Hair loss in females after sleeve gastrectomy: predictive value of serum zinc and iron levels.

A common complication after bariatric surgery is hair loss, which is related to rapid weight reduction, but zinc, iron, and other micronutrient deficiencies can also be involved. Little is studied after laparoscopic sleeve gastrectomy (LSG). A prospective observational study was performed of 42 morbidly obese females undergoing LSG. Incidence of hair loss was monitored. Micronutrients were investigated preoperatively and three, six, and 12 months after surgery. Sixteen patients (41%) reported hair loss in the postoperative course. A significant association was observed between hair loss and zinc levels (P = 0.021) but mean zinc levels were within the normal range in patients reporting hair loss. Only three patients (7.7%) presented low zinc levels, all of them reporting hair loss. There was also a significant association between iron levels and alopecia (P = 0.017), but mean values of the patients with hair loss were within normal range. Only four patients (10.2%) presented low iron levels, all of them presenting hair loss. A variable consisting of the addition of zinc + iron showed a significant association with hair loss (P = 0.013). A cutoff point was established in 115 (odds ratio, 4; P = 0.006). All the patients but two reporting hair loss presented addition levels under 115. This variable showed sensibility 88 per cent, specificity 84 per cent, positive predictive value 79 per cent, and negative predictive value 91 per cent to predict hair loss. Hair loss is a frequent condition after sleeve gastrectomy. In most cases, iron and zinc levels are within the normal range. The variable addition (zinc + iron) is a good predictor of hair loss. Patients with addition levels below 115 are fourfold more susceptible to present hair loss. In these cases, zinc supplements achieve the stop of hair loss in most cases.