Association Between Metabolic Syndrome and Its Components and the Risk of Head and Neck Cancer: A Systematic Review...

The relationship between metabolic syndrome (MetS) and head and neck cancer (HNC) remains controversial. The present meta-analysis evaluated the association between MetS and the risk of developing HNC.

A literature search was conducted across various databases, including Embase, Cochrane, PubMed, and Web of Science, to identify studies investigating the relationship between MetS and the risk of HNC.

Twelve studies involving 55,692 participants were included. We found limited evidence of an association between MetS and the risk of developing HNC (RR = 1.1, 95% CI: 1.0-1.2, p = 0.07, I² = 94%). Similar results were observed for HNC subtypes. Components of MetS revealed that underweight (BMI < 18.5 kg/m²) was associated with an increased risk of HNC (RR = 1.7, 95% CI: 1.5-1.9, p < 0.001). Low high-density lipoprotein (HDL) cholesterol levels (RR = 1.0, 95% CI: 1.0-1.1, p = 0.003), hypertension (RR = 1.1, 95% CI: 1.0-1.1, p = 0.007), and diabetes (RR = 1.1, 95% CI: 1.0-1.2, p = 0.001) were associated with a minimal increase in the risk of HNC. However, high low-density lipoproteins (LDL) cholesterol levels (RR = 0.8, 95% CI: 0.7-0.9, p < 0.001) and high total cholesterol levels (RR = 0.9, 95% CI: 0.9-0.9; p < 0.001) were associated with a reduced risk of HNC. Additionally, an increasing number of MetS components was associated with a higher risk of HNC.

In conclusion, our meta-analysis found little evidence of an association between MetS and the risk of developing HNC. However, high LDL and total cholesterol levels may be associated with a reduced risk of HNC, while being underweight may be associated with increased risk of HNC. These results need to be interpreted with caution due to the limited number of supporting studies.