National Clinical Research Center (CIC), Havana, Cuba.
MEDICC Rev. 2012 Jan;14(1):18-24. doi: 10.37757/MR2012V14.N1.5.
Silent myocardial ischemia is frequent in type 2 diabetics, therefore, symptoms cannot be relied upon for diagnosis and followup in these patients. Various studies relate blood lipid levels to cardiovascular diseases, and several authors describe certain lipoproteins as independent predictors of ischemia.
Identify blood lipid levels that predict silent myocardial ischemia in a type 2 diabetic population in Havana.
From May 2005 through May 2009, assessment was done of 220 asymptomatic type 2 diabetics in ten polyclinics in Havana using laboratory tests and Single-Photon Emission-Computed Tomography, synchronized with electrocardiogram, known as gated SPECT (gSPECT). Coronary angiography was used for confirmation when gSPECT detected ischemia. Patients were classified into two groups: gSPECT positive and gSPECT negative. Descriptive statistics (mean and standard deviation) were calculated for all variables and mean comparison tests were conducted. Classification trees were developed relating lipid values to gSPECT results, identifying optimal cutoff points for their use as indicators of silent myocardial ischemia in the total study population and for each sex separately.
GSPECT found silent myocardial ischemia in 29.1% of those examined, and 68.4% of angiograms found multivessel disease. gSPECT-positive diabetics had higher levels of total cholesterol, LDL, and triglycerides (p < 0.05). HDL levels were lower in this group (p < 0.05). Classification trees showed optimal cutoff points, indicators for silent ischemia, for: HDL ≤44 mg/dL, LDL >119.9 mg/dL, and triglycerides >107.2 mg/d; 80.4% of diabetics with these HDL and triglyceride values had ischemia. HDL was the most important normalized variable when the entire population was analyzed. Analysis by sex showed a greater percentage of silent ischemia in men (33.3%) than in women (24.8%). The most important normalized variables were LDL of >100.8 mg/dL for men and HDL of ≤44 mg/dL for women.
A considerable percentage of the study population had silent myocardial ischemia. Type 2 diabetics with ischemia had higher levels of total cholesterol, LDL and triglycerides. HDL levels were significantly lower in these patients. The association of low HDL with high triglycerides was a strong indicator of myocardial ischemia in type 2 diabetics without clinical cardiovascular signs. KEYWORDS Lipids, type 2 diabetes, silent myocardial ischemia, decision trees, diagnostic imaging, Single-Photon Emission-Computed Tomography, cardiac-gated SPECT, early detection, Cuba.
2 型糖尿病患者常发生无症状心肌缺血，因此不能仅依靠症状进行这些患者的诊断和随访。多项研究表明血脂水平与心血管疾病相关，一些作者还描述了某些脂蛋白是缺血的独立预测因子。
确定哈瓦那 2 型糖尿病患者中预测无症状心肌缺血的血脂水平。
2005 年 5 月至 2009 年 5 月，在哈瓦那的 10 家综合诊所对 220 例无症状 2 型糖尿病患者进行了评估，使用实验室检查和单光子发射计算机断层扫描（同步心电图，称为门控 SPECT（gSPECT））。当 gSPECT 检测到缺血时，使用冠状动脉造影进行确认。将患者分为 gSPECT 阳性和 gSPECT 阴性两组。对所有变量进行描述性统计（均值和标准差），并进行均值比较检验。为了确定脂质值与 gSPECT 结果的关系，开发了分类树，确定了总研究人群和每个性别中用于无症状心肌缺血的最佳截断值。
gSPECT 发现 29.1%的受检者存在无症状心肌缺血，68.4%的血管造影显示多血管疾病。gSPECT 阳性的糖尿病患者总胆固醇、LDL 和甘油三酯水平更高（p<0.05）。该组的 HDL 水平较低（p<0.05）。分类树显示了最佳截断值，即 HDL≤44mg/dL、LDL>119.9mg/dL 和甘油三酯>107.2mg/dL，这些 HDL 和甘油三酯值的 80.4%的糖尿病患者存在缺血。当分析整个人群时，HDL 是最重要的归一化变量。按性别分析显示，男性（33.3%）的无症状心肌缺血比例高于女性（24.8%）。男性最重要的归一化变量是 LDL>100.8mg/dL，女性是 HDL≤44mg/dL。
研究人群中有相当大比例的人存在无症状心肌缺血。有缺血的 2 型糖尿病患者总胆固醇、LDL 和甘油三酯水平较高。这些患者的 HDL 水平显著降低。低 HDL 与高甘油三酯的联合是无临床心血管体征的 2 型糖尿病患者心肌缺血的一个强有力指标。
血脂、2 型糖尿病、无症状心肌缺血、决策树、诊断成像、单光子发射计算机断层扫描、心脏门控 SPECT、早期检测、古巴。
