Association between physical activity levels and stroke incidence in middle-aged and older populations: a cross-sectional and Mendelian randomisation study.

The amount and intensity of physical activity required to prevent stroke are yet to be fully determined because of previous reliance on self-reporting measures. Furthermore, the association between objectively measured time spent being sedentary as an independent risk factor for stroke is unknown. To investigate the associations of accelerometer-measured sedentary time and physical activity of varying intensity and duration with the risk of incident stroke. This cohort study involved participants who were enrolled in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study from February 5, 2003, to October 30, 2007. Accelerometer data were collected from 7607 Black and White adults 45 years or older in the contiguous US between May 12, 2009, and January 5, 2013. Data on other races and ethnicities were not collected for scientific and clinical reasons. By design, Black adults and residents of the southeastern US stroke belt and stroke buckle were oversampled. Data were analyzed from May 5, 2020, to November 11, 2021. Sedentary time, light-intensity physical activity (LIPA), and moderate- to vigorous-intensity physical activity (MVPA) were measured using a hip-mounted accelerometer worn for 7 consecutive days and stratified by tertile for the analyses. Incident stroke. Among 7607 participants, the mean (SD) age was 63.4 (8.5) years; 4145 participants (54.5%) were female, 2407 (31.6%) were Black, and 5200 (68.4%) were White. A total of 2523 participants (33.2%) resided in the stroke belt, and 1638 (21.5%) resided in the stroke buckle. Over a mean (SD) of 7.4 (2.5) years of follow-up, 286 incident stroke cases (244 ischemic [85.3%]) occurred. The fully adjusted hazard ratios (HRs) for incident stroke in the highest tertile compared with the lowest tertile were 0.74 (95% CI, 0.53-1.04; P = .08) for LIPA and 0.57 (95% CI, 0.38-0.84; P = .004) for MVPA. Higher sedentary time was associated with a 44% greater risk of incident stroke (HR, 1.44; 95% CI, 0.99-2.07; P = .04). When comparing the highest with the lowest tertile, mean sedentary bout duration was associated with a significantly greater risk of incident stroke (HR, 1.53; 95% CI, 1.10-2.12; P = .008). After adjustment for sedentary time, the highest tertile of unbouted MVPA (shorter bouts [1-9 minutes]) was associated with a significantly lower risk of incident stroke compared with the lowest tertile (HR, 0.62; 95% CI, 0.41-0.94; P = .02); however, bouted MVPA (longer bouts [at least 10 minutes]) was not (HR, 0.78; 95% CI, 0.53-1.15; P = .17). When expressed as continuous variables, sedentary time was positively associated with incident stroke risk (HR per 1-hour/day increase in sedentary time: 1.14; 95% CI, 1.02-1.28; P = .02), and LIPA was negatively associated with incident stroke risk (HR per 1-hour/day increase in LIPA: 0.86; 95% CI, 0.77-0.97; P = .02). In this cohort study, objectively measured LIPA, MVPA, and sedentary time were significantly and independently associated with incident stroke risk. Longer sedentary bout duration was also independently associated with an increased risk of incident stroke. These findings suggest that replacing sedentary time with LIPA, or even very short bouts of MVPA, may lower stroke risk, supporting the concept of moving more and sitting less as a beneficial stroke risk reduction strategy among adults.

Few studies have examined the association between multivitamin use and the risk of stroke incidence and mortality, and the results remain inconclusive as to whether multivitamins are beneficial. The associations between multivitamin use and the risk of incident stroke and stroke mortality were prospectively examined in 86142 women in the Nurses' Health Study, aged 34-59years and free of diagnosed cardiovascular disease at baseline. Multivitamin use and covariates were updated every 2years and strokes were documented by review of medical records. Hazard ratios of total, ischaemic and hemorrhagic strokes were calculated across categories of multivitamin use (non-user, past, current user) and duration (years), using Cox proportional hazards models. During 32years of follow-up from 1980 to 2012, 3615 incident strokes were documented, including 758 deaths from stroke. In multivariate analyses, women who were current multivitamin users did not have a lower risk of incident total stroke compared to non-users [relative risk (RR) 1.02, 95% confidence interval (CI) 0.93-1.11], even those with longer durations of 15 or more years of use (RR 1.08, 95% CI 0.97-1.20) or those with a lower quality diet (RR 0.96, 95% CI 0.80-1.15). There was also no indication of benefit from multivitamin use for incident ischaemic or hemorrhagic strokes or for total stroke mortality. Long-term multivitamin use was not associated with reduced risk of stroke incidence or mortality amongst women in the study population, even amongst those with a lower diet quality. An effect in a less well-nourished population cannot be ruled out.

Smog and risk of overall and type-specific cardiovascular diseases: A pooled analysis of 53 cohort studies with 21.09 million participants

To investigate the association of change in leisure-time physical activity (LTPA) occurring during the postretirement period with incident stroke. The current study enrolled 12,644 retired workers from the Dongfeng-Tongji cohort from April to October 2013. The change in LTPA was categorized as follows, according to whether the LTPA time met the WHO recommended minimum (at least 150 minutes per week): (1) stayed inactive at both surveys; (2) stayed inactive at the 2008 survey but became active at the 2013 survey; (3) stayed active at the 2008 survey but became inactive at the 2013 survey; (4) stayed active at both surveys. We used multivariable-adjusted Cox proportional hazards regression models to examine the association between change in LTPA and the risk of incident stroke. During 70,437 person-years of follow-up, we documented 549 incident stroke cases, including 434 incident ischemic stroke cases and 115 incident hemorrhagic stroke (HS) cases. Compared with participants who stayed active at both the 2008 and 2013 surveys, those who were active at the 2008 survey but became inactive at the 2013 survey had significantly higher risks of incident total stroke (hazard ratio [HR] 1.30, 95% CI 1.03, 1.65) and HS (HR 2.34, 95% CI 1.51, 3.63). When stratified by body mass index (BMI) categories, a significant elevated risk of total stroke was seen among overweight participants who stayed active at the 2008 survey but became inactive at the 2013 survey (HR 1.65, 95% CI 1.20, 2.27). The risk of incident stroke decreased with increasing LTPA levels between the 2 surveys (HR of per 150 min/wk increase of LTPA: HR 0.97, 95% CI 0.94, 1.00). In addition, we found that compared with participants who maintained their BMI and stayed active at both the 2008 and 2013 surveys, those who were inactive at both points or who became inactive had higher risks of stroke (HR 2.13, 95% CI 1.09, 4.15; HR 1.50, 95% CI 1.07, 2.08, respectively). Among Chinese older adults, increasing LTPA levels during the postretirement period was associated with a lower risk of incident stroke. Retired individuals should be encouraged to participate in LTPA more frequently to lessen future risk of incident stroke.

Whether physical activity reduces stroke risk remains controversial. We used a meta-analysis to examine the overall association between physical activity or cardiorespiratory fitness and stroke incidence or mortality. We searched MEDLINE from 1966 to 2002 and identified 23 studies (18 cohort and 5 case-control) that met inclusion criteria. We estimated the overall relative risk (RR) of stroke incidence or mortality for highly and moderately active individuals versus individuals with low levels of activity using the general variance-based method. The meta-analysis documented that there was a reduction in stroke risk for active or fit individuals compared with inactive or unfit persons in cohort, case-control, and both study types combined. For cohort studies, highly active individuals had a 25% lower risk of stroke incidence or mortality (RR=0.75; 95% CI, 0.69 to 0.82) compared with low-active individuals. For case-control studies, highly active individuals had a 64% lower risk of stroke incidence (RR=0.36; 95% CI, 0.25 to 0.52) than their low-active counterparts. When we combined both the cohort and case-control studies, highly active individuals had a 27% lower risk of stroke incidence or mortality (RR=0.73; 95% CI, 0.67 to 0.79) than did low-active individuals. We observed similar results in moderately active individuals compared with inactive persons (RRs were 0.83 for cohort, 0.52 for case-control, and 0.80 for both combined). Furthermore, moderately and highly active individuals had lower risk of both ischemic and hemorrhagic strokes than low-active individuals. We conclude that moderate and high levels of physical activity are associated with reduced risk of total, ischemic, and hemorrhagic strokes.

Stroke is a major public health concern and a leading cause of disability and death in aging populations. Intrinsic capacity (IC), a concept introduced by the World Health Organization, reflects anindividual'soverall functional ability across multiple domains including cognition, psychological well-being, mobility, vitality, and sensory function. IC has emerged as a core metric within the healthy aging framework, but its prospective relationship with stroke risk remains unclear. A deeper understanding of this link may inform early, function-based prevention strategies. This study used data from 10,751 participants aged 45 years or older from the China Health and Retirement Longitudinal Study (CHARLS). Cox proportional hazards models were used to estimate the association between IC and incident stroke, with stepwise adjustment for demographic, behavioral, and health-related covariates. Modeling IC as a continuous variable enabled examination of linear trends, while quartile-based classification allowed evaluation of potential non-linear associations and improved interpretability. Kaplan-Meier curves and log-rank tests were used to compare stroke-free survival across IC quartiles. Restricted cubic spline analysis was performed to explore the presence of a non-linear association between IC and stroke risk. Robustness was tested through sensitivity analyses excluding participants with baseline cognitive impairment and those aged ≥80 years. Statistical analyses were conducted using Stata and R. Over a 7-year follow-up, 243 participants (2.26%) experienced incident stroke. Stroke incidence decreased progressively with increasing IC levels, from 4.84% in the lowest quartile to 0.46% in the highest. Kaplan-Meier analysis showed significantly lower cumulative stroke incidence among individuals with higher IC (log-rank p < 0.001). In fully adjusted Cox models, each one-point increase in IC was associated with a 35.1% reduction in stroke risk (HR = 0.649; 95% CI: 0.599-0.702). Compared to the lowest IC quartile, the highest quartile had an 89.6% lower stroke risk (HR = 0.104; 95% CI: 0.055-0.197). Restricted cubic spline models confirmed a predominantly linear inverse association, with a steeper risk gradient at lower IC levels. Subgroup analyses revealed stronger protective associations in women, older adults (≥60 years), urban residents, and non-smokers or non-drinkers. Results remained consistent across all sensitivity analyses. Higher IC was independently associated with a significantly reduced risk of incident stroke, underscoring IC's potential as a holistic, function-based indicator of cerebrovascular vulnerability. These findings provide empirical support for the World HealthOrganization'shealthy aging framework, emphasizing IC as a modifiable reserve that reflects early, multidomain functional decline before clinical disease onset. Incorporating IC into routine screening and prevention strategies may enhance early identification of high-risk individuals and enable more targeted, function-oriented interventions, thereby promoting healthy aging and helping to reduce the future burden of stroke.

Evidence is limited on the impact of childhood socioeconomic status, adulthood socioeconomic status and chronic conditions on risk of incident stroke in later life. We aimed to examine these associations using data from a nationally representative sample of the Health and Retirement Study. Stroke-free participants (n = 22,847) aged > 50 years in the Health and Retirement Study (1992-2008) were analyzed. Childhood and adulthood socioeconomic status were assessed using parental and participant's education attainments. Incident stroke was defined as self-reported first incident stroke. Of the study sample, 2298 subjects experienced first incident stroke (10.06%). Cox's regression models indicate that subjects with low childhood socioeconomic status had 1.36 times higher risk (95% confidence interval: 1.18-1.57) of first incident stroke than those with high childhood socioeconomic status. There was an 8% reduction of this association after adjustment for adulthood socioeconomic status. Adults with diabetes mellitus had the highest hazard ratio (1.91, 95% confidence interval: 1.63-2.23) for incident stroke, followed by heart disease (1.69, 1.48-1.93), and then hypertension (1.56, 1.40-1.75). Significant interaction effect of childhood socioeconomic status and diabetes mellitus, and combined effects of socioeconomic status and chronic conditions on risk of incident stroke were observed. Both low socioeconomic status in childhood and adulthood socioeconomic status predict the risk of stroke. There are significantly combined effects of socioeconomic status and chronic conditions on the risk of stroke. Improving socioeconomic status across the life span and aggressive control of chronic conditions may play pivotal roles in the prevention of stroke development.

Reduced lung function has been shown to be a significant predictor of non-fatal ischaemic heart disease, and of mortality due to cardiovascular disease. Fewer studies have analysed the relationship between lung function and risk of fatal or non-fatal stroke. The present study presents results on the relation between forced expiratory volume in one second (FEV1) and risk of incident and fatal first-ever stroke. The analyses are based on prospective cohort data from 12 878 eligible men and women aged 45-84 years, who participated in the first health examination of the Copenhagen City Heart Study in 1976-1978. The subjects were followed from day of entry until 31 December 1993. During that period 808 first-ever strokes occurred of which 153 were fatal within 28 days. Risk of incident and fatal stroke was estimated by means of Cox hazard regression. The analyses included adjustment for potential confounders: sex, age, smoking, inhalation, body mass index, systolic blood pressure, triglycerides, physical activity in leisure time, education, diabetes mellitus, and antihypertensive treatment. We found an inverse association between FEV1 and risk of first-time stroke. For each 10% decrease in FEV1 in percentage of expected, the relative risk (RR) increased 1.05 (95% CI : 1.00-1.09, P = 0.03). This represents an approximately 30% higher risk of stroke in the group of people with the lowest lung function as compared to the group with the highest lung function. The association between lung function and risk of fatal stroke resembled that of risk of incident stroke (fatal and non-fatal). The RR was 1.11 (95% CI : 1.03-1.19) for each 10% decrease in FEV1 in percentage of expected. This represents approximately a doubling of the risk between the highest and lowest lung function groups. This study shows that reduced lung function measured in percentage of predicted FEV1 is a predictor of first-time stroke and fatal stroke independent of smoking and inhalation. The high risk of fatal first-ever stroke in the group of people with low lung function may be of significance in both the design and interpretation of clinical trials.

Cumulative evidence suggests a correlation between physical or mental activity and the risk of stroke. However, the combined impact of these activities on stroke onset remains unexplored. This study identified physical and mental activity patterns using principal component analysis and investigated their associations with risk of incident stroke in the general population. Our study was sourced from the UK Biobank cohort between 2006 and 2010. Information on physical and mental-related activities were obtained through a touch-screen questionnaire. The incident stroke was diagnosed by physicians and subsequently verified through linkage to Hospital Episode Statistics. Principal component analysis was used to identify potential physical and mental activity patterns. Cox proportional hazard regression models were performed to calculate hazard ratios (HRs) and 95% CIs of incident stroke, adjusting for potential confounders. The initial UK Biobank cohort originally consisted of 502 411 individuals, of whom a total of 386 902 participants (aged 38-79 years) without any history of stroke at baseline were included in our study. During a median follow-up of 7.7 years, 6983 (1.8%) cases of stroke were documented. The mean age of the included participants was 55.9 years, and the proportion of women was 55.1%. We found that multiple individual items related to physical and mental activity showed significant associations with risk of stroke. We identified 4 patterns of physical activity and 3 patterns of mental activity using principal component analysis. The adherence to activity patterns of vigorous exercise, housework, and walking predominant patterns were associated with a lower risk of stroke by 17% (HR, 0.83 [95% CI, 0.78-0.89]; 20% (HR, 0.80 [95% CI, 0.75-0.85]; and 20% (HR, 0.80 [95% CI, 0.75-0.86), respectively. Additionally, the transportation predominant pattern (HR, 1.36 [95% CI, 1.28-1.45) and watching TV pattern (HR, 1.43 [95% CI, 1.33-1.53) were found to be significantly associated with a higher risk of stroke. These associations remained consistent across all subtypes of stroke. Activity patterns mainly related to frequent vigorous exercise, housework, and walking were associated with lower risks of stroke and all its subtypes. Our findings provide new insights for promoting suitable patterns of physical and mental activity for primary prevention of stroke.

The triglyceride-glucose (TyG) index, a reliable surrogate marker of insulin resistance, has been shown as an independent risk factor for stroke. Still, the interaction between metabolic syndrome (MetS) and the TyG index in determining stroke risk remains to be clarified, which may help optimize stroke prevention strategies. This study aims to explore whether metabolic syndrome (MetS) influences the association between the TyG index and the risk of stroke. A total of 7770 middle-aged and older participants free of stroke at baseline were enrolled from the China Health and Retirement Longitudinal Study. The TyG index was calculated as ln (triglyceride [mg/dL] × fasting glucose [mg/dL]/2). MetS was defined following the modified International Diabetes Federation criteria. The outcome was self-reported, physician-diagnosed, incident stroke during follow-up. Cox proportional hazard models were used to examine whether MetS influences the associations between the TyG index and the risk of incident stroke. A total of 568 (7.3%) incident stroke cases occurred after a median observation time of 7.0 years. After adjusting for potential confounders, a higher TyG level was associated with an increased risk of incident stroke (hazard ratio (HR) 1.19, 95% CI 1.05-1.33, P = 0.016). The association was significant in participants without MetS (HR 1.69, 95% CI 1.40-1.97, P < 0.001), but not in those with MetS (HR 1.05, 95% CI 0.88-1.21, P = 0.599). The interaction between the TyG index and MetS on the risk of incident stroke was significant (P = 0.004). MetS influenced the association of the TyG index with the risk of incident stroke among middle-aged and older Chinese adults. The TyG index may be more effective for stroke risk stratification in populations without MetS compared to those with MetS.

Hyperuricemia and risk of stroke: A systematic review and meta-analysis of prospective studies

Background and purposeThe relationship between sleep duration and stroke are inconclusive in China, especially in those individuals with metabolic syndrome. We aimed to investigate the association between sleep duration and incident stroke in participants with metabolic syndrome or its specific components in China.Materials and methodsData were taken from the 2011 and 2015 waves of China Health and Retirement Longitudinal Study (CHARLS). Habitual sleep duration (≤6, 6∼8 [reference], >8 h), daytime napping (0, 1∼60 [reference], and >60 min) were determined by self-reported questionnaires. Metabolic syndrome was defined by blood assessment and biomarkers combined with self-reported doctors’ diagnosis. Incident stroke was determined by reported stroke from 2011 to 2015 wave. Cross-sectional and longitudinal associations between sleep and (incident) stroke at baseline and 4-year follow-up period were tested among the population with metabolic syndrome and its components.ResultsA U-shaped relationship was observed between sleep duration and stroke in cross-sectional analysis. Sleep ≤ 6 h/night had a greater risk of incident stroke (hazard ratio [HR] 1.65; 95% confidence interval [CI] 1.04–2.61) compared with sleep 6∼8 h/night. And the HR of stroke was 1.62 (95%CI, 1.03–2.53) for sleep < 7 h/day compared to 7∼9 h/day. These associations were more evident in the female and individuals aged 45–65 years. Furthermore, the effect of short sleep duration on incident stroke was different in each component of metabolic syndrome, which was more pronounced in participants with elevated blood pressure. And a significant joint effect of sleeping ≤ 6 h/night and no napping on risk of stroke was observed (HR 1.82, 95%CI 1.06–3.12).ConclusionShort sleep duration was an independent risk factor for incident stroke, especially among females, individuals aged 45–65 years, or those with some components of metabolic syndrome, such as hypertension. Napping could buffer the risk of short sleep duration on incident stroke.

BackgroundImpaired pulmonary function and physical inactivity are established risk factors for cerebrovascular disease, yet their combined contribution to stroke risk has not been systematically evaluated across diverse populations. This study aimed to evaluate the joint association of peak expiratory flow (PEF) and physical activity (PA) with incident stroke risk in US and Chinese adults.MethodsThis prospective cohort study enrolled 10,620 stroke-free participants aged 50 years or older from the Health and Retirement Study (HRS, n = 6,700) and the China Health and Retirement Longitudinal Study (CHARLS, n = 3,920). Participants were categorized into four groups based on cohort-specific median PEF and self-reported PA. Multivariable Cox proportional hazards models estimated hazard ratio (HR) for incident stroke over a 7-year median follow-up.ResultsAmong HRS participants (n = 6,700, mean age 66.0 ± 10.3 years) and CHARLS participants (n = 3,920, mean age 61.5 ± 7.8 years), 590 incident strokes were recorded. Compared to the low PEF/inactive group, those with both high PEF and regular PA exhibited the lowest stroke risk in both cohorts (HRS: HR, 0.56 [95% CI, 0.38–0.82]; CHARLS: HR, 0.62 [95% CI, 0.44–0.89]). Participants with only one favorable factor showed attenuated and inconsistent risk reductions. No significant interactions were found by age, sex, or comorbidities (all P for interaction > 0.05).ConclusionsPreserved pulmonary function combined with regular physical activity is associated with a significantly lower stroke risk across diverse populations. Integrated assessment of these factors may improve stroke risk stratification and inform targeted prevention strategies.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-026-27212-8.

The relationship between hyperuricemia (HUA) and stroke remains controversial. In this systematic review, we discuss the association between HUA and stroke. The PubMed, Embase, Web of Science, and Cochrane Library were searched from their earliest records to March 13th, 2024, and additional papers were identified through a manual search. Prospective studies that provided a multivariate-adjusted estimate of the association between HUA and risk of stroke incidence and mortality, represented as relative risks (RRs) with 95% confidence intervals (CIs), were eligible. A total of 22 studies including 770,532 adults were eligible and included. Hyperuricemia was associated with a significantly increasing risk of both stroke incidence (pooled RR, 1.42; 95% CI, 1.31-1.53) and stroke mortality (pooled RR, 1.53; 95% CI, 1.18-1.99) in our meta-analyses. Relative risk of stroke incidence was as follows: females (pooled RR, 1.67; 95% CI, 1.44-1.92) and males (pooled RR, 1.13; 95% CI, 1.02-1.25). Relative risk of mortality was as follows: female (pooled RR, 1.41; 95% CI, 1.31-1.52) and males (pooled RR, 1.27; 95% CI, 1.20-1.34). For the risk of stroke mortality, the association between HUA and ischemic stroke (pooled RR, 1.39; 95% CI, 1.31-1.47) was more significant than that of hemorrhagic stroke (pooled RR, 1.13; 95% CI, 1.02-1.26). Our study confirms an association between HUA and risk of stroke, which is more pronounced in females.

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