Abstract 2199: Low-carbohydrate diet score and risk of bladder cancer: Findings from the Singapore Chinese Health Study
Authors: Pham Yen Thi-Hai , Wang Renwei , Jin Aizhen , Koh Woon-Puay , Yuan Jian-Min , Luu Hung N. 
Published: March 2024

Background. Bladder cancer is a leading tumor of urinary tract with annually 570,000+ new cases and 200,000+ deaths worldwide. In the United States, the current incidence rate of bladder cancer is 15.8 per 100,000 population with more than 82,000 new cases and more than 16,000 deaths each year. Although smoking is established as a major risk factor for bladder cancer development, accounting for 30-50% cases, the role of other modifiable risk factors, including dietary in bladder cancer remains unclear. Low-carbohydrate diet (LCD) is a dietary pattern to restrict carbohydrate and to favor protein and/or fat intakes that has recently been well-accepted for weight loss. While its short-term effect to support the weight loss has been popular, its long-term effect on chronic diseases, including cancer, needs to be elucidated. In the current analysis, we sought to determine the association between LCD scores and bladder cancer risk in the Singapore Chinese Health Study (SCHS), an ongoing prospective cohort study consisting of more than 63,000 Chinese Singaporeans, 45- 74 years of age at baseline enrollment period 1995-1998.

Methods. Total, animal-based and plant-based LCD scores were derived from the baseline dietary survey data, representing summed intake of carbohydrates, fats and proteins from all dietary, animal- and plant-food sources, respectively. Bladder cancer cases were ascertained using cancer registry. Cox proportional hazard regression model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for different LCD score levels with risk of bladder cancer.

Results. By December 31, 2015, or after 17.6 years of follow-up, 250 bladder cancer cases were developed within the SCHS. Total LCD score was marginally associated with increased risk of bladder cancer (HRQ4vs.Q1=1.43, 95% CI: 0.98-2.09, Ptrend = 0.06). Animal-based LCD score was significantly associated with risk of bladder cancer. The HRs and respective 95% CIs of bladder cancer for quartiles 2, 3, and 4, compared with the lowest quartile, were 1.09 (0.76-1.56), 1.17 (0.81-1.70), and 1.53 (1.09-2.17) (Ptrend=0.01). The positive association was only present in men, ever smokers, never drinkers and individuals without history of type 2 diabetes (All P’sheterogeneity&gt;0.05).

Conclusions. In a prospective cohort study of more than 63,000 Chinese Singaporeans, we found that animal-based LCD score, representing a diet with lower carbohydrate and higher animal fat and protein, was significantly associated with increased risk of bladder cancer. Dietary modification is therefore suggested as an effective strategy for primary prevention of bladder cancer.

Citation Format: Yen Thi-Hai Pham, Renwei Wang, Aizhen Jin, Woon-Puay Koh, Jian-Min Yuan, Hung N. Luu. Low-carbohydrate diet score and risk of bladder cancer: Findings from the Singapore Chinese Health Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2199.