Prevalence of ADHD in adults declines with age in the general population. We think, however, that the unclear validity of DSM-IV diagnostic criteria for this condition can lead to reduced prevalence rates by underestimation of the prevalence of adult ADHD.

Adult ADHD subjects display significantly poorer functioning versus healthy controls on complex but not on simple tasks of attention, and the degree of impairment varies with gender, with males displaying a higher level of impairment.

Our objective was to conduct a meta-analysis of therapeutic efficacy of pharmacological treatment of adult ADHD based on data from controlled clinical trials. We used the search engines PubMed and Medline to identify relevant clinical trials. Short-term studies with double-blind parallel-group design were selected for the analysis. Altogether, we identified 11 trials that met the criteria, and investigated a total of 1991 subjects, 694 and 1297 of whom were treated with placebo or active medication, respectively. In order to pool efficacy data from studies with different characteristics, including different number of participants, different trial duration and measures of efficacy, the statistical effect sizes for each study had to be calculated. Our findings showed that the pooled effect size across all treatments was in the medium-to-high range (Cohen's d=0.65, p<0.0001 vs. placebo), and the effect size for stimulants (Cohen's d=0.67, p<0.0001 vs. placebo) was somewhat higher than for non-stimulant medications (Cohen's d=0.59, p<0.0001 vs. placebo). The current database of controlled trials for adult ADHD is relatively small, and does not include data for many of the potentially important agents. In addition, effect-size estimates for different classes of medications (i.e. stimulant and non-stimulant medications) were based on separate studies; head-to-head comparisons of various agents are severely lacking. Nonetheless, results of this meta-analysis across all ADHD medications in adult subjects demonstrated statistically significant and clinically robust improvement in symptom severity compared to placebo treatment.

No abstract

The goal of the study was twofold: (1) to investigate the effect of different diagnostic criteria on prevalence estimates of adult attention deficit hyperactivity disorder (ADHD), and (2) to provide prevalence estimates of adult ADHD for the first time in a Hungarian sample. Subjects between 18 and 60 years were included in the screening phase of the study (N = 3,529), conducted in 17 GP practices in Budapest. Adult self-report scale 6-item version was used for screening. Out of 279 positively screened subjects 161 subjects participated in a clinical interview and filled out a self-report questionnaire to confirm the diagnosis. Beside DSM-IV diagnostic criteria, we applied four alternative diagnostic criteria: 'No-onset' (DSM-IV criteria without the specific requirement for onset); full/Sx (DSM-IV "symptoms only" criteria); and reduced/Sx (DSM-IV "symptoms only" criteria with a reduced threshold for symptom count). Crude prevalence estimates adjusted for the specificity and sensitivity data of the screener were 1.35% in the 'DSM-IV' group, 1.64% in the 'No-onset' group, 3.65% in the 'Sx/full' group and 4.16% in the 'Sx/reduced' group. Logistic regression analysis showed that ADHD was significantly more prevalent with younger age and male gender [chi(2) = 14.46; P = 0.0007]. Prevalence estimates corrected for the 'not-interviewed' subsample and adjusted for specificity and sensitivity data of the screener was 2.3% in males, 0.91% in females; 2.02% in the < or =40 years age group and 0.70% in the >40 years age group, based on DSM-IV diagnostic criteria. Prevalence rates found in this study are somewhat lower, but still are in line with those reported in the literature.