Patients with rosacea were significantly more likely than controls to have Demodex mite infestation, according to findings from a literature review and meta-analysis.
The analysis included 1,513 patients from 23 case-control studies. Researchers examined prevalence and density of Demodex infestation among patients with rosacea, and performed a subgroup analysis for rosacea type.
Patients in the rosacea group were more than nine times more likely to have Demodex mites than controls (OR = 9.039; 95% CI, 4.827-16.925). Density of Demodex mites was also significantly greater in the rosacea group compared with controls (standardized mean difference = 1.617; 95% CI, 1.090-2.145).
Subtype analysis results indicated that Demodex mite density was significantly greater in both erythematotelangiectatic rosacea (standardized mean difference = 2.686; 95% CI, 1.256-4.116) and papulopustular rosacea (standardized mean difference = 2.804; 95% CI, 1.464-4.145), compared with controls.
Other findings indicated that Demodex mites occurred in 70.4% (range, 33.3%-100%) of patients with rosacea and 31.8% (range, 3.8%-96%) of controls. In the rosacea group, the mean density of mites was 71.0 mites/ cm2 (range, 1.9-376.8 mites/ cm2), while the density was 8.7 mites/cm2 (range, 0.06-89.6 mites/ cm2) among controls.
Study sampling methods or quality of evidence had no impact on Demodex mite prevalence rates, according to the findings. The researchers acknowledged inter-study variability, but found no evidence of publication bias in terms of prevalence or density of mites in patients or controls.
“Demodex mites may play a role in both erythematotelangiectatic rosacea and papulopustular rosacea,” the researchers concluded. – by Rob Volansky
Disclosures: The authors report no relevant financial disclosures.