Johar Hamimatunnisa, Emeny Rebecca T, Bidlingmaier Martin, Lacruz Maria Elena, Reincke Martin, Peters Annette, Heier Margit, Ladwig Karl-Heinz
Institute of Epidemiology II, Helmholtz Zentrum München, German Research Centre for Environmental Health, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
Medizinische Klinik und Poliklinik IV, Klinikum der Ludwig-Maximilians-Universität München, Munich, Germany.
Psychoneuroendocrinology. 2015 Jan;51:296-306. doi: 10.1016/j.psyneuen.2014.10.011. Epub 2014 Oct 23.
A dysregulated hypothalamic-pituitary-adrenocortical axis (HPA) is thought to play a role in the pathophysiology of cognitive impairment. Surprisingly, little agreement exists on the association of cortisol and cognitive impairment. Thus, we sought to examine the association between cognitive function and salivary cortisol levels in a representative sample of older men and women.
A cross-sectional analysis was conducted among 733 study participants (65-90 years old, mean age=74.9) of the population-based KORA (Cooperative Health Research in the Region of Augsburg)-Age study. Associations were examined between cognitive function (determined by telephone interview for cognitive status-modified, TICS-m) and salivary cortisol measured upon waking (M1), 30min after awakening (M2), and in the late evening (E).
In a dose response manner, lower morning (M1 and M2), and increased evening levels were observed in participants with probable dementia (4.5%, N=33) and slightly increased in those with mild cognitive impairment (MCI) (13.8%, N=101) compared to healthy individuals. Higher morning to evening ratios were associated with reduced odds of cognitive impairment, even after adjustments for important confounders (M1/E ratio: OR=1.50, 95% CI=1.08-2.07, M2/E ratio: 1.41, 1.01-1.95, per 1 standard deviation (SD) increase). However, the significant association of an increased risk for cognitive impairment was observed among men (M1/E: OR=1.94, 95% CI=1.24-3.02; M2/E=1.74, 1.12-2.71) but not women (M1/E: OR=1.11, 0.69-1.78; M2/E=1.09, 0.67-1.77).
Our findings suggest that dysregulated HPA axis reactivity, evidenced by blunted diurnal cortisol responses, are associated with impaired cognitive function in an aged population.
下丘脑 - 垂体 - 肾上腺皮质轴（HPA）功能失调被认为在认知障碍的病理生理学中起作用。令人惊讶的是，关于皮质醇与认知障碍之间的关联，目前存在的共识很少。因此，我们试图在老年男性和女性的代表性样本中研究认知功能与唾液皮质醇水平之间的关联。
对基于人群的奥格斯堡地区合作健康研究（KORA） - 年龄研究中的733名研究参与者（65 - 90岁，平均年龄 = 74.9岁）进行横断面分析。研究了认知功能（通过电话访谈认知状态修正版，TICS - m确定）与醒来时（M1）、醒来后30分钟（M2）和傍晚（E）测量的唾液皮质醇之间的关联。
与健康个体相比，可能患有痴呆症的参与者（4.5%，N = 33）早晨（M1和M2）皮质醇水平较低，傍晚水平升高，而患有轻度认知障碍（MCI）的参与者（13.8%，N = 101）傍晚皮质醇水平略有升高，呈现剂量反应关系。即使在调整重要混杂因素后，早晨与傍晚皮质醇水平比值较高与认知障碍几率降低相关（M1/E比值：OR = 1.50，95% CI = 1.08 - 2.07；M2/E比值：1.41，1.01 - 1.95，每增加1个标准差（SD））。然而，仅在男性中观察到认知障碍风险增加的显著关联（M1/E：OR = 1.94，95% CI = 1.24 - 3.02；M2/E = 1.74，1.12 - 2.71），女性中未观察到（M1/E：OR = 1.11，0.69 - 1.78；M2/E = 1.09，0.67 - 1.77）。
我们的研究结果表明，HPA轴反应性失调，表现为昼夜皮质醇反应迟钝，与老年人群认知功能受损有关。
