Nutrient Patterns and Bladder Cancer: A Case-Control Study in Iran

To examine the association between nutrient patterns (NP) and the risk of bladder cancer (BC) in the Iranian population, this Hospital-based case-control study was conducted with 306 participants (106 cases and 200 controls). The cases were newly diagnosed with BC (transitional cell carcinoma). Participants' past year's dietary intake was obtained via a valid 168-item Food Frequency Questionnaire (FFQ). Principal Component Analysis was applied to derive NPs considering the intake of the nutrients. Logistic regression models were used to estimate the odds ratio (ORs) and 95%CIs. Two main NPs were obtained - Mineral Dominant (NP1) and Fat Dominant (NP2). NP1 was characterized by a high loading of folate, total carbohydrate, iron, phosphorus, fiber, total protein, magnesium, potassium, and calcium. NP2 had high loadings of trans-fatty acid (TFA), poly-unsaturated fatty acid (PUFA), total fat, saturated fatty acid (SFA), sodium, and cholesterol. Higher adherence to NP1 pattern significantly decreased the odds of BC (OR = 0.24, 95%CI: 0.09-0.67). In contrast, high adherence to NP2 resulted in almost a five-fold increase in the odds of BC (OR = 5.41, 95%CI: 2.26, 12.95). Variability in nutrient patterns has significant associations with the risk of BC, further highlighting the need to study patterns of nutrient intake rather than single nutrients.