Remarks y The term “non-pharmacological intervention” is used to describe a wide range of cognitive, psychological/psychosocial and environmental interventions that are not necessarily mutually exclusive categories (i.e. interventions may fall into or incorporate aspects of multiple categories). Brief descriptions for all recommended interventions (in alphabetical order) are provided below.

• “Cognitive behavioural therapy (CBT)” is an umbrella term covering a wide range of psychological approaches that aim to improve affective function. CBT focuses on the process of thought rather than content to help people accept their thoughts.
• “Cognitive stimulation therapy” is a nonpharmacological intervention often involving group activities and social interaction used to treat cognitive decline in people with dementia. It encompasses a variety of approaches including reality orientation, validation, and/ or reminiscence. Cognitive stimulation aims to improve global cognition and maintain function by stimulating multiple cognitive functions simultaneously, typically with group activities emphasizing social interaction. This approach is different from cognitive training, which targets isolated cognitive functions (e.g. memory) with individual, repetitive practice of standardized cognitive tasks.
• “Cognitive training” is an umbrella term referring to a group of non-pharmacological interventions in which a range of techniques are applied to engage thinking and cognition with various degrees of breadth and specificity. The goals include improving or maintaining cognitive processes or addressing the impact of impairment in cognitive processes on associated functional ability in daily life.
• “Physical activity” here refers to aerobic (cardiovascular conditioning) and anaerobic (strength training) exercises. In the WHO guidelines on risk reduction of cognitive decline and dementia, physical activity is also recommended for adults with normal cognition to reduce their risk of cognitive decline and may be recommended for adults with mild cognitive impairment to reduce the risk of further cognitive decline (124). The WHO guidelines on physical activity and sedentary behaviour recommend that all adults ages 18–64 (not specific to those with dementia) “should do at least 150–300 minutes of moderate-intensity aerobic physical activity; or at least 75–150 minutes of vigorous-intensity aerobic physical activity; or an equivalent combination of moderate- and vigorous-intensity activity throughout the week, for substantial health benefits” (68). y A range of other non-pharmacological interventions and activities may be effective in managing individual symptoms of people with dementia but due to the low level of evidence and/or limited effectiveness on individual outcomes no specific recommendation has been made for their use. These interventions include the following (in alphabetical order).
• Animal-assisted therapy showed a medium beneficial effect on reducing depressive symptoms with a low level of certainty.
• Aromatherapy (lavender or melissa) may reduce agitation to a variable extent, especially for individuals with severe dementia, when used for shorter periods (i.e. 4 weeks or less) and applied through methods other than massage. The overall level of certainty was low, with the exception of use of melissa, which had moderate level of certainty.
• Assistive technology may reduce the risk of falls in people with dementia with low level of certainty.
• Dance-based interventions and music therapy may reduce depressive symptoms slightly with a very low to moderate level of certainty. Music therapy may also improve cognitive function slightly, with a very low level of certainty.
• Horticultural therapy may be beneficial for treating/managing agitation in people with dementia with a moderate level of certainty.
• Mindfulness-based interventions showed large positive effects on cognition and everyday functions with a very low level of certainty based on a single trial.
• Multimodal interventions including art therapy showed very small effects on reducing depressive symptoms with a very low certainty.
• Personally-tailored activities may slightly reduce overall behaviours and psychological symptoms associated with dementia with a low level of certainty.
• Reminiscence therapy showed medium-tolarge positive effects on depressive symptoms irrespective of dementia severity, but especially in people under the age of 80 and when delivered in group settings with very low to low levels of certainty. y In line with current human rights standards and WHO’s Towards a dementia-inclusive society – a toolkit for dementia-friendly initiatives (125) – it is important to promote inclusion and participation of people living with dementia in all activities, hobbies, pastimes, community events/gatherings based on the person’s preferences to foster social functioning and well-being.

Implementation considerations y Tailor any intervention to the individual needs and preferences of the person living with dementia and their family/carers. Review regularly and adjust for dementia severity and decline over time. y Tailor any intervention/support offered to individuals to their needs and abilities at the time, present choices and review/reassess at regular intervals to reduce the likelihood of interventions causing unintentional harm/adverse effects (e.g. through frustration, overload). Also consider the needs and preferences of carers. y Costs associated with delivering individual non-pharmacological interventions will vary substantially by the type of intervention, but overall seem feasible in low-resource settings.