e141Abstracts / Journal of the American Society of Hypertension 8(4S) (2014) e139–e141

In vitro, UCP2 gene silencing in renal mesangial cells led to increased rate

of reactive oxygen species generation, increased inflammation, increased

apoptosis and necrosis, and reduced cell vitality.

In conclusion, high-salt diet downregulates the antioxidant UCP2-depen-

dent mechanism in kidneys of SHRsp, but not of stroke-resistant SHR.

UCP2 appears to be a key protein for prevention of oxidative stress damage

in the kidneys.

Keywords: UCP2; stroke-prone spontaneously hypertensive rat

P-253

Unmasking silent atrial fibrillation in high blood pressure patients

with dual-chamber cardiac devices: unmasking stroke risk

Juan Benezet-Mazuecos,1 Marcelino Cortes,1 Jose Manuel Rubio,1

Adolfo de la Fuente,2 Jose Antonio Iglesias,1 Soraya Calle,1

Juan Jose de la VIeja,1 Jeronimo Farre.1 1Fundaci�on Jim�enez D�ıaz-IDC,

Madrid, Spain; 2MD Anderson Cancer Center Madrid, Madrid, Spain

Background: An assessment of the prevalence of silent paroxysmal AF

represents a challenge, since the arrhythmia may be brief, completely

asymptomatic and difficult to detect. Cardiac electronic devices have

shown reliable atrial fibrillation (AF) detection as atrial high rate episodes

(AHRE). The presence of AHRE > 5 min have been related to increased

risk of stroke. A high proportion of ischemic brain lesions could be

subclinical.

Methods: We analyzed prospectively the incidence of AHRE > 5 min

compatible with AF in a population of high blood pressure patients without

history of previous AF with dual-chamber cardiac devices after at least 3

months of follow-up and the presence of ischemic brain lesions on CT-

scan.

Results: 90 patients (56% men) aged 75 � 8 years were evaluated during a

mean follow-up of 15 � 5 months. Mean CHADS and CHADSVASc

scores were 2,3 � 1,0 and 4,0 � 1,3 respectively. Diabetes was present

in 28 patients (31%), structural heart disease in 31 patients (34%), heart

failure in 9 patients (10%), stroke in 10 patients (11%) and chronic kidney

disease in 22 patients (24%). AHRE were documented in 20 patients

(22%). Cranial CT-scan was performed in 59 patients (65,6%), it was

normal in 45 patients (76%) and it showed ischemic lesions in 14

(24%). Univariate analysis results are shown in the Table. Multivariate

analysis showed that CHADSVASc score (OR 1.90 [1.15 - 3.15; p

<0.05]) and the presence of AHRE (OR 6.82 [1.33 - 34.87; p <0.05])

were independent predictors of ischemic brain lesions.

Conclusions: Our data show that AHRE compatiblewith silent AF detected

by cardiac devices are really prevalent in high blood pressure patientswith no

history of previousAF (22%). The presence of these episodeswas associated

to a higher incidence of ischemic brain lesions on CT-scan. AHRE represent

a kind of silent AFwheremanagement recommendations are lacking despite

the fact that a higher embolic risk is present.

Keywords: Silent atrial fibrillation; ischemic brain lesions; cardiac

devices; atrial high rate episodes

P-254

Stroke burden remains high for blacks: an analysis of hospitalized

patients over twelve years

Baqar Husaini,1 Robert Levine,2 Muhib Khan,3 Majaz Moonis.3 1TennesseeState University, Nashville, TN, United States; 2Meharry Medical College,

Nashville, TN, United States; 3University of Massachusetts, Worcester,

MA, United States

Objective: Examine race variation in stroke burden and associated risk

factors over a period of twelve years among hospital discharged patients.

Method: We examined Tennessee Hospital Discharge Database from

1997-2008 for patients (aged 20+) discharged with a primary diagnosis

of stroke. Data on each patient was extracted for cardiovascular risk

factors. Age-adjusted prevalence rate of stroke per 100K for hospitalized

patients was developed per CDC methodology. Stroke rates as well as

associated risk factors for both white and black patients were examined

using multivariate logistic models. To examine consistency of differences

between white and black patients, we compared the two groups over

12 years at three different points, namely 1997, 2003, and 2008 regarding

the prevalence of stroke and associated risk factors.

Results: Analyses of 12-year data revealed three major trends: (i) Age-

adjusted stroke rate had declined by 13.8%, from 466.8 per 100K in

1997 to 402.2 per 100K in 2008. This decline (larger for whites than

blacks) occurred for both black and white patients; (ii) Durig 12 years,

the stroke rates among blacks remained higher compared to whites

(black-white rate ratios of 1.60 in 1997, 1.40 in 2003, and 1.60 in

2008); and (iii) logistic regressions pointed to four risk factors (hyperten-

sion, diabetes, high cholesterol, and cardiac arrhythmia) that predicted

stroke for both black and white patients in 1997, 2003, and 2008.

Conclusion: Stroke burden has remained high for the black population.

Aggressive management of two cardiovascular risk factors (Hypertension

and Diabetes) may subsequently reduce stroke health disparity and the

burden of stroke hospitalization among blacks.

Keywords: stroke rates; race; risk factors; racial disparity