Oxandrolone Improves Height Velocity and BMI in Patients with Cystic Fibrosis

Cystic fibrosis (CF) is an autosomal recessive disorder that features chronic pulmonary disease, pancreatic insufficiency, and other organ involvement. Patients with CF often have malnutrition and short stature. According to the Cystic Fibrosis Foundation Patient Registry 2007 Annual Data Report, 21% of patients with CF had weight less than the 10th percentile, while 13% had height below the 5th percentile [1]. Malnutrition and poor growth velocity are associated with declining pulmonary function, morbidity, and mortality [2–5]. Steady improvements in nutritional status are associated with greater pulmonary function [6], and evidence-based practice recommendations strongly advise close monitoring of growth and nutritional status as well as aggressive nutritional intervention for patients with CF [7].Multiple agents have been used to stimulate appetite and growth in patients with CF, but their utility has been limited due to side effects (such as adrenal suppression with megestrol) or cost (such as growth hormone). Oxandrolone is a relatively weak androgen that stimulates appetite and promotes linear growth and has been safely used to treat a variety of conditions associated with wasting, poor weight gain, or short stature [8]. Furthermore, oxandrolone is an attractive option in growing children because it cannot be aromatized to estrogen, and therefore estrogen-dependent advancement of the bone age is minimized. To our knowledge, there are no reports in the literature of the use of oxandrolone in patients with CF.For the past 4 years, children with CF referred to our endocrine clinic for persistent growth concerns in spite of other nutrition-augmentation strategies have occasionally been treated with oxandrolone. This retrospective analysis evaluates the effectiveness of oxandrolone in improving the weight gain and linear growth of these patients.We reviewed the medical records of all patients in our endocrine clinic with CF who were treated with oxandrolone for at