Effect of insulin-like growth factor-1 deficiency or administration on the occurrence of acne.

ABSTRACT

BACKGROUND: The role of growth hormone, insulin, and insulin-like growth factor-1 (IGF-1) in the development of acne is incompletely understood. OBJECTIVE: To study the effect of the absence of IGF-1 and its pharmacologic replacement on the occurrence of acne vulgaris. PATIENTS AND METHODS: Laron syndrome (LS) is characterized by congenital IGF-1 deficiency. The study group consisted of 21 patients with classical LS, who underwent puberty 13 (8 male, 5 female) untreated and under regular follow-up until age 20?48 years; and 8 (2 male, 6 female) treated with IGF-1 (70-200 µg/kg/day), including 6 adults (2 male, treated at age 14.5-29 years and 4 female, treated at age 30-37 years) and 2 adolescents (2 female, treated at age 3.5-16 years). The medical files were reviewed for occurrence of acne and the corresponding sex hormone levels, and the findings were compared between the treated and untreated patients. RESULTS: Puberty was delayed in all untreated patients. Only one patient had slight acne at age 22 years, when he reached full puberty. Among the 2 IGF-1 treated male patients, none acquired acne. Among the 6 treated female patients, 3 had signs of hyperandrogenism (oligo-amenorrhea) and acne during IGF-1 over-dosage. On reduction of the IGF-1 dose (to 50 µg/kg/day) or cessation of treatment, the acne disappeared in all 3 patients. CONCLUSION: This study demonstrates for the first time that serum IGF-1 deficiency prevents the occurrence of acne. The findings suggest that an interaction between IGF-1 and androgens is necessary for the development of acne.