Table 2

Associations between diurnal cortisol patterns and cognitive performance—in the full sample, and stratified by normal/abnormal CSF Aβ42 levels (laboratory-recommended cut-off), plus p values for interactions cortisol*Aβ42 for each of the cortisol measures

Overall cognitionP value (interaction)MemoryP value (interaction)Working memoryP value (interaction)Processing speedP value (interaction)Perceptual reasoningP value (interaction)
b95% CIpb95% CIpb95% CIpb95% CIpb95% CIp
All(n=125)(n=134)(n=110)(n=124)(n=127)
 Awakening cortisol (t1)0.01−0.22 to 0.250.919−0.24−0.50 to 0.020.0700.11−0.21 to 0.420.4980.280.01 to 0.540.042*0.03−0.23 to 0.270.845
 Bedtime cortisol (t6)−0.11−0.24 to 0.020.102−0.07−0.21 to 0.080.3810.03−0.15 to 0.200.7500−0.15 to 0.150.991−0.09−0.23 to 0.060.230
 Cortisol awakening response−0.02−0.13 to 0.100.7510.11−0.01 to 0.230.080−0.03−0.19 to 0.120.6600.04−0.09 to 0.160.5520.01−0.11 to 0.130.900
 Daily cortisol output–0.07−0.27 to 0.130.479−0.08−0.31 to 0.140.4560.06−0.21 to 0.330.6660.12−0.10 to 0.350.277−0.03−0.24 to 0.180.770
 Cortisol AM/PM ratio (t1/t6)0.180.00 to 0.360.052−0.01−0.22 to 0.210.9390−0.24 to 0.250.9780.14−0.08 to 0.350.2120.14−0.05 to 0.340.151
42 ≥550 ng/L(n=75)(n=80)(n=68)(n=76)(n=76)
 Awakening cortisol (t1)0.12−0.18 to 0.420.4390.068−0.17−0.49 to 0.140.2710.024*0.12−0.27 to 0.520.5430.4680.350.01 to 0.700.047*0.3850.08−0.25 to 0.410.6220.229
 Bedtime cortisol (t6)−0.19−0.34 to −0.040.016*0.428−0.09−0.25 to 0.080.2910.841−0.06−0.26 to 0.140.5460.297−0.02−0.21 to 0.170.8550.924−0.13−0.30 to 0.040.1230.884
 Cortisol awakening response0.01−0.12 to 0.140.9190.6520.08−0.05 to 0.220.2280.493−0.02−0.20 to 0.160.8010.778−0.03−0.19 to 0.120.6620.0980.03−0.11 to 0.170.6730.678
 Daily cortisol output−0.1−0.34 to 0.140.4180.908−0.07−0.33 to 0.190.5750.59−0.05−0.38 to 0.290.7730.5750.03−0.26 to 0.320.8540.383−0.06−0.33 to 0.210.6360.784
 Cortisol AM/PM ratio (t1/t6)0.380.17 to 0.59<0.001***0.016*0.09−0.16 to 0.330.4810.1470.15−0.14 to 0.440.3100.1280.19−0.08 to 0.460.1570.5450.260.02 to 0.500.035*0.397
42 <550 ng/L(n=36)(n=37)(n=29)(n=32)(n=36)
 Awakening cortisol (t1)−0.41−0.93 to 0.110.114−0.78−1.19 to −0.36<0.001***−0.13−0.87 to 0.610.7180.06−0.44 to 0.570.797−0.26−0.80 to 0.270.320
 Bedtime cortisol (t6)−0.02−0.33 to 0.290.895−0.09−0.36 to 0.180.4840.23−0.18 to 0.640.2570.01−0.27 to 0.280.961−0.11−0.42 to 0.190.460
 Cortisol awakening response−0.09−0.37 to 0.190.5120.2−0.02 to 0.420.067−0.13−0.50 to 0.240.4820.19−0.01 to 0.400.063−0.06−0.34 to 0.220.677
 Daily cortisol output−0.18−0.57 to 0.210.352−0.25−0.63 to 0.140.2040.11−0.44 to 0.650.6920.21−0.17 to 0.580.265−0.18−0.57 to 0.220.368
 Cortisol AM/PM ratio (t1/t6)−0.18−0.59 to 0.220.365−0.28−0.68 to 0.120.166−0.36−0.90 to 0.180.1810.01−0.40 to 0.420.9610.02−0.39 to 0.430.926
  • Results based on linear regressions. All analysis adjusted for age, sex, education. *p<0.05, **p<0.01; ***p<0.001.

  • Aβ, beta-amyloid; CSF, cerebrospinal fluid .