Dramatically reduced life expectancy for those diagnosed with ADHD

Attention-Deficit/Hyperactivity Disorder (ADHD) is a mental health disorder characterized by a persistent pattern of inattention, hyperactivity, and impulsivity that interferes with daily functioning and development. It's one of the most common mental disorders affecting children, but can also continue into adulthood. The exact cause of ADHD is not fully understood, but research suggests a combination of genetic, neurological, and environmental factors play a role.

The deficiencies in executive functions seen in individuals with ADHD lead to challenges in remaining structured, managing time effectively, avoiding chronic procrastination, retaining focus, sustaining attention, warding off distractions, controlling emotions, and recalling particulars. 

Generally speaking, there are three types of ADHD: 1) inattentive, 2) hyperactive-impulsive, and 3) combined. The most common type is the combined with subjects manifesting both inattention and hyperactivity-impulsivity.

As mentioned above, ADHD is a relatively common disorder. It is estimated to affect around 5-7% of school-aged children worldwide, and around 2.5-3% of adults. However, many adults with ADHD may be undiagnosed, especially if their symptoms are predominantly inattentive. ADHD is diagnosed more frequently in boys than in girls, particularly in childhood. However, this may be partly due to differences in how symptoms present. Girls are more likely to have inattentive-type ADHD, which can be less obvious.

Individuals with ADHD may experience a range of challenges, including:

• Academic difficulties and lower educational attainment.
• Occupational problems, including job instability and lower income.
• Increased risk of mental health disorders, such as anxiety and depression.
• Higher rates of substance use and addiction.
• Relationship problems.
• Increased risk of accidents and injuries.
• Increased risk of premature death due to various factors.

Early diagnosis and treatment can improve outcomes: With appropriate management, individuals with ADHD can lead successful and fulfilling lives. Unfortunately many are not diagnosed early enough or treated effectively. Previous studies have found evidence of increased early deaths for people with ADHD, with a 2022 meta-analysis reporting deaths from unnatural causes (e.g. accidents, suicides) to be 2.81 times higher among those diagnosed with ADHD.

Recently published research examined death from all causes (not just unnatural) to estimate life expectancy specifically in people diagnosed with ADHD. The authors examined 9,561,450 patients in Britain's National Health Service (NHS), identifying 30,039 adults (aged 18+) with ADHD. Each person with ADHD was matched with 10 peers without the disorder for comparison (i.e. 300,390 individuals in comparison group) with the study period lasting from 2000-2019.

Life expectancy was estimated using life tables. A life table follows a cohort from birth until all members have died counting the number of deaths in a specific age interval (e.g., 5-9 years) per 1,000 individuals in that age group. From these data, one can calculate age-specific death rates and life expectancy.

The results were striking: males with ADHD had 6.78 years shorter life expectancy, and females with ADHD had 8.64 years shorter life expectancy compared to the control group (Figure 1).

What is the explanation for this reduced life expectancy in those diagnosed with ADHD? Unfortunately in the study, there was no information on the cause of death. However, the previous study mentioned above described the increased number of deaths from unnatural causes. In addition, multiple papers have noted the challenges from ADHD listed above can lead to behaviors such as substance abuse, smoking, excess risk taking, and compulsive behavior that increase the probability of early death. This includes not taking care of one's health and well-being in a general sense. One Swedish study found that adults with ADHD exhibited a two-fold higher risk of cardiovascular disease.

One caveat is that because ADHD is underdiagnosed, many of those participating int he study may be more severely affected drawing attention from the health system leading to an earlier diagnosis. Thus, including those undiagnosed with ADHD and presumably with less severe symptoms, may reduce the extent of the decrease in life expectancy. 

In summary, the findings highlight the need for improved diagnosis, support, and treatment for adults with ADHD to address the life expectancy deficit and improve their overall health outcomes. The authors concluded:

“Adults with diagnosed ADHD are living shorter lives than they should. We believe that this is likely caused by modifiable risk factors and unmet support and treatment needs in terms of both ADHD and co-occurring mental and physical health conditions. This study included data from adults with diagnosed ADHD; the results may not generalise to the entire population of adults with ADHD, the vast majority of whom are undiagnosed.”

Life expectancy was calculated from the mortality curves (O'Nions et al. BJPsych. 2025). The largest difference between ADHD group and control group was during middle age.