Impact of differing definitions of dual tobacco use: implications for studying dual use and a call for operational definitions

INTRODUCTION

Concomitant use of two forms of tobacco is an increasing public health concern, yet there is little consensus regarding a consistent definition of so-called "dual use." We defined dual use as cigarette and smokeless tobacco (ST) consumption with either product used daily or nondaily.

METHODS

We analyzed a cohort of 36,013 Air Force recruits. We categorized dual tobacco use across 2 dimensions, type of tobacco products (cigarettes, ST, or others), and the frequency of use (daily vs. nondaily). We determined how varying the definition impacted the prevalence estimates and evaluated the prevalence estimate based on our recommended definition of dual use. Multivariate logistic regression analysis was used to evaluate the risk profile of dual users of ST and cigarettes versus mono users of ST and mono users of cigarettes.

RESULTS

Varying definitions of dual use vary prevalence estimates 50-fold (0.5%-25.3%). Including only ST and cigarettes narrows the prevalence estimate to less than 4-fold (2.0%-9.7%). Dual users are more likely to be young Caucasian males, with lower education, and from families with relatively higher incomes. Compared with mono users, dual users of cigarettes and ST have a distinct pattern of risk profiles.

CONCLUSIONS

Depending on the definition of dual use, markedly different prevalence and risk profiles are observed. Dual users of ST and cigarettes are a unique group of tobacco users. We propose a common definition of dual use to advance our understanding of this unique group.

Tobacco use harm reduction, elimination, and escalation in a large military cohort

OBJECTIVES

We evaluated changing patterns of tobacco use following a period of forced tobacco abstinence in a US military cohort to determine rates of harm elimination (e.g., tobacco cessation), harm reduction (e.g., from smoking to smokeless tobacco use), and harm escalation (e.g., from smoking to dual use or from smokeless tobacco use to smoking or dual use).

METHODS

Participants were 5225 Air Force airmen assigned to the health education control condition in a smoking cessation and prevention trial. Tobacco use was assessed by self-report at baseline and 12 months.

RESULTS

Among 114 baseline smokers initiating smokeless tobacco use after basic military training, most demonstrated harm escalation (87%), which was 5.4 times more likely to occur than was harm reduction (e.g., smoking to smokeless tobacco use). Harm reduction was predicted, in part, by higher family income and belief that switching from cigarettes to smokeless tobacco is beneficial to health. Harm escalation predictors included younger age, alcohol use, longer smoking history, and risk-taking.

CONCLUSIONS

When considering a harm reduction strategy with smokeless tobacco, the tobacco control community should balance anticipated benefits of harm reduction with the risk of harm escalation and the potential for adversely affecting public health.

The Memphis Girls' health Enrichment Multi-site Studies (GEMS): an evaluation of the efficacy of a 2-year obesity prevention program in African American girls

OBJECTIVE

To determine the efficacy of a 2-year obesity prevention program in African American girls.

DESIGN

Memphis GEMS (Girls' health Enrichment Multi-site Studies) was a controlled trial in which girls were randomly assigned to an obesity prevention program or alternative intervention.

SETTING

Local community centers and YWCAs (Young Women's Christian Associations) in Memphis, Tennessee.

PARTICIPANTS

Girls aged 8 to 10 years (N = 303) who were identified by a parent or guardian as African American and who had a body mass index (BMI) at or higher than the 25th percentile for age or 1 parent with a BMI of 25 or higher.

INTERVENTIONS

Group behavioral counseling to promote healthy eating and increased physical activity (obesity prevention program) or self-esteem and social efficacy (alternative intervention).

MAIN OUTCOME MEASURE

The BMI at 2 years.

RESULTS

The BMI increased in all girls with no treatment effect (obesity prevention minus alternative intervention) at 2 years (mean, 0.09; 95% confidence interval [CI], -0.40 to 0.58). Two-year treatment effects in the expected direction were observed for servings per day of sweetened beverages (mean, -0.19; 95% CI, -0.39 to 0.09), water (mean, 0.21; 95% CI, 0.03 to 0.40), and vegetables (mean, 0.15; 95% CI,-0.02 to 0.30), but there were no effects on physical activity. Post hoc analyses suggested a treatment effect in younger girls (P for interaction = .08). The mean BMI difference at 2 years was -2.41 (95% CI, -4.83 to 0.02) in girls initially aged 8 years and -1.02 (95% CI, -2.31 to 0.27) in those initially aged 10 years.

CONCLUSIONS

The lack of significant BMI change at 2 years indicates that this intervention alone is insufficient for obesity prevention. Effectiveness may require more explicit behavior change goals and a stronger physical activity component as well as supportive changes in environmental contexts.

Differences between intermittent and light daily smokers in a population of U.S. military recruits

INTRODUCTION

Few studies have assessed differences between intermittent and light smokers, particularly among young adults. Exploring these differences promotes a systematic approach to research and treatment in low-level smokers. This study explored demographic, tobacco-related, and psychosocial predictors of intermittent nondaily smoking relative to light smoking among basic military training (BMT) recruits. The impact of smoking status on abstinence rates at follow-up was also assessed.

METHODS

Participants were 5,603 U.S. Air Force BMT intermittent nondaily (n = 3,134) or light daily (n = 2,469) smoking recruits participating in a population-based group randomized trial targeting tobacco use prevention and cessation (Klesges et al., 2006, Efficacy of a tailored tobacco control program on long-term use in a population of U.S. military troops. Journal of Consulting and Clinical Psychology, 74, 295-306.). Participants completed baseline measures assessing demographics; tobacco use and history; and common social, attitudinal, and behavioral risk factors for tobacco use. Flights of recruits were randomly assigned to a tobacco use intervention or health education control intervention. At the 1-year follow-up, participants reported 7-day point prevalence and continuous abstinence.

RESULTS

Intermittent nondaily smoking relative to light daily smoking was associated with lesser perceived addiction, intermittent and daily use of smokeless tobacco, nonsmoking male and female heads of household, lesser likelihood of smoking while stressed or while bored, and higher likelihood of intentions to quit smoking. Intermittent smokers were significantly more likely than light daily smokers to report abstinence at follow-up.

DISCUSSION

Intermittent and daily light smokers differ on several tobacco-related and psychosocial variables. Attending to these factors in prevention and cessation programs may enhance abstinence in both groups.

Measurement of body composition in 8-10-year-old African-American girls: a comparison of dual-energy X-ray absorptiometry and foot-to-foot bioimpedance methods

OBJECTIVE

The purpose of this study was to evaluate body composition outcomes of foot-to-foot (FF) bioelectrical impedance (BIA) and dual-energy x-ray (DEXA) in 8 to 10-year-old African-American girls and, if different, to develop and cross-validate specific BIA prediction equations for this at-risk group.

METHODS

DEXA and FF-BIA body composition outcomes were analyzed in 183, 8-10-year-old African-American girls from the Memphis site of the Girls health Enrichment Multi-site Study (GEMS).

RESULTS

Mean body composition outcomes by FF-BIA and DEXA were significantly different (p<0.0001); therefore, population-specific equations were developed and cross-validated using split-sample, cross-validation methods. When equations were used, BIA and DEXA outcomes were significantly correlated (percent body fat [r=0.931], fat mass [r=0.985], and fat-free mass [r=0.944]). Mean predicted BIA measurements for body fat, fat mass, and fat-free mass were essentially equal to their counterpart DEXA measurements (t[182]=- 0.013, p = 0.897, t[182]=- 0.06, p=0.956, and t[182]=- 0.26, p=0.792, respectively). The Bland-Altman analysis revealed a significant slope for percent fat (p=0.009) and slopes approaching significance for fat mass (p=0.07) and fat-free mass (p=0.06).

CONCLUSION

Although FF-BIA and DEXA are not directly interchangeable in young African-American girls, these equations accurately estimated average percent fat, fat mass, and fat-free mass of the cross-validation sample of African-American girls. However, the application of this equation may result in potential underestimation or overestimation of fat with respect to DEXA measures in some populations.

Trial design: The St. Jude Children's Research Hospital Cancer Survivors Tobacco Quit Line study

Nearly, one-fifth of childhood cancer survivors (CCSs) smoke cigarettes. Because CCSs are already at greater medical smoking-related risks, targeting them for smoking cessation efforts is a high priority. One of the major challenges with smoking cessation in CCSs is how to reach such a geographically dispersed population. This study aims to demonstrate that these challenges can be overcome through the use of telephone-based tobacco quit lines (QLs). This report describes the design of the St. Jude Cancer Survivor Tobacco QL study, which is a randomized controlled clinical trial that will examine the long-term (1-year) efficacy of a counselor initiated vs. participant initiated tobacco QL with adjunctive nicotine replacement therapy (NRT) in both groups. Participants (N=950) will be recruited nationally and randomly assigned to one of the two interventions. The counselor initiated intervention includes six scheduled telephone sessions of a behavioral intervention and provision of 8 weeks of NRT. The participant initiated intervention allows the participant to call the QL at their convenience, but includes the same six telephone sessions and provision of 2 weeks of NRT. Both groups will receive two follow-up phone calls at 8 weeks and 1 year after enrollment to assess their smoking status. The primary outcome measure is cotinine-validated self-reported smoking abstinence at 1-year follow-up. Results from this study will provide the first evidence about the efficacy of intensive QL cessation intervention in this high-risk population. Such evidence can lead as well to the dissemination of this intervention to other medically compromised populations.

Do we believe the tobacco industry lied to us? Association with smoking behavior in a military population

Despite the dangers of smoking, tobacco companies continue to impede tobacco control efforts through deceptive marketing practices. Media campaigns that expose these practices have been effective in advancing anti-industry attitudes and reducing smoking initiation among young people, yet the association between knowledge of industry practices and smoking cessation and relapse has not been studied. In a large military sample entering Air Force Basic Military Training (BMT), where tobacco use is prohibited, we investigated (i) the prevalence of agreement with a statement that tobacco companies have misled the public about the health consequences of smoking and (ii) the association of this acknowledgement with smoking status upon entry into BMT (N = 36 013). At baseline, 56.6% agreed that tobacco companies have been deceptive, and agreement was a strong predictor of smoking status [smokers less likely to agree, odds ratio (OR) = 0.39, P < 0.01]. At 12-month follow-up, we examined the association between industry perception at baseline and current smoking status (N = 20 672). Recruits who had been smoking upon entry into BMT and who had acknowledged industry deception were less likely to report current smoking (OR = 0.84, P = 0.01). These findings suggest that anti-industry attitudes may affect smoking relapse following cessation.

Measurement characteristics of dietary psychosocial scales in a Weight Gain Prevention Study with 8- to 10-year-old African-American girls

Few measurement instruments for children's eating behaviors and beliefs have been specifically validated for African-American children. Validation within this population is important because of potential cultural and ethnic influences. Objectives were to evaluate established and newly developed or adapted dietary psychosocial measures in a sample of 303 preadolescent African-American girls and their caregivers. Acceptable internal consistency (Cronbach's alpha > or = 0.70) was found for measures of girls' self-efficacy for healthy eating, outcome expectancies for healthy eating, positive family support for healthy eating and household availability of low-fat food and fruit, juice and vegetables (FJV). Evidence for concurrent validity was found with significant associations between self-efficacy for healthy eating and lower intake of energy (r = -0.17) and fat grams (r = -0.16). Greater FJV availability was associated with greater FJV intake (r = 0.14) and lower body mass index (BMI) in girls (r = -0.12). Positive family support for healthy eating was associated with higher BMI in girls (r = 0.41). These results contribute to the development of scales to evaluate prevention interventions related to dietary intake in African-American children.

Relationship between smoking status and body weight in a military population of young adults

The purpose of the present study was to determine the association between smoking and body weight in a cohort of young U.S. Air Force recruits (mean age=20 years) enrolled in basic military training (N=35986). Twenty-two percent of recruits smoked daily prior to basic military training (n=8087) and were compared to never smokers, former smokers, and experimental or nondaily smokers. A three-way interaction among smoking status, gender and ethnicity suggested a small effect for daily smoking among White male recruits only and no significant differences for female recruits or members of any other ethnic group. Although there was a statistically significant relationship between smoking and body weight in White males, the effect size was approximately 1 kg. These results suggest that the energy balance differences in body weight between young smokers and nonsmokers are minimal and that it would take decades to accrue the differences typically seen in adult smokers.

Prevalence and characteristics of energy underreporting in African-American girls

OBJECTIVE

To determine the frequency and characteristics of energy intake underreporting in African-American preadolescent girls as part of the Girls health Enrichment Multi-site Studies (GEMS).

METHODS AND PROCEDURES

Energy intake was summarized using the Nutrition Data System for Research software and computed as a 3-day average of 24-h dietary recalls. Physical activity was assessed by an accelerometer, basal metabolic rate (BMR) was estimated using the World Health Organization's prediction equation, and underreporting of caloric intake was based on the Goldberg equation.

RESULTS

Using a conservative criterion for determining energy underreporting, we classified 54.8% of the girls as underreporters; 45.2% were classified as plausible reporters. Factors related to underreporting included higher BMI (beta = -0.506, P < or = 0.001), older age (beta = -0.159, P = 0.001), greater unhealthy eating behaviors (beta = -0.118, P = 0.025), and higher self-efficacy for diet (beta = -0.098, P = 0.033).

DISCUSSION

Underreporting of dietary intake, specifically energy, is common in African-American preadolescent girls and can be partially explained by weight status and psychosocial variables. The extent of dietary underreporting in specific and high-risk populations is largely unknown and could be evaluated by routinely including a report of such an index in future research studies.

Demographics and Risky Lifestyle Behaviors Associated with Willingness to Risk Sexually Transmitted Infection in Air Force Recruits

Purpose.

To investigate sexually transmitted infection (STL) risk-taking behaviors relative to other lifestyle and risk-taking behaviors.

Design.

The study design is cross sectional.

Setting.

Lackland Air Force Base in San Antonio, Texas.

Subjects.

Participants (N = 32,144) were 100% of Air Force recruits beginning basic military training from August 1995 to August 1996.

Measures.

Recruits completed a questionnaire that included rating the statement “Sex without condoms is sometimes worth the risk of possibly getting AIDS or sexually transmitted diseases.” Risky behaviors, such as risk taking rebelliousness, seat belt use, smoking alcohol use and binge drinking opinions of illicit drug use, and lifestyle behaviors, such as dietary intake and physical activity, were also assessed.

Analysis.

Univariate and multivariate logistic regression analyses examined the relationships between participant characteristics and willingness to risk STI.

Results.

Sixteen percent stated willingness to risk STI to have sex without a condom. Women and white/non-Hispanic participants were less likely to agree with the statement than men and minority participants. Those who reported willingness toward risky sexual behaviors were less likely to use seat belts, were more likely to binge drink, had more positive views of illicit drugs, and reported eating fewer fruits and vegetables.

Conclusion.

Results of this study suggest the importance of continued education on condom use and the possibility that multiple risk behavior interventions include sexual risk components.

Memphis Girls health Enrichment Multi-site Studies (GEMS)

Obesity prevalence is increasing in the U.S., especially among children and minority populations. This report describes the design and baseline data of the ongoing Girls health Enrichment Multi-site Studies (GEMS) trial (Memphis site), which is testing the efficacy of a 2-year family-based intervention to reduce excessive increase in body mass index (BMI). This randomized, controlled trial conducted at community centers in Memphis, Tennessee requires major measurements at baseline and at 12 and 24 months post-randomization. The participants are healthy African-American girls and one parent/caregiver of each girl. Participating girls are of ages 8-10 years, with BMI>or=25th percentile of the CDC 2000 growth charts or with one overweight or obese parent/caregiver (BMI>or=25 kg/m(2)). The active intervention is designed to prevent excessive weight gain by promoting healthy eating habits and increasing physical activity. An alternative intervention (comparison group) promotes general self-esteem and social efficacy. The main outcome measure is the difference between the two treatment groups in the change in BMI at 2 years. Three hundred and three girls have been randomly assigned to receive the test intervention (n=153) or the alternative intervention (n=150). The two groups do not differ in baseline characteristics. At the time of enrollment, the mean age was 9 years, the mean BMI was 22 kg/m(2) (mean BMI percentile=77 th), and 41% were overweight (BMI>/=95th percentile using CDC 2000 growth charts). Participants' intake of fruits and vegetables (1.3 serving/day) and fats (36% kcal), and their participation in moderate-to-vigorous physical activity (20 min/day), did not meet national recommendations. The GEMS obesity prevention intervention targets improved diet and increased physical activity to reduce excessive weight gain in healthy African-American girls of ages 8-10.

The relationship between caffeine and blood pressure in preadolescent African American girls

BACKGROUND

While high caffeine consumption has been shown to be associated with increased blood pressure in controlled experiments, the relationship between caffeine consumption and blood pressure in preadolescent (ages 6-11 years) and adolescent (ages 12-19 years) children has not been well studied. The primary objective of this study was to assess the cross-sectional relationship between caffeine intake and blood pressure in 8- to 10-year-old African American girls who eat an unrestricted diet.

METHODS

Demographic, 24-hour dietary recall, and blood pressure data collected at baseline from 303 African American girls aged 8-10 years in the Girls health Enrichment Multisite Studies (GEMS) cohort were analyzed by using linear and multiple regression models.

RESULTS

Dietary caffeine intake was not associated with either systolic or diastolic blood pressure (P=.33 and P=.36, respectively). However, consistent with the literature, height and body mass index were each positively and independently associated with systolic blood pressure (both P<.0001). Height and amount of sodium intake were positively associated with diastolic blood pressure (P=.01 and P=.02, respectively).

CONCLUSIONS

Dietary caffeine intake in low amounts is not associated with elevated blood pressure in 8- to 10-year-old African American girls who eat an unrestricted diet.

Prevalence of alternative forms of tobacco use in a population of young adult military recruits

Recent evidence suggests that the popularity of certain alternative forms of tobacco may be increasing in adolescents. Little is known, however, about the use of these products among young adults. This study examined the use of alternative tobacco products including bidis, cigars, kreteks (clove cigarettes), pipes, and smokeless tobacco in a large sample of young adult military recruits (N=31107). Overall, 18.5% of participants were using some form of alternative tobacco product prior to entry into Basic Military Training. Results revealed a relatively high prevalence of cigar (12.3%) and smokeless tobacco use (6.7%). Use of other products was less common, including 1.1% for pipes, 2.0% for bidis, and 3.0% for kreteks. With the exception of kreteks, which did not differ by gender, the prevalence of use of alternative tobacco products was greater for males than for females (p<.001). Patterns of use also differed according to other demographic characteristics including race, ethnicity, age, and income. Implications for surveillance and tobacco control efforts are discussed.

Trial design: blood pressure control and weight gain prevention in prehypertensive and hypertensive smokers: the treatment and prevention study

BACKGROUND

Cigarette smokers with elevated blood pressure (BP) are at substantially higher risk for cardiovascular events compared to normotensive smokers. Although smoking cessation should be a primary treatment goal for these patients, increases in body weight accompanying smoking abstinence may further increase BP. Intervention strategies that facilitate smoking cessation and modify adverse changes in body weight and BP are needed.

METHODS

We describe an ongoing multi-site, two-phase, five-year randomized clinical trial. Participants are cigarette smokers with Prehypertension or Stage I Hypertension. In the first phase, participants receive a smoking cessation intervention combining behavioral counseling and nicotine replacement in an open-label fashion. In the second phase, participants who successfully quit smoking are randomly assigned to one of three lifestyle interventions: 1) weight gain prevention, 2) blood pressure control, or 3) usual lifestyle. Participants are followed for one year to assess changes in blood pressure, body weight, dietary intake, and physical activity.

CONCLUSIONS

Results from the proposed study will provide important insights into the efficacy of various approaches to lifestyle modification in smokers at increased risk for cardiovascular events.

Cigarette use among two cohorts of U.S. Air Force recruits, compared with secular trends

This study provides a comparison of cigarette smoking among two cohorts of U.S. Air Force recruits. The first cohort, Air Force 1, entered the military between August 1995 and August 1996. The second cohort, Air Force 2, entered between October 1999 and September 2000. Cigarette use significantly increased among both men (7.0-percentage point increase) and women (7.3-percentage point increase) between the two cohorts. This difference remained statistically significant in models adjusted for demographic differences between the two groups of recruits. Direct standardization methods were then used to compare rates in both Air Force surveys with rates of current smoking reported for a national sample from the Behavioral Risk Factor Surveillance System surveys from the same years. Although the average number of cigarettes smoked and years of smoking decreased between the two cohorts, troops from Air Force 2 reported being less motivated to quit. This study suggests that efforts to reduce smoking among junior enlisted troops in the Air Force should be bolstered.

Characteristics of Air Force personnel who choose pharmacological aids for smoking cessation following an involuntary tobacco ban and tobacco control program

OBJECTIVE

The objective of this study was to compare characteristics of smokers who did and did not report use of cessation aids as part of a tobacco control program in a military setting (n = 8994).

DESIGN

The study is a longitudinal epidemiological study where the relationship between smoking status at follow-up and use of pharmacologic aids to quit smoking were assessed.

MAIN OUTCOME MEASURES

Smoking cessation, post baseline use of cessation aids to quit smoking.

RESULTS AND CONCLUSIONS

Individuals remaining abstinent were 70% less likely to have used NRT/pharmacological aids compared to those that relapsed. NRT/pharmacological aid users were more likely to report plans to smoke after military training, to have friends who smoke, and to accept a cigarette from a friend. NRT/pharmacological aid users were more likely to believe that using NRT was safer than smoking and to have engaged in harm reduction strategies. Our findings suggest that selection bias related to such characteristics may explain some of the discrepancies between effect sizes reported in efficacy compared to effectiveness studies of NRT and smoking outcomes currently reported in the literature.

The validity of self-rated health as a measure of health status among young military personnel: evidence from a cross-sectional survey

Background

Single item questions about self ratings of overall health status are widely used in both military and civilian surveys. Limited information is available to date that examines what relationships exist between self-rated health, health status and health related behaviors among relatively young, healthy individuals.

Methods

The current study uses the population of active duty United States Air Force recruits (N = 31,108). Participants completed surveys that asked about health behaviors and health states and were rated their health on a continuum from poor to excellent.

Results

Ratings of health were consistently lower for those who used tobacco (F = 241.7, p < .001), reported binge drinking (F = 69.0, p < .001), reported drinking and driving (F = 19.4, p < .001), reported taking health risks (F = 109.4, p < .001), were depressed (F = 256.1, p < .001) and were overweight (F = 39.5, p < .001).

Conclusion

Given the consistent relationship between self-rated overall health and factors important to military health and fitness, self-rated health appears to be a valid measure of health status among young military troops.

Waterpipe smoking among American military recruits

BACKGROUND

Waterpipe smoking, a traditional Middle Eastern tobacco use method, has increased dramatically among Arab adolescents and young adults. Anecdotal evidence also suggests that usage is on the rise among young people in the U.S., but epidemiological data are lacking.

METHODS

From self-report health surveys collected during 1999-2002, we examined the prevalence and predictors of waterpipe use among U.S. Air Force recruits (n = 20,673; mean age = 20.0 years; range = 17-35).

RESULTS

Waterpipe use was reported by 0.3% (n = 59) of recruits and was unrelated to age, gender, ethnicity, or family income. Compared to non-users, waterpipe users were more likely to plan to smoke cigarettes in the coming year (P value < 0.05) and to believe that switching from cigarettes to other tobacco products reduces smoking-related health risks (P values < 0.002). Multivariate (logistic regression) analyses revealed several factors that distinguished waterpipe users from non-users, including higher education level (odds ratio [OR] = 1.94), having experimented with cigarettes before Basic Military Training (BMT; OR = 1.99), and using cigarettes (OR = 2.17) and other tobacco products (OR = 13.81) at the time of entry into BMT. Compared to recruits who used cigarettes only, waterpipe smokers were more educated (OR = 1.83), more likely to have engaged in experimental (OR = 3.30) or regular (OR = 3.87) use of tobacco products other than cigarettes prior to BMT, and less likely to have been a current (OR = 0.10) or former (OR = 0.11) smoker at the time of entry into BMT.

CONCLUSION

Despite concerns that waterpipe smoking is increasing among young people in the U.S., use was low among military recruits.