Matthew S. Mayo

Physical Activity Across the Curriculum (PAAC): a randomized controlled trial to promote physical activity and diminish overweight and obesity in elementary school children

BACKGROUND Physical Activity Across the Curriculum (PAAC) was a three-year cluster randomized controlled trial to promote physical activity and diminish increases in overweight and obesity in elementary school children. METHODS Twenty-four elementary schools were cluster randomized to the Physical Activity Across the Curriculum intervention or served as control. All children in grades two and three were followed to grades four and five. Physical Activity Across the Curriculum promoted 90 min/wk of moderate to vigorous intensity physically active academic lessons delivered by classroom teachers. Body Mass Index was the primary outcome, daily Physical activity and academic achievement were secondary outcomes. RESULTS The three-year change in Body Mass Index for Physical Activity Across the Curriculum was 2.0+/-1.9 and control 1.9+/-1.9, respectively (NS). However, change in Body Mass Index from baseline to 3 years was significantly influenced by exposure to Physical Activity Across the Curriculum. Schools with > or =75 min of Physical Activity Across the Curriculum/wk showed significantly less increase in Body Mass Index at 3 years compared to schools that had <75 min of Physical Activity Across the Curriculum (1.8+/-1.8 vs. 2.4+/-2.0, p=0.02). Physical Activity Across the Curriculum schools had significantly greater changes in daily Physical activity and academic achievement scores. CONCLUSIONS The Physical Activity Across the Curriculum approach may promote daily Physical activity and academic achievement in elementary school children. Additionally, 75 min of Physical Activity Across the Curriculum activities may attenuate increases in Body Mass Index.

The frequency of Barrett's esophagus in high-risk patients with chronic GERD.

BACKGROUND The reported frequency of Barretts esophagus (BE) in patients with reflux symptoms varies from 5% to 15%. The exact frequency of long-segment BE (LSBE) (>3 cm) and short-segment BE (SSBE) (<3 cm) in patients with chronic symptoms of GERD is uncertain. The aim of this study was to determine the frequency of LSBE and SSBE in consecutive patients presenting for a first endoscopic evaluation with GERD as the indication. METHODS Consecutive patients presenting to the endoscopy unit of a Veterans Affairs Medical Center for a first upper endoscopy with the indication of GERD were prospectively evaluated. Demographic information (gender, race, age), data on tobacco use and family history of esophageal disease, and body mass index (BMI) were recorded for all patients. Before endoscopy, all patients completed a validated GERD questionnaire. The diagnosis of BE was based on the presence of columnar-appearing mucosa in the distal esophagus, with confirmation by demonstration of intestinal metaplasia in biopsy specimens. All patients with erosive esophagitis on the initial endoscopy underwent a second endoscopy to document healing and to rule-out underlying BE. Patients with a history of BE, alarm symptoms (dysphagia, weight loss, anemia, evidence of GI bleeding), or prior endoscopy were excluded. RESULTS A total of 378 consecutive patients with GERD (94% men, 86% white; median age 56 years, range 27-93 years) were evaluated. A diagnosis of BE was made in 50 patients (13.2%). The median length of Barretts esophagus (BE) was 1.0 cm (range 0.5-15.0 cm). Of the patients with BE, 64% had short-segment BE (SSBE) (overall SSBE frequency 8.5%). The overall frequency of long-segment BE (LSBE) was 4.8%. A hiatal hernia was detected in 62% of the patients with BE. Of the 50 patients with BE (median age 62 years, range 29-81 years), 47 (94%) were men and 98% were white. Eighteen patients (36%) were using tobacco at the time of endoscopy; 23 (46%) were former users. The median body mass index (BMI) of patients with BE was 27.3 (overweight). There were no significant differences between patients with LSBE and SSBE with respect to age, gender, ethnicity, BMI, and GERD symptom duration. CONCLUSIONS The frequency of BE in a high-risk patient group (chronic GERD, majority white men, age > 50 years) who sought medical attention is 13.2%, with the majority (64%) having SSBE. These data suggest that the frequency of BE in patients with GERD has not changed. The true prevalence of BE in the general population, including those who do not seek care, is undoubtedly lower, currently and historically. The majority of patients with BE are overweight and have a hiatal hernia. Demographic data for patients with LSBE and SSBE are similar, indicating that these are a continuum of the same process.

Duration of television watching is associated with increased body mass index

OBJECTIVE To assess the effect of television viewing on subsequent change in body mass index (BMI=kg/m(2)) percentiles (BMI%) in adolescence. STUDY DESIGN Data were drawn from the California Teen Longitudinal Survey of adolescents 12 to 17 years old with baseline assessment in 1993 and follow-up in 1996. Self-reported height and weight were used to calculate BMI and derive age-specific and sex-specific BMI%. Hours of television watched per day were obtained at baseline (BTV). The relations of BTV and BMI percentiles both at baseline and after 3 years were assessed with linear regression modeling. RESULTS Of 2223 adolescents (52% male, 68% white), 5.85% (n=130) were overweight (BMI > or =95th percentile) at baseline and 5.40% (n=120) at follow-up. Mean BTV was 2.85 (SD, 1.98). In adjusted models, with each additional hour of BTV, the baseline BMI% increased by.9, and the follow-up BMI% increased by.47. Adolescents who watched more than 2 hours of television a day were twice as likely to be overweight at follow-up as adolescents who watched < or =2 hours. CONCLUSIONS Television viewing leads to a subsequent increase in BMI percentiles and overweight. Efforts to decrease overweight should consider interventions to reduce television time.

Single-Dose and Multiple-Dose Administration of Indole-3-Carbinol to Women: Pharmacokinetics Based on 3,3′-Diindolylmethane

We have completed a phase I trial in women of the proposed chemopreventive natural product indole-3-carbinol (I3C). Women received oral doses of 400, 600, 800, 1,000, and 1,200 mg I3C. Serial plasma samples were analyzed by high-performance liquid chromatography-mass spectrometry for I3C and several of its condensation products. I3C itself was not detectable in plasma. The only detectable I3C-derived product was 3,3′-diindolylmethane (DIM). Mean Cmax for DIM increased from 61 ng/mL at the 400-mg I3C dose to 607 ng/mL following a 1,000-mg dose. No further increase was observed following a 1,200-mg dose. A similar result was obtained for the area under the curve, which increased from 329 h ng/mL at the 400-mg dose to 3,376 h ng/mL after a 1,000-mg dose of I3C. Significant interindividual quantitative variation was seen in plasma DIM values within each dosing group, but the overall profiles were qualitatively similar, with no quantifiable DIM before dosing, tmax at ∼2 h, and DIM levels near or below 15 ng/mL (the limit of quantitation), by 24 h. Different results were obtained for 14 subjects who received a 400-mg dose of I3C after 8 weeks of twice-daily I3C dosing. Although the predose sampling occurred at least 12 h after the last known ingestion of I3C, 6 of 14 subjects exhibited Cmax for DIM in their predose plasma. Despite this high initial value, plasma DIM for all subjects decreased to near or below the limit of quantitation within the 12-h sampling period. Possible reasons for this disparity between apparent t1/2 of DIM and the high predose values are discussed. (Cancer Epidemiol Biomarkers Prev 2006;15(12):2477–81)

A Phase I Study of Indole-3-Carbinol in Women: Tolerability and Effects

We completed a phase I trial of indole-3-carbinol (I3C) in 17 women (1 postmenopausal and 16 premenopausal) from a high-risk breast cancer cohort. After a 4-week placebo run-in period, subjects ingested 400 mg I3C daily for 4 weeks followed by a 4-week period of 800 mg I3C daily. These chronic doses were tolerated well by all subjects. Hormonal variables were measured near the end of the placebo and dosing periods, including determination of the urinary 2-hydroxyestrone/16α-hydroxyestrone ratio. Measurements were made during the follicular phase for premenopausal women. Serum estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin showed no significant changes in response to I3C. Caffeine was used to probe for cytochrome P450 1A2 (CYP1A2), N-acetyltransferase-2 (NAT-2), and xanthine oxidase. Comparing the results from the placebo and the 800 mg daily dose period, CYP1A2 was elevated by I3C in 94% of the subjects, with a mean increase of 4.1-fold. In subjects with high NAT-2 activities, these were decreased to 11% by I3C administration but not altered if NAT-2 activity was initially low. Xanthine oxidase was not affected. Lymphocyte glutathione S-transferase activity was increased by 69% in response to I3C. The apparent induction of CYP1A2 was mirrored by a 66% increase in the urinary 2-hydroxyestrone/16α-hydroxyestrone ratio in response to I3C. The maximal increase was observed with the 400 mg daily dose of I3C, with no further increase found at 800 mg daily. If the ratio of hydroxylated estrone metabolites is a biomarker for chemoprevention, as suggested, then 400 mg I3C daily will elicit a maximal protective effect.

Peripheral insulin and brain structure in early Alzheimer disease

Objective: Accumulating evidence suggests insulin and insulin signaling may be involved in the pathophysiology of Alzheimer disease (AD). The relationship between insulin-mediated glucoregulation and brain structure has not been assessed in individuals with AD. Methods: Nondemented (Clinical Dementia Rating [CDR] 0, n = 31) and early stage AD (CDR 0.5 and 1, n = 31) participants aged 65 years and older had brain MRI to determine whole brain and hippocampal volume and 3-hour IV glucose tolerance tests to determine glucose and insulin area under the curve (AUC). Linear regression models were used to assess the relationship of insulin and glucose with brain volume, cognition, and dementia severity. Results: In early AD, insulin and glucose AUCs were related to whole brain (insulin β = 0.66, p < 0.001; glucose β = 0.45, p < 0.01) and hippocampal volume (insulin β = 0.42, p < 0.05; glucose β = 0.46, p < 0.05). These relationships were independent of age, sex, body mass index, body fat, cardiorespiratory fitness, physical activity, cholesterol, and triglycerides. Insulin AUC, but not glucose, was associated with cognitive performance in early AD (β = 0.40, p = 0.04). Insulin AUC was associated with dementia severity (Pearson r = −0.40, p = 0.03). Glucose and insulin were not related to brain volume or cognitive performance in nondemented individuals. Conclusions: Increased peripheral insulin is associated with reduced Alzheimer disease (AD)–related brain atrophy, cognitive dysfunction, and dementia severity, suggesting that insulin signaling may play a role in the pathophysiology of AD.

Cytokine and Antibody Responses in Women Infected with Neisseria gonorrhoeae: Effects of Concomitant Infections

The levels of interleukin (IL)-1, IL-6, IL-8, IL-10, and transforming growth factor-beta in sera and genital tract secretions from women with gonococcal cervicitis and other genital infections were examined. Cytokines were not elevated in genital secretions from gonococcus-infected compared with uninfected patients. The level of serum IL-6 was higher in gonococcus-infected than in uninfected patients at recruitment. Serum, but not local, IL-1 and IL-6 levels were elevated in patients concomitantly infected with Trichomonas vaginalis or Chlamydia trachomatis in addition to Neisseria gonorrhoeae compared with levels in patients infected with any single organism. Concomitant infection altered neither the total immunoglobulin concentrations nor the levels of antigonococcal antibodies in serum or local secretions. The results suggest that N. gonorrhoeae induces only a limited cytokine and antibody response during uncomplicated cervical infections; however, the presence of other sexually transmitted disease-causing organisms can alter the systemic cytokine but not the antigonococcal antibody levels.

Physical activity across the curriculum: year one process evaluation results

BackgroundPhysical Activity Across the Curriculum (PAAC) is a 3-year elementary school-based intervention to determine if increased amounts of moderate intensity physical activity performed in the classroom will diminish gains in body mass index (BMI). It is a cluster-randomized, controlled trial, involving 4905 children (2505 intervention, 2400 control).MethodsWe collected both qualitative and quantitative process evaluation data from 24 schools (14 intervention and 10 control), which included tracking teacher training issues, challenges and barriers to effective implementation of PAAC lessons, initial and continual use of program specified activities, and potential competing factors, which might contaminate or lessen program effects.ResultsOverall teacher attendance at training sessions showed exceptional reach. Teachers incorporated active lessons on most days, resulting in significantly greater student physical activity levels compared to controls (p < 0.0001). Enjoyment ratings for classroom-based lessons were also higher for intervention students. Competing factors, which might influence program results, were not carried out at intervention or control schools or were judged to be minimal.ConclusionIn the first year of the PAAC intervention, process evaluation results were instrumental in identifying successes and challenges faced by teachers when trying to modify existing academic lessons to incorporate physical activity.

Aerobic exercise alone results in clinically significant weight loss for men and women: Midwest Exercise Trial-2

Exercise is recommended by public health agencies for weight management; however, the role of exercise is generally considered secondary to energy restriction. Few studies exist that have verified completion of exercise, measured the energy expenditure of exercise, and prescribed exercise with equivalent energy expenditure across individuals and genders.

Successful recruitment of minorities into clinical trials: The Kick It at Swope project

Ethnic minorities are often underrepresented in clinical trials, and their recruitment can challenge researchers. Developing and communicating effective and efficient recruitment strategies may help researchers enroll more minorities into research studies. Kick It at Swope was a double-blind, randomized trial that evaluated bupropion for smoking cessation among 600 adult African Americans who smoked 10 or more cigarettes a day. Proactive recruitment strategies (in-person appeals by study staff and health care providers) and reactive recruitment strategies (disseminating information that asked people to call a study hotline) were implemented sequentially in an additive fashion over 16 months. Resulting patterns of recruitment are described and the two phases are compared based on their relative effectiveness, efficiency, and cost. More enrollees were recruited in the reactive phase (n=534) than in the proactive phase (n=66). Those recruited in the reactive phase were more likely to be eligible (OR=4.8) and more likely to be enrolled (OR=4.2) than those recruited in the proactive phase. Participants recruited in the reactive phase reported significantly higher levels of education and income, better health, and significantly lower indicators of depression and life hassles, compared with those recruited in the proactive phase. The reactive recruitment phase was less expensive than the proactive recruitment phase (22 US Dollars/enrollee vs. 159 US Dollars/enrollee). Reactive recruitment strategies added to multiple proactive clinic-based recruitment strategies were more effective, more efficient, and less costly than proactive recruitment alone. Close monitoring combined with the use of multiple recruitment methods and flexible recruitment plans can lead to successful, efficient, and low-cost recruitment of minorities into clinical trials.