Speed of Processing Training for Cognitive Deficits After Delirium in Older Adults

The overall goal of this project is to measure longitudinal cognitive function among hospitalized older adults after an episode of delirium, and examine an intervention (processing speed training, or PST) to slow the rate of cognitive decline that occurs after an episode of delirium compared to an Internet-based control condition (INT). We will initially recruit a cohort of 136 subjects who have experienced delirium, provide PST or INT training to them, and assess them on measures of cognition and instrumental activities of daily living (IADLs) after training and every 6 months thereafter for 24 to 36 months. We will perform a preliminary determination of the efficacy of PST after these 136 subjects have completed training, testing whether subjects receiving PST have better cognitive test scores immediately after training compared to subjects receiving INT. Assuming this preliminary test of efficacy shows short-term benefits for PST, we will recruit an additional 280 subjects who have experienced delirium and provide PST training to them. We will follow all 416 subjects for 24 to 36 months after their delirium episode to test whether subjects receiving PST have slower rates of decline over time compared to subjects receiving INT on measures of cognition and IADLs. A more detailed timeline of study procedures follows.

In Hospital (Month 0): We will initially identify subjects with delirium from the inpatient medical units at UAB Hospital. As part of UAB's Virtual ACE quality improvement project, nurses on the medical units administer the Nursing Delirium Screening Scale (NUDESC) to screen for delirium in all patients age ≥ 65 on admission and once per shift thereafter. After obtaining informed consent, we will collect a range of measures from the subject and family to make the diagnosis of delirium and rate its severity, as well as measures examining comorbidities potentially contributing to delirium. These measures for assessing delirium will be

• the NUDESC ratings from the medical record;
• the Confusion Assessment Method (CAM), a standard clinician-rated instrument for the diagnosis of delirium;
• the Delirium Symptom Interview (DSI), an interview administered by a clinician to standardize the assessment of delirium symptoms for rating the CAM;
• the Cognitive Test for Delirium (CTD), a general measure of cognition used to standardize the assessment of cognitive symptoms for rating the CAM;
• the Family Confusion Assessment Method (FAMCAM), which assesses the family's observation of symptoms of delirium (although this will not be required for delirium diagnosis);
• the chart-based review method for delirium (CHART-DEL), which collects information from the medical records about signs and symptoms that can indicate delirium;
• the Delirium Etiology Rating Checklist (DERC), a clinician-rated instrument that categorizes the different potential causes of delirium for the subject, based on information in the medical record on other medical conditions, current medications, neuroimaging (CT or MRI, if available), abnormal laboratory values (complete blood count, serum electrolytes and chemistries, liver function tests, and urine drug screen, if available);
• the Anticholinergic Burden Scale (ABS), which rates the contribution of the subject's medications to their episode of delirium.

Additional measures collected on comorbidities and factors affecting delirium will be

• demographics (age, race, gender);
• the AD8 and the Modified Blessed Dementia Rating Scale, which assess the family's observations of symptoms of dementia that preceded the episode of delirium;
• the Charlson Comorbidity Index (CCI), which assesses the presence of other medical conditions beyond delirium.