Total polyunsaturated fatty acid intake and the risk of non-alcoholic fatty liver disease in Chinese Han adults: a secondary analysis based on a case–control study

Background Previous studies have revealed obesity, nutrition, lifestyle, genetic and epigenetic factors may be risk factors for the occurrence and development of non-alcoholic fatty liver disease (NAFLD). However, the effect of total polyunsaturated fatty acid (PUFA) consumption on the risk of NAFLD is uncertain. Therefore, this study aimed to determine whether the total PUFA intake is independently associated with the risk of NAFLD and explore the threshold of PUFA intake better illustrate the correlation between them in Chinese Han adults. Methods The present study was a retrospective case–control study. A total of 534 NAFLD patients and 534 controls matched by gender and age in the same center were included in this study. Using a semi-quantitative food frequency questionnaire in a health examination center in China to collect information about dietary intake and calculate nutrient consumption. A multivariate logistic regression model was used to estimate the association between total PUFA daily intake and its quartile and the incidence of NAFLD. Results Multivariate analyses suggested a significant association between total PUFA intake and the occurrence of NAFLD. A non-linear relationship between total PUFA consumption and NAFLD risk was detected after adjusting for potential confounding factors. There was a significant connection between PUFA and the risk of NAFLD (OR: 1.32, 95% CI: 1.23–1.41, P < 0.0001) when PUFA intake is between 18.8 and 29.3 g/day. Conclusions The relationship between total PUFA intake and NAFLD is non-linear. Total PUFA was positively related to the risk of NAFLD when PUFA intake is between 18.8 and 29.3 g/day among Chinese Han adults.

Normal reference intervals of prognostic nutritional index in healthy adults: A large multi-center observational study from Western China

Background It has been widely reported that the prognostic nutritional index (PNI) played a pivotal role in nutritional assessment of surgical patients and tumor prognosis. In order to improve the accuracy of evaluation in western China, we established reference intervals (RIs) of PNI in healthy controls. Methods A retrospective cohort study on healthy ethnic Han adults (18–79 years) was conducted to explore the influences of age, gender, study centers, and instruments on PNI and to establish RIs. The data came from a healthy routine examination center database and laboratory information system (LIS) of four centers in western China, and there were 200 persons selected randomly for verification of RIs. Results 5,839 healthy candidates were enrolled. PNI showed a marked gender dependence, and males had significantly higher PNI than females across all ages (P < 0.01). We found that PNI is significantly different between age groups (P < 0.01), the value of PNI tended to decrease with age increasing. There is also an obvious influence of centers and instruments on PNI (P < 0.01). Conclusions We established reference intervals of PNI in healthy Han Chinese population in Western China, and validated successfully. Further established RIs will lead to better standardizations of PNI for clinical applications.