Abstract
Aim: To investigate the possible use of different neuropsychological
tests for diagnosis of adult patients with Attention Deficit
Hyperactivity Disorder (ADHD), with specific reference to memory tests.
Methods: Patients were referred from psychiatric out-patient units as
part of routine clinical assessment. 158 adults were diagnosed with
DSM-IV-TR, median age 32 years. A clinical interview was conducted
together with four self-report questionnaires. The patients were
neuropsychologically assessed before possible treatment, and were
followed-up three years later. A group of 13 standard neuropsychological
tests and a dichotic memory test were administered. At telephone
follow-up three years later, the patients were interviewed with ASRS v1.1
to assess their ADHD symptoms, and some new questions were posed about functional impairment.
Results: A significant reduction was found in memory tests, including
dichotic memory, in the study group after analysis for the covariance
(ANCOVA) effects of IQ, sex, age, and years of education; the effects of
depression and anxiety on the HAD scale had been removed. Profound
reduction was found on the working memory capacity tests with
distracters: the Consonant Trigram test, the Dichotic Memory test and the
Benton VRT. Reductions were also found in learning and delayed recall on
the Rey Auditory Verbal Learning test and the modified Diagnosticum für
Cerebralschädigung. Minor but significant reductions were found on Digit
Span Backward (WAIS), Arithmetic Capacity (WAIS), Raven SET I, WCST
Number of Perseverations and in the Trail Making B test, compared with
controls. At follow-up, an ADHD medicated group showed a significant
reduction in their symptoms compared with non-medicated patients, and
also better self-confidence. The rate of employment was low; in total, 58
% were without employment, even after medication.
Conclusions: In adult patients with ADHD, neuropsychological testing
using working memory capacity tests with distracters, demonstrate a
reduced working memory capacity. In a follow-up, patients on medication
showed fewer symptoms and better self-confidence, but many continued to be unemployed.