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Christopher Ochner

    Christopher Ochner

    The Body Shape Questionnaire (BSQ) is a widely used measure of body shape concerns that was originally designed for use with women but has more recently been used with boys and men. The latter use may be problematic, given that no... more
    The Body Shape Questionnaire (BSQ) is a widely used measure of body shape concerns that was originally designed for use with women but has more recently been used with boys and men. The latter use may be problematic, given that no previous study has demonstrated sex invariance for BSQ scores. To determine the extent to which BSQ scores are sex invariant, we asked Portuguese-speaking women ( n = 1,613) and men ( n = 871) to complete the full BSQ (34 items). Confirmatory factor analysis indicated that a hypothesized 32-item model of BSQ scores and shorter versions had acceptable fit indices in women and men, separately. However, multigroup confirmatory factor analysis showed that these BSQ model scores had configural but not metric, scalar, or strict sex invariance. Differential item analysis indicated significant item-functioning differences on 19 of the 32 retained BSQ items. Thus, BSQ scores are not sex invariant, making problematic the results of previous studies that have compare...
    Entamoeba histolytica is the responsible parasite of amoebiasis and remains one of the top three parasitic causes of mortality worldwide. With increased travel and emigration to developed countries, infection is becoming more common in... more
    Entamoeba histolytica is the responsible parasite of amoebiasis and remains one of the top three parasitic causes of mortality worldwide. With increased travel and emigration to developed countries, infection is becoming more common in nonendemic areas. Although the majority of individuals infected with E. histolytica remain asymptomatic, some present with amoebic colitis and disseminated disease. As more is learned about its pathogenesis and the host’s immune response, the potential for developing a vaccine holds promise. This narrative review outlines the current knowledge regarding E. histolytica and E. dispar and insight in the development of a vaccine.
    To refine the biobehavioral markers of binge eating disorder (BED). We conducted fMRI brain scans using images of high energy processed food (HEPF), low energy unprocessed food (LEUF), or non-foods (NF) in 42 adults (obese with BED [obese... more
    To refine the biobehavioral markers of binge eating disorder (BED). We conducted fMRI brain scans using images of high energy processed food (HEPF), low energy unprocessed food (LEUF), or non-foods (NF) in 42 adults (obese with BED [obese -BED; n=13] and obese with no BED [obese non-BED; n=29]) selected via ads. Two blood oxygenated level dependent (BOLD) signal contrast maps were examined: food versus nonfood, and HEPF versus LEUF. In addition, score differences on the disinhibition scale were correlated with BOLD signals. food versus nonfood showed greater BOLD activity for BED in emotional, motivational and somatosensory brain areas: insula, anterior cingulate cortex (ACC), Brodmann areas (BA) 19 & 32, inferior parietal lobule (IPL), posterior cingulate cortex (PCC), and lingual, postcentral, middle temporal and cuneate gyri (p≤0.005; k≥88). HEPF versus LEUF showed greater BOLD activity for BED in inhibitory brain regions: BA 6, middle and superior frontal gyri (p<0.01; k≥119)...
    MAP (MUTYH-associated polyposis) is a syndrome, described in 2002, which is associated with colorectal adenomas, with enhanced colorectal carcinogenesis. This review synthesizes the available literature on MAP and outlines its... more
    MAP (MUTYH-associated polyposis) is a syndrome, described in 2002, which is associated with colorectal adenomas, with enhanced colorectal carcinogenesis. This review synthesizes the available literature on MAP and outlines its pathogenesis, association with colorectal tumorigenesis, screening, treatment, and the subtle differences between it and its close cousins—FAP and AFAP. The preponderance of data is collected using MAP guidelines. However, although AFAP and MAP appear similar, potentially important distinctions exist, warranting targeted diagnostic criteria and treatment approaches. We suggest that it may be prudent to screen for MAP earlier than in current clinical practice, as it has been shown that sequence variants are associated with more severe disease, presenting with an earlier onset of colorectal cancer. Finally, we issue a call-to-action for much-needed further data to establish clear clinical and diagnostic criteria.
    To evaluate the psychometric properties of the male body dissatisfaction scale (MBDS) in Brazilian and Portuguese university students; to present a reduced model of the scale; to compare two methods of computing global scores for... more
    To evaluate the psychometric properties of the male body dissatisfaction scale (MBDS) in Brazilian and Portuguese university students; to present a reduced model of the scale; to compare two methods of computing global scores for participants' body dissatisfaction; and to estimate the prevalence of participants' body dissatisfaction. A total of 932 male students participated in this study. A confirmatory factor analysis (CFA) was used to assess the scale's psychometric properties. Multi-group analysis was used to test transnational invariance and invariance in independent samples. The body dissatisfaction score was calculated using two methods (mean and matrix of weights in the CFA), which were compared. Finally, individuals were classified according to level of body dissatisfaction, using the best method. The MBDS model did not show adequate fit for the sample and was, therefore, refined. Thirteen items were excluded and two factors were combined. A reduced model of 12 ...
    Background. Sexually transmitted infections (STIs) are common among adolescents, and multiple STIs over one's lifetime can increase health risks. Few studies have assessed lifetime STI prevalence. This study evaluates... more
    Background. Sexually transmitted infections (STIs) are common among adolescents, and multiple STIs over one's lifetime can increase health risks. Few studies have assessed lifetime STI prevalence. This study evaluates minority, underserved adolescents' self-reported lifetime STI history and objective STI rates. Methods. Lifetime STI rates of female patients at an urban adolescent health center were obtained from self-administered questionnaires. Additionally, STI test results were retrieved from electronic medical records. Results. Patients reported a high lifetime prevalence of STIs. By comparing self-report and objective data, underreporting was identified for chlamydia, gonorrhea, and herpes. Conclusions. STI rates in at-risk adolescent females are higher than in the general population and remain elevated over time. Lifetime STI reports could expand our understanding of sexual health and should be further studied. Underreporting, which may increase health risks and hinder...
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    ... Physiol Behav. 2004;81:735-740. 4. Geliebter A, Ladell T, Logan M, Schneider T, Sharafi M, Hirsch J. Responsivity to food stimuli in obese and lean binge eaters using func-tional MRI. Appetite. 2006;46:31-35. 5. Walsh T. (ed). The... more
    ... Physiol Behav. 2004;81:735-740. 4. Geliebter A, Ladell T, Logan M, Schneider T, Sharafi M, Hirsch J. Responsivity to food stimuli in obese and lean binge eaters using func-tional MRI. Appetite. 2006;46:31-35. 5. Walsh T. (ed). The current status of binge eating disorder. ...
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    Previous studies suggest that individuals with body mass index (BMI) above versus below 60 kg/m(2) attain lower percentage of excess weight loss (%EWL) after bariatric surgery. The objectives of this study were to (1) test whether... more
    Previous studies suggest that individuals with body mass index (BMI) above versus below 60 kg/m(2) attain lower percentage of excess weight loss (%EWL) after bariatric surgery. The objectives of this study were to (1) test whether conclusions drawn about the effect of preoperative BMI on postoperative weight loss depend on the outcome measure, (2) test for evidence of a threshold effect at BMI = 60 kg/m(2), and (3) test the effect from surgery to 12-month follow-up, relative to 12- to 36-month follow-up. Retrospective analyses of participants grouped according to preoperative BMI: 35-39.9 (n = 232); 40-49.9 (n = 1166); 50-59.9 (n = 429);≥60 (n = 166). As anticipated, individuals with higher versus lower preoperative BMI had greater total weight loss but lower %EWL at all postoperative time points (all, P<.0005). However, these individuals also had lower percentage of initial weight loss (%IWL) at all time points beyond 1 month postsurgery (all, P<.0005). From 12- to 36-months, individuals with BMI 35-39.9 had 3.2±14.3 %IWL (P<.0001); 40-49.9 had 1.0±8.9 %IWL (P<.0005); 50-59.9 had-2.4±10.0 %IWL (P<.0005); and≥60 had-3.6±11.5 %IWL (P<.0005). Overall F3,1989 = 20.2, P< .0005. Conclusions drawn about the effect of preoperative BMI may depend on the outcome measure. A dosage effect of preoperative BMI was apparent, with heavier individuals showing lower percentages of initial and excess weight loss, regardless of BMI above or below 60 kg/m(2). Finally, this effect was particularly apparent after the initial 12-month rapid weight loss phase, when less obese (BMI<50) individuals continued losing weight, while heavier individuals (BMI≥50) regained significant weight.
    Whether and how sex and age affect bariatric-surgery outcome is poorly understood. Estrogens regulate body composition in women and animals, and increase weight loss in a rodent model of gastric bypass, suggesting that premenopausal women... more
    Whether and how sex and age affect bariatric-surgery outcome is poorly understood. Estrogens regulate body composition in women and animals, and increase weight loss in a rodent model of gastric bypass, suggesting that premenopausal women may lose more weight following bariatric surgery. One thousand three hundred fifty-six female gastric-bypass or gastric-banding patients were retrospectively grouped as 20-45 years old (presumptively premenopausal; n = 1,199) and 55-65 years old (presumptively postmenopausal; n = 157). Mixed-model ANCOVA followed by Bonferroni-corrected t tests were used to categorically test the effect of age on percent excess body weight loss (%EBWL) at 1 and 2 years post-surgery, controlling for preoperative EBW and surgery type. Age effects were also tested dimensionally in all women and in 289 male patients. Twenty- to forty-five-year-old women showed greater %EBWL 1 and 2 years post-surgery than 55-65-year-old women (p's < 0.0005). No age effect was detected in 20-25- vs. 30-35-, 30-35- vs. 40-45-, or 20-25- vs. 40-45-year-old women (p's > 0.2) This age effect was detected only after gastric banding, with 20-45-year-old women losing ∼7 kg more than 55-65-year-old women after 2 years. Dimensional analysis confirmed a significant inverse effect of age on bariatric surgery outcome in women, but did not detect any effect in men. Results indicate that 55-65-year-old women lose less weight than 20-45-year-old women in the initial 2 years after bariatric surgery, especially gastric banding; this may be mediated by age- or menopause-associated changes in physical activity, energy expenditure, or energy intake.
    Reductions in mesolimbic responsivity have been noted following Roux-en-Y gastric bypass (RYGB; Ochner et al., 2011a). Given potential for postoperative increases in postprandial gut (satiety) peptides to affect mesolimbic neural... more
    Reductions in mesolimbic responsivity have been noted following Roux-en-Y gastric bypass (RYGB; Ochner et al., 2011a). Given potential for postoperative increases in postprandial gut (satiety) peptides to affect mesolimbic neural responsivity, we hypothesized that: (1) post RYGB changes in mesolimbic responsivity would be greater in the fed relative to the fasted state and; (2) fasted vs. fed state differences in mesolimbic responsivity would be greater post-relative to pre-surgery. fMRI was used to asses neural responsivity to high- and low-calorie food cues in five women 1 mo pre- and 1 mo post-RYGB. Scans were repeated in fasted and fed states. Significant post RYGB decreases in the insula, ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) responsivity were found in the fasted state. These changes were larger than neural changes in the fed state, which were non-significant. Preoperatively, fasted vs. fed differences in neural responsivity were greater in the precuneus, with large but nonsignificant clusters in the vmPFC and dlPFC. Postoperatively, however, no fasted vs. fed differences in neural responsivity were noted. Results were opposite to that predicted and appear inconsistent with the initial hypothesis that postoperative increases in postprandial gut peptides are the primary driver of postoperative changes in neural responsivity.
    This study examined relationships between changes in dietary calcium intake, energy intake, and body weight following a weight loss diet. One hundred three overweight or obese women lost weight over 22 wk. Dietary calcium and energy... more
    This study examined relationships between changes in dietary calcium intake, energy intake, and body weight following a weight loss diet. One hundred three overweight or obese women lost weight over 22 wk. Dietary calcium and energy intake were assessed using the Block 98 FFQ (Block) and 5-d food records (FR) at intervention end and 6- and 18-mo follow-up. Pearson correlations were used to relate changes in dietary calcium to energy intake. We used regression analyses to examine relationships between changes in dietary calcium, energy intake, and weight regain. Changes in dietary calcium and energy intake were correlated (r ¼ 0.32; P ¼ 0.033), but neither variable alone predicted weight regain. From 6- to 18-mo follow-up, greater dietary calcium intake inversely predicted weight regain when controlling for changes in energy intake (P ¼ 0.048 Block and 0.025 FR), whereas higher energy intake positively predicted weight regain when controlling for changes in dietary calcium intake (P ...
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    There is debate about the additive effects of exercise in conjunction with diet to treat obesity, and not much is known about the differential effects of strength versus aerobic training. This randomized controlled trial examined the... more
    There is debate about the additive effects of exercise in conjunction with diet to treat obesity, and not much is known about the differential effects of strength versus aerobic training. This randomized controlled trial examined the effects of diet plus strength training, diet plus aerobic training, or diet only on metabolic risk factors associated with obesity. Eighty-one overweight and obese participants completed the 8-week intervention. All participants received an energy-restrictive formula diet with an energy content based on 70% of measured resting metabolic rate (RMR). Participants assigned to an exercise group trained 3 days/week under supervision. Anthropometrics and fasting hormones were assessed pre- and post-intervention. Mean weight loss (8.5 ± 4.3kg SD) did not differ between groups nor did reductions in BMI or body fat, although the diet plus strength training group showed marginally greater lean mass retention. There were significant improvements in the values and ...