Contribution Of Various Risk Factors Research Articles

Underlying trend, seasonality, prediction, forecasting and the contribution of risk factors: an analysis of globally reported cases of Middle East Respiratory Syndrome Coronavirus.

This study set out to identify and analyse trends and seasonal variations of monthly global reported cases of the Middle East respiratory syndrome coronavirus (MERS-CoV). It also made a prediction based on the reported and extrapolated into the future by forecasting the trend. Finally, the study assessed contributions of various risk factors in the reported cases. The motivation for this study is that MERS-CoV remains among the list of blueprint priority and potential pandemic diseases globally. Yet, there is a paucity of empirical literature examining trends and seasonality as the available evidence is generally descriptive and anecdotal. The study is a time series analysis using monthly global reported cases of MERS-CoV by the World Health Organisation between January 2015 and January 2018. We decomposed the series into seasonal, irregular and trend components and identified patterns, smoothened series, generated predictions and employed forecasting techniques based on linear regression. We assessed contributions of various risk factors in MERS-CoV cases over time. Successive months of the MERS-CoV cases suggest a significant decreasing trend (P = 0.026 for monthly series and P = 0.047 for Quarterly series). The MERS-CoV cases are forecast to wane by end 2018. Seasonality component of the cases oscillated below or above the baseline (the centred moving average), but no association with the series over time was noted. The results revealed contributions of risk factors such as camel contact, male, old age and being from Saudi Arabia and Middle East regions to the overall reported cases of MERS-CoV. The trend component and several risk factors for global MERS-CoV cases, including camel contact, male, age and geography/region significantly affected the series. Our statistical models appear to suggest significant predictive capacity and the findings may well inform healthcare practitioners and policymakers about the underlying dynamics that produced the globally reported MERS-CoV cases.

Inferring the risk factors behind the geographical spread and transmission of Zika in the Americas.

BackgroundAn unprecedented Zika virus epidemic occurred in the Americas during 2015-2016. The size of the epidemic in conjunction with newly recognized health risks associated with the virus attracted significant attention across the research community. Our study complements several recent studies which have mapped epidemiological elements of Zika, by introducing a newly proposed methodology to simultaneously estimate the contribution of various risk factors for geographic spread resulting in local transmission and to compute the risk of spread (or re-introductions) between each pair of regions. The focus of our analysis is on the Americas, where the set of regions includes all countries, overseas territories, and the states of the US.Methodology/Principal findingsWe present a novel application of the Generalized Inverse Infection Model (GIIM). The GIIM model uses real observations from the outbreak and seeks to estimate the risk factors driving transmission. The observations are derived from the dates of reported local transmission of Zika virus in each region, the network structure is defined by the passenger air travel movements between all pairs of regions, and the risk factors considered include regional socioeconomic factors, vector habitat suitability, travel volumes, and epidemiological data. The GIIM relies on a multi-agent based optimization method to estimate the parameters, and utilizes a data driven stochastic-dynamic epidemic model for evaluation. As expected, we found that mosquito abundance, incidence rate at the origin region, and human population density are risk factors for Zika virus transmission and spread. Surprisingly, air passenger volume was less impactful, and the most significant factor was (a negative relationship with) the regional gross domestic product (GDP) per capita.Conclusions/SignificanceOur model generates country level exportation and importation risk profiles over the course of the epidemic and provides quantitative estimates for the likelihood of introduced Zika virus resulting in local transmission, between all origin-destination travel pairs in the Americas. Our findings indicate that local vector control, rather than travel restrictions, will be more effective at reducing the risks of Zika virus transmission and establishment. Moreover, the inverse relationship between Zika virus transmission and GDP suggests that Zika cases are more likely to occur in regions where people cannot afford to protect themselves from mosquitoes. The modeling framework is not specific for Zika virus, and could easily be employed for other vector-borne pathogens with sufficient epidemiological and entomological data.

Understanding Child Outcomes within a Multiple Risk Model: Examining Parental Incarceration

The risks in children’s lives often co-occur and overlap in time. The purpose of this study is to examine the impact of parental incarceration within a multiple risk model that allows for the control of other prominent risk factors in a child’s life. The impact of four primary parental risk factors (parental mental illness, parental substance use, parental mental illness, and poverty) on seven child outcomes (school failure, criminal behaviors, being arrested, behavioral difficulties, emotional difficulties, alcohol use, and drug use) was examined. The study utilizes a statistical analysis that is rarely seen in social work research and helps the researcher to better understand the individual contributions of various risk factors. The accumulation of multiple risk factors in a child’s life was found to significantly increase the likelihood that several negative outcomes would occur. The research, however, suggests further that this is an over simplification of the phenomenon and that specific risk factors are more likely to contribute to specific child outcomes.

Risk of Ischemic Heart Disease in Patients With Sjögren’s Syndrome

BackgroundIschemic heart disease (IHD) has emerged as a major cause of morbidity and mortality in patients with autoimmune conditions such as systemic lupus erythematosus and rheumatoid arthritis, but the risk of IHD in Sjögren’s syndrome (SjS) is unknown. To fill this knowledge gap, we estimated the prevalence and risk of IHD with SjS compared to controls from the general population using the Healthcare Cost and Utilization Project National Inpatient Sample 2011 database. Materials and MethodsThe Healthcare Cost and Utilization Project administrative longitudinal database contains encounter-level information on inpatient stays, emergency department visits and ambulatory surgery in all U.S. hospitals. We conducted a cross-sectional study among the inpatient population diagnosed with SjS and matched 1:4 with controls for age, sex and hospital region. Odds ratio for IHD was calculated as cases compared to controls. The contribution of various risk factors to IHD was also evaluated by logistic regression. ResultsAnalysis demonstrated that 7,154 of 13,086 cases (54.7%) of SjS had IHD compared to 27,367 of 52,448 controls (52.2%). The adjusted odds ratio for IHD in those with SjS was 0.898 (95% CI: 0.844-0.955). Patients with SjS were significantly more likely to have hypertension, diabetes, apnea and lipid disorders. ConclusionsTo our knowledge, this is the largest population-based study investigating the risk of IHD in patients with SjS. We found a modest, though statistically significant, decrease in the risk of IHD in SjS compared to controls.

Emotion Ideology Mediates Effects of Risk Factors on Alexithymia Development

Despite its connection to mental and behavioral health complications, elevated alexithymia tends to be associated with low responsiveness and high resistance to psychological intervention. To further understanding of potential treatment targets for clients with alexithymic traits, the present study explored the (a) independent contributions of various risk factors to statistical predictions of alexithymic trait severity, (b) generalizability of risk factor contributions across two culturally distinct samples, and (c) potential for emotion ideology (i.e., beliefs about emotion and emotional experience) to mediate such contributions. Preliminary results suggest emotion socialization and child abuse may be salient contributors to alexithymia severity, whereas effects of trauma exposure may be limited to samples with high overall exposure to alexithymia risk-factors. Moreover, emotion ideology mediates the relation between risk-factor exposure and alexithymia severity. Thus, psychotherapeutic interventions targeting emotion ideology may be beneficial when working with clients with elevated alexithymia.

The role of soft drinks on children obesity: a global analysis using machine learning techniques

BackgroundAmong lifestyle factors, soft drinks’ consumption has been suggested as playing a role in contributing to obesity onset. Aim of present study is to evaluate the contribution of various risk factors to obesity worldwide using a class of machine learning techniques, namely random forests.MethodsData on 2640 children 6–11 years (Argentina, Brazil, France, Georgia, Germany, UK, India, Italy and Mexico) were collected on more than 90 parameters (anthropometrics, built environment, familiar socio economic status, food and activity frequency). Given that sample size is heterogeneous across countries (from 60 up to 1640 children), role played by soft drinks associated with WHO classes of OWO (overweight or Obese) vs. Normal children was estimated using Random Forests (RF), which represent a more robust way to assess the additional contribution of weight status’ predictors compared with traditional statistical methods. RF have been implemented using 150,000 bootstrap samples using Bylander's bias‐correction approach. Incremental role of soft drinks has been evaluated on top of all the other potential predictors. One‐hundred permutations per tree were run for assessing each factor's importance, using Out‐of‐Basket (OOB) classification error rate (CER).ResultsDespite the fact that soft drinks consumption is very different across continents, (children were consuming never 20% Europe, 28% India, 6% South America, and very often 33% Europe, 16% India and 54% South America, p<0.001), its contribution in determining children's weight status was not significant.ConclusionsThe analysis of the association of soft drinks on children obesity is undermined by the great heterogeneity in data. Random forest approach provided stable and informative estimates, showing that the role played by soft drink consumption is not relevant among common recognized determinants of OWO in children.

Risk Factors for First Fractures Among Males With Duchenne or Becker Muscular Dystrophy.

Fractures are a significant concern for individuals with Duchenne/Becker muscular dystrophy with 21% to 44% of males experiencing a fracture. Factors that increase or decrease the risk for fracture have been suggested in past research, although statistical risk has not been determined. In this retrospective cohort study, we used the Muscular Dystrophy Surveillance, Tracking and Research Network cohort, a large, population-based sample to identify risk factors associated with first fractures in patients with Duchenne or Becker muscular dystrophy. Our study cohort included males with Duchenne or Becker muscular dystrophy born between 1982 and 2006 who resided in Arizona, Colorado, Georgia, Iowa, and Western New York, retrospectively identified and followed through 2010. We utilized a multivariate Cox proportional hazard model to determine hazard ratios for relevant factors associated with first fracture risk including race/ethnicity, surveillance site, ambulation status, calcium/vitamin D use and duration, bisphosphonate use and duration, and corticosteroid use and duration. Of 747 cases, 249 had at least 1 fracture (33.3%). Full-time wheelchair use increased the risk of first fracture by 75% for every 3 months of use (hazard ratio=1.75, 95% confidence interval, 1.14, 2.68), but corticosteroid use, bisphosphonate use, and calcium/vitamin D use did not significantly affect risk in the final adjusted model. In this cohort, first fractures were common and full-time wheelchair use, but not corticosteroid use, was identified as a risk factor. The impact of prevention measures should be more thoroughly assessed. Fractures are a significant concern for individuals with dystrophinopathies, but the contribution of various risk factors has not been consistently demonstrated.

Low Socioeconomic Status Is an Independent Risk Factor for Ischemic Stroke: A Case-Control Study in North Indian Population

Background: Stroke is a multifactorial disease and is influenced by complex environmental interactions. The contribution of various risk factors to the burden of stroke worldwide is not well known, particularly in developing countries. The present case-control study is aimed at exploring the association between a low socioeconomic status and the risk of ischemic stroke among the North Indian population. Methods: The study design was a hospital-based, case-control study. Age- and sex-matched controls were included. The demographic characteristics and risk factor variables were documented by means of a personal interview through a standardized case record form. The household asset index for determining the socioeconomic status (HAISS) was used for the assessment of the socioeconomic status of the population. HAISS was validated with the widely used Kuppuswamy scale for measurement of socioeconomic status. The multivariable logistic regression model was used to estimate the odds ratio associated with stroke. Results: In all, 224 ischemic stroke patients and 224 controls were recruited between February 2009 and February 2012. The mean age of cases and controls was 53.47 ± 14 and 52.92 ± 13.4, respectively. The low economic status was independently associated with the risk of ischemic stroke after adjustment for demographic and risk factor variables (OR 2.8; 95% CI 1.2-6.3). Conclusion: Our findings suggest that there is a significant association between a low socioeconomic status and the risk of ischemic stroke risk in North Indian population. Well-designed studies embedded with long-term prospective cohorts are required for confirming the results.

Risk factors for established vertebral fractures in Japanese patients with rheumatoid arthritis: Results from a large prospective observational cohort study

Objective. The aim of this study was to evaluate the associations between potential risk factors and the occurrence of established vertebral fractures in Japanese patients with rheumatoid arthritis (RA).Methods. A total of 10,469 patients with RA were enrolled in a prospective, observational study from 2000 to 2011. Self-reported vertebral fractures were verified using patient's medical records and radiographs. Cox proportional hazards models were used to analyze independent contributions of various risk factors for established vertebral fracture occurrence.Results. During a mean follow-up of 5.8 years, established vertebral fractures in 170 patients were verified with medical records and radiographs. Multivariate Cox regression analyses estimated that the hazards ratios of sustaining vertebral fractures increased by 1.84 for female gender, 1.72 for every 10 years of increased age, 1.26 for Disease Activity Score in 28 joints (DAS28), 1.44 for Japanese Health Assessment Questionnaire-Disability Index (J-HAQ-DI), 2.21 for history of any previous fractures, and 1.09 for daily prednisolone dose (mg/day).Conclusion. We confirmed the associations between vertebral fractures and advanced age, J-HAQ-DI, and high daily prednisolone dose; and found significant correlations between vertebral fractures and female gender, DAS28, and history of any previous fracture in Japanese RA patients.

SAT0485 Risk Factors for Proximal Humerus Fracture in Japanese Patients with Rheumatoid Arthritis: A Prospective Observational Cohort Study

BackgroundPatients with rheumatoid arthritis (RA) have a higher risk of fractures at all skeletal sites than individuals without RA. Our observational cohort RA study in Japan (conducted by the Institute...

Prevalence of chronic kidney disease across levels of glycemia among adults in Pudong New Area, Shanghai, China

BackgroundFew population-based studies have examined the relationship between glycemic status and chronic kidney disease (CKD) in China. We examined the prevalence of CKD across categories of glycemia [diagnosed diabetes, undiagnosed diabetes (fasting plasma glucose [FPG] ≥ 126 mg/dL), prediabetes (FPG 100–126 mg/dL) and normal glycemia (FPG <100 mg/dL)] among Chinese adults and assessed the relative contribution of dysglycemia (prediabetes and/or diabetes) to the burden of CKD.Methods5,584 Chinese adults aged 20–79 years were selected from the Pudong New Area of Shanghai through a multistage random sampling. Demographic and lifestyle characteristics, anthropometry and blood pressure were measured. Biochemical assays included FPG, serum creatinine and lipids, urinary creatinine and albumin. Prevalence of albuminuria [urine albumin-to-creatinine ratio (ACR) ≥ 30 mg/g], decreased kidney function and CKD (either decreased kidney function or albuminuria) across levels of glycemia were estimated.ResultsThe prevalence of albuminuria, decreased kidney function and CKD each increased with higher glycemic levels (P < 0.001). Based on the MDRD Study equation, the unadjusted CKD prevalence was 30.9%, 28.5%, 14.1% and 9.2% in those with diagnosed diabetes, undiagnosed diabetes, prediabetes and normoglycemia, respectively. The corresponding age-, gender- and hypertension-adjusted CKD prevalence were 25.8%, 25.0%, 12.3% and 9.1%, respectively. In a multivariable analysis, the factors associated with CKD were hypertension (Odds ratio [OR] 1.70, 95% confidence interval [CI]: 1.42-2.03), dysglycemia (OR 1.65, 95% CI: 1.39-1.95), female gender (OR 1.48, 95% CI: 1.25-1.75), higher triglycerides (OR 1.14, 95% CI: 1.08-1.20 per mmol/L), higher body mass index (OR 1.08, 95% CI: 1.05-1.10 per kg/m2), and older age (OR 1.02, 95% CI: 1.01 -1.03 per year). The population attributable risks (PARs) associated with diabetes, prediabetes, dysglycemia (diabetes and prediabetes) and hypertension were 18.4%, 19.7%, 30.3% and 44.5% for CKD as defined by the MDRD study equation, and 15.8%, 24.4%, 29.2% and 10.0% with the CKD-EPI equation. Estimates of prevalence and ORs of the relative contribution of various risk factors to CKD obtained with the CKD-EPI equation were similar.ConclusionsAs much as 30% of the CKD burden may be associated with dysglycemia among Chinese adults, independent of age, gender and hypertension status. Prevention and control of diabetes and prediabetes should be a high priority in reducing the CKD burden in China.

Risk factors associated with the occurrence of distal radius fractures in Japanese patients with rheumatoid arthritis: a prospective observational cohort study

The aims of this study were to evaluate the association between potential risk factors and the occurrence of distal radius fractures in Japanese patients with rheumatoid arthritis (RA). A total of 9,987 patients (82.0% female; mean age, 55.7years) with RA were enrolled in a prospective, observational study from 2000 to 2011. Self-reported distal radius fractures were verified using patient medical records. Cox proportional hazards models were used to analyze independent contributions of various risk factors to distal radius fracture occurrence. During a mean follow-up of 5.7years, 139 patients reported 153 distal radius fractures. Among these patients, 85 distal radius fractures following minor trauma in 85 patients (6 men, 79 women) were verified with medical records. Female gender (hazard ratio [HR], 2.96; 95% confidence interval [CI], 1.18-7.45; P = 0.021), age (per 10years, HR 1.55; 95% CI, 1.24-1.95, P = 0.00016), body mass index (BMI) (per 1kg/m(2), HR, 1.11; 95% CI, 1.03-1.19; P = 0.0034), daily prednisolone dose (per milligram per day, HR, 1.10; 95% CI, 1.05-1.16; P = 0.00015), and physician global visual analog scale (0-10cm, HR, 0.98; 95% CI, 0.96-1.00; P = 0.034) were significantly associated with the occurrence of distal radius fractures in Japanese patients with RA. A reduction in the daily prednisolone dose, together with the prevention of falls in female patients of advanced age with RA and a high BMI may be important in preventing distal radius fractures.

Risk factors for epilepsy in Nigerians - a cross-sectional case-control study

The identification of risk factors that predispose to development of epilepsy is crucial to its primary prevention. This study evaluated the risks conferred by some predisposing factors. This cross-sectional analytical study assessed the relative contributions of various risk factors to development of epilepsy in 244 adult Nigerians with epilepsy compared with equal number of age- and sex-matched controls. Odds ratio and Fisher exact test were used to express significant association. Birth asphyxia (OR 6.87), recurrent childhood febrile convulsions (OR 5.74), central nervous system (CNS) infections (OR 3.38), head trauma (OR 1.82), rural dwelling without health care access (OR 2.44), and history of epilepsy in first-degree relatives (OR 3.44) were identified as significant risk factors for epilepsy. Prompt diagnosis and appropriate treatment for febrile diseases and CNS infections, use of head helmets and car seat belts would contribute to reduced incidence.

Premature coronary heart disease in systemic lupus erythematosus: what risk factors do we understand?

Coronary heart disease (CHD) is a major cause of mortality in systemic lupus erythematosus (SLE). This 'accelerated atherosclerosis' is due to a combination of traditional risk factors such as hypertension and hyperlipidemia, and also disease-related factors such as chronic inflammation. Recent work has provided valuable insights into the relative contribution of various risk factors and also identified novel risk factors. An understanding of risk factors is fundamental to the prevention of CHD in SLE. In this review, we will discuss the role of risk factors for CHD in SLE and offer some strategies for their assessment and management.

Elaborations on Sexual Assault on Dates Among Israeli Students

The current study of 668 Israeli male and female students examines the prevalence of gendered risk factors for sexual assault (SA) on dates, posttraumatic stress disorder (PTSD) as a detrimental effect of SA, and self-efficacy as resiliency to refuse unwanted sex following SA. Two different sets of risk factors that increased the likelihood of SA on dates emerged from the hierarchical regression. Sexual experience, use of drugs, and private location increased the risk of being SA victims among males, whereas sexual experience, perceived provocative behavior, and alcohol use increased the risk among females. In addition, PTSD and self-efficacy to refuse unwanted sex following SA on dates were predicted by the extent of coercive sexual victimization. PTSD was also predicted by subjective perception of sexual behavior and rape myths, whereas efficacy was predicted by private location. The findings contribute to the literature by showing the contribution of various risk factors to experiencing SA, and by showing SA effect on PTSD and self-efficacy.

SAT0347 Risk factors associated with incident hip fractures in 9,720 japanese patients with rheumatoid arthritis: A prospective observational cohort study

BackgroundPatients with rheumatoid arthritis (RA) have a high risk of hip fracture. Limited data exist in the literature concerning risk factors for incident hip fractures in patients with RA. Previously,we...

Risk factors associated with the occurrence of hip fracture in Japanese patients with rheumatoid arthritis: a prospective observational cohort study

Risk factors associated with the occurrence of hip fracture in Japanese patients with rheumatoid arthritis (RA) were evaluated in a prospective, observational cohort study. Physical disability, advanced age, history of total knee replacement (TKR), and low body mass index (BMI) appear to be associated with the occurrence of hip fracture. This study seeks to evaluate the association between potential risk factors and the occurrence of hip fractures in Japanese RA patients. A total of 9,720 patients (82.1% female; mean age, 55.7 years) with RA were enrolled in a prospective observational study from 2000 to 2010. Self-reported hip fractures were verified using patient medical records. Cox proportional hazards models were used to analyze independent contributions of various risk factors to hip fracture occurrence. During a mean follow-up of 5.2 years, 152 patients reported 152 hip fractures. Among these patients, 97 hip fractures in 97 patients (15 males, 82 females) were verified with medical records. Japanese version of the Health Assessment Questionnaire (J-HAQ) disability score [per 1 score, hazard ratio (HR), 2.64; 95% confidence interval (CI), 1.94-3.58], age (per 10 years; HR, 1.53; 95% CI, 1.25-1.87), history of TKR (HR, 3.75; 95% CI, 1.57-8.96), and BMI (per 1 kg/m2, HR, 0.92; 95% CI, 0.86-0.99) were significantly associated with hip fractures. Among the scores on the eight domains of the J-HAQ, J-HAQ (arising) (HR, 1.74; 95% CI, 1.28-2.36) and J-HAQ (hygiene) (HR, 1.58; 95% CI, 1.11-2.24) were significantly correlated with the occurrence of hip fracture. High J-HAQ disability score, advanced age, history of TKR, and low BMI appear to be associated with the occurrence of hip fractures in Japanese RA patients. Among the eight domains of the J-HAQ, arising and hygiene disabilities appear to be correlated with the occurrence of hip fractures in this patient population.

Incidence of retinopathy of prematurity and risk factors in the South-Western Region of Iran

Aims:The aim of this study was to report the incidence of retinopathy of prematurity (ROP) and the contribution of various risk factors to ROP in the south-western region of Iran.Material and Methods:This cross-sectional case-control series reviewed all low birth weight (LBW, ≤2000 g) neonates and/or neonates less than 32 weeks gestational age who had been hospitalized in the Neonatal Intensive Care Unit from 2006 to 2010. The cohort was divided into infants without ROP (nonROP group) and infants with ROP (ROP group). Infants were first examined by a group of pediatric ophthalmologists 6 weeks after delivery, and then were followed every 1-2 weeks until death, discharge or complete retinal avascularization. If an infant developed ROP, further examinations were performed based on the Early Treatment for Retinopathy of Prematurity Study protocol. Demographic data, medical treatment, and ophthalmic disorders were all statistically analyzed.Results:A total of 576 infants met the criteria for evaluation. Of 576 total patients, 183 infants (32%) (88 males, 95 females) had ROP. There were significant differences between groups in gestational age, body weight, and duration of oxygen administration, and sepsis (P<0.05). Male/female ratio, single and multiple births, and jaundice, phototherapy, and blood transfusion were not significant. The majority of ROP was stage I or II (137, 74.8%). Stage III or greater developed in 46 infants (25.1%) [Note: The ocular history and ocular outcomes are not risk factors.]Conclusions:The incidence of ROP in this study is higher than that in other parts of the world. Awareness and knowledge of ROP and its relative risks need to be reinforced in ophthalmologists and other health practitioners.

Stroke Update: Risk Factors and Primary Prevention of Stroke

Received: March 23, 2012 / Revised: March 26, 2012 Accepted: March 28, 2012 Address for correspondence: Soo Joo Lee, MD, PhD Department of Neurology, Eulji University Hospital, Eulji University School of Medicine, 95 Dusanseo-ro, Seo-gu, Daejeon 302-779, Korea Tel: +82-42-611-3430, Fax: +82-42-611-3858 E-mail: sjoolee@eulji.ac.kr The aim of this article is to review the results of recent researches with regard to risk factors or primary prevention of stroke. We have discussed the contribution of various risk factors to the burden of stroke, variability in blood pressure, intensive glycemic control, lipid management, management of asymptomatic carotid stenosis, vitamin B supplements lowing homocysteine, lifestyle factors, and aspirin effi cacy for primary prevention of stroke. (Korean J Stroke 2012;14:12-18)

Risk factors for ischaemic and intracerebral haemorrhagic stroke in 22 countries (the INTERSTROKE study): a case-control study

The contribution of various risk factors to the burden of stroke worldwide is unknown, particularly in countries of low and middle income. We aimed to establish the association of known and emerging risk factors with stroke and its primary subtypes, assess the contribution of these risk factors to the burden of stroke, and explore the differences between risk factors for stroke and myocardial infarction. We undertook a standardised case-control study in 22 countries worldwide between March 1, 2007, and April 23, 2010. Cases were patients with acute first stroke (within 5 days of symptoms onset and 72 h of hospital admission). Controls had no history of stroke, and were matched with cases for age and sex. All participants completed a structured questionnaire and a physical examination, and most provided blood and urine samples. We calculated odds ratios (ORs) and population-attributable risks (PARs) for the association of all stroke, ischaemic stroke, and intracerebral haemorrhagic stroke with selected risk factors. In the first 3000 cases (n=2337, 78%, with ischaemic stroke; n=663, 22%, with intracerebral haemorrhagic stroke) and 3000 controls, significant risk factors for all stroke were: history of hypertension (OR 2.64, 99% CI 2.26-3.08; PAR 34.6%, 99% CI 30.4-39.1); current smoking (2.09, 1.75-2.51; 18.9%, 15.3-23.1); waist-to-hip ratio (1.65, 1.36-1.99 for highest vs lowest tertile; 26.5%, 18.8-36.0); diet risk score (1.35, 1.11-1.64 for highest vs lowest tertile; 18.8%, 11.2-29.7); regular physical activity (0.69, 0.53-0.90; 28.5%, 14.5-48.5); diabetes mellitus (1.36, 1.10-1.68; 5.0%, 2.6-9.5); alcohol intake (1.51, 1.18-1.92 for more than 30 drinks per month or binge drinking; 3.8%, 0.9-14.4); psychosocial stress (1.30, 1.06-1.60; 4.6%, 2.1-9.6) and depression (1.35, 1.10-1.66; 5.2%, 2.7-9.8); cardiac causes (2.38, 1.77-3.20; 6.7%, 4.8-9.1); and ratio of apolipoproteins B to A1 (1.89, 1.49-2.40 for highest vs lowest tertile; 24.9%, 15.7-37.1). Collectively, these risk factors accounted for 88.1% (99% CI 82.3-92.2) of the PAR for all stroke. When an alternate definition of hypertension was used (history of hypertension or blood pressure >160/90 mm Hg), the combined PAR was 90.3% (85.3-93.7) for all stroke. These risk factors were all significant for ischaemic stroke, whereas hypertension, smoking, waist-to-hip ratio, diet, and alcohol intake were significant risk factors for intracerebral haemorrhagic stroke. Our findings suggest that ten risk factors are associated with 90% of the risk of stroke. Targeted interventions that reduce blood pressure and smoking, and promote physical activity and a healthy diet, could substantially reduce the burden of stroke. Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Canadian Stroke Network, Pfizer Cardiovascular Award, Merck, AstraZeneca, and Boehringer Ingelheim.