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On: 9 February 2009

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Journal of Substance Use

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Attitudes and knowledge of substance misusers regarding buprenorphine and

methadone maintenance therapy

H. Pinto a; D. Rumball a; R. Holland b

a Trust Alcohol and Drug Service, Norfolk and Waveney Mental Health Partnership Trust The Bure Centre, Norwich NR2 2PA b School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, NR4 7TJ

Online Publication Date: 01 June 2008

To cite this Article Pinto, H., Rumball, D. and Holland, R.(2008)'Attitudes and knowledge of substance misusers regarding buprenorphine and methadone maintenance therapy',Journal of Substance Use,13:3,143 — 153

To link to this Article: DOI: 10.1080/14659890701639808 URL: http://dx.doi.org/10.1080/14659890701639808

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ORIGINAL ARTICLE

Attitudes and knowledge of substance misusers regarding

buprenorphine and methadone maintenance therapy

H. PINTO

1

, D. RUMBALL

1

, & R. HOLLAND

2

1

Trust Alcohol and Drug Service, Norfolk and Waveney Mental Health Partnership Trust The Bure Centre, 7 Unthank Road, Norwich NR2 2PA, and2School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, NR4 7TJ

Abstract

Aims: To assess substance users’ beliefs and the sources of these beliefs regarding methadone and buprenorphine and to examine how they choose between them.

Design: Forty-two opiate-dependent patients seeking treatment chose between open label buprenorphine or methadone maintenance treatment. Prior to treatment patients completed a semi-structured interview or a self-completed questionnaire.

Findings: Beliefs were based primarily on their own or other users’ experiences. All patients chose their treatment. There was little difference between those choosing MMT and BMT in terms of their beliefs about the drugs, although the BMT group viewed methadone more negatively and buprenorphine more positively than the MMT group. Those choosing MMT appeared to do so on the basis of familiarity whereas those choosing BMT appeared to be attracted by their beliefs that it would block heroin more effectively, reduce craving, give less intoxication and be easier to stop taking. Conclusions: Opiate users rapidly become well informed about a new treatment when it becomes available. They rely more on their own and other users’ experience than the information given by agencies. Choices between treatments are based more on individual perceived requirements than different beliefs.

Keywords: Qualitative, buprenorphine, methadone, maintenance, attitudes.

Introduction

Methadone maintenance therapy has been the mainstay of treatment for opiate dependence in the UK for several decades. Methadone is a pure agonist at the mu opiate receptor, is well absorbed orally and has a long half-life. Evidence suggests that methadone maintenance therapy improves physical and mental health and social functioning and reduces criminal behaviour (Marsch, 1998). However, as a full agonist, methadone causes respiratory depression in overdose and there is concern about the number of methadone related deaths [Advisory Council on the Misuse of Drugs (ACMD), 2000]. Some argue that methadone maintenance therapy prolongs the period of dependence as it requires

Correspondence: Dr H. Pinto, The Bure Centre, 7 Unthank Road, Norwich, Norfolk NR2 2PA, UK. Tel: 01603 671900. Fax: 01603 671920. E-mail: [email protected]

ISSN 1465-9891 print/ISSN 1475-9942 online#2008 Informa UK Ltd. DOI: 10.1080/14659890701639808

continued daily dosing and eventual detoxification is considered to be protracted which may deter some from seeking abstinence. Furthermore, epidemiological studies suggest that only about 20% of those addicted to opiates are recruited into treatment in the UK (Millar, Gemmell, Hay, & Donmall, 2004). The reasons for this are many and varied but include the commonly held belief that services are primarily methadone clinics and this drug may have strong negative connotations for some drug users (Stancliff, Myers, Steiner, & Drucker, 2002).

In 1999 buprenorphine was licensed for opiate maintenance treatment in the UK. Prior to this, although there had been some unlicensed use of dihydrocodeine, there had not been a realistic alternative to methadone. Buprenorphine is a partial agonist at the mu receptor and, hence, is safer in overdose, ceiling effects on respiratory depression being reached at about 16 mg (Walsh, Preston, Stitzer, Cone, & Bigelow, 1994). It is easier to withdraw from (so much so that it is used as a detoxification agent) and has the potential to be given at up to three day intervals, possibly encouraging shorter periods of maintenance. Buprenorphine provides a more effective opiate receptor block, reducing the effect of additional opiates, which should in theory reduce illicit opiate use ‘on top’ of a prescription. Existing evidence regarding effectiveness in terms of retention in treatment and suppression of illicit opiate use slightly favours methadone (Mattick, Kimber, Breen, & Davoli, 2003), which is also significantly less expensive. Nonetheless, clinicians have increasingly prescribed buprenorphine for maintenance therapy over the past few years. The reasons for this are unknown, but may include the advantages listed above. Some clinicians question the applicability of the results of the existing RCTs to current practice (particularly relating to induction and dosing schedules for buprenorphine). Some feel that the ability to offer a choice is itself important and local experience suggests that drug workers find the discussion around choice an aid to initial engagement.

Little is known about the views of substance users. Recruitment in to drug treatment and the success or failure of treatment is affected by the beliefs people have about that treatment. A small number of trials have assessed the attitudes of opiate users to methadone treatment (Brown, Benn, & Jansen, 1975; Fischer, Chin., Kuo, & Vlahov, 2002; Hunt, Lipton., Goldsmith, Strug, & Spunt, 1985; Rosenblum, Magura, & Joseph, 1991; Stancliff, Myers, Steiner & Drucker, 2002; Zule & Desmond, 1998), but none have addressed views on buprenorphine. Drug cultures can change rapidly, therefore, some of the older trials may be of limited relevance. None of the trials have been conducted in the UK. Hence, it is important that in offering a choice of treatment that we develop an understanding of:

N

substance users’ knowledge about and attitudes to these drugs;

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_{the sources from which these are gained;}

N

which aspects are most salient to them in their decision process.

This study is a preliminary investigation of substance users’ attitudes to and knowledge about these two drugs, and sets out to begin to address the question as to how they choose between them.

Method

The methods of the trial of which this was a sub-study are described in a previous paper (Pinto, Rumball, Maskrey, & Holland, 2007). Briefly, participants attending for a new opiate maintenance script in August to November 2003 at the Bure Centre in Norwich were offered the opportunity to take part in a pilot for a randomized trial/patient preference

study of methadone and buprenorphine treatment. Participants needed to be over 18 years of age, not pregnant or breast feeding, and sufficiently physically and mentally well to be treated with either drug and give informed consent.

Methadone had been prescribed locally for many years and buprenorphine was relatively new, having been prescribed for 2 years. Individuals who were not happy to be randomized were given free choice as to their maintenance drug if considered physically appropriate for both by the treating clinicians.

Formation of questionnaire

As there were no relevant pre-existing instruments for assessing patients’ beliefs about buprenorphine and methadone, or how they chose between them, the first 13 participants were asked two open questions about both drugs: ‘What do you know about methadone/ buprenorphine’ and ‘What do you think about methadone/buprenorphine’. On the basis of their responses a questionnaire for self-completion was compiled, based around five-point Likert Scales, covering three key areas:

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starting treatment;

N

being on treatment;

N

_{coming off treatment.}

Questions were included concerning previous experience with the drugs, their taste and their source of information about the two drugs. Finally participants were asked to give a reason for their choice of drug (some gave more than one reason) and asked for ‘any other comments’ with the probe ‘For instance, do you know about any side effects’. A total of 29 participants (14 methadone, 15 buprenorphine) completed the questionnaire (See figure 1). Ethical approval for this study was obtained from Norwich District Research Ethics Committee. Informed consent was obtained from all participants.

Analysis

Data from the Likert scales did not appear to be normally distributed; therefore, non-parametric tests were used. The data from the questionnaire were compared in two ways:

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individual participants’ views of the two drugs were compared using the Wilcoxon

signed-rank test;

N

_{the views of all those who chose buprenorphine were compared with the views of those} choosing methadone using the Mann–Whitney test.

As a total of 41 different statistical comparisons were made we set the level at which results were considered statistically significant asp,0.001. Where a difference was such that 0.001,p,0.05 this was interpreted to represent only a potential statistically significant difference.

Results

A total of 87 patients were considered eligible to participate of which 56 (64%) agreed. 42 of these actually attended for induction. No patient agreed to be randomized. In total, 22 participants chose methadone and 20 chose buprenorphine.

Figure 1. Self-complete questionnaire.

Baseline group characteristics

Baseline characteristics of the two groups were broadly similar. The only difference reaching statistical significance was that participants choosing buprenorphine were significantly less likely to have previously received methadone maintenance therapy (77 vs. 40%, p50.015). Otherwise the groups appeared to be reasonably well matched. Full details comparing baseline characteristics are available in the previous paper (Pinto et al., 2007).

Sources of information about buprenorphine and methadone

Participants gained their views from a variety of sources, but tended to rely primarily on their own or other users’ experiences (see Table I). Combining prescribed and illicit use all but one had personal experience of methadone (96%), whereas only 62% had tried buprenorphine.

Beliefs about methadone and buprenorphine

The results suggest that the individuals who completed the questionnaire regarded buprenorphine and methadone to be similar in terms of the likelihood of experiencing withdrawals when starting to use them, in their ability to suppress withdrawal symptoms during regular use and in the stigma associated with their use (see Table II). However, they appeared to perceive them as quite distinct in other ways. They believed (p,0.001) that buprenorphine was more likely to block the effect of illicit heroin use, would leave the user more clear-headed, cause less sedation, have less of a numbing effect on emotional reactivity and would eventually be easier to stop taking. They also appeared to believe (p,0.05) that, while buprenorphine tasted worse it was safer in overdose, reduced craving more, and that treatment with this drug was less like an alternative addiction.

The beliefs expressed about each drug by those choosing methadone were generally very similar to the beliefs of those choosing buprenorphine. However, whilst the direction of difference was the same, those choosing methadone perceived less of a difference between the two drugs in terms of clear-headedness, sedation, difficulty of detoxification and the degree to which they represented an alternative addiction than the group choosing buprenorphine (data available from the authors).

Comments

The reasons given by participants from the whole sample (i.e. the initial thirteen participants interviewed plus those completing the questionnaire) for their choice of drug Table I. Sources of information about buprenorphine or methadone

Source of information (n528)*

Self (own experience) 17 (61%)

Other user 15 (54%)

Drug worker 13 (46%)

Leaflet 9 (32%)

GP 3 (11%)

*Patients could select one or more categories.

are shown in Table III. Amongst those choosing methadone 64% cited past experience (either good with methadone or bad with buprenorphine) as a reason for their choice, in contrast only 25% of the buprenorphine group referred to previous experience. Anticipated effects of the drug (greater intoxication for methadone and the opiate blocking effect, reduced craving, clear-headedness and easier detoxification for buprenorphine) were cited as a reason for choice far more frequently by the group choosing buprenorphine (81% responses from the buprenorphine group vs. 14% responses from the methadone group,

p,0.001).

Table II. Comparison of participants views of buprenorphine and methadone (n529) Patients’ views of

Buprenorphine, mean VAS{_score

(median)

Patients’ views of methadone, mean VAS{_score

(median)

Comparing individuals’ views of the two drugs

(Wilcoxon signed rank test)

Taste(15awful to 55great) 2.1 (1) 2.9 (3) p50.04*

Withdrawal symptoms at induction

(15not at all to 55yes, very badly)

3.3 (3) 2.6 (3) p50.13

Prevention of withdrawal on maintenance

(15very badly to 55very well)

4.6 (5) 4.6 (5) p51.00

Effect on craving(15no effect to 55great) 3.8 (4) 2.9 (3) p50.01 *

Blocking of effect of heroin(15nil to 55totally blocked)

4.8 (5) 1.6 (1) p,0.0001**

Risk of fatal overdose(15very high to 55

very low)

3.8 (5) 1.5 (1) p50.0095*

Clear-headedness(15very to 55not at all) 1.5 (1) 2.9 (3) p50.0002**

Sedation(15very sleepy to 55very awake) 4.3 (5) 2.4 (2) p50.0001 **

Numbing of emotional reactivity(15none at all to 55disconnected)

1.9 (1) 3.1 (3) p50.0003**

Stigma(15stigmatized to 55no problem) 3.2 (3.5) 2.4 (1) p50.0892

Ease of detoxification(15easy to 55very hard)

2.3 (2) 4.1 (4) p50.0003 **

Treatment seen as an alternative addiction(15very true to 55not true)

3.4 (3.5) 2.1 (1) p50.004*

Expected length of detoxification(3-point scale, 15days, 25weeks, 35months)

2.3 (2) 2.9 (3) p50.0017*

{_{VAS5visual analogue score.}

*p,0.05 (possibly significant given large number of comparisons).

**p,0.001 (likely to be significant despite the large number of comparisons).

Table III. Reasons given for choice of maintenance drug Reasons given by methadone group and numbers providing reason (%) (n522 participants giving 22 responses)

Reasons given by buprenorphine group and numbers providing reason (%) (n520 participants giving 26 responses)

Good experience with methadone: 10 (46%) Blocking effect: 10 (50%) Bad experience with buprenorphine: 4 (18%) Easier to come off - 5 (25%) Wanting a level of intoxication: 3 (14%) Reduced craving: 4 (20%) Believes using too much heroin to have buprenorphine:

3 (14%)

Bad experience with methadone: 3 (15%) Wish to continue using heroin: 1 (5%) Good experience with buprenorphine: 2 (10%) Would see ‘blocker’ effect as a challenge: 1 (5%) Clear headedness: 2 (10%)

*Some participants cited more than one reason.

Table IV reveals the two groups’ other comments about methadone and buprenorphine. In general, the group choosing methadone tended to express moderate, pragmatic views (‘not sure it’s the answer but it helps to keep stable’, ‘does the job’) about both drugs whereas those choosing buprenorphine tended to express more extreme views, often very negative about methadone (‘evil-should be banned’) and very positive about buprenor-phine (‘wonder drug’).

In line with the results from the visual analogue scale participants mentioned the clear-headedness achieved with buprenorphine, although this was not considered necessarily a good thing by those choosing methadone (‘made everything too bright’). Faith in the ‘blocking effect’ was an important factor for some who seemed to equate this with a guarantee that they would not only cease heroin use, but in some cases also cease to crave heroin. Several in this group expressed the view ‘everyone on methadone is still using (heroin)’, in contrast to those on buprenorphine. Indeed, there were a few in the methadone group who admitted they were not yet ready to give up heroin use and cited this as a reason not to choose buprenorphine, but this did not appear to be common.

The potential for experiencing withdrawals during induction was commented on by the methadone group, but not those choosing buprenorphine. At the other end of treatment the long withdrawal from methadone and easier withdrawal from buprenorphine were repeatedly mentioned by both groups as a clear advantage of buprenorphine and this was cited as a reason for their choice by 25% of the group choosing buprenorphine.

Discussion

This study has revealed that substance users are relatively well informed about methadone and buprenorphine and that those choosing methadone and buprenorphine appeared to have very similar beliefs about the two drugs. Despite this they made different choices. The differences both groups identified that could have formed the basis for a decision between the two drugs were as follows. In comparison with methadone, buprenorphine was regarded as less familiar, but more effective at blocking the effect of heroin; easier to withdraw from and less intoxicating. Buprenorphine may also be seen as more effective at reducing craving for heroin, safer in overdose and representing less of an ‘alternative addiction’, although it has a more unpleasant taste. How these beliefs were used to come to a decision appears to depend on the priorities and requirements of different individuals.

The commonest reason for choosing methadone was familiarity and a good personal experience with the drug, whereas the majority of those choosing buprenorphine cited properties of the drug that they considered appealing, most commonly the increased opiate receptor block.

Further comments revealed that the group choosing buprenorphine tended to express more extreme views than those choosing methadone. Given that this group tended to be older with a longer history of addiction, but were less likely to have had a maintenance prescription (especially methadone) before and more likely to have been to a residential rehabilitation centre (which are primarily abstinence based) it seems possible that their dislike of methadone may have been long standing and have prevented previous engagement with community treatment services. The widespread belief amongst the buprenorphine group that those on methadone would still use heroin (in contrast to themselves) suggested that they believed buprenorphine to be the drug of choice for those ‘serious’ about treatment. Equally, the relative ease of withdrawal from buprenorphine appeared a reasonably prominent reason for choosing this drug.

Examples of comments about methadone Examples of comments about buprenorphine

Group choosing methadone Group choosing buprenorphine Group choosing methadone Group choosing buprenorphine General positive

Comments

‘Not sure it is the answer, but it helps to keep stable’, Know what to expect - can work, run life, family etc’, ‘Been on it before’

‘A lot of people are very happy on it’, ‘Good’, ‘Other people like it’

‘Wonder drug’, ‘Good as gold’, ‘Healthier’, ‘Cleaner’, ‘Would give subutex 10/10 and recom mend it to anyone’

General negative comments

‘People say it’s bad’, ‘Swapping one addiction for another’

‘Nasty stuff’, ‘Nightmare’, ‘Evil’, ‘Shite’, ‘should be banned’, ‘more addictive than gear’, ‘Same as heroin—want to get away from that scene

‘Tastes horrible’, ‘Can IV it’, ‘Artificial’, ‘Small tablet -can’t psychologically believe it would work’

‘Makes the tip of your tongue go numb’

Dose titration ‘The titration’s difficult’, ‘Have

to go through withdrawals to get on it’, ‘Others say its good but the first few weeks are bad’, ‘Can’t get on it from high doses’ Prevention of

with-drawal symptoms

‘Stops you feeling ill’, ‘Holds you well’, ‘Stops you clucking’

‘Wears off quickly - doesn’t hold you’, ‘Doesn’t hold you through 24 h’

‘Stops withdrawals’, ‘Does the job’

‘Holds you well for 24 h’

Clear-headedness vs. intoxication

‘Takes emotions away’, ‘Blanks things out’, ‘More comfortable’, ‘A cushion’, ‘Sleep well’, ‘Not drowsy’

‘Makes you drowsy’, ‘Makes you feel sick’

‘Makes you feel straight’, ‘More ‘alert’ drug’, ‘Wide awake’, ‘made everything too bright’

‘Function well on it’, ‘Can work on it’, ‘Clear-headed enough to work’, ‘Feel more confident taking it’, ‘No drowsiness -not like methadone’ Comments about

blocking effects/ craving/on top use

‘Doesn’t stop urge for iv use’ ‘Can use on top’, ‘Everybody I know on methadone uses heroin’, ‘Still want gear when I’m on methadone’

‘Blocks heroin use’, ‘Blocks receptors’, ‘Blocker’, ‘Blocks heroin use’, ‘Stops the craving for heroin’, ‘Stops craving for heroin but not for iv use’

‘Blocking effect stops your craving for all drugs’, ‘Blocker so you can’t carry on using’, ‘Feel ill if use gear’, ‘Everybody I know on Subutex doesn’t use heroin’, ‘Antagonist as well’ Coming off ‘Worse than heroin to come

off’, ‘Bad withdrawals when come off’

‘Cant get off it’, ‘Worse than’ heroin to come off’, ‘Horrible to come off’, ‘Long miserable withdrawal

Other ‘Weight gain’ ‘Eats at your bones ‘, ‘Gets in your bones and rots your teeth’, ‘Puts holes in your bones’

Sur vey of pat ients view s about opia te maintena nce 151

The lack of intoxication with buprenorphine was viewed positively by those preferring it but negatively by others. This may reflect differing requirements. One hypothesis is that those with higher levels of psychological discomfort or insomnia may function better with the more sedating drug (‘sleep well’, ‘blanks things out’). Participants were also aware of potential differences regarding risk of fatal overdose, but none cited this as a reason underlying their choice of drug, reflecting perhaps the ambivalence of this group towards safety and contrasting with the views of health professionals (Luty, O’Gara, & Sessay, 2005).

Myths expressed that are not supported by research were generally negative about methadone and positive regarding buprenorphine in both groups. The idea that methadone ‘rots your teeth and bones’ seems to be particularly resistant to change as it is reported in research back as far as the 1970s (Brown, Benn & Jansen, 1975). As in previous studies this seemed to affect individuals preparedness to receive methadone therapy (Fischer et al., 2002; Rosenblumet al., 1991; Stancliff, Myers, Steiner & Drucker, 2002). Another belief was that buprenorphine suppresses craving more than methadone. Again this belief is not supported by the literature (Pani, Maremmani, Pirastu, & Tagliamonte, 2000; Petitjean, Stohler, Deglon, Livoti, Waldvogel, Uehlinger, & Ladewig, 2001). However, local experience suggests that, for some, faith in the blocking effect of buprenorphine does seem to help to reduce the drive to use illicit heroin.

In summary, these data give a preliminary insight in to the views of substance users about methadone and buprenorphine. Our findings suggest that opiate dependent individuals presenting for maintenance treatment are well informed about the drugs available for treatment and hold strong views as to which they prefer to receive. This level of knowledge and the development of preferences appears to occur within a relatively short period of time after a new drug becomes locally available. These choices do not appear to be based on different beliefs about the drugs but on the different personal priorities of the individuals concerned. Additionally, the data support the hypothesis that some in the group choosing buprenorphine were averse to treatment with methadone and that this may have prevented their engagement with treatment, hence, the availability of an alternative could be an aid to recruiting opiate users into treatment with potential gains for that individual’s health and to society more generally.

Acknowledgements

We are grateful to the Norfolk Primary Care Trusts for funding this study, which would have been impossible to complete without the co-operation of the staff at the Bure Centre Unthank Road and Colegate. Particular thanks go to Vivienne Maskrey, Roz Brooks and Clive Rennie

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