5 December 2008

APSAD Annual Scientific Conference 2008 [part II]

APSAD Annual Scientific Conference 2008 [part II]
November 23 - 26, 2008

The plenary sessions on Tuesday were excellent, starting out with an American statistician, Rosalie Liccardo Pacula talking about the new generation RAND drug use modelling. This appears to be an enormously detailed, almost 4-dimensional system of looking longitudinally at multiple individual markers as well as societal/drug changes. Already they are able to predict drug trends with far fewer people than household surveys but there is still more work to be done to hone this new tool. Like all statistical models, it is only as good as the information fed into it. [http://www.apsad2008.com/abstract/300.asp]

Next we heard Prof Ross Homel giving a talk about complex family interventions, often involving three generations, with the emphasis on child safety, development and education. He gave numerous examples of what they are doing in a non-Government organisation associated with Mission Australia. There were vastly diverse interventions from group therapies, vocational referrals to literacy programs. Their main aim was to embed such programs into schools where there was a high proportion of disadvantaged children.

It was most appropriate that Prof Ann Roche gave the Rankin Oration this year. She did a broad overview of our field and her involvement in it looking back and then giving some views about the future using many clever and apposite quotes from Woody Allen, Elenor Roosevelt, the Dalai Lama and others. One memorable quote from the conference was a post-modern concept for the single woman to ask of any man she dates: �Is this really the man I want to look after my children on weekends?�

Greg Dore then revealed just what we all needed to know about hepatitis C. He dealt with the progress of the epidemic since it was first formally recognised in our communities around 1990. With no initial symptomatology in most patients, it is hard to determine the true incidence. However, by looking at the prevalence in young age groups one can determine changes from time to time. This would seem to indicate that although there are still many reported new cases each year, fewer of these appear to be true new infections as the prevalence in younger people is dropping more rapidly than in the overall population. [http://www.apsad2008.com/abstract/294.asp]

The range of treatments was detailed, pointing out the major improvements in recent years. We can now expect up to 80% �cure� rates (absent viral PCR at 6 months) in genotypes 2 and 3 with around 50% for genotypes 1 and 4. With several innovations such as closer viral load monitoring, liver "fibro-scans" and treatments for anti-viral side-effects, better results can be expected in the next few years. It is only by combining all of our resources, including GPs, addiction clinics, pharmacies and liver specialists that we will be able to address this epidemic which has a high proportion of patients on opioid therapies.

A talk was then given by Marina Davoli from Rome about the Cochrane Collaboration and internet library. Australia has had a special contribution to several areas and we have the only free access for internet users. Australian and New Zealand have also contributed much more serious research than other comparable western countries by population. This underlines all the evidence based interventions we use today.

I missed the session chaired by Dr Deborah Zador on opioid overdose but happily the conference abstracts are all available on the internet (see below). Dr Zador wrote some of the most important seminal studies on the subject in the 1990s. Two papers were given about naloxone, both its distribution amongst the drug using population and intriguingly by the intranasal route by paramedics in the overdose situation. The �Good Samaritan� provisions and international developments were detailed by Paul Dietze and Simon Lenton. [http://www.apsad2008.com/session/353.asp]

Bethany Butler reported some more results in an on-going study of several thousand NSW cases starting for the first time on methadone (~2500) or buprenorphine (~3500). There was no significant difference in the overall mortality in the groups (~65 subjects in each) but an excess mortality (~5-fold) in the methadone group in the first 2 weeks of treatment (7 versus 2). As well as direct toxicity, this might also be explained by methadone patients being in a higher risk group to start with. Even so, only a randomised trial can scientifically compare the two treatments and this is probably no longer ethical as most patients know which drug they want (see Pinto). It is certainly gratifying that when used in the normal course of practice that patients on each of these drugs have a marked drop in mortality. This study found those who remained in treatment were about three times less likely to die.

Next Louisa Degenhardt gave a paper on her group�s investigations of all deaths in NSW opioid maintenance cases since 1985, showing some differences over time. Overall 0.9% of subjects died each year of follow-up: 0.6% for those in treatment compared with 1.2% for those who had left. There was with a much higher chance of dying in the first two weeks of treatment when rate was 4.2%. This latter has dropped significantly since the early 1990s and does not apply at all to buprenorphine cases. The authors state that the treatments have the same mortality rates since those on buprenorphine have a lower retention rate, consistent with the comparative literature.

Finally, the session was given information about significant reductions in local ambulance attendances during the opening hours of the Sydney injecting centre (MSIC) as well as comparisons with the 2 years prior to its opening.

On the Wednesday morning we heard a plenary talk by Nicholas Lintzeris on the directions of treatment in the 21st century. He alluded to the shortage of doctors working in the field, the use of new medications requiring less supervision and models of treatment from elsewhere such as France. His subtext seemed to be individualising treatments rather than having rules and one-size-fits-all. He quoted the average age of methadone prescribers approaching the average daily dose! [Which is now about 75mg!] The speaker also did a study with Adam Winstock regarding attitudes towards withdrawal from treatment.

Next, those of us nursing a headache from the previous night�s dinner at L�Aqua Restaurant were given a fascinating talk by Sharon Walsh who is working in Kentucky on the effects of non-medical use of pharmaceuticals. She reminded us that in some areas there is now as much or more such abuse as for heroin. [This was also reported recently from inner Sydney in an ABC radio story which was nominated for a Walkley Award.] The emergence of prescription drug abuse may mean that we need to alter our approach and will increase the need for treatment services. Despite street and prescription drug use having essentially the same dependency diagnosis, these occur in quite different demographics (see Dr Strain�s talk from Sunday). The new RACP Policy on Prescription Opioids and Chronic Non-malignant Pain was introduced in another session, mapping out a plan for problematic use of prescription opioids in Australia and New Zealand [http://www.apsad2008.com/session/374.asp].

Dr Walsh reported on her results in human laboratory studies on oxycodone (Oxycontin; Prolodone), hydromorphone (Dilaudid) and hydrocodone. The latter is not available in Australia but is a constituent of Vicodin, a commonly abused drug in America. While hydromorphone is thought to be about 7 times stronger than morphine for its analgesic effects, in experiments on recreational users the differences between these three drugs were only marginal. [http://www.apsad2008.com/session/380.asp]

Despite running short of time, the next speaker Mark Tyndall spent some minute or two giving a hilarious description of the harm reduction aspects of pedestrians running red �WALK� signs. Next the hapless visiting Canadian described his shock at being taken to a surf beach where crashing waves buffeting swimmers who risked life and limb against the elements which were anything but �pacific� of late. His implication, I think, was that life savers are the equivalent of harm reduction services for drug users.

Returning to his subject, a square kilometre of western urban Canada, there were an estimated 6000 drug users, mostly injectors, of whom 25% had already contracted HIV and 90% hepatitis C. Services were and are grossly inadequate despite statistics which show disastrous rates of just aboot everything one would not want in one�s neighbourhood (crime, public injecting, overdose, deaths, hospital admissions, HIV cases, infections, etc). The Vancouver injecting centre is slightly larger in scale and opening hours, but shares all the essential characteristics of the Sydney injecting centre at Kings Cross (on which some say it was modelled). It has registered over 10,000 Canadian drug users (not all injectors as in Sydney). There are moves to close down this centre despite a wealth of public health research showing benefits to drug users and the community generally at modest cost (or even a net saving to the health system). Its closure would be a most pointed and poignant natural experiments in public health, comparable perhaps with the Broad Street pump exposure in London in the 1800s.

Next I attended a break-out session in which Carla Treloar spoke about the impressions people had about hepatitis C (http://www.apsad2008.com/session/388.asp). The myths were myriad. Defeatist misconceptions abounded. Some of her quotes were classics. Clearly our first job with hepatitis C is to inform people about the truth. Yes, the disease is still difficult and poorly understood. But we now have simple ways of determining the stage of the disease (�fibroscans�, risk criteria, etc) and we have reasonable and tolerable treatments with success rates up to 80%.

Nick Lintzeris reported some findings of an excellent intervention started some years ago in western Sydney in which OTP patients were offered a rapid vaccination program for hepatitis B. The results and a literature review showed that people at risk should probably be given a booster just about any time they are prepared to take one when it is available, even in quite short succession or as a booster down the line. Strict and appointment based regimens are perhaps not best suited to our patient group and so haphazard inoculations are probably more effective than no inoculations at all.

Some 9 cases of bacterial endocarditis in Newcastle area were reported next by Andrew Taylor. These formed a small minority of the total number of such cases in the region. Candida and staphylococcus aureus were common pathogens. The costs of such treatment to the health care system were high and the savings in prevention substantial.

The final segment of the conference for me at least was our own pet topic, hepatitis C outcomes. Carolyn Day, Paul Haber and colleagues reported on the barriers to addressing this public health priority (http://www.apsad2008.com/abstract/263.asp). From the low rates of assessment and treatment, even some prominent and well run clinics seem not to have effective strategies for testing and referring their patients. Some have no idea what proportion of their patients have been tested. Where resources allow, this can be pro-active, �on-site� and direct to hepatology services. Alternatively, referral to the individual patient�s GPs may be the best way to handle such matters in some situations. It is no longer acceptable to do nothing as advocated by some, claiming that �the treatment is worse than the disease�(!!). Some clinic practices seem so calcified that they have not even managed the change from methadone syrup (containing alcohol, caramel, sorbitol, gum, etc) to the safer �pink� methadone, despite majority patient support where the transfer was done some years ago (eg. NSW prisons; Rankin Court, Langton Centre, Clinic 36, Regent House, etc). At a recent health department forum at North Sydney some senior salaried clinicians described every barrier to improved treatment except themselves!

Next I moved to the session on intervention outcomes where Richard Hallinan reported our own 6 year experience prioritising hepatitis C assessments in OTP cases in Redfern (http://www.apsad2008.com/abstract/270.asp). We used some simple criteria devised by Greg Dore to indicate the likelihood of disease progression with liver fibrosis or cirrhosis. Some findings were given from 315 consecutive assessments with follow-up results for 30 cases having anti-viral treatment. Pegylated interferon alpha plus ribavirin were monitored in a shared care model with specialist hepatology services, with encouraging results thus far showing an overall 74% sustained viral response.


Comments by Andrew Byrne ..

Surgery web page: http://www.redfernclinic.com/#news

Opera blog: http://www.redfernclinic.com/opera/critique/blog/

New York in 2008: http://ajbtravels.blogspot.com/

New York diaries 1922: http://bpresent.com/harry/code/10b_bowery.php

Travel log: http://www.redfernclinic.com/c/2007/10/lord-howe-island-naturalists.php4

Vincent Dole in Nepal Diary: http://vincentdolehimalaya.blogspot.com/

Old photos of Sand Souci: http://sanssouciphotos.blogspot.com/


Reference:
Pinto H, Rumball D, Maskrey V, Holland R. A pilot study for a randomized controlled and patient preference trial of buprenorphine versus methadone maintenance treatment in the management of opiate dependent patients. Journal of Substance Use 2008 13;2:73-82

�Current policy puts too much emphasis on protecting society from methadone, and not enough on protecting society from the epidemic of addiction, violence and infections that methadone can help reduce.�

Institute of Medicine 1995