The influence of body composition and fat distribution on circadian blood pressure rhythm and nocturnal mean arterial pressure dipping in patients with obesity

Abstract

Loss of physiological nocturnal blood pressure (BP) decline is an independent predictor of cardiovascular risk and mortality. The aim of the study was to investigate the influence of body composition and fat distribution on 24-hour BP pattern and nocturnal dipping of mean arterial pressure (MAP) in patients with obesity. The study comprised 436 patients, 18 to 65 years old (306 women), with BMI ≥30 kg/m2. Body composition was assessed with dual-energy X-ray absorptiometry (DXA) and blood pressure was assessed by 24-hour BP monitoring. The prevalence of hypertension was 64.5% in patients with BMI <40 kg/m2 and increased to 78.7% in individuals with BMI ≥50 kg/m2 (p = 0.034). The whole-body DXA scans showed that the hypertensive patients were characterized by a greater lean body mass (LBM) and a higher abdominal-fat-to-total-fat-mass ratio (AbdF/FM), while the normotensive participants had greater fat mass, higher body fat percentage and more peripheral fat. Loss of physiological nocturnal MAP decline was diagnosed in 50.2% of the patients. The percentage of non-dippers increased significantly: from 38.2% in patients with BMI <40 kg/m2 to 50.3% in those with BMI 40.0–44.9 kg/m2, 59.0% in patients with BMI 45.0–49.9 kg/m2, 71.4% in those with BMI 50.0–54.9 kg/m2 and 83.3% in patients with BMI ≥55 kg/m2 (p = 0.032, p = 0.003, p<0.001, and p = 0.002 vs. BMI <40 kg/m2, respectively). The multivariable regression analysis showed that patients at the highest quartiles of body weight, BMI, LBM and AbdF/FM had significantly reduced nocturnal MAP dipping compared with patients at the lowest quartiles, respectively.

Update on chronotherapy: it's about time

“…“The classic example of chronotherapy is treating nocturnal asthma with delayed‐release formulations of theophylline,” Dr Dallmann says. “Similarly, we should consider the timing of signs and symptoms when prescribing for arthritis and hypertension.” 14‐16 …”

“…In healthy people, blood pressure reaches a nadir at about midnight 15 . Blood pressure rises rapidly before we wake in the morning in anticipation of our rising to face the day.…”

“…Blood pressure rises rapidly before we wake in the morning in anticipation of our rising to face the day. People without the healthy overnight blood pressure dip of 10% to 20% are, for instance, more likely to develop and die from cardiovascular disease or develop hypertensive complications, such as renal or eye disease 15 . Some cardiovascular risk factors, such as hypertension, can blunt the decline, while taking antihypertensives at night can normalise nocturnal dipping 15,16 …”

“…"Similarly, we should consider the timing of signs and symptoms when prescribing for arthritis and hypertension." [14][15][16] In healthy people, blood pressure reaches a nadir at about midnight. 15 Blood pressure rises rapidly before we wake in the morning in anticipation of our rising to face the day.…”

“…[14][15][16] In healthy people, blood pressure reaches a nadir at about midnight. 15 Blood pressure rises rapidly before we wake in the morning in anticipation of our rising to face the day. People without the healthy overnight blood pressure dip of 10% to 20% are, for instance, more likely to develop and die from cardiovascular disease or develop hypertensive complications, such as renal or eye disease.…”