Body size and the risk of colon cancer in a large case-control study.
Caan BJ. Coates AO. Slattery ML. Potter JD. Quesenberry CP Jr. Edwards SM.
Kaiser Permanente Medical Care Program of Northern California, Division of Research, Oakland 94611, USA.
OBJECTIVE: To investigate the risks of height, weight and body fat distribution associated with colon cancer in subcategories of gender, age and site in the colon. Interaction with family history of colorectal cancer is also examined. DESIGN: Case-control study of diet, anthropometry and colon cancer risk. SUBJECTS: Nineteen hundred and eighty-three colon cancer cases (age 30-79 y) and 2400 age and gender matched population controls. MEASUREMENTS: Height, weight and waist and hip circumferences were obtained by trained interviewers. Body Mass Index (BMI) and Waist-Hip Ratio (WHR) were calculated. RESULTS: Of all anthropometric measurements examined, only BMI was consistently associated with an increased risk of colon cancer. The test for trend for BMI was significant for men and women overall and for the majority of subgroups examined. In younger persons those with a family history of colorectal cancer had a greater risk of colon cancer associated with BMI (Men odds ratio (OR) = 7.76, 95% confidence interval (CI) 2.60, 23.1; Women OR = 4.85, 95% CI 2.33, 10.12) comparing the third tertile to the first, than those with no family history (Men OR = 1.70, 95% CI 1.25, 2.32; Women OR = 1.53, 95% CI 1.22, 1.92). WHR, after controlling for BMI was not associated with colon cancer in men, and was associated with a slight increase in women (primarily in those with distal tumors). CONCLUSION: This study contributes to mounting evidence that excess weight is associated with an increased risk of colon cancer.
Liver abnormalities in severely obese subjects: effect of drastic weight loss after gastroplasty.
Luyckx FH. Desaive C. Thiry A. Dewe W. Scheen AJ. Gielen JE. Lefebvre PJ.
Department of Clinical Chemistry, CHU Sart Tilman, University of Liege, Belgium.
OBJECTIVE: To examine the factors associated with liver steatosis in severely obese subjects and to test the potential reversibility of fatty liver after weight loss. DESIGN: Retrospective clinical study. SUBJECT: 528 obese patients before bariatric surgery and 69 obese subjects of the initial cohort evaluated before and 27+/-15 months after gastroplasty. MEASUREMENTS: Fatty deposition (scored as mild, moderate or severe) and inflammatory changes were evaluated in liver biopsies; clinical (body mass index (BMI), age, gender, duration of obesity) and biological (glucose, triglycerides, liver enzymes) parameters were related to histological findings. RESULTS: 74% of the 528 biopsies showed fatty change, estimated as mild in 41% of cases, moderate in 32% and severe in 27%. The prevalence of steatosis was significantly higher in men than in women (91% vs 70%, P = 0.001) and in patients with impaired glucose tolerance or type 2 diabetes compared with nondiabetics (89% vs 69% P = 0.001). The severity of the steatosis was associated with BMI (P = 0.002) but not with the duration of obesity or the age of the patient. When compared with patients without fatty change, those with liver steatosis had significantly higher fasting plasma glucose (5.5 mmol/l vs 5.1 mmol/l, P = 0.007) and triglycerides (1.8 mmol/l vs 1.3 mmol/l, P = 0.002). Mean serum liver enzyme activities (alkaline phosphatase, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl-transpeptidase (gammaGT) were significantly (P < 0.001) increased in patients with fatty change but remained within laboratory reference values. In the 69 patients who have been evaluated after a marked weight reduction (-32+/-19kg), 45% of the biopsies were considered as normal (vs 13% before, P < 0.001) while pure fatty change was still observed in 38% of the patients (vs 83% before, P = 0.001). However, the severity of the steatosis was significantly (P < 0.001) reduced (mild: 62% vs 21%; moderate: 23% vs 37%; severe: 15% vs 42%). In addition, a significant increase of hepatitis was observed in 26% of the biopsies (vs 14% before, P < 0.05). CONCLUSIONS: Liver steatosis in obese subjects is associated with men, diabetic status, BMI, higher fasting glucose and hypertriglyceridaemia. Postgastroplasty weight loss reduces liver steatosis, but seems to increase the incidence of inflammatory lobular hepatitis.
The pursuit of thinness: a study of Dublin schoolgirls aged 15 y.
Ryan YM. Gibney MJ. Flynn MA.
Department of Biological Sciences, Dublin Institute of Technology, Ireland.
Despite increasing trends in the prevalence of overweight and obesity, fatness phobia is common during female adolescence. This study has demonstrated a high level of dissatisfaction with body weight in a sample of Dublin schoolgirls aged 15 y. Of 420 subjects, 59% reported that they wanted to be slimmer and 68% had previously tried to lose weight. Contrary to expectations, overweight girls were not found to hold the monopoly on such dissatisfactions. Normal weight and even underweight girls also expressed a desire to be thinner and reported using unhealthy weight control practices including random avoidance of staple foods, fasting, smoking and purging, in their pursuit of the 'perfect' female figure. Obesity prevention programmes which target adolescent girls 'at risk' of overweight and obesity, must take cognizance of their profound fear of fatness, otherwise the use of harmful slimming strategies may be further increased as teenage girls frantically try to lose weight and to avoid the stigma associated with female fatness.
Fasting gall bladder volume and lithogenicity in relation to glucose tolerance, total and intra-abdominal fat masses in obese non-diabetic subjects.
Hendel HW. Hojgaard L. Andersen T. Pedersen BH. Paloheimo LI. Rehfeld JF. Gotfredsen A. Rasmussen MH.
Department of Clinical Physiology, Hvidovre Hospital, Copenhagen, Denmark.
OBJECTIVE: To investigate whether total body fat mass or fat distribution and associated metabolic disturbances in glucose and lipid metabolism influence the well known gallstone pathogenetic factors in obese subjects in order to explain why some obese subjects develop gallstones and some do not. DESIGN: Cross sectional study of gallstone pathogenetic factors, body composition, fat distribution, glucose and lipid metabolism. SUBJECTS: 57 healthy overweight subjects (aged 26-64y, body mass index (BMI) 30-45 kg/m2). MEASUREMENTS: Total and intra-abdominal fat masses were measured by dual X-ray absorptiometry and abdominal CT scanning, respectively. The lithogenic index was measured in aspirated bile. The gallbladder volume was determined by ultrasound and the gallbladder ejection fraction% by dynamic cholescintigraphy. Plasma cholecystokinin (CCK) concentrations during a meal were measured with a specific radioimmunoassay. Insulin sensitivity was measured by the Minimal Model and glucose tolerance by an oral glucose tolerance test (OGTT). Serum lipid concentrations were measured by standard methods. RESULTS: The gallbladder volume in the fasting state increased with increasing intra-abdominal fat mass (P=0.006) and was increased in subjects with impaired glucose tolerance (41 vs 27 ml, P=0.001). The lithogenic index was > 1 in all subjects and correlated with total fat mass (P=0.04). CONCLUSION: Gallstone pathogenesis in obesity seems to be influenced by the total body fat mass and its regional distribution possibly via mutual association with the glucose tolerance.