Skin ulcers in systemic sclerosis: Determinants of presence and predictive factors of healing

Association between cigarette smoking and impaired clinical symptoms in systemic sclerosis: A review

“…For example, in a study conducted at Johns Hopkins Medical Center in Baltimore (involving 98 patients 13% of whom were smokers, with smoking assessed as never, former, or current), smoking was not a risk factor for digital ulceration or amputation [28]. In contrast, in a subsequent study conducted at Hope Hospital in Manchester, UK (involving 101 patients, 21% of whom were smokers, with smoking assessed as never, past, or current and as pack-years), current smokers were 3-4 times more likely than never smokers to incur digital vascular complications [18]. However, past smokers were not at increased risk compared with never smokers.…”

“…However, due to using simple exposure variables (self-described ever, never or pack-year smoking) that may have resulted in so-called'healthy smoker bias'in which an individual who smokes may a priori have lungs that are more resistant to the effects of smoking. Fortunately, other investigators [11] appear to have addressed this controversy by using the comprehensive smoking index (CSI) which integrates parameters related smoking intensity, duration and time since cessation into a single covariate of smoking effect. One expected benefit of the complexity of the CSI is that it is expected to capture more fully and accurately the effect of smoking, as compared with simpler smoking covariates.…”

“…But nothing is known about the effect of smoking on skin disease in SSc. To study the effect of cigarette smoking on the extent of skin disease in SSc, a recent 20-month follow-up study in Italian was performed [18], the researchers observed that there was no statistically significant difference in smoking habits between the two groups of patients with or without skin ulcers (P = 0.274).…”

“…The products of combustion can be divided into gaseous and particulate components, both of which contain extremely high concentrations of free radicals and cigarette smoke activates endogenous sources of free radicals as well. Reactive oxidative species (ROS) produced from the metabolism of constituents of tobacco smoke and free radicals can interact with DNA, and could cause genetic mutations [18]. Indeed, a significantly higher risk of anti-dsDNA seropositivity in current smokers with SLE than in never smokers has been demonstrated.…”

“…Fourth, cigarette smoking has anti-estrogenic effects through the formation of inactive 2-hydroxy catechol estrogens [18]. Estrogens can affect the Thl/Th2 immune balance and estrogens have either pro-or anti-inflammatory actions depending on the estrogen/androgen balance [45].…”