Study reports rising rates of ADHD diagnosis in veterans

Reviewed by Kate Anderton, B.Sc. (Editor)Feb 26 2020

Rates of diagnosed attention deficit-hyperactivity disorder (ADHD) in veterans receiving care in the VA health system more than doubled during the past decade, reports a study in the March issue of Medical Care. The journal is published in the Lippincott portfolio by Wolters Kluwer.

ADHD has been diagnosed in nearly one percent of patients making VA primary care or mental health visits, while the rate of new diagnoses has increased steadily in recent years, according to the research by Andrew C. Hale, PhD, of the VA Center for Clinical Management Research and colleagues at University of Michigan Medical School, Ann Arbor. They write, "Overall increases and demographic differences in adult veterans diagnosed with ADHD suggest a growing need to establish the reliability of diagnostic practices to ensure appropriate and equitable care."

More diagnosed cases of ADHD in veterans, with changing patient characteristics

The researchers analyzed trends in ADHD diagnosed in a national sample of veterans receiving care from 2009 to 2016. During that time, an average of more than five million VA patients were seen at a primary care or mental health clinic each year. The prevalence (overall number of cases) and incidence (number of cases diagnosed per year) of ADHD were analyzed, along with trends in demographic factors and concomitant mental health issues.

The number of VA patients diagnosed with ADHD increased from approximately 6,500 in 2009 to 30,000 in 2016, for a total of more than 96,000 new cases. With adjustment for age, the annual prevalence of ADHD increased from 0.23 to 0.84 percent. The incidence of ADHD increased from 0.14 to 0.48 percent.

"The age-adjusted prevalence of ADHD in a sample of veterans using primary care or mental health clinic services more than doubled over the eight-year period from [2009 to 2016]," Dr. Hale and coauthors write. They note that the figures are similar to increases in population trends in US youths and adults during the same period.

The increases in ADHD were lowest for black veterans and older veterans. However, rates of ADHD diagnosis increased in all demographic subgroups. The prevalence of ADHD was highest - over four percent in 2016 - in veterans aged 18 to 29 years. Both prevalence and incidence of ADHD were greater in women compared to men.

Although numbers of accompanying mental health diagnoses associated with ADHD remained about the same, the patterns of these conditions changed - including an increase in post-traumatic stress disorder (PTSD). Despite the rising rates of ADHD diagnosis, the proportion of veterans with neuropsychological evaluations within six months of a new diagnosis decreased from 12.6 to 10.8 percent.

While the prevalence of ADHD in US children is known to have increased, trends in ADHD diagnosis among adults are unclear. In adults, ADHD is linked to increased rates of psychiatric disorders along with problems with relationship and at work or in school. Based on data in active-duty service members, veterans might be at increased risk of ADHD.

The new study shows significant increases in rates of diagnosed ADHD among veterans in the VA health system over the past decade. Dr. Hale and colleagues suggest that several factors may have contributed to these trends, including changing diagnostic criteria, changes in the characteristics of the VA patient population, and increases in conditions that may have overlapping symptoms with ADHD, such as PTSD and traumatic brain injury.

Although diagnoses of ADHD in the VA system have increased across the board, some groups have higher rates, such as younger veterans and women; while others have lower rates, including black veterans. The shifting trends in associated mental health issues raises concerns as to whether these problems are being accurately recognized and treated.

Dr. Hale and colleagues conclude:

Systematic approaches to screening and evaluation, including potentially greater use of neuropsychological evaluations, should be explored to improve the reliability of diagnostic practices across patient subgroups and over time and to ensure appropriate treatment."