Current Smoking Dose-Dependently Associated with Decreased β-Cell Function in Chinese Men without Diabetes

Area of Science:

• Endocrinology
• Metabolic Health
• Public Health

Background:

• Chronic smoking is a global health concern.
• Understanding its metabolic effects, particularly on glucose regulation, is crucial.
• Previous research on smoking's impact on insulin resistance and beta-cell function is inconsistent.

Purpose of the Study:

• To investigate the association between chronic smoking and insulin resistance (IR) and beta-cell function in Chinese men without diabetes.
• To determine if smoking intensity correlates with impaired glucose metabolism markers.
• To provide insights into the mechanisms linking smoking to metabolic dysfunction.

Main Methods:

• A cross-sectional study involving 1,568 Chinese men without diabetes.
• Utilized the homeostatic model assessment (HOMA) to calculate insulin resistance (HOMA-IR) and beta-cell function (HOMA-β).
• Employed general linear models and logistic regression to analyze associations between smoking status, intensity, and metabolic parameters.

Main Results:

• Current smokers exhibited higher 2-hour glucose levels and lower fasting insulin compared to never-smokers.
• Current smoking was significantly associated with impaired beta-cell function (HOMA-β), with a dose-dependent decrease observed as smoking intensity increased (P trend = 0.0026).
• No significant association was found between smoking status and insulin resistance (HOMA-IR).

Conclusions:

• Chronic smoking, particularly at higher intensities (≥20 pack-years), significantly suppresses insulin secretion capacity in Chinese men.
• The findings suggest that smoking primarily affects beta-cell function rather than causing insulin resistance in this population.
• Public health strategies should emphasize smoking cessation to mitigate risks of impaired glucose metabolism.