Effects of 1-year intermittent treatment with topical tacrolimus monotherapy on skin collagen synthesis in patients with atopic dermatitis

BACKGROUND: Topical corticosteroids decrease collagen synthesis during short-term treatment and can induce skin atrophy when applied over the long term. In contrast, short-term tacrolimus ointment therapy does not affect collagen synthesis. OBJECTIVES: Our aim was to evaluate the long-term effects of 0.1% tacrolimus ointment on collagen synthesis and on skin thickness in adults with moderate to severe atopic dermatitis (AD) and to compare the findings with the effects of conventional steroid-based therapy. METHODS: Fifty-six patients with AD were treated with 0.1% tacrolimus ointment in a 1-year, open-label, prospective clinical trial. Thirty-six patients with AD applied conventional steroid-based therapy and 27 healthy subjects were recruited as controls. The primary endpoint was the change in levels of procollagen propeptides I and III measured by radioimmunoassay between baseline and month 12. Additional endpoints included the change in skin thickness measured by ultrasound between baseline and month 12. RESULTS: Procollagen propeptide baseline values were significantly lower in the group to be treated with tacrolimus ointment than in healthy controls. One-year treatment with tacrolimus ointment was associated with an increase in collagen synthesis; the median increase in combined procollagen propeptide levels was 272 micro g L-1 (+ 140.9%, P < 0.001) and was accompanied by a significant increase in skin thickness. In three patients with visible skin atrophy, this condition ameliorated. Corticosteroid-based therapy had no significant effect on collagen synthesis; the median increase in combined procollagen propeptide levels was 11 micro g L-1 (+ 3.9%). A significant reduction in skin thickness was demonstrated. CONCLUSIONS: Long-term tacrolimus ointment therapy in patients with AD is nonatrophogenic and reverses corticosteroid-induced skin atrophy.