Pain in methadone maintenance therapy

Introduction
Patients receiving methadone maintenance treatment often suffer from pain due to the occurrence of opioid-induced hyperalgesia. Pain is indicated as one of the key factors causing poor treatment outcome and is correlated with worse quality of life. The aim of the present study was to analyse the frequency of pain in Polish patients treated in methadone maintenance programmes and to evaluate the relationship between pain and physical and mental health, as well as patients’ social functioning.

Material and methods
The study group included 237 methadone maintenance treatment patients. They were asked to complete the Brief Pain Inventory and other standardised scales and questionnaires to assess the relationship between pain and some clinical variables.

Results
In the present study, 54% of patients reported experiencing pain, however 66.9% of them did not take any medications (analgesics included). Persons suffering from pain in comparison to those without pain more often attempted suicide, were alcohol dependent, experienced childhood maltreatment and assessed their quality of life as worse.

Discussion
Our results are in line with those of other authors, especially regarding the relationship between child abuse, poor quality of life, inadequate analgesia and developing pain syndrome. On the other hand, the conducted study did not reveal any relationship between pain and administered methadone dose.

Conclusions
Pain is one of the most serious problems among methadone maintenance treatment patients and should not be neglected as it leads to decrease in the quality of life and increases the risk of suicide. This implies an increased necessity for routine assessment and pain management in these patients.