The objectives of this study were the following: to determine if
fatigue is present in chronic
low back pain (LBP) and chronic
neck pain patients to a greater extent than in controls (nonpatients); to determine which variables are associated with the presence of
fatigue; and to determine which of the above
chronic pain patient (
CPP) groups is more fatigued. To the authors' knowledge, this is the first such study in the literature.
DESIGN: Totals of 175 chronic LBP and 33 chronic
neck pain patients completed the Multidimensional
Fatigue Inventory (MFI),
Neuropathic Pain Scale (NPS), and Beck Depression Inventory rating scales on admission. In addition, an information tool was completed on each
CPP and contained the following information: demographics, primary and secondary
pain diagnoses, DSM-IV psychiatric diagnoses assigned,
pain location,
pain precipitating event, type of injury, years in
pain, number of surgeries, types of surgery, type of
pain pattern,
opioids consumed per day in
morphine equivalents, workers' compensation status, and whether, according to the clinical examination, the
pain did or did not have a neuropathic component. Scores on the MFI were then compared with published norms for controls (nonpatients) via chi-squared tests. Bivariate analyses were conducted between the MFI subscales and the variables selected for analysis. Pearson correlations, analyses of variance, and t-tests were used to test for relationships between MFI scale scores and the appropriate variables. In the next step of the analysis, stepwise regression analyses were used to predict each of the MFI subscale scores using the variables that were found to be significantly (P < 0.05) related to
fatigue by the preceding analysis. In the final analysis, the variables that were significant predictors of the
fatigue subscales were controlled for as covariates in an analysis of variance in order to determine if chronic LBP patients had scores on the MFI subscales that were significantly different from those of chronic
neck pain patients.
SETTING: Chronic LBP and chronic
neck pain patients were found to be significantly more fatigued than controls (nonpatients). Most of the MFI subscale scores could be predicted by four major variables: presence of
neuropathic pain, female gender, presence of depression, and total number of DSM-IV diagnoses. Chronic LBP patients were as fatigued as chronic
neck pain patients.
CONCLUSIONS: The complaint of
fatigue appears to be a significant problem for chronic LBP and chronic
neck pain patients. This complaint may be associated with
neuropathic pain, female gender, and psychiatric comorbidities.