Increasing trend and differential patterns of opioids prescribing by patient characteristics in primary care in Belgium: a registry-based study

Background

Since the 1990s, worldwide the number of opioid prescriptions has increased six-fold with the United States being the absolute leader in terms of number of prescriptions per capita. The increased rates of opioid consumption in Europe seems not to have resulted yet in an alarming increase in opioid related morbidity and mortality in the same way as in the US. However, careful monitoring is recommended in order to prevent a similar development. Therefore,we aimed to investigate trends of opioid prescribing in primary care and to study characteristics of patients being prescribed opioids in Flanders, Belgium.

Methods

The data analyzed in this study were derived from Intego, a Flemish General Practice registry. The study period ranged from, 2005 to December 2015 and concerned all patients 18 year and older.

Results

The number of patients being prescribed at least once an opioid increased by one third from 5% in 2005 to 6.7% in 2015 (p <0.001). Opioid prescribing steadily increased with age up to 88 years old from 1.9% to 11%. Women (7.6%) were significantly more often prescribed opioids than men (5.4%) (p <0.001). Opioid prescribing among cancer patients was 11.4 % in 2015 and remained stable throughout the study period. Among non-cancer patients of whom 62% had a previous orthopaedic diagnosis, opioid prescribing increased from 4.9 % in 2005 to 6.5% in 2015 ( p <0.001).

Among non-cancer patients opioid prescribing was significantly more likely among patients with a psychiatric diagnosis (p <0.001), patients with social problems (p <0.001), and patients on benzodiazepines (p <0.001).

The number of chronic opioid users among non-cancer patients increased from 1.2% in 2005 to 2.0% in 2015 (p <0.001). The likelihood of being prescribed opioids on a chronic basis was significantly higher in the presence of a psychiatric diagnosis (p <0.001), social problems (p <0.001), and concomitant benzodiazepine use (p <0.001).

Conclusions

An increasing rate of opioid prescribing in Flemish primary care was observed throughout the study period in non-cancer patients but not in cancer patients. Differential opioid dispensing patterns by patient characteristics may indicate potential inappropriate prescribing. However, further research should be performed to qualify and quantify the nature and extent of the problem if any.Effective strategies targeting clinicians andpatients are needed to curb rising opioid prescribing and to prevent opioid misuse or abuse.