Cerebral perfusion in the elderly with nocturnal blood pressure fall

Abstract

Cerebrovascular disease may be linked with vascular autoregulation in aging. The aim of this study was to examine relation between nocturnal blood pressure (BP) fall and cerebral blood flow (CBF) changes in elderly men. The prospective 'Men born in 1914' cohort study has been in progress since 1968 and included 809 subjects. After 14 years from the last follow up, 97 subjects reached the age of 82 and underwent CBF measurement and 24 h ambulatory blood pressure monitoring. Diastolic BP at night decreased in 84 subjects with median 12.7% and increased in 13 subjects with median 3.7%. Relative diastolic BP fall at night was negatively associated to CBF in temporal and infero-parietal areas. Higher proportion of subjects with increasing systolic BP during the 14-year period was observed in the subgroup with extreme nocturnal diastolic BP dip, irrespectively of BP values or prevalence of hypertension. Extreme nocturnal diastolic BP fall in a cohort of elderly men is correlated with focal changes in CBF. Further studies could explain if increasing BP in the elderly is a cause or result of pathological autoregulation, and if antihypertensive treatment increases nocturnal BP dip.

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

“…14 Finally, in a small number of octogenarians, stroke incidence was not different according to the dipping pattern. 17 We observed that reverse dipping was strongly associated with future cardiovascular events in univariable Cox regression analysis, but this relationship was no longer significant after full adjustment. Age, male sex, and 24-hour BP were the stronger predictors in the multivariable models.…”

“…[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][2][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.…”

Nocturnal blood pressure and cardiovascular disease: a review of recent advances

“…27,31,[33][34][35] Extreme dipping is a complex phenomenon. Contrary to the established notion that subjects with low nocturnal BP are at low cardiovascular risk, extreme dippers have a higher prevalence of silent cerebral infarction, deep white matter lesions and silent myocardial ischemia during sleep than dippers.…”

“…Contrary to the established notion that subjects with low nocturnal BP are at low cardiovascular risk, extreme dippers have a higher prevalence of silent cerebral infarction, deep white matter lesions and silent myocardial ischemia during sleep than dippers. 27,33,34,36,37 Nocturnal hypoperfusion at the brain and/or heart during extreme dipping may occur, leading to organ damage. This is particularly of concern in older hypertensive patients with impaired cerebral autoregulation.…”

Cerebrovascular reactivity and dynamic autoregulation in ischaemic subcortical white matter disease

“…Recent studies have emphasised the importance of physiological variations in BP in the prediction of cerebral blood flow (CBF) and cerebrovascular disease, particularly with reference to nocturnal BP fall 13 14. The integrity of cerebral vasoreactivity and autoregulation is crucial in maintaining a constant CBF in the face of such BP fluctuations.…”