The growth of life expectancy during the last decades has led to an increment in age-related conditions such as hip arthritis and fractures. On the other hand, these elderly patients will present a higher incidence of mental diseases which, in some studies, have been associated with inferior results.

This study aims to evaluate the differences in early complication rates between patients with cognitive impairment compared with those without this condition following total hip replacement for osteoarthritis or fracture in the context of contemporary perioperative care protocols.

We conducted a retrospective cohort study where cognitively-impaired patients who required primary hip arthroplasty were compared to a propensity-score matched cohort of patients without cognitive alterations. Early major complications were measured and analyzed in order to determine significant differences.

Screening and matching. 1196 patients were identified during the study period. After screening for inclusion and exclusion criteria and matching, two cohorts comprising 65 patients each were compared. After performing the propensity-score match, no significant differences were found in covariates between the two groups.

Outcomes. The occurrence of delirium was more frequent in patients with cognitive deficit (27.5%) than in the control group (9%), p<0.001. No significant differences were found among groups regarding myocardial infarction, venous thromboembolism, blood transfusion requirement, 30-day readmission, in-hospital death, 90-days death, dislocation or surgical site infection. The composite outcome of any adverse event did not exhibit a significant difference either.

To our knowledge, this is the first study which demonstrates similar outcomes between patients with cognitive impairment and those without these alterations. Our results might indicate that contemporary protocols and implants are bridging the traditional gap between these two populations. These findings support the use of total hip arthroplasty in patients with mental alterations when indicated, especially in those institutions with strict perioperative protocols.