Causes of death among patients surviving at least one year following splenectomy

To assess the mortality (mostly long-term sequelae) of patients undergoing splenectomy, we carried out a population-based study in Sweden.

Using the unique personal identification number assigned to each Swedish resident, we linked centralized hospitalization records with nationwide mortality data. After initially assessing risks within the first 12 months after splenectomy, we excluded deaths during the first year and computed standardized mortality ratios (SMRs) for 1,297 patients splenectomized for external trauma and 991 surgically treated for nonmalignant conditions of adjacent organs who were alive at 12 months following surgery. The general Swedish population was used as the comparison.

Both men and women undergoing splenectomy for external trauma had a 1.6-fold (SMR = 1.6) significantly elevated mortality risk, due mainly to circulatory diseases (particularly thromboembolism), alcoholism, digestive disorders, and external causes. Men also had a 28-fold increased mortality from septicemia and an excess of liver cirrhosis (mostly alcohol-related). Patients of both genders splenectomized for nonmalignant conditions had small but significantly elevated mortality overall (SMR = 1.4 to 1.5) reflecting excess risks for malignancies, diseases of blood-forming organs, external causes, and circulatory, respiratory, and digestive disorders. In addition, men had increased mortality from thromboembolism and pneumonia while women experienced elevated risks from septicemia.

The excess mortality resulted from functional postsplenectomy defects (including sepsis and thromboembolism), behaviors increasing risk of traumatic splenic injury (eg, alcoholism), damage to other organs from the external trauma (eg, traumatic injury to the central nervous system/spinal cord), or the same or recurrent nonmalignant conditions for which surgery was performed (eg, gastric and duodenal ulcers).