The relationship between executive dysfunction and neuropsychiatric symptoms in patients with Korsakoff’s syndrome

"Do not take that medication": negative prospective memory in Korsakoff's syndrome

BACKGROUND

While prospective memory (i.e., the ability to execute a future plan) has been extensively researched, little is known about negative prospective memory (i.e., the ability to remember not to execute a future plan) in Korsakoff's syndrome (KS). We thus evaluated both prospective memory and negative prospective memory in KS, as well as the relationship between both types of prospective memory and inhibition.

METHODS

Patients with KS and control participants were invited to press a button on the keyboard (i.e., prospective memory) or not to press a button when a cue word (e.g., negative prospective memory) was encountered.

RESULTS

The analysis demonstrated that patients with KS had more prospective memory errors (i.e., forgetting to click the keyboard when the instruction was to do so) than control participants. The analysis also demonstrated that patients with KS had more negative prospective memory errors (i.e., clicking the keyboard when the instruction was not to do so) than control participants. Similar levels of commissions and omissions were observed in patients with KS than in control participants. Interestingly, prospective and negative prospective performances were significantly correlated with performance on an inhibition assessment task.

DISCUSSION

Our study demonstrates that KS is characterized by not only difficulty in remembering to execute a future intention but also by difficulty in remembering not to execute a future intention. A decline in negative prospective memory in KS can be associated with difficulty in inhibiting no longer appropriate previously learned intentions.

Self-Reported Pain and Pain Observations in People with Korsakoff's Syndrome: A Pilot Study

Korsakoff's syndrome (KS) is a chronic neuropsychiatric disorder. The large majority of people with KS experience multiple comorbid health problems, including cardiovascular disease, malignancy, and diabetes mellitus. To our knowledge pain has not been investigated in this population. The aim of this study was to investigate self-reported pain as well as pain behavior observations reported by nursing staff. In total, 38 people diagnosed with KS residing in a long-term care facility for KS participated in this research. The Visual Analogue Scale (VAS), Pain Assessment in Impaired Cognition (PAIC-15), Rotterdam Elderly Pain Observation Scale (REPOS), and the McGill Pain Questionnaire-Dutch Language Version (MPQ-DLV) were used to index self-rated and observational pain in KS. People with KS reported significantly lower pain levels than their healthcare professionals reported for them. The highest pain scores were found on the PAIC-15, specifically on the emotional expression scale. Of importance, the patient pain reports did not correlate with the healthcare pain reports. Moreover, there was a high correlation between neuropsychiatric symptoms and observational pain reports. Specifically, agitation and observational pain reports strongly correlated. In conclusion, people with KS report less pain than their healthcare professionals indicate for them. Moreover, there is a close relationship between neuropsychiatric symptoms and observation-reported pain in people with KS. Our results suggest that pain is possibly underreported by people with KS and should be taken into consideration in treating neuropsychiatric symptoms of KS as a possible underlying cause.

Prevalences and Indications of Psychotropic Drug Prescriptions in Nursing Home Residents with Korsakoff Syndrome

Psychotropic drugs (PD) are often prescribed to nursing home residents with Korsakoff syndrome (KS). It is unknown whether these drugs are prescribed correctly or whether they are prescribed off-label, for example, to treat behavioral symptoms. To get more insight into PD prescriptions, a descriptive study was performed. The type, category and indications of PD prescriptions of 285 participants were analyzed using medication charts and questionnaires. Behavioral symptoms were investigated with the Neuropsychiatric Inventory-Questionnaire. The results showed that atypical antipsychotics (57.1%) were prescribed more frequently than typical antipsychotics (49.3%). Of the antidepressants, selective serotonin/norepinephrine reuptake inhibitors (63.1%) were most frequently prescribed, followed by tricyclic antidepressants (23.4%). Of the benzodiazepines, anxiolytics (85.7%) were more prescribed than hypnotics (24.5%). Besides psychiatric disorders, PD were also prescribed to treat behavioral symptoms varying from 29.9% (antipsycho-tics) to 26.3% (benzodiazepines) and 9.3% (antidepressants). Furthermore, prescriptions were high if behavioral symptoms were present. To conclude, PD are often prescribed to residents with KS for an unapproved indication, namely behavioral symptoms. Additional research is needed to obtain further insight into the current prescribing culture and the effectiveness of PD. The insights thus obtained may, ultimately, contribute to the appropriate prescription of PD for people with KS.

"Ten dollars today or 50 dollars after one month?" Temporal discounting in Korsakoff syndrome

OBJECTIVE

Little research has investigated decision making in patients with Korsakoff syndrome (KS). Specifically, to our knowledge, there is a lack of research investigating whether patients with KS may tend to prefer immediate over future rewards (i.e., temporal discounting). Further, we investigated the relationship between temporal discounting and inhibition.

METHODS

We, for the first time, invited patients with KS and control participants to perform a temporal discounting task, in which they answered questions probing preferences between an immediate, but smaller amount of money, and a delayed, but larger amount of money (e.g., "would you prefer 10 dollars today or 50 dollars after one month?"). Furthermore, inhibition was measured using the Stroop Colour Word Test.

RESULTS

Analysis demonstrated higher temporal discounting in patients with KS than in control participants. Temporal discounting in both populations was significantly correlated with inhibition.

CONCLUSIONS

Patients with KS may have difficulties to suppress the temptation of smaller, but immediate, rewards.