Stump T E, Callahan C M, Hendrie H C
Indiana University Center for Aging Research, Regenstrief Institute for Health Care, Indianapolis, Indiana 46202-2859, USA.
J Am Geriatr Soc. 2001 Jul;49(7):934-40. doi: 10.1046/j.1532-5415.2001.49184.x.
To assess the impact of cognitive impairment on mortality in older primary care patients after controlling for confounding effects of demographic and comorbid chronic conditions.
Prospective cohort study.
Academic primary care group practice.
Three thousand nine hundred and fifty-seven patients age 60 and older who completed the Short Portable Mental Status Questionnaire (SPMSQ) during routine office visits.
Cognitive impairment measured at baseline using the SPMSQ, demographics, problem drinking, history of smoking, clinical data (including weight, cholesterol level, and serum albumin), and comorbid chronic conditions collected at baseline; survival time measured during the 5 to 7 years after baseline.
Eight hundred and eighty-six patients (22.4%) died during the 5 to 7 years of follow-up. Cognitive impairment was categorized as having no impairment (84.3%), mild impairment (10.5%), and moderate-to-severe impairment (5.2%) based on SPMSQ score. Chi-square tests revealed that patients with moderate-to-severe impairment were significantly more likely to die compared with patients with mild impairment (40.8% vs 21.5%) and those with no impairment (40.8% vs 21.4%). No significant difference in crude mortality was found between patients with no impairment and those with mild impairment. After analyzing time to death using the Kaplan-Meier method, patients with moderate-to-severe cognitive impairment were at increased risk of death compared with those with no or mild impairment (Log-rank chi(2) = 55.5; P <.0001). Even in multivariable analyses using Cox proportional hazards to control for confounding factors, compared with those with no impairment, moderately-to-severely impaired patients had an increased risk of death, with a hazard ratio (HR) of 1.70. Increased risk of death was also associated with older age (HR = 1.03 for each year), a history of smoking (HR = 1.48), having a serum albumin level <3.5 g/L (HR = 1.29), and weighing less than 90% of the ideal body weight (HR = 1.98). Outpatient diagnoses associated with increased mortality risk were diabetes mellitus, coronary artery disease, congestive heart failure, cerebrovascular disease, cancer, anemia, and chronic obstructive pulmonary disease (HR range 1.36-1.67). Factors protective of mortality risk included female gender (HR = 0.67) and black race (HR = 0.73).
Moderate-to-severe cognitive impairment is associated with an increased risk of mortality, even after controlling for confounding effects of demographic and clinical characteristics. Mild cognitive impairment is not associated with mortality risk, but a longer follow-up period may be necessary to identify this risk if it exists.
在控制人口统计学和共病慢性病的混杂效应后，评估认知障碍对老年初级保健患者死亡率的影响。
前瞻性队列研究。
学术性初级保健团体诊所。
3957名60岁及以上的患者，他们在常规门诊就诊时完成了简易便携式精神状态问卷（SPMSQ）。
在基线时使用SPMSQ测量认知障碍、人口统计学、问题饮酒、吸烟史、临床数据（包括体重、胆固醇水平和血清白蛋白）以及在基线时收集的共病慢性病；在基线后5至7年测量生存时间。
在5至7年的随访期间，886名患者（22.4%）死亡。根据SPMSQ评分，认知障碍分为无损害（84.3%）、轻度损害（10.5%）和中度至重度损害（5.2%）。卡方检验显示，与轻度损害患者（40.8%对21.5%）和无损害患者（40.8%对21.4%）相比，中度至重度损害患者死亡的可能性显著更高。无损害患者和轻度损害患者之间的粗死亡率没有显著差异。使用Kaplan-Meier方法分析死亡时间后，与无或轻度认知障碍患者相比，中度至重度认知障碍患者死亡风险增加（对数秩卡方=55.5；P<.0001）。即使在使用Cox比例风险模型进行多变量分析以控制混杂因素时，与无损害患者相比，中度至重度损害患者的死亡风险增加，风险比（HR）为1.70。死亡风险增加还与年龄较大（每年HR=1.03）、吸烟史（HR=1.48）、血清白蛋白水平<3.5 g/L（HR=1.29）以及体重低于理想体重的90%（HR=1.98）有关。与死亡风险增加相关的门诊诊断包括糖尿病、冠状动脉疾病、充血性心力衰竭、脑血管疾病、癌症、贫血和慢性阻塞性肺疾病（HR范围1.36-1.67）。对死亡风险有保护作用的因素包括女性（HR=0.67）和黑人种族（HR=0.73）。
即使在控制人口统计学和临床特征的混杂效应后，中度至重度认知障碍仍与死亡风险增加相关。轻度认知障碍与死亡风险无关，但如果存在这种风险，可能需要更长的随访期来识别。
