ADHD and Alzheimer’s: understanding the difference

Both can involve forgetfulness, poor concentration or difficulty organising tasks, so the pattern over time matters more than any single symptom. ADHD does not turn into Alzheimer’s, and attention problems alone cannot establish either diagnosis.

With ADHD, a person can often trace distractibility, impulsivity or disorganisation back to childhood, even if these difficulties were recognised only in adulthood. Symptoms may vary with workload, structure, sleep and stress. Alzheimer’s more often brings a new and gradually worsening change from the person’s previous abilities, including trouble retaining recent information, finding words, navigating familiar places or managing familiar tasks.

Sleep problems, anxiety, depression, medication effects, thyroid disorders and other health issues can also affect concentration or memory. A clinician therefore looks beyond the symptom itself and considers onset, progression, daily function and possible alternative explanations.

Arrange a medical appointment if changes persist, interfere with work or home life, or are noticed by someone close to you. Write down when the problem began, whether it is worsening, examples of affected tasks, sleep patterns, mood changes, medical conditions, and all medicines or supplements. If possible, bring someone who knows your usual abilities.

Assessment may include a detailed history, questions about childhood and current functioning, brief thinking or memory tasks, a physical examination, and tests for treatable contributors. The clinician may recommend a mental health, neurological or memory-service assessment depending on the pattern.

Call local emergency services for sudden confusion or a sudden change in speech, vision, balance, strength or sensation, especially weakness or numbness on one side. These abrupt symptoms require emergency assessment and should not be assumed to come from ADHD or Alzheimer’s.

Seek prompt medical help after a head injury if confusion develops, or if the person cannot be awakened, has a seizure, repeatedly vomits or develops worsening headache. For gradual but continuing memory or thinking changes, book a routine appointment soon rather than waiting for daily function to deteriorate further.

Ask which features fit a long-standing attention pattern and which suggest a new cognitive change. You can also ask whether sleep, mood, medicines or another medical condition might contribute; what testing is appropriate; and which changes should trigger urgent reassessment.