**3. Demographics/epidemiology**

Overall, the populations of Western countries are ageing, and it has been suggested new technologies in forensic science, changes in prosecution and sentencing laws, alongside reduced options for early release, have contributed to the growth of the older prisoner population [6, 7]. Australian population statistics show the numbers of Australians aged 50 years and over increased by 36.8% in the period 2000–2010 [25, 26]. However, there was an increase of 70.4% in prisoners aged 50–54 years, 79.7% in prisoners aged 55–59 years, 81.8% in prisoners aged 60–64 years and 141.7% increase for the over 65 year old group from the year 2000 to 2012 [26]. This increase in the number of older prisoners has been identified across the world [27]. Accompanying this there is an expected rise in the rate of chronic disease including cognitive impairment and dementia in correlation to the rise in the general population [25, 28].

The World Alzheimer Report 2016 [29] identified in 2016 that there were approximately 46.8 million people across the world with dementia and this is expected to increase by the year 2050 to 131.5 million people. Alzheimer's Disease International [29] recognised that different income level countries have different levels of identification of dementia. For example in low and middle income countries there are only 10% of people with diagnosed dementia, whereas in high income countries this rises to about 50% being diagnosed [29].

Approximately 13% of the general US population aged over 65 years have dementia whereas in the prisoner population it can be as high as 44% [30]. Baldwin and Leete [31] reported that a UK survey of prison inmates provided evidence that 15% of those surveyed exhibited signs of cognitive impairment. This was then used as an indication that there could be many unrecognised instances of dementia in prisons [31]. Correctional settings have not been prepared to address the needs of older, infirm or disabled prisoners which create a strain on staff [31]. For instance, it is now recognised that correctional services staff are not trained to identify a person with a cognitive impairment or care for someone who is disabled, rather, they are employed to manage prisoners' behaviour [31].

Despite the fact that an increased awareness of the ageing population and dementia has been a major focus of literature on older people, there is minimal documentation about how this is impacting the correctional setting [5]. Maschi et al. [30] (p. 442) state that there is 'no national study to estimate prevalence of dementia among the U.S. prison population'. Williams et al. [32] also identified that there has been minimal research into the prevalence of dementia in the correctional setting, and based on other data, they expect cognitive impairment to be high and unrecognised in the older prisoner population. There is limited research into the early identification of dementia in the prisoner population, with correctional healthcare services having a strong focus on acute healthcare issues rather than long term preventive measures [33]. This correctional setting has given rise to increasingly complex healthcare needs in the prisoner population which is directly linked to the increase in the ageing population in this setting [34].
