A 4-Year Follow-Up Study of Attention-Deficit Hyperactivity Symptoms, Comorbidities, and Psychostimulant Use in a Brazilian Sample of Children and Adolescents with Attention-Deficit/Hyperactivity Disorder.

The aim of this study was to evaluate symptom persistence in attention-deficit/hyperactivity disorder (ADHD), the development of comorbidities, and psychostimulant usage patterns. Follow-up studies were conducted in 37 patients with ADHD and 22 healthy controls, aged 10 and 18, 4 years after their first assessment. The ADHD was rated as persistent if participants met all DSM-IV criteria for syndromic or sub-threshold persistence, or had functional impairments (functional persistence). Of the 37 ADHD patients we reevaluated, 75% had persistent symptoms, and psychiatric comorbidities with additional functional impairments and academic problems were more common than in controls. These follow-up findings show a high comorbidity associated with ADHD and support the importance of evaluation and treatment for ADHD and comorbidities throughout life.

The response to stress in Brazilian children and adolescents with attention deficit hyperactivity disorder.

This study assessed the function of the hypothalamic-pituitary-adrenal (HPA) axis, during response to stress, through the measurement of salivary cortisol in 38 children with attention deficit hyperactivity disorder (ADHD) and its subtypes, who were matched to 38 healthy control subjects. These measures were made at four time intervals: 15 min before exposing the subjects to a stressor - the Continuous Performance Test (CPT) - and 20, 40, and 60 min after such exposure. The baseline cortisol levels were statistically similar in both groups. The mean values of cortisol at the four time intervals were not statistically different between the three subtypes of ADHD (inattentive, hyperactive-impulsive and combined); thus, the ADHD group was treated as a single group. Following the stressor test, the ADHD group had significantly higher levels of salivary cortisol than the control group at time intervals of 20 and 40 min, whereas in this latter group exposure to the CPT did not induce an increase of cortisol. These results suggest that the increased cortisol levels in the ADHD group could be due to the lack of comorbidities. In addition, these patients, when facing a computerized test, might have responded with a motivational pathway with an increase of cortisol.