Behavioral mediators of treatment effects in the weight loss maintenance trial.

BACKGROUND: The Weight Loss Maintenance Trial tested strategies for maintenance of weight loss. Personal contact was superior to interactive technology and self-directed conditions. PURPOSE: We aimed to identify behavioral mediators of the superior effect of personal contact vs. interactive technology and of personal contact vs. self-directed arms. METHODS: Overweight/obese adults at risk for cardiovascular disease (n = 1,032) who lost at least 4 kg were randomized to personal contact, interactive technology, or self-directed. After 30 months, 880 participants had data on weight and behavioral strategies. RESULTS: Reported increase of intake of fruits and vegetables and physical activity and more frequent self-weighing met criteria as mediators of the better outcome of personal contact vs. interactive technology. Increased intake of fruits and vegetables, more frequent self-weighing, and decreased dessert consumption were mediators of the difference between personal contact vs. self-directed. CONCLUSION: Inducing changes in the identified behaviors might yield better outcomes in future weight loss maintenance trials.

Branched-chain amino acid levels are associated with improvement in insulin resistance with weight loss.

AIMS/HYPOTHESIS: Insulin resistance (IR) improves with weight loss, but this response is heterogeneous. We hypothesised that metabolomic profiling would identify biomarkers predicting changes in IR with weight loss. METHODS: Targeted mass spectrometry-based profiling of 60 metabolites, plus biochemical assays of NEFA, ß-hydroxybutyrate, ketones, insulin and glucose were performed in baseline and 6 month plasma samples from 500 participants who had lost ≥4 kg during Phase I of the Weight Loss Maintenance (WLM) trial. Homeostatic model assessment of insulin resistance (HOMA-IR) and change in HOMA-IR with weight loss (∆HOMA-IR) were calculated. Principal components analysis (PCA) and mixed models adjusted for race, sex, baseline weight, and amount of weight loss were used; findings were validated in an independent cohort of patients (n = 22). RESULTS: Mean weight loss was 8.67 ± 4.28 kg; mean ∆HOMA-IR was -0.80 ± 1.73, range -28.9 to 4.82). Baseline PCA-derived factor 3 (branched chain amino acids [BCAAs] and associated catabolites) correlated with baseline HOMA-IR (r = 0.50, p < 0.0001) and independently associated with ∆HOMA-IR (p < 0.0001). ∆HOMA-IR increased in a linear fashion with increasing baseline factor 3 quartiles. Amount of weight loss was only modestly correlated with ∆HOMA-IR (r = 0.24). These findings were validated in the independent cohort, with a factor composed of BCAAs and related metabolites predicting ∆HOMA-IR (p = 0.007). CONCLUSIONS/INTERPRETATION: A cluster of metabolites comprising BCAAs and related analytes predicts improvement in HOMA-IR independent of the amount of weight lost. These results may help identify individuals most likely to benefit from moderate weight loss and elucidate novel mechanisms of IR in obesity.

Recruitment for phase II of the Trials of Hypertension Prevention. Effective strategies and predictors of randomization. Trials of Hypertension Prevention (TOHP) Collaborative Research Group.

Phase II of the Trials of Hypertension Prevention is a multicenter, randomized, controlled trial designed to determine the efficacy of weight loss and reduction of sodium intake for lowering blood pressure and incidence of hypertension among persons with high-normal levels of blood pressure. The 2 x 2 factorial study design includes weight loss alone, restricted sodium intake alone, the combination of weight loss and sodium restriction, and a control group. Nine clinical centers used a variety of recruitment strategies to enroll 2382 participants over 17 months, which exceeded the sample size goal of 2250. Among randomized participants, 21% were minorities and 34% were women. Overall, direct mail generated the most randomized participants (73%), followed by community screening (12%) and media advertisement (11%). Referrals from community health care providers yielded few participants. Prescreening improved overall efficiency and reduced costs. Participants who were more likely to drop out voluntarily during the three-visit screening regimen tended to be younger, single, male, smokers, and less educated.

Design of a multicenter trial to evaluate long-term life-style intervention in adults with high-normal blood pressure levels. Trials of Hypertension Prevention (phase II). Trials of Hypertension Prevention (TOHP) Collaborative Research Group.

Phase II of the Trials of Hypertension Prevention (TOHP) is a multicenter, randomized trial sponsored by the National Heart, Lung, and Blood Institute designed to test whether weight loss alone, sodium reduction alone, or the combination of weight loss and sodium reduction will decrease diastolic (DBP) and systolic blood pressure (SBP) as well as the incidence of hypertension (DBP > or = 90 mm Hg, SBP > or = 140 mm Hg, and/or use of antihypertensive medications) in subjects with high-normal DBP (83 to 89 mm Hg) and SBP less than 140 mm Hg at entry. These interventions were chosen for longer-term testing with end points including hypertension prevention as well as blood pressure (BP) change based on their demonstrated short-term efficacy in reducing BP in phase I of TOHP. The phase II study population is comprised of 2382 participants (1566 men and 816 women) who are 110 to 165% of desirable body weight, allocated at random to the four treatment arms using a 2 x 2 factorial design. The trial has 80% power to detect an overall treatment effect on DBP of 1.2 mm Hg for weight loss or sodium reduction and a difference of 1.6 mm Hg between the combined intervention and placebo groups. BP observers are blinded to participant treatment assignments. Participants will be followed for 3 to 4 years. This trial may have important public policy implications concerning the ability of life-style modifications to reduce BP and prevent the development of hypertension over the long term, thereby avoiding the need for drug therapy which while effective is costly and may have side effects.

Stress management intervention for primary prevention of hypertension: detailed results from Phase I of Trials of Hypertension Prevention (TOHP-I).

PURPOSE: Stress Management Intervention (SMI) was one of seven nonpharmacologic approaches evaluated in Phase I Trials of Hypertension Prevention (TOHP-I) for efficacy in lowering diastolic blood pressure (BP) in healthy men and women aged 30 to 54 years with diastolic BP 80-89 mm Hg. METHODS: A total of 242 and 320 participants were randomized to SMI or an "assessment only" SMI Control, respectively, at four clinical centers. The SMI consisted of 37 contact hours in 21 group and two individual meetings over 18 months and included: training in four relaxation methods, techniques to reduce stress reactions, cognitive approaches, communication skills, time management, and anger management within a general problem-solving format. Standardized protocols detailed methods and timing for collecting BP, psychosocial measures, and urinary samples from both SMI and SMI Control participants. RESULTS: In intention-to-treat analyses, although significant baseline to termination BP reductions were observed in both groups, net differences between the SMI and SMI Control groups' BP changes (mean (95% CI)) were not significant: -0.82 (-1.86, 0.22) for diastolic BP, and -0.47 (-1.96, 1.01) for systolic BP. Extensive adherence sub-group analyses found one effect: a significant 1.36 mm Hg (p = 0.01) reduction in diastolic BP relative to SMI Controls at the end of the trial for SMI participants who completed 61% or more of intervention sessions. CONCLUSIONS: While the TOHP-I SMI was acceptable to participants as evident from high levels of session completion, the absence of demonstrated BP lowering efficacy in intention-to-treat analyses suggests that the TOHP-I SMI is an unlikely candidate for primary prevention of hypertension in a general population sample similar to study participants. The isolated finding of significant diastolic BP lowering in SMI participants with higher adherence provides very weak evidence of SMI BP lowering efficacy and may be a chance finding. Whether similar or other stress management interventions can produce significant BP lowering in populations selected for higher levels of BP, stress, or intervention adherence remains to be demonstrated.

Social networks as predictors of ischemic heart disease, cancer, stroke and hypertension: incidence, survival and mortality.

Three social network measures were obtained from a randomly sampled cohort of 2603 HMO members in 1970-71. Mortality and first incidence of ischemic heart disease, cancer, stroke, and hypertension were assessed over the next 15 years. Outcome data were adjusted for age, sex, smoking, SES, and baseline health status. Persons with histories of a given morbidity at or prior to baseline were excluded from the analyses of that morbidity. Social network measures, particularly network scope (a measure of the number of different domains in which a person has social contacts), were powerful predictors of 15-year mortality hazard, but weak predictors of incident disease. Only network scope predicted IHD incidence, and none of the other morbidities was predicted by the social network measures. However, social network measures were strong predictors of both cause-specific and all-cause mortality among persons who had incident cases of IHD, cancer, and stroke. These data suggest that social networks may be more effective in supporting recovery after illness has occurred than in preventing the incidence of new disease.

Does gender affect response to a brief clinic-based smoking intervention?

INTRODUCTION: Although recent reviews suggest few gender differences in smoking-cessation outcomes, it is important to establish whether gender differences exist in response to the brief interventions increasingly recommended as part of routine medical care. METHODS: We used data from an efficacious primary care-based smoking intervention to examine gender differences in smoking characteristics, use of intervention components, self-reported quitting activities, and cessation outcomes among all smokers randomized to receive clinician advice and nurse-assisted intervention (n = 1,978, 58% female). RESULTS: Although female and male smokers differed on a number of sociodemographic and smoking-related characteristics, they were equally likely to participate in each step of the recommended intervention. Female and male smokers were also equally likely to report quit attempts and cessation at 3, 12, and 3 and 12 months (combined long-term cessation endpoint). Similarly, no gender difference in relapse at 12 months was seen. Women attempting to quit used a greater number and variety of smoking-cessation strategies, suggesting that, although outcomes were similar, the processes of cessation may vary by gender. CONCLUSIONS: Since this brief intervention in primary care was equally efficacious and acceptable to female and male smokers, broader implementation in medical settings of this population-based approach to reducing tobacco use is warranted. Indeed, widespread implementation of smoking-cessation programs in medical settings may particularly benefit women, who are more likely than men to have contacts with the medical care system.

Brief intervention in a primary care setting for hazardous drinkers.

INTRODUCTION: The study was designed to test a brief intervention for reducing alcohol consumption among moderate to heavy (hazardous) drinkers in a busy HMO primary care setting. METHODS: In a randomized controlled trial, hazardous drinkers (n = 516) were identified by the AUDIT screening questionnaire. Intervention included brief clinician advice (30 seconds), a 15-minute motivational session by counselors, and printed materials. RESULTS: At six-month follow-up, intervention subjects reported fewer total standard drinks in the past three months (176 versus 216, P = .04, one-tailed) and fewer drinking days per week (2.8 versus 3.3, P = .02) than controls, but similar drinks per drinking day (3.3 versus 3.5; P = .13). At 12 months, intervention subjects again reported fewer drinking days per week (2.7 versus 3.1; P = .04) than controls, but similar numbers of standard drinks (157 versus 179; P = .13) and drinks per drinking day (3.6 versus 3.3; P = .20). Intervention subjects were somewhat more likely than controls to report drinking within daily recommended limits (< or = 3 for men, < or = 2 for women) at both six months (79% versus 71%; P = .06) and 12 months (80% versus 73%; P = .07), but did not differ significantly from controls on other drinking outcomes (percent abstinent, frequency of drinking > or = 6 drinks per drinking occasion, estimated peak blood alcohol concentration), or use of medical care in the year following intervention. CONCLUSIONS: A one-time, brief motivational intervention using minimal clinician time supplemented by trained counselors resulted in a modest reduction in frequency of alcohol consumption in a busy primary care population. Future research should focus on strengthening and maintaining intervention effects.

The Nutrition Attitude Survey: associations with dietary habits, psychological and physical well-being, and coronary risk factors.

Attitudes play an important role in the adoption and maintenance of a variety of health habits. In the present study, the Nutrition Attitude Survey (NAS) was developed to measure attitudes pertaining to the adoption of a low-fat, low-cholesterol diet. Factor analysis identified four primary attitudinal factors: Helpless and Unhealthy, Food Exploration, Meat Preference, and Health Consciousness. For a community sample of 415 healthy men and women, relationships were examined among these attitudinal factors and dietary habits, family food patterns, medical and psychological symptoms, and traditional coronary risk factors. For both men and women, the Helpless and Unhealthy factor was associated with increased meat consumption, weight, emotional distress, reported medical and psychological symptoms, total cholesterol, and low-density lipoprotein cholesterol. The Food Exploration factor was more characteristic of younger men and women and positively associated with men's reported involvement in family food preparation activities. For both sexes, Meat Preference scores were positively associated with meat consumption and inversely associated with consumption of meatless meals, beans, and fruit. Health Consciousness factor scores were associated with less meat consumption, more meatless meals, and better overall dietary adherence scores for both men and women. Overall, the findings provide initial support for the reliability and predictive validity of the NAS and underscore the importance of assessing and addressing the attitudes and preferences of participants in dietary intervention programs.

Type A behavior, attentional style, and symptom reporting among adult men and women.

Type A behavior and its components (measured on the JAS) were examined in relation to attentional style and symptom reporting in 294 healthy adult men and women. The results showed that for both men and women the JAS Type A, Job Involvement, and Hard Driving factors were all associated with self-reported attentional effectiveness as measured by the Nideffer Test of Attentional and Interpersonal Style. However, a fourth JAS factor, Speed and Impatience, was associated with Nideffer measures of cognitive overload. For both men and women, the Type A, Speed and Impatience, and Hard Driving factors were all positively associated with the number of medical and psychological symptoms reported on the Cornell Medical Index. In addition, acute psychological distress (Hopkins SCL-90R) was associated with Type A behavior for men and with Speed and Impatience for both sexes. Attention differences did not account for the observed positive relationships between Type A factors and symptom reporting with one exception; attentional overload (internal) appeared to partially explain the relationships between symptom reporting and Speed and Impatience in women. In summary, Type As described themselves as having a broader attentional focus and reported more naturally occurring physical and psychological symptoms than did Type Bs.

Preventing smoking relapse, using an individually tailored skills-training technique.

The effectiveness of a relapse prevention program was studied in a population of 744 smokers. Subjects first attended an intensive 4-day series of 2-hr meetings in which they were trained to use more than 40 behavioral and cognitive smoking cessation techniques. At the 1-week follow-up session, those abstinent from smoking (79%, carbon monoxide verified) were randomly assigned to one of three follow-up conditions: (a) a three-session skills-training program in which subjects developed and actively rehearsed individually tailored coping strategies for likely relapse situations, (b) a three-session discussion control condition in which subjects discussed maintenance but did not develop or rehearse coping strategies, or (c) a no-treatment control condition. Survival analysis indicated higher abstinence rates for the skills-training group than for the control groups throughout the following year. After 12 months, the biochemically confirmed continuous abstinence rate was higher in the skills-training group (41.3%) than in the discussion and no-treatment groups (34.1% and 33.3%, respectively).

Preventing falls among community-dwelling older persons: results from a randomized trial.

A randomized trial of falls prevention program that addressed home safety, exercise, and behavioral risks was conducted with 3,182 independently living HMO members age 65 and older. The intervention decreased the odds of falling by 0.85, but only reduced the average number of falls among those who fell by 7%. The effect was strongest among men age 75 and older. The likelihood of avoiding falls requiring medical treatment was not significantly affected by the intervention. We conclude that the intervention dose was not of sufficient intensity or duration to have a marked protective effect on older persons. Future research should focus on more intensive intervention approaches because serious falls do not appear to be amendable to low-intensity environment/behavioral efforts.

Implementing a year-long, worksite-based incentive program for smoking cessation.

BACKGROUND: There have been few reports of the process of implementing ongoing worksite health promotion programs. This article describes the implementation of a year-long smoking cessation program in nine worksites employing a total of approximately 700 smokers. METHODS: Issues discussed include: forming a partnership with organizations, design of the multicomponent incentive intervention, program promotion, maintaining participation, and the need to modify program components over time. RESULTS: The program produced high participation rates (29% of smokers joined the program) and moderate cessation rates among participants (during the last half of the program, monthly cessation rates averaged 20%). There was marked variability across worksites on both participation and cessation, and qualitative features of organizations associated with outcome are discussed. DISCUSSION: The importance of working with employee steering committees to tailor health promotion programs to fit the organization is discussed. The article concludes with recommendations for implementation of similar programs.

Results of a year-long incentives-based worksite smoking-cessation program.

This study evaluated the impact of a year-long incentives-based worksite smoking-cessation program. Nineteen moderate-sized worksites, employing a total of approximately 1100 smokers, were randomized to Incentive or No Incentive conditions. All identified smokers in the worksite were considered as subjects, whether or not they participated in the intervention. Analyses were conducted at both the worksite and individual level, and using both self-reported and biochemically validated cessation as endpoints. The incentive program did not significantly improve cessation rates at either the 1-year or 2-year follow-up assessments. We conclude that more broadly focused interventions that also address worksite smoking policies, skills training, and cessation resources, or programs that target additional risk factors are needed to substantially enhance quit rates.

Brief assessments of dietary behavior in field settings.

Our research team is involved in ongoing research in both worksites and medical office settings. These settings offer great potential for reaching individuals who would not otherwise participate in health promotion, but they also place considerable constraints on assessment time and efforts, especially if one's goal is to attract a high and representative proportion of employees or patients. This paper reports on our experience with measures of dietary behavior in these two settings. We found it problematic to collect detailed assessments such as 4-day food records or comprehensive food frequency/history checklists in worksites or medical office settings using population-based samples. Instead, we recommend and provide data on the utility of a dietary-fat screening instrument, and on the Food Habits Questionnaire (FHQ-Kristal, Shattuck, & Henry, 1990), a brief measure of dietary behaviors associated with high-fat eating patterns. The FHQ, in particular, was found to correlate well with other more costly and time-consuming methods of assessment, to be reliable and responsive to intervention effects, and to provide behavioral targets for intervention. The strengths and limitations of these measures for tailoring intervention and assessing outcomes are discussed.

Tobacco cessation interventions in health care settings: rationale, model, outcomes.

Health care settings provide opportunities to reach populations of tobacco users with personalized cessation assistance. We describe a model for doing so which emphasizes a team approach, minimizes the burden on clinicians, and uses brief counseling by allied professionals, videos, written materials, and telephone calls to augment clinician advice. The model has been implemented in several diverse settings including outpatient, inpatient, and dental clinic managed care; fee-for-service dentistry and pediatric practices; and planned parenthood clinics. Data from several randomized trials support the effectiveness of the approach. The brief, low-intensity interventions derived from the model appear to be sustainable on a routine basis in many settings.

Biochemical validation of smoking status: pros, cons, and data from four low-intensity intervention trials.

Biochemical validation of smoking status has long been considered essential, but recent reports have questioned its utility in certain kinds of field trials. We describe efforts to biochemically validate self-reports of smoking cessation from participants in four large-scale randomized trials in outpatient clinics, hospitals, worksites, and dental clinics. These studies included over 5,000 adults smokers who participated in the population-based low-intensity intervention evaluations. At a 1-year follow-up, 798 subjects reported no tobacco use. We attempted to verify these reports using saliva continine/carbon monoxide validation procedures. Overall, there was a moderately high nonparticipation rate (27%), a low disconfirmation rate (4%), and a high self-reported relapse rate (12%) in the interval between survey and biochemical validation. There were no differences between intervention and control conditions on any of the above variables. Longer durations of self-reported abstinence were strongly related to increased probability of biochemical confirmation. Differences in results across projects were related to how biochemical validation was conducted. These results, as well as statistical power considerations, raise questions about whether biochemical validation procedures are practical, informative, or cost-effective in such population-based, low-intensity intervention research.

Screening and brief intervention for hazardous drinking in an HMO: effects on medical care utilization.

This study examined whether a brief intervention to reduce hazardous alcohol consumption among primary care patients reduced use of medical care. In a parent, randomized controlled trial, at-risk drinkers identified in HMO outpatient waiting rooms were randomly assigned to receive usual care or brief clinician advice plus a 15-minute motivational counseling session. The current study (n = 514) examined the groups' use of outpatient and inpatient medical services during two years after intervention. Although the intervention reduced alcohol consumption at six-month follow-up, intervention and control groups made similar numbers of outpatient visits (M = 17.7 vs. 18.3, respectively; p = .47), were equally likely to be hospitalized (21.2% vs. 22.0%; p = .81), and among those hospitalized, had similar lengths of stay (4.7 vs. 6.6 days; p = .37). Although brief interventions to reduce hazardous drinking may potentially reduce medical care utilization, more evidence is needed to substantiate their practicality and cost-effectiveness.

Implementation of "Open Airways" as an educational intervention for children with asthma in an HMO.

This article describes the adaptation and implementation of an existing pediatric asthma-management educational program, Open Airways, for members of a large group practice health maintenance organization. Seventy-four children ages 4 to 14 years and their families were randomized into one of seven class cohorts as part of a larger study of pediatric asthma management. The Open Airways program was modified to increase the emphasis on behavioral change and medication information and to reflect the different sociodemographic makeup of the population, compared with that for which the program was developed. Of the 74 families, 62 attended at least one class, and 47 of these attended five or more classes. Evaluations after classes suggest an increase in parental confidence in managing their child's asthma and an earlier use of medications. Health care providers may be able to adapt similar programs for successful use with their populations.

Nicotine chewing gum use in the outpatient care setting.

BACKGROUND: The purpose of this study was to assess nicotine gum use when prescribed in a nonresearch, routine outpatient setting. Special attention was given to comparing actual use patterns with established guidelines for use based on clinical research. METHODS: A randomly selected group of 612 patients who had received a prescription for nicotine gum during an 18-month period were surveyed regarding their smoking history and use of the gum. RESULTS: Most of the gum prescriptions (75%) were requested by patients rather than recommended by medical care providers. Less than one half of the users were heavy smokers. The reported amount of gum used was small, with more than one half reporting consumption of one box or less, and about one third reporting use of the gum for only 1 week or less. Larger amounts of gum use, however, were associated with abstinence from tobacco. Only one in 20 users attended a structured behavioral treatment program while using the gum. Over one half of the patients reported using nicotine gum to help them cut down on, rather than quit, smoking. CONCLUSIONS: Only a small percentage of the patients used the nicotine gum according to the established guidelines, and most of the patients used the gum in ways that have been shown to be ineffective for smoking cessation. Providers should educate their patients in the techniques that maximize the use and effectiveness of nicotine gum in smoking cessation.