Increased Age, Cardiovascular Comorbidities, COPD, and Diabetes mellitus Determine Excess Mortality in Trauma Patients with SSI or Chronic Wounds.

Background: The constant aging of the German population leads, among other things, to an increase in the average age of hospitalised patients. In association with the reduced physiological reserve and the endogenous defence mechanism, this results in an increased susceptibility to infections and complications. Compared with that in trauma patients, the age distribution in patients with surgical site infections (SSI) has been poorly studied. Studies on the impact of age, diverse underlying diseases and influence of alcohol and nicotine consumption on the mortality risk in patients with SSI are limited.

Methods: In 2014/15 (Exam 1), 345 patients with SSI were included in this study. The 3-year follow-up examination was performed in 2017/18 (Exam 2). The questionnaires (Exams 1 and 2) assessed demographic parameters, comorbidities, medication use, alcohol and nicotine consumption, and different risk factors related to morbidity. The mortality risk in patients with SSI was calculated as a function of various risk factors (age, comorbidities, medication intake, and noxious agents). Furthermore, the development of the patients' age in the trauma department, especially of those with SSI, were evaluated between 2010 and 2019.

Results: In 2014/15 (Exam 1), 345 patients were included in the study. Of these, 274 (79.4%) were contacted by telephone in 2017/18. Thirty-six (10.4%) declined to be questioned again. Twenty (8.4%) of the 238 remaining participants had already died, resulting in 218 patients (63.2%) re-participating. From 2010 (n = 492) to 2019 (n = 885), the number of patients with SSI increased by 79.9%, especially those aged < 65 years. After the age of 60 years, the mortality risk increased rapidly (60 years: 0.0377 vs 70 years: 0.1395); the mortality risk of a 60-year-old patient with SSI was equal to that of an 80-year-old in the general population. Nicotine (p = 0.93) and alcohol consumption (p = 0.344) had no significant effect on mortality, whereas history of cardiac disease (p = 0.01), chronic obstructive pulmonary disease (COPD) (p = 0.01), diabetes mellitus (p = 0.05) and peripheral artery disease (p = 0.01) were associated with a significant increase in the mortality risk.

Conclusion: Age, pre-existing cardiac conditions, as well as COPD, diabetes mellitus and peripheral artery disease are associated with a significantly increased mortality risk in patients with SSI. Thus, an exponential increase in mortality risk was found between the ages of 50 and 60 years, with the mortality risk of a 60-year-old patient with SSI being equivalent to that of an 80-year-old in the general population.