What dementia means

Dementia describes a group of symptoms caused by diseases that affect the brain. It is not one condition, and it is not a normal part of ageing. Changes usually develop over time, but every person's experience is different.

You do not need to work out which type of dementia someone has. Diagnosis belongs to their doctor and specialist team. It helps to know the main types at a high level, because they can shape what you notice.

• Alzheimer's disease is the most common type. Difficulty remembering recent events is often an early sign.
• Vascular dementia is linked to changes in the brain's blood supply. The pattern of change can vary depending on which areas are affected.
• Lewy body dementia can involve changes in alertness and attention from hour to hour, and may involve vivid visual experiences or movement changes.
• Frontotemporal dementia often affects behaviour, personality or language first, and can begin at a younger age.

Dementia can affect thinking and memory, the ability to find words or follow a conversation, mood and emotions, and the skills needed for daily tasks. These changes can be tiring and frightening for the person, and for the people who love them.

Identity is not erased. A person still has a life story, values, preferences, relationships and feelings. Emotional connection often stays strong, and so can responses to music, touch, routine and familiar faces. Your role is to notice strengths as well as needs.

• Thinking and memory: recent events, planning, orientation to time and place.
• Communication: finding words, following long sentences, understanding quickly changing topics.
• Emotions: anxiety, low mood, frustration, or feeling flat.
• Everyday function: cooking, dressing, managing money or medication, finding the way.

A sudden change in a person's thinking, alertness or behaviour may point to something that needs urgent attention. Delirium is a sudden, often fluctuating change in attention and awareness, and it is a medical concern that needs assessment.

Possible contributors include infection, pain, dehydration, constipation, the effects of medicines, or another acute illness. You are not expected to work out the cause. You are expected to notice, describe what you see, and tell the right person quickly.

• Compare with the person's usual self: 'more sleepy than yesterday' is more useful than 'confused'.
• Describe what you saw and when, using plain and objective words.
• Report following your workplace escalation process. If someone appears seriously unwell, follow your emergency procedure and call 000.
• Avoid diagnostic assumptions. Say what you observed, not what you think it is.