Myocarditis after BNT162b2 mRNA Vaccine against Covid-19 in Israel.

BACKGROUND: Approximately 5.1 million Israelis had been fully immunized against coronavirus disease 2019 (Covid-19) after receiving two doses of the BNT162b2 messenger RNA vaccine (Pfizer-BioNTech) by May 31, 2021. After early reports of myocarditis during adverse events monitoring, the Israeli Ministry of Health initiated active surveillance. METHODS: We retrospectively reviewed data obtained from December 20, 2020, to May 31, 2021, regarding all cases of myocarditis and categorized the information using the Brighton Collaboration definition. We analyzed the occurrence of myocarditis by computing the risk difference for the comparison of the incidence after the first and second vaccine doses (21 days apart); by calculating the standardized incidence ratio of the observed-to-expected incidence within 21 days after the first dose and 30 days after the second dose, independent of certainty of diagnosis; and by calculating the rate ratio 30 days after the second dose as compared with unvaccinated persons. RESULTS: Among 304 persons with symptoms of myocarditis, 21 had received an alternative diagnosis. Of the remaining 283 cases, 142 occurred after receipt of the BNT162b2 vaccine; of these cases, 136 diagnoses were definitive or probable. The clinical presentation was judged to be mild in 129 recipients (95%); one fulminant case was fatal. The overall risk difference between the first and second doses was 1.76 per 100,000 persons (95% confidence interval [CI], 1.33 to 2.19), with the largest difference among male recipients between the ages of 16 and 19 years (difference, 13.73 per 100,000 persons; 95% CI, 8.11 to 19.46). As compared with the expected incidence based on historical data, the standardized incidence ratio was 5.34 (95% CI, 4.48 to 6.40) and was highest after the second dose in male recipients between the ages of 16 and 19 years (13.60; 95% CI, 9.30 to 19.20). The rate ratio 30 days after the second vaccine dose in fully vaccinated recipients, as compared with unvaccinated persons, was 2.35 (95% CI, 1.10 to 5.02); the rate ratio was again highest in male recipients between the ages of 16 and 19 years (8.96; 95% CI, 4.50 to 17.83), with a ratio of 1 in 6637. CONCLUSIONS: The incidence of myocarditis, although low, increased after the receipt of the BNT162b2 vaccine, particularly after the second dose among young male recipients. The clinical presentation of myocarditis after vaccination was usually mild.

Vaccine Coverage Associated With Ending a Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Wave: A Retrospective Longitudinal Analysis.

BACKGROUND: Two SARS-CoV-2 waves in Israel ended while a substantial number of individuals remained unvaccinated or partially vaccinated. The indirect protective effect of the first BNT162b2 vaccination campaign in Israel was evaluated between 22 December 2020 and 18 May 2021. METHODS: The daily percentage of new polymerase chain reaction (PCR)-confirmed SARS-CoV-2 cases among unvaccinated individuals was analyzed for trends. Major shifts were identified using piecewise linear regression analysis. At these shifts, the percentage of naturally vaccinated (past SARS-CoV-2 cases) and the percentage of actively vaccinated (by inoculation) individuals were weighted and summed to determine the percentage of natural and active vaccination (NAV). RESULTS: A first decline among unvaccinated individuals occurred during a lockdown period, when the percentage of NAV was 8.16%. The major decline occurred after the end of the lockdown when the percentage of NAV reached 52.05%. SARS-CoV-2 cases ultimately declined among unvaccinated individuals when the percentage of NAV reached 63.55%. During the study period, the Alpha variant was prevalent and the use of nonpharmaceutical interventions, including social distancing, existed to varying degrees. CONCLUSIONS: The vaccination campaign played a major role in the decline of SARS-CoV-2 infection among unvaccinated individuals, leading to the end of the first 2021 SARS-CoV-2 wave (Alpha variant) in Israel. Infection in unvaccinated individuals stopped when two-thirds of the population were naturally or actively vaccinated. Any change in characteristics of the virus or the population can lead to a new outbreak.

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.

Effectiveness of BNT162b2 Vaccine against Omicron Variant Infection among Children 5-11 Years of Age, Israel.

We assessed effectiveness of the BNT162b2 vaccine against infection with the B.1.1.529 (Omicron) variant (mostly BA.1 subvariant), among children 5-11 years of age in Israel. Using a matched case-control design, we matched SARS-CoV-2-positive children (cases) and SARS-CoV-2-negative children (controls) by age, sex, population group, socioeconomic status, and epidemiologic week. Vaccine effectiveness estimates after the second vaccine dose were 58.1% for days 8-14, 53.9% for days 15-21, 46.7% for days 22-28, 44.8% for days 29-35, and 39.5% for days 36-42. Sensitivity analyses by age group and period demonstrated similar results. Vaccine effectiveness against Omicron infection among children 5-11 years of age was lower than vaccine efficacy and vaccine effectiveness against non-Omicron variants, and effectiveness declined early and rapidly.

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.

Effectiveness of BNT162b2 Vaccine Booster against SARS-CoV-2 Infection and Breakthrough Complications, Israel.

We estimated vaccine effectiveness (VE) of the BNT162b2 (Pfizer-BioNTech, https://www.pfizer.com) booster dose against SARS-CoV-2 infection and reduction of complications (hospitalization, severe disease, and death) among breakthrough cases in persons in Israel >16 years of age for <20 weeks. VE estimates reached 96.8% (95% CI 96.0%-97.5%) for persons 16-59 years of age and 93.1% (95% CI 91.8%-94.2%) for persons >60 years of age on week 3. VE estimates remained at these levels for 8 weeks in the 16-59 age group and 11 weeks in those >60. A slow decline followed, becoming more pronounced in the last 2-3 weeks of evaluation. Estimates in the last week of evaluation were 77.6% (95% CI 68.4%-84.2%) and 61.3% (52.5%-68.4%) for persons 16-59 years and >60 years, respectively. The more pronounced VE decline coincided with rapid increase in Omicron variant activity. Rate reduction of breakthrough complications remained moderate to high throughout the evaluation.

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.

Incidence and risk factors of mental disorders in the elderly: The European MentDis_ICF65+ study.

OBJECTIVE: While incidence rates of depression and anxiety disorders in the elderly have been comprehensively investigated, the incidence rates of other mental disorders have rarely been researched. The incidence rate and predictors of various mental disorders in the elderly were evaluated in different European and associated countries. METHODS: A cross-sectional and longitudinal multi-centre survey of Diagnostic and Statistical Manual of Mental Disorders (4th ed.) diagnoses was conducted in different European and associated countries (Germany, Italy, Spain, Switzerland, the United Kingdom and Israel) to collect data on the prevalence and incidence of mental disorders in the elderly. The sample size of the longitudinal wave was N = 2592 elderly. RESULTS: The overall 1-year incidence rate for any mental disorder in the elderly is 8.65%. At 5.18%, any anxiety disorder had the highest incidence rate across all diagnostic groups. The incidence rate for any affective disorder was 2.97%. The lowest incidence rates were found for agoraphobia (1.37%) and panic disorder (1.30%). Risk factors for the development of any mental disorder were never having been married, no religious affiliation, a higher number of physical illnesses and a lower quality of life. CONCLUSION: In comparison to other studies, lower incidence rates for any affective disorder and middle-range incidence for any anxiety disorder were found. To the authors' knowledge, no prior studies have reported 1-year incidence rates for somatoform disorder, bipolar disorder and substance misuse in community-dwelling elderly. These findings indicate the need to raise awareness of psychosocial problems in the elderly and to ensure adequate availability of mental health services.

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.

Effectiveness of BNT162b2 Vaccine in Adolescents during Outbreak of SARS-CoV-2 Delta Variant Infection, Israel, 2021.

In Israel, the BNT162b2 vaccine against severe acute respiratory syndrome coronavirus 2 was approved for use in adolescents in June 2021, shortly before an outbreak of B.1.617.2 (Delta) variant-dominant infection. We evaluated short-term vaccine effectiveness and found the vaccine to be highly effective among this population in this setting.

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.

Under-diagnosis of SARS-CoV-2 infections among children aged 0-15 years, a nationwide seroprevalence study, Israel, January 2020 to March 2021.

Until recently, children and adolescents were not eligible for COVID-19 vaccination. They may have been a considerable source of SARS-CoV-2 spread. We evaluated SARS-CoV-2 IgG antibody seroprevalence in Israeli children aged 0-15 years from January 2020 to March 2021. Seropositivity was 1.8-5.5 times higher than COVID-19 incidence rates based on PCR testing. We found that SARS-CoV-2 infection among children is more prevalent than previously thought and emphasise the importance of seroprevalence studies to accurately estimate exposure.

Quality of life, level of functioning, and its relationship with mental and physical disorders in the elderly: results from the MentDis_ICF65+ study.

BACKGROUND: An ageing population worldwide needs to investigate quality of life (QoL) and level of functioning (LoF) in the elderly and its associated variables. We aimed to study the relationship between Quality of Life (QoL) and Level of Functioning (LoF) in an elderly population in Europe. METHOD: As part of the Ment_Dis65+ European Project, 3142 community-dwelling adults aged 65-84 years in six countries were assessed by using the adaptation for the elderly of the Composite International Diagnostic Interview (CIDI65+) to provide psychiatric diagnosis according to the International Classification of Diseases (10th edition) (ICD-10 Classification of Mental and Behavioural Disorders). Socio-demographic and clinical interviews, and two self-report tools, the World Health Organization QoL assessment (WHO QoL BREF), to assess QoL, and the WHO Disability Assessment Schedule -II (WHODAS-II), to assess LoF, were also administered. RESULTS: Most subjects reported good levels of QoL (56.6%) and self-rated health (62%), with no or mild disability (58.8%). There was a linear decrease of the QoL and the LoF by increase of age. Elderly with ICD-10 mental disorder (e.g. somatoform, affective and anxiety disorders) had poorer QoL and lower LoF. There were a number of predictors of lower levels of QoL and disability, including both socio-demographic variables (e.g. male gender, increase in age, poor financial situation, retirement, reduced number of close significant others), ICD-10 psychiatric diagnosis (mainly anxiety, somatoform disorders) and presence of medical disorders (mainly heart and respiratory diseases). CONCLUSIONS: The study indicates that QoL and LoF were quite acceptable in European elderly people. A series of variables, including psychiatric and somatic disorders, as well as socio-demographic factor influenced in a negative way both QoL and LoF. More specific links between mental health, social and health services dedicated to this segment of the population, should be implemented in order to provide better care for elderly people with conditions impacting their QoL and functioning.

[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.

Anxiety Disorders in Old Age: Psychiatric Comorbidities, Quality of Life, and Prevalence According to Age, Gender, and Country.

OBJECTIVES: Previous estimates of the prevalence of anxiety disorders in late life vary greatly due to the lack of reliable diagnostic tools. This MentDis_ICF65+ study assessed 12-month prevalence rates of anxiety disorders and age- and gender-related differences in comorbidities, as well as impact on quality of life. DESIGN: The study used a cross-sectional multicenter survey. PARTICIPANTS: The study sample comprised 3,142 men and women aged 65 to 84 years, living in five European countries and Israel. MEASUREMENTS: Anxiety disorders were assessed using computer-assisted face-to-face interviews with an age-appropriate diagnostic interview (CIDI65+). RESULTS: The prevalence of anxiety disorders was 17.2%. Agoraphobia was the most frequent disorder (4.9%), followed by panic disorder (3.8%), animal phobia (3.5%), general anxiety disorder (3.1%), post-traumatic stress disorder (1.4%), social phobia (1.3%), and obsessive-compulsive disorder (0.8%). The prevalence rate of any anxiety disorder dropped by 40% to 47% in adults aged 75-84 years compared with those aged 65-74 years. Women were twice as likely to present with agoraphobia or general anxiety disorder as men. Only panic disorder and phobia were associated with comorbid major depression. The negative relationship with quality of life was limited to agoraphobia and generalized anxiety disorder. CONCLUSIONS: The age-appropriate CIDI65+ led to higher prevalence rates of anxiety disorders in the elderly, yet to weaker associations with comorbidities and impaired quality of life compared with previous studies.

Predisposing, enabling, and need factors of service utilization in the elderly with mental health problems.

ABSTRACTBackground:Empirical data on the use of services due to mental health problems in older adults in Europe is lacking. The objective of this study is to identify factors associated with service utilization in the elderly. METHODS: As part of the MentDis_ICF65+ study, N = 3,142 people aged 65-84 living in the community in six European and associated countries were interviewed. Based on Andersen's behavioral model predisposing, enabling, and need factors were analyzed with logistic regression analyses. RESULTS: Overall, 7% of elderly and 11% of those with a mental disorder had used a service due to mental health problems in the last 12 months. Factors significantly associated with underuse were male sex, lower education, living in the London catchment area, higher functional impairment and more comorbid mental disorders. The most frequently reported barrier to service use was personal beliefs, e.g. "I can deal with my problem on my own" (90%). CONCLUSION: Underutilization of mental health services among older people in the European community is common and interventions are needed to achieve an adequate use of services.

Prevalence of mental disorders in elderly people: the European MentDis_ICF65+ study.

BACKGROUND: Except for dementia and depression, little is known about common mental disorders in elderly people. AIMS: To estimate current, 12-month and lifetime prevalence rates of mental disorders in different European and associated countries using a standardised diagnostic interview adapted to measure the cognitive needs of elderly people. METHOD: The MentDis_ICF65+ study is based on an age-stratified, random sample of 3142 older men and women (65-84 years) living in selected catchment community areas of participating countries. RESULTS: One in two individuals had experienced a mental disorder in their lifetime, one in three within the past year and nearly one in four currently had a mental disorder. The most prevalent disorders were anxiety disorders, followed by affective and substance-related disorders. CONCLUSIONS: Compared with previous studies we found substantially higher prevalence rates for most mental disorders. These findings underscore the need for improving diagnostic assessments adapted to the cognitive capacity of elderly people. There is a need to raise awareness of psychosocial problems in elderly people and to deliver high-quality mental health services to these individuals.

Study approach and field work procedures of the MentDis_ICF65+ project on the prevalence of mental disorders in the older adult European population.

BACKGROUND: This study describes the study approach and field procedures of the MentDis_ICF65+ study, which aims to assess the prevalence of mental disorders in older adults. METHODS: An age-appropriate version of the Composite International Diagnostic Interview (CIDI65+) was developed and tested with regard to its feasibility and psychometric properties in a pre-test and pilot phase. In the cross-sectional survey an age-stratified, random sample of older adults (65-84 years) living in selected catchment areas of five European countries and Israel was recruited. RESULTS: N = 3142 participants (mean age 73.7 years, 50.7% female) took part in face-to-face interviews. The mean response rate was 20% and varied significantly between centres, age and gender groups. Sociodemographic differences between the study centres appeared for the place of birth, number of grandchildren, close significants, retirement and self-rated financial situation. The comparison of the MentDis_ICF65+ sample with the catchment area and country population of the study centres revealed significant differences, although most of these were numerically small. CONCLUSIONS: The study will generate new information on the prevalence of common mental disorders among older adults across Europe using an age-appropriate, standardized diagnostic instrument and a harmonized approach to sampling. Generalizability of the findings and a potentially limited representativeness are discussed.