Rates of diagnosed attention-deficit hyperactivity disorder (ADHD) may be increasing in the UK.

Estimate incidence and prevalence of ADHD diagnoses and ADHD prescriptions in UK adults and children in primary care.

We conducted a cohort study using IQVIA Medical Research Data, a UK primary care database. Rates of ADHD diagnoses and ADHD prescriptions were calculated between 2000 and 2018 for individuals aged 3–99 years, analysed by age, gender, social deprivation status and calendar year.

Of 7 655 931 individuals, 35 877 (0.5%) had ADHD diagnoses; 18 518 (0.2%) received ADHD medication prescriptions. Diagnoses and prescription rates were greater in men versus women, children versus adults, and deprivation status (nearly double in most deprived versus least deprived quintile). By 2018, the proportion of ADHD diagnoses was 255 per 10 000 (95% CI 247–263) in boys and 67.7 per 10 000 (95% CI 63.5–71.9) in girls; for adults, it was 74.3 per 10 000 (95% CI 72.3–76.2) in men and 20 per 10 000 (95%CI 19.0–21.0) in women. Corresponding figures for prescriptions were 156 per 10 000 (95% CI 150–163) in boys, 36.8 per 10 000 (95% CI 33.8–40.0) in girls, 13.3 per 10 000 (95% CI 12.5–14.1) in men and 4.5 per 10 000 (95% CI 4.1–5.0) in women. Except among 3- to 5-year-olds, the incidence and prevalence of ADHD diagnoses and prescriptions have increased from 2000 to 2018 in all age groups. The absolute increase was highest in children, but the relative increase was largest among adults (e.g. among men aged 18–29 years, approximately 20-fold and nearly 50-fold increases in diagnoses and prescriptions, respectively).

The incidence and prevalence of both ADHD diagnoses and medication are highest among children. Proportionally, rates increased most among adults during 2000–2018. ADHD diagnoses and prescriptions are associated with socioeconomic deprivation.

Currently, our understanding remains limited of how co-occurring bipolar disorder and attention deficit hyperactivity disorder (ADHD) should be treated.

To evaluate the impact of central stimulant treatment on self-injurious behaviour in patients with a dual diagnosis of bipolar disorder or schizoaffective disorder and ADHD.

Retrospective cohort study (LiSIE) into effects and side-effects of lithium as compared to other mood stabilisers. Here, using a mirror-image design, we compared suicide attempts and non-suicidal self-injury events within 6 months and 2 years before and after central stimulant treatment start.

Of 1564 eligible patients, 206 patients met inclusion criteria; having a dual diagnosis of bipolar disorder or schizoaffective disorder and ADHD at first central stimulant initiation. In these, suicide attempts and non-suicidal self-injury events decreased significantly within both 6 months (p = 0.004) and 2 years (p = 0.028) after central stimulant start. After multiple adjustments, this effect was preserved 2 years after central stimulant start (OR 0.63, 95% CI; 0.40 – 0.98, p = 0.041).

Central stimulant treatment may reduce the risk of self-injurious behavior in patients with a dual diagnosis of bipolar disorder or schizoaffective disorder and ADHD. However, to reduce the risk of manic switches, concomitant mood stabilising treatment remains warranted.

Michael Ott has been a scientific advisory board member of Astra Zeneca Sweden, Ursula Werneke has received funding for educational activities on behalf of Norrbotten Region (Masterclass Psychiatry Programme 2014–2018 and EAPM 2016, Luleå, Sweden): Astra