Interrelationship of Postoperative Delirium and Cognitive Impairment and Their Impact on the Functional Status in Older Patients Undergoing Orthopaedic Surgery: A Prospective Cohort Study

Abstract

BackgroundThe impact of postoperative delirium on post-discharge functional status of older patients remains unclear, and little is known regarding the interrelationship between cognitive impairment and post-operative delirium. Therefore, the main purpose was to evaluate the post-discharge functional status of patients who experience delirium after undergoing orthopaedic surgery and the interrelationship of postoperative delirium with underlying cognitive impairment.MethodThis prospective cohort study, conducted at a tertiary care medical center from April 2011 to March 2012, enrolled all subjects aged over 60 years who were admitted for orthopaedic surgery. The baseline characteristics (age, gender, BMI, and living arrangement), surgery-related factors (ASA class, admission type, type of surgery, and length of hospital stay), results of geriatric assessment (postoperative delirium, cognition, depressive mood, comorbidity, pain, malnutrition, polypharmacy, ADL, and instrumental [I]ADL) and 1–12-month postoperative ADL and IADL functional status were collected for analysis.ResultsOverall, 9.1% of 232 patients (mean age: 74.7±7.8 years) experienced postoperative delirium, which was significantly associated with IADL decline at only 6 and 12 months postoperatively (RR: 6.22, 95% CI: 1.08–35.70 and RR: 12.54, 95% CI: 1.88–83.71, respectively). Delirium superimposed on cognitive impairment was a significant predictor for poor functional status at 6 and 12 months postoperatively (RR: 12.80, 95% CI: 1.65–99.40 for ADL at the 6th month, and RR: 7.96, 95% CI: 1.35–46.99 at the 12th month; RR: 13.68, 95% CI: 1.94–96.55 for IADL at the 6th month, and RR: 30.61, 95% CI: 2.94–318.54 at the 12th month, respectively).ConclusionPostoperative delirium is predictive of IADL decline in older patients undergoing orthopaedic surgery, and delirium superimposed on cognitive impairment is an independent risk factor for deterioration of ADL and IADL functional status. Early identification of cognitive function and to prevent delirium are needed to improve functional status following orthopaedic surgery.

Association between Cognitive Status before Surgery and Outcomes in Elderly Patients with Hip Fracture in a Dedicated Orthogeriatric Care Pathway

“…Comparisons between 3 groups were performed using a Kruskal Wallis test for quantitative variables, followed by a Dunn test when a significant difference was found; and Fisher's exact method for qualitative variables. Survival and the risk of a new institutionalization in the 3 groups of patients were estimated by a multivariate logistic regression analysis and for survival by the Kaplan-Meier method too (differences were assessed by the log-rank test) adjusted for the factors known in the published literature [6,[12][13][14][15]19,26,33,34] (semi-parsimonious method): age (< 80,81-85, 86-90, > 90), sex (female as reference), comorbidities (CIRS-G, ≤ or > 8) [29], number of drugs per day (< or ≥ 5), prefracture ADL6 (≤ 5 or = 6) [30], the ability to walk without assistance before surgery, time-tosurgery (≤ or > 48 hours) and the occurrence of delirium during hospitalization. We tested the association of survival / new institutionalization and cognitive status before surgery in UPOG by calculating the odds ratio (OR) or Hazard ratio (HR) and their 95 percent confidence interval (CI) with these prognostic variables.…”

“…Delirium is common after hip fracture surgery (occurring in 35% to 65% of patients) [37], frequently associated with preexisting cognitive impairment and it is predictive of functional decline, institutionalization, and mortality [33,37]: each day of delirium increased the risk of death within 6 months by 17% [34].…”

Risk factors for delirium after cardiac surgery: a historical cohort study outlining the influence of cardiopulmonary bypass

“…Previous studies have supported a link between delirium and POCD, suggesting that the cognitive disturbance seen in each condition may be related (13, 14). Investigators have evaluated whether or not differences in POCD exist between patients exposed to CPB and those not exposed during cardiac surgery.…”

We can Do it: Nursing Educational Intervention to Increase Delirium Documentation

“…Often underrecognized, if left untreated delirium is associated with serious health and quality-of-life consequences, including increased risk of morbidity and mortality, as well as greater functional dependence after discharge. Overall delirium incidence ranges widely, from 14-56% of hospitalized older patients, with a reported 9-65% incidence in those patients undergoing orthopedic fracture repair [2][3][4][5][6].…”