“…As people who use opioids are surviving longer than 40 years, the cut-off point of 40 years has been used to define the 'older' population (Crome et al, 2009). There is no consensus in the literature on what 'old' is; it ranges from 37 to 55, 40+, 45+, 50+, 60+, 65+, 49 to 61, 50 to 59, and 50 to 74 Beynon et al, 2007;Boeri et al, 2011;Crome et al, 2011b;Doukas, 2011;European Monitoring Centre for Drugs and Drug Addiction, 2010;Han et al, 2009;Han et al, 2015;Institute of Medicine, 2012;Lofwall et al, 2008;Outlaw et al, 2012;Raffoul et al, 1981;Roe et al, 2010;Rosen et al, 2011;Schonfeld et al, 2000;Wu and Blazer, 2011).…”