The effects of pre-existing dementia on surgical outcomes in emergent and nonemergent general surgical procedures: assessing differences in surgical risk with dementia

BACKGROUND: The aim was to assess the morbidity and in-hospital mortality that occur in surgical patients with pre-existing dementia compared with those outcomes in non-dementia patients following emergent and nonemergent general surgical operations. METHODS: A total of 120 patients with dementia were matched for sex and type of surgery with 120 patients who did not have dementia, taken from a cohort of 15,295 patients undergoing surgery, in order to assess differences in surgical risk with dementia. Patient information was examined, including sex, body mass index (BMI), prevalence of individual comorbidities at admission, and several other variables that may be associated with postoperative outcomes as potential confounders. RESULTS: Patients with dementia tended to have a higher overall complication burden compared to those without. This was evidenced by a higher average number of complications per patient (3.30 vs 2.36) and a higher average score on the comprehensive complication index (48.61 vs 37.60), values that were statistically significant for a difference between the two groups. The overall in-hospital mortality in patients with dementia was 28.3% (34 deaths out of 120 patients). During the same period, at our hospital, the overall in-hospital mortality in the control group was 20% (24 deaths out of 120 patients). Patient groups with and without dementia each had 3 and 5 associated risk factors for morbidity and 9 and 12 risk factors for mortality, respectively. CONCLUSIONS: Patients with pre-existing dementia have a greater than average risk of early death after surgery, and their incidence of fatal complications is higher than that of surgical patients without dementia.