Sex-related time-dependent variations in post-stroke survival--evidence of a female stroke survival advantage

Female survival advantage relates to male inferiority rather than female superiority: A hypothesis based on the impact of age and stroke severity on 1-week to 1-year case fatality in 40,155 men and women

BACKGROUND

It is generally believed that differences in age, stroke characteristics, and cardiovascular risk factors account for observed sex-specific differences in stroke survival.

OBJECTIVES

We aimed to study female stroke survival advantage before and after the average age of menopause, and whether female survival advantage applies only to patients for whom stroke is the most likely cause of death.

METHODS

The Danish National Indicator Project, a registry designed to list all hospitalized stroke patients in Denmark beginning in March 2001, had 40,155 registered patients as of February 2007. All registered patients had undergone evaluation including stroke severity (as measured by the Scandinavian Stroke Scale [SSS], using a total score of 0-58, in which lower scores indicate more severe strokes), computed tomography, and cardiovascular risk factors. Patients were followed from admission until death or censoring. Case fatality (stratified by 1 week, 1 month, 3 months, and 1 year) in men and women was correlated with age and stroke severity. Adjustment for cardiovascular risk factors was performed by means of multivariate regression analysis.

RESULTS

A total of 20,854 (51.9%) men and 19,301 (48.1%) women were registered. Women were significantly older than men at the time of stroke (74.5 vs 69.7 years, respectively; P < 0.001) and had signficantly more severe strokes, as expressed by the mean SSS score (39.6 vs 43.3; P < 0.001). Stratification of 1-week to 1-year case fatality according to age and stroke severity indicated that women survived significantly better than men from the mid-fifties onward, when controlling for age, stroke severity, and cardiovascular risk factor profile. The observed female survival advantage increased with age. The female survival advantage was seen in patients with severe as well as mild strokes, but not in those younger than age 50 years.

CONCLUSIONS

Our findings dispute the effects of female sex hormones as the underlying cause of female survival superiority over men. Instead, we propose the hypothesis that the progressive deficiency of male sex hormones (testosterone), beginning in men in middle age, is the underlying cause of the gap in survival rates between men and women. Accordingly, the female survival advantage is rooted in male inferiority rather than innate female superiority.

Age- and gender-specific prevalence of cardiovascular risk factors in 40,102 patients with first-ever ischemic stroke: a Nationwide Danish Study

BACKGROUND AND PURPOSE

We describe the prevalence of cardiovascular risk factors at stroke onset in men and women of all ages.

METHODS

A registry started in 2001, designed to register all hospitalized stroke patients in Denmark, now holds 40,102 patients with first-ever ischemic stroke. Patients underwent evaluation including stroke severity (Scandinavian Stroke Scale), CT, and cardiovascular risk factors: hypertension, atrial fibrillation, diabetes mellitus, intermittent arterial claudication, previous myocardial infarction, body mass index, smoking, and alcohol consumption. We estimated the independent effect of gender and age on prevalence of cardiovascular risk factors and calculated age and gender-specific prevalence rates for each risk factor.

RESULTS

The register contained 47.9% women and 52.1% men. Men had more often diabetes mellitus, previous myocardial infarction, intermittent arterial claudication, and over the limit alcohol consumption. Women had more often hypertension and obesity. Atrial fibrillation and smoking were equally frequent in both genders. Age stratification revealed that the lifestyle cardiovascular risk factors smoking, alcohol, and obesity were more common in the younger patients with stroke (< 60 years), whereas prevalence of hypertension, diabetes mellitus, myocardial infarction, intermittent arterial claudication, and, in men, also atrial fibrillation decreases in the elderly (> 70 to 80 years), the decrease being generally more pronounced in men than in women.

CONCLUSIONS

Cardiovascular risk factors were generally more prevalent in men. Lifestyle cardiovascular risk factors were more common in the young. Prevalence of hypertension, diabetes mellitus, coronary heart disease, and, in men, also atrial fibrillation go down after the age of 70 to 80 years.

A review on sex differences in stroke treatment and outcome

BACKGROUND

Beyond epidemiological differences, it has been controversial whether any important sex differences exist in the treatment of stroke. In this review paper, the following areas are covered: thrombolysis, stroke unit care, secondary prevention, surgical treatment, and rehabilitation. Additionally, symptoms at stroke onset, as well as outcome measures, such as death, dependency, stroke recurrence, quality of life, and depression are reviewed.

METHODS

Search in PubMed, tables-of-contents, review articles, and reference lists after studies that include information about sex differences in stroke care.

RESULTS

Ninety papers are included in this review. Women suffer more from cortical and non-traditional symptoms. Men and women benefit equally from thrombolysis and stroke unit care. Women with cardioembolic strokes may benefit more from anticoagulant therapy. Most studies have not found any tendency towards sexism in the choice of treatment. Post-stroke depression and low quality-of-life seem to be more common among women. Mortality rates are higher among men in some studies, while long-term ADL-dependency seems to be more common among women.

CONCLUSIONS

Sex differences in stroke treatment and outcome are small, with no unequivocal proof of sex discrimination. Women have less favourable functional outcome because of higher age at stroke onset and more severe strokes.

Gender differences in rehabilitation outcomes among older Chinese patients

Although gender differences have been demonstrated in cardiac and stroke rehabilitation, it remains unclear whether there are gender differences in geriatric rehabilitation. The purpose of this study is to investigate the relationship between gender and rehabilitation outcomes. We studied 1795 patients in two convalescence hospitals in Hong Kong. We defined absolute functional and motor gains as Barthel Index (BI) efficacy and Elderly Mobility Scale (EMS) efficacy while BI and EMS efficiency were efficacy divided by the length of stay. Satisfactory motor and functional outcomes were defined as discharge EMS ≥ 15 and BI ≥ 75. Compared with men, women had higher BI but lower EMS on admission and discharge. EMS and BI efficacy and efficiency were similar in both sexes. Female gender was a significant negative predictor for satisfactory motor outcome (p=0.0002) but a positive predictor for functional outcome (p=0.0007). Other predictors for satisfactory motor outcome were: age (p<0.001); urinary incontinence (p=0.0049); living at home (p=0.0056); admission EMS (p<0.001); admission BI (p=0.044). Other predictors for satisfactory functional outcome were: age (p=0.009); infection other than chest (p=0.047); urinary incontinence (p<0.001); Mini Mental State Examination (MMSE) (p=0.0004); admission EMS (p=0.005); BI (p<0.001). Women achieved a better functional outcome but a poorer motor outcome on discharge. Female gender was a positive predictor for functional outcome but a negative factor for motor outcome.

Excess mortality in men compared with women following a hip fracture. National analysis of comedications, comorbidity and survival

INTRODUCTION

osteoporosis is a common disease, and the incidence of osteoporotic fractures is expected to rise with the growing elderly population. Immediately following, and probably several years after a hip fracture, patients, both men and women, have a higher risk of dying compared to the general population regardless of age. The aim of this study was to assess excess mortality following hip fracture and, if possible, identify reasons for the difference between mortality for the two genders.

METHODS

this is a nationwide register-based cohort study presenting data from the National Hospital Discharge Register on mortality, comorbidity and medication for all Danish patients (more than 41,000 persons) experiencing a hip fracture between 1 January 1999 and 31 December 2002. Follow-up period was until 31 December 2005.

RESULTS

we found a substantially higher mortality among male hip fracture patients than female hip fracture patients despite men being 4 years younger at the time of fracture. Both male and female hip fracture patients were found to have an excess mortality rate compared to the general population. The cumulative mortality at 12 months among hip fracture patients compared to the general population was 37.1% (9.9%) in men and 26.4% (9.3%) in women. In the first year, the risk of death significantly increased for women with increasing age (hazard ratio, HR: 1.06, 95% confidence interval, CI: 1.06-1.07), the number of comedications (HR 1.04, 95% CI 1.03-1.05) and the presence of specific Charlson index components and medications described below. For men, age (HR 1.07, 95% CI 1.07-1.08), number of comedications (HR 1.06, 95% CI 1.04-1.07) and presence of different specific Charlson index components and medications increased the risk. Long-term survival analyses revealed that excess mortality for men compared with women remained strongly significant (HR 1.70, 95% CI 1.65-1.75, P < 0.001), even when controlled for age, fracture site, the number of medications, exposure to drug classes A, C, D, G, J, M, N, P, S and for chronic comorbidities.

CONCLUSION

excess mortality among male patients cannot be explained by controlling for known comorbidity and medications. Besides gender, we found higher age and multimorbidity to be related to an increased risk of dying within the first year after fracture; acute complications might be one of the explanations. This study emphasises the need for particular rigorous postoperative diagnostic evaluation and treatment of comorbid conditions in the male hip fracture patient.

Oestradiol and insulin-like growth factor-1 reduce cell loss after global ischaemia in middle-aged female rats

Whereas the ability of oestradiol and insulin-like growth factor (IGF)-1 to afford neuroprotection against ischaemia-induced neuronal death in young female and male rodents is well established, the impact of IGF-1 in middle-aged animals is largely unknown. The present study assessed the efficacy of oestradiol and IGF-1 with respect to reducing neuronal death after transient global ischaemia in middle-aged female rats after 8 weeks of hormone withdrawal. Rats were ovariohysterectomised and implanted 8 weeks later with an osmotic mini-pump delivering IGF-1 or saline into the lateral ventricle. Some rats also received physiological levels of oestradiol by subcutaneous pellet. Two weeks later, rats were subjected to global ischaemia or sham operation. Surviving hippocampal CA1 neurones were quantified. Ischaemia produced massive CA1 cell death compared to sham-operated animals, which was evident at 14 days. Significantly more neurones survived in animals treated with either oestradiol or IGF-1, but simultaneous treatment produced no additive effect. IGF-1, an endogenous growth factor, may be a clinically useful therapy in preventing human brain injury, with neuroprotective equivalence to oestradiol but without the harmful side-effects.

Three-year survival and stroke recurrence rates in patients with primary intracerebral hemorrhage

BACKGROUND AND PURPOSE

There are few studies on the prognosis after primary intracerebral hemorrhages, and they reported big differences in mortality rates. Our aim was to evaluate mortality and stroke recurrence rates in relation to hemorrhage characteristics, demographic and clinical factors, in a large unselected patient cohort.

METHODS

We analyzed consecutive cases of first-ever primary intracerebral hemorrhages from 1993 to 2000 in a prospective stroke register covering the Malmö region, Sweden (population approximately 250 000). Mortality rates during 28 days and 3 years of follow-up and recurrence rates were analyzed.

RESULTS

A total of 474 cases were identified (46% women). In patients <75 years of age, 20% of the women and 23% of the men died within 28 days (P=0.38). The corresponding figures in patients >or=75 years were 26% and 41%, respectively (P=0.02). Male sex was an independent risk factor both for 28-day (OR, 1.5; 95% CI, 1.008 to 2.2) and 3-year mortality (OR, 1.7; 95% CI, 1.3 to 2.3). Other independent predictors of death were high age, central and brain stem hemorrhage location, intraventricular hemorrhage, increased volume, and decreased consciousness level. The recurrence rate was 5.1 per 100 person-years, 2.3 per 100 person-years for intracerebral hemorrhage and 2.8 per 100 person-years for cerebral infarction. Only age >65 years was significantly related to recurrent stroke.

CONCLUSIONS

Women had better survival than men after primary intracerebral hemorrhages. The difference is largely explained by a higher 28-day mortality in male patients >75 years. However, the underlying reasons are yet to be explored.

Sex differences in stroke: epidemiology, clinical presentation, medical care, and outcomes

Stroke has a greater effect on women than men because women have more events and are less likely to recover. Age-specific stroke rates are higher in men, but, because of their longer life expectancy and much higher incidence at older ages, women have more stroke events than men. With the exception of subarachnoid haemorrhage, there is little evidence of sex differences in stroke subtype or severity. Although several reports found that women are less likely to receive some in-hospital interventions, most differences disappear after age and comorbidities are accounted for. However, sex disparities persist in the use of thrombolytic treatment (with alteplase) and lipid testing. Functional outcomes and quality of life after stroke are consistently poorer in women, despite adjustment for baseline differences in age, prestroke function, and comorbidities. Here, we comprehensively review the epidemiology, clinical presentation, medical care, and outcomes of stroke in women.