Re: CAST replies

Drs Krausz and Marsh [BCMJ 2008;50(1):15] refer to the benefits of methadone maintenance therapy (MMT) while attemp­ting to make their argument for stimulant substitution. It took 20 to 30 years of clinical evaluation before MMT was accepted as therapy. 

Even if the proposed CAST therapy works, we believe studies of its effectiveness should be replicated in multicentre trials in differing patient environments before it is imposed upon a large population of patients. This is consistent with requirements for the adoption of any new treatment modalities.

We are not questioning the value of harm reduction; we support it in our practices with our patients. What we take issue with is a major trial (3000 patients by 2010) using a highly vulnerable population based on studies that are short and at best question­able in terms of their outcomes. Given this, it is unethical for physicians and researchers to experiment with this population, even if we expect society to benefit. 

The lack of access to nonpharma­cological and psychosocial treatments—such as detox-on-demand, day programs, in-patient programs, safe housing, and access to health care—together with the high incidence of concurrent mental disorders has contributed to Vancouver’s Downtown Eastside being what it is today. It is heartening to know housing access initiatives—a nonpharmacological intervention CAST considers imperative—are being introduced independent of the study and will be available beyond the time of the trial and to those not enrolled. 

It is not our objective to hold back the advancement of beneficial therapies. However, it is wrong for research­ers to presume positive outcomes from any study prior to its completion, let alone advocate for its benefit (despite the availability of research funding streams). In doing so, there is a high risk of bias in data collection, analysis, and interpretation. This is basic science and cannot be overstressed. 

The example of hypertension offered by Drs. Krausz and Marsh is overly simplistic but offers a valu­able warning; the rapid, widespread adoption of short-acting nifedipine treatment led to increased overall mortality and should be viewed as an object-lesson to all researchers.[1] We take issue with the comparison of stimulant substitution to other secondary therapies used in the treatment of hypertension. The recent observation that tight glycemic control in diabetics increases mortality should cause everyone to pause and reflect that something intuitively obvious may not lead to the best outcomes.

We did not “misunderstand” the primary goal of CAST. We quoted directly from the web site. Since publication of the original BCMJ article, the CAST web site has been modified. When we wrote the article, the web site explicitly stated that “Substitution therapy is a means of reducing the user’s impact on public order and public health until durable solutions are reached.” 

As frontline health care workers, we feel the need to raise concerns and give a voice to the potential negative impacts of this initiative on the addicted individuals we treat on a daily basis. The argument that “people are dying” and “we must do something” cannot be a substitute for ethical and clinical neutrality. 

It remains our position that CAST is not good for this patient population or for the city of Vancouver, and we believe it is unconscionable to use CAST as part of a city-wide political agenda.

—Ray Baker, MD
—Katie Bertram, MD
—Doug Coleman, MD
—Patrick Fay, MBBCh
—Martin Gerretsen, MD
—Carolyn Hall, MD
—Donald Hedges, MD
—Rob Hewko, MD
—Colin Horricks, MD
—Shao-Hua Lu, MD
—Karima Jiwa, MD
—Ramanjot Mangat, MD
—Jennifer Melamed, MBBCh
—Larina Reyes-Smith, MD
—Paul Sobey, MD
Vancouver

References

1. Furberg CD, Psaty BM, Meyer JV. Dose-related increase in mortality in patients with coronary heart disease. Circulation. 1995;92:1326-1331.