Table I.
Frequency of co-occurring medical, behavioral, developmental, and psychiatric conditions by group
| Characteristics | ASD n = 668 |
Developmental delays/ disorders n = 914 |
General population controls n = 884 |
P value |
|---|---|---|---|---|
| Medical conditions or symptoms | ||||
| Asthma, n (%) | 40 (6.0%) | 41 (4.5%) | 52 (5.9%) | .308 |
| Birth defects, n (%) | 37 (5.5%) | 68 (7.4%) | 20 (2.3%) | <.001†,‡ |
| Cardiac diseases/disorders, n (%) | 26 (3.9%) | 42 (4.6%) | 11 (1.2%) | <.001†,‡ |
| Endocrine diseases/disorders, n (%) | 10 (1.5%) | 20 (2.2%) | 4 (0.5%) | .007†,‡ |
| Gastrointestinal disorders/symptoms, n (%) | 161 (24.1%) | 165 (18.1%) | 154 (17.4%) | .002*,† |
| Genetic disorders, n (%) | 24 (3.6%) | 51 (5.6%) | 9 (1.0%) | <.001†,‡ |
| Immune disorders, n (%) | 0 (0%) | 4 (0.4%) | 5 (0.6%) | .169 |
| Metabolic disorders, n (%) | 2 (0.3%) | 3 (0.3%) | 2 (0.2%) | .917 |
| Neurological abnormalities/symptoms, n (%) | 47 (7.0%) | 47 (5.1%) | 10 (1.1%) | <.001†,‡ |
| Renal diseases/disorders, n (%) | 6 (0.9%) | 9 (1.0%) | 14 (1.6%) | .369 |
| Respiratory diseases/disorders, n (%) | 3 (0.5%) | 1 (0.1%) | 1 (0.1%) | .253 |
| Seizure disorders, n (%) | 24 (3.6%) | 26 (2.8%) | 1 (0.1%) | <.001†,‡ |
| Behavioral, developmental or psychiatric conditions or symptoms | ||||
| ADHD, n (%) | 52 (7.8%) | 65 (7.1%) | 5 (0.6%) | <.001†,‡ |
| Behavioral problems, n (%) | 104 (15.6%) | 81 (8.9%) | 18 (2.0%) | <.001*,†,‡ |
| Cognitive delay (Mullen < 70), n (%) | 5 (0.8%) | 2 (0.2%) | 2 (0.2%) | .157 |
| Feeding difficulties, n (%) | 48 (7.2%) | 34 (3.7%) | 22 (2.5%) | <.001*,† |
| Motor delay, n (%) | 127 (19.0%) | 138 (15.1%) | 11 (1.2%) | <.001*,†,‡ |
| Psychiatric disorders§ | 25 (3.7%) | 20 (2.2%) | 4 (0.5%) | <.001†,‡ |
| Sensory disorders, n (%) | 188 (28.1%) | 99 (10.8%) | 9 (1.0%) | <.001*,†,‡ |
| Sleep problems, n (%) | 43 (6.4%) | 24 (2.6%) | 5 (0.6%) | <.001*,†,‡ |
| Speech delay, n (%) | 426 (63.8%) | 525 (57.4%) | 76 (8.6%) | <.001*,†,‡ |
ADHD, attention-deficit/hyperactivity disorder; n, sample size.
*
Statistically significant difference between children with ASD and children with developmental delays/disorders (P < .05).
†
Statistically significant difference between children with ASD and general population control children (P < .05).
‡
Statistically significant difference between developmental delays/disorders and general population controls children (P < .05).
§
Including bipolar disorder, obsessive compulsive disorder, oppositional defiant disorder, and personality disorder.