Trends in dietary fiber intake in Japan over the last century

Summary. Background: Insufficient intake of dietary fiber (DF) is currently a major problem in the overall promotion of health in the general population in Japan. Aim of the study: To analyze the time trends in DF intake, including DF density (total DF intake/1,000 kcal), and the ratio of water-insoluble fiber to water-soluble fiber (IS ratio) in Japan. Methods: The time trend in DF intake in Japan was calculated from data compiled in the Japanese National Nutrition Survey. Results: The mean daily DF intake (total DF intake) in 1952 was 20.5 g/day, which rapidly declined to about 70 % of the 1952 level in 1970, after which there was little change to 1998. DF density in 1952 was 9.7 g/1000 kcal, which declined by about 30 % in 1970, and remained at about the same level to 1998. The IS ratio has remained stable over this period. Whereas total DF intake and DF density in Japan are similar to those in Western countries, the IS ratios are higher in Japan. Therefore, the higher incidence of, and mortality from, colon diverticulosis, coronary heart disease, hyperlipidemia, etc., which are all thought to be related to fiber deficiency, in Western countries compared to Japan might be due to the differences in the IS ratio. Conclusions: A decline in total DF intake and DF density is predicted for Japan in the future, because these parameters were lower among the younger generation. This may be due to the marked changes in the dietary habits of the younger generation, and is a problematic trend for Japanese health. Received: 26 April 2002, Accepted: 22 August 2002 Correspondence to: Shigeyuki Nakaji, MD, PhD     

Dietary intake of total polyphenol and polyphenol classes and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and subclasses of polyphenols and CRC risk and its main subsites, colon and rectum, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The cohort included 476,160 men and women from 10 European countries. During a mean follow-up of 14 years, there were 5991 incident CRC cases, of which 3897 were in the colon and 2094 were in the rectum. Polyphenol intake was estimated using validated centre/country specific dietary questionnaires and the Phenol-Explorer database. In multivariable-adjusted Cox regression models, a doubling in total dietary polyphenol intake was not associated with CRC risk in women (HR_log2?=?1.06, 95% CI 0.99–1.14) or in men (HR_log2?=?0.97, 95% CI 0.90–1.05), respectively. Phenolic acid intake, highly correlated with coffee consumption, was inversely associated with colon cancer in men (HR_log2?=?0.91, 95% CI 0.85–0.97) and positively associated with rectal cancer in women (HR_log2?=?1.10, 95% CI 1.02–1.19); although associations did not exceed the Bonferroni threshold for significance. Intake of other polyphenol classes was not related to colorectal, colon or rectal cancer risks. Our study suggests a possible inverse association between phenolic acid intake and colon cancer risk in men and positive with rectal cancer risk in women.     

How Many Imputations are Really Needed? Some Practical Clarifications of Multiple Imputation Theory

Multiple imputation (MI) and full information maximum likelihood (FIML) are the two most common approaches to missing data analysis. In theory, MI and FIML are equivalent when identical models are tested using the same variables, and when m, the number of imputations performed with MI, approaches infinity. However, it is important to know how many imputations are necessary before MI and FIML are sufficiently equivalent in ways that are important to prevention scientists. MI theory suggests that small values of m, even on the order of three to five imputations, yield excellent results. Previous guidelines for sufficient m are based on relative efficiency, which involves the fraction of missing information (γ) for the parameter being estimated, and m. In the present study, we used a Monte Carlo simulation to test MI models across several scenarios in which γ and m were varied. Standard errors and p-values for the regression coefficient of interest varied as a function of m, but not at the same rate as relative efficiency. Most importantly, statistical power for small effect sizes diminished as m became smaller, and the rate of this power falloff was much greater than predicted by changes in relative efficiency. Based our findings, we recommend that researchers using MI should perform many more imputations than previously considered sufficient. These recommendations are based on γ, and take into consideration one’s tolerance for a preventable power falloff (compared to FIML) due to using too few imputations.     

Determinants of Birthweight; Gender Based Analysis

The objective of this cross sectional study is to look at determinants of birth weight and their association with the gender of the baby in 2,795 full term children living in the occupied Palestinian territory, derived from a stratified random sample of 2,994 households in the West Bank and 2,234 households in the Gaza Strip. The response rate was 85%. Multivariable analysis using analysis of variance for mixed models showed that sex and birth order, maternal age and education and to a lesser extent region were determinants of birth weight for all children. The effect of maternal education on birth weight differed for female and male infants, tending to be relatively unchanged for male infants and with mean birth weights increasing with maternal education in female infants. The effect of birth order differed by maternal age, with mean birth weight increasing with maternal age for first and second births; but being unaffected by maternal age for infants of birth order greater than two. We conclude that birth weight is influenced by common biological determinants across cultures, but is also influenced by social, ethnic, and environmental factors that are culture specific, of which some might be gender related.

Mit Kiffen aufhören. Die Bereitschaft zur Verhaltensänderung bei Cannabisgebrauchenden in der Schweiz

Summary Quitting hash. The readiness for behaviour change among cannabis users in Switzerland. Objectives: The study aims to identify factors that are associated with the willingness of adolescents and young adults to modify their cannabis use. It is hypothesized that frequency of use, cannabis-related problems and age of onset are associated with their willingness to change. Methods: In 2004, a survey on cannabis use was conducted among 13 to 29 year-olds living in Switzerland. Of the 5025 participants 593 had taken cannabis during the past six months. They were then asked about their willingness to change. Three groups of users were compared: those not willing to change, those considering change, and those determined to change. Pearson Chi-square-tests and logistic regressions were performed to test the hypotheses. Results: Experience of problems motivates users to start thinking about changing their behavior. Frequent use and early onset are associated with young people not making the transition from considering changing behavior to resolving to do so. Conclusions: The need to perceive problematic use as a first step towards change and the inhibiting effect of dependencerelated factors on the transition from consideration to determination calls for tailored intervention approaches that are matched to the willingness to change. Eingereicht: 10. Dezember 2005; überarbeitet: 13. September 2006; Angenommen: 6. M?rz 2007     

Significant accumulation of KRAS mutations in bronchiolar metaplasia-associated honeycomb lesions of interstitial pneumonia

Interstitial pneumonia (IP) is a major risk factor for lung adenocarcinoma (LADC). IP-related LADC predominantly develops in the bronchiolar metaplasia lining in honeycomb lesions. Kirsten rat sarcoma virus (KRAS) is the most common oncogene mutated in IP-related LADC. The present study examined the metaplastic epithelia in honeycomb lesions for KRAS mutations using digital droplet polymerase chain reaction (ddPCR), a sensitive method used to detect infrequent mutations. Significantly higher KRAS mutation variant allele frequencies (VAFs) were detected in the metaplastic lung epithelia from 13 patients with IP compared with those in 46 non-lesioned lung samples from patients without IP (G12V, P=0.0004, G12C, P=0.0181, and G12A, P=0.0234; Mann Whitney U test). Multivariate analyses revealed that higher KRAS G12V (logistic regression model; P=0.0133, odds ratio=7.11) and G12C (P=0.0191, odds ratio=5.81) VAFs in patients with IP were independent of confounding variables, such as smoking and age. In patients with IP, metaplastic epithelia exhibited significantly higher KRAS G12V and G12C VAFs compared with the non-lesioned counterparts (paired t-test; G12V, P=0.0158, G12C, P=0.0465). These results suggested that IP could increase KRAS mutations and supported the hypothesis that bronchiolar metaplasia could be a precursor for IP-related LADC.     

Validation of Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in patients scheduled for total knee replacement

Objective Our aim was to cross-culturally validate Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in patients with knee osteoarthritis (OA) scheduled for total knee replacement in Singapore. Methods Chinese WOMAC was translated from the original English version following standard guidelines. Patients were asked to complete a questionnaire containing the WOMAC (twice within 6 days), the Short Form 36 (SF-36), and the EuroQoL EQ-5D. Reliability was assessed using Cronbach’s alpha and intraclass correlation coefficients (ICC), dimensionality using item-to-domain correlations and factor analyses. Convergent and discriminant construct validity was assessed using six each a priori hypotheses. Results Chinese WOMAC was well accepted by the patients in the pilot test. The Chinese and English versions were therefore administered to a consecutive sample of 131 Chinese- and 127 English-speaking subjects, respectively, with knee OA. Cronbach’s alpha exceeded 0.7 for all domains except for Chinese pain domain, whereas the ICC exceeded 0.7 for all domains. Hypothesized item-to-domain correlations were observed for all items except for four items in Chinese physical function domain. The factor analyses yielded seven and five factors with eigenvalues of more than 1.0 in the Chinese and English versions, respectively. A total of 10/12 a priori construct validity hypotheses were satisfied for the Chinese version. Weak correlations between WOMAC pain and SF-36 bodily pain and moderate correlation between WOMAC pain and EQ-5D anxiety/depression were observed. Conclusions Chinese WOMAC was well accepted and demonstrated acceptable psychometric properties in Singaporean patients with severe knee OA.     

Effect of an EBM course in combination with case method learning sessions: an RCT on professional performance,job satisfaction,and self-efficacy of occupational physicians

OBJECTIVE: An intervention existing of an evidence-based medicine (EBM) course in combination with case method learning sessions (CMLSs) was designed to enhance the professional performance, self-efficacy and job satisfaction of occupational physicians. METHODS: A cluster randomized controlled trial was set up and data were collected through questionnaires at baseline (T0), directly after the intervention (T1) and 7 months after baseline (T2). The data of the intervention group [T0 (n = 49), T1 (n = 31), T2 (n = 29)] and control group [T0 (n = 49), T1 (n = 28), T2 (n = 28)] were analysed in mixed model analyses. Mean scores of the perceived value of the CMLS were calculated in the intervention group. RESULTS: The overall effect of the intervention over time comparing the intervention with the control group was statistically significant for professional performance (p < 0.001). Job satisfaction and self-efficacy changes were small and not statistically significant between the groups. The perceived value of the CMLS to gain new insights and to improve the quality of their performance increased with the number of sessions followed. CONCLUSION: An EBM course in combination with case method learning sessions is perceived as valuable and offers evidence to enhance the professional performance of occupational physicians. However, it does not seem to influence their self-efficacy and job satisfaction.