Chapter 01 – Introduction
Age is a risk factor for developing cognitive dysfunction. The prevalence of dementia in some studies is about 1% in 65- to 69-year-olds compared with 41% in those aged 90 and over. The presence of dementia or cognitive dysfunction can seriously impact cancer care and treatment. It is important to keep in mind that in some cases formal cognitive testing is the only way to identify cognitive dysfunction, especially in early stages of disease when the patient has preserved language function or if the caregiver does most of the talking.
Pre-treatment counselling often involves complicated decision-making, involving weighing the cost and benefit of different treatment options, and it is paramount for the counselling physician to assess the patient´s decision-making capacity.
For surgical procedures, the risk of post-operative acute confusional state (known as delirium) is markedly increased in the presence of preoperative cognitive dysfunction. Delirium can be prevented, as described below. When a patient is treated with chemotherapy, cognitive dysfunction warrants concern regarding the patient’s understanding of important signs of toxicity, such as fever or bleeding, and arranging more intensive surveillance may be necessary. As both surgery under general anaesthesia and chemotherapy treatment may alter cognitive function, it is important to consider whether the treatment places the patient at risk for being transferred from an independent to a dependent life situation.