Long-term studies evaluating the impact of ADHD treatment into adulthood are limited. The aim of the current study was to determine functional and behavioural long-term outcomes in young adults (aged 13–24 years) who had participated in the Cologne Adaptive Multimodal Treatment (CAMT; Döpfner et al, 2004) study. CAMT used an adaptive treatment approach with variable treatment intensity to simulate clinical practice. Participants received six, 50-minute sessions of psychoeducation followed by ADHD medication plus psychoeducation and/or behaviour therapy.
This 18-year follow-up study of CAMT, was conducted from 2009 through 2014. Seventy (93%) of the 75 participants, who were aged 22‒32 years at the 18-year follow-up (mean [standard deviation, SD] age, 27.3 [2.2] years; 93% male) were contacted by telephone or mail to participate in the study. Using a structured telephone interview psychosocial functioning including educational attainment, occupational status, partnerships, driving and delinquent behaviour; as well as treatment and body mass index (BMI) were assessed. Five participants (7%) could not be reached. Of the 70 participants interviewed, 57 (81%) agreed to complete additional ADHD rating scales and 45 (64%) agreed to participate in clinical face-to-face interviews on ADHD and comorbid symptoms. Rating scales were completed by participants (self-rating), and by parents or significant others (proxy rating).*
The prevalence of ADHD according to Diagnostic and Statistical Manual of Mental Disorders – 5th Edition (DSM-5TM) criteria was determined using the Diagnostic Checklist ADHD for Adults (DCL-ADHS-E). Forty-four of 75 participants (59%) were interviewed. Of these, 12 (27%) were diagnosed with ADHD (predominantly inattentive subtype: n=8, predominantly hyperactive-impulsive subtype: n=2, combined subtype: n=2), and 24 participants (55%) were diagnosed with ADHD in partial remission (predominantly inattentive subtype: n=8, predominantly hyperactive-impulsive subtype: n=3, combined subtype: n=13). Eight of the 44 participants (18%) were not diagnosed with ADHD at the 18-year follow-up assessment. A significant decline in ADHD symptoms was observed at the 18-year follow-up (p < 0.001).
Educational attainment and occupational status
Despite symptomatic improvement, CAMT participants reported poorer educational and occupational outcomes than the general population in Germany. A greater proportion of CAMT participants received a low-level school diploma versus the general population (45% versus 19.5%, relative risk (RR) = 2.3), and a low percentage of CAMT participants received a high-level school diploma compared with the general population in Germany (CAMT: 13%, general population: 45%; RR = 0.3). CAMT participants were also at higher risk of not completing professional training as adults (26% for CAMT participants versus 13% in those aged 20−29 years in the general population [RR = 1.98]). In addition, 52% of CAMT participants had been unemployed in the past, and 25% had been unemployed for ≥12 months.
Comorbid conditions and body mass index
Compared with the general population in Germany, individuals who participated in CAMT, were more likely to have antisocial personality disorder, avoidant personality disorder, paranoid personality disorder or schizoid personality disorder (RR = 6.8, 2.0, 1.3 and 2.0, respectively). Self-reported rates of cigarette smoking, alcohol use and drug use were also higher for CAMT participants versus the general population (RR = 3.4, 1.3 and 5.2, respectively). Of the 63 CAMT participants that provided information on their BMI, 32% reported being overweight (BMI 25.0–29.9, n=20) or 13% reported being obese (BMI ≥30.0, n=8).
Psychological/psychiatric treatment and functional impairment
Seventeen per cent of the 66 participants that provided information on current/past psychological/psychiatric treatment had received medication for mental disorders compared with 5% in men aged 25−35 years (RR = 3.6) and 18% had received outpatient and or inpatient psychological or psychiatric treatment. Acute psychosis and substance abuse were the most common reasons for inpatient treatment (n=4, 65 and n=3, 4.5%). More than 20% of study participants were rated as having a functional impairment with regard to community activities (n=10, 23%), learning/acquiring new learning content (n=9, 21%), finances (n=12, 28%) and daily responsibilities (n=12, 28%).†
Living arrangement, partnerships, driving behaviour and delinquent behaviour
Information on partnership status was available for up to 64 participants depending on the interview item. The majority of CAMT participants reported being in a long-term relationship (52%) and 11% were married. However, 24% reported having frequently changed sexual partners and 30% reported frequently engaging in unsafe sex. Of the 54 participants who provided information on driving behaviour, 61% reported having a driver’s license; 6% of these individuals had caused a car accident involving physical injury and 73% had caused car damage. Furthermore, CAMT participants had higher rates of delinquent behaviour (e.g. lifetime convictions: 33%) than the general population in Germany.
Limitations of the study were that only 81% of the follow-up participants completed rating scales for ADHD and only 64% participated in the clinical interview. Five participants were lost to follow-up which may have influenced the results of the analyses. Reasons for non-participation in the study were not assessed, therefore comparisons between those that participated in the study and those that did not participate could not be made. In addition, the study did not include an untreated control group. Therefore, observed symptom reductions during follow-up could not be attributed to initial treatment effects.
In summary, individuals diagnosed with ADHD during childhood who received adaptive multimodal treatment during their early school years had improved ADHD symptoms at 18-year follow-up. However, individuals who participated in the CAMT study had a higher relative risk of psychosocial impairments, health-related aspects and psychiatric comorbidities. These findings illustrate the importance of providing individualised treatment to support individuals with ADHD throughout the lifespan.
Read more about long-term follow-up of ADHD after multimodal treatment here
*At the 18-year follow-up, the ADHD self-rating scale (Fragebogen zur Erfassung von ADHS im Erwachsenenalter– aktuelle Probleme Fremdbeurteilung [FEA-ASB]) was completed by 55 (73%) participants. Proxy ratings (Fragebogen zur Erfassung von ADHS im Erwachsenenalter– aktuelle Probleme Fremdbeurteilung; FEA-AFB; n = 48, 64%) were completed by mothers (n=30), partners (n=15), grandmothers (n=1), siblings (n=1) or friends (n=1). The scales contained 23 items assessing ADHD symptoms rated on a 4-point Likert scale with ratings ranging from 0 (not at all) to 3 (very much).
†Ratings were given by external raters (n=43) who completed the Impairment subscale of the FEA-AFB/FEA-ASB.
Döpfner M, Mandler J, Breuer D, et al. Children with attention-deficit/hyperactivity disorder grown up: an 18-year follow-up after multimodal treatment. J Atten Disord. 2020; Epub ahead of print.
Döpfner, M, Breuer D, Schürmann S, et al. Effectiveness of an adaptive multimodal treatment in children with attention-deficit hyperactivity disorder – global outcome. Eur Child Adolesc Psychiatry 2004; 13(Suppl 1): I117-I129.