Poster - "Fatigue, Cognitive Function, and Sleep Quality in Patients with Chronic Hepatitis C

Bailey Presents at 2012 State of the Science Congress on Nursing Research

September 30, 2012
Friday, September 28, 2012
Source

Chip Bailey presented a poster entitled "Fatigue, Cognitive Function, and Sleep Quality in Patients with Chronic Hepatitis C (CHC)" at the Council for the Advancement of Nursing Science 2012 State of the Science Congress on Nursing Research in Washington, D.C., September 13-15. He co-authored the abstract with Shelly Epps, Trina Walker, Justin Levens, Karin Weissenborn, Richard Keefe, and Hans L. Tillmann.

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Fatigue, Cognitive Function, and Sleep Quality in Patients with Chronic Hepatitis C (CHC)

Authors:
Donald E. Bailey, Jr. 1
Shelly Epps 2
Trina Walker 3
Justin Levens 2
Karin Weissenborn 4
Richard Keefe 3
Hans L. Tillmann 3

1 Duke University School of Nursing, Durham, NC;
2 Duke Office of Clinical Research, Durham, NC;
3 Duke University School of Medicine, Durham, NC;
4 Department of Neurology, Medizinische Hochschule, Hannover, Germany

Background
Fatigue is a frequent complaint in CHC patients. CHC patients also often experience problems with cognitive function: difficulties with attention, concentration, memory.

Study Aims
Describe cognitive processing difficulties in adults with CHC. Explore relationship of cognitive function in these patients with fatigue, sleep quality, and disease stage.

Sample (n=29)
Adult patients with CHC:
*18 with fatigue
*11with no fatigue
*Convenience sample
* Recruited at Duke University Medical Center, Gastroenterology Clinic
*Baseline data for sample demographic and clinical characteristics are shown in tables

Measures
Fatigue: Revised Piper Fatigue Scale (PFS).
*22-item scale (each item scaled 0-10); use summary score.
*Summary score scaled 0-10 (higher score indicates more fatigue).
*Administered only to patients reporting fatigue (n=18)

Sleep Quality:
*Sleep Timing & Sleep Quality Screening Questionnaire: 1 item
Disease Stage and Disease Grade :
*Clinical data abstracted from medical record

Measures of Cognitive Function
*Brief Assessment of Cognition (BAC) includes 6 tasks:
List Learning -- Verbal Memory
Digit Sequencing Task -- Working Memory
Token Motor Task – Motor Spped Verbal Fluency
Semantic/Letter Fluency Tower of London
Reasoning & Problem Solving / Executive Function Symbol Coding
Attention and Processing Speed

B. Continuous Phase Trials – Identical Pairs (CPT – IP)
Measures Sustained Attention and Vigilance

Analysis
* Standardized z-scores calculated for BAC cognitive function test (based on comparisons with normative healthy control sample). Separate z-scores for each of the 6 BAC measures; BAC composite z-score

*Means, 95% CI for BAC task & composite scores calculated for:
CHC patients with fatigue (n=18) vs. without fatigue (n=11) Patients at each disease grade (0-3; measures inflammation) Patients at each disease stage (I-IV; measures fibrosis)

*Mann-Whitney rank sum test used to compare z-scores on BAC and CPT-IP score for CHC patients with vs. without fatigue.

*Pearson correlation used to evaluate relationships between BAC z-scores and PFS fatigue scores, sleep quality ratings.

Results

HCV patients in this study showed significant impairment independent of fatigue for 3 of the 6 BAC tasks.

In the graphs below, z-score for healthy controls on each task = 0.0 (shown in graphs below as a red dotted line)

Mean z-scores for all HCV patients were significantly lower than healthy control scores (no overlap of 95% CI with control line) for the 3 tasks identified by red star

These findings suggest HCV-related impairment of cognitive function in the 3 domains of verbal memory, working memory, reasoning/problem solving.

 RESULTS

 

*No significant differences between HCV patients with fatigue vs. without fatigue on BAC composite scores (cognitive function) or CPT–IP (attention/vigilance).

*BAC composite scores of HCV patients lower than those of healthy controls.

*Disease stage (fibrosis) had no effect on BAC composite scores.

*Higher disease grade (liver inflammation) may be weakly associated with poorer cognitive function in patients with HCV.

Pearson correlation analysis of relationships between scores on 6 individual BAC tasks and: Level of Fatigue, Quality of Sleep:
 
Piper Fatigue Scale summary score (level of fatigue): No correlation with scores on any BAC cognitive task.

Sleep Quality Item: Poor sleep quality (high scores) was significantly correlated with impairment on three BAC tasks: Digit Sequencing, Symbol Coding, and Tower of London.

Examples below shows Pearson correlation analyses for symbol coding:

Conclusions
Findings of this study support previous reports of cognitive processing difficulty in patients with CHC. Differences in cognitive processing between CHC patients with vs. without fatigue at baseline were not significant in this sample, but merit further study in a larger sample.

Acknowledgements
This study was supported by a research grant from the National Institute of Nursing Research (NIH/NINR: 1 R15 NR 008794-01A1, Bailey, PI) and by a small grant from the Duke University School of Nursing Office of Research Affairs (Bailey, PI).