PATTERNS OF ENDOSCOPY USE IN THE PROVINCE OF ALBERTA

RJ Hilsden

Departments of Medicine and Community Health Sciences, University of Calgary, Calgary, Alberta

EGD and colonoscopy play a critical role in the diagnosis and management of gastrointestinal conditions. The purposes of this study were (1) to determine trends in testing rates and (2) to detect significant regional variation in use, especially between urban and rural areas.
METHODS: In this population-based study, data on physician payments for EGD and colonoscopy from January 1, 1994 to March 31, 2000 were obtained from the Alberta Health Care Insurance Plan. Patients' postal codes were used to assign each to one of 17 health regions. Direct age-sex adjusted rates (per 1000 population) were calculated using annual health region population estimates and the 1996 Alberta population as the standard. Rates for 2000 were estimated from the 1st three months. To obtain stable rates for health regions, 3 northern regions were grouped together and three-year average rates were used.
RESULTS: The colonoscopy rate increased from 4.6 in 1994 to 8.0 in 2000. The EGD rates were more constant: 9.0 in 1994 and 10.8 in 2000. For both procedures, 60 - 64 year old men and women had similar rates, but prior to that age women had higher rates than men and after that age men had higher rates then women. The colonoscopy rate for 50 - 54 year old women was 14.5 and for men was 12.0. The rate for 70 - 74 year old women was 24.5 and for men was 28.1. There was significant regional variation in the 1997-1999 rates for colonoscopy and EGD (P < 0.0001). Regional colonoscopy rates varied from 3.8 to 10.6 and EGD rates from 6.6 to 22.2. The rates for the Calgary Health Region ranked lowest for EGD and 11th for colonoscopy. The corresponding ranks for the Capital Health Region (Edmonton) were 9th and 4th.
CONCLUSION: EGD rates have remained stable, whereas there has been a marked increase in colonoscopy rates. This may reflect the impact of colon cancer screening. Greater use of colonoscopy in women under age 60 may have a future impact on sex-specific colon cancer rates. Marked regional variations in rates exist, but no evidence that residents of the province's two large cities have greater access than those in more rural areas.