Increased risk of stroke in oral contraceptive users carried replicated genetic variants: a population-based case-control study in China

Incidence, lethality, and post-stroke functional status in different Brazilian macro-regions: The SAMBA study (analysis of stroke in multiple Brazilian areas)

Background

Stroke is the second leading cause of death in Brazil. The social and financial burden of stroke is remarkable; however, the epidemiological profile remains poorly understood.

Objective

The aim of this study was to report the incidence, lethality, and functional status at 30 and 90 days post-stroke in the cities of different Brazilian macro-regions.

Methods

This is an observational, prospective, and population-based study, led in Canoas (South), Joinville (South, reference center), Sertãozinho (Southeast), and Sobral (Northeast) in Brazil. It was developed according to the three-step criteria recommended by the World Health Organization to conduct population-based studies on stroke. Using different sources, all hospitalized and ambulatory patients with stroke were identified and the same criteria were kept in all cities. All first events were included, regardless of sex, age, or type of stroke. Demographic and risk factor data were collected, followed by biochemical, electrocardiographic, and radiological test results. Functional status and lethality were obtained using the mRankin scale through telephonic interview (validated Brazilian version).

Results

In 1 year, 932 stroke cases were registered (784 ischemic stroke, 105 hemorrhagic stroke, and 43 subarachnoid hemorrhage). The incidence rates per 100,000 inhabitants, adjusted for the world population, were 63 in Canoas, 106 in Joinville, 72 in Sertãozinho, and 96 in Sobral. The majority (70.8%) were followed for 90 days. Kaplan-Meier curves showed that 90-day survival was different among cities. Sobral, which has the lowest socioeconomic indexes, revealed the worst results in terms of lethality and functional status.

Conclusion

This study expands the knowledge of stroke epidemiology in Brazil, a middle-income country with enormous socioeconomic and cultural diversity. The discrepancy observed regarding the impact of stroke in patients from Joinville and Sobral highlights the need to improve the strategic allocation of resources to meet the health priorities in each location.

Genetic association of ANRIL with susceptibility to Ischemic stroke: A comprehensive meta-analysis

Background

Ischemic stroke (IS) is a complex polygenic disease with a strong genetic background. The relationship between the ANRIL (antisense non-coding RNA in the INK4 locus) in chromosome 9p21 region and IS has been reported across populations worldwide; however, these studies have yielded inconsistent results. The aim of this study is to clarify the types of single-nucleotide polymorphisms on the ANRIL locus associated with susceptibility to IS using meta-analysis and comprehensively assess the strength of the association.

Methods

Relevant studies were identified by comprehensive and systematic literature searches. The quality of each study was assessed using the Newcastle-Ottawa Scale. Allele and genotype frequencies were extracted from each of the included studies. Odds ratios with corresponding 95% confidence intervals of combined analyses were calculated under three genetic models (allele frequency comparison, dominant model, and recessive model) using a random-effects or fixed-effects model. Heterogeneity was tested using the chi-square test based on the Cochran Q statistic and I2 metric, and subgroup analyses and a meta-regression model were used to explore sources of heterogeneity. The correction for multiple testing used the false discovery rate method proposed by Benjamini and Hochberg. The assessment of publication bias employed funnel plots and Egger’s test.

Results

We identified 25 studies (15 SNPs, involving a total of 11,527 cases and 12,216 controls maximum) and performed a meta-analysis. Eight SNPs (rs10757274, rs10757278, rs2383206, rs1333040, rs1333049, rs1537378, rs4977574, and rs1004638) in ANRIL were significantly associated with IS risk. Six of these SNPs (rs10757274, rs10757278, rs2383206, rs1333040, rs1537378, and rs4977574) had a significant relationship to the large artery atherosclerosis subtype of IS. Two SNPs (rs2383206 and rs4977574) were associated with IS mainly in Asians, and three SNPs (rs10757274, rs1333040, and rs1333049) were associated with susceptibility to IS mainly in Caucasians. Sensitivity analyses confirmed the reliability of the original results. Ethnicity and individual studies may be the main sources of heterogeneity in ANRIL.

Conclusions

Our results suggest that some single-nucleotide polymorphisms on the ANRIL locus may be associated with IS risk. Future studies with larger sample numbers are necessary to confirm this result. Additional functional analyses of causal effects of these polymorphisms on IS subtypes are also essential.

Cerebrovascular disease in women

Cerebrovascular disease is a major cause of morbidity, mortality, and disability in women. The spectrum of disease differs between men and women, with women being particularly vulnerable to certain conditions, especially during specific periods of life such as pregnancy. There are several unique risk factors for cerebrovascular disease in women, and the influence of some traditional risk factors for stroke is stronger in women. Moreover, disparities persist in representation of women in clinical trials, acute intervention, and stroke outcomes. In this review, we aimed to explore the epidemiology, etiologies, and management of cerebrovascular disease in women, highlighting some of these differences and the growing need for sex-specific management guidelines and health policies.

Oral Contraceptive Use and Increased Risk of Stroke: A Dose-Response Meta-Analysis of Observational Studies

Background: Oral contraceptive (OCP) use might increase the risk of stroke in women. We examined a possible dose–response relation between OCP use and the risk of stroke in young and middle-aged women.

Methods: A retrieval of PubMed and EMBASE databases was performed. We selected observational studies that reported odds ratios (ORs) with 95% confidence intervals (CIs) for the risk of stroke in OCP users. A two-stage dose–response analysis was conducted using the random-effects model and the restricted spline model.

Results: A total of 6 cohort studies and 12 case–control studies were included, which involved 2,143,174 participants and 11,661 cases of stroke including ischemic stroke (IS), hemorrhagic stroke (HS), and stroke of unknown origin. The pooled ORs of total stroke were 1.19 (95% CI, 1.16–1.23) for every 10-μg increment in estrogen dosage, 1.20 (95% CI, 1.05–1.37) for every 5-years increment in duration of OCP use, and 0.82 (95% CI, 0.68–0.98) for every 5-years increment in duration of OCP cessation. The ORs of IS were 1.20 (95% CI, 1.17–1.22) in estrogen dosage, 1.24 (95% CI, 1.04–1.49) in duration of OCP use, and 0.78 (95% CI, 0.67–0.92) in duration of OCP cessation. The ORs of HS were 1.10 (95% CI, 1.04–1.16) in estrogen dosage, 1.13 (95% CI, 0.93–1.36) in duration of OCPs, and 0.71 (95% CI, 0.55–0.92) in duration of OCP cessation. The pooled ORs of total stroke from prospective studies (1.12; 95% CI, 1.01–1.24) were lower than those from retrospective studies (1.30; 95% CI, 1.01–1.67).

Conclusions: The higher estrogen dosage significantly increased the risks of total stroke, IS, and HS, respectively. The longer duration of OCP use significantly increased the risks of total stroke and IS, but its effects on HS risk were marginal. The longer duration of OCP cessation significantly decreased the risks of total stroke, IS, and HS, respectively. These findings affirm the contribution of estrogen dose and duration of OCP use to the increased risk of stroke, which may be critical for the instruction of OCP use and the prevention and management of cerebrovascular diseases.

Associations between Aquaglyceroporin Gene Polymorphisms and Risk of Type 2 Diabetes Mellitus

Objectives

AQP7 and AQP9 represent glycerol channel in adipose tissue and liver and have been associated with metabolic diseases. We aimed to investigate the associations between genetic variants in AQP7 and AQP9 genes and the risk of type 2 diabetes (T2DM) in Chinese population.

Methods

Blood samples were drawn from 400 T2DM patients and 400 age- and gender-matched controls. Genomic DNA was extracted by proteinase K digestion and phenol–chloroform extraction. Genotyping of 5 single nucleotide polymorphisms (SNPs) in AQP7 (rs2989924, rs3758269, and rs62542743) and AQP9 (rs57139208, rs16939881) was performed by the polymerase chain reaction assay with TaqMan probes.

Results

The subjects with rs2989924 GA+AA genotypes had 1.47-fold increased risk of T2DM (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.06-2.04), compared to those with GG genotype, and this association remained significant after adjustment for covariates (OR 1.66, 95% CI 1.07-2.57). When compared with rs3758269 CC genotype, the subjects with CT+TT genotypes had 45% decreased T2DM risk after multivariate adjustment (OR 0.55, 95% CI 0.35-0.85). The associations were evident in elder and overweight subjects and those with central obesity. No association was observed between AQP9 SNPs and T2DM risk.

Conclusions

AQP7 SNP rs2989924 and rs3758269 were associated with T2DM risk in Chinese Han population.

INTERMACS Analysis of Stroke During Support With Continuous-Flow Left Ventricular Assist Devices: Risk Factors and Outcomes

OBJECTIVES

This study sought to evaluate predictors of stroke during left ventricular assist device (LVAD) support from data available prior to implantation, and quantify stroke-related morbidity and mortality.

BACKGROUND

Stroke is a major complication after LVAD. Pre-implant factors that influence stroke are not well understood.

METHODS

We evaluated all patients in INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) who were implanted with continuous flow LVADs from May 1, 2012, to March 31, 2015. Pre-operative risk factors for stroke and stroke incidence, morbidity, and mortality were analyzed.

RESULTS

During the study period, 7,112 patients underwent continuous flow LVAD placement. Median follow-up was 9.79 months (range 0.02 to 34.96 months). Of all patients, 752 (10.57%) had at least 1 stroke, with an incidence rate of 0.123 strokes per patient-year. A total of 447 (51.38%) strokes were ischemic and 423 (48.62%) were hemorrhagic. Patients with hemorrhagic stroke had worse survival than those with ischemic strokes (30-day survival: 45.3% vs. 80.7%; p < 0.001). Of patients with a first stroke, 13% had a second stroke. Pre-implant predictors of stroke were female sex (hazard ratio [HR]: 1.51; 95% confidence interval [CI]: 1.25 to 1.82; p < 0.001), pre-implant systolic blood pressure (HR: 1.01; 95% CI: 1.00 to 1.01; p = 0.002), heparin-induced thrombocytopenia (HR: 3.68; 95% CI: 1.60 to 8.47; p = 0.002), intra-aortic balloon pump (HR: 1.21; 95% CI: 1.01 to 1.46; p = 0.043), and primary cardiac diagnosis (ischemic/other/unknown) (p = 0.040).

CONCLUSIONS

Despite improvements in LVAD technology, stroke-related morbidity and mortality is substantial. Further investigation is necessary to decrease the risk of this devastating complication.

Association between oral contraceptives and risk of hemorrhagic stroke: a meta-analysis of observational studies

OBJECTIVES

To estimate the risk of hemorrhagic stroke associated with current use of oral contraceptives (OCs), and to further depict how the risk was affected by study characteristics.

METHODS

We searched PubMed, Embase, and Cochrane Library for relevant articles published up to February 2017 that examined the association between OC use and risk of hemorrhagic stroke. Two investigators independently reviewed articles based on inclusion criteria. The Newcastle-Ottawa scale was employed to evaluate quality of studies. Random-effects meta-analysis model was used to generate summary risk estimates.

RESULTS

Fifteen independent studies (5 cohort studies and 10 case-control studies) with 4271 hemorrhagic stroke cases were included in this meta-analysis. The overall summary odds ratio (OR) for hemorrhagic stroke (HS) in relation to current OC use was 1.39 [95% confidence interval (CI), 1.05-1.83]. Subgroup analyses on hemorrhagic stroke types showed that OC use was associated with subarachnoid hemorrhage (SAH) (OR 1.68; 95% CI 1.21-2.12), but not with intracerebral hemorrhage (ICH) (OR 0.92; 95% CI 0.33-2.54). The risk of hemorrhagic stroke was increased slightly among current OC users with high-dose estrogen (OR 1.60; 95% CI 1.12-2.27). The risk of hemorrhagic stroke was further increased in OC users with additional risk factors including current smoking, hypertension, and history of migraine.

CONCLUSIONS

This meta-analysis of observational studies suggests that current use of OCs could contribute to a small increased risk of hemorrhagic stroke, and the increased risk is related to subarachnoid hemorrhage, but not intracerebral hemorrhage.

Combined oral contraceptives: the risk of myocardial infarction and ischemic stroke

BACKGROUND

Combined oral contraceptives (COCs) have been associated with an increased risk of arterial thrombosis, i.e. myocardial infarction or ischemic stroke. However, as these diseases are rare in young women and as many types of combined oral contraception exist, the magnitude of the risk and the effect of different hormonal contents of COC preparations remain unclear.

OBJECTIVES

To estimate the risk of myocardial infarction or ischemic stroke in users compared with non-users of different types, doses and generations of combined oral contraception.

SEARCH METHODS

We searched electronic databases (MEDLINE (1966 to July 08, 2015), EMBASE (1980 to July 08, 2015), Popline (1970 to July 08, 2015) and LILACS (1985 to July 08, 2015) for eligible studies, without language restrictions.

SELECTION CRITERIA

We included observational studies that recruited women in the reproductive age group (18 to 50 years) and compared the risk of myocardial infarction or ischemic stroke between users and non-users of COCs.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected relevant studies and extracted data. We pooled relative risks ()(combined odds ratios and one incidence rate ratio) and 95% confidence intervals (CIs) for myocardial infarction or ischemic stroke in users versus non-users of COCs.We combined the outcomes of myocardial infarction and ischemic stroke and also analysed these outcomes separately. Analyses were stratified according to estrogen dose and progestagen type.

MAIN RESULTS

In total, we identified 1298 publications through the search strategy. We included 28 publications reporting on 24 studies. COC users were at increased risk of myocardial infarction or ischemic stroke compared with non-users: relative risk (RR) 1.6 (95% CI 1.3-1.9).These RRs were similar for myocardial infarction (1.6, 95% CI 1.2 to 2.1) and ischemic stroke (1.7, 95% CI 1.5 to 1.9). The risks did not vary clearly according to the generation of progestagen or according to progestagen type. When we stratified preparations according to estrogen dose, the risk of myocardial infarction or ischemic stroke seemed to increase with higher doses of estrogen.

AUTHORS' CONCLUSIONS

This meta-analysis showed that the risk of myocardial infarction or ischemic stroke was 1.6-fold increased in women using COCs . The risk was highest for pills with > 50 microgram estrogen. When combined with the results of studies on the risk of venous thrombosis in COC users, it seems that the COC pill containing levonorgestrel and 30 μg of estrogen is the safest oral form of hormonal contraception.

Pai-1 gene variants and COC use are associated with stroke risk: a case-control study in the Han Chinese women

Genetic variants of plasminogen activator inhibitor type 1 (PAI-1) gene have been suggested to influence the PAI-1 transcription activity and PAI-1 levels as well as might be involved in the pathophysiology of stroke. The aims of this study are to investigate whether the polymorphisms at the PAI-1 gene are associated with the risk of stroke and to explore the combined effects of PAI-1 variants and combined oral contraceptive (COC) use for stroke risk. We conducted a nested case-control study using 453 first-ever female stroke cases and 919 age- and region-matched controls that were recruited from our prospective surveillance cohort. SNP rs1799889 was genotyped by allele-specific polymerase chain reaction (PCR), and SNPs rs7242 and rs2227631 were detected by the TaqMan SNP genotyping assay. We identified that rs1799889 5G allele conferred a protective effect against ischemic stroke while 4G allele conferred an increased risk of ischemic stroke. But we failed to suggest associations of rs7242 and rs2227631. COC users had a 1.31-fold (OR=1.31, 95% CI=1.01-1.71) increased risk of stroke compared with the non-users. Furthermore, COC users with rs1799889 4G5G/5G5G genotype had a decreased risk of ischemic stroke (OR=0.53, 95% CI=0.34-0.83). Moreover, haplotype G-5G-T was associated with an increased risk of overall stroke (OR=1.28, 95% CI=1.01-1.62). In contrast, haplotype A-4G-G and haplotype G-5G-T were slightly associated with the protection from ischemic stroke (OR=0.61, 95% CI=0.46-0.82; OR=0.61, 95% CI=0.44-0.85, respectively). The study assessed the associations of three PAI-1 SNPs and also suggested combined effects of these PAI-1 gene variants and COC use on stroke risk in the Han Chinese women.

Guidelines for the prevention of stroke in women: a statement for healthcare professionals from the American Heart Association/American Stroke Association

PURPOSE

The aim of this statement is to summarize data on stroke risk factors that are unique to and more common in women than men and to expand on the data provided in prior stroke guidelines and cardiovascular prevention guidelines for women. This guideline focuses on the risk factors unique to women, such as reproductive factors, and those that are more common in women, including migraine with aura, obesity, metabolic syndrome, and atrial fibrillation.

METHODS

Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council's Scientific Statement Oversight Committee and the AHA's Manuscript Oversight Committee. The panel reviewed relevant articles on adults using computerized searches of the medical literature through May 15, 2013. The evidence is organized within the context of the AHA framework and is classified according to the joint AHA/American College of Cardiology and supplementary AHA Stroke Council methods of classifying the level of certainty and the class and level of evidence. The document underwent extensive AHA internal peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the AHA Science Advisory and Coordinating Committee.

RESULTS

We provide current evidence, research gaps, and recommendations on risk of stroke related to preeclampsia, oral contraceptives, menopause, and hormone replacement, as well as those risk factors more common in women, such as obesity/metabolic syndrome, atrial fibrillation, and migraine with aura.

CONCLUSIONS

To more accurately reflect the risk of stroke in women across the lifespan, as well as the clear gaps in current risk scores, we believe a female-specific stroke risk score is warranted.