Low bone mineral density in adult patients with moderate to severe atopic dermatitis

Abstract

Atopic dermatitis (AD) is a chronic inflammatory skin disease commonly treated with topical corticosteroids. The inflammatory nature of this disorder and the use of topical corticosteroids represent potential risk factors for bone loss. The aim was to assess the prevalence of osteoporosis and osteopenia in adult patients with moderate to severe AD. In addition, the associations between topical/oral corticosteroid use and bone mineral density (BMD) and between disease activity and BMD were studied. We studied 125 adult patients with moderate to severe AD. Using dual-energy X-ray absorptiometry, BMD was measured at lumbar spine and hips. The cumulative dose of topical and oral corticosteroids was calculated from pharmacy prescription records. Lifestyle parameters were collected by a questionnaire. Biochemical parameters of bone metabolism and disease activity [serum concentration of thymus and activation-regulated chemokine (TARC) levels] were also measured. Osteoporosis was documented in six patients (4.8%) and osteopenia in 41 patients (32.8%); 30.4% of the patients had a Z-score <or= -1 (low BMD), with more men (43.8%) than women (16.4%) affected. There was no significant association between low BMD and biochemical parameters of bone metabolism, serum TARC levels and cumulative dose of topical and oral corticosteroids during the 5 years prior to inclusion. We document a Z-score <or= -1 in about one-third of predominantly male patients with moderate to severe AD, being independent of the cumulative dose of topical and corticosteroids used within 5 years prior to study. Whether the relatively high prevalence of low BMD is due to the cumulative dose of topical corticosteroids beyond 5 years prior to the study or the chronicity of the underlying inflammatory process or a combination of these, remains to be established.