Normal ageing or early dementia? How doctors tell the difference
Highlights
Age-related changes are often harmless.
Dementia is a general term for conditions that affect memory, thinking, behaviour and a person’s ability to independently carry out routine activities.
There is also a middle ground known as mild cognitive impairment (MCI), where memory or thinking problems are greater than expected for age.
As people grow older, it is natural to ask, “Where did I keep my glasses?” “What was her name?” or “When is my next doctor's visit?" Forgetting where you kept your keys, missing a bill payment, struggling to recall someone’s name, or occasionally walking into a room and forgetting why you went there are common experiences as we age. This raises an important question: “Is this normal ageing, or could it be an early sign of dementia or Alzheimer’s disease (AD)?” This article explains the difference between normal age-related forgetfulness and early dementia, when memory changes may need medical attention, and what the next best action is.
Age-related changes are often harmless. Occasionally forgetting something but remembering it later, or taking longer to learn something new, can be part of normal ageing. However, when memory or thinking problems become frequent, progressively worsen and interfere with everyday life, they may be signs of early dementia. Dementia is a general term for conditions that affect memory, thinking, behaviour and a person’s ability to independently carry out routine activities they could previously manage.
Signs of early dementia may include repeatedly asking the same questions, forgetting recent conversations, getting lost in familiar places, struggling to manage finance or medicines, or finding familiar tasks increasingly difficult. Changes may also involve difficulties with language, problem-solving, judgement, attention, behaviour or personality. There is also a middle ground known as mild cognitive impairment (MCI), where memory or thinking problems are greater than expected for age. However, everyday activities can usually still be managed independently. MCI does not necessarily progress to dementia. Importantly, cognitive difficulties can also result from depression, poor sleep, medications, nutritional deficiencies, thyroid or vascular problems, and other medical or neurological conditions. So, what should you do next? There is no need to panic. Early medical evaluation helps distinguish normal ageing from MCI, AD, or other potentially treatable causes.
Evaluating cognitive changes usually involves a combination of clinical assessment, laboratory testing and brain imaging. Doctors will first discuss when the changes began, whether they are worsening, and how they are affecting everyday life (work, household responsibilities, finances, and social activities), sometimes seeking additional information from family members, particularly when the patient is unable to recognise these changes. This is followed by physical and neurological examination and brief cognitive tests assessing areas like memory, attention, language, orientation, and problem-solving. Depending on the person’s symptoms and medical history, laboratory tests and brain imaging, such as an MRI or CT scan, may be advised to identify the underlying cause and reach an appropriate diagnosis.
Pathology laboratories are becoming an increasingly important part of this diagnostic journey. Laboratory investigations do not simply test for dementia; they can help identify potentially treatable medical conditions that may cause or contribute to memory and thinking problems. Routine investigations may include blood counts, thyroid function tests, vitamin levels, and other relevant biochemical markers depending upon the patient’s history and clinical findings. Tests help identify conditions like hormonal or nutritional deficiencies, medication-related effects, or other illnesses that may contribute to cognitive symptoms.