[Epidemiology of tonsillectomy and/or adenoidectomy in Italy].

OBJECTIVES AND METHODS: Aim of the study was to describe frequency, causes, regional variations, setting and risk of mortality of tonsillectomy and adenoidectomy in Italy. The study is based on hospital discharge data for the years 1998-2000 provided by the Ministry of Health. RESULTS: During the year 2000, 61.280 tonsillectomy with or without adenoidectomy and 32.655 adenoidectomy alone were performed in Italy. ICD-9-CM codes reported on discharge abstracts indicated that the most frequent causes of tonsillectomy were chronic tonsillitis (45%) and hypertrophy of tonsils and adenoids (43%). The total tonsillectomy rate was 10.6 x 10.000 (CI 10.5-10.7) in 2000, and it was stable throughout the study period. We observed a wide geographical variability of regional tonsillectomy rates, standardised by age and sex. They ranged from 3.5 x 10.000 (CI 3.1-4.0) in Basilicata to 19.0 (CI 18.6-19.5) in Piemonte. We found an inverse correlation (r = -0.50) between regional tonsillectomy rates for tonsillitis and minimum temperatures recorded in capitals of the regions. Most operations were performed in the acute setting with a hospital stay longer than one day. The mortality risk associated to surgery was estimated to be at least of one case over 95.000 operations. CONCLUSIONS: The observed variability of regional tonsillectomy rates, only partly explained by weather differences, may be ascribed to disagreement among physicians. Inappropriate variations and setting were the two main reasons conducive to the development of the guidelines "Clinical and organisational appropriateness of tonsillectomy and/or adenoidectomy in Italy", in the frame of LINCO project and of the Italian National Program for Guidelines.