Comparison of pain, functioning, coping, and psychological distress in patients with chronic low back pain evaluated for spinal cord stimulator implant or behavioral pain management.

OBJECTIVE: Subgroups of patients with chronic low back pain may exhibit differences in self-reported measures of pain, functioning, coping, and psychological distress. The present study compared subgroups of patients with chronic low back pain referred either for pre-spinal cord stimulator (SCS) psychological evaluations or for behavioral pain management (BPM). DESIGN: Measures from comprehensive pain, functioning, and psychological assessments were compared using multivariate ancova. SETTING: Tertiary care medical outpatient pain management center. SUBJECTS: One hundred and two patients (64% female, mean age = 53.7, standard deviation = 14.3) with chronic low back pain diagnoses were evaluated either as possible candidates for SCS (N = 73) or as part of treatment planning for BPM (N = 29). METHODS: These groups were compared on measures of pain, interference, disability, pain-related anxiety, pain coping, pain catastrophizing, depression, post-traumatic stress symptoms, affective distress, and interpersonal distress assessed using standardized scales. It was hypothesized that the two groups would report similar levels of pain, functioning, and coping, but pre-SCS patients would report fewer psychological symptoms of psychological distress compared with BPM patients in order to gain approval for SCS. RESULTS: Consistent with hypotheses, BPM and pre-SCS patients reported similar pain, functioning, and coping, but pre-SCS patients reported fewer psychological symptoms. CONCLUSIONS: Pre-SCS patients possibly underreport psychological symptoms perhaps to gain SCS approval for SCS. Separate norms and cutoffs for pre-SCS psychological evaluations may be needed to better identify risks of unsuccessful outcomes. Validity scales for measures of psychological distress also could be developed to detect biased reporting. Alternatively, referring clinicians may have referred patients for BPM who were more psychologically distressed and perceived as more in need of psychosocial intervention than those referred for pre-SCS evaluations. Further investigation of clinical referral decisions and assessment bias is warranted to clarify the meaning of these differences and how they apply to patient outcomes.

Personality correlates of adherence with continuous positive airway pressure (CPAP).

INTRODUCTION: Adherence with continuous positive airway pressure (CPAP) for obstructive sleep apnea (OSA) has been problematic. Understanding the factors associated with nonadherence may assist with psychosocial interventions. OBJECTIVE: The objective of this study was to examine the relationship between adherence and three measures of personality and coping strategies. METHODS: Ratings on the behavioral inhibition system/behavioral activation system (BIS/BAS) scales, the ways of coping inventory, and a broad personality measure (mini-IPIP) were analyzed with a binary logistic regression among 63 subjects, adult men (31) and women (32), diagnosed with OSA. Data from the CPAP device was obtained following initial 30 days at minimum, with adherence defined as >4 h/night on 70% of nights. RESULTS: Elevated BIS was the strongest predictor of nonadherence (r = -.452, p < .01), followed by neuroticism. The regression correctly classified 73% of participants as adherent or nonadherent. CONCLUSION: Nonadherence is associated with elevated BIS scores and neuroticism, which indicates that personality factors play a role in determining adherence to CPAP. Although more research is needed to draw firm conclusions, the differences noted in BIS may also point toward differences in neurophysiological function. The BIS scale may be a useful tool for predicting nonadherence and assist with the development of intervention strategies that will increase adherence.