Background Advance care planning (ACP) involves patient’s ability to understand medical scenario and treatment, reflect upon his/her values and verbalise preferences. Decision Making Capacity (DMC) is necessary for making medical treatment choices. Clinical literature and legal frameworks have suggested four consent standards to assess medical DMC- communicating a treatment choice, understanding the treatment situation and choices, weighing up treatment choice (reasoning) and appreciating the personal consequence of treatment choice. This potentially poses a problem for ACP with people suffering from cognitive impairment/dementia as his/her medical DMC may be questionable.

Aim Provide synthesis of current studies examining the consent capacity of patient with cognitive impairment/dementia.

Methods We reviewed extant studies examining consent capacity of patients diagnosed with cognitive impairment and dementia as of Dec 2014.

Results Progressive decline in understanding capacity is evident in patients across the dementia continuum. Studies have shown that deficit in understanding is associated with progression of the disease over time. Decline in reasoning and appreciation functions are also evident in patients with mild-moderate dementia, with some studies reported similar progressive decline of over time. However, patients at different stages of dementia retain varying capacity to communicate choices, with the exception of patient suffering from Parkinson’s Disease (PD).

Discussion Patient’s variable ability to consent as determined by assessment of DMC necessitates timely consent-seeking. Strategies have been suggested to capitalise episodic consent-seeking in order to maintain validity of the decision made.

Conclusion There are still relatively sparse ACP related decision making studies and perhaps other factors that are involved in decision making process can be further examined.