Background Use of advance directives is increasing as a way for people to exert their autonomy and influence future decisions about their treatment should they lose capacity. In particular advance directives are thought to be useful for those who develop dementia. However, advance directives focus solely on interests prior to the development of dementia and fail to take into account later interests of the patient with dementia.

Aim To explore the limitations of advance directives for those with dementia.

Methods Review of literature.

Results Advance directives should not be used in isolation to guide treatment decisions for patients with dementia. They rely on prospective decision-making and therefore may be outdated and inaccurate. They also fail to meet the criteria for informed consent as the individual cannot be fully informed about the decision and the impact of that decision on their current state.

Discussion Substituted judgement decision-making is one alternative to advance directives but this method also relies on prospective decision-making. Neither method takes into account the current wishes of the individual with dementia.

Conclusion The current wishes and interests of the individual with dementia should be taken into account in decision-making, alongside any previously expressed interests, such as those in an advance directive. Current interests an individual has, such as an interests in being alive, should trump interests expressed in an advance directive to refuse life sustaining treatment.