RESUMEN
BACKGROUND: Skin signs observed in morbid obesity may change as the weight reduces, especially post-bariatric surgery (BaS). Data concerning the skin findings exclusively in post-BaS patients remain limited. METHODS: Seventy post-BaS patients were examined for cutaneous abnormalities. The patients were divided into those with successful weight loss (% excessive body weight loss (EBWL) of at least 50%) and a non-successful group (%EBWL < 50%). RESULTS: Forty-six patients with successful weight loss demonstrated a significantly lower prevalence of acanthosis nigricans on the neck, axillae and inguinal areas, keratosis pilaris (KP) and pebble fingers. However, a higher prevalence of alopecia was observed. After adjustment with patients' factors, KP (adjusted odds ratio (aOR) = 0.21, 95%CI 0.06-0.74, p = 0.02) and pebble fingers (aOR = 0.09, 95%CI 0.01-0.89, p = 0.04) remained significantly less likely in patients with successful weight loss. Laboratory results comparing pre- and post-surgery values revealed significant decreases in fasting plasma glucose, hemoglobin A1c, and triglyceride and an increase of high-density lipoproteins in both groups. However, significant decreases of liver aminotransferases (AST and ALT) were observed only in the successful group (p = 0.04, 0.003). Nonetheless, a decrease in vitamin B12 (p = 0.01) was observed in the successful group. CONCLUSION: Weight loss after BaS provided an improvement for metabolic profiles. Successful weight reduction resulted in better skin improvement. However, nutritional supplements may be necessary. TRIAL REGISTRATION: Thai Clinical Trials Registry TCTR20171003002 . Registered October 3. 2017, retrospectively registered.