與無明顯并發(fā)癥的患者相比,伴有冠心病的糖代謝異?;颊叩慕堤侵委熅哂性S多特殊性。只有遵循循證醫(yī)學(xué)證據(jù),采取積極篩查、早期干預(yù)、平穩(wěn)降糖、綜合防控的血糖管理策略,方能最大程度的降低患者心血管事件危險性并改善其預(yù)后。 一、大力提倡在冠心病及其高危人群中常規(guī)篩查糖代謝異常 在臨床工作中,應(yīng)將血糖檢測做為冠心病及其高危人群的常規(guī)檢查項目之一??紤]到臨床實際工作中的可操作性,對于在心內(nèi)科住院的穩(wěn)定性患者可采用簡化的口服糖耐量試驗(僅檢測FBG與負荷后2小時血糖)進行篩查,門診患者可應(yīng)用快速血糖檢測儀進行篩查。確診糖尿病的患者應(yīng)進一步檢測HbA1C,為確定治療方案以及療效監(jiān)測提供依據(jù),并視具體情況轉(zhuǎn)由糖尿病專家診治。 根據(jù)患者血糖增高的特征,可將其分為糖代謝正常、FBG、IGT、糖尿病四種情況。其定義及分類如下: 糖代謝正常:FBG<6.1mmol/l,且OGTT2h血糖<7.8mmol/l; IGT:FBG<6.1mmol/l,OGTT2h血糖≥7.8 ~<11.1mmol/l; IFG:FBG≥6.1~<7.0mmol/l,且OGTT2h血糖<7.8mmol/l; 糖尿病:1. 糖尿病癥狀+任意時間血漿葡萄糖水平≥11.1mmol/l,或2. 空腹血漿葡萄糖水平≥7.0mmol/l,或3. OGTT2h血糖≥11.1mmol/l(確診無癥狀患者,需要不同時間2次檢驗結(jié)果異常)。 二、早期干預(yù)與平穩(wěn)降糖應(yīng)成為穩(wěn)定性冠心病患者血糖管理的核心策略 如前所述,早期干預(yù)冠心病患者的糖代謝異常是改善患者預(yù)后的關(guān)鍵措施。對于存在IFG和/或IGT的冠心病患者,應(yīng)采取以改善生活方式(合理飲食、增加運動、控制體重等)為基礎(chǔ)的干預(yù)措施,并視患者具體情況酌情應(yīng)用a-糖苷酶抑制劑或雙胍類藥物進行降糖治療。 糖尿病患者的降糖治療目標值是目前爭論的熱點問題之一。對于一般糖尿病患者,多數(shù)學(xué)術(shù)機構(gòu)推薦將HbA1c控制在6.5-7.0%以下。然而如前所述,低血糖事件對心血管病高?;颊哳A(yù)后可產(chǎn)生顯著的不利影響,因此對于此類患者應(yīng)采取較寬松的降糖治療策略,并根據(jù)其整體危險水平確定個體化的血糖目標值。追求過低的血糖水平可能會顯著增加低血糖事件的發(fā)生率而對患者預(yù)后產(chǎn)生不良影響。對于高齡、糖尿病病史較長、心血管整體危險水平較高、具有嚴重低血糖事件史、預(yù)期壽命較短以及并存多種疾病的患者,建議血糖目標值為FBG<140mg/d1(7.8mmo1/L),負荷后2小時血糖<200mg/d1(11.1mmo1/L)。對于此類患者,應(yīng)慎重對待低于7.0%的HbA1C目標值。 三、多重危險因素綜合干預(yù)是改善患者預(yù)后的有效手段 對于伴有糖代謝異常的穩(wěn)定性冠心病患者不應(yīng)僅僅關(guān)注其血糖水平,應(yīng)在積極穩(wěn)妥的控制血糖的同時,認真篩查患者可能存在的其他危險因素并予以積極有效的干預(yù)。 1. 嚴格控制血壓水平:大量研究表明,嚴格控制糖尿病患者的血壓(目標值<130/80 mmHg)可以有效減少心血管事件的發(fā)生。對2型糖尿病患者而言,降壓治療與降糖治療同樣重要,甚至有研究顯示對糖尿病患者積極有效的降壓治療所帶來的大血管獲益比嚴格的血糖控制更為顯著。由于血管緊張素轉(zhuǎn)換酶抑制劑或血管緊張素受體拮抗劑對糖代謝可能具有有益的作用,可首先考慮用于糖尿病患者的降壓治療。對于一般高血壓患者,單種降壓藥物只能使不足1/3的高血壓患者血壓達標(140/90mmHg以下),故多數(shù)患者均需要聯(lián)合應(yīng)用降壓藥物。對于伴發(fā)糖尿病的冠心病患者,因其降壓目標值更低(130/80 mmHg以下),因此更多患者需要聯(lián)合用藥方能使血壓達標。除血管緊張素轉(zhuǎn)換酶抑制劑或血管緊張素受體拮抗劑可以優(yōu)先選用外,也可考慮單獨或聯(lián)合應(yīng)用鈣通道阻滯劑、噻嗪類利尿劑和b-受體阻滯劑,但由于后兩類藥物對糖代謝具有潛在的不良影響,應(yīng)避免大劑量聯(lián)合應(yīng)用。 2. 積極控制血脂達標:血脂異常是糖尿病和冠心病患者最常伴隨的代謝紊亂,并可顯著增加心血管終點事件危險性。調(diào)脂治療應(yīng)當根據(jù)糖尿病患者異常血脂譜合理選用血脂異常治療藥物。對于LDL-C>2.6mmol/L冠心病糖尿病患者,積極使用他汀類藥物降低膽固醇水平,LDL-C水平控制于70-80mg/dl,有助于減少心血管事件并改善患者預(yù)后;對于LDL-C<2.6mmol/L的冠心病伴糖尿病患者,如果存在TG>2.3mmol/L或HDL-C<0.91mmol/L,宜選用貝特或煙酸類藥物;對于使用了他汀的冠心病糖尿病患者,如果LDL-C已達標、TG>2.3mmol/L或HDL-C<0.91mmol/L,可以考慮聯(lián)合應(yīng)用貝特類或煙酸類藥物。 3. 合理應(yīng)用阿司匹林:許多隨機化對照試驗證實,長期服用小劑量阿司匹林(每日75-150mg)可以有效降低糖尿病患者心腦血管事件發(fā)生率,加之其低廉的價格和良好的安全性,應(yīng)在臨床上大力推廣應(yīng)用。 4. 積極改善生活方式:積極改善生活方式可以有效降低伴有糖代謝異常的冠心病患者心血管事件的危險性,被視為心血管疾病一級與二級預(yù)防的基石。其主要內(nèi)容包括合理的飲食結(jié)構(gòu)與熱量攝入、增加體力運動、控制體重、戒煙等。對于輕度的糖代謝異常(特別是IFG與IGT),有效改善生活方式可以延緩甚至避免糖尿病的發(fā)生。對于已經(jīng)發(fā)生糖尿病者,改善生活方式可以增進藥物治療效果并減少用藥劑量。然而在臨床實踐中,這些措施遠未受到充分重視,故今后應(yīng)努力提高醫(yī)生與患者對改善生活方式重要性的認識。 結(jié) 語 糖尿病或糖尿病前期在冠心病患者中廣泛存在,并可顯著影響其預(yù)后。與FBG相比,負荷后血糖能夠更為可靠的預(yù)測全因死亡與心血管性死亡。在臨床實踐中,需加強在冠心病患者或僅存在冠心病危險因素的人群中篩查糖代謝異常,F(xiàn)BG與OGTT試驗應(yīng)作為冠心病患者的常規(guī)檢測項目。伴有冠心病的糖尿病患者的降糖治療措施與目標有別于單純糖尿病患者,積極篩查、早期干預(yù)、平穩(wěn)降糖、綜合防控多重危險因素是其核心策略。加強冠心病患者及其高危人群的血糖管理是心血管科醫(yī)生與內(nèi)分泌科醫(yī)生的共同使命。 參考文獻 1. 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