The trajectory of C-reactive protein serum levels in older hip fracture patients with postoperative delirium.

OBJECTIVES: Important precipitating risk factors for delirium such as infections, vascular disorders, and surgery are accompanied by a systemic inflammatory response. Systemic inflammatory mediators can induce delirium in susceptible individuals. Little is known about the trajectory of systemic inflammatory markers and their role in the development and outcome of delirium. METHODS: This is a prospective cohort study of older patients undergoing acute surgery for hip fracture. Baseline characteristics were assessed preoperatively. During hospital admission, presence of delirium was assessed daily according to the Confusion Assessment Method criteria. This study compared the trajectory of serum levels of the C-reactive protein (CRP) between people with and without postoperative delirium. Blood samples were taken at baseline and at postoperative day 1 through postoperative day 5. RESULTS: Forty-one out of 121 patients developed postoperative delirium after hip fracture surgery. Longitudinal analysis of the trajectory of serum CRP levels using the Generalized Estimating Equations (GEE) method identified that higher CRP levels were associated with postoperative delirium. CRP levels were higher from postoperative day 2 through postoperative day 5. No significant differences in serum CRP levels were found when we compared patients with short (1-2 days) and more prolonged delirium (3 days or more). CONCLUSIONS: Delirium is associated with an increased systemic inflammatory response, and our results suggest that CRP plays a role in the underlying (inflammatory-vascular) pathological pathway of postoperative delirium.

Affective functioning after delirium in elderly hip fracture patients.

BACKGROUND: Delirium in elderly patients is associated with various long-term sequelae that include cognitive impairment and affective disturbances, although the latter is understudied. METHODS: For a prospective cohort study of elderly patients undergoing hip fracture surgery, baseline characteristics and affective and cognitive functioning were assessed preoperatively. During hospital admission, presence of delirium was assessed daily. Three months after hospital discharge, affective and global cognitive functioning was evaluated again in patients free from delirium at the time of this follow-up. This study compared baseline characteristics and affective functioning between patients with and without in-hospital delirium. We investigated whether in-hospital delirium is associated with increased anxiety and depressive levels, and post-traumatic stress disorder (PTSD) symptoms three months after discharge. RESULTS: Among 53 eligible patients, 23 (43.4%) patients experienced in-hospital delirium after hip fracture repair. Patients who had experienced in-hospital delirium showed more depressive symptoms at follow-up after three months compared to the 30 patients without in-hospital delirium. This association persisted in a multivariate model controlling for age, baseline cognition, baseline depressive symptoms, and living situation. The level of anxiety and symptoms of PTSD at follow-up did not differ between both groups. CONCLUSION: This study suggests that in-hospital delirium is associated with an increased burden of depressive symptoms three months after discharge in elderly patients who were admitted to the hospital for surgical repair of hip fracture. Symptoms of depression in patients with previous in-hospital delirium cannot be fully explained by persistent (sub)syndromal delirium or baseline cognitive impairment.

The neuropsychological sequelae of delirium in elderly patients with hip fracture three months after hospital discharge.

BACKGROUND: Delirium is a risk factor for long-term cognitive impairment and dementia. Yet, the nature of these cognitive deficits is unknown as is the extent to which the persistence of delirium symptoms and presence of depression at follow-up may account for the association between delirium and cognitive impairment at follow-up. We hypothesized that inattention, as an important sign of persistent delirium and/or depression, is an important feature of the cognitive profile three months after hospital discharge of patients who experienced in-hospital delirium. METHODS: This was a prospective cohort study. Fifty-three patients aged 75 years and older were admitted for surgical repair of acute hip fracture. Before the surgery, baseline characteristics, depressive symptomatology, and global cognitive performance were documented. The presence of delirium was assessed daily during hospital admission and three months after hospital discharge when patients underwent neuropsychological assessment. RESULTS: Of 27 patients with in-hospital delirium, 5 were still delirious after three months. Patients with in-hospital delirium (but free of delirium at follow-up) showed poorer performance than patients without in-hospital delirium on tests of global cognition and episodic memory, even after adjustment for age, gender, and baseline cognitive impairment. In contrast, no differences were found on tests of attention. Patients with in-hospital delirium showed an increase of depressive symptoms after three months. However, delirium remained associated with poor performance on a range of neuropsychological tests among patients with few or no signs of depression at follow-up. CONCLUSION: Elderly hip fracture patients with in-hospital delirium experience impairments in global cognition and episodic memory three months after hospital discharge. Our results suggest that inattention, as a cardinal sign of persistent delirium or depressive symptomatology at follow-up, cannot fully account for the poor cognitive outcome associated with delirium.

Validation and psychometric properties of the Delirium Motor Subtype Scale in elderly hip fracture patients (Dutch version).

The Delirium Motor Subtype Scale (DMSS) was developed to capture all the previous different approaches to delirium motor subtyping into one new instrument and emphasize disturbances of motor activity rather than associated psychomotoric symptoms. We investigated reliability and validity of the DMSS Dutch version. Elderly patients who had undergone hip fracture surgery received the DMSS and the Delirium Rating Scale Revised-98 (DRS-R-98). A diagnosis of delirium was defined according to the Confusion Assessment Method (CAM). Among 146 patients, 46 (32%) patients were diagnosed with delirium (mean age 86.3 years; SD 5.2). The internal consistency of the DMSS was acceptable (Cronbach's alpha=0.72). If an item was removed at random the internal consistency of the scale remained the same. Similarly the concurrent validity of DMSS was good (Cohen's kappa=0.73) while for each motor subtype the Cohen's kappa ranged from 0.58 to 0.85. The sensitivity and specificity of DMSS to detect each subtype ranged from 0.56 to 1 and from 0.88 to 0.98, respectively. This study suggests that the Dutch version of the DMSS is a reliable and valid instrument. The DMSS has scientific validity that could allow for greater precision in further research on motor subtypes.

Reliability of delirium rating scale (DRS) and delirium rating scale-revised-98 (DRS-R98) using variance-based multivariate modelling.

Delirium's characteristic fluctuation in symptom severity complicates the assessment of test-retest reliability of scales using classical analyses, but application of modelling to longitudinal data offers a new approach. We evaluated test-retest reliability of the delirium rating scale (DRS) and delirium rating scale-revised-98 (DRS-R98), two widely used instruments with high validity and inter-rater reliability. Two existing longitudinal datasets for each scale included DSM-IV criteria for delirium diagnosis and repeated measurements using the DRS or DRS-R98. To estimate the reliability coefficients RT and RΛ for each scale we used a macros provided by Dr. Laenen at http://www.ibiostat.be/software/measurement.asp. For each dataset a linear mixed-effects model was fitted to estimate the variance-covariance parameters. A total of 531 cases with between 4 and 9 measurement points across studies including both delirious and non-delirious patients. Comorbid dementia in the datasets varied from 27% to 55%. Overall RT for the DRS were 0.71 and 0.50 and for DRS-R98 0.75 and 0.84. RΛ values for DRS were 0.99 and 0.98 and for DRS-R98 were 0.92 and 0.96. Individual RT measures for DRS-R98 and DRS across visits within studies showed more range than overall values. Our models found high overall reliability for both scales. Multiple factors impact a scale's reliability values including sample size, repeated measurements, patient population, etc in addition to rater variability.

Delirium motor subtypes in elderly hip fracture patients: risk factors, outcomes and longitudinal stability.

OBJECTIVE: Delirium is often accompanied by changes in motor activity but the longitudinal expression of these features and etiological and prognostic significance of clinical subtypes defined by motor activity is unclear. METHODS: This is a prospective cohort study of elderly patients undergoing hip fracture surgery. Baseline characteristics were assessed preoperatively. During hospital admission presence of delirium was assessed daily according to CAM criteria. This study compared baseline characteristics and outcomes according to a longitudinal pattern of motor subtype expression (predominantly hyperactive, predominantly hypoactive, predominantly mixed, no motor subtype and variable). Motor subtype categorization was performed with the DRS-R98. We also investigated the longitudinal stability of motor subtypes across the delirium episode. RESULTS: 62 patients had experienced in-hospital delirium postoperatively. The full course of the delirium episode could be defined for 42/62 (67.7%) patients. Of the patients with multiple days of delirium only 4/30 (13.3%) patients had a consistent motor subtype profile throughout the delirium episode, while 26/30 (86.7%) patients had a variable course. Of the patients with multiple days of delirium, 5/30 (16.7%) were predominantly hypoactive in profile, 7/30 (23.3%) predominantly hyperactive, 6/30 (20%) predominantly mixed, 1/30 (3.3%) had no motor subtype and 11/30 (36.7%) had a variable profile. Baseline characteristics and outcomes did not differ between the groups. CONCLUSION: The majority of elderly hip fracture patients in this homogenous sample experienced variable expression of motor subtype over the course of their delirium episodes. The subtype categorization according to dominant motor subtype across the delirium episode identified groups with similar characteristics and outcomes.

Predicting delirium duration in elderly hip-surgery patients: does early symptom profile matter?

Background. Features that may allow early identification of patients at risk of prolonged delirium, and therefore of poorer outcomes, are not well understood. The aim of this study was to determine if preoperative delirium risk factors and delirium symptoms (at onset and clinical symptomatology during the course of delirium) are associated with delirium duration. Methods. This study was conducted in prospectively identified cases of incident delirium. We compared patients experiencing delirium of short duration (1 or 2 days) with patients who had more prolonged delirium (≥3 days) with regard to DRS-R-98 (Delirium Rating Scale Revised-98) symptoms on the first delirious day. Delirium symptom profile was evaluated daily during the delirium course. Results. In a homogenous population of 51 elderly hip-surgery patients, we found that the severity of individual delirium symptoms on the first day of delirium was not associated with duration of delirium. Preexisting cognitive decline was associated with prolonged delirium. Longitudinal analysis using the generalised estimating equations method (GEE) identified that more severe impairment of long-term memory across the whole delirium episode was associated with longer duration of delirium. Conclusion. Preexisting cognitive decline rather than severity of individual delirium symptoms at onset is strongly associated with delirium duration.

Anesthesia and postoperative delirium in older adults undergoing hip surgery.

OBJECTIVES: To examine the effects of general anesthesia on the risk of incident postoperative delirium in older adults undergoing hip surgery. DESIGN: Secondary analysis of haloperidol prophylaxis for delirium clinical trial data. Predefined risk factors for delirium were assessed prior to surgery. Primary outcome was postoperative delirium. Study outcome was compared across patient groups who received either general or regional anesthesia, and for individuals receiving various perioperative medications (benzodiazepines, anticholinergics, and opioids), using multivariable logistic regression after controlling for potential confounders. Subgroup analyses based on baseline cognitive impairment and delirium risk were also undertaken. SETTING: Large medical school-affiliated general hospital in Alkmaar, the Netherlands. PARTICIPANTS: Five hundred twenty-six adults aged 70 and older undergoing hip surgery. MEASUREMENTS: The primary outcome was the incidence of postoperative delirium (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and Confusion Assessment Method criteria). RESULTS: Sixty participants (11.4%) had incident postoperative delirium. One hundred eighty-nine (35.9%) received general anesthesia, 18 (9.5%) of whom developed postoperative delirium, and 337 (64.1%) received regional anesthesia, 42 (12.5%) of whom developed postoperative delirium (adjusted odds ratio=0.81, 95% confidence interval=0.43-1.52, P=.51). Results were stratified for baseline cognitive impairment, age, acute admission, perioperative medication and other delirium risk factors. Delirium was not independently associated with specific drugs or the medication classes opioids, benzodiazepines, and anticholinergics. CONCLUSION: General anesthesia has no distinct effect on incident postoperative delirium in older adults undergoing hip surgery. This also holds for individuals suffering from cognitive impairment or who are otherwise at risk for postoperative delirium. Perioperative use of narcotics, benzodiazepines, and anticholinergic agents was not associated with incident delirium in this cohort of older adults undergoing hip surgery.