Appendectomy Appendectomy Appendectomy Appendectomy Appendectomy Appendectomy  Compared to Control  Compared to Control
No No No Yes Yes Yes
Variables
Events
PY
Rate#
Events
PY
Rate#
Crude HR (95% CI) Adjusted HR (95% CI)
Ulcerative colitis (UC) 49 1766861 2.77 116 1737942 6.67 2.40(1.72, 3..36)*** 2.23(1.59, 3.12)***
Age, years
≤34 15 704429 2.13 35 713152 4.91 2.31(1.26, 4.22)*** 2.17(1.18, 3.99)***
35-49 8 560303 1.43 27 553971 4.87 3.42(1.55, 7.52)*** 3.41(1.54, 7.54)**
>50 26 502128 5.18 54 470819 11.5 2.21(1.39, 3.53)*** 1.89(1.17, 3.04)**
Crohn’s’s disease (CD) 38 1766861 2.15 139 1737942 8.00 3.71(2.59, 5.31)*** 3.48(2.42, 4.99)***
Age, years
≤34 14 704429 1.99 66 713152 9.25 2.31(1.26, 4.22)*** 2.17(1.18, 3.99)*
35-49 5 560303 0.89 37 553971 6.68 3.42(1.55, 7.52)** 3.41(1.54, 7.54)**
>50 19 502128 3.78 36 470819 7.65 2.21(1.39, 3.53)*** 1.89(1.17, 3.04)**
Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001 Rate#: Incidence rate per 10 000 person years; Crude HR: relative hazard ratio; Adjusted HR: adjusted hazard ratio after control for sex and comorbidities of CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, and biliary stone; Comorbidity§: patients with CAD, hypertension, diabetes, hyperlipidemia, CVA, heart failure, COPD, CKD, alcohol-related diseases, cirrhosis, or biliary stone were classified as the comorbidity group. CAD, coronary artery disease; CI, confidence interval; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular disease; PY, person years; SD, standard deviation *P < .05, **P < .01, ***P < .001