Abstract
BACKGROUND Postoperative wound disruption and tissue-destructive disorders are more frequent in smokers than in nonsmokers. Impaired wound healing and altered connective tissue turnover are suggested mechanisms, but exact details remain unknown. METHODS Full-thickness, 5-mm punch biopsy wounds were made lateral to the sacrum in 48 smokers and were randomized double-blinded to continuous smoking, abstinence with transdermal nicotine patch (TNP), or abstinence with placebo patch and 30 never smokers. At 1, 4, 8, and 12 weeks, the wounds were excised and fixed for wound measurement, and blood was collected for measurement of vitamin C, procollagen I N-propeptide (PINP), matrix metalloproteinase 8 (MMP), MMP-9, neutrophils, and eosinophils. RESULTS One week after wounding, smokers' wounds were 3.1 ± 0.1 mm (mean, standard error of the mean) wide and were 1.3 ± 0.1 mm deep compared with the never smokers' wounds, measuring 3.7 ± 0.1 mm wide and 1.5 ± 0.1 mm deep (P < .01, respectively). Abstinent smokers' wounds were 3.3 ± 0.1 mm wide (NS) and were 1.4 ± 0.1 mm deep (P = .02 compared with smokers). In smokers, vitamin C and PINP were 50.5 ± 9.0 μmol/L and were 52.7 ± 6.6 ng/mL, respectively, compared with 68.8 ± 14.5 μmolL and 64.7 ± 4.7 ng/mL in never smokers (P < .001 and P = .07). Both increased significantly after smoking cessation. Plasma MMP-8 and MMP-9 were correlated with neutrophil blood count, which significantly was affected by smoking status. No effect of TNP was found. CONCLUSION Smokers have smaller, more superficial wounds and lesser blood levels of vitamin C and PINP. Smoking cessation resulted in increased wound depth, vitamin C, and PINP as well as a decreased neutrophil blood count. These findings suggest that wound contraction and collagen metabolism are affected by a smoking-induced alteration in vitamin C turnover and by a change in inflammatory cell response.
