Driscoll Ira, Shumaker Sally A, Snively Beverly M, Margolis Karen L, Manson JoAnn E, Vitolins Mara Z, Rossom Rebecca C, Espeland Mark A
Department of Psychology, University of Wisconsin-Milwaukee.
Department of Social Sciences and Health Policy and.
J Gerontol A Biol Sci Med Sci. 2016 Dec;71(12):1596-1602. doi: 10.1093/gerona/glw078. Epub 2016 Sep 27.
Nonhuman studies suggest a protective effect of caffeine on cognition. Although human literature remains less consistent, reviews suggest a possible favorable relationship between caffeine consumption and cognitive impairment or dementia. We investigated the relationship between caffeine intake and incidence of cognitive impairment or probable dementia in women aged 65 and older from the Women's Health Initiative Memory Study.
All women with self-reported caffeine consumption at enrollment were included (N = 6,467). In 10 years or less of follow-up with annual assessments of cognitive function, 388 of these women received a diagnosis of probable dementia based on a 4-phase protocol that included central adjudication. We used proportional hazards regression to assess differences in the distributions of times until incidence of probable dementia or composite cognitive impairment among women grouped by baseline level of caffeine intake, adjusting for risk factors (hormone therapy, age, race, education, body mass index, sleep quality, depression, hypertension, prior cardiovascular disease, diabetes, smoking, and alcohol consumption).
Women consuming above median levels (mean intake = 261mg) of caffeine intake for this group were less likely to develop incident dementia (hazard ratio = 0.74, 95% confidence interval [0.56, 0.99], p = .04) or any cognitive impairment (hazard ratio = 0.74, confidence interval [0.60, 0.91], p = .005) compared to those consuming below median amounts (mean intake = 64mg) of caffeine for this group.
Our findings suggest lower odds of probable dementia or cognitive impairment in older women whose caffeine consumption was above median for this group and are consistent with the existing literature showing an inverse association between caffeine intake and age-related cognitive impairment.
非人类研究表明咖啡因对认知有保护作用。尽管人类研究文献的结果仍不太一致，但综述表明咖啡因摄入与认知障碍或痴呆之间可能存在有利关系。我们在女性健康倡议记忆研究中调查了65岁及以上女性咖啡因摄入量与认知障碍或可能的痴呆发病率之间的关系。
纳入所有在入组时自我报告有咖啡因摄入的女性（N = 6467）。在10年或更短的随访期内，每年对认知功能进行评估，其中388名女性根据包括中央判定在内的四阶段方案被诊断为可能的痴呆。我们使用比例风险回归来评估按咖啡因摄入基线水平分组的女性发生可能的痴呆或复合认知障碍的时间分布差异，并对风险因素（激素治疗、年龄、种族、教育程度、体重指数、睡眠质量、抑郁、高血压、既往心血管疾病、糖尿病、吸烟和饮酒）进行调整。
与该组中咖啡因摄入量低于中位数（平均摄入量 = 64mg）的女性相比，摄入量高于中位数水平（平均摄入量 = 261mg）的女性发生痴呆（风险比 = 0.74，95%置信区间[0.56, 0.99]，p = 0.04）或任何认知障碍（风险比 = 0.74，置信区间[0.60, 0.91]，p = 0.005）的可能性更低。
我们的研究结果表明，对于该组中咖啡因摄入量高于中位数的老年女性，发生可能的痴呆或认知障碍的几率较低，这与现有文献表明咖啡因摄入与年龄相关认知障碍之间存在负相关一致。
