Glucose and HbA1c Mediate Obesity–Pancreatic Cancer Link, UK Biobank Study Finds

A large prospective study leveraging the UK Biobank (搜索)搜索该词条 cohort has provided novel quantitative evidence that hyperglycemia—measured through blood glucose查看药品详情 and glycated hemoglobin (HbA1c (搜索)搜索该靶点)—serves as a key mediator in the relationship between obesity and pancreatic cancer (搜索)搜索该疾病 risk. Published in the British Journal of Cancer, the analysis of 367,615 participants followed for a median of 10.9 years identified glucose and HbA1c as significant intermediaries, with overall proportions mediated reaching 15.9% and 20.0%, respectively, for body mass index (BMI).

The findings reinforce the critical role of glycemic dysregulation in obesity-driven pancreatic carcinogenesis and point toward glycemic control as a potential target for risk reduction strategies.

Anthropometric traits and cancer risk

Using Cox proportional hazards regression, the researchers estimated associations between individual anthropometric traits and pancreatic cancer (搜索)搜索该疾病 incidence. Each one-standard-deviation (SD) increment in BMI (4.69 kg/m²), waist-to-hip ratio (WHR; 0.09), waist circumference (WC; 12.4 cm), and hip circumference (HC; 8.99 cm) was linked to a 20% (HR = 1.20; 95% CI: 1.12–1.28), 24% (HR = 1.24; CI: 1.14–1.36), 25% (HR = 1.25; CI: 1.16–1.35), and 16% (HR = 1.16; CI: 1.08–1.24) higher risk of pancreatic cancer, respectively.

When comparing extreme quartiles, participants in the highest quartile of WHR had a 68% increased risk (HR = 1.68; CI: 1.30–2.17) relative to the lowest quartile, while the highest BMI quartile showed a 54% elevated risk (HR = 1.54; CI: 1.25–1.88).

Body shape phenotypes through principal component analysis

To capture the complex interplay of multiple anthropometric traits, the team applied principal component analysis (PCA) to six standardized anthropometric measures. Three principal components (PCs) explained 98% of total variance. PC1, accounting for 66.20% of variance, distinguished individuals with general obesity from lean body shapes and was associated with a 20% higher pancreatic cancer (搜索)搜索该疾病 risk per one-SD increase (HR = 1.20; CI: 1.12–1.28). PC2 (tall with low WHR versus short with high WHR) and PC3 (tall with high WHR versus short with low WHR) showed no significant associations in the overall population.

Four-way decomposition mediation analysis

The study employed four-way decomposition mediation analysis to disentangle direct and indirect pathways, decomposing the total effect into controlled direct effect, reference interaction, mediated interaction, and pure indirect effect (PIE).

For BMI, significant mediation was observed through glucose查看药品详情, with an overall proportion mediated of 15.9% (CI: 2.8% to 28.9%), primarily driven by a PIE of 15.3% (CI: 1.4% to 29.3%). HbA1c (搜索)搜索该靶点 showed an overall proportion mediated of 20.0% (CI: 6.3% to 33.7%), with a PIE of 20.7% (CI: 5.5% to 36.0%).

Comparable mediation patterns emerged for WHR and WC. For WHR, overall proportions mediated were 12.0% (P = 0.007) for glucose查看药品详情 and 19.1% (P = 0.001) for HbA1c (搜索)搜索该靶点. For WC, the corresponding figures were 13.3% (P = 0.004) and 19.1% (P < 0.001).

For the general obesity body shape (PC1), significant PIEs were observed for glucose查看药品详情 (10.8%, CI: 1.8% to 19.8%) and HbA1c (搜索)搜索该靶点 (14.7%, CI: 4.8% to 24.7%), with overall proportions mediated of 12.2% (CI: 3.4% to 21.0%) and 15.0% (CI: 5.7% to 24.2%), respectively.

Additional mediators in sensitivity analyses

In single-biomarker sensitivity analyses without mutual adjustment, urate查看药品详情 and gamma-glutamyltransferase (搜索)搜索该靶点 emerged as additional potential mediators. Urate showed an overall proportion mediated of 21.9% (P = 0.017) in the BMI model and 23.0% (P = 0.014) in the PC1 model. Gamma-glutamyltransferase demonstrated overall proportions mediated of 19.6% (P = 0.005) for BMI and 16.2% (P = 0.004) for PC1. However, these biomarkers did not retain statistical significance in mutually adjusted models, suggesting their mediating effects may be influenced by other metabolic pathways.

Study design and population

The analysis drew on 462,300 UK Biobank (搜索)搜索该词条 participants after excluding those with prevalent cancer or missing anthropometric data, with 367,615 included in the complete-case analytic sample. Over follow-up, 1,115 incident pancreatic cancer (搜索)搜索该疾病 cases were ascertained through cancer registries and national health databases. The average age at recruitment was 56.8 ± 8.1 years.

Biomarkers were measured from non-fasting baseline blood samples and included markers of glucose查看药品详情 metabolism (glucose, HbA1c (搜索)搜索该靶点), insulin signaling (IGF-1), inflammation (C-reactive protein), sex hormones, lipid metabolism, and liver function. Notably, IGF-1 showed no significant association with pancreatic cancer (搜索)搜索该疾病 risk (HR = 1.01; 95% CI: 0.94–1.09) and was therefore excluded from primary mediation analyses.

Clinical and public health implications

The authors note that these findings "highlight the role of obesity-related metabolic dysfunction in pancreatic carcinogenesis and underscore the importance of glycemic control as a potential target for risk reduction." The consistency of mediation effects across individual anthropometric measures and composite body shape phenotypes reinforces the centrality of glucose查看药品详情 dysregulation in obesity-associated pancreatic cancer (搜索)搜索该疾病.

The study acknowledges several limitations, including its observational design, non-fasting blood sample collection, and limited generalizability. The cross-sectional nature of the mediation analysis also restricts causal interpretation of mediator-outcome relationships. Nonetheless, the use of four-way decomposition represents a methodological advance over traditional mediation approaches by simultaneously quantifying both mediation and interaction effects.

"Future research should aim to identify additional biological pathways involved in this relationship to further elucidate mechanisms," the researchers conclude.