COPD可能增加脑微出血的风险

根据一项以人群为基础的前瞻性队列研究的结果，慢性阻塞性肺病(COPD)与脑微出血(脑内小血管疾病的一种标志物)风险增高相关，而与年龄、性别、吸烟状态和胆固醇水平等因素无关。

“抑郁症、体位不稳定性、认知和功能受损是已知的脑内小血管疾病的后果，同时也是COPD患者中常见的肺外表现，”比利时Ghent大学医院的Lies Lahousse医生及其同事说，“但尚不清楚COPD是否与脑内小血管疾病的发生相关。”

该研究纳入了参加鹿特丹扫描研究的165例COPD患者和645例非COPD患者。鹿特丹扫描研究是一项以人群为基础的队列研究，使用MRI评估年龄相关的脑变化。

结果显示，即使在校正年龄、性别、吸烟状态、动脉粥样硬化性大血管病变、抗血栓剂的使用、总胆固醇、甘油三酯和血清肌酐之后，COPD患者的脑微出血患病率仍显著高于肺功能正常患者[比值比(OR)，1.7；95%置信区间(CI)：1.15~2.47；P=0.007)。根据在线发表于7月19日的《美国呼吸与重症医学杂志》上的这篇文章的数据，COPD患者深部或小脑天幕下微出血的患病率也增加2倍以上(OR，3.3；95%CI：1.97~5.53；P＜0.001)。

对基线时无微出血的患者进行的纵向分析显示，在中位数为3.42年的时间段内，COPD可独立预测深部或小脑天幕下微出血风险增加6倍(OR，7.1；95%CI：2.1~24.5；P=0.002)。

“我们的结果与之前的两项横断面研究一致，显示COPD患者脑白质病变体积显著增加，这是脑内小血管疾病的另一标志物，并且已知与深部或小脑天幕下区域的微出血相关。”尽管COPD患者中微出血发生率增高与吸烟状态无关，但研究者发现，在吸烟者中，脑微出血的患病率显著增高。既往研究显示，COPD患者动脉粥样硬化性大血管病变患病率增高，在这项分析中也考虑了这一因素。

研究者认为，鉴于脑微出血可能造成认知和功能障碍，该研究结果有助于识别易感患者人群，并提示有必要开展更多关于预防策略的研究。

该研究由学术研究Flanders项目基金和荷兰学术研究组织资助。

爱思唯尔版权所有  未经授权请勿转载

By: BIANCA NOGRADY, Cardiology News Digital Network

Chronic obstructive pulmonary disease was associated with an increased risk of cerebral microbleeds – a marker of cerebral small vessel disease – independent of factors such as age, sex, smoking status, and cholesterol levels, according to a prospective, population-based cohort study.

"Depression, postural instability, cognitive and functional impairment are known consequences of cerebral small-vessel disease, and are frequently described extrapulmonary manifestations in patients with COPD," wrote Dr. Lies Lahousse from Ghent University Hospital, Belgium, and colleagues. "However, it is unclear whether COPD is associated with incident cerebral small-vessel disease."

Patients with COPD had a significantly higher prevalence of cerebral microbleeds, compared with patients with normal lung function, even after accounting for age, sex, smoking status, atherosclerotic macroangiopathy, antithrombotic use, total cholesterol, triglycerides, and serum creatinine (odds ratio, 1.7; 95% confidence interval, 1.15-2.47; P = .007).

Patients with COPD also had a more than threefold increase in the prevalence of microbleeds in deep or infratentorial locations (OR, 3.3; 95% CI, 1.97-5.53; P less than .001), according to data published online July 19 in the American Journal of Respiratory and Critical Care Medicine.

When a longitudinal analysis was conducted in patients without microbleed at baseline, COPD independently predicted a sevenfold increase in risk of deep or infratentorial microbleeds (OR, 7.1; 95% CI, 2.1-24.5; P = .002) over a median time interval of 3.42 years.

"Our results are in line with two previous cross-sectional studies that showed that patients with COPD had a significantly increased volume of cerebral white matter lesions, which is another marker of cerebral small vessel disease, and known to be associated with microbleeds in a deep or infratentorial region," Dr. Lahousse and associates said.

Although the increased incidence of microbleeds in patients with COPD was independent of smoking status, the researchers did find a significantly higher prevalence of cerebral microbleeds among individuals who had smoked.

The study involved 165 patients with COPD and 645 patients without COPD who were enrolled in the Rotterdam Scan Study, a population-based cohort study using MRI scan to examine age-related brain changes.

Previous research had shown an increased prevalence of atherosclerotic macroangiopathy in patients with COPD, but that was taken into account in the analysis.

The authors therefore suggested that COPD may affect large and small blood vessels, and that stiffening of arteries and arterioles may be the result of systemic inflammation in COPD as well as hypoxia caused by airflow limitation.

"Although severity of airflow limitation may not entirely reflect disease activity, our results suggest that cerebral small vessel disease is more present in COPD patients with more severe airflow limitation," the investigators noted.

Given the potential cognitive and functional consequences of microbleeds, the study authors suggested that the results could help with identification of vulnerable patient groups and point to the need for more research into preventive strategies.

The study was funded by the Fund for Scientific Research Flanders project and the Netherlands Organization for Scientific Research.