Chronobiology international
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Randomized Controlled Trial
Ambulatory blood pressure thresholds for diagnosis of hypertension in patients with and without type 2 diabetes based on cardiovascular outcomes.
Currently recommended ambulatory blood pressure (BP) monitoring (ABPM) thresholds for diagnosis of hypertension do not differentiate, as international guidelines do for clinic BP, uncomplicated persons at low risk from those at higher risk, e.g., patients with diabetes, for target injury and cardiovascular disease (CVD) risk. We aimed to derive diagnostic thresholds for the awake and asleep systolic (SBP) and diastolic (DBP) BP means based upon CVD outcomes (death from all causes, myocardial infarction, angina pectoris, coronary revascularization, heart failure, acute arterial occlusion of the lower extremities, thrombotic occlusion of the retinal artery, hemorrhagic stroke, ischemic stroke, and transient ischemic attack) for patients with and without diabetes. We prospectively studied 3344 subjects (1718 men/1626 women), 52.6 ± 14.5 (mean ± SD) yrs of age, 607 with type 2 diabetes, during a median follow-up of 5.6 yrs. ⋯ In terms of CVD outcome, the equivalent cutoff threshold values for patients with diabetes were 120/75 mm Hg for the awake and 105/60 mm Hg for the asleep SBP/DBP means. Outcome-based reference thresholds for the diagnosis of hypertension were 15/10 mm Hg lower for ambulatory SBP/DBP in patients with than without diabetes. This marked difference indicates the need for revision of current guidelines that propose diagnostic thresholds for ambulatory BP without differentiation between the presence/absence of diabetes.
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Randomized Controlled Trial Multicenter Study
Prevalence and clinical characteristics of isolated-office and true resistant hypertension determined by ambulatory blood pressure monitoring.
Hypertension is defined as resistant to treatment when a therapeutic plan including ≥3 hypertension medications failed to sufficiently lower systolic (SBP) and diastolic (DBP) blood pressures (BPs). Most individuals, including those under hypertension therapy, show a "white-coat" effect that could cause an overestimation of their real BP. The prevalence and clinical characteristics of "white-coat" or isolated-office resistant hypertension (RH) has always been evaluated by comparing clinic BP values with either daytime home BP measurements or the awake BP mean obtained from ambulatory monitoring (ABPM), therefore including patients with either normal or elevated asleep BP mean. ⋯ Previous reports of much lower prevalence of true RH plus a nonsignificant increased CVD risk of this condition compared with isolated-office RH are misleading by disregarding asleep BP mean for classification. Our results further indicate that classification of RH patients into categories of isolated-office RH, masked RH, and true RH cannot be based on the comparison of clinic BP with either daytime home BP measurements or awake BP mean from ABPM, as so far customary in the available literature, totally disregarding the highly significant prognostic value of nighttime BP. Accordingly, ABPM should be regarded as a clinical requirement for proper diagnosis of true RH.
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Randomized Controlled Trial
Blunted sleep-time relative blood pressure decline increases cardiovascular risk independent of blood pressure level--the "normotensive non-dipper" paradox.
Numerous studies have consistently shown an association between blunted sleep-time relative blood pressure (BP) decline (non-dipping) and increased cardiovascular disease (CVD) risk in hypertension. Normotensive persons with a non-dipper BP profile also have increased target organ damage, namely, increased left ventricular mass and relative wall thickness, reduced myocardial diastolic function, increased urinary albumin excretion, increased prevalence of diabetic retinopathy, and impaired glucose tolerance. It remains a point of contention, however, whether the non-dipper BP pattern or just elevated BP, alone, is the most important predictor of advanced target organ damage and future CVD events. ⋯ Our findings document that the risk of CVD events is influenced not only by ambulatory BP elevation, but also by blunted nighttime BP decline, even within the normotensive range, thus supporting ABPM as a requirement for proper CVD risk assessment in the general population. The elevated CVD risk in "normotensive" individuals with a non-dipper BP profile represents a clear paradox, as those persons do not have "normal BP" or low CVD risk. Our findings also indicate the need to redefine the concepts of normotension/hypertension, so far established on the unique basis of BP level, mainly if not exclusively measured at the clinic, independently of circadian BP pattern.
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Randomized Controlled Trial Multicenter Study
Treatment-time regimen of hypertension medications significantly affects ambulatory blood pressure and clinical characteristics of patients with resistant hypertension.
Patients with resistant hypertension (RH) are at greater risk for stroke, renal insufficiency, and cardiovascular disease (CVD) events than are those for whom blood pressure (BP) is responsive to and well controlled by therapeutic interventions. Although all chronotherapy trials have compared the effects on BP regulation of full daily doses of medications when ingested in the morning versus at bedtime, prescription of the same medications in divided doses twice daily (BID) is frequent. Here, we investigated the influence of hypertension treatment-time regimen on the circadian BP pattern, degree of BP control, and relevant clinical and laboratory medicine parameters of RH patients evaluated by 48-h ambulatory BP monitoring (ABPM). ⋯ Our findings demonstrate significantly lower asleep SBP and DBP means and attenuated prevalence of blunted nighttime BP decline, i.e., lower prevalence of CVD risk markers, in RH patients ingesting the full daily dose of ≥1 hypertension medications at bedtime than in those ingesting all of them upon awakening or ≥1 of them as split doses BID. In RH, ingesting the same medications BID neither improves ambulatory BP control nor reduces the prevalence of non-dipping, and cannot be considered chronotherapy. Collectively, findings of this study indicate that a bedtime hypertension medication regimen, in conjunction with proper patient evaluation by ABPM to corroborate the diagnosis of true RH and avoid treatment-induced nocturnal hypotension, should be the therapeutic scheme of choice for patients who, by conventional cuff methods (and in the absence of ABPM) and the morning-treatment regimen, have been mistakenly judged to be resistant to therapy.
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Randomized Controlled Trial
Cardiovascular risk of essential hypertension: influence of class, number, and treatment-time regimen of hypertension medications.
A number of observational studies have found that treated hypertensive patients, even those with controlled clinic blood pressure (BP), might have poorer prognosis than untreated hypertensives. Different trials have also shown that relatively low cardiovascular disease (CVD) risk cannot be achieved in high-risk hypertensive patients, leading to the belief they have a "residual CVD risk" that cannot be attenuated by conventional treatment. All these conclusions disregard the facts that the correlation between BP level and CVD risk is stronger for ambulatory than clinic BP and that the BP-lowering efficacy and effects on the 24-h BP pattern of different classes of hypertension medications exhibit statistically and clinically significant treatment-time (morning versus evening) differences. ⋯ Among patients randomized to ingest ≥1 medications at bedtime, however, ARBs were associated with significantly lower HR of CVD events than ingestion of any other class of medication also at bedtime (p < .017). We document significantly reduced CVD risk among hypertensive patients ingesting medications at bedtime, independent of the number of hypertension medications required to achieve proper ambulatory BP control. These findings challenge the current belief of "residual CVD risk," as a bedtime-treatment regimen of current hypertension medications, even in risk-high patients, can reduce such risk.