Table 2.
Psychiatric Characteristics of the Sample Overall and Split Based on Iron Statusa
| Total sample n=115 | Iron-deficient n=16 | Iron-deplete n=52 | Iron-replete n=47 | Statistic | p value | |
|---|---|---|---|---|---|---|
| Psychopathology | ||||||
| Attention-deficit/hyperactivity disorder (ADHD), n (%) | 106 (92) | 14 (88) | 47 (90) | 45 (96) | Fisher's exact | >0.3 |
| Disruptive behavior disorder, n (%) | 106 (92) | 13 (81) | 48 (92) | 45 (96) | Fisher's exact | >0.1 |
| Anxiety disorder, n (%) | 31 (27) | 5 (31) | 14 (27) | 12 (26) | Fisher's exact | >0.9 |
| Tic disorder, n (%) | 23 (20) | 2 (13) | 11 (21) | 10 (21) | Fisher's exact | >0.8 |
| Pervasive developmental disorder, n (%) | 14 (12) | 1 (6) | 7 (13) | 6 (13) | Fisher's exact | >0.8 |
| Depressive disorder, n (%) | 10 (9) | 4 (25) | 4 (8) | 2 (4) | Fisher's exact | <0.05 |
| Psychosis, n (%) | 1 (1) | 1 (6) | 0 | 0 | Fisher's exact | >0.1 |
| Child Behavior Checklist (n=50), T scores | ||||||
| Anxious/Depressed | 64.2 (11.1) | 59.3 (3.9) | 67.2 (2.5) | 63.6 (2.3) | F=1.54 | >0.2 |
| Withdrawn/Depressed | 62.7 (8.4) | 60.9 (2.9) | 66.1 (1.9)* | 60.4 (1.7)* | F=2.77 | <0.08 |
| Somatic complaints | 58.9 (7.8) | 56.4 (2.8) | 59.2 (1.8) | 59.5 (1.7) | F=0.49 | >0.6 |
| Social problems | 66.6 (9.0) | 61.1 (3.1)* | 69.9 (2.0)* | 65.7 (1.8) | F=3.17 | <0.06 |
| Thought problems | 68.1 (8.8) | 69.6 (3.1) | 69.2 (2.0) | 66.6 (1.9) | F=0.59 | >0.5 |
| Attention problems | 69.2 (10.2) | 74.9 (3.6) | 67.7 (2.3) | 68.3 (2.1) | F=1.54 | >0.2 |
| Rule-breaking behavior | 64.4 (7.9) | 63.8 (2.9) | 63.8 (1.9) | 65.0 (1.7) | F=0.13 | >0.8 |
| Aggressive behavior | 71.0 (12.1) | 67.6 (4.3) | 73.4 (2.8) | 70.3 (2.5) | F=0.71 | >0.4 |
| Internalizing problems | 60. (9.0) | 60.3 (3.1) | 66.6 (2.0) | 62.1 (1.8) | F=1.97 | >0.1 |
| Externalizing problems | 67.7 (9.7) | 66.4 (3.5) | 68.9 (2.3) | 67.2 (2.0) | F=0.25 | >0.7 |
| Total problems | 69.0 (7.8) | 67.9 (2.8) | 70.5 (1.8) | 68.1 (1.6) | F=0.57 | >0.5 |
| Psychopharmacology | ||||||
| Risperidone dose, mg/kg/day, mean (SD) | 0.03 (0.02) | 0.03 (0.01) | 0.03 (0.00) | 0.04 (0.00) | F=1.15 | >0.3 |
| Serum concentration, ng/mL, mean (SD) | 10.6 (11.7) | 10.0 (2.9) | 9.4 (1.6) | 12.2 (1.7) | F=0.76 | >0.4 |
| Treatment duration, years, mean (SD) | 2.4 (1.7) | 2.2 (0.4) | 2.7 (0.2) | 2.2 (0.2) | F=0.94 | >0.3 |
| Psychostimulants, n (%) | 85 (74) | 12 (75) | 39 (75) | 34 (72) | Fisher's exact | >0.9 |
| Psychostimulants dose, mg/kg/day, mean (SD) | 1.4 (0.8) | 1.3 (0.2) | 1.3 (0.1) | 1.6 (0.1) | F=1.26 | >0.2 |
| Treatment duration, years, mean (SD) | 5.3 (2.6) | 4.8 (0.8) | 5.5 (0.4) | 5.2 (0.5) | F=0.31 | >0.7 |
| Serotonin reuptake inhibitor (SSRIs), n (%) | 52 (45) | 7 (44) | 23 (44) | 22 (47) | Fisher's exact | >0.9 |
| α2-agonists, n (%)b | 37 (32) | 1 (6) | 17 (33) | 19 (40) | Fisher's Exact | <0.04 |
| Multivitamin use, n (%) | 36 (31) | 4 (25) | 11 (21) | 21 (45) | Fisher's Exact | <0.04 |
Statistically significant results (p<0.05) are bolded and those suggestive of an association (p<0.1) are bolded and italicized. For continuous variables, means (SD) are reported for the total sample and means (SE) are reported for the three “iron status” groups.
a
Iron status was defined based on a combination of serum ferritin and transferrin receptor concentration (see Methods) (World Health Organization 2011).
b
These include guanfacine and clonidine frequently used to treat ADHD, insomnia, and disruptive behavior.
*
p<0.10.