HIGH RATE: Adderall pills for ADHD. Women are filling prescriptions for ADHD drugs in growing numbers. Picture: The New York Times

A new report raises questions about the increasing use of a diagnosis that once was reserved for children and adolescents.
Government researchers in the US tracked prescriptions for drugs to treat ADHD, like Adderall and Vyvanse, among women aged 15 to 44 years from 2003 to 2015. The sample included more than 4 million women per year, on average, all of whom had private health insurance with drug coverage.

ADHD prescription rates increased sharply in all age groups during that period, but most steeply among young adult women: by 700% among women aged 25 to 29, and by 560% among women aged 30 to 34.

Between 3% and 6% of adult women in various age groups got these prescriptions in 2015, the researchers found, compared with 1% or less in 2003. The rate rose among women aged 20 to 24, for example, to 5.5% in 2015 from 1% in 2003. The most commonly used ADHD drugs among women were Adderall, Vyvanse and Ritalin, the study found.

The report broke down prescription rates by region, finding the largest increases in southern and western states. Overall rates were sharply higher in the US, compared with previous estimates in the UK or Canada.

This difference “might reflect higher ADHD medication prescribing in the US or differences in the types of ADHD medications” used in these countries, the authors concluded. The findings come as rising prescription rates for psychiatric drugs are receiving increasing scrutiny.

For decades, experts have questioned the increase in ADHD diagnoses among children and adolescents. The rates far outstrip estimated prevalence of the disorder, and the first-line treatment is almost always a prescription for stimulant medication. The new study suggests that the increase has happened among adults, too.

Recent changes in diagnostic guidelines have extended the criteria to adults who have experienced inattentiveness and restlessness since childhood. Psychiatrists generally accept long-standing ADHD as a valid, treatable disorder in adults.

But many also acknowledge that these drugs have wide appeal as performance-enhancers: among students as study aids, and among adults seeking an edge in their work.

Yet prevalence studies, using strict criteria, estimate that around 3% of adult women overall have ADHD, well under the 5% and higher rates recorded in some age groups by the Centers for Disease Control and Prevention.

The new study is also relevant to more recently proposed diagnosis: adult-onset ADHD, in which symptoms emerge out of the blue, well after adolescence. Experts debate whether this diagnosis is valid, and a study concluded that the disorder did not exist.

“If adult symptoms are being reported by patients, it shouldn’t necessarily be immediately classified as ADHD,” said Margaret Sibley, an associate professor of psychiatry and behavioural health at Florida International University, the lead author of that study.

“A more careful evaluation often finds that there’s something else causing the problems, like depression, or drug use - which is what we found.”

The Centers for Disease Control and Prevention report looked only at numbers of prescriptions and not at the types of diagnoses to justify them. The study also raises concerns specific to women, according to Coleen Boyle, director of the Centers for Disease Control and Prevention’s national centre on birth defects and developmental disabilities.

“Half of all pregnancies in the US are unplanned, and women may be taking prescription medicine early in pregnancy before they know they are pregnant,” Boyle said. “Early pregnancy is a critical time for the developing baby. We need to better understand the safest ways to treat ADHD before and during pregnancy.”