Relative skeletal muscle mass is negatively associated with increased rosacea severity, which suggests that skeletal muscle could be protective against rosacea exacerbation, according to a study published in The Journal of Dermatology.
As skeletal muscle mass has been shown to help prevent metabolic syndrome, and rosacea is believed to be associated with many of the factors involved in metabolic syndrome, researchers in the current cross-sectional study investigated the link between rosacea severity and relative muscle mass. Study participants were patients at the Kangbuk Samsung Hospital Health Screening Center in Korea who attended the hospital’s skin checkup program between 2014 and 2016.
Dermatologists took and evaluated polarized light photographs of the participants’ faces, and the participants’ skeletal muscle index (SMI) was estimated via a bioelectrical impedance analyzer (%=total skeletal muscle mass in kg/bodyweight in kg×100). The associations between SMI and rosacea severity were evaluated using a logistic regression model.
Of 110 total participants, 84.5% (n=93) were diagnosed with erythematotelangiectatic rosacea and 15.5% (n=17) with papulopustular rosacea. Participants were divided into the following tertiles of SMI ranges: 22.86% to 38.40% (T1, low SMI), 38.41% to 43.44% (T2, medium SMI), and 43.45% to 80.65% (T3, high SMI).
Mild rosacea was seen in 75.5% (n=83) of participants, moderate rosacea in 24.5% (n=27) of participants, and severe rosacea in 0 participants. A significant decreasing trend was seen in rosacea severity with increasing SMI (P <.05). When comparing SMI T1 and SMI T2 to SMI T3 (reference) for moderate rosacea, the prevalence ratios were 4.68 (95% CI, 1.06-20.75) for T1 and 4.29 (95% CI, 1.17-15.80) for T2.
This association was not observed for mild rosacea. After the findings were analyzed according to sex, this association was observed in women with marginal significance (Ptrend =.06) but was inconspicuous in men.
Study investigators conclude that “it is likely that SM is a protective factor for severe rosacea.”
Nam JH, Yang J, Park J, et al. Association between rosacea severity and relative muscle mass: a cross-sectional study [published online October 31, 2018]. J Dermatol. doi: 10.1111/1346-8138.14689