Secular stroke trends: early life factors and future prospects

A preliminary spatial analysis of diagnosed stroke disease in Osun state, Nigeria

INTRODUCTION

There have been a number of clinical studies on diagnosed Stroke disease. However, there have been few studies on the geographical disparities for stroke. This study investigates the spatial pattern of stroke disease reflecting socio-demographic characteristics in the State.

METHODS

Stroke patients' admissions for 22 years (from 1990 to 2012) were examined. Their socio-demographic characteristics were extracted from their health records and analyzed. The location of the stroke patients were categorized by Local Governments Areas (LGAs). Spatial maps were generated and produced in a Geographical Information System (GIS) environment. It involves the analysis of the distribution of stroke cases in relation to their underlying population to determine the areas of high and low density of diagnosed cases across the state.

RESULTS

The result highlighted the spatial distribution of diagnosed stroke cases and also highlighted the areas of concern regarding their spatial distribution within the state. Social inequalities in stroke were persistent as incidence rates in urban areas (North) were around 3 times higher than in the rural areas (South). However, this could be due to better healthcare access in the urban areas than in the rural areas as there were disparities in the distribution of healthcare facilities involved in administering care to stroke patients in Osun State.

CONCLUSION

The outcome of this study appears to indicate that spatial inequalities in the access to Stroke healthcare is a concern that needs to be addressed in order to manage the disease adequately.

The SLC8 gene family of sodium-calcium exchangers (NCX) - structure, function, and regulation in health and disease

The SLC8 gene family encoding Na(+)/Ca(2+) exchangers (NCX) belongs to the CaCA (Ca(2+)/Cation Antiporter) superfamily. Three mammalian genes (SLC8A1, SLC8A2, and SLC8A3) and their splice variants are expressed in a tissue-specific manner to mediate Ca(2+)-fluxes across the cell-membrane and thus, significantly contribute to regulation of Ca(2+)-dependent events in many cell types. A long-wanted mitochondrial Na(+)/Ca(2+) exchanger has been recently identified as NCLX protein, representing a gene product of SLC8B1. Distinct NCX isoform/splice variants contribute to excitation-contraction coupling, long-term potentiation of the brain and learning, blood pressure regulation, immune response, neurotransmitter and insulin secretion, mitochondrial bioenergetics, etc. Altered expression and regulation of NCX proteins contribute to distorted Ca(2+)-homeostasis in heart failure, arrhythmia, cerebral ischemia, hypertension, diabetes, renal Ca(2+) reabsorption, muscle dystrophy, etc. Recently, high-resolution X-ray structures of Ca(2+)-binding regulatory domains of eukaryotic NCX and of full-size prokaryotic NCX have become available and the dynamic properties have been analyzed by advanced biophysical approaches. Molecular silencing/overexpression of NCX in cellular systems and organ-specific KO mouse models provided useful information on the contribution of distinct NCX variants to cellular and systemic functions under various pathophysiological conditions. Selective inhibition or activation of predefined NCX variants in specific diseases might have clinical relevance, although this breakthrough has not yet been realized. A better understanding of the underlying molecular mechanisms as well as the development of in vitro procedures for high-throughput screening of "drug-like" compounds may lead to selective pharmacological targeting of NCX variants.

Trends in Pregnancy Hospitalizations That Included a Stroke in the United States From 1994 to 2007

Background and Purpose—

Stroke is an important contributor to maternal morbidity and mortality, but there are no recent data on trends in pregnancy-related hospitalizations that have involved a stroke. This report describes stroke hospitalizations for women in the antenatal, delivery, and postpartum periods from 1994 to 1995 to 2006 to 2007 and analyzes the changes in these hospitalizations over time.

Methods—

Hospital discharge data were obtained from the Nationwide Inpatient Sample, developed as part of the Healthcare Cost and Utilization Project sponsored by the Agency for Healthcare Research and Quality. Pregnancy-related hospitalizations with stroke were identified according to the International Classification of Diseases, Ninth Revision. All statistical analyses accounted for the complex sampling design of the data source.

Results—

Between 1994 to 1995 and 2006 to 2007, the rate of any stroke (subarachnoid hemorrhage, intracerebral hemorrhage, ischemic stroke, transient ischemic attack, cerebral venous thrombosis, or unspecified) among antenatal hospitalizations increased by 47% (from 0.15 to 0.22 per 1000 deliveries) and among postpartum hospitalizations by 83% (from 0.12 to 0.22 per 1000 deliveries) while remaining unchanged at 0.27 for delivery hospitalizations. In 2006 to 2007, ≈32% and 53% of antenatal and postpartum hospitalizations with stroke, respectively, had concurrent hypertensive disorders or heart disease. Changes in the prevalence of these 2 conditions from 1994 to 1995 to 2006 to 2007 explained almost all of the increase in postpartum hospitalizations with stroke during the same period.

Conclusions—

Our results have demonstrated an increasing trend in the rate of pregnancy-related hospitalizations with stroke in the United States, especially during the postpartum period, from 1994 to 1995 to 2006 to 2007.

Constraint-induced movement therapy for upper extremities in stroke patients

BACKGROUND

In stroke patients, upper limb paresis affects many activities of daily life. Reducing disability is therefore a major aim of rehabilitation programmes for hemiparetic patients. Constraint-induced movement therapy (CIMT) is a current approach to stroke rehabilitation that implies the forced use and the massed practice of the affected arm by restraining the unaffected arm.

OBJECTIVES

To assess the efficacy of CIMT, modified CIMT (mCIMT), or forced use (FU) for arm management in hemiparetic patients.

SEARCH STRATEGY

We searched the Cochrane Stroke Group trials register (last searched June 2008), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2008), MEDLINE (1966 to June 2008), EMBASE (1980 to June 2008), CINAHL (1982 to June 2008), and the Physiotherapy Evidence Database (PEDro) (June 2008).

SELECTION CRITERIA

Randomised control trials (RCTs) and quasi-RCTs (qRCTs) comparing CIMT, mCIMT or FU with other rehabilitative techniques, or none.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified the identified trials according to the inclusion and exclusion criteria, assessed methodological quality and extracted data. The primary outcome was disability.

MAIN RESULTS

We included 19 studies involving 619 participants. The trials included participants who had some residual motor power of the paretic arm, the potential for further motor recovery and with limited pain or spasticity, but tended to use the limb little if at all. Only five studies had adequate allocation concealment. The majority of studies were underpowered (median number of included patients was 15) and we cannot rule out small-trial bias. Six trials (184 patients) assessed disability immediately after the intervention, indicating a significant standard mean difference (SMD) of 0.36, 95% confidence interval (CI) 0.06 to 0.65. For the most frequently reported outcome, arm motor function (11 studies involving 373 patients), the SMD was 0.72 (95% CI 0.32 to 1.12). There were only two studies that explored disability improvement after a few months of follow up and found no significant difference, SMD -0.07 (95% CI -0.53 to 0.40).

AUTHORS' CONCLUSIONS

CIMT is a multifaceted intervention: the restriction to the normal limb is accompanied by a certain amount of exercise of the appropriate quality. It is associated with a moderate reduction in disability assessed at the end of the treatment period. However, for disability measured some months after the end of treatment, there was no evidence of persisting benefit. Further randomised trials, with larger sample sizes and longer follow up, are justified.

Lifecourse social conditions and racial disparities in incidence of first stroke

PURPOSE

Some previous studies found excess stroke rates among black subjects persisted after adjustment for socioeconomic status (SES), fueling speculation regarding racially patterned genetic predispositions to stroke. Previous research was hampered by incomplete SES assessments, without measures of childhood conditions or adult wealth. We assess the role of lifecourse SES in explaining stroke risk and stroke disparities.

METHODS

Health and Retirement Study participants age 50+ (n = 20,661) were followed on average 9.9 years for self- or proxy-reported first stroke (2175 events). Childhood social conditions (southern state of birth, parental SES, self-reported fair/poor childhood health, and attained height), adult SES (education, income, wealth, and occupational status) and traditional cardiovascular risk factors were used to predict first stroke onset using Cox proportional hazards models.

RESULTS

Black subjects had a 48% greater risk of first stroke incidence than whites (95% confidence interval, 1.33-1.65). Childhood conditions predicted stroke risk in both blacks and whites, independently of adult SES. Adjustment for both childhood social conditions and adult SES measures attenuated racial differences to marginal significance (hazard ratio, 1.13; 95% CI, 1.00-1.28).

CONCLUSIONS

Childhood social conditions predict stroke risk in black and White American adults. Additional adjustment for adult SES, in particular wealth, nearly eliminated the disparity in stroke risk between black and white subjects.

Is the ‘Stroke Belt’ Worn From Childhood?

BACKGROUND AND PURPOSE

Most Stroke Belt studies define exposure based on residence at stroke onset. We assessed whether residence in the Stroke Belt during childhood confers extra stroke risk in adulthood, even among people who left the region.

METHODS

Stroke-free Health and Retirement Study participants (n=18 070) followed up (average, 8.4 years) for first stroke (1452 events) were classified as living in 1 of 7 Stroke Belt states in childhood or at study enrollment (average age, 63 years). We used Cox proportional-hazards models to compare stroke risk for people who had never lived in the Stroke Belt with those who had lived there at both ages, in childhood only, or in adulthood only.

RESULTS

Compared with never having lived in the Stroke Belt, the hazard ratio for Stroke Belt residence in both childhood and adulthood was 1.23 (95% CI, 1.06, 1.43) and for Stroke Belt residence in childhood only was 1.25 (95% CI, 1.02, 1.55). Stroke Belt residence at enrollment but not during childhood was not significantly related to stroke risk (hazard ratio=1.01; 95% CI, 0.70, 1.46), but the small sample in this group resulted in wide CIs. Results changed little after risk factor adjustment, including comprehensive adult socioeconomic measures. Subgroup analyses found similar patterns by sex and birth cohort. In contrast, blacks who had lived in the Stroke Belt in childhood only did not appear to have significantly elevated stroke risk compared with blacks who had never lived in the Stroke Belt.

CONCLUSIONS

The excess stroke risk for people who had lived in Stroke Belt states during childhood implicates early life exposures in the etiology of the Stroke Belt.