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Biomedical subjects

M L Stitzer

Publications and source records attributed to M L Stitzer.

At least 91 records · Page 5Linked to original sources
PubMed1991

Smoking cessation and weight gain.

Significant progress has been made in the research on smoking cessation and weight gain since the 1988 Surgeon General's Report, particularly on mechanisms and treatment methods. Smoking cessation results in weight gain in most quitters, primarily due to changes in caloric intake and to a lesser extent from changes in energy expenditure. Thus far, pharmacologic treatments appear more efficacious at preventing the weight gain than behavioral methods. And regarding who should receive treatment, preliminary research suggests that females are more concerned about postcessation weight gain than males, and it is the concern about weight gain--more than the weight gain itself--that appears to play an important role in relapse to smoking. Given the progress that has been made along the spectrum from mechanisms to treatment, those concerned about postcessation weight now have treatment options for preventing weight gain in the critical period immediately after smoking cessation. However, continued research into mechanisms, treatment methods, and individual differences will surely result in new and more effectively tailored treatment options.

Combined Modality Therapy↗
PubMed1991

Predictors of opiate drug abuse during a 90-day methadone detoxification.

The behavioral circumstances related to opiate drug use were examined during a 90-day out-patient methadone detoxification. Seventy-one subjects (55 male and 16 female) were followed from the day of intake to treatment termination. Data were collected by means of a weekly structured interview. Questions were asked about each occasion of opiate use in the previous week with respect to time, source, cost, social circumstance, etc. Monitored urine samples were tested x 3/week to verify verbal reports. The study demonstrated beneficial effects of the detoxification treatment by showing dramatic decreases in rates and amounts of opiate drug use during treatment. The study also identified race (p less than .0008; t = -3.522; beta = -0.366), gender (p less than .0243; t = 2.305; beta = 0.222), and the number of opiate use episodes/week at baseline (p less than .0013; t = -3.364; beta = -0.338) as significant and independent predictors of treatment outcome. Current duration of regular and continuous opiate use was also found to be marginally significant. The overall regression was highly significant (p less than .0001; F = 9.176; df = 4,66). A second regression analysis with race, age, and gender excluded as independent variables was conducted in order to derive indices which were related to behavioral and environmental characteristics versus global physical/cultural identification. With race and gender removed, the overall regression was still highly significant, although less than a fifth of the variance was accounted for. The number of opiate use episodes/week at baseline and the total number of drug-related stimulus cue exposures at baseline were found to be independently significant variables in the analysis. Knowledge of the impact of such behavioral factors on the treatment process may enable us to better understand the role of environmental contributors to opiate use. Such information may also help us to direct our limited resources and to better focus our treatment interventions.

Adult↗
PubMed1990

Preference among research cigarettes with varying nicotine yields.

Cigarette smokers (N = 18), primarily women, chose, under double blind conditions, among three research cigarettes with nicotine yields of 0.17, 0.89 and 2.02 mg. Choices were made daily for 12 days following an initial 24-hour forced exposure to each cigarette type. Each subject developed a clear and stable preference for one cigarette type. Of 211 total choice opportunities analyzed, 46% were for the highest nicotine yield cigarette, 29% were for the medium yield, and 25% of the total dose selections were for the low yield cigarettes, suggesting a weak effect of dose. Across subjects, however, the preferences which developed were not significantly related to nicotine yield: low and medium yield cigarette were each preferred by 5 subjects; the remaining 8 subjects came to prefer the high yield cigarette. There was no consistent relationship between nicotine yield of the preferred experimental cigarette and that of the subjects' usual brand. In general, the cigarette choice data are consistent with the behavior of smokers in nonlaboratory settings who also tend to develop stable brand preferences. Specifically, within the range of cigarettes evaluated in this study, nicotine yield is not a strong determinant of cigarette type/brand preference.

Choice Behavior↗
PubMed1990

Acute opioid physical dependence in humans: effect of naloxone at 6 and 24 hours postmorphine.

Previous studies in our laboratory have documented the occurrence of naloxone-precipitated opioid abstinence from 45 minutes to 6 hours after acute morphine administration in humans. This study extended the morphine-naloxone interval to 24 hours and examined the effect of repeated naloxone challenges on withdrawal responses. Six male nondependent opiate users participated in eight experimental sessions in which they received single IM injections of morphine (18 mg/70 kg) followed 6 and 24 hours later by challenge sessions with IM placebo or naloxone (10 mg/70 kg). Naloxone challenge at 6 hours postmorphine reversed morphine-induced miosis and subjective reports of opiate symptoms, drug high, good drug effects, and drug liking. At 24 hours postmorphine, naloxone had no effect on these measures, which had returned to premorphine levels. However, at 6 and 24 hours postmorphine, naloxone precipitated subjective symptoms and observer-rated signs of opioid abstinence. When naloxone challenge at 24 hours was preceded by naloxone at 6 hours postmorphine, the magnitude of abstinence symptoms and signs was attenuated. These data suggest that morphine-induced adaptational changes underlying the development of physical dependence persist beyond other measureable agonist effects, and that these changes are disrupted or reversed by repeated antagonist administration.

Double-Blind Method↗
PubMed1990

The behavioral pharmacology of alcohol and other drugs. Emerging issues.

Alcohol and other drugs are compared with respect to their abuse liability and dependence potential. Drug-reinforced behavior is defined, and factors related to the establishment of this behavior that have received increasing experimental attention in recent years are reviewed. Acquisition techniques, schedule of access, route of self-administration, and organism factors, such as species, gender, and genetic background, are discussed. Other areas of emerging interest are the effect of feeding regimens, alternative reinforcers, and social conditions on drug-reinforced behavior. Also, biochemical factors such as neurochemical alterations, hormonal changes, and alcohol and other drug combinations, are considered. Finally, dependence potential is considered in terms of observational changes and performance alterations that seem to be sensitive indicators of the protracted aspects of drug withdrawal. The relationship between drug-seeking behavior and withdrawal is examined.

Alcohol Drinking↗
PubMed1990

Acute opioid physical dependence in humans: effect of varying the morphine-naloxone interval II.

Previous studies have demonstrated antagonist-precipitated withdrawal from 45 min to 24 hr after acute opioid administration in nondependent human subjects. The purpose of this study was to examine longer postagonist intervals and to determine the maximum interval between agonist administration and antagonist challenge at which precipitated withdrawal can be observed. During this study 6 nondependent male volunteers who reported using opiates an average of 4 times per week received naloxone challenges (10 mg/70 kg i.m.) at 6, 12, 24, 36, 48, 60, or 72 hr after single i.m. injections of morphine (18 mg/70 kg or 30 mg/70 kg). Each interval was tested independently in random order. Naloxone reliably precipitated withdrawal signs and symptoms at 6 and 12 hr postmorphine. Withdrawal symptoms were greatly diminished in intensity at 24-hr postmorphine and were not elicited at postmorphine intervals longer than 24 hr. Withdrawal precipitation persisted somewhat longer than pupillary constriction because pupils had returned to predrug diameters by 24 hr postmorphine but, generally, there appeared to be correspondence between offset of agonist effects and dissipation of precipitated withdrawal. This study extends observations about the time course of acute physical dependence effects which begin within minutes after acute morphine exposure, dissipate within 36 hr, are associated with the onset and offset of agonist effects and do not require chronic opioid administration.

Adult↗
PubMed1989

Effect of d-amphetamine, secobarbital, and marijuana on choice behavior: social versus nonsocial options.

The effects of oral d-amphetamine and secobarbital and smoked marijuana on human social conversation and preference for socializing were studied in three separate experiments. During experimental sessions, active drug or placebo was administered using an acute or divided dosing procedure. Subjects who received drug then engaged in a discrete-trial choice procedure in which they made a series of mutually exclusive choices between a social (talking with their nondrugged partner) and nonsocial (sitting quietly alone) option. Lapel microphones and voice operated relays measured seconds of speech. Subjects engaged in greater amounts of conversation and chose the social option more frequently following acute dosing of d-amphetamine and secobarbital compared with placebo. Acute administration of marijuana did not significantly affect social speech or choice behavior, producing slight decreases in both measures. Acute dosing of all drugs significantly increased subjective drug effect or drug high; however, only secobarbital affected the circular lights task, producing significant performance decrements. The shifts in preference toward the social option observed with d-amphetamine and secobarbital suggest that these drugs increased the reinforcing effects of socializing relative to sitting alone. This may be one mechanism by which psychoactive drugs facilitate social conversation.

Adult↗
PubMed1989

Nicotine replacement: ten-week effects on tobacco withdrawal symptoms.

This study examined the long-term effects of nicotine replacement on tobacco withdrawal symptoms. Smokers (N = 40 community volunteers) maintained biologically validated smoking abstinence under closely monitored conditions while chewing 2 mg nicotine gum (Nicorette; average of 6.9 pieces per day) or placebo gum during the first 10 weeks following smoking cessation. During the first postcessation week symptoms of irritability, anxiety, impatience, restlessness, excessive hunger, difficulty concentrating, drowsiness, sleep disturbance and tobacco craving intensity were significantly lower in active as compared with placebo nicotine gum subjects. Symptoms of psychological distress including irritability, anxiety and impatience declined over time in placebo subjects and were suppressed by replacement therapy below placebo treatment levels only during the first 4-5 weeks after smoking cessation. On other items, most notably increased appetite and excessive eating, stable between-group differences persisted over the entire 10-week trial. The data suggest that use of active gum beyond the first 5 weeks post-cessation may be inconsequential as far as suppression of certain key symptoms of psychological disturbance is concerned, but more prolonged use of active gum would be advisable if the long-term nicotine replacement effects observed (e.g. decreased hunger) are relevant to smoking relapse prevention.

Adolescent↗
PubMed1989

Effects of tetrahydrocannabinol content on marijuana smoking behavior, subjective reports, and performance.

This study investigated the smoking topography of marijuana and its effect on heart rate, subjective reports, and cognitive/psychomotor task performance. Male subjects (N = 12) with histories of moderate marijuana use smoked ad lib one cigarette containing 0, 1.3, or 2.7% delta 9-THC on separate days. Smoking topography measures revealed smaller puff and inhalation volumes and shorter puff duration for the high marijuana dose compared to the low dose. No other smoking behavior differed between the active doses. Heart rate was increased dose dependently over placebo levels. Active marijuana also increased subjective reports of drug effect over placebo, but not dose dependently. Significant memory impairment was observed on a forward and reverse digit span task, and performance was impaired on the digit symbol substitution task by the high, but not low, dose of marijuana. Performance on a divided attention task was not affected by marijuana. Thus, although subjects adjusted their smoking of cigarettes varying in THC content, dose-related effects of marijuana were obtained on several measures. The observed differences and individual variation in smoking topography measures suggest that precise control of smoking behavior would improve the accuracy of marijuana dose delivery.

Adult↗
PubMed1989

Effects of puff number and puff spacing on carbon monoxide exposure from commercial brand cigarettes.

Six chronic smokers of mid- to high-carbon monoxide (CO) yield cigarettes smoked ultralow- (1.6 mg CO), low- (5.9 mg CO) and high- (14.3 mg CO) yield commercial cigarettes under controlled smoking conditions in which either puff number or puff spacing was manipulated. CO exposure (pre- to postsmoking increments) was directly related to the number of puffs taken for all cigarette yields. CO exposure from the high- and low-yield cigarettes was equivalent when the number of puffs taken from the low-yield cigarettes was increased by 50% (from 8 to 12 puffs). In contrast, CO exposure from ultralow-yield cigarettes was still marginally lower than exposure from high-yield cigarettes after a 4-fold increase in puff number (8 to 32 puffs). Puff spacing did not affect biological exposure to CO. The study showed that the number of puffs taken during smoking can clearly affect biological exposure to CO, but that compensation for lowered yield using increased puffs is much more difficult when ultralow- as compared with low or "light"- yield cigarettes are smoked.

Adult↗
PubMed1989

Monologue speech: effects of d-amphetamine, secobarbital and diazepam.

Drugs of abuse from different pharmacological classes increase social conversation. Alcohol and d-amphetamine also increase rates of talking in subjects producing speech monologues in an isolated context. This latter finding suggests that the increases observed during dyadic social conversation may represent general increases in talking and not specific effects on social interaction. The present study was conducted to assess whether other abused drugs also increase monologue speaking. The acute effects of secobarbital (0, 50, 150, 250 mg), d-amphetamine (0, 25 mg) (Experiment 1), and diazepam (0, 10, 20, 40 mg) (Experiment 2) were investigated in healthy, adult volunteers. Secobarbital and d-amphetamine both increased the total amount of speech emitted, while diazepam generally had no effect or decreased talking. Experiment 3 was conducted to further compare the effects of secobarbital (0, 50, 150, 250 mg) and diazepam (0, 5, 15, 25 mg) using a within-subject, crossover design. Secobarbital increased talking in three of the four subjects studied, while diazepam, again, had no effect or decreased talking. In contrast to the differences noted with talking, secobarbital and diazepam both decreased response rates in a nonverbal performance task (i.e., circular-lights procedure); they also produced many similar effects on various subject-rated measures of drug effect. Thus, the differences in the effects of these two compounds on talking are not the result of a general difference in their overall profile of behavioral effects. In summary, the results obtained with secobarbital and d-amphetamine further demonstrate that an explicitly social context is not a necessary condition to observe drug-produced increases in speech quantity. The failure of diazepam to reliably increase talking in the present study illustrates the existence of some pharmacological specificity in the effect of drugs on human speech, and suggests another way in which the behavioral effects of the barbiturates and benzodiazepines may differ.

Administration, Oral↗
PubMed1989

The effects of contingent payment and frequent workplace monitoring on smoking abstinence.

This study examined the relative contribution of contingent payment and worksite CO monitoring to the long-term maintenance of smoking abstinence. Forty-seven hospital employees who had abstained from smoking for five days (confirmed by CO analysis) were randomly assigned to one of three follow-up groups: (a) contingent payment/frequent monitoring (n = 17); (b) noncontingent payment/frequent monitoring (n = 16); or (c) non-contingent payment/infrequent monitoring (n = 14). Contingent payment combined with frequent CO monitoring delayed but did not ultimately prevent subjects relapse to smoking by the end of the six month follow-up. Contingent subjects maintained CO values less than or equal to 11 ppm significantly longer than did either the Non-contingent or the Control subjects (p = .03). CO monitoring alone had no effect on abstinence outcomes; both Noncontingent and Control subjects showed high rates of early relapse.

Adult↗
PubMed1989

Nicotine replacement: effects of postcessation weight gain.

The present study examined nicotine replacement effects on postcessation weight gain in smoking cessation clinic volunteers using objective indices of cigarette smoking, gum use, and body weight. After they achieved abstinence, subjects were randomly assigned to either active nicotine or placebo gum conditions for 10 weeks, during which smoking status was carefully monitored. Analyses revealed strong evidence for a gum effect on weight gain, with active gum users gaining a mean total of 3.8 lb compared with 7.8 lb for placebo gum users at the end of the 10-week trial. Evidence for a dose-response relation was found, suggesting that more gum use (greater than or equal to 6.5 pieces/day) resulted in greater weight suppression. Placebo gum subjects reported greater postcessation increases in eating and hunger compared with active gum subjects. The implications of the weight suppression effect of nicotine gum for smoking cessation treatments are discussed.

Adult↗
PubMed1989

Psychophysiological effects of alcohol-related stimuli: I. The role of stimulus intensity.

The present study extends previous research on conditioning factors in the physiological and subjective responses to naturalistic alcohol-related stimuli. Specifically, the effects of differential alcohol ingestion histories and of stimulus intensity were examined on the occurrence of conditioned responses in the laboratory. Twelve alcoholic subjects and twelve moderate drinkers participated in a single experimental session consisting of randomized presentations of three types of stimulus trials. Each trial included gustatory and visual presentation of alcohol, pepper juice (as a control for stimulus intensity) or water. Both alcohol and pepper juice stimuli significantly increased heart rate and skin conductance responses as compared with water stimuli. In contrast, subjects significantly increased self-report ratings of high and feel different following alcohol stimuli only. Physiological and subjective responses were similar in alcoholics and social drinkers with the exception of significantly higher self-reported craving in alcoholic subjects. These findings suggest that stimulus intensity contributes to the magnitude of physiological but not subjective responses to alcohol-related stimuli.

Adult↗
PubMed1989

Psychophysiological effects of alcohol-related stimuli: II. Enhancement with alcohol availability.

This laboratory study examined methods of enhancing physiological and subjective responses of alcoholics to naturalistic alcohol-related stimuli by repeated exposures to a high-dose alcohol drink. Individual subjects participated in five successive daily sessions consisting of randomized-block presentations of gustatory and visual presentation of alcohol, pepper juice (as a control for stimulus taste intensity), or water stimuli. Following the stimulus trial series, all subjects ingested 1.5 oz of alcohol in a shot glass. Twelve subjects next received a 1.7 g/kg alcohol drink ("high dose alcohol group") on Days 1-4 and placebo on Day 5, and 12 subjects received a placebo drink on all study Days (1-5) ("placebo drink group"). On Day 1, alcohol stimuli generally elicited larger heart rate and skin conductance increases and skin temperature decreases than water or pepper juice stimuli. Alcohol stimuli also elicited greater subjective responses than either pepper juice or water. Alcohol availability within the taste trial markedly increased physiological and subjective reactivity to alcohol-related stimuli, perhaps due to the closer approximation to natural drinking behavior. A comparison with previous data from this laboratory suggests that prestudy deprivation from alcohol, instructions to expect alcohol, a conductive drink setting, and the opportunity to drink alcohol within the session may enhance reactivity to alcohol stimuli in alcoholics.

Adult↗