The link between asthma and smoking explained by depressive feelings and self-efficacy

Objective: Adolescents with asthma consistently smoke at higher or similar rates as non-asthmatic peers, although smoking might involve more health risks. This study examined possible mechanisms (i.e. depressive feelings and self-efficacy to refrain from smoking) explaining the association between asthma and smoking initiation. Methods: An indirect path from asthma to self-efficacy through depressive feelings was examined in two independent samples. Sample 1 consisted of 4531 adolescents (mean age 12.8) and sample 2 consisted of 1289 children (late childhood, mean age 10.1). Data were gathered from maternal and self-report. In the adolescent sample, whether the relationship between depressive feelings at baseline and smoking initiation two years post-baseline runs via self-efficacy was also examined. Results: Higher amounts of depressive feelings decreased adolescents self-efficacy to refrain from smoking, which subsequently increased the risk to initiate smoking. A diagnosis of asthma was also associated with higher levels of depressive feelings which in turn decreased self-efficacy. A marginal significant indirect effect was found in the childhood sample. Conclusion: Smoking prevention efforts should start as early as mid to late childhood. The results indicate that focus should be placed on preventing depressive feelings with the aim of increasing children's self-efficacy to refrain from smoking. This is especially important for children and adolescents with asthma.