OBJECTIVE: Comorbidity has a major impact on short-term and long-term survival of colorectal cancer (CRC) and many CRC patients suffer from comorbidities. Mortality rates for comorbidities like cardio-respiratory diseases exhibit distinct seasonal variations with highest rates in the winter. Therefore, we hypothesized some seasonal variation in 30-day mortality after surgery for CRC as well. METHOD: In a nationwide study, we examined the seasonal pattern in 30-day mortality after surgery for CRC from 1996 to 2006. We identified 33 556 CRC patients in the Danish hospital discharge registries. Monthly 30-day mortality rates were calculated and we constructed a fitted curve of the monthly mortality rates using a periodic regression model. We stratified the analyses for tumour site, urgency of surgery for colon cancer and the level of comorbidity based on American Society of Anaesthesiologists (ASA) score. RESULTS: The overall 30-day mortality was 8.7% [95% confidence interval 8.4-9.0%). Significant seasonal variation in monthly 30-day mortality could not be identified. For colon cancer, a nonsignificant increase was seen in July. An even higher increase in July was observed for CRC patients with moderate or severe comorbidity (ASA score >or= III), but was also nonsignificant. CONCLUSION: Although comorbidity is a well-known negative predictor of short-term survival of CRC, monthly 30-day mortality after surgery for CRC did not exhibit seasonal variation like that observed for comorbid conditions such as cardio-respiratory diseases.
OBJECTIVE: Comorbidity has a major impact on short-term and long-term survival of colorectal cancer (CRC) and many CRC patients suffer from comorbidities. Mortality rates for comorbidities like cardio-respiratory diseases exhibit distinct seasonal variations with highest rates in the winter. Therefore, we hypothesized some seasonal variation in 30-day mortality after surgery for CRC as well. METHOD: In a nationwide study, we examined the seasonal pattern in 30-day mortality after surgery for CRC from 1996 to 2006. We identified 33 556 CRC patients in the Danish hospital discharge registries. Monthly 30-day mortality rates were calculated and we constructed a fitted curve of the monthly mortality rates using a periodic regression model. We stratified the analyses for tumour site, urgency of surgery for colon cancer and the level of comorbidity based on American Society of Anaesthesiologists (ASA) score. RESULTS: The overall 30-day mortality was 8.7% [95% confidence interval 8.4-9.0%). Significant seasonal variation in monthly 30-day mortality could not be identified. For colon cancer, a nonsignificant increase was seen in July. An even higher increase in July was observed for CRC patients with moderate or severe comorbidity (ASA score >or= III), but was also nonsignificant. CONCLUSION: Although comorbidity is a well-known negative predictor of short-term survival of CRC, monthly 30-day mortality after surgery for CRC did not exhibit seasonal variation like that observed for comorbid conditions such as cardio-respiratory diseases.
Authors: Ju Young Choi; Sung-Ae Jung; Ki-Nam Shim; Won Young Cho; Bora Keum; Jeong-Sik Byeon; Kyu Chan Huh; Byung Ik Jang; Dong Kyung Chang; Hwoon-Yong Jung; Kyoung Ae Kong Journal: J Korean Med Sci Date: 2015-03-19 Impact factor: 2.153