Modifications in nasal function and nitric oxide serum level in type 1 diabetes.
OBJECTIVE
In this study, we evaluated the modifications of nasal function in type 1 diabetes (insulin-dependent diabetes mellitus [IDDM]) by active anterior rhinomanometry (AAR) to understand if involvement of the nasal nervous system and microcirculation could be detected in nasal mucosa.


METHODS
We studied 35 nonsmoking IDDM patients without diabetic complications, nasal pathology, or septal deviation. We measured serum levels of nitric oxide (NO) and nasal airway in three conditions: basal, supine, and after decongestion (phenylephrine hydrochloride 0.25 mg spray) by means of rhinomanometry, determining inspiratory total resistance and nasal airflow. The rhinomanometric results of the IDDM patients were compared with those of control normal subjects. In the IDDM patients, neuropathy was evaluated according to standardized procedures, including the vibration perception threshold test, cardiovascular autonomic tests, conduction velocity test, and fundoscopic examination.


RESULTS
The NO serum level was significantly higher in IDDM patients (12.5 +/- 3.8) compared with normal controls (4.8 +/- 1.4). The AAR results showed that in IDDM patients, inspiratory total resistance in the basal (0.82 +/- 0.4 Pa/cm3) and supine (0.94 +/- 0.7 Pa/cm3) positions and after decongestion (0.59 +/- 0.2 Pa/cm3) were increased compared with the control group in three conditions (basal, 0.52 +/- 0.2 Pa/cm3; supine, 0.58 +/- 0.3 Pa/cm3; after decongestion, 0.48 +/- 0.2 Pa/cm3). After decongestion, there was a greater decrease in nasal resistance in diabetic patients than in normal subjects.


CONCLUSIONS
Nasal function is involved in IDDM, rhinomanometry can also be considered an important test in the evaluation of this involvement in patients without other signs of diabetic neuropathy, and an increase in NO could partially explain these alterations.
Di Nardo
Walter
W
Department of Otolaryngology, Catholic University of the Sacred Heart Rome, Rome, Italy.
Pitocco
Dario
D
Di Leo
Mauro A S
MA
Picciotti
Pasqualina M
PM
Di Stasio
Enrico
E
Collina
Chiara
C
Santini
Stefano
S
Scarano
Emanuele
E
Ghirlanda
Giovanni
G
D000328:Adult; D000403:Airway Resistance; D001786:Blood Glucose / Q000032:analysis; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009296:Nasal Cavity / Q000503:physiopathology; D009297:Nasal Mucosa / Q000503:physiopathology*; D015508:Nasal Obstruction / Q000175:diagnosis* / Q000209:etiology; D009569:Nitric Oxide / Q000097:blood* / Q000378:metabolism; D011336:Probability; D012016:Reference Values; D025363:Rhinomanometry / Q000379:methods*; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D055815:Young Adult
D001786:Blood Glucose; D009569:Nitric Oxide