Sex differences in the association between smoking and central sensitization: A cross-sectional study

Despite the acknowledged interconnection between smoking and pain, research on the relationship between smoking and central sensitization (CS) is scarce; this pain mechanism has attracted recent research attention. Considering potential sex differences, this cross-sectional study aimed to investigate the association between smoking and CS.

Overall, 415 adult participants from an outpatient clinic underwent evaluation. The analysis focused on determining the relationship between smoking status and CS by differentiating between sexes. Data were collected on smoking presence or absence (independent variable) and CS (dependent variable) for each sex, with age, education level, drinking history, depression, and anxiety as covariates. CS was evaluated using the Central Sensitization Inventory. Following a descriptive analysis of the study population's characteristics, logistic regression analysis was employed to assess the relationships.

The average participant age was 42.3 years, with 59% being women. Among women, a significant association was found between smoking status and higher CS severity (AOR=3.21; 95% CI 1.29-7.99, p<0.01), after accounting for confounding variables. Conversely, no significant association was observed for men (AOR=1.50; 95% CI 0.63-3.60, p=0.36). Interaction by sex on the relationship between smoking and CS was not statistically significant (p=0.23).

This study suggests a potential association between smoking and CS in women, whereas no conclusive relationship was observed among men. These findings indicate the necessity of considering CS when examining the relationship between smoking and pain.