Office and laboratory blood pressures as predictors of daily blood pressure level in normotensive subjects and borderline and mild hypertensive subjects

Abstract

A series of standardized laboratory tests [10 min sitting and supine, 9 min standing, dynamic; cycle ergometer (ERG) and isometric exercise; handgrip (HG)] were performed during intra-arterial blood pressure (BP) recording in 97 healthy unmedicated men, initially classified as normotensive (NT, n = 34), borderline hypertensive (BHT, n = 29) or mildly hypertensive (HT, n = 34) by repeated office blood pressure (OBP) measurements. After testing, a 24-h intra-arterial ambulatory BP (IABP) recording was obtained while subjects performed their normal activities. Day and night periods were analysed as well as 24-h averages for systolic BP (SBP) and diastolic BP (DBP) using Pearson correlations and multiple linear regressions. In normotensive subjects, the supine SBP predicted IABP measurements best (r range 0.39-0.69, P < 0.05-0.001). In multiple regression, supine SBP explained 49% of 24-h SBP variance (F = 12.4, P = 0.001). For BHT, supine SBP was also the best predictor (r range 0.09-0.64, P NS to P < 0.001), and it explained 37% of 24-h SBP variance (F = 15.6, P = 0.0005). In HT, ERG DBP correlated best with IABP (r range 0.52-0.75, P < 0.01-0.001). ERG SBP explained 49% of 24-h SBP (F = 31.0, P = 0.0000) and ERG DBP explained 56% of 24-h DBP (F = 35.4, P = 0.0000) variance. Laboratory BP correlations were generally better with day than with night measurements. OSBP correlated moderately well with IABP in NT, and weakly in BHT and HT; ODBP instead correlated with IABP in NT and HT but not significantly in BHT. In conclusion, OBP is less closely related to IABP than laboratory BP, but even laboratory BP generally explains less than 50% of IABP variance. Stressors such as exercise are useful only in HT. For BHT, the prediction of IABP with laboratory measures was even weaker than in other groups, and thus ambulatory measurements cannot be replaced by short-duration laboratory measurements and stress tests.

Hemodynamic profile, compensation deficit, and ambulatory blood pressure

“…Beta‐adrenergic activity increases as cognitive functioning become more complex (Streufert, DePadova, McGlynn, Pogash, & Piasecki, 1988), so that we can speculate that the mirror tracing task did not predict waking blood pressure because demands are less vascular in nature during waking hours. In line with Majahalme et al (1998), the isometric exercise (handgrip) did not prove to be a very useful predictor of ambulatory blood pressure level. Thus, the present data support the use of responses to cognitive rather than physical laboratory tasks as a potential marker of risk for hypertension (Kamarck & Lovallo, 2003; Schwartz et al, 2003).…”

“…Ambulatory blood pressure monitoring has become a commonly used method of assessing the generalizability of laboratory‐based cardiovascular reactivity to real‐life settings. Significant associations between reactivity and ambulatory blood pressure means have been reported in a number of studies (Cornish, Blanchard, & Jaccard, 1994; Light, Turner, Hinderliter, & Sherwood, 1993; Steptoe & Cropley, 2000), but others have only found weak correlations between these two measures (Fredrikson, Robson, & Ljungdell, 1991; Majahalme et al, 1998; Pickering & Gerin, 1988). Given that ambulatory 24‐h blood pressure is a highly established predictor of hypertensive target organ damage (Parati, Pomidossi, Albini, Malaspina, & Mancia, 1987), the current study investigated whether profiles formed on the basis of patterns of cardiac output and total peripheral resistance reactivity to laboratory tasks relate more closely to ambulatory blood pressure levels than blood pressure reactivity itself.…”