Drug addiction in the immigrant population of users undergoing the low-threshold methadone maintenance programme in Lisbon

Background:Drug addiction is an important public health issue of today societies. The literature shows that substance use disorders are associated with different cognitive and behavioural dysfunctions, however the role of psychosocial vulnerabilities in drug addiction is often neglected. This study aims at contributing to this topic by describing a vulnerable population of immigrants undergoing the low threshold methadone maintenance programme (LTMMP) in Lisbon, that reaches more than one thousand users in a daily basis. The comparisons between the population of immigrants with Portuguese users for sociodemographic characteristics and programme-related variables such as the type of patient reference, release and time in the programme will help understanding whether there are different profiles of users.

Method:The sample for this study was retrieved from the clinical files of Ares do Pinhal, an NGO that is responsible for the LTMMP in the city of Lisbon. The inclusion criteria in this study were: a) adult individuals b) undergoing the LTMMP. The total sample comprised 1191 individuals that were identified in a time window between January 2014 and December 2018.

Results:The data show that 21.5% of this sample are immigrants in the country, mostly from Europe (n = 128) with Ukraine, Romaine, Italy and France as the most representative countries, and Asia (n = 102) mostly from Nepal and India. The mean age of immigrant users (33yrs; SD = 8.1) was significantly lower than Portuguese users (M = 42yrs; SD = 8.2), where users from Asia were younger (M = 29yrs; SD=5.6). The distribution of gender was similar between native and foreign users of about 15% of female users in each group. The results showed that most the immigrant population reached the programme by its own initiative (88%) when compared to 68% of the Portuguese population. There was also a significant increase of the foreign population throughout the time period assessed, but not of the Portuguese population that remained stable from 2014 to 2018. Moreover, there was also a significant association with LTMMP releases, being the foreign users more likely to drop-out than the native users (78% vs. 48%) within the first year of the programme. The significantly higher proportion of ‘positive’ releases to more structured treatment structures in the Portuguese population vs. foreign users is also worth noting (54% vs. 17%).

Conclusions:These results are intriguing and suggest important vulnerabilities in foreign users. Foreign users are younger than the native Portuguese population, they have higher drop-out rates and most of them drop-out within the first year of the programme. Most of them reach the LTMMP by its own initiative, which suggest that these users are not included in formal networks for social support and health care. In sum, more importance should be paid to this population as this comprise almost one-fourth of the total population undergoing the LTMMP with a clear trend of increase in the last years.