Low-fat dairy consumption and the risk of lung cancer: A large prospective cohort study.

BACKGROUND: Despite the possible contribution of dairy products to the development or prevention of cancers, there is a lack of epidemiological evidence linking low-fat dairy consumption to the risk of developing lung cancer. This research was conducted to fill this knowledge gap. METHODS: The data for this research were collected from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. The Cox proportional risk model was employed to evaluate the link between low-fat dairy consumption and the risk of developing lung cancer. Hazard ratios (HRs) and 95% confidence intervals (CIs) were measured in both unadjusted and adjusted models. A series of predefined subgroup analyses were performed to identify potential effect modifiers, and several sensitivity analyses were conducted to assess the stability of the findings. RESULTS: The study included data from 98,459 individuals. During a total of 869,807.9 follow-up person-years, 1642 cases of lung cancer were observed, with an incidence of 0.189 cases for every 100 person-years. In the fully adjusted model, participants in the highest quartile of low-fat dairy consumption had a significantly decreased risk of lung cancer compared to the ones in the lowest quartile (HRquartile 4 vs. 1 : 0.769, 95% CI: 0.664, 0.891, ptrend = 0.005). The restricted cubic spline plot revealed an inverse nonlinear dose-response relationship between low-fat dairy consumption and lung cancer risk (pnonlinearity = 0.008). Subgroup analyses demonstrated that the inverse association was stronger among participants with higher daily caloric intake (pinteraction = 0.031). Various sensitivity analyses produced consistent results. CONCLUSION: Consuming more low-fat dairy products is significantly linked to a reduced risk of developing lung cancer, indicating that an appropriate increase in the use of low-fat dairy products may help prevent lung cancer.

Association between dietary approaches to stop hypertension eating pattern and lung cancer risk in 98,459 participants: results from a large prospective study.

Background: Dietary approaches to stop hypertension (DASH) eating pattern is linked to anti-inflammatory responses and antioxidation, which overlap with the pathogenesis of lung cancer. However, there is insufficient epidemiological evidence to link this dietary pattern to lung cancer risk conclusively. Aim: To determine if adherence to the DASH diet is linked to a lower risk of developing lung cancer in a large prospective study. Methodology: The data of participants were retrieved from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. A DASH score was calculated based on 8 dietary components to reflect adherence to DASH, with greater scores representing higher adherence. Three Cox proportional hazards models were constructed to analyze the association between DASH scores and lung cancer risk, including an unadjusted model and two adjusted models (model 1 for demographics and model 2 for fully confounding factors). A restricted cubic spline plot was utilized to illustrate the likelihood of developing lung cancer across the entire range of DASH scores. The association between each of the 8 DASH components and the risk of lung cancer was assessed separately. Several subgroup analyses were conducted to identify potential modifiers, and several sensitivity analyses were performed to verify the robustness of the findings. Results: The study involved 98,459 individuals in total. The mean (standard deviation) DASH score was 24.00 (4.62) points, along with the mean follow-up period of 8.84 (1.94) years. Lung cancer was identified in 1642 cases over 869807.9 person-years of follow-up, and the overall incidence rate was 0.189 cases/100 person-years. Participants in the highest quartile in the fully adjusted model had a relatively decreased risk of developing lung cancer in comparison to those in the lowest quartile (HRquartile 4 versus 1: 0.647; 95% CI: 0.557, 0.752; Ptrend < 0.001). The restricted cubic spline plot demonstrated that DASH score and lung cancer risk were inversely associated and had a linear dose-response relationship (Pnon-linear = 0.944). According to subgroup analyses, those who were current or former smokers had a stronger inverse connection than those who never smoked (Pinteraction = 0.013). The results remained robust after several sensitivity analyses. Conclusion: The risk of lung cancer was inversely associated with DASH scores in the US population. This suggests that following the DASH pattern can help prevent lung cancer, especially for current or former smokers. More epidemiological evidence from other regions and populations is needed to confirm our findings.

Association between soft drink consumption types and risk of lung cancer and all-cancer: A prospective study of PLCO data.

Diet/sugar-free soft drinks are considered to be healthier than regular soft drinks. However, few studies have examined the relationship between the types of soft drinks (regular and diet/sugar-free) and lung cancer (LC)/all-cancer (AC) risk. In this study, we comprehensively assessed the influence of the type of soft drink consumption on LC/AC risk based on the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Multivariable Cox proportional hazards and competing risks Fine-Gray regression models adjusted for relevant confounders were used to estimate hazard ratios (HRs) and subdistribution HRs for different types of soft drink consumption. In the PLCO population, female subgroup, and the ever/current smoker subgroup, consumption of both regular and diet soft drinks was associated with a significantly reduced risk of LC compared with no soft drinks at all. For the non-lung cancer (NLC) risk, consumption of only diet soft drinks had a significant positive association for the total population and female subgroup. Based on our findings, it was suggested that partial replacement of regular soft drinks with diet soft drinks might be beneficial to LC prevention, especially for females and ever/current smokers. Additionally, completely replacing regular soft drinks with diet soft drinks might be detrimental to NLC prevention, especially for females.

Role of dietary carbohydrates on risk of lung cancer.

OBJECTIVES: Inconsistent findings have been reported on the link between dietary carbohydrates and lung cancer. This study aims to comprehensively evaluate the role of dietary carbohydrates on lung cancer risk. MATERIALS AND METHODS: The prospective study is based on the PLCO trial, which recruited 113,096 eligible participants across the United States. Participants had to have completed baseline and diet history questionnaires. The incidence of lung cancer was acquired through self-report and medical record follow-up. A multivariable logistic model adjusted for confounders was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) of dietary carbohydrates, fiber, whole grains, glycemic index (GI) and glycemic load (GL) for lung cancer. Similar methods were applied in analyzing the carbohydrates and fiber from different food sources. Multinomial logistic models were used for sensitivity analysis with lung cancer subtypes as outcomes. RESULTS: Dietary carbohydrates and GL were inversely associated with lung cancer incidence in the PLCO population. Among various carbohydrates, 30-g daily consumption of dietary fiber was related to a lower risk of lung cancer (fourth vs first quartile OR: 0.62, 95 % CI: 0.54-0.72) compared with 8.8-g. Furthermore, consuming whole grains 2.3 servings per day as opposed to 0.3 servings per day was associated with a lower risk of lung cancer (OR: 0.73, 95 % CI: 0.64-0.83). A higher risk of lung cancer was seen for the consumption of high-GI food (OR: 1.19, 95 % CI: 1.05-1.35) and refined carbohydrates from soft drinks (OR: 1.23, 95 % CI: 1.04-1.46). CONCLUSION: Carbohydrates and fiber from fruits, vegetables and whole grains are associated with lower lung cancer risk. Refined carbohydrates from processed food, such as soft drinks, appear to increase risk.

Lung cancer incidence and mortality in relationship to hormone replacement therapy use among women participating in the PLCO trial: a post hoc analysis.

OBJECTIVE: To evaluate the impact of hormone replacement therapy (HRT) on the incidence and mortality of lung cancer among female participants in the prostate, lung, colorectal, and ovary (PLCO) trial. METHODS: All women participating in the PLCO trial with complete information about HRT exposure were included in the current analysis. All study population were aged 55-74 years without prior history of lung cancer at the time of study enrollment. Multivariate Cox regression analysis was used to evaluate the impact of HRT exposure on lung cancer incidence and mortality. For both end points, the model was adjusted for: age, body mass index, study arm, race, cigarette smoking and family history of lung cancer. RESULTS: A total of 77,911 female participants were included in the current analysis, including 27,663 participants who never used HRT before inclusion into the PLCO trial and 50,248 participants who used some form of HRT before inclusion into the PLCO trial. Prior exposure to HRT seems to be protective against the development of lung cancer in a multivariate analysis (hazard ratio for ever exposure versus never exposure 0.876; 95% CI 0.783-0.981; P = 0.022). Similarly, prior exposure to HRT seems also to be protective against death from lung cancer in a multivariate analysis (hazard ratio for ever exposure versus never exposure 0.814; 0.709-0.934; P = 0.003). Further multivariate Cox regression analysis showed that current HRT usage at the time of PLCO trial entry (and not former HRT usage) seemed to be protective against lung cancer development (hazard ratio for current versus never users 0.842; 0.743-0.954; P = 0.007) and lung cancer-specific mortality (hazard ratio for current versus never users 0.800; 0.686-0.932; P = 0.004). CONCLUSION: HRT use at the time of PLCO trial entry seems to be associated with lower probability of lung cancer development and death. Further studies are needed to elucidate the biological mechanisms behind this observation.

Lethal Prostate Cancer in the PLCO Cancer Screening Trial.

The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial randomized men to usual care or annual prostate-specific antigen (PSA) screening for 6 yr and digital rectal examination for 4 yr. This trial found no difference between the intervention and usual care arms of the study in the primary end point of prostate cancer (PCa)-specific mortality. The PLCO trial results have had a major impact on health policy and the rate of PSA screening in the United States. We analyzed the 13-yr screening and outcomes data from the 151 participants who died of PCa in the screening arm of the trial to better understand how randomization to screening failed to prevent PCa death in these men. We found that of these men, 81 (53.6%) either were never screened as part of the trial or had an initial positive screen. Only 17 (11.3%) of those who died reached year 6 of the trial with a PSA <4.0 ng/ml. The men who died in the screening arm were also older at study entry than the average PLCO participant (66 vs 62 yr; p < 0.001). Our analysis should inform the interpretation of the PLCO trial and provide insight into future trial design.