TABLE 3.
Regression analyses with personality traits as predictors and the cortisol indexes as dependent variables, adjusted for age, sex, SES, BMI, awakening hour, and sleep/anxiety medication.
| CAR |
DCS |
|||||
| ΔR2 | Beta | p | ΔR2 | Beta | p | |
| Awakening hour | – | – | – | – | −0.225* | 0.046 |
| Neuroticism | 0.095 | 0.308** | 0.008 | 0.094 | 0.312** | 0.006 |
| Awakening hour | – | – | – | – | −0.272* | 0.013 |
| Conscientiousness | 0.064 | −0.254* | 0.029 | 0.114 | −0.338** | 0.002 |
| Awakening hour | – | – | – | – | −0.280* | 0.017 |
| Extraversion | 0.038 | −0.194 | 0.098 | 0.007 | −0.081 | 0.480 |
| Awakening hour | – | – | – | – | −0.302* | 0.010 |
| Openness | 0.012 | −0.111 | 0.348 | 0.023 | −0.158 | 0.167 |
| Awakening hour | – | – | – | – | −0.326** | 0.006 |
| Agreeableness | 0.000 | 0.019 | 0.871 | 0.024 | −0.163 | 0.164 |
CAR, cortisol awakening response; DCS, diurnal cortisol slope. ΔR: change R2. All covariates were excluded from the model, except awakening hour, which contributed to the relationship between personality traits and the DCS. *p < 0.05, **p < 0.01.