In older adults, lifelong differences associated with neurodivergence such as difficulties with attention, organisation, planning or forgetfulness are often mistaken for normal ageing, depression or dementia, delaying diagnosis and treatment. Experts say recognising that conditions such as Attention-deficit/hyperactivity disorder (ADHD) can persist throughout life is essential to identifying people who have remained undiagnosed for years.

Missed diagnosis

ADHD is a neurodevelopmental disorder that begins in childhood but often persists throughout life. According to the World Health Organization (WHO), it is characterised by persistent patterns of inattention and/or hyperactivity-impulsivity that interfere with functioning or development. While symptoms typically emerge in childhood, they can continue into adolescence and adulthood, affecting education, employment, relationships and everyday life.

Despite this, ADHD continues to be viewed largely as a childhood condition. As a result, many of today’s older adults grew up at a time when awareness of the disorder was limited and children with inattentive symptoms were rarely evaluated. Instead, behaviours such as losing things, forgetting instructions, struggling to stay organised or appearing distracted were often dismissed as carelessness, laziness or poor discipline, says Vivian Kapil, consultant psychiatrist, SRM Prime Hospital.

Not everyone with ADHD presents with hyperactive behaviour. People with predominantly inattentive symptoms, particularly those who performed reasonably well academically or developed effective coping strategies, were less likely to come to clinical attention, says Sabaresh Pandiyan, consultant psychiatrist, Rela Hospital. Family members often unknowingly compensated by creating routines, reminders and checklists that helped manage daily life.

Nithya M., consultant psychiatrist, Apollo Speciality Hospitals, Vanagaram, Chennai, says many people also develop lifelong coping strategies that mask symptoms. A structured job, written reminders or support from a spouse may help them function well for years. However, retirement or the loss of a spouse can remove that external structure, allowing long-standing attention and organisational difficulties to become more apparent.

Over time, symptoms also change. Hyperactivity may become less prominent, while difficulties with planning, organisation, prioritising tasks, time management and sustaining attention become more noticeable. Mithun Prasad, consultant, psychiatry, SIMS Hospital, says retirement or the loss of structured routines can expose challenges that had remained hidden for decades. In some families, an older adult seeks evaluation only after recognising similar lifelong patterns following a grandchild’s ADHD diagnosis.

ADHD mistaken for ageing

Diagnosing ADHD later in life is not straightforward because many of its symptoms overlap with normal ageing and conditions such as depression, anxiety and dementia. Forgetfulness, poor concentration and disorganisation are common complaints among older adults. However, psychiatrists say the distinguishing feature is not the symptom itself, but when it first appeared.

“The most important clue is the lifelong pattern,” says Dr. Prasad. ADHD begins in childhood and remains relatively stable over the years, whereas dementia is characterised by a progressive decline that develops later in life.

Making the diagnosis therefore requires far more than a memory assessment. Clinicians need to obtain a detailed developmental history, understand how symptoms affected school, work and relationships over the years, and, wherever possible, gather information from family members.

Lakshmanan S., consultant neurologist at Kauvery Hospital, Chennai, points out that current screening tools have largely been validated in children and younger adults, leaving a gap in age-appropriate assessment for older people.

The health impacts

Experts say untreated ADHD can shape many aspects of a person’s life long before a diagnosis is made.

Persistent difficulties with organisation, planning and time management may limit educational attainment and career progression despite an individual’s abilities. Impulsivity and emotional dysregulation can affect relationships and financial decision-making, while forgetfulness may interfere with managing medicines, attending appointments and maintaining healthy routines.

Research has also shown that ADHD frequently coexists with depression, anxiety disorders, substance use disorders and obesity. Dr. Lakshmanan says repeated experiences of being labelled careless or undisciplined often contribute to chronic stress, low self-esteem and feelings of underachievement over many years.

Receiving a diagnosis later in life can therefore be significant. Many people finally gain an explanation for patterns that have affected them since childhood, says Dr. Prasad.

Treatment strategies

Treatment for ADHD in older adults is tailored to the individual and depends on symptom severity, functional impairment and other medical conditions.

An important first step is psychoeducation, which helps patients and their families understand that ADHD is a neurodevelopmental condition rather than a lack of motivation or discipline, says Dr. Kapil.

Both stimulant medications, such as methylphenidate and dexamphetamine, and non-stimulant medicines including atomoxetine are effective treatment options. However, older adults are more likely to have cardiovascular disease, hypertension or other chronic illnesses and may already be taking multiple medications. Dr. Lakshmanan says clinicians should assess cardiovascular health and potential drug interactions before prescribing medication and continue to monitor patients closely. Dr. Nithya says treatment should begin cautiously, with lower doses and gradual adjustments while monitoring for side effects and managing coexisting conditions such as depression, anxiety, diabetes and hypertension.

Medication alone is rarely sufficient. Cognitive behavioural therapy can help people develop strategies to improve organisation, time management, planning, emotional regulation and reduce procrastination. Regular physical activity, adequate sleep, structured daily routines, reminders, planners and minimising distractions can also improve day-to-day functioning.

Family support is equally important. Educating caregivers about ADHD helps reduce misunderstanding and blame while creating an environment that supports independence and adherence to treatment. .

Better awareness

Experts say recognising ADHD across the lifespan will require changes in both awareness and clinical practice.

Primary care physicians, psychiatrists, neurologists, psychologists and geriatric specialists need greater training to recognise that ADHD does not end in childhood. Older adults presenting with persistent attention, executive functioning difficulties, chronic procrastination or disorganisation should be asked whether these problems have existed since childhood rather than being assumed to have age-related cognitive decline.