Association Between Cigarette Smoking and Diabetic Foot Healing: A Systematic Review and Meta-Analysis

Abstract

The role of smoking for wound healing in patients with diabetic foot has been unclear. This meta-analysis examined the relationship between cigarette smoking and diabetic foot wound healing. Observational studies for the association between smoking and diabetic foot wound healing of patients were systematically searched through PubMed and Wanfang Data, published up to June 2018. Healing rates of wounds were recognized as outcomes. Meta-analysis models were chosen by heterogeneity. A total of 3388 eligible studies were identified, of which 18 met all our inclusion criteria. In the smoking group, healing rate had an average of 62.1%, ranging from 20.0% to 89.6%; in the nonsmoking group, healing rate had an average of 71.5%, ranging from 40.2% to 93.8%. A significant association was found between smoking and the healing of diabetic foot wounds (z = 3.08; P = .002), with an odds ratio (OR) of 0.70 (95% CI = 0.56-0.88), based on a random-effects model. Meta-regression analyses indicated that the heterogeneity did not come from publication year (t = −0.50, P = .622) or overall healing rate (t = 0.16, P = .872). The leave-one-out sensitivity analysis was robust; sensitivity analysis for pooled estimate of adjusted ORs had an OR of 0.20 (95% CI = 0.07-0.56; z = 3.08; P = .002). Subgroup analysis had an OR of 0.62 (95% CI = 0.41-0.95; z = 2.21; P = .027) in retrospective cohort studies and had an OR of 0.75 (95% CI = 0.57-0.99; z = 2.02; P = .043) in prospective cohort studies. Our meta-analysis indicated that smoking had an overall negative effect on the wound healing of diabetic foot individuals. This study provides evidence for the harm of smoking to diabetic foot and may help reduce the medical and economic burden on poor healing of diabetic foot.

To Smoke or Not To Smoke: Cigarettes Have a Negative Effect on Wound Healing of Diabetic Foot Ulcers

“…Healing rates were lower in smokers (mean = 62.1%, range = 20.0% to 89.6%) than in nonsmokers (mean = 71.5%, range = 40.2% to 93.8%). 15 In subgroup analysis, the retrospective cohort group had an OR of 0.62 (95% CI = 0.41-0.95, P = .009) and the prospective cohort had an OR of 0.75 (95% CI = 0.57-0.99, P = .0064). 15 This meta-analysis provides evidence for the harmful effect of smoking on healing rates of diabetic foot ulcers.…”

“…15 In subgroup analysis, the retrospective cohort group had an OR of 0.62 (95% CI = 0.41-0.95, P = .009) and the prospective cohort had an OR of 0.75 (95% CI = 0.57-0.99, P = .0064). 15 This meta-analysis provides evidence for the harmful effect of smoking on healing rates of diabetic foot ulcers. In the same context, a recent study has reported that current smoking was independently associated with 30-day unplanned rehospitalization in patients with diabetic foot after adjustment for confounders (OR = 1.95, 95% CI = 1.02-3.73).…”

“…16 The main strength of this study is the leave-one-out sensitivity analysis, which confirmed the robustness of the meta-analysis. 15 Moreover, 18 studies with as many as 5819 subjects were included. 15 So far, there has been only one analysis on the detrimental effect of smoking on diabetic foot ulcers, but it has provided rather limited evidence owing to the small number of studies included, most of them case series.…”

“…15 Moreover, 18 studies with as many as 5819 subjects were included. 15 So far, there has been only one analysis on the detrimental effect of smoking on diabetic foot ulcers, but it has provided rather limited evidence owing to the small number of studies included, most of them case series. 17 The limitations of this meta-analysis are the significant publication bias (the authors only included English and Chinese literature) and the moderate heterogeneity of included studies.…”

“…Finally, the authors failed to analyze the association between wound healing and passive smoking, smoking cessation, or smoking for different durations. 15 Based on this new evidence on the detrimental effect of smoking on healing rates of diabetic foot ulcers, 15 it is reasonable to consider the utility of smoking cessation programs. Incorporation of the latter into the multidisciplinary therapeutic strategy for the diabetic foot may be anticipated to improve healing rates, but this remains to be shown.…”