[Appendicitis and appendectomy in Norway 1990-2001].

BACKGROUND: The purpose of this study was to examine the incidence of appendicitis and appendectomy in Norway from 1990 to 2001.

METHODS: Data were compiled from the Norwegian Patient Registry based on ICD-9 and ICD-10 codes for appendicitis and appendectomy. Re-admissions after appendectomy were selected based on institution and allocation numbers for hospitalisation.

RESULTS: Age-adjusted incidence rates for appendectomy were 117 per 100 000 for men and 116 per 100 000 for women. Incidence rates were highest among patients aged 10-29. Diagnostic accuracy increased from 81% to 86% in men and from 60% to 71% in women over the study period. Perforation ratio increased from 12% to 21% in men and from 9% to 17% in women. Appendectomy by laparoscopic technique increased during 1998 to 2001 from 5% to 10% of cases for men and from 9% to 15% of cases for women. The proportion of laparoscopic appendectomy was considerably higher in two counties (50% and 28% in 2000-2001). Length of hospital stay was shorter after laparoscopy (median two days) than after open surgery (median three days), with no difference in the rate of re-admission of 4%.

INTERPRETATION: Diagnostic accuracy and perforation ratio increased over the 1990s. Patients operated upon with laparoscopic technique had shorter hospital stays and the same re-admission rate compared to patients undergoing conventional surgery. Though the proportion of appendectomies done by laparoscopy doubled from 1998 to 2001, the procedure is not in commonly use in Norway.