Lower skeletal muscle attenuation and high visceral fat index are associated with complicated disease in patients with Crohn's disease: An exploratory study.

BACKGROUND AND AIMS: The prognostic value of body composition analysis in patients with Crohn's disease (CD) is poorly explored. The aims of the present study were to assess fat and skeletal muscle compartments including muscle radiation attenuation (MA) in patients with CD, and to analyze its predictive value to identify complicated phenotypes. METHODS: Seventy one patients with CD who have had an abdominal CT within one month of clinical, laboratory, and endoscopic evaluation were included. Skeletal muscle area (SMA) and index (SMI), visceral fat area (VFA) and index (VFI), subcutaneous fat area (SFA), and mean MA were measured using appropriate software. Sarcopenia, as defined by Martin's criteria was assessed. Montreal classification was used to characterize disease phenotype. RESULTS: Mean MA was lower in patients >40 years (p = 0.001), L2 (p = 0.09) and stricturing/penetrating disease (p = 0.03) whereas SMA and SMI were significantly lower in patients with positive C-reactive protein and previous hospital admissions (p < 0.01). On multivariate analysis, higher MA was protective against the complicated disease phenotype (stricturing/penetrating disease and/or previous surgeries) (OR 0.81; p = 0.002) whereas a high visceral fat index increased such risk (OR 26.1; p = 0.02). A ROC curve showed a 82.4% sensibility, 90.3% specificity, 17.6% positive predictive value, 9.7% negative predictive value and an area under the curve (AUC) of 0.91 for body composition analysis to predict complicated disease. CONCLUSIONS: A lower muscle attenuation and a high visceral fat index seem to be associated with more severe phenotypes in patients with CD.

IL23R polymorphisms influence phenotype and response to therapy in patients with ulcerative colitis.

OBJECTIVE: We aimed to identify the clinical and genetic [IL23 receptor (IL23R) single nucleotide polymorphisms (SNPs)] predictors of response to therapy in patients with ulcerative colitis. PATIENTS AND METHODS: A total of 174 patients with ulcerative colitis, 99 women and 75 men, were included. The mean age of the patients was 47±15 years and the mean disease duration was 11±9 years. The number of patients classified as responders (R) or nonresponders (NR) to several therapies was as follows: 110 R and 53 NR to mesalazine (5-ASA), 28 R and 20 NR to azathioprine (AZT), 18 R and 7 NR to infliximab. Clinical and demographic variables were recorded. A total of four SNPs were studied: IL23R G1142A, C2370A, G43045A, and G9T. Genotyping was performed by real-time PCR using Taqman probes. RESULTS: Older patients were more prone to respond to 5-ASA (P=0.004), whereas those with pancolitis were less likely to respond to such therapies (P=0.002). Patients with extraintestinal manifestations (EIMs) were less likely to respond to 5-ASA (P=0.001), AZT (P=0.03), and corticosteroids (P=0.06). Carriers of the mutant allele for IL23R SNPs had a significantly higher probability of developing EIMs (P<0.05), a higher probability of being refractory to 5-ASA (P<0.03), but a higher likelihood of responding to AZT (P=0.05). A significant synergism was observed between IL23R C2370A and EIMs with respect to nonresponse to 5-ASA (P=0.03). CONCLUSION: Besides extent of disease and age at disease onset, the presence of EIMs may be a marker of refractoriness to 5-ASA, corticosteroids, and AZT. IL23R SNPs are associated both with EIMs and with nonresponse to 5-ASA and corticosteroids.

The D1822V APC polymorphism interacts with fat, calcium, and fiber intakes in modulating the risk of colorectal cancer in Portuguese persons.

BACKGROUND: Both genetic and environmental factors affect the risk of colorectal cancer (CRC). OBJECTIVE: We aimed to examine the interaction between the D1822V polymorphism of the APC gene and dietary intake in persons with CRC. DESIGN: Persons with CRC (n = 196) and 200 healthy volunteers, matched for age and sex in a case-control study, were evaluated with respect to nutritional status and lifestyle factors and for the D1822V polymorphism. RESULTS: No significant differences were observed in energy and macronutrient intakes. Cases had significantly (P < 0.05) lower intakes of carotenes, vitamins C and E, folate, and calcium than did controls. Fiber intake was significantly (P = 0.004) lower in cases than in controls, whereas alcohol consumption was associated with a 2-fold risk of CRC. In addition, cases were significantly (P = 0.001) more likely than were controls to be sedentary. The homozygous variant for the APC gene (VV) was found in 4.6% of cases and in 3.5% of controls. Examination of the potential interactions between diet and genotype found that a high cholesterol intake was associated with a greater risk of colorectal cancer only in noncarriers (DD) of the D1822V APC allele (odds ratio: 1.66; 95% CI: 1.00, 2.76). In contrast, high fiber and calcium intakes were more markedly associated with a lower risk of CRC in patients carrying the polymorphic allele (DV/VV) (odds ratio: 0.50; 95% CI: 0.27, 0.94 for fiber; odds ratio: 0.51; 95% CI: 0.28, 0.93 for calcium) than in those without that allele. CONCLUSION: These results suggest a significant interaction between the D1822V polymorphism and the dietary intakes of cholesterol, calcium, and fiber for CRC risk.

Association of colonic and endometrial carcinomas in Portuguese families with hereditary nonpolyposis colorectal carcinoma significantly increases the probability of detecting a pathogenic mutation in mismatch repair genes, primarily the MSH2 gene.

BACKGROUND: Hereditary nonpolyposis colorectal carcinoma (HNPCC) significantly raises the risk of developing colorectal carcinoma (CRC) and other extracolonic tumors. It is defined by the Amsterdam Criteria and is associated with germline mutations in mismatch repair genes, primarily MLH1 and MSH2. The objectives of the current study were to evaluate the presence of CRC (Type I) and other extracolonic tumors (Type II) in families with HNPCC and to analyze the findings for correlations with germline mutations in the MLH1 and MSH2 genes. METHODS: Seventy families with an HNPCC diagnosis were analyzed. Denaturing gradient gel electrophoresis and direct sequencing were used for germline mutation analysis in the MLH1 and MSH2 genes. RESULTS: Forty-three of 70 families (61%) presented with HNPCC Type II. In 21 of 30 families that had a complete genetic diagnosis, 16 pathogenic germline mutations (7 MLH1 mutations and 9 MSH2 mutations) and 5 mutations of unknown pathogenecity (all MLH1 mutations) were found. In the remaining nine families, no mutations were detected. Unequivocally pathogenic mutations were far more common in families with HNPCC Type II compared with families that had CRC only (P = 0.01). Families with endometrial carcinoma presented with the greatest probability of mutational detection (P = 0.005). MLH1 was only gene affected in families with HNPCC Type I, whereas mutations in both MLH1 and MSH2 were found in families with HNPCC Type II (P = 0.04). However, the MSH2 gene was more frequently involved in families with HNPCC in which endometrial carcinoma was present (P = 0.005). CONCLUSIONS: CRC and endometrial carcinoma were associated with a greater probability of detecting pathogenic mutations in mismatch repair genes, with MSH2 involvement predominating. The results support specific mutational screening strategies, based on observed phenotypes, for families with HNPCC.