Poor nutritional status in patients with cystic fibrosis (CF) is associated with increased mortality. Patients with CF often have a decreased sensation of smell secondary to recurrent sinus infections or sinus surgery; in other CF populations, a decreased sensation of smell has been associated with poor nutritional status. We hypothesized that a decreased sensation of smell would be associated with worse nutritional status in patients with CF. We studied 50 (26 F and 24 M) of 58 consecutive patients with CF (86%) aged 14-53 years (28 +/- 8; mean +/- SD) who attended the University of Washington Medical Center from June 1994 to March 1995 and who agreed to participate. Demographic information was obtained, and nutritional status was assessed by ideal body weight, arm muscle area, arm fat area, pancreatic sufficiency, insulin-requiring diabetes, vitamins A and E levels, albumin, iron, iron binding capacity, ferritin, cholesterol, and zinc levels. Objective sensation of small was examined (Sensonics, Philadelphia, PA), a sinus compacted tomogram (CT) was performed, and a questionnaire for prior sinus symptoms, sinus surgery, medications, and subjective sensation of smell was administered. Twenty-seven of 49 subjects (55%) had an objective decrease in sensation of smell, 23/50 (46%) had had prior sinus surgery. 46/50 (92%) were pancreatic insufficient, and 8/50 (16%) were insulin-requiring diabetics. Weight for height ranged from the 38th to 157th percentile (100 +/- 18; mean +/- SD). Arm muscle area ranged from the < 5th to the 75th percentile (25 +/- 23; mean +/- SD). Arm fat area ranged from the < 5th to the 95th percentile (45 +/- 39; mean +/- SD). Sinus CT scans were abnormal in all patients (100%). Patients with anosmia were more likely to have had sinus surgery, but their nutritional status was no different from that of patients with a normal sensation of smell. We conclude that decreased sensation of smell is common in patients with CF, especially those with prior sinus surgery. Subjective sensation of smell and sinus CT scans were unreliable indicators of a decreased objective sensation of smell. In this pilot study, no association was found between sensation of smell and nutritional status.