TABLE 5.
Developmental and other neurological disorders diagnosed in individuals with CDD compared with those with other infantile-onset epilepsies with a suspected or defined genetic etiology
| Clinical feature | CDD | Other infantile-onset epilepsies | p | Other infantile-onset no genetic diagnosis | p | Other infantile-onset confirmed genetic epilepsies | p |
|---|---|---|---|---|---|---|---|
|
| |||||||
| n (%) | n (%) | n (%) | n (%) | ||||
| Total cohort | 137a | 313b | 203c | 110d | |||
| Autism (≥3 years) | 10 (14.7)f | 54 (25.6) | 0.069 | 40 (28.4) | 0.037 | 14 (20.0) | 0.502 |
| Intellectual disability (≥5 years) | 64 (100) | 104 (77.0) e | <0.001 | 78 (78.0) e | <0.0001 | 26 (74.3) f | <0.001 |
| Mild/moderate | 1 (1.6) | 28 (26.9) | <0.001 | 19 (24.4) | <0.0001 | 9 (34.6) | <0.001 |
| Severe/profound | 63 (98.4) | 70 (67.3) | 54 (69.2) | 16 (61.5) | |||
| Unknown | 0 | 6 (5.8) | 5 (6.4) | 1 (3.8) | |||
| Development | <0.001 | <0.001 | <0.001 | ||||
| Normal development | 0 | 47 (15.2) | 34 (16.9) | 13 (11.9) | |||
| Global developmental delay | 133 (100) | 240 (77.4) | 154 (76.6) | 86 (78.9) | |||
| Delays in one area only | 0 | 23 (7.4) | 13 (6.5) | 10 (9.2) | |||
| Global developmental delay (≥1 year) | 121 (100) | 227 (79.1) | <0.001 | 144 (78.3) | <0.001 | 83 (80.6) | <0.001 |
| Any developmental regression | 69 (52.3) | 89 (29.0) | <0.001 | 57 (28.6) | <0.001 | 32 (29.6) | <0.001 |
| No regression | 63 (47.7) | 218 (71.0) | 142 (71.4) | 76 (70.4) | |||
| Yes, independent of seizures/change in EEG | 13 (9.8) | 10 (3.3) | 6 (3.0) | 4 (3.7) | |||
| Yes, in the setting of epileptic encephalopathy | 35 (26.5) | 73 (23.8) | 50 (25.1) | 23 (21.3) | |||
| Yes, unknown setting | 21 (15.9) | 6 (2.0) | 1 (0.5) | 5 (4.6) | |||
| Stereotypies | 89 (68.5) | 35 (11.3) | <0.001 | 22 (10.9) | <0.001 | 13 (12.0) | <0.001 |
| Any movement disorder | 34 (28.8) f | 52 (16.7) | 0.005 | 28 (13.8) | 0.001 | 24 (22.0) | 0.241 |
| Choreoathetosis | 11 (9.3) | 14 (4.5) | 7 (3.5) | 7 (6.2) | |||
| Dystonia (paroxysmal) | 13 (11.0) | 12 (3.8) | 6 (3.0) | 6 (5.3) | |||
| Tremors | 3 (2.5) | 7 (2.2) | 4 (2.0) | 3 (2.7) | |||
| Dyskinesias | 6 (5.1) | 8 (2.6) | 4 (2.0) | 4 (3.5) | |||
| Tics | 0 | 3 (1.0) | 2 (1.0) | 1 (0.9) | |||
| Non-epileptic myoclonus | 1 (0.8) | 8 (2.6) | 5 (2.5) | 3 (2.7) | |||
| Ataxia | 1 (0.8) | 4 (1.3) | 2 (1.0) | 2 (1.8) | |||
| Other | 4 (3.4) | 4 (1.3) | 3 (1.5) | 1 (0.9) | |||
| Cerebral visual impairment (≥2 years) | 90 (87.4) | 71 (28.0) | <0.001 | 49 (29.3) | <0.001 | 22 (25.3) | <0.001 |
The p-values were calculated from χ2 or Fisher’s exact tests compared with the CDD cohort. Significant clinical features are set in bold type after Benjamini–Hochberg correction on the basis of a false discovery rate of 0.2.
Numbers for cohorts with age cutoffs: ≥1 year = 123, ≥2 years = 105, ≥3 years = 89, ≥5 years = 64.
Numbers for cohorts with age cutoffs: ≥1 year = 288, ≥2 years = 260, ≥3 years = 218, ≥5 years = 163.
Numbers for cohorts with age cutoffs: ≥1 year = 185, ≥2 years = 169, ≥3 years = 147, ≥5 years = 115.
Numbers for cohorts with age cutoffs: ≥1 year = 103, ≥2 years = 91, ≥3 years = 71, ≥5 years = 48.
Features with missing data >10% noted
11–19% missing
20–29% missing.
Abbreviations: CDD, CDKL5 deficiency disorder; CDKL5, cyclin-dependent kinase-like 5; EEG, electroencephalogram.