Table 1. Risk of Mental Disorders in Individuals With Positive or Negative Streptococcal Test Resultsa.
| Result of Streptococcal Test | Any Mental Disorder | OCD | Tic Disorders | ||||||
|---|---|---|---|---|---|---|---|---|---|
| No. | IRRb (95% CI) | IRRc (95% CI) | No. | IRRb (95% CI) | IRRc (95% CI) | No. | IRRb (95% CI) | IRRc (95% CI) | |
| No test performed | 13 712 | 1 [Reference] | 1 [Reference] | 206 | 1 [Reference] | 1 [Reference] | 522 | 1 [Reference] | 1 [Reference] |
| Positive | 15 408 | 1.18 (1.15-1.21)d | 1.16 (1.14-1.20)d | 556 | 1.51 (1.28-1.77)d | 1.49 (1.27-1.76)d | 993 | 1.35 (1.21-1.50)d | 1.34 (1.20-1.49)d |
| Negative | 11 315 | 1.08 (1.06-1.11)d | 1.07 (1.04-1.09)d | 316 | 1.28 (1.07-1.53)d | 1.27 (1.07-1.52)d | 662 | 1.25 (1.12-1.41)d | 1.24 (1.10-1.39)d |
Abbreviations: IRR, incidence rate ratio; OCD, obsessive-compulsive disorder.
a
The streptococcal test was the rapid antigen diagnostic test for group A β-hemolytic streptococcal throat infections.
b
Adjusted for sex, age, and calendar year.
c
Further adjusted for parental educational level, income, marital status, family history of psychiatric disorders, and personal or parental history of autoimmune diseases.
d
The reference interval did not include 1 [Reference].