of t-PA administration, and in 2016-2017 the rates stabilized at 9.2%. The proportion of patients hospitalized in neurological wards was 38.0% - a slight increase from 35.0% in 2014. CONCLUSIONS: The INSR is an effective tool for monitoring morbidity and acute stroke care in Israel. Actions should be taken in order to raise public awareness of stroke warning signs and the establishment of stroke units with skilled multidisciplinary teams should become a priority. DISCUSSION: Compared with other western countries, rates of t-PA administration and arrival by ambulance in Israel are slightly low, rates of hospitalization in the neurological ward are significantly lower, and the lack of stroke units is most prominent.

Cancer Risk Among Children Undergoing Renal Replacement Therapy: Results From the Israel National Renal Replacement Therapy Registry, 1990-2012.

BACKGROUND: Patients with end-stage renal disease who undergo chronic renal replacement therapy (RRT) have a higher incidence of cancer. A limited number of studies addressed the risk for cancer in children exposed to RRT. The purpose of the present study was to examine whether children undergoing RRT in Israel are at increased risk for all-site and specific cancers. SUBJECTS AND METHODS: The study population comprised 674 children 0 to 19 years of age who were registered between January 1990 and December 2012 in the Israel National Renal Replacement Therapy Registry. The Registry database was linked with the Israel National Cancer Registry to trace cancer incidence. Variables associated with malignancy were estimated by univariate analysis. Standardized incidence ratios for cancer were calculated using the general Israel population 0 to 15 years of age, for the corresponding years 1990-2012, as a reference. RESULTS: Seventeen children developed cancer during the follow-up period. Younger age at RRT initiation was the only variable associated with malignancy in the univariate analysis (hazard ratio, 0.91; 95% confidence interval, 0.84-0.99; P=0.03). Cancer incidence was 6.7-fold higher among children undergoing RRT than the general population. CONCLUSIONS: Children treated by chronic RRT have a higher incidence of cancer than their peers, and therefore should be followed closely.

Mortality and cancer incidence among patients treated with recombinant growth hormone during childhood in Israel.

CONTEXT: The inconclusive evidence regarding long-term safety of recombinant human growth hormone (rhGH) therapy underlines the need for long-term large-scale cohorts. OBJECTIVE: To assess long-term mortality and cancer incidence among patients treated with rhGH during childhood in Israel. DESIGN: A population-based cohort study. SETTING: Data were retrieved from a national register established in 1988. Mortality data from the national population register were available through 31 December 2014. Data on cancer incidence from the national cancer registry were available through 31 December 2012. PARTICIPANTS: All patients ≤19 years approved for rhGH treatment during 1988-2009 were included. Patients were assigned to three risk categories, according to the underlying condition leading to growth disorder. MAIN OUTCOME MEASURES: All-cause mortality and cancer incidence rates were calculated, based on person-years at risk. Standardized mortality ratios (SMRs) and standardized incidence ratios (SIRs) were calculated, using the Israeli general population as a reference. RESULTS: Included were 1687 patients assigned to the low-risk category and 440 patients assigned to the intermediate-risk category. In the low-risk category, all-cause mortality and cancer incidence were not significantly different than expected (SMR 0·81, 95% CI 0·22-2·08 and SIR 0·76, 95% CI 0·09-2·73). In the intermediate-risk category, all-cause mortality and cancer incidence were significantly higher than expected (SMR 4·05, 95% CI 1·62-8·34 and SIR 4·52, 95% CI 1·22-11·57). CONCLUSIONS: No increased risk of mortality or cancer incidence was found in low-risk patients treated with rhGH during childhood. Patients with prior risk factors were at higher risk of both mortality and cancer.