Neuropathic sensory symptoms: association with pain and psychological factors

Figures & data

Table 1 Demographic and clinical characteristics of patients (results of one-way ANOVA, post hoc Tukey’s tests, and chi-squared test)

Characteristic	TNP n=78	RAD n=68	FM n=61	nBP n=99	F(df) or χ^2(df)	Tukey’s test (P<0.05)
Age (M ± SD)	61.05±12.8	59.5±13.6	54.78±10.1	60.3±14.3	F(3, 302)=3.08*	FM < TNP
Sex, n (%)
Female	47.4%	64.8%	82.5%	67.7%	χ^2(3)=18.40***	–
Pain history (years)	7.6±5.1	7.3±5.6	9.5±6.5	8.9±8	F(3, 305)=1.75†	–
NRS (M ± SD)	6.63±1.9	6.83±1.7	6.91±1.6	6.63±2.0	F(3, 300)=0.47†	–
MPSS (M ± SD)	8.72±1.1	8.92±1.3	9.28±1.1	8.45±1.1	F(3, 288)=6.11***	nBP, TNP < FM
PDQ (M ± SD)	19.01±7.2	20.32±6.5	19.50±6.9	13.27±6.6	F(3, 299)=19.42***	nBP < RAD, TNP, FM
PCS-H (M ± SD)	12.06±5.2	10.93±5.7	13.63±4.9	12.33±5.2	F(3, 231)=1.84†	–
CPAQ (M ± SD)	32.93±10.1	32.06±9.9	27.41±10.8	29.64±9.6	F(3, 227)=2.46†	–
ADS-K (M ± SD)	15.63±8.9	14.52±9.6	21.93±10.1	17.34±8.8	F(3, 230)=4.64**	RAD, TNP < FM

Notes:

*** P<0.001;

** P<0.01;

* P<0.05;

† Not significant.

Abbreviations: ADS-K, Allgemeine Depressions Skala–Kurz version; ANOVA, analysis of variance; CPAQ, Chronic Pain Acceptance Questionnaire; df, degrees of freedom; FM, fibromyalgia; M, mean; MPSS, Mainz Pain Staging System; nBP, nociceptive back pain; NRS, Numeric Rating Scale; PCS-H, Pain Catastrophizing Scale–Helplessness; PDQ, Pain DETECT Questionnaire; RAD, radiculopathy; SD, standard deviation; TNP, typical neuropathic pain.

Table 2 Multinominal logistic regression analysis: odds ratio, 95% confidence intervals, significance, and pseudo R²

Level of self-reported neuropathic sensory symptoms	Diagnostic group (Ref = typical neuropathic pain)
	RAD	FM	nBP	Pseudo R^2
Moderate level (M=2.51)a	1.06 (0.37–3.05)†	0.90 (0.30–2.70)†	0.24 (0.10–0.55)**
High level (M=3.36)a	0.86 (0.28–2.64)†	1.18 (0.38–3.68)†	0.05 (0.01–0.16)***	0.19***
Ref: Low level (M=1.38)a

Notes:

a Mean score of the self-reported neuropathic sensory symptoms (sum of the seven sensory symptoms/7);

*** P<0.001;

** P<0.01;

† Not significant.

Abbreviations: FM, fibromyalgia; M, mean; nBP, nociceptive back pain; RAD, radiculopathy; Ref, reference.

Table 3 Means and SDs of various pain and psychological variables in patients with different levels of self-reported neuropathic sensory symptoms across the four diagnostic groups (clustering 1)

		“Cluster 1” Low level of neuropathic sensory symptoms (M=1.38)a	“Cluster 2” Moderate level of neuropathic sensory symptoms (M=2.51)a	“Cluster 3” High level of neuropathic sensory symptoms (M=3.36)a	F(df)	Post hoc “LSD”
TNP	NRS (M ± SD)	5.87±2.85	6.41±1.75	6.96±1.92	1.15 (2, 70)†	–
	MPSS (M ± SD)	8.25±1.48	8.73±1.05	8.77±1.18	0.68 (2, 70)†	–
	PCS-H (M ± SD)	11.50±2.00	12.86±5.70	10.46±5.70	0.88 (2, 40)†	–
	CPAQ (M ± SD)	33.80±10.29	33.95±10.21	32.64±11.18	0.07 (2, 37)†	–
	ADS-K (M ± SD)	15.00±1.41	16.72±9.72	15.21±10.41	0.16 (2, 40)†	–
RAD	NRS (M ± SD)	6.62±1.59	6.68±1.77	7.20±1.47	0.69 (2, 63)†	–
	MPSS (M ± SD)	8.42±0.97	8.89±1.44	9.26±1.32	1.03 (2, 61)†	–
	PCS-H (M ± SD)	9.33±3.82	10.80±5.71	12.23±6.21	0.66 (2, 55)†	–
	CPAQ (M ± SD)	37.66±12.45	33.17±9.30	27.58±10.11	2.93 (2, 55)†	–
	ADS-K (M ± SD)	14.20±4.65	12.82±9.33	18.94±10.59	2.39 (2, 54)†	–
FM	NRS (M ± SD)	6.28±1.60	6.53±1.66	7.50±1.44	3.03 (2, 55)†	–
	MPSS (M ± SD)	9.28±0.75	8.92±1.23	9.70±1.08	3.04 (2, 55)†	–
	PCS-H (M ± SD)	10.80±2.16	13.40±5.47	16.37±4.71	2.11 (2, 25)†	–
	CPAQ (M ± SD)	31.40±11.80	27.60±10.97	26.14±11.52	0.33 (2, 24)†	–
	ADS-K (M ± SD)	17.60±10.26	20.53±9.54	26.12±10.93	1.28 (2, 25)†	–
nBP	NRS (M ± SD)	6.06±1.82	6.89±2.12	8.00±2.23	3.76 (2, 95)*	1 < 3
	MPSS (M ± SD)	8.33±1.16	8.42±1.05	9.14±1.06	1.60 (2, 86)†	–
	PCS-H (M ± SD)	11.04±5.99	12.93±4.28	16.00±4.20	3.50 (2, 95)*	1 < 3
	CPAQ (M ± SD)	32.75±11.47	27.91±6.85	23.14±7.58	5.00 (2, 95)**	(2, 3) < 1
	ADS-K (M ± SD)	15.29±8.53	17.61±7.79	25.85±10.63	4.97 (2, 95)**	(1, 2) < 3
Total	NRS (M ± SD)	6.19±1.93	6.65±1.86	7.25±1.68	6.09 (2, 293)**	(1, 2) < 3
	MPSS (M ± SD)	8.44±1.15	8.72±1.21	9.22±1.22	7.76 (2, 281)***	(1, 2) < 3
	PCS-H (M ± SD)	10.96±5.18	12.35±5.19	13.02±5.93	2.22 (2, 224)†	–
	CPAQ (M ± SD)	33.26±10.91	30.50±9.15	28.06±10.60	3.57 (2, 220)*	3 < 1
	ADS-K (M ± SD)	15.38±7.77	16.41±9.11	20.17±11.27	3.82 (2, 223)*	(1, 2) < 3

Notes:

a Mean score of the self-reported neuropathic sensory symptoms (sum of the 7 sensory symptoms/7);

*** P<0.001;

** P<0.01;

* P<0.05;

† Not significant.

Abbreviations: ADS-K, Allgemeine Depressions Skala–Kurz version; CPAQ, Chronic Pain Acceptance Questionnaire; df, degrees of freedom; FM, fibromyalgia; LSD, Fisher’s least significant difference; M, mean; MPSS, Mainz Pain Staging System; nBP, nociceptive back pain; NRS, Numeric Rating Scale; PCS-H, Pain Catastrophizing Scale–Helplessness; RAD, radiculopathy; SD, standard deviation; TNP, typical neuropathic pain.

Figure 1 Subgroups of chronic pain patients with distinct patterns of neuropathic sensory symptoms using the Pain DETECT Questionnaire (clustering 2).

Note: Vertical axis: adjusted scores of neuropathic sensory symptoms; horizontal axis marked as 0: average of seven adjusted scores of neuropathic sensory symptoms.
Abbreviations: ADS-K, Allgemeine Depressions Skala–Kurz version; CPAQ, Chronic Pain Acceptance Questionnaire; FM, fibromyalgia; MPSS, Mainz Pain Staging System; nBP, nociceptive back pain; NRS, Numeric Rating Scale; PCS-H, Pain Catastrophizing Scale–Helplessness; RAD, radiculopathy; TNP, typical neuropathic pain.