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Diastolic Dysfunction Tied to Impaired Exercise Capacity in Older Men With HIV
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IWCADR: Hypertension Increased in HIV+ vs HIV-neg in Amsterdam AgehIV Cohort Study (45% vs 31%) & HIV is Independently Associated with Hypertension - (10/17/14)
IWCADR: Impaired Cardiac Strain and Biomarkers of Immune Activation in HIV - (10/08/14)
Understanding Blood Pressure Readings
http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/AboutHighBloodPressure/Understanding-Blood-Pressure-Readings_UCM_301764_Article.jsp.......it should normally be less than 120/80 mm Hg (less than 120 systolic AND less than 80 diastolic) for an adult age 20 or over. About one in three U.S. adults has high blood pressure.
5th International Workshop on HIV and Aging. October 21-22, 2014. Baltimore.
Mark Mascolini
Impaired diastolic function predicted decreased aerobic capacity in older US veterans with HIV, according to results of a 101-man cross-sectional study [1]. None of the men in this Veterans Aging Cohort Study (VACS) group had a history or symptoms of coronary heart disease.
Diastolic dysfunction is an abnormality in the heartbeat phase in which the heart fills with blood [2]. It can impair oxygenation of blood in the lungs and cause shortness of breath and death. VACS investigators who conducted this study noted that HIV-positive adults run a greater risk of diastolic dysfunction and low aerobic exercise capacity and that diastolic function has been linked to aerobic capacity in HIV-negative adults. Previous work by these investigators found hypertension to be independently associated with low aerobic capacity.
They noted that about 28% of US adults over 45 have diastolic dysfunction.
This cross-sectional study involved HIV-positive veterans enrolled in the VACS CVD study at the Baltimore VA site. To measure aerobic capacity, health workers recorded gas exchange at peak exercise (VO2peak) during treadmill testing. They used Doppler echocardiography to record early diastolic (E) and atrial (A) mitral inflow velocities, as well as mitral annular longitudinal diastolic velocity (e'). They defined uncontrolled hypertension as resting systolic blood pressure above 140 mm Hg.
The 101 men with treadmill data averaged 54.5 years in age (+/- 6.5) and 95 (94%) were African American. Median CD4 count of the study group stood at 428, and 72% had a viral load below 400 copies. Median body mass index measured 25 kg/m2 (range 17 to 40). More than half of the men (59%) had hypertension, and most were current smokers (72%) or former smokers (12%).
VO2peak averaged 27.0 (+/-5.7) mL/kg/min in the study group. Nine veterans with uncontrolled hypertension had significantly lower VO2peak than the whole group: 21.9 (+/- 1.8) mL/kg/min (P < 0.01).
VO2peak correlated positively with myocardial relaxation (e', r = 0.30, P < 0.01), positively with left ventricular chamber relaxation (E/A ratio, r = 0.30, P < 0.01), and inversely with left ventricular end diastolic pressure (E/e', r = -0.22, P = 0.045). The association of VO2peak with e' and E/A ratio remained significant (P < 0.04) in linear regression models adjusted for age, race, and uncontrolled hypertension.
The VACS team concluded that "diastolic function is independently associated with aerobic exercise capacity in older HIV-infected men without [a] history or symptoms of coronary heart disease." They noted that diastolic function is easy to measure and detectable early, so early intervention may be possible. They believe their findings underline the importance of "managing clinical factors associated with diastolic dysfunction in HIV-infected" people. The VA team called for further research to determine (1) whether pathophysiologic mechanisms for this finding differ by HIV status and age and (2) whether exercise training can improve diastolic function and aerobic capacity in affected individuals.
References
1. McClintic H, Gottdiener J, Crothers K, et al. Diastolic function predicts impaired exercise capacity in older HIV-infected men. 5th International Workshop on HIV and Aging. October 21-22, 2014. Baltimore. Abstract 3.
2. Mandal A. What is diastolic dysfunction. News-Medical.net. http://www.news-medical.net/health/What-is-Diastolic-Dysfunction.aspx
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