Table 1.
Case-crossover analysis comparing the incidence of invasive procedures (IPs) in the 3-month case period and the preceding 12-month control period for 14 731 patients admitted with IE
| Invasive procedures (ISPs) | Case period (3 m) | Control period (12 m) | Unadjusted step model† | Adjusted step model‡ | Adjusted hinge model§ | |||||||
| Total proc* | Proc/m* | Total proc* | Proc/m* | OR | 95% CI | OR | 95% CI | P value | OR | 95% CI | P value | |
| Cardiac procedures | ||||||||||||
| Coronary angiography | 366 | 122 | 991 | 82.6 | 1.48 | 1.31 to 1.67 | 1.05 | 0.88 to 1.25 | 0.776 | 1.04 | 0.97 to 1.12 | 0.403 |
| Coronary artery bypass graft (CABG) | 12 | 4 | 12 | 1 | 4 | 1.80 to 8.91 | 2.99 | 0.75 to 11.96 | 0.253 | 1.62 | 0.96 to 2.73 | 0.132 |
| Percutaneous coronary procedures and stent implantation | 54 | 18 | 97 | 8.1 | 2.25 | 1.61 to 3.15 | 1.59 | 0.94 to 2.68 | 0.211 | 1.28 | 1.03 to 1.58 | 0.066 |
| Implantation of cardiac pacemakers/defibrillators | 463 | 154.3 | 672 | 56 | 2.81 | 2.50 to 3.17 | 1.54 | 1.27 to 1.85 | <0.001 | 1.29 | 1.19 to 1.39 | <0.001 |
| Percutaneous valve procedures | 9 | 3 | 29 | 2.4 | 1.25 | 0.59 to 2.66 | 2.57 | 0.78 to 8.45 | 0.278 | 1.61 | 0.99 to 2.60 | 0.115 |
| Dental procedures | ||||||||||||
| Extractions or surgical removal of teeth | 54 | 18 | 81 | 6.8 | 2.68 | 1.90 to 3.78 | 2.14 | 1.22 to 3.76 | 0.047 | 1.27 | 1.02 to 1.59 | 0.082 |
| Other oral surgical procedures | 13 | 4.3 | 25 | 2.1 | 2.10 | 1.07 to 4.12 | 1.59 | 0.56 to 4.53 | 0.590 | 1.14 | 0.75 to 1.75 | 0.687 |
| Scaling and gingival procedures | 1 | 0.3 | 1 | 0.1 | 4 | 0.25 to 63.92 | 2.99 | 0.02 to 363.52 | 0.753 | 0.55 | 0.08 to 4.04 | 0.611 |
| ENT procedures | ||||||||||||
| Tonsillectomy and adenoidectomy | 2 | 0.7 | 6 | 0.5 | 1.33 | 0.27 to 6.61 | 0.28 | 0.03 to 2.39 | 0.472 | 0.58 | 0.21 to 1.56 | 0.376 |
| Nasal packing/nasal intubation | 23 | 7.7 | 59 | 4.9 | 1.60 | 0.97 to 2.64 | 0.71 | 0.35 to 1.44 | 0.572 | 0.99 | 0.73 to 1.33 | 0.925 |
| GI procedures | ||||||||||||
| Upper GI endoscopic procedures (gastric, duodenum, jejunum, ileum) | 627 | 209 | 1014 | 84.5 | 2.59 | 2.34 to 2.87 | 1.58 | 1.34 to 1.85 | <0.001 | 1.30 | 1.22 to 1.39 | <0.001 |
| Lower GI endoscopic procedures (including sigmoid and rectum) | 333 | 111 | 656 | 54.7 | 2.07 | 1.81 to 2.37 | 1.66 | 1.35 to 2.04 | <0.001 | 1.23 | 1.13 to 1.34 | <0.001 |
| Colonic surgery (including appendicectomy) | 28 | 9.3 | 59 | 4.9 | 1.9 | 1.21 to 2.98 | 1.48 | 0.74 to 2.95 | 0.467 | 1.01 | 0.76 to 1.35 | 0.911 |
| Endoscopic retrograde cholangio-pancreatic procedures | 25 | 8.3 | 57 | 4.8 | 1.81 | 1.12 to 2.94 | 0.94 | 0.46 to 1.89 | 0.853 | 0.78 | 0.57 to 1.06 | 0.198 |
| GU procedures | ||||||||||||
| Cystoscopy procedures | 155 | 51.7 | 501 | 41.8 | 1.26 | 1.05 to 1.53 | 0.92 | 0.70 to 1.20 | 0.775 | 0.94 | 0.83 to 1.05 | 0.391 |
| Endoscopic prostate procedures | 38 | 12.7 | 108 | 9 | 1.41 | 0.97 to 2.05 | 0.55 | 0.33 to 0.92 | 0.084 | 0.72 | 0.57 to 0.91 | 0.019 |
| Haematology procedures | ||||||||||||
| Blood transfusion/red cell/plasma exchange | 295 | 98.3 | 660 | 55 | 2.84 | 2.35 to 3.43 | 1.33 | 1.01 to 1.76 | 0.129 | 1.2 | 1.07 to 1.35 | 0.012 |
| Bone marrow puncture | 99 | 33 | 144 | 12 | 2.96 | 2.27 to 3.87 | 1.76 | 1.16 to 2.69 | 0.039 | 1.28 | 1.08 to 1.52 | 0.018 |
| Obstetric and gynaecological procedures | ||||||||||||
| Abortion/dilatation and curettage | 4 | 1.3 | 11 | 0.9 | 1.46 | 0.46 to 4.63 | 1.69 | 0.29 to 9.72 | 0.754 | 2.07 | 0.99 to 4.33 | 0.120 |
| Vaginal delivery | 7 | 2.3 | 29 | 2.4 | 0.97 | 0.42 to 2.20 | 0.96 | 0.31 to 2.98 | 0.898 | 1.34 | 0.83 to 2.15 | 0.380 |
| Caesarean delivery | 2 | 0.7 | 10 | 0.8 | 0.8 | 0.18 to 3.65 | 0.71 | 0.10 to 5.24 | 0.805 | 1.28 | 0.56 to 2.94 | 0.639 |
| Respiratory procedures | ||||||||||||
| Bronchoscopic procedures | 51 | 17 | 72 | 6 | 2.88 | 2.00 to 4.13 | 1.87 | 1.04 to 3.34 | 0.118 | 1.33 | 1.06 to 1.68 | 0.049 |
| Skin procedures | ||||||||||||
| Skin and wound management procedures | 107 | 35.7 | 295 | 24.6 | 1.46 | 1.17 to 1.83 | 0.92 | 0.67 to 1.27 | 0.765 | 0.96 | 0.84 to 1.10 | 0.600 |
P values in red=significant positive association between the ISP and subsequent IE after Benjamini-Hochberg correction. P values in purple=significant negative association between ISP and subsequent IE after Benjamini-Hochberg correction.
*A maximum of one procedure of each type per patient was counted each month.
†Period-adjusted OR of ISPs in case period (3 months prior to IE admission) compared with the 12 month control period (15 to 4 months prior to IE admission) calculated using a mixed-effects logistic regression model with the patient as the random effect.
‡OR of ISPs in case period (3 months prior to IE admission) compared with control period (15 to 4 months prior to IE admission) calculated using a mixed-effects logistic regression model adjusted for the month (1–15) and date of IE admission (with the patient as the random effect).
§OR of ISPs for each month increase in the case period (3 to 1 months prior to IE admission) compared with control period (15 to 4 months prior to IE admission) calculated using a mixed-effects logistic regression model adjusted for month and date of IE admission (with patient as the random effect).
IE, infective endocarditis; ISPs, invasive procedures; m, month; proc, procedures.