Race and sex differences in asleep blood pressure: The Coronary Artery Risk Development in Young Adults (CARDIA) study

Abstract

Nocturnal hypertension and non-dipping blood pressure are each associated with increased risk of cardiovascular disease. We determined differences in nocturnal hypertension and non-dipping systolic/diastolic blood pressure among black and white men and women who underwent 24-hour ambulatory blood pressure monitoring at the Coronary Artery Risk Development in Young Adults study Year 30 Exam in 2015–2016. Asleep and awake periods were determined from actigraphy complemented by sleep diaries. Nocturnal hypertension was defined as mean asleep systolic/diastolic blood pressure ≥ 120/70 mm Hg. Non-dipping systolic and diastolic blood pressure, separately, were defined as a decline in awake-to-asleep blood pressure < 10%. Among 767 participants, the prevalence of nocturnal hypertension was 18.4% and 44.4% in white and black women, respectively, and 36.4% and 59.9% in white and black men, respectively. After multivariable adjustment and compared with white women, the prevalence ratio (95% confidence interval) for nocturnal hypertension was 1.65 (1.18–2.32) for black women, 1.63 (1.14–2.33) for white men, and 2.01 (1.43–2.82) for black men. The prevalence of non-dipping systolic blood pressure was 21.5% and 41.0% in white and black women, respectively, and 20.2% and 37.9% in white and black men, respectively. Compared with white women, the multivariable-adjusted prevalence ratio (95% confidence interval) for non-dipping systolic blood pressure was 1.66 (1.18–2.32), 0.91 (0.58–1.42) and 1.66 (1.15–2.39) among black women, white men, and black men, respectively. Non-dipping diastolic blood pressure did not differ by race-sex groups following multivariable adjustment. In conclusion, black women and men have a high prevalence of nocturnal hypertension and non-dipping systolic blood pressure.

Prognostic value of nondipping: Are there ethnic differences?

“…However, it cannot be excluded that differences may also be related to other factors, such as ethnicity. It has been reported that prevalence of nondippers may be different according to ethnicity 5 . At present, we do not know whether the prognostic value of nondipping may be different in various ethnic groups.…”

“…It has been reported that prevalence of nondippers may be different according to ethnicity. 5 At present, we do not know whether the prognostic value of nondipping may be different in various ethnic groups. Future studies with similar recruitment criteria, methodological aspects, cardiovascular end points, statistical approach and of adequate power should be performed to investigate potential differences among ethnic groups.…”

Associations Between Objective Sleep and Ambulatory Blood Pressure in a Community Sample

“…In addition to nighttime BP, we sought to examine the more specific concept of "asleep blood pressure". Similar to the International Database of Ambulatory Blood Pressure in relation to Cardiovascular Outcomes (IDACO) and methods employed in The Coronary Artery Risk Development in Young Adults (CARDIA) study (52) and in consultation with sleep and ambulatory BP experts, we operationalized asleep BP as BP readings occurring during a period of time that included at least 90% actigraphic sleep. For those whom less than 90% sleep occurred in the 12-5am window, but who had significant sleep period overlapping with some part of the 12-5am window, we identified the actigraphic parameters of their sleep window not to exceed the 5 hours total and averaged BP from within that window to represent "sleep BP."…”

Echocardiography Segmentation by Fractional Differential and Improved Canny, Analysis by Fourier Descriptor

“…The main weakness of the detection is that the incidence angle of the ultrasound is not consistent with the direction of the movement, so obtained velocity error is great. The Anatomic M-mode (AMM) echocardiography is for post-processing an original image to obtain a motion curve of the interested local myocardium in wall or with the slice captured through the location of a sample line in the image [5][6] . The AMM echocardiography can only be set with three sampling lines in an image, but it cannot get the curves of the myocardial motion of the walls during the same cardiac cycle.…”