We aimed to investigate the association between plasma retinol and incident cancer among Chinese hypertensive adults.Methods:
We conducted a nested case-control study, including 231 patients with incident cancer and 231 matched controls during a median 4.5-year follow-up of the China Stroke Primary Prevention TrialResults:
There was a significant, inverse association between retinol levels and digestive system cancer (per 10 μg/dL increase: RR, 0.79; 95%CI: 0.69–0.91). When compared with participants in the first quartile of retinol (<52.3 μg/dL), a significantly lower cancer risk was found in participants in quartile 2–4 (≥52.3 μg/dL: RR, 0.31; 95%CI: 0.13–0.71). However, there was a U-shaped association between retinol levels and non-digestive system cancers where the risk of cancers decreased (although not significantly) with each increment of plasma retinol (per 10 μg/dL increase: RR, 0.89; 95%CI: 0.60–1.31) in participants with retinol < 68.2 μg/dL, and then increased significantly with retinol (per 10 μg/dL increase: RR, 1.65; 95%CI: 1.12–2.44) in participants with retinol ≥68.2 μg/dL.Conclusion:
There was a significant inverse dose-response association between plasma retinol and the risk of digestive system cancers. However, a “U” shaped association was observed between plasma retinol and the risk of non-digestive cancers (with a turning point around 68.2 μg/dL).