A pilot study to examine the effects of smoking cessation on serum markers of inflammation in women at risk for cardiovascular disease

Abstract

Background: The links among smoking, inflammation, and cardiovascular disease (CVD) are well established. Several studies have demonstrated that quitting smoking reverses the risk of coronary heart disease within 5 to 10 years. However, the immediate effects of quitting smoking on inflammatory biomarkers associated with CVD risk have not been well described.

Methods: In this pilot study, we examined a panel of circulating inflammatory biomarkers associated with CVD in "at-risk" women during the smoking cessation program. Forty-six women enrolled in a smoking cessation program consented to attend four study visits over 6 to 7 weeks. Health/medical information and blood were collected at each visit. Circulating levels of C-reactive protein (CRP), tumor necrosis factor (TNF), interleukin (IL)-6, soluble TNF receptor (sTNFR)-I, sTNFR-II, and soluble vascular cell adhesion molecule (sVCAM)-1 were measured, and changes between baseline levels (visit 1, while smoking) and visits 2 through 4 were determined.

Results: Significant reductions in circulating levels of TNF, sTNFR-I, sTNFR-II, and sVCAM-1 were observed among participants over the course of the smoking cessation program. Serum levels of both IL-6 and CRP declined during the smoking cessation program; the changes were not statistically significant, however.

Conclusions: These findings suggest there are rapid consequences of smoking cessation on inflammatory biomarkers in women at risk for CVD. Additional, larger studies including diverse smokers desiring to quit are required to confirm changes in "measurable milestones" that could serve as motivating factors to assist smokers to quit.

Figure 1.

Smoking cessation aids used by study subjects. Most study subjects used NRT (97%), the majority of individuals used NRT + bupropion (BUP), and 19% used NRT alone.

Figure 2.

Individual subject patterns of inflammatory mediators during the smoking cessation program. Individual subject patterns of serum inflammatory mediators (associated with increased risk of CVD) during the smoking cessation process (visits 1 through 4) are shown for TNF (A), sTNFR-I (B), sTNFR-II (C), sVCAM-1 (D), IL-6 (E), and CRP (F). Open symbols denote mediator values for individual subjects (taking NRT + bupropion) whose inflammatory mediators declined over the smoking cessation program; closed symbols denote values for individual subjects where no changes in inflammatory mediator levels were observed.