Thymectomy, hospitalization up risk of adverse events after surgery in myasthenia gravis
Myasthenia gravis patients requiring hospitalization, emergency care and thymectomy appear to be at higher risks of adverse events following major surgery, a new nationwide matched cohort study reveals.
Medical and clinical information of 2,290 myasthenia gravis patients who underwent major surgery were retrieved from Taiwan’s National Health Insurance Research Database. A randomly selected control group (n=22,900) matched by propensity score was also established.
The primary outcome of the study was 30-day in-hospital mortality following surgery. Major complications such as pneumonia, septicaemia, stroke, bleeding, wound infection, acute myocardial infarction, acute renal failure and pulmonary embolism were assessed as secondary endpoints.
There was a higher overall risk of complications after surgery in patients with myasthenia gravis than in those without the neuromuscular disease (odds ratio [OR], 1.70; 95 percent CI, 1.44 o 2.00). Specifically, the risk of pneumonia (OR, 2.09; 1.65 to 2.65), septicaemia (OR, 1.31; 1.05 to 1.64) and bleeding (OR, 1.71; 1.07 to 2.72) were higher in myasthenia gravis patients.
The increased risk of postoperative complications was significant regardless of age group in both males (OR, 1.53; 1.18 to 1.97) and females (OR, 1.86; 1.50 to 2.31). Those without pre-existing medical conditions (OR, 2.15; 1.67 to 2.78) and with more than two conditions (OR, 1.56; 1.13 to 2.16) also have higher risks of postoperative complications.
Myasthenia gravis patients who received emergency care prior to operation (OR, 2.89; 1.99 to 4.21), thymectomy (OR, 3.71; 1.23 to 11.2) and who had been hospitalized (OR, 2.79; 2.20 to 3.52) also had increased risks of postoperative complications.
Low-income patients with myasthenia gravis (OR, 5.98; 3.12 to 11.5) had the highest risk of postoperative adverse events.