Association between migraine and exclusive breastfeeding: A cross-sectional study.

BACKGROUND: Medical conditions may preclude a mother from exclusively breastfeeding her infant; however, the association between migraine and the duration of exclusive breastfeeding is not well known. OBJECTIVE: To evaluate the association between migraine and the duration of exclusive breastfeeding in a representative sample of Canadian females. METHODS: We used the Canadian Community Health Survey, a cross-sectional survey, to identify females aged 20-49 years who delivered a baby in the previous 5 years. History of migraine was self-reported. Females reported if they breastfed their baby, and among those who did, they further reported the duration of exclusive breastfeeding. We evaluated the association between migraine and the rate of breastfeeding, and the duration of exclusive breastfeeding adjusting for selected covariates. RESULTS: We included 5282 females, of whom 862 (16.3%) had migraine. Compared to females without migraine, females with migraine were less likely to have high income (annual income >$80,000: 362 [42.0] vs. 2276 [51.6]), and more likely to have comorbid mood (176 [20.5] vs. 378 [8.6%]) and anxiety (196 [22.8%] vs. 406 [9.2%]) disorders. Migraine was not associated with breastfeeding (proportion of females who did not breastfeed, migraine vs. no migraine: 114/862 [13.2%] vs. 498/4420 [11.3%]; adjusted odds ratio 1.03; 0.74-1.27); however, females with migraine had lower odds (≥6 months of exclusive breastfeeding: 216/688 [31.4%] vs. 1325/3561 [37.2%]; adjusted odds ratio from ordinal shift analyses 0.84; 0.71-0.99) of longer duration of exclusive breastfeeding than females without migraine. CONCLUSION: Females with migraine exclusively breastfeed their infants for a shorter duration compared to females without migraine, suggesting the need to better support this population through education on the safety and benefits of exclusive breastfeeding and better access to safe and effective treatment of migraine in lactating females.

Does Self-Reported BMI Modify the Association Between Stroke and Depressive Symptoms?

BACKGROUND: Depressive symptoms are common in stroke survivors. While obesity has been associated with stroke and depression, its influence on the association between stroke and depressive symptoms is unknown. METHODS: Cross-sectional data from 2015 to 2016 Canadian Community Health Survey was used. History of stroke was self-reported and our outcome of interest was depressive symptoms in the prior 2 weeks, measured using the 9-item Patient Health Questionnaire. Self-reported body mass index (BMI) was modeled as cubic spline terms to allow for nonlinear associations. We used multivariable logistic regression to evaluate the association between stroke and depressive symptoms and added an interaction term to evaluate the modifying effect of BMI. RESULTS: Of the 47,521 participants, 694 (1.0%) had a stroke and 3314 (6.5%) had depressive symptoms. Those with stroke had a higher odds of depressive symptoms than those without (aOR = 3.13, 95% CI 2.48, 3.93). BMI did not modify the stroke-depressive symptoms association (P interaction = 0.242) despite the observed variation in stroke-depressive symptoms association across BMI categories,: normal BMI [18.5-25 kg/m2] (aOR† = 3.91, 95% CI 2.45, 6.11), overweight [25-30 kg/m2] (aOR† = 2.63, 95% CI 1.58, 4.20), and obese [>30 kg/m2] (aOR† = 2.76, 95% CI 1.92, 3.94). Similar results were found when depressive symptoms were modeled as a continuous measure. CONCLUSION: The association between stroke and depressive symptoms is not modified by BMI, needing additional work to understand the role of obesity on depression after stroke.

Attributable Costs of Stroke in Ontario, Canada and Their Variation by Stroke Type and Social Determinants of Health.

BACKGROUND: Estimates of attributable costs of stroke are scarce, as most prior studies do not account for the baseline health care costs in people at risk of stroke. We estimated the attributable costs of stroke in a universal health care setting and their variation across stroke types and several social determinants of health. METHODS: We undertook a population-based administrative database-derived matched retrospective cohort study in Ontario, Canada. Community-dwelling adults aged ≥40 years with a stroke between 2003 and 2018 were matched (1:1) on demographics and comorbidities with controls without stroke. Using a difference-in-differences approach, we estimated the mean 1-year direct health care costs attributable to stroke from a public health care payer perspective, accounting for censoring with a weighted available sample estimator. We described health sector-specific costs and reported variation across stroke type and social determinants of health. RESULTS: The mean 1-year attributable costs of stroke were Canadian dollars 33 522 (95% CI, $33 231-$33 813), with higher costs for intracerebral hemorrhage ($40 244; $39 193-$41 294) than ischemic stroke ($32 547; $32 252-$32 843). Most of these costs were incurred in acute care hospitals ($15 693) and rehabilitation facilities ($7215). Compared with all patients with stroke, the mean attributable costs were higher among immigrants ($40 554; $39 316-$41 793), those aged <65 years ($35 175; $34 533-$35 818), and those residing in low-income neighborhoods ($34 687; $34 054-$35 320) and lower among rural residents ($29 047; $28 362-$29 731). CONCLUSIONS: Our findings of high attributable costs of stroke, especially in immigrants, younger patients, and residents of low-income neighborhoods, can be used to evaluate potential health care cost savings associated with different primary stroke prevention strategies.

Safety and immunogenicity of the live-attenuated varicella vaccine in pediatric solid organ transplant recipients: A systematic review and meta-analysis.

This study aimed to synthesize the available evidence on the immunogenicity, safety, and effectiveness of live-attenuated varicella vaccine in solid organ transplant recipients. Medline and EMBASE were searched using predefined search terms to identify relevant studies. The included articles reported varicella vaccine administration in the posttransplant period in children and adults. A pooled proportion of transplant recipients who seroconverted and who developed vaccine-strain varicella and varicella disease was generated. Eighteen articles (14 observational studies and 4 case reports) were included, reporting on 711 transplant recipients who received the varicella vaccine. The pooled proportion was 88.2% (95% confidence interval 78.0%-96.0%, 13 studies) for vaccinees who seroconverted, 0% (0%-1.2%, 13 studies) for vaccine-strain varicella, and 0.8% (0%-4.9%, 9 studies) for varicella disease. Most studies followed clinical guidelines for administering live-attenuated vaccines, with criteria that could include being at least 1 year posttransplant, 2 months postrejection episode, and on low-dose immunosuppressive medications. Varicella vaccination in transplant recipients was overall safe in the included studies, with few cases of vaccine-strain-induced varicella or vaccine failure, and although it was immunogenic, the proportion of recipients who seroconverted was lower than that seen in the general population. Our data support varicella vaccination in select pediatric solid organ transplant recipients.

Association Between Stroke Severity and Serum Troponin in Acute Stroke.

Serum troponin is often elevated in patients with acute stroke and its mechanism is unknown. In a retrospective single-center cohort study, we evaluated the association between stroke severity and serum troponin in 187 patients with acute stroke using multivariable modified Poisson models. A one-point increase in the National Institutes of Health Stroke Scale (measure of stroke severity) was associated with a marginally higher serum troponin level in adjusted models (aIRR 1.03; 1.01-1.05, P = 0.001). The modest, yet potentially independent, association between stroke severity and serum troponins could suggest a neurogenic basis for a cardiac injury in patients with acute stroke.

Association Between Stroke and Subsequent Risk of Suicide: A Systematic Review and Meta-Analysis.

BACKGROUND AND PURPOSE: Poor mental health and depression are well-recognized sequelae of stroke; however, the association between stroke and subsequent risk of suicide is unknown. METHODS: We systematically searched MEDLINE, Embase, PsycINFO, and Google Scholar from their inception to September 15, 2020, using keywords and database-specific subjects. We independently adjudicated and selected observational studies that reported suicide attempts or death by suicide in stroke survivors and a comparison group, consisting either of people without a history of stroke or the general population. We evaluated study quality using the Newcastle Ottawa scale. Using random-effects meta-analysis, we calculated the pooled adjusted risk ratio (RR) of suicide in stroke survivors and separately calculated the pooled adjusted RR of suicide attempt and death by suicide. Using prespecified analyses, we explored study-level factors to explain heterogeneity. RESULTS: We screened 4093 articles and included 23 studies of fair quality, totaling over 2 million stroke survivors, of whom 5563 attempted suicide or died by suicide. Compared to the nonstroke group, the pooled adjusted RR of suicide in stroke survivors was 1.73 (95% CI, 1.53-1.96, I2=93%), with a significantly (P=0.03) higher adjusted risk of suicide attempt (RR, 2.11 [1.73-2.56]) than of death by suicide (RR, 1.61 [1.41-1.84]). A longer follow-up time in cohort studies was associated with a lower risk of suicide (RR, 0.97 [0.95-0.99] for every 1-year increase). CONCLUSIONS: Stroke should be considered as a risk factor for suicide. Comprehensive strategies to screen and treat depression and suicidal ideation in stroke survivors should be developed to reduce the burden of suicide in stroke survivors.

Stroke Incidence by Sex Across the Lifespan.

BACKGROUND AND PURPOSE: We evaluated the influence of age on the association between sex and the incidence of stroke or transient ischemic attack (TIA) using a population-based cohort from Ontario, Canada. METHODS: We followed a cohort of adults (≥18 years) without prior stroke from January 1, 2003 (cohort start date) to March 31, 2018, to identify incident events. We calculated hazard ratios (HRs), in women compared to men, of incident stroke or TIA, adjusted for demographics and comorbidities, overall and stratified by stroke type. We calculated piecewise adjusted HRs for each decade of age to evaluate the effect of age on sex differences in stroke incidence. RESULTS: We followed 9.2 million adults for a median of 15 years and observed 280,197 incident stroke or TIA events. Compared with men, women had an overall lower adjusted hazard of stroke or TIA (HR, 0.82 [95% CI, 0.82-0.83]), with similar findings across all stroke types except for subarachnoid hemorrhage (HR, 1.29 [95% CI, 1.24-1.33]). We found a U-shaped association between age and sex differences in the incidence of stroke or TIA: compared with men, the hazard of stroke was higher in women among those aged ≤30 years (HR, 1.26 [95% CI, 1.10-1.45]), lower among those between ages 40 and 80 years (eg, age 50-59, HR, 0.69 [95% CI, 0.68-0.70]), and similar among those aged ≥80 years (HR, 0.99 [95% CI, 0.98-1.01]). CONCLUSIONS: Overall, women have a lower hazard of stroke than men, but this association varies by age and across stroke types. Recognition of age-sex variations in stroke incidence can help guide prevention efforts to reduce stroke incidence in both men and women.

The association between loneliness and medication use in older adults.

BACKGROUND: Loneliness is common in older adults, and it is associated with unhealthy behaviours, including substance use. We evaluated the association between loneliness and self-reported use of opioids and benzodiazepines in older adults. METHODS: We used data from the Canadian Community Health Survey's 'Healthy Aging' sub-survey and included adults 65 years or older who administered their own medications. We classified individuals as lonely if they scored 6 or more on the three -item University of California, Los Angeles's Loneliness Scale. We used multinomial logistic regression models, adjusting for demographics and self-reported comorbidities, to describe the association between loneliness and daily or occasional use of opioids, benzodiazepines and non-opioid analgesics. We also explored the association between loneliness and polypharmacy. RESULTS: Our cohort included 15,302 older adults, of whom 2,096 (13.7%) were classified as lonely. Daily use of opioids (4.1%) and benzodiazepines (1.7%) were less common than daily use of non-opioid analgesics (33.9%). Lonely older adults had higher daily use of opioids (odds ratio [OR] 1.61, 1.31-1.98) and benzodiazepines (OR 1.66, 1.21-2.28), but not non-opioid analgesics (OR 1.05, 0.92-1.19). Loneliness was not associated with occasional use of opioids, benzodiazepines or non-opioid analgesics in older adults, but was associated with polypharmacy (OR 1.27, 1.06-1.52). CONCLUSIONS: Loneliness in older adults is associated with increased daily use of opioids and benzodiazepines. Further research should evaluate patient- and physician-level factors that mediate this association, and develop strategies to mitigate loneliness and its attendant adverse outcomes.

Sex differences in direct healthcare costs following stroke: a population-based cohort study.

BACKGROUND: The economic burden of stroke on the healthcare system has been previously described, but sex differences in healthcare costs have not been well characterized. We described the direct person-level healthcare cost in men and women as well as the various health settings in which costs were incurred following stroke. METHODS: In this population-based cohort study of patients admitted to hospital with stroke between 2008 and 2017 in Ontario, Canada, we used linked administrative data to calculate direct person-level costs in Canadian dollars in the one-year following stroke. We used a generalized linear model with a gamma distribution and a log link function to compare costs in women and men with and without adjustment for baseline clinical differences. We also assessed for an interaction between age and sex using restricted cubic splines to model the association of age with costs. RESULTS: We identified 101,252 patients (49% were women, median age [Q1-Q3] was 76 years [65-84]). Unadjusted costs following stroke were higher in women compared to men (mean ± standard deviation cost was $54,012 ± 54,766 for women versus $52,829 ± 59,955 for men, and median cost was $36,703 [$16,496-$72,227] for women versus $32,903 [$15,485-$66,007] for men). However, after adjustment, women had 3% lower costs compared to men (relative cost ratio and 95% confidence interval 0.97 [0.96,0.98]). The lower cost in women compared to men was most prominent among people aged over 85 years (p for interaction = 0.03). Women incurred lower costs than men in outpatient care and rehabilitation, but higher costs in complex continuing care, long-term care, and home care. CONCLUSIONS: Patterns of resource utilization and direct medical costs were different between men and women after stroke. Our findings inform public payers of the drivers of costs following stroke and suggest the need for sex-based cost-effectiveness evaluation of stroke interventions with consideration of costs in all care settings.

Association Between Immigration Status and Acute Stroke Care: A Retrospective Study.

Background and Purpose- Immigrants to high-income countries have a lower incidence of stroke compared with long-term residents; however, little is known about the care and outcomes of stroke in immigrants. Methods- We used linked clinical and administrative data to conduct a retrospective cohort study of adults seen in the emergency department or hospitalized with ischemic stroke or transient ischemic attack between July 1, 2003, and April 1, 2013, and included in the provincial stroke registry. We ascertained immigration status using immigration records and compared processes of stroke care delivery between immigrants (defined as those immigrating after 1985) and long-term residents. In the subgroup with ischemic stroke, we calculated inverse probability treatment weight (IPTW)-adjusted risk ratios for disability on discharge (modified Rankin Scale score of 3 to 5), accounting for demographic characteristics and comorbid conditions to compare outcomes between immigrants and long-term residents. Results- We included 34 987 patients with ischemic stroke or transient ischemic attack, of whom 2649 (7.6%) were immigrants. Immigrants were younger than long-term residents at the time of stroke/transient ischemic attack (median age 67 years versus 76 years; P<0.001). In the subgroup with ischemic stroke, there were no differences in stroke care delivery, except that a higher proportion of immigrants received thrombolysis than long-term residents (21.2% versus 15.5%; P<0.001). Immigrants with ischemic stroke had a higher adjusted risk of being disabled on discharge (adjusted risk ratio, 1.18; 95% CI, 1.13-1.22) compared to long-term residents. Conclusions- Stroke care is similar in Canadian immigrants and long-term residents. Future research is needed to confirm the observed association between immigration status and disability after stroke and to identify factors underlying the association.

Temporal Trends in the Unmet Health Care Needs of Canadian Stroke Survivors.

BACKGROUND: Stroke survivors have higher unmet health care needs than the general population. However, it is unclear whether such needs have changed over time, and whether these have been affected by the introduction of integrated systems of stroke care. METHODS: We used data from the Canadian Community Health Surveys between 2000 and 2014. We developed multivariable log-binomial generalized estimating equations to obtain adjusted risk ratios (aRRs) of unmet health care needs in stroke survivors compared to the general population, and over time. We conducted a difference in differences analysis to determine the association between the implementation of integrated systems of stroke care and unmet health care needs. RESULTS: Data from 350,084 respondents were included in the study; 8072 (2.3%) were stroke survivors. Compared to the general population, stroke survivors were more likely to report unmet health care needs (aRR 1.27; 95% CI, 1.22-1.32). The unmet health care needs reported by stroke survivors were lower after compared to before 2006 (15.8% vs. 31.9%, P < 0.001). After accounting for temporal trends, there was no association between the implementation of integrated systems of stroke care and change in unmet health care needs of stroke survivors. However, this requires cautious interpretation due to limitations in the data available for this study. CONCLUSIONS: Unmet health care needs of stroke survivors have reduced over time but remain higher than the general population. Future research should focus on identifying stroke- and policy-related factors to mitigate disparities in health care access for stroke survivors.

Delayed Thrombectomy Center Arrival is Associated with Decreased Treatment Probability.

BACKGROUND: Endovascular thrombectomy (EVT) is effective in reducing disability in selected patients with stroke and large vessel occlusion (LVO), but access to this treatment is suboptimal. AIM: We examined the proportion of patients with LVO who did not receive EVT, the reasons for non-treatment, and the association between time from onset and probability of treatment. METHODS: We conducted a retrospective cohort study of consecutive patients with acute stroke and LVO presenting between January 2017 and June 2018. We used multivariable log-binomial models to determine the association between time and probability of treatment with and without adjustment for age, sex, dementia, active cancer, baseline disability, stroke severity, and evidence of ischemia on computerized tomography. RESULTS: We identified 256 patients (51% female, median age 74 [interquartile range, IQR 63.5, 82.5]), of whom 59% did not receive EVT. The main reasons for not treating with EVT were related to occlusion characteristics or infarct size. The median time from onset to EVT center arrival was longer among non-treated patients (218 minutes [142, 302]) than those who were treated (180 minutes [104, 265], p = 0.03). Among patients presenting within 6 hours of onset, the relative risk (RR) of receiving EVT decreased by 3% with every 10-minute delay in arrival to EVT center (adjusted RR 0.97 CI95 [0.95, 0.99]). This association was not found in the overall cohort. CONCLUSIONS: The proportion of patients with acute stroke and confirmed LVO who do not undergo EVT is substantial. Minimizing delays in arrival to EVT center may optimize the delivery of this treatment.

The Association between Stroke, Integrated Stroke Systems, and the Employability and Productivity of Canadian Stroke Survivors.

BACKGROUND: Integrated stroke systems have been associated with reduced disability in stroke survivors, but their impact on employability and productivity (hours worked/week and hourly wages) of stroke survivors is unclear. METHODS: We used Canadian Community Health Surveys (2000-2014) to conduct a quasi-experimental study with the aim of determining the impact of stroke on employability and productivity, and whether the implementation of integrated stroke systems was associated with improvements in the employability and productivity of adult Canadian stroke survivors. Multivariable generalized Poisson regression models were used to determine the effect of stroke on employability; multivariable Heckman models were used to estimate the effect of stroke on productivity. A difference in differences analysis was used to determine the impact of stroke systems on the primary outcomes. RESULTS: The study sample included 400,797 respondents, of whom 5,786 (1.4%) were stroke survivors. Compared to the general population, stroke survivors were less likely to be employed (adjusted incidence rate ratio 0.62, 95% CI 0.59-0.66) and earned an hourly wage that was 5.3% lower (95% CI 1.1-9.3) and worked an average of 1.9 fewer hours per week (95% CI 0.9-2.9). Over the study period, the employability of stroke survivors improved but not productivity. After accounting for temporal changes in overall employment, there was no association between the implementation of integrated stroke systems and either employability or productivity. CONCLUSION: Employability of stroke survivors improved over the study period but remained lower than the general population, with no differences in provinces with and without integrated stroke systems.

Lost Productivity in Stroke Survivors: An Econometrics Analysis.

BACKGROUND: Stroke leads to a substantial societal economic burden. Loss of productivity among stroke survivors is a significant contributor to the indirect costs associated with stroke. We aimed to characterize productivity and factors associated with employability in stroke survivors. METHODS: We used the Canadian Community Health Survey 2011-2012 to identify stroke survivors and employment status. We used multivariable logistic models to determine the impact of stroke on employment and on factors associated with employability, and used Heckman models to estimate the effect of stroke on productivity (number of hours worked/week and hourly wages). RESULTS: We included data from 91,633 respondents between 18 and 70 years and identified 923 (1%) stroke survivors. Stroke survivors were less likely to be employed (adjusted OR 0.39, 95% CI 0.33-0.46) and had hourly wages 17.5% (95% CI 7.7-23.7) lower compared to the general population, although there was no association between work hours and being a stroke survivor. We found that factors like older age, not being married, and having medical comorbidities were associated with lower odds of employment in stroke survivors in our sample. CONCLUSIONS: Stroke survivors are less likely to be employed and they earn a lower hourly wage than the general population. Interventions such as dedicated vocational rehabilitation and policies targeting return to work could be considered to address this lost productivity among stroke survivors.

Proportion of Life Spent in Canada and the Incidence of Multiple Sclerosis in Permanent Immigrants.

BACKGROUND AND OBJECTIVES: While immigrants to high-income countries have a lower risk of multiple sclerosis (MS) compared with host populations, it is unknown whether this lower risk among immigrants increases over time. Our objective was to evaluate the association between proportion of life spent in Canada and the hazard of incident MS in Canadian immigrants. METHODS: We conducted a population-based retrospective cohort study in Ontario, using linked health administrative databases. We followed immigrants, who arrived in Ontario between 1985 and 2003, from January 1, 2003, to December 31, 2016, to record incident MS using a validated algorithm based on hospital admission or outpatient visits. We derived proportion of life spent in Canada based on age at arrival and time since immigration obtained from linked immigration records. We used multivariable proportional hazard models, adjusting for demographics and comorbidities, to evaluate the association between proportion of life in Canada and the incidence of MS, where proportion of life was modelled using restricted cubic spline terms. We further evaluated the role of age at migration (15 or younger vs older than 15 years), sex, and immigration class in sensitivity analyses. RESULTS: We included 1.5 million immigrants (49.9% female, mean age 35.9 [SD 14.2] years) who had spent a median of 20% (Q1-Q3 10%-30%) of their life in Canada. During a mean follow-up of 13.9 years (SD 1.0), 934 (0.44/100,000 person-years) were diagnosed with MS. Compared with the median, a higher risk of MS was observed at higher values of proportion of life spent (e.g., hazard ratio [70% vs 20% proportion of life] 1.38; 1.07-1.78). This association did not vary by sex (p(sex × proportion of life) = 0.70) or immigration class (p(immigration class × proportion of life) = 0.13). The results did not vary by age at migration but were statistically significant only at higher values of proportion of life for immigrants aged 15 years or younger at arrival. DISCUSSION: The risk of incident MS in immigrants varied with the proportion of life spent in Canada, suggesting an acculturation effect on MS risk. Further work is required to understand environmental and sociocultural factors driving the observed association.

Determinants, Prevention, and Incidence of Cardiovascular Disease Among Immigrant and Refugee Populations.

Immigration policies shape the composition, socioeconomic characteristics, and health of migrant populations. The health of migrants is also influenced by a confluence of social, economic, environmental, and political factors. Immigrants and refugees often face various barriers to accessing health care because of factors such as lack of familiarity with navigating the health care system, language barriers, systemic racism, and gaps in health insurance. Social determinants of health and access to primary care health services likely influence the burden of cardiovascular risk factors among immigrants. The relatively low burden of many cardiovascular risk factors in many immigrant populations likely contributes to the generally lower incidence rates of acute myocardial infarction, heart failure, and stroke in immigrants compared with nonimmigrants, although cardiovascular disease incidence rates vary substantially by country of origin. The "healthy immigrant effect" is the hypothesis that immigrants to high-income countries, such as Canada, are healthier than nonimmigrants in the host population. However, this effect may not apply universally across all immigrants, including recent refugees, immigrants without formal education, and unmarried immigrants. As unfolding sociopolitical events generate new waves of global migration, policymakers and health care providers need to focus on addressing social and structural determinants of health to better manage cardiovascular risk factors and prevent cardiovascular disease, especially among the most marginalized immigrants and refugees.