Smell and taste function in subjects with chronic obstructive pulmonary disease : effect of long-term oxygen via nasal cannulas

It was hypothesized that subjects with chronic obstructive pulmonary disease (COPD) receiving long-term oxgen via nasal cannulas have an impaired sense of smell and/or taste. To objectively evaluate the sense of smell and taste, this study used the University of Pennsylvania Identification Test (UPSIT), a 40-item “scratch-n-sniff” test and a 20-item taste test using the four basic taste sensations of sweet, salt, sour, and bitter. Twenty subjects (15 male, 5 female) with severe COPD receiving long-term oxygen therapy (group 1), and an equal number of age- and sex-matched subjects with COPD not receiving oxygen therapy (group 2), and a healthy control group (group 3) were studied. Twelve subjects (seven male, five female) from group 1 subsequently underwent transtracheal oxygen catheter installation. Mean ± SD for the basic smell test was significantly greater in group 3 (35.35 ± 3.58) as compared with group 1 (27.70 ± 6.07) or group 2 (31.10 ± 4.95) (p