Table 5. Univariable and Multivariable Mediation Analyses of the Association Between Population Density/Deprivation at Birth and Risk of Nonaffective Psychosis by IQ at 18 Years of Agea.
| Pathways and Mediation Effects | Unadjusted Model | Fully Adjusted Modelb | ||
|---|---|---|---|---|
| Effect Estimate (95% CI) | P Value | Effect Estimate (95% CI) | P Value | |
| Deprivation | ||||
| Path A (exposure-mediator)c | −1.58 (−1.68 to −1.48) | <.001 | −0.70 (−0.78 to −0.62) | <.001 |
| Path B (mediator-outcome)d | 0.71 (0.68 to 0.75) | <.001 | 0.70 (0.67 to 0.74) | <.001 |
| Path C (exposure-outcome)e | 1.18 (1.12 to 1.23) | <.001 | 1.07 (1.02 to 1.13) | .005 |
| Mediation model | ||||
| Total effect | 1.19 (1.14 to 1.23) | <.001 | 1.08 (1.03 to 1.13) | .001 |
| Natural direct effect | 1.14 (1.10 to 1.19) | <.001 | 1.06 (1.01 to 1.11) | .01 |
| Natural indirect effect | 1.04 (1.03 to 1.04) | <.001 | 1.02 (1.01 to 1.02) | <.001 |
| Mediation by IQ, % | 22 (21 to 25) | NA | 23 (17 to 49) | NA |
Abbreviation: NA, not applicable.
a
Includes participants with no missing data (n = 227 429).
b
Adjusted for paternal age at birth, family income, maternal educational level, paternal educational level, any psychosis or bipolar disorder in parents, and parent(s) born outside of Sweden.
c
Indicates change in IQ Score at 18 years of age, per SD increase in deprivation at birth.
d
Indicates odds of nonaffective psychosis, per SD increase in IQ at 18 years of age.
e
Indicates odds of nonaffective psychosis, per SD increase in deprivation at birth.