Estudios en hipertension

Hypertension Research (2012) 00, 1–9 & 2012 The Japanese Society of Hypertension All rights reserved 0916-9636/12
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ORIGINAL ARTICLE

Relationship between achieved blood pressure, dietary habits and cardiovascular disease in hypertensive patients treated with olmesartan: the OMEGA study
Tamio Teramoto1, Ryuzo Kawamori2, Shigeru Miyazaki3, Satoshi Teramukai4, MasayukiShirayama5, Katsutoshi Hiramatsu5, Fumiaki Kobayashi5 and the OMEGA Study Group6
We investigated the relationship between cardiovascular disease (CVD) and the achieved blood pressure, dietary habits and the presence/absence of metabolic syndrome (MetS) in hypertensive patients treated with olmesartan medoxomil. A prospective cohort study with a 3-year follow-up was conducted in 14 721 olmesartan-naiveoutpatients (mean age: 64.9 years, 49.6% women) with essential hypertension. The association of CVD with achieved blood pressure, dietary habits and MetS was investigated by Cox proportional hazards analysis. There were 3059 patients (31.8%) with MetS (Japanese criteria) among 9625 evaluable patients. The mean baseline blood pressure was 157.4/88.8 mm Hg, which decreased to 134.0/76.1 mm Hg duringtreatment (Po0.0001). The annual incidence of CVD was 7.15 per 1000 persons during the study period. When the achieved blood pressure was stratified according to the Japanese Society of Hypertension Guidelines for the Management of Hypertension (JSH 2009), the risk of CVD increased significantly along with the severity of hypertension (Po0.0001), especially the risk of stroke. Investigation ofdietary habits revealed a significant association between salt intake and the risk of stroke. Higher salt intake was associated with a significantly higher risk of stroke than lower salt intake (hazard ratio, 1.897; 95% confidence interval, 1.003–3.590). Blood pressure was well controlled in both patients with and without MetS, and there was no significant difference in the incidence of events between thetwo groups. In conclusion, the severity of hypertension (achieved blood pressure) is associated with the incidence of CVD, and the results of this study suggest that tight blood pressure control and salt restriction are important for preventing stroke. Hypertension Research advance online publication, 5 July 2012; doi:10.1038/hr.2012.93 Keywords: cardiovascular disease; metabolic syndrome;olmesartan; salt intake; stroke

INTRODUCTION Hypertension is known to be one of the main risk factors for cardiovascular disease (CVD).1,2 A number of large-scale studies on the relationship between hypertension and CVD have indicated that strict blood pressure control is important for preventing CVD.3,4 Accumulation of risk factors is related to the morbidity and mortality of CVD, so metabolicsyndrome (MetS) has been attracting more attention in this context over the past decade. Diagnostic criteria for this syndrome have been published overseas,5,6 and also eight Japanese academic societies have jointly published diagnostic criteria for MetS in 2005.7 Several reports regarding the relationship between MetS and CVD in hypertensive patients have been published overseas.8–10 In Japan, theHisayama study11 and the Tanno and Sobetsu study12 have provided evidence that MetS is a significant risk factor for CVD in the general population. However, no large-scale

studies have been conducted in Japan to assess the risk factors for CVD in hypertensive patients who also have MetS. The INTERSALT study13 and other studies have shown that excessive salt intake is related to high blood pressure,whereas the DASH-Sodium study14 and other large-scale studies have suggested that reducing the intake of salt is effective for lowering the blood pressure. Increased potassium intake has also been recommended for reducing the blood pressure, but there is no supportive epidemiological evidence available. Furthermore, it has been reported that intake of soy protein and omega-3 unsaturated fatty...