Experts at the Congress of the European Pain Federation EFIC in Florence, Pain in Europe VIII, viewed the increasing prescription of opioids in the treatment of pain with mixed feelings. More than 4,000 participants from around the world have gathered at the event to exchange ideas about innovations in pain management. Improvements in the provision of opioid treatment for sufferers were welcomed, but figures presented revealed large and alarming discrepancies in access to these important drugs. Current studies also make clear that in some cases opioids are prescribed with too free a hand, ignoring potential side effects and risks of abuse.

Increasing consumption, but varying access

"Opioid drugs are most effective as analgesics; they are now prescribed 7.5 times more often than they were in 1990. Annual consumption worldwide has climbed from 7.67 milligrams to 58.11 milligrams (mg) per capita. Drugs based on these substances were long considered taboo due to their alleged addictive nature, but in recent years their usefulness in treating patients with severe chronic pain has clearly been recognised in medicine and in health policy," said EFIC President Prof Hans Georg Kress (Vienna, Austria).

At first sight, the global statistics disguise the true state of affairs - that by no means everybody in the world benefits from the effectiveness of these drugs. Even within the WHO European Region there are major treatment gaps. Although between 1990 and 2010 there was an almost 15-fold increase in the use of opioids, from 9.2mg to 135.11mg per capita, this statistical average masks some striking variations from country to country. While in the three European countries with the highest consumption - Denmark, Austria and Germany - the average per capita prescriptions were 469.79mg, 413.40mg and 375.98mg respectively in 2010, in other countries not even the most common drugs used against cancer pain were available. In countries such as Kazakhstan (0.05mg per capita) and Tajikistan (0.04mg per capita) the frequency of use of opioids is vanishingly low. Inside the EU, Poland (33.08mg per capita), Lithuania (38.43mg per capita) and Latvia (24.90mg per capita) have the lowest rates of opioid prescription. "There are obviously unmet medical needs, and healthcare policy makers can no longer be allowed to ignore them while millions of people are condemned to lives of agonising pain. This is medically and ethically unacceptable," Prof Kress insisted.

The right medication for the right patients

At the same time, Prof Kress stressed that the amounts prescribed should not be the sole consideration: "We must look at the increasing use of opioids from a number of different angles. Opioids are not without side effects, and for this reason they should only be prescribed in cases where patients do not have adverse reactions, where there are long-term benefits, and where other methods of treatment have failed." In addition to well-known side effects such as constipation, nausea and dry mouth, opioids can trigger a range of other reactions, the significance of which is often underestimated. They affect the hormonal system and metabolic processes. This was demonstrated in a Spanish study presented at the EFIC Congress (EFIC Abstract Ferri et al). More than 40% of the patients investigated complained of side effects such as nervousness and sexual dysfunction, and more than 30% suffered from insomnia or depression. Another international study presented at the Congress suggested that many patients are given opioids where there are no clinical benefits (EFIC Abstract Stannard et al).

Prevention of abuse

More generous use of opioids in recent years has brought with it another issue: drug abuse. "This problem is most serious in North America and Australia, because the prescription of opioids is less strictly regulated than in Europe, where access is closely controlled by the use of special prescription forms or drug registers," explained Prof Kress. It may make sense to establish whether patients are at risk of drug abuse before the start of therapy. "A recent Italian study (EFIC Abstract Ferrari et al) shows that specially designed questionnaires are a reliable diagnostic tool for this purpose, and recommends evaluation of patients' mental health before prescribing opioids," Prof Kress added.

A Norwegian study presented at the EFIC Congress (EFIC Abstract Fredheim et al) also showed that it is not always the appropriate patients that receive long-term opioid therapy. Data from more than 17,000 persons were analysed. "Over five years, 34% of the patients doubled their opioid dosage. It is cause for concern that a steep increase in dosage is a common phenomenon in long-term therapy. Moreover, high dosages are generally accompanied by heavy consumption of benzodiazepines, which are addictive tranquillisers," said Prof Kress. This is all the more worrying because a Danish study has also revealed a strong link between chronic pain, opioid and benzodiazepine use, and certain other risk factors (EFIC Abstract Hojsted et al).

Guidelines for general practitioners

"As the European specialist organisation, we are making the case for a sensible middle way between underprescription, overprescription, and the problems of drug abuse. There is no point in throwing the baby out with the bath water and allowing misuse in some parts of the world to result in worldwide restrictions. This would place insuperable barriers in the path of patients urgently in need of opioids to manage their pain," the EFIC President pointed out. A reasonable approach would be to screen patients to see whether their conditions respond to opioids without serious side effects, and to establish whether they are exposed to the risks of abuse or addiction.

In relation to these ideas Prof Kress drew attention to a British study presented at the EFIC Congress (EFIC Abstract Singh et al), which revealed that general practitioners in particular want clear guidelines. The study also showed that better patient information brochures are needed, and that opioid treatment agreements could provide a sensible basis for dealing with chronic pain patients.