Emotion Regulation and Psychological Dependence on Pain Medication among Hospital Outpatients with Chronic Spinal Pain: The Influence of Rumination about Pain and Alexithymia

Figures & data

Table 1. Descriptive statistics for study measures (n = 106).

Scale	Items	Mean	SD	Min–max	Alpha
Age (years)	1	56.57	14.74	23–88	–
Pain duration (months)	1	85.55	109.12	4–492	–
Pain intensity	1	7.41	1.70	3–10	–
DASS-21
Depression	7	11.57	11.65	0–42	0.94
Anxiety	7	9.89	8.72	0–32	0.82
Stress	7	14.57	1.12	0–42	0.91
CPAQ-8
Activity engagement	4	13.64	6.15	0–24	0.85
Pain willingness	4	6.49	5.53	0–24	0.80
Pain acceptance total	8	20.13	7.35	4–40	0.79
PCS
Rumination	4	7.89	5.26	0–16	0.93
Magnification	3	5.30	3.35	0–12	0.73
Helplessness	6	11.44	7.08	0–24	0.92
Catastrophising total	13	24.63	14.86	0–52	0.96
TAS-20
Difficulty describing feelings	5	12.49	4.79	5–25	0.68
Difficulty identifying feelings	7	17.40	7.36	7–34	0.89
Externally oriented thinking	8	21.16	4.15	8–31	0.63
Alexithymia total	20	51.05	12.97	24–81	0.88
LDQ
Pain medication dependence	10	11.52	7.35	0–30	0.88

Notes: DASS-21 = Depression, Anxiety and Stress Scale-21; CPAQ-8= Chronic Pain Acceptance Questionnaire-8; PCS = Pain Catastrophising Scale; TAS-20= Toronto Alexithymia Scale-20; LDQ = Leeds Dependence Questionnaire; Alpha = Cronbach’s alpha coefficient.

Table 2. Correlations among predictor variables in the linear regression analyses (n = 106).

1. Pain intensity	1.0
2. Depression	0.29**	1.0
3. Anxiety	0.37***	0.76***	1.0
4. Stress	0.32**	0.73***	0.75***	1.0
5. Activity engagement	−0.31**	−0.21*	−0.16	−0.30**	1.0
6. Pain willingness	−0.34***	−0.01	−0.11	−0.11	−0.21*	1.0
7. Rumination	0.52***	0.59***	0.56***	0.52***	−0.26**	−0.34	1.0
8. Magnification	0.44***	0.51***	0.40***	0.46***	−0.26**	−0.39***	0.78***	1.0
9. Helplessness	0.54***	0.52***	0.55***	0.52***	−0.34***	−0.39***	0.88***	0.81***	1.0
10. Difficulty describing feelings	0.17	0.60***	0.50***	0.46***	−0.06	−0.08	0.37***	0.32***	0.33**
11. Difficulty identifying feelings	0.38***	0.57***	0.53***	0.57***	−0.12	−0.41***	0.57***	0.56***	0.57***
12. Externally oriented thinking	0.03	0.26**	0.16	−0.02	−0.15	0.15	0.14	0.11	0.09
13. Pain medication dependence (LDQ)	0.53***	0.51***	0.54***	0.52**	−0.24*	−0.31**	0.61***	0.54***	0.58***
	1	2	3	4	5	6	7	8	9

Table 2 continued

10. Difficulty describing feelings	1.0
11. Difficulty identifying feelings	0.72***	1.0
12. Externally oriented thinking	0.34***	0.16	1.0
13. Pain medication dependence (LDQ)	0.33***	0.54***	0.03
	10	11	12

Notes: LDQ = Leeds Dependence Questionnaire.

*p < = 0.05; **p < = 0.01; ***p < = 0.001.

Table 3. Summary of hierarchical multiple linear regression analysis to predict degree of pain medication dependence (n = 106).

Predictor variable	Block 1		Block 2
Block 1	β	P	β	p
Disabled by spinal pain	0.355	<0.001	0.302	<0.001
Spinal pain intensity	0.313	<0.001	0.165	0.045
Borrowed pain medication	0.209	0.006	0.174	0.008
Emergency phone call or clinic visit	0.169	0.029	0.107	0.120
Block 2
Difficulty Identifying Feelings			0.249	0.002
Rumination			0.193	0.030
Pain intensity x Rumination			0.192	0.004
R^2	0.452	–	0.614	–
ΔR^2	0.452	<0.001	0.162	<0.001

Notes: The table shows Beta weights (standardized regression coefficients) and p values for predictor variables that were retained in the final regression models. Dependent variable = pain medication dependence (Leeds Dependence Questionnaire score); R² = proportions of variance accounted for; ΔR² = change in R². The regression analysis was structured hierarchically with predictor variables added to the model in two blocks: 1) demographic and clinical factors, medication use and risk behaviors for medication misuse that were significantly associated with dependence in the bivariate analyses; 2) psychological factors and terms for the interactions between those factors and pain intensity. Variables were added to the model using the stepwise method in each block. The criteria for entry and removal were p < 0.05 and p > 0.10 respectively. Only predictor variables that were retained in the final models of each block are shown in the table (a full listing of Beta weights and p values for all predictor variables including those not retained in the final models of each block is given in Table S1, Supplementary Material).

Figure 1. Effects of pain intensity and rumination on degree of pain medication dependence (LDQ scores across the range).

Note: LDQ = Leeds Dependence Questionnaire

Table 4. Summary of multiple logistic regression analysis to predict severe pain medication dependence (n = 106).

Predictor variable	B	S.E.	Wald	df	Sig.	Odds ratio (95% CIs)
Block 1
Spinal pain intensity	1.049	0.308	11.623	1	0.001	2.855 (1.562–5.219)
Borrowed medication	3.024	1.057	8.187	1	0.004	20.579 (2.593–163.346)
Block 2
Spinal pain intensity	0.699	0.340	4.223	1	0.040	2.012 (1.033–3.919)
Borrowed medication	2.798	1.154	5.883	1	0.015	16.418 (1.711–157.550)
Pain intensity x high alexithymia	1.983	0.763	6.746	1	0.009	7.261 (1.627–32.416)

Notes: Dependent variable = severe pain medication dependence (LDQ score < 20 vs ≥ 20); B = Unstandardized regression coefficient. S.E. = Standard error of B. Wald = Wald statistic. Sig = probability. CI = confidence interval. Predictor variables with significant bivariate associations with the dependent variable were added to the model using the forward conditional method. Only predictor variables that were retained in each model are shown in the table.

Figure 2. Percentages of participants with severe pain medication dependence (LDQ scores ≥ 20).

Note: LDQ = Leeds Dependence Questionnaire