Orthostatic Hypotension Is a More Robust Predictor of Cardiovascular Events Than Nighttime Reverse Dipping in Elderly

Abstract

Abstract-Aims of the study were to assess in an elderly population the prevalences of orthostatic hypotension at different times after standing and of nighttime reverse dipping on ambulatory blood pressure monitoring, as well as their interrelationships and relative prognostic power for incident cardiovascular events. The study population consisted of 374 patients (225 women), aged 70.2Ϯ8.5 years, registered in 1 primary care practice and without major cardiovascular events or other comorbidities at baseline. They experienced 76 first cardiovascular events (death, myocardial infarction, or stroke) during 3406 years of follow-up. Systolic/diastolic orthostatic hypotension, defined as a decrease of systolic/diastolic blood pressure of Ն20/Ն10 mm Hg, was present in 24.0%/13.3% of the patients immediately after standing, and in, respectively, 18.1%/10.5% and 12.4%/11.6% after 1 and 2 minutes, whereas systolic/diastolic reverse dipping occurred in 14.4%/9.5%. Orthostatic hypotension was 2 to 3 times more prevalent in reverse dippers than in dippers (PՅ0.01). Systolic orthostatic hypotension was a significant and independent predictor of cardiovascular events, which was stronger during recovery than immediately after standing; in Cox regression analysis, the adjusted hazard ratio amounted to 2.38 (PϽ0.01) after 2 minutes. The independent predictive power of diastolic orthostatic hypotension was only significant soon after standing (PϽ0.05). Systolic and diastolic reverse dipping carried prognostic significance in univariable analyses (PϽ0.001) but not after adjustment for confounders, including 24-hour blood pressure. We conclude that orthostatic hypotension contributes to the phenomenon of reverse dipping but is a more robust predictor of cardiovascular events than reverse dipping in the elderly of the current study. (Hypertension. 2010;56:56-61.)Key Words: ambulatory blood pressure monitoring Ⅲ cardiovascular events Ⅲ orthostatic hypotension Ⅲ prevalence Ⅲ prognosis Ⅲ reverse dipping A number of studies have assessed the prognostic significance of orthostatic hypotension (OH) 1-12 or reverse dipping on ambulatory blood pressure (BP; ABP) monitoring (ABPM). [13][14][15][16][17][18][19] Daytime ABP is usually higher than nighttime ABP, and the reverse diurnal pattern is independently associated with a higher incidence of cardiovascular events 16,18,19 and mortality 13,15,16,18,19 in most but not all studies. 14,17 Also, OH carries a worse prognosis for all-cause 4,9,11,12 and cardiovascular mortality, 5,9 coronary heart disease (CHD), 7,8,11,12 stroke, 6 or an aggregate of cardiovascular events, 12 although not all of the studies agree with regard to mortality 1-3,10 or stroke. 11,12 OH has been defined as a reduction of systolic BP of Ն20 mm Hg or of diastolic BP of Ն10 mm Hg within 3 minutes of standing, 20 but this definition has been applied differently in the various prognostic studies. Some authors have reported on single BP measurements at different time intervals after standing, [2][3][4][5]8,12 whereas others...

Treatment of Hypertension in the Oldest Old

“…[40][41][42] However, in a recent analysis, this association was no longer significant after adjustment for frailty, suggesting that the latter is more important for survival. 43 …”

“…79 However, the association of orthostatic hypotension with risk of cardiovascular events was mainly because of the delayed orthostatic BP drop. 42 In conclusion, the bulk of the evidence suggests that, overall, increasing systolic and diastolic BP is associated with increasing cardiovascular risk and mortality. The picture is far less clear, however, in older individuals who are frail, as indicated, for example, by walking speed or comorbidity.…”

Hipotensão Ortostática E O Risco De Doenças Cardiovasculares Em Idosos: Uma Revisão De Literatura

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“…A study of ambulatory BP monitoring showed that an abnormal diurnal BP of decline of average BP by ≥20% during sleep ("extreme dipping") or rise in nocturnal BP ("reverse dipper") are associated with new occurrence of silent and clinical cerebral ischemia [9]. Orthostatic hypotension is also associated with higher stroke risk [10]. Secondary analyses of a comparative trial of BP regimen suggests that the differences in visit-to-visit variability among the drug regimen accounts for the differences in cardiovascular events better than mean BP differences alone [11].…”