Does ADHD Become Less Common as People Age?

What you need to know

• The prevalence of ADHD decreases across adulthood, from about 15% in young adults to 4% in adults over 60.
• Different definitions of ADHD (symptomatic, persistent, and with impairment) show similar declining trends with age.
• Despite lower prevalence in older adults, ADHD remains severely underrecognized and undertreated in this age group.

Understanding ADHD across the lifespan

Attention-Deficit/Hyperactivity Disorder (ADHD) is a condition that affects both children and adults. It’s characterized by problems with attention, hyperactivity, and impulsivity. While ADHD is well-studied in children, there’s been less research on how it affects adults, especially as they get older.

For a long time, researchers and clinicians have known that ADHD symptoms often become less severe as children grow into adolescents and young adults. However, it wasn’t clear if this trend continued throughout adulthood. Do older adults experience ADHD less frequently than younger adults? Or are we simply not recognizing ADHD in older populations?

A global look at adult ADHD

A recent study by Song et al. tried to answer these questions by analyzing data from 40 different studies worldwide. They found that ADHD does indeed become less common as people age. However, their analysis had some limitations due to differences in how each study defined and measured ADHD.

A new study confirms the trend

To address these limitations, researchers Melissa Vos and Catharina A Hartman conducted a new study using data from over 35,000 adults in the Netherlands. Their findings, published in the Journal of Global Health, strongly support the results of the earlier global analysis.

How ADHD was measured

The researchers used a questionnaire that asked about ADHD symptoms experienced in the past six months. They looked at ADHD in three different ways:

1. Symptomatic ADHD: Having at least five symptoms of inattention or hyperactivity-impulsivity.
2. Persistent ADHD: Having symptoms plus reporting that these issues started before age 18.
3. Persistent ADHD with impairment: Having symptoms, early onset, and significant difficulties in daily life due to these symptoms.

The declining trend of ADHD in adulthood

The study found a clear pattern: ADHD becomes less common as people get older. Here are some key findings:

• Among young adults (18-24 years old):

  • 15.5% had symptomatic ADHD
  • 15.4% had persistent ADHD
  • 8.1% had persistent ADHD with impairment

• Among older adults (60+ years old):

  • 4.3% had symptomatic ADHD
  • 2.8% had persistent ADHD
  • 1.1% had persistent ADHD with impairment

• Overall (across all adult age groups):

  • 8.1% had symptomatic ADHD
  • 6.5% had persistent ADHD
  • 3.4% had persistent ADHD with impairment

These numbers show a consistent decrease in ADHD prevalence as age increases, regardless of how ADHD is defined.

Understanding the decline

The researchers found that the decrease in ADHD prevalence was more pronounced when considering persistent ADHD (symptoms starting before age 18) compared to just looking at current symptoms. This suggests that some of the ADHD-like symptoms in older adults might be due to other factors related to aging, rather than lifelong ADHD.

Adding the impairment criterion (significant difficulties in daily life) further reduced the prevalence across all age groups. This highlights the importance of considering how symptoms impact a person’s life when diagnosing ADHD, not just the presence of symptoms alone.

Why this matters

Understanding how ADHD changes across the lifespan is crucial for several reasons:

1. Improved diagnosis: Knowing that ADHD can persist into older adulthood, even if less common, can help healthcare providers better recognize and diagnose the condition in older patients.

2. Appropriate treatment: Different age groups might need different approaches to managing ADHD symptoms. This research can inform treatment strategies for adults of all ages.

3. Addressing underdiagnosis: Despite the lower prevalence in older adults, ADHD remains severely underrecognized and undertreated in this age group. This study highlights the need for increased awareness and better screening in older populations.

4. Life planning: For individuals with ADHD, understanding how the condition might change over time can help with long-term life planning and managing expectations.

5. Research directions: This study points to the need for more research on ADHD in older adults, including why prevalence decreases and how symptoms might manifest differently in later life.

Limitations and future research

While this study provides valuable insights, it’s important to note some limitations. The data comes from a single region in the Netherlands, so the findings might not apply equally to all populations worldwide. Additionally, the study relied on self-reported symptoms, which can be subject to bias or inaccurate recall, especially when asking older adults about childhood symptoms.

Future research could benefit from:

• Longitudinal studies that follow the same individuals over many years to track changes in ADHD symptoms
• Including objective measures of ADHD symptoms alongside self-reports
• Investigating how ADHD symptoms might manifest differently in older adults compared to younger people
• Exploring the reasons behind the decrease in ADHD prevalence with age (e.g., developmental changes, coping strategies, environmental factors)

Conclusions

• ADHD prevalence decreases across adulthood, with about 15% of young adults and 4% of older adults experiencing symptoms.
• This declining trend is consistent across different definitions of ADHD, including when considering persistent symptoms and impairment.
• Despite lower prevalence in older age groups, ADHD remains underrecognized and undertreated in older adults, highlighting the need for improved awareness and screening.