Background: Morning blood pressure (BP) peak may be a risk factor for cardiovascular disease. Whether morning BP should be a target of hypertension treatment is not known. We investigated the relationship between morning BP variations, carotid internal-medial thickness (CIMT), circulating inflammatory markers, and sympathetic activity in hypertensive patients with different patterns of morning BP increase at baseline and after antihypertensive treatment.
Methods: One hundred twenty-eight hypertensive patients with morning BP peak (MP+) were compared with 196 hypertensive patients without morning BP peak (MP-). All patients performed 24-h ambulatory BP monitoring, assessment of CIMT, circulating concentration of C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-18 (IL-18), and urinary catecholamines.
Results: Compared with MP- patients, MP+ patients had higher CIMT and urinary catecholamine output (P < .001), as well as CRP, IL-6, and IL-18 (P < .001). We randomly assigned 128 drug-naive MP+ patients to either metoprolol or carvedilol, two antihypertensive drugs with different effects on sympathetic activity. The primary outcome was change in CIMT and circulating inflammatory markers at 12 months. Morning BP decreased more among patients in the carvedilol group (P < .001), whereas clinic BP showed a similar decrease in both groups. The CIMT (P < .001), IL-6 (P < .001), IL-18 (P < .001), and CRP (P < .001) decreased more in the carvedilol group than in the metoprolol group. The CIMT regression was observed in 49% of patients in the carvedilol group and 18% of patients in the metoprolol group (P < .01). Reduction in CIMT was directly associated with changes in morning BP.
Conclusions: Higher CIMT and circulating inflammatory markers coexist in hypertensive patients with morning BP peak, and might contribute to their increased cardiovascular risk. Carotid atherosclerosis can be prevented by control of morning BP.