CIENCIASMEDICASNEWS: Blood Pressure Circadian Pattern and Physical Exercise Assessment by Accelerometer and 7-Day Physical Activity Recall Scale

lunes, 16 de septiembre de 2013

Blood Pressure Circadian Pattern and Physical Exercise Assessment by Accelerometer and 7-Day Physical Activity Recall Scale

+ Author Affiliations

¹ Alamedilla Health Center, Castilla y León Health Service (SACYL), Instituto de Investigación Biosanitario de Salamanca (IBSAL), Salamanca, Spain;

² School of Education, Physical Activity and Sport Science, Department of Social Sciences, University of Vic, Barcelona, Spain;

³ Cuenca III Health Center, Castilla la Mancha Health Service (SESCAM), Cuenca, Spain;

⁴ Casa de Barco Health Center, Castilla y León Health Service (SACYL), Valladolid, Spain;

⁵ Torre Ramona Health Center, Aragón Health Service–Salud, Zaragoza, Spain;

⁶ Primary Care Research Unit of Bizkaia, Basque Health Service-Osakidetza, Bilbao, Spain;

⁷ EVIDENT Group: Red de Investigación en Actividades Preventivas y Promoción de la Salud (Research Network on Preventive Activities and Health Promotion), Spain

Correspondence: Luis García Ortiz (Lgarciao@usal.es).

Received May 11, 2013.

Revision received July 10, 2013.

Accepted July 26, 2013.

Abstract

BACKGROUND The relationship between regular physical activity, measured objectively and by self-report, and the circadian pattern of 24-hour ambulatory arterial blood pressure (BP) has not been clarified.

METHODS We performed a cross-sectional study in a cohort of healthy patients. We included 1,345 patients from the EVIDENT study (mean age 55±14 years; 59.3% women). Physical activity was assessed using the 7-day physical activity recall (PAR) questionnaire (metabolic equivalents (MET)/hour/week) and the Actigraph GT3X accelerometer (counts/minute) for 7 days; ambulatory arterial BP was measured with a radial tonometer (B-pro device).

RESULTS The dipper-pattern patients showed a higher level of activity than nondipper patients, as assessed by accelerometer and 7-day PAR. Physical activity measures correlated positively with the percent drop in systolic BP (SBP; ρ = 0.19 to 0.11; P < 0.01) and negatively with the systolic and diastolic sleep to wake ratios (ρ = −0.10 to −0.18; P < 0.01) and heart rate (ρ = −0.13; P < 0.01). In logistic regression, considering the circadian pattern (1, dipper; 0, nondipper) as the dependent variable, the odds ratio of the third tertile of counts/minute was 1.79 (95% confidence interval [CI], 1.35–2.38; P < 0.01) and of MET/hour/week was 1.33 (95% CI, 1.01–1.75; P = 0.04) after adjustment for confounding variables.

CONCLUSIONS Physical activity, as evaluated by both the accelerometer and the 7-day PAR, was associated with a more marked nocturnal BP dip and, accordingly, a lower SBP and diastolic BP sleep to wake ratio.

CLINICAL TRIAL REGISTRATION Clinical Trials.gov Identifier: NCT01083082