Association between dietary inflammatory index and the risk of oral cancer in the southeast of China

Dietary patterns and risk of oral and oropharyngeal cancers: A systematic review and meta-analysis

Systematic evaluation of evidence assessing the role of dietary patterns on oral and oropharyngeal (OOP) cancer risk can provide a better understanding of their relationship. This systematic review of observational studies aimed to integrate the most recent evidence on the relationship between posteriori and priori dietary patterns and risk of development of OOP cancers. Studies were retrieved from Embase, PubMed, and Web of Science, and a total of 22 publications were included in the systematic review, of which 17 were included in the meta-analysis. Summary risk was estimated for highest versus lowest intakes of most common identified food groups and risk of OOP cancers using the random effect, generic inverse variance method. The quality of the included studies was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS) for Case-Control and Cohort studies. As per pooled analysis, consumption of healthy patterns may decrease the risk of OOP cancers by 43 %, and that of western patterns may increase this risk by 62 %. The pooling of data from ten studies analysing priori patterns and OOP cancers shows that the Mediterranean diet and diverse diet reduce the risk of such cancers, and a pro-inflammatory diet escalates the risk. On NOS, 11 studies were good in quality and 11 were moderate. Adopting a diet rich in fruits and vegetables and low intake of snacks and animal fats can potentially reduce the likelihood of developing OOP cancers. Encouraging Mediterranean diet, diverse diet and anti-inflammatory food components would be beneficial in the prevention and control of OOP cancers.

Dietary Inflammatory Index, Obesity, and the Incidence of Colorectal Cancer: Findings from a Hospital-Based Case-Control Study in Malaysia

Obesity-mediated inflammation represents a key connection between the intake of foods with high inflammatory potential and colorectal cancer (CRC) risk. We aimed to explore the association between energy-adjusted dietary inflammatory index (E-DII) in relation to CRC risk in both obese and non-obese subjects. This study included 99 histopathologically confirmed CRC cases, 73 colonic polyps cases, and 141 healthy controls from tertiary medical centres in both urban and suburban areas in Peninsular Malaysia. The subjects were categorised into body mass index (BMI) < 25 kg/m² and BMI ≥ 25 kg/m² groups. E-DII scores were computed based on dietary intake assessed using a validated food frequency questionnaire (FFQ). Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential cofounders. The mean dietary energy intake and mean BMI values of the subjects tended to increase as the E-DII scores increased (p for trend < 0.001). E-DII was significantly related to CRC risk only in obese subjects (OR = 1.45; 95% CI = 1.30-1.77; p < 0.001 for trend). Stratified analyses of risk factors showed significant associations between E-DII and CRC risk by age group (p for interaction = 0.030), smoking status (p for interaction = 0.043), and anthropometric indices for both males and females (p for interaction < 0.001) in the most pro-inflammatory E-DII quartile vs. the lowest E-DII quartile. Overall, pro-inflammatory diets were associated with an increased incidence of CRC in the Malaysian population, particularly in obese subjects.

Modifiable risk factors for oral cavity cancer in non-smokers: A systematic review and meta-analysis

BACKGROUND

Oral cavity cancer (OCC) is traditionally associated with smoking, but there is an increasing prevalence of the disease among non-smokers. This review investigates possible modifiable risk factors in the development of OCC in non-smokers (OCCNS).

METHODS

PubMed, EMBASE, Web of Science, and Scopus were searched for publications prior to June 2021. Comparative studies investigating modifiable OCCNS risk factors were identified following PRISMA guidelines. Publication date, population size, and results were indexed. Study quality was assessed using MINORS (Methodological Index for Non-Randomized Studies). Factors examined by multiple studies were analyzed using random-effect meta-analysis framework.

RESULTS

Literature search resulted in 1,625 unique publications. 52 records met inclusion criterion, investigating alcohol (n = 22), chewing products (n = 18), diet (n = 7), dental health (n = 11), and medical comorbidities (n = 6).

CONCLUSION

This review demonstrates the paucity of large studies investigating OCCNS risk factors. Further investigation is warranted to help clinicians risk-stratify patients without traditional risk factors.

Association between dietary inflammatory index and oral cancer risk: A systematic review and dose–response meta-analysis

Background

Dietary inflammatory index (DII) has been suggested to be associated with oral cancer risk. However, a quantitative comprehensive assessment of the dose–response relationship has not been reported. We performed a meta-analysis to clarify the risk of oral cancer with DII.

Methods

We searched PubMed, Embase, Cochrane Library, and Web of Science databases for relevant articles published up to 1 March 2022. Fixed- or random-effects models were utilized to estimate the pooled odds ratio (OR) of oral cancer with DII, as appropriate. Restricted cubic splines were used to model the dose–response relationship.

Results

We included five case–control studies involving 1,278 cases and 5,137 controls in the meta-analysis. Risk of oral cancer was increased by 135% with the highest versus lowest DII level [OR: 2.35, 95% confidence interval (CI): 1.88–2.94], and 79% with higher versus lower DII level (OR: 1.79, 95% CI: 1.49–2.15). We found no evidence of a nonlinear dose–response association of DII with oral cancer (p_{non-linearity} = 0.752), and the risk was increased by 17% (OR: 1.17, 95% CI: 1.05–1.30) with 1 unit increment in DII score.

Conclusion

This meta-analysis suggested that a higher DII score was associated with increased risk of oral cancer. Therefore, reducing pro-inflammatory components and promoting anti-inflammatory components of diet may be effective in the prevention of oral cancer.