Nicotine Dependence
Conditions
Keywords
Nicotine dependence, cigarette, smoking, nicotine replacement therapy, positron emission tomography
Brief summary
The proposed research will provide significant new gender-specific information of scientific and clinical relevance on the function of the mu-opioid system in nicotine dependence and therapeutic effectiveness of nicotine replacement therapy (NRT). The studies will help to explain the differences in the prevalence of smoking in men and women, sex-specific differences in nicotine craving and withdrawal as well as the poorer therapeutic response to NRT. This work may pave the way to the design of improved pharmacotherapies that can more effectively target the endogenous opioid system in the treatment of nicotine dependence.
Detailed description
While smoking prevalence has declined for both men and women over the last two decades, rates among women have shown a much shallower decrease and, in recent years, prevalence of cigarette initiation has been higher for girls than boys. Smoking among women of child-bearing age has significant negative health consequences for mother and child, increasing fetal and infant morbidity and mortality. Women are both less likely to initiate a quit attempt and more likely to relapse if these women do quit. Nicotine replacement therapy (NRT), still the most widely used smoking treatment intervention in the United States, is less effective for women compared with men, and women report less craving reduction on NRT. The endogenous opioid system is involved in smoking initiation, nicotine craving and reward as well as nicotine withdrawal symptoms. Interestingly, research suggests that sexual dimorphic features of the endogenous mu-opioid system may in part explain gender differences in nicotine effects. To better understand the role of the mu-opioid system in poorer NRT responses in women, this proposal will examine NRT effects on mu opioid receptor binding potential (MOR BP) in female compared to male smokers during active versus placebo NRT. Specifically, nicotine dependent women and men in active smoking status will undergo PET imaging for MOR BP measurement using 11C-carfentanil. Following baseline PET measurement in active smoking (scan 1), smokers will be randomized to active or placebo nicotine replacement therapy ((A-NRT or P-NRT); 72 hours later, a second scan will be obtained. As a reference group, demographically-matched women and men who have never smoked will undergo two scans as well. Behavioral measurements of nicotine reward, craving and withdrawal will be obtained repeatedly across the protocol. The proposed research will provide significant new, gender-specific information of scientific and clinical relevance on the function of the mu-opioid system in nicotine dependence and therapeutic effectiveness of nicotine replacement therapy.
Interventions
21 mg patch
Sponsors
Study design
Eligibility
Inclusion criteria
* 21 - 60 years old * must meet DSM-IV criteria for nicotine dependence and be actively smoking
Exclusion criteria
subjects must meet study guidelines for medical and mental health status.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | 90 minutes | BP provides an estimate of the product of the density of available receptors (Bmax' or the receptor density Bmax less those occupied by endogenous transmitters) and the affinity \[1/equilibrium dissociation constant (KD)\]. We use reference tissue graphical analysis (RTGA) to obtain regional BP values using occipital lobe as a reference region. Negative BP change means means a decrease in the BP and positive BP change means an increase in the BP. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Relationship Between Change in Mu-opioid Receptor Binding Potential and Visual Analog Craving Scale Score | 72 hours | Regression measure (β) between change in mu-opioid receptor binding potential between baseline scan and post-treatment scan in the left amygdala and mean Craving Visual Analog Scale score on Days 2 - 4 of the Clinical Research Unit stay. Craving visual analog scale ranges from 0 (not at all) to 20 (worst ever). |
| Relationship Between Change in Mu-opioid Receptor Binding Potential and Minnesota Nicotine Withdrawal Scale Score | 72 hours | Regression measure (β) between change in mu-opioid receptor binding potential between baseline scan and post-treatment scan and mean Minnesota Nicotine Withdrawal Scale (MNWS) score on Days 2 - 4 of the Clinical Research Unit stay. The MNWS is a self-report measure that consists of 14 nicotine withdrawal symptoms each rated on a 0 - 4 response scale for severity over the past 24 hours. Higher scores are indicative of greater nicotine withdrawal severity. |
Countries
United States
Participant flow
Pre-assignment details
102 of the participants who passed the on-phone screen came in and signed the consent form to be enrolled in the study. Baseline characteristics data was collected from them but they however failed an assessment done prior to getting the PET scan and so could not start the study.
Participants by arm
| Arm | Count |
|---|---|
| Nicotine Patch - Transdermal 21 mg nicotine patch
Nicotine patch - transdermal | 42 |
| Placebo NRT Matching placebo patch
placebo | 42 |
| Healthy Non-smoker Comparison Demographically-matched women and men who have never smoked | 43 |
| Total | 127 |
Baseline characteristics
| Characteristic | Nicotine Patch - Transdermal | Placebo NRT | Healthy Non-smoker Comparison | Total |
|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 42 Participants | 42 Participants | 43 Participants | 127 Participants |
| Cigarettes per day | 17.0 number of cigarettes/day STANDARD_DEVIATION 6.9 | 17.0 number of cigarettes/day STANDARD_DEVIATION 6.9 | 0 number of cigarettes/day STANDARD_DEVIATION 0 | 17.0 number of cigarettes/day STANDARD_DEVIATION 6.9 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 3 Participants | 2 Participants | 1 Participants | 6 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 37 Participants | 38 Participants | 42 Participants | 117 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 2 Participants | 2 Participants | 0 Participants | 4 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 17 Participants | 17 Participants | 18 Participants | 52 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 1 Participants | 0 Participants | 2 Participants |
| Race (NIH/OMB) White | 24 Participants | 24 Participants | 25 Participants | 73 Participants |
| Region of Enrollment United States | 42 Participants | 42 Participants | 43 Participants | 127 Participants |
| Sex: Female, Male Female | 15 Participants | 15 Participants | 18 Participants | 48 Participants |
| Sex: Female, Male Male | 27 Participants | 27 Participants | 25 Participants | 79 Participants |
| Years of regular smoking | 22.2 years STANDARD_DEVIATION 12.8 | 22.2 years STANDARD_DEVIATION 12.8 | 0 years STANDARD_DEVIATION 0 | 22.2 years STANDARD_DEVIATION 12.8 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 6 | 0 / 6 |
| other Total, other adverse events | 0 / 6 | 0 / 6 |
| serious Total, serious adverse events | 0 / 6 | 0 / 6 |
Outcome results
Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans
BP provides an estimate of the product of the density of available receptors (Bmax' or the receptor density Bmax less those occupied by endogenous transmitters) and the affinity \[1/equilibrium dissociation constant (KD)\]. We use reference tissue graphical analysis (RTGA) to obtain regional BP values using occipital lobe as a reference region. Negative BP change means means a decrease in the BP and positive BP change means an increase in the BP.
Time frame: 90 minutes
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Nicotine Patch - Transdermal | Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | BP Change - Left Amygdala | -2.47 ratio | Standard Error 3.91 |
| Nicotine Patch - Transdermal | Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | BP Change - Ventral Striatum | -1.24 ratio | Standard Error 3.5 |
| Placebo NRT | Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | BP Change - Left Amygdala | -5.94 ratio | Standard Error 3.91 |
| Placebo NRT | Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | BP Change - Ventral Striatum | -9.25 ratio | Standard Error 3.5 |
| Healthy Non-smoker Comparison | Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | BP Change - Left Amygdala | 5.60 ratio | Standard Error 2.66 |
| Healthy Non-smoker Comparison | Change in Mu-opioid Receptor Binding Potential (BP) Between Baseline and Post-patch Scans | BP Change - Ventral Striatum | 0.59 ratio | Standard Error 2.38 |
Relationship Between Change in Mu-opioid Receptor Binding Potential and Minnesota Nicotine Withdrawal Scale Score
Regression measure (β) between change in mu-opioid receptor binding potential between baseline scan and post-treatment scan and mean Minnesota Nicotine Withdrawal Scale (MNWS) score on Days 2 - 4 of the Clinical Research Unit stay. The MNWS is a self-report measure that consists of 14 nicotine withdrawal symptoms each rated on a 0 - 4 response scale for severity over the past 24 hours. Higher scores are indicative of greater nicotine withdrawal severity.
Time frame: 72 hours
Population: This assessment was not done on the healthy non-smokers because they didn't have any nicotine craving.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Nicotine Patch - Transdermal | Relationship Between Change in Mu-opioid Receptor Binding Potential and Minnesota Nicotine Withdrawal Scale Score | Left Amygdala | -0.087 unitless |
| Nicotine Patch - Transdermal | Relationship Between Change in Mu-opioid Receptor Binding Potential and Minnesota Nicotine Withdrawal Scale Score | Ventral Striatum | 0.419 unitless |
| Placebo NRT | Relationship Between Change in Mu-opioid Receptor Binding Potential and Minnesota Nicotine Withdrawal Scale Score | Left Amygdala | -0.836 unitless |
| Placebo NRT | Relationship Between Change in Mu-opioid Receptor Binding Potential and Minnesota Nicotine Withdrawal Scale Score | Ventral Striatum | -0.794 unitless |
Relationship Between Change in Mu-opioid Receptor Binding Potential and Visual Analog Craving Scale Score
Regression measure (β) between change in mu-opioid receptor binding potential between baseline scan and post-treatment scan in the left amygdala and mean Craving Visual Analog Scale score on Days 2 - 4 of the Clinical Research Unit stay. Craving visual analog scale ranges from 0 (not at all) to 20 (worst ever).
Time frame: 72 hours
Population: This assessment was not done on the healthy non-smokers because they didn't have any nicotine craving.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Nicotine Patch - Transdermal | Relationship Between Change in Mu-opioid Receptor Binding Potential and Visual Analog Craving Scale Score | 0.556 unitless |
| Placebo NRT | Relationship Between Change in Mu-opioid Receptor Binding Potential and Visual Analog Craving Scale Score | -0.550 unitless |