Increased nighttime blood pressure or nondipping profile for prediction of cardiovascular outcomes
C Tsioufis1, I Andrikou1, C Thomopoulos1, D Syrseloudis1, G Stergiou2 and C Stefanadis1
First Cardiology Clinic, Hippokration Hospital,University of Athens, Athens, Greece and 2Third Department of Medicine, Hypertension Center, Sotiria Hospital, Athens, Greece
At present, clinic blood pressure (BP) evaluation is being increasingly complemented by ambulatory BP measurements for the evaluation of haemodynamic patterns during daily activities and sleep. Nondipping pattern, a measure of decreased attenuation of nighttime over daytimeBP, has been correlated with enhanced target organ damage and adverse cardiovascular (CV) outcomes in different clinical settings beyond pure hypertensive cohorts. As the nondipping pattern is a derivative extract of both daytime and nighttime BP, it is yet questionable whether the crude estimate of nocturnal BP is superior to daytime BP and
nondipping pattern in the prediction of subclinicaldamage and CV events. In this review, we aimed at comparing the CV predictive value of the nondipping pattern with that of nocturnal BP using cross-sectional and longitudinal data obtained from different cohort studies within the past 10 years. Our findings suggest that nocturnal BP including the phenotype of isolated nocturnal hypertension is better associated with CV target organ damage and‘hard end points’ as compared with the nondipping pattern. Journal of Human Hypertension (2011) 25, 281–293; doi:10.1038/jhh.2010.113; published online 2 December 2010
Keywords: nocturnal blood pressure; dipping profile; chronotherapy; circadian blood pressure variability
Ambulatory blood pressure (BP) monitoring (ABPM) is a widely used tool in hypertension management,1 andcompared with isolated office BP, it provides first, a more accurate estimation of the overall cardiovascular (CV) risk burden and second, demonstrates higher reproducibility in the prediction of target organ damage and adverse CV outcomes.2 Along with 24-h systolic and diastolic BP, both reflecting the cardinal clinical components of the haemodynamic load magnitude, the prognostic impact of diversetime-dependent ABPM components (namely daytime and nighttime BP) and circadian BP variability patterns (such as dipping status, nightto-day BP ratio, early morning surge) have been previously investigated.3 Although both averaged nocturnal BP values4–6 and blunted nocturnal decrease with respect to daytime BP7–9 were found to be associated with subclinical target organ damage and to heighten CVmorbidity and mortality, their relative importance is still controversial.
Correspondence: Dr C Tsioufis, First Cardiology Clinic, Hippokration Hospital, University of Athens, Athens, Greece. E-mail: email@example.com Received 15 September 2010; revised 1 November 2010; accepted 5 November 2010; published online 2 December 2010
In this review, we aimed at addressing whether eitheraveraged nocturnal BP or estimates of nighttime-focused circadian BP variability, namely dipping and nondipping patterns, are better associated with intermediate (that is, target organ damage) and hard CV outcomes (that is, CV morbidity and mortality), acknowledging that these ABPM-derived clinical qualifications may coexist. In this perspective, we reviewed 144 clinical studies conducted between 2000and 2009 identified in the PubMed and Cochrane Database by implementing the search terms: ‘nocturnal hypertension’, ‘nocturnal BP’, ‘nighttime BP’, ‘dipping pattern’, ‘nondipping pattern’, ‘BP nondipping’, ‘BP dipping’ and each one of the aforementioned quoted phrases plus ‘cardiovascular disease’, ‘cardiovascular morbidity/mortality’, ‘all-cause mortality’, ‘cardiovascular risk’, ‘myocardial...