Association between keloids and atopic dermatitis: a cross-sectional study at a tertiary care center

Keloid scars are a result of aberrant would healing due to inflammation or skin trauma that can cause pruritus, contractures and pain. Recent literature suggests a potential association between atopy and keloids. Thus, the primary goal of this study was to assess the association between keloids and atopic dermatitis in a diverse patient population. EPIC was utilized to collect anonymous, aggregate-level data on patients 18 years or greater seen at the Johns Hopkins Hospital System (JHHS) from 4/4/2013 to 12/19/18. Data for keloid scar development was collected for patients diagnosed with the top 15 Medicare conditions, including atopic dermatitis and asthma. Patients were compared to race-matched controls and significance assessed using chi-square testing. Bonferroni correction was performed to control for multiple hypothesis testing. Of the 4,877,856 patients in our database, 3,527 patients were diagnosed with keloids. Of these patients, 25.72% were white and 59.51% were black. Among all the variables, keloids were most strongly associated with atopic dermatitis (OR 16.11, p <0.0001) and asthma (OR 6.11, p<0.0001), which are both signs of atopy. This observation remained significant in race-stratified analyses. Among the comorbidities assessed, patients with keloids had an increased likelihood of the following conditions: hypertension (OR 4.44, p<0.001), chronic hepatitis (OR 4.02, p<0.0001), HIV infection (OR 4.77, p<0.0001), diabetes mellitus type 2 (OR 3.89, p<0.0001), chronic kidney disease (OR 3.87, p<0.0001), and ischemic heart disease (OR 3.21, p<0.0001). Mast cell overactivity may be a potential mechanism to explain the association between keloids and atopic dermatitis. Future studies should examine mechanistic explanations for the association between keloids and atopy.