Hypertension Unit, 1st Cardiology Clinic, Athens University, Hippokration, Hospital, Athens, Greece.
Hypertens Res. 2011 Feb;34(2):253-6. doi: 10.1038/hr.2010.226. Epub 2010 Dec 2.
β-thalassemia trait (β-TT) is a common genetic disorder in Mediterranean countries, including Greece. Previous studies have shown the protective effect of β-TT against myocardial infarction. However, the ambulatory blood pressure (BP) profile of such patients has not yet been investigated. Thus, the purpose of the present study was to investigate the ambulatory BP monitoring (ABPM) profile of hypertensives with β-TT, in comparison with all-cause anemic and non-anemic essential hypertensive patients. The study ultimately comprised of 8861 essential hypertensive, nondiabetic patients who were divided into three groups: group I (n=191, with β-TT), group II (n=655, anemic) and group III (n=8015, nonanemic). All patients underwent full clinical, laboratory and echocardiographic evaluations, whereas all were subjected to ABPM. Anemia was defined as Hb <12 g per 100 ml for women and <13 g per 100 ml for men, whereas patients with β-TT were self-referred. The distribution of dipping patterns among the three groups was 61.3 vs. 41.2 vs. 45.8% (P<0.001), whereas for nondippers it was 20.4 vs. 31.5 vs. 27.7% (P<0.001), for extreme-dippers it was 15.7 vs. 15.0 vs. 17.5% (P<0.001) and for reverse dippers it was 2.6 vs. 12.4 vs. 9.0% (P<0.001). Furthermore, mean daytime systolic BP (SBP) among the three groups was 140.13 ± 7.79 vs. 142.02 ± 11.61 vs. 141.99 ± 9.87 mm Hg (P=0.03), and mean nighttime SBP was 125.87 ± 10.4 vs. 131.13 ± 15.7 vs. 129.62 ± 13.31 mm Hg (P<0.001). In the multiple regression analysis, after adjustments for age, body mass index and lipid levels, the differences among daytime and nighttime SBP remained significant at 140.18 ± 9.84 vs. 142.02 ± 9.85 vs. 141.99 ± 9.85 mm Hg (P=0.04) and 125.99 ± 13.07 vs. 131.19 ± 13.08 vs. 129.61 ± 13.07 mm Hg (P<0.001), respectively. Hypertensive patients with β-TT present with a better 24-h BP profile in comparison with anemic and nonanemic hypertensives. Thus, β-TT may function protectively in their total cardiovascular risk profile.
β-地中海贫血（β-TT）是地中海国家（包括希腊）常见的遗传疾病。先前的研究表明，β-TT 对心肌梗死具有保护作用。然而，此类患者的动态血压（ABPM）特征尚未得到研究。因此，本研究旨在比较患有β-TT 的高血压患者与所有原因贫血和非贫血原发性高血压患者的 ABPM 特征。该研究最终纳入了 8861 例原发性高血压、非糖尿病患者，他们分为三组：I 组（n=191，β-TT）、II 组（n=655，贫血）和 III 组（n=8015，非贫血）。所有患者均接受了全面的临床、实验室和超声心动图评估，并且均接受了 ABPM。贫血定义为女性血红蛋白<12g/100ml，男性血红蛋白<13g/100ml，而β-TT 患者为自我报告。三组的昼夜节律模式分布分别为 61.3%、41.2%和 45.8%（P<0.001），而非杓型者分别为 20.4%、31.5%和 27.7%（P<0.001），超杓型者分别为 15.7%、15.0%和 17.5%（P<0.001），反杓型者分别为 2.6%、12.4%和 9.0%（P<0.001）。此外，三组日间收缩压（SBP）均值分别为 140.13±7.79mmHg、142.02±11.61mmHg 和 141.99±9.87mmHg（P=0.03），夜间 SBP 均值分别为 125.87±10.4mmHg、131.13±15.7mmHg 和 129.62±13.31mmHg（P<0.001）。多元回归分析显示，调整年龄、体重指数和血脂水平后，日间和夜间 SBP 的差异仍有统计学意义，分别为 140.18±9.84mmHg、142.02±9.85mmHg 和 141.99±9.85mmHg（P=0.04）和 125.99±13.07mmHg、131.19±13.08mmHg 和 129.61±13.07mmHg（P<0.001）。与贫血和非贫血的高血压患者相比，患有β-TT 的高血压患者具有更好的 24 小时血压谱。因此，β-TT 可能在其整体心血管风险谱中具有保护作用。
