Impact of Dementia on Incidence and Severity of Postoperative Pulmonary Complications Following Hip Fracture Surgery Among Older Patients.

This was a retrospective observational study using electronic health records, so it cannot show that dementia caused the observed differences, and unmeasured confounding may remain. It was a single academic center in the southeast United States, so the results may not apply to all hip fracture patients. Dementia was identified from ICD-10 codes, and some dementia may have been undiagnosed or unaware; prolonged delirium could also have been misclassified as dementia. The study did not have an objective measure of dementia severity. Postoperative pulmonary complications and comorbidity scores relied on billing ICD-10 codes, which may be inaccurate or underestimate events. 277 patients with missing outcome data were excluded, which may affect the results. Five covariates had missing data and were imputed, so some baseline characteristics were not directly observed.

The authors reported no proprietary or commercial interest and declared no conflict of interest.

Do not read the 1.37-day longer hospital stay as proof that dementia caused it. This was an observational secondary outcome, and the primary postoperative pulmonary complication results were null.