Association of active and passive smoking with noncommunicable diseases in a large health check-up population: A cross-sectional study in Changzhi, Shanxi province, China

The overall prevalence of current smoking in the health check-up population was 27.3%, with a large sex disparity.

• Total current smoking prevalence was 27.3% across 38,906 adults aged ≥18 years.
• Prevalence was 51.3% in men and only 0.3% in women.
• The study was conducted in Changzhi, Shanxi Province, China from January to December 2025.
• 26.2% of all participants had at least one clinically diagnosed NCD.

Active smoking was independently associated with increased odds of having a non-communicable disease after full adjustment for confounders.

• The adjusted odds ratio (AOR) for active smoking and NCDs was 1.26 (95% CI: 1.18–1.35).
• Adjustment included demographics and lifestyle habits as potential confounders.
• The association remained statistically significant at p<0.05.
• Multivariable logistic regression was the analytic method used.

A modest dose-response gradient between smoking duration and NCD odds was observed, with the highest risk among those smoking ≥25 years.

• Compared with <5 years of smoking, AOR was 1.24 (95% CI: 1.08–1.43) for 5–14 years.
• AOR was 1.23 (95% CI: 1.09–1.39) for 15–24 years of smoking.
• AOR was 1.37 (95% CI: 1.19–1.58) for ≥25 years of smoking.
• The authors described the pattern as 'a modest dose-response gradient' for smoking duration.
• Dose-response relationships for smoking duration were also observed in subgroup analyses for specific NCDs.

Daily cigarette consumption of ≥20 cigarettes was modestly associated with elevated NCD risk, but lower consumption levels did not show a clear gradient.

• Daily consumption of ≥20 cigarettes yielded an AOR of 1.13 (95% CI: 1.03–1.25).
• The association was described as 'modest'.
• The paper does not report statistically significant associations for lower daily consumption categories in the abstract.
• The dose-response for daily consumption appeared less pronounced than that for smoking duration.

The crude association between secondhand smoke (SHS) exposure and NCDs was statistically significant, but attenuated to non-significance after adjustment for confounders.

• The unadjusted (crude) OR for SHS and NCDs was 1.25 (95% CI: 1.16–1.35), which was statistically significant.
• After full adjustment for potential confounders, the AOR was 1.04 (95% CI: 0.95–1.13), which crossed the null.
• The authors noted this attenuation 'highlights the challenge of isolating its independent role in observational settings.'
• The study captured SHS exposure via questionnaire interview.

In subgroup analyses, active smoking was specifically associated with hypertension, diabetes, cardiovascular disease, and dyslipidemia.

• These four NCDs were identified in subgroup analyses as individually associated with active smoking.
• Dose-response relationships for smoking duration were also observed within these specific NCD subgroups.
• The subgroup analyses were conducted within the same cross-sectional study population of 38,906 adults.
• Specific AORs for each NCD subgroup were not reported in the abstract.

The study was a large cross-sectional analysis of adults undergoing routine health check-ups in Changzhi, Shanxi Province, China.

• Total sample size was 38,906 adults aged ≥18 years who were local residents.
• Data were collected from January to December 2025.
• Tobacco smoke status (active smoking, SHS exposure, daily cigarette consumption, and smoking duration) and NCDs were captured via questionnaire interview and clinical diagnosis.
• The cross-sectional design limits causal inference.