Research Roundup Summer 14

Welcome to the latest research roundup from the Addiction Research Group based in the Department of Psychological Sciences, University of Liverpool. Summer has come and gone, but don’t let it dampen your spirits because here is our quarterly feast of science for your enjoyment!  

Top billing goes to Inge Kersbergen and Matt Field who published a paper in Psychology of Addictive Behaviours examining the validity of different measures of automatic alcohol action tendencies.  The aim of this study was to compare different tasks that measure automatic alcohol-approach biases on their ability to predict individual differences in drinking behaviour. The results demonstrated  that only the tasks in which participants had to respond to the pictures based on their content (alcohol or control) rather than an irrelevant feature (picture orientation) were significant predictors of drinking behaviour. On the relevant-feature tasks, faster approach responses to alcohol pictures were related to higher levels of risky drinking and alcohol consumption.  This study was the first to compare these different types of tasks and it has important implications for the development of approach bias modification training in clinical populations. 

A second paper, by Eric Robinson and colleagues published in Appetite set out to examine how a laboratory environment influences how much food people eat. In particular, we wanted to know whether people eat less when they believe that a researcher is going to record and monitor their food consumption. We sampled a group of young females and found that participants ate less food when they felt as though their behaviour was being monitored. We think this study raises an important question about how we should study eating behaviour. Although getting participants into a lab can help us to control external influences and observe exactly what they do, this might come at the cost of affecting and changing the very behaviour we are trying to study. We will be following this study up over the next few months and should have more answers soon!

Samantha Baker (a clinical psychology trainee), Joanne Dickson and Matt Field published a paper in BMC Psychology examining whether implicit priming of approach or avoidance motivational orientations influenced the opposing orientation.  In a group of non-dependent drinkers subliminal word primes were presented during trials of visual probe and stimulus-response compatibility tasks.  These primes were alcohol-appetitive (e.g Party), alcohol-aversive (e.g. nausea) or neutral (e.g. bookshelf).  Contrary to expectations, we found no effects of masked priming of motivational orientations on attentional bias for alcohol cues, or on automatic approach and avoidance tendencies evoked by those cues. These results tentatively suggest that automatic alcohol cognitions cannot be influenced by subliminal priming. 

Matt Field, Andy Jones, and Abi Rose contributed to a series of experiments published in Behaviour Research and Therapy that identified an important role for propositional knowledge in responses to drug cues, including Pavlovian to Instrumental transfer effects (these effects were covered in an earlier blog). 

Finally, we published our first ever study protocol in BMC Public Health, describing the procedure and analysis plans for an ongoing controlled trial on web-based inhibition training for problem drinkers. This study is the first to examine repeated inhibition-training for the reduction of problem drinking in community samples. We believe that publishing these protocols is important as it encourages transparency when reporting results from large scale research studies. 

We have been on our travels again, disseminating our research around the UK (and beyond)!

Andy and Matt travelled to Stirling in May, for an ESRC workshop aimed at increasing the richness and frequency of social science survey data. Andy discussed the use of smartphones to administer cognitive tasks.

A whole gang of PhD students and early career researchers travelled to Leeds in June for an early career event organised by the UK Centre for Tobacco and Alcohol Studies (UKCTAS). This was followed by a Public Health Research Centres of Excellence Conference, in which both Inge Kersbergen and Eric Robinson gave presentations on their research conducted at Liverpool. 

We also attended the British Association for Psychopharmacology meeting and a satellite symposium organised by the International Society for Research on Impulsivity in Cambridge in June. At the meeting Andy Jones received the Junior BAP/Cambridge Cognition award for his research. Well done to him! 

Matt Field gave a keynote lecture at the British Association for Behavioural and Cognitive Therapy entitled ‘Cognitive processes in addiction: new directions and clinical implications’. Together with Frank Ryan (Imperial College London), he also ran a pre-conference workshop for therapists on ‘Thinking the way out of addiction’.

Finally, Matt and Andy attended the 5^th Thematic Meeting on Addiction in Utrecht, Netherlands. Matt discussed the Effects of inhibition training on alcohol intake in problem drinkers.

We have contributed articles for the Mental Elf about cytisine and varenicline for smoking cessation, internet-based drug prevention, and mobile apps for recovering alcoholics. Natasha Clarke has also written some excellent blogs spanning world cup alcohol advertising to ‘nudge’ interventions.

There have also been some comings and goings in our research group. 

Three new PhD students have joined our group: Graeme Knibb, Panos Spanakis and Mrunal Bandawar. Finally, we say goodbye and good luck to Elly McGrath who left her research position with us to begin her PhD at Manchester.

That’s all we have. Thanks for reading. As always, if you would like to get in touch about anything featured here please contact Prof. Matt Field, and if you are interested in taking part in our research please contact Andy Jones

Internet-based interventions for harmful drinking show small beneficial effects

This post was originally written by Andrew Jones for the Mental Elf. You can see the original here.

According to the World HEALTH Organisation (WHO), alcohol misuse ranks within the top ten HEALTH conditions with the highest burden of disease. The prevalence of hazardous and harmful drinking in the UK is approximately 7.6 million people. The health implications of such drinking patterns can be severe and there is increased risk of progression to dependence if not treated.

Research suggests that the majority of hazardous drinkers would like support to reduce their drinking, however they would prefer help outside of conventional health-care settings. Furthermore, these individuals are unlikely to engage with abstinence-based treatments and thus controlled drinking is a more realistic goal. Individuals often remain hidden to conventional treatments because of these factors. However, internet self-help interventions appear to be a promising strategy in overcoming this treatment gap.

Internet-based interventions for harmful drinking

Studies of web-based interventions suggest they reach first time help seekers, and are taken up much more readily than low-intensity face-to-face interventions. Most of these interventions are unguided and delivered as standalone procedures in the community. A previous meta-analysis focusing on these unguided interventions reported significant reductions in alcohol consumption, compared to control groups (Riper et al, 2011).

Recently there has been increased research into these unguided internet-based interventions, but also interventions that are therapist-led (guided). As a result, a meta-analysis published in PLoS ONE set out to examine the effectiveness of both guided and unguided low-intensity internet interventions for adult alcohol misuse (Riper et al, 2014).

Previous studies have reported significant reductions in alcohol consumption from unguided Internet-based interventions

Methods

The authors conducted a literature search in bibliographic databases up until September 2013. In order to be included in the analysis, studies had to compare a web-based intervention with a control group (e.g. a waitlist or alcohol information brochure) and include a low-intensity self-help intervention that could be performed on a COMPUTER or mobile phone, with or without professional guidance. Studies also had to include drinkers who exceeded guidelines for low-risk drinking and include an assessment of drinking behaviour as a primary outcome measure.

The authors identified 16 studies (containing 23 comparisons) for their meta-analysis. The studies included 5,612 PARTICIPANTS (3,268 in intervention and 2,344 in control / comparison conditions). This allowed the authors to detect the small effect size which they were expecting.  All studies included were published fairly recently, between 2006 and 2013.

Results

• The effect of low-intensity internet-based alcohol interventions to reduce alcohol consumption in comparison to controls was significant at post-test (g=0.20; 95% CI: 0.13 to 0.27, p<.001, NNT=8.93).
• PARTICIPANTS in a guided or unguided intervention group drank significantly less units per week at post-treatment than controls (n =14; 2.2 units; 95% CI: 0.87 to 3.46, p = .001). On average, intervention participants were drinking 22 grams of alcohol less per week. A standard UK unit is 8 grams compared to 10 grams in the Netherlands (where the meta-analysis was conducted), so this is approximately a pint of beer or glass of wine per week (i.e. not an awful lot!).
• Compared to controls, intervention participants were more likely to have reduced their alcohol consumption to within low risk-guidelines (n = 6; RD 0.13, 95% CI: 0.09 to 0.17, p<.001).
• At 6-12 month follow-ups there were no significant differences between six unguided interventions and control groups (g = 0.06, 95% CI: -0.14 to 0.25, p = .567). There were no follow-up data available for guided interventions.
• There was no significant difference in effect sizes between guided (g = 0.23) and unguided (g = 0.20) alcohol interventions.

On average, the guided or unguided intervention group members drank about a pint of beer or glass of wine less per week

Conclusions

This meta-analysis demonstrated a small but significant effect in favour of low-intensity internet-based self-help interventions for alcohol misuse. The results of this study support the use of internet-based self-help interventions for curbing alcohol use in various settings.

Although the pooled effect of the interventions was small, the authors suggest that:

The public HEALTH impact could be substantial if large numbers of people who misuse alcohol were to take part in these interventions.

Whilst these results seem promising, it is worth noting that the reduction of 22 grams of alcohol is lower than that of face-to-face interventions in primary care, and also lower than a previous meta-analysis focusing on unguided interventions only (Kaner, et al, 2007).

Limitations

The findings of this study should be interpreted with some caution, as there are some limitations:

• The subgroup analyses comparing guided to unguided interventions suffered from a lack of power
• Also, some studies reported high dropout rates (up to 42%), however this is a common occurrence in internet-based research

Future research in this area should focus on longer follow-ups to assess the maintenance of intervention effects, and also direct comparisons between guided and unguided interventions.

To conclude, low-intensity internet-based self-help interventions may be beneficial in reducing alcohol use and these interventions may provide a cost effective way of bridging the treatment gap in hazardous drinkers.

Future studies need to follow-up people for longer and compare the differences between guided and unguided interventions.

Links

Riper, H., Blankers, M., Hadiwijaya, H., et al (2014). Effectiveness of Guided and Unguided Low-Intensity Internet Interventions for Adult Alcohol Misuse: A Meta-Analysis. PLoS ONE, 9(6): e99912.

Kaner EF, Dickinson HO, Beyer FR, Campbell F, Schlesinger C, Heather N, Saunders JB, Burnand B, Pienaar ED. Effectiveness of brief alcohol interventions in primary care populations. Cochrane Database of Systematic Reviews 2007, Issue 2. Art. No.: CD004148. DOI: 10.1002/14651858.CD004148.pub3.

Riper, H., Spek, V., Boon, B., et al (2011). Effectiveness of E-self-help interventions for curbing adult problem drinking: a meta-analysis. J Med Internet Res, 12(2):e42.

Should we be prescribing medication to help people with alcohol use disorders?

This post was originally written by Andrew Jones for the Mental Elf. You can see the original here.

Alcohol Use Disorders (AUDs) are common, chronic conditions which cause substantial harm to the individual and society. They are associated with substantial morbidity (Schuckit, 2009) and responsible for approximately 4% of all deaths annually. The approximate cost of AUDs to the National HEALTH Service is upwards of £3 billion per year.

Less than one-third of patients with AUDs will receive any treatment and an even smaller number (<10%) will be prescribed medications to assist in reducing their alcohol use. There are a number of FDA approved medications for AUDs such as acamprosate, disulfiram and naltrexone. However, various barriers exist for health-care professionals prescribing these medications including a lack of familiarity and a lack of confidence in their effectiveness.

A recent systematic review and meta-analysis published in the Journal of the American Medical Association, set out to examine the benefits and harms of pharmacotherapy for adults with AUDs (Jones et al, 2014).

Methods

The authors searched databases (including the Cochrane Library, Pubmed etc) for relevant studies from January 1^st 1970 to October 11, 2013. They also searched for unpublished studies using various trial registration platforms and requested data from medication manufacturers.

In order to be included in the analyses studies had to include adults with AUDs who were treated with an FDA approved or off-label medication for at least 12 weeks in an outpatient setting. The studies were required to assess either:

1. Alcohol consumption,
2. HEALTH outcomes (i.e. accidents, mortality etc), or
3. Adverse effects of the medication.

Results

One hundred and twenty three studies were included in the meta-analysis, with a total of 22,803 PARTICIPANTS. All the studies except one were randomised controlled trials. The majority of the studies assessed acamprosate or naltrexone alone or in combination with repeated behavioural interventions.

Both acamprosate and naltrexone were associated with complete abstinence from alcohol

Consumption measures

• Acamprosate was associated with:
  • An increase in total abstinence from drinking (Number needed to treat (NNT) = 12, 95% Confidence Interval (CI) 8 to 26; Risk difference (RD) -0.09; 95%CI, -0.14 to -0.04)
  • But not in abstinence from heavy drinking
• Oral naltrexone was also associated with:
  • An improvement in total abstinence from drinking (NNT = 20, 95% CI, 11 to 500; RD, -0.05; 95%CI -0.10 to -0.002)
  • Abstinence from heavy drinking (NNT = 12, 95% CI, 8 to 26; RD -0.09; 95%CI, -0.13 to -0.04)
• Injectable naltrexone was only associated with a reduction in heavy drinking days (Weighted Mean Difference = -4.6%, 95% CI, -8.5% to -0.56%)
• A comparison between acamprosate and naltrexone found no statistically significant differences between the two medications on alcohol consumption measures
• Disulfiram demonstrated no significant improvements in alcohol consumption measures
• There was some evidence that off-label drugs such as nalmefene and topiramate were associated with reductions in alcohol consumption measures (fewer heavy drinking days)

Health outcomes

There was insufficient evidence to examine whether treatments lead to an improvement in HEALTH outcomes.

Adverse effects

Again, there was insufficient evidence to examine potential adverse effects. However, the authors noted that for most of the specific adverse effects in head-to-head studies, estimates favoured placebo.

Do these results give clinicians and patients the evidence they need to make prescribing decisions?

Conclusions

The use of pharmacotherapy as a TREATMENT FOR AUDs is underutilized (Harris et al, 2010) but may lead to clinically beneficial results. Both acamprosate and naltrexone were associated with complete abstinence from alcohol, and naltrexone was also associated with a reduction in heavy drinking days. There was also some limited evidence for off-label prescriptions of topiramate and nalmefene.

A recent commentary (Bradley et al, 2014) suggests that ‘no single treatment is superior to all others’ and many health-care professionals do not fully explore the treatment options for AUDs. These findings demonstrate that patients should be offered individual treatment options, including medications shown to be effective through evidence.

There are some limitations to the current research. Only trials with at least 12 weeks of treatment were eligible. However, such short treatment periods may yield misleading conclusions about benefits in the long term. Furthermore, the authors suggest that most studies included were at a moderate risk of bias, i.e. selective or incomplete reporting of important variables within studies.

In conclusion, the authors suggest their findings have the potential to inform clinicians and health-care providers who are reluctant to prescribe medication for AUDs. Future research should focus on establishing the efficacy of pharmacotherapy for AUDs in patients for which controlled-drinking, rather than complete abstinence, is a realistic goal.

Links

Jones, D.E., Amick, H.R., Feltner, C., et al (2014). Pharmacotherapy for adults with alcohol use disorders in outpatient settings: a systematic review and meta-analysis. The Journal of the American Medical Association, 311(18), 1889-900.

Bradley, K.A., Kivlahan, D.R. (2014). Bringing patient-centered care to patients with alcohol use disorders. The Journal of the American Medical Association, 311(18), 1861-2

Harris, A.H., Kivlahan, D.R., Bowe, T., Humphreys, K.N. (2010). Pharmacotherapy of alcohol use disorders in the Veterans Health Administration. Psychiatric Services, 61(4), 392-8.

Schuckit, M. Alcohol-use disorders. Lancet, 2009 Feb 7, 373 (9662), 492-501.

Research Roundup Spring 2014

Welcome to the latest research roundup from the Addiction Research Group based in the Department of Psychological Sciences, University of Liverpool. As ever, we have been working hard over the past few months on many different research topics, and in this blog post we have condensed some of our recent publications and activities into bite-size portions for your enjoyment. 

The first two publications reported investigations of how our drinking behaviour is influenced by that of other people.

A study conducted in our bar lab was published in Alcoholism: Clinical and Experimental Research. We examined how social acquaintances influence each other’s alcohol consumption using a confederate design. A pair of social drinkers was invited to the laboratory, and one of them (the confederate) was secretly informed to choose either alcoholic or soft drinks when offered them by the experimenter. Both individuals were subsequently offered drinks to consume while they played a game together (the popular ‘4 pics 1 word’ game). The key variable of interest was the amount of alcohol that the naïve participant chose to consume. We found that naïve participants were strongly influenced by their acquaintance’s choice: if the confederate chose alcoholic drinks, the naïve participant was much more likely to choose them as well. Furthermore, the majority of participants believed that their drinking was not influenced by their partner’s choices. This study was the first to use the confederate design in individuals who knew each other before the study, and it has important implications for the psychological mechanisms that underlie effects of imitation on drinking behaviour. The study was conducted by Rebecca Dallas, an undergraduate psychology student who is first author on the paper. The paper was the topic of a press release and it was covered by several print and online media outlets, including the Metro and science website RedOrbit.  The research was also covered by some other unexpected news sources, including ‘RealBollywood’, which surprised and excited us (mostly the former).  

The second paper, by Eric Robinson and colleagues, was published in Substance Use and Misuse. This Internet study investigated if there is an association between perceived drinking norms and usual drinking behaviour in UK students.  We also included interventions to correct misperceptions about the drinking behaviour of others, and increase intentions to drink responsibly. We found that peer drinking was associated with individual differences in drinking: individuals who believed other students drank responsibly also drank responsibly. However, interventions based on accurate norm messages did not influence intentions to drink responsibly, possibly because they were not seen as credible. This study adds to a growing literature suggesting that social norm interventions may have limited efficacy in reducing hazardous drinking in UK students.  

Speaking of bite-size portions, we have diversified from only studying alcohol. We recently published two papers that examined the motivation to obtain and consume chocolate and pizza. 

The first paper by Charlotte Hardman and colleagues was published in Appetite. This research continued previous work by our group (see here and here) examining whether the anticipation of receiving a reward, in this case delicious cheese and tomato pizza, would influence physiological (salivation) and attentional responses in hungry participants. Whilst there was no evidence for any effects of anticipation on salivation, we demonstrated that anticipation influenced initial attentional processing of pizza pictures. While this result wasn’t quite as clear cut as our previous studies with beer and chocolate, it does suggest that anticipation of reward plays a role in attentional bias for rewarding cues.  

Our second snack-themed paper was published by Jessica Werthmann, Matt Field and colleagues in Journal of Behavior Therapy and Experimental Psychiatry. In this study we examined whether manipulating attention towards or away from chocolate using a modified anti-saccade task could influence craving and consumption of chocolate. We found that participants who shifted attention towards chocolate cues subsequently ate more chocolate during an ad-libitum taste test compared to those shifted their attention away from chocolate.  These findings suggest that training attentional bias away from food-cues can reduce consumption of that food, although in other papers we have been sceptical about the clinical applications of ‘attentional bias modification’, particularly in addiction.

Last but no means least, Jasna Martinovic and colleagues published a paper in PLoS One (we support open access!). In this study we examined electrophysiological correlates of Pavlovian-to-Instrumental transfer (PIT) in individuals who regularly drink beer and eat chocolate. PIT is the phenomenon whereby drug-cues evoke an anticipation of drug reward and thereby increase instrumental responding for drug reward. The brain mechanisms that underlie PIT effects are poorly understood and this was the focus of this study. We examined whether electrophysiological indices of the motivational salience of beer and chocolate pictures (the P300 and Slow Potential) would be associated with behavioural PIT responses for beer and chocolate rewards. We found clear behavioural PIT effects and some indication of increased Slow Potentials in response to the beer and chocolate pictures, but unfortunately these were not related to each other. Possibly, behavioural PIT effects are generated by subcortical structures that cannot be detected using EEG, or maybe we just didn’t use the right method. 

As well as writing papers we also like to get out and see the world, all in the name of science of course...

Inge Kersbergen, Jay Duckworth and Natasha Clarke attended Alcohol Research UK’s first postgraduate and early career symposium in London in March. Natasha and Inge both gave oral presentations. Inge presented her own study, ‘Visual attention to health information on alcoholic drinks containers’ which was an eye-tracking study examining responses to warning labels on alcohol drinks containers, and Natasha presented the paper, ‘Alcohol-induced risk taking on the BART mediates alcohol priming’ which we discussed in a previous roundup. 

Matt Field discussed the role of attentional bias in addiction at the ‘Maastricht symposium on the role of attentional bias in psychopathology’, in March. After the conference, our former (temporary) colleague Jessica Werthmann successfully defended her PhD thesis, for which we offer our congratulations!!

That is all for this research roundup. Thank you for reading! As always, if you would like to get in touch about anything featured here please contact Prof. Matt Field, and if you are interested in taking part in our research please contact Andy Jones