Key study : Grant et al (2008) Flashcards
(11 cards)
What is the aim of the key study by Grant et al?
To identify clinical variables associated with treatment outcomes in problem gambling patients receiving opiate antagonists.
What were the hypotheses used to test the aim in the study by Grant et al?
1) A family history of alcoholism and stronger urges to gamble would be associated with positive outcomes for those treated with opiate antagonists.
2) People with less severe problem gambling would be more likely to positively respond to a placebo than those with more severe problem gambling.
What is the sample in the study by Grant et al?
- 284 patients
- 137 female, 147 male who have gambled two weeks prior to the enrollment
- They all meet the DSM-5 criteria for problem gambling
- 235 were Caucasian, 24 African-American, and 20 others.
- There were 207 outpatients from 15 psychiatric centers who participated in a 16 week trial of nalmefene
- There were 77 participants in a 18 week trial of naltrexone
Describe the experimental design in the study by Grant et al.
-Two medical conditions were used in the experimental group ;
a multi-centre 16 week trial of nalmafene, patients were from 15 outpatient psychiatric treatment centres in the US
- A single site 18 week trial of naltrexone.
–The participants were randomly assigned to either group, placebo or experimental.
- A double blind placebo control trial was used as both the researchers and the participants did not know who was in the placebo group.
-Participants were randomly assigned to either the placebo group or the low, medium or higher doses in the drug group.
-
What were the two medications used in the experimental group?
Multi-center 16-week trial of nalmefene (15 outpatient psychiatric treatment centers in the US). A single site 18-week trial of naltrexone, University of Minnesota.
What was the inclusion criteria in the study by Grant et al?
Meet the DSM-4 criteria for PG. A score of 5 or more on the South Oaks Gambling Screen. Having gambled within 2 weeks prior to the involvement.
What is the exclusion criteria in the study by Grant et al?
- Infrequent gambling (less than 1 time per week)
- Unstable mental illness or clinically significant abnormalities.
- Current pregnancy or lactation.
- Lifetime history of Bipolar type 1 or type 2.
- Dementia, schizo or any other psychotic disorder.
- Current DSM for substance abuse.
- Clinically significant suicidality.
- Previous treatment with nalmefene, naltrexone.
How was random assignment done in the study by Grant et al?
Was done in blocks of 8 using computer generated randomization, to one of the four conditions to either nalmefene or naltrexone.
The conditions are:
Nalmefene:
- Placebo
- 25 mg/day
- 50 mg/day
- 100 mg/day.
Naltrexone:
- Placebo
- 50 mg/day
- 100 mg/day
- 150 mg/day.
What were the outcome measures used?
Comorbid (co-occurring conditions) diagnosis was assessed using clinical structured interviews for DSM-4.
Family history assessment was performed using semi-structured interviews. The primary outcome measure was PG-YBOCS (problem gambling - Yale Brown Obsessive Compulsive Scale modified for problem gambling).
PG-YBOCS measures:
1. Gambling urge.
2. Gambling behaviour.
It has 10 items, 5 items comprise the gambling urge subscale and the other 5 comprise the gambling behaviour subscale.
Secondary measures include:
- Sheehan disability scale.
- Hamilton anxiety rating scale (HAM-A).
- Hamilton depression rating scale (HAM-D).
Results from the study by Grant?
- Treatment response was defined as at least 35% reduction in PG-YBOCS total score for at least one month following treatments.
- The variable most strongly associated with a positive response to an opiate antagonist was a positive family history of alcoholism.
- There might be a genetic influence on the response to opiate antagonist treatment.
- Those with less severe problem gambling did not respond more positively to a placebo.
Conclusion from the study by Grant?
A family history of alcoholism and strong gambling urges seem to predict a positive response to opiate antagonists in the treatment of problem gambling.
