The prevalence of probable neuropathic pain in the US: results from a multimodal general-population health survey

Figures & data

Table 1 Demographic characteristics of the study sample (n=24,925)

Demographic characteristic		Unweighted		Weighted
		n	%	n	%
Sex	Male	11,925	47.8	116,560,000	48.2
	Female	13,000	52.2	125,270,000	51.8
Age, years	18–34	5,400	21.7	72,514,917	30
	35–44	3,402	13.6	39,698,557	16.4
	45–54	4,267	17.1	42,656,469	17.6
	55–64	4,473	17.9	40,556,004	16.8
	65–74	5,425	21.8	27,363,123	11.3
	75+	1,958	7.9	19,040,479	7.9
Race	White	7,417	29.8	156,760,000	64.8
	Hispanic	5,858	23.5	37,577,888	15.5
	Black	6,453	25.9	28,381,681	11.7
	Other	5,197	20.9	19,113,108	7.9
Questionnaire modality	Internet	15,088	60.5	139,460,000	57.7
	Telephone	2,907	11.7	36,672,669	15.2
	Mail	982	4	14,568,067	6
	Mall intercept	5,338	21.4	39,342,717	16.3
	Store-receipt invitation*	590	2.4	11,406,801	4.7
Region**	East	4,554	18.3	44,367,561	18.4
	Midwest	5,218	20.9	58,095,899	24
	South	8,820	35.4	80,982,310	33.5
	West	6,286	25.2	57,837,823	23.9

Notes:

* Store-receipt invitation refers to a method by which respondents were invited to participate through an Internet link on a store receipt that they received at participating retailers (eg, pharmacies, grocery stores);

** State and thus region information was unavailable for 47 respondents.

Figure 1 Study flowchart.

Notes: *Weighted data represent the frequency of the sample data after applying sampling weights, which were calculated by incorporating the age, sex, and race/ethnicity of the respondents. The US population is based on the most recent Current Population Survey (June 2015) conducted by the US Census Bureau. **Based on the self-reported question, “Have you experienced any physical pain in the last 12 months?” Patients who responded “Yes” were categorized as having pain for this study. Uppercase N refers to the US population, while lowercase n refers to the sample.
Abbreviation: NeP, neuropathic pain.

Figure 2 Distribution of PainDetect scores among those with pain (n=15,749).

Notes: Higher scores indicate increased likelihood of neuropathic pain. Respondents who did not self-report experiencing any pain in the past 12 months did not complete the PainDetect (n=9,174). Two respondents with pain in the past 12 months did not complete the PainDetect, and were not included in the PainDetect analyses.

Figure 3 Heat map of the weighted prevalence of probable neuropathic pain, based on the PainDetect, among those with pain by demographic strata.

Table 2 Prevalence of NeP based on the PainDetect among all respondents and all respondents with pain by survey modality

Modality	Among all adults (%)		Among all adults with any pain (%)
	Mean	95% CI	Mean	95% CI
Internet	10.8	(10.3–11.3)	17.2	(16.5–18)
Mail	8.7	(7.2–10.8)	11.3	(9.3–13.8)
Mall intercept	12.4	(11.5–13.3)	15.3	(14.3–16.4)
Store receipt	8.6	(6.6–11.2)	12.2	(9.4–15.7)
Telephone	4.1	(3.4–4.8)	15.4	(13.1–18.1)

Notes: Prevalence was estimated using a sample-weighted generalized linear model, controlling for age, sex, and race/ethnicity, and specifying a binomial distribution; models controlled for age, sex, and race/ethnicity, since different modalities were used to attract different demographic strata.

Abbreviations: NeP, neuropathic pain; CI, confidence interval.

Figure 4 Weighted comorbidity-prevalence estimates among respondents with probable NeP and respondents with pain but unlikely NeP.

Notes: Error bars indicate 95% confidence intervals.
Abbreviations: COPD, chronic obstructive pulmonary disease; GERD, gastroesophageal reflux disease; IBS, irritable bowel syndrome; MS, multiple sclerosis; NeP, neuropathic pain; RLS, restless leg syndrome; RA, rheumatoid arthritis; TIA, transient ischemic attack.

Table 3 Weighted demographic characteristics among respondents with probable NeP and respondents with pain but unlikely NeP

Demographic characteristics	Unlikely NeP (PainDetect <19)		Probable NeP (PainDetect ≥19)
	N=129,913,774		N=24,206,788
	n	% (95% CI)	n	% (95% CI)
Sex (%)
Male	61,765,757	47.6 (46.4–48.8)	12,013,398	49.6 (46.9–52.3)
Female	68,148,016	52.5 (51.3–53.7)	12,193,390	50.4 (47.7–53.1)
Age, years (%)
18–34	41,137,388	31.7 (30.5–32.9)	8,177,056	33.8 (31.1–36.5)
35–44	20,038,205	15.4 (14.6–16.2)	5,277,625	21.8 (19.7–23.9)
45–54	22,899,740	17.6 (16.7–18.5)	4,947,003	20.4 (18.3–22.5)
55–64	22,374,378	17.2 (16.4–18)	3,481,001	14.4 (12.7–16.1)
65–74	15,019,395	11.6 (11–12)	1,524,141	6.3 (5.4–7.2)
75+	8,444,667	6.5 (5.7–7.3)	799,963	3.3 (2.5–4.1)
Race/ethnicity (%)
White	84,905,188	65.4 (64.5–66.3)	13,566,229	56 (57.1–54.9)
Hispanic	19,994,555	15.4 (14.8–16)	5,442,441	22.5 (21.1–23.9)
Black	14,940,179	11.5 (11–12)	3,372,573	13.9 (12.6–15.2)
Other	10,073,852	6.5 (6.7–7.9)	1,825,545	7.5 (6.2–8.8)
Region (%)
Northeast	23,337,766	18 (17.1–18.9)	4,964,442	20.5 (18.4–22.6)
Midwest	34,302,737	26.4 (25.3–27.5)	4,943,089	20.4 (18.2–22.6)
South	41,166,584	31.7 (30.6–32.8)	8,393,247	34.7 (32.2–37.2)
West	30,772,373	23.7 (22.7–24.7)	5,859,445	24.2 (21.9–26.5)

Note: Column percentages are reported, which provides the percentage of respondents in each row who have probable NeP and unlikely NeP.

Abbreviations: NeP, neuropathic pain; CI, confidence interval.

Figure 5 Weighted pain-type prevalence among respondents with probable NeP and respondents with pain but unlikely NeP.

Notes: Percentage based on those who self-reported having diabetes. Error bars indicate 95% confidence intervals. All pain types were significantly different between groups, with the exception of “Other” (P=0.062).
Abbreviation: NeP, neuropathic pain.

Table 4 Respondents’ duration of pain by pain type

Pain type		Probable NeP (PainDetect ≥19)
		<1 year	1–<5years	5+ years
		N=24,206,788
Arthritis/joint pain	n	1,880,793	4,350,453	5,315,768
	%	16.29%	37.68%	46.04%
Back pain	n	2,967,346	6,073,593	7,808,091
	%	17.61%	36.05%	46.34%
Dental/facial pain	n	2,404,032	1,565,175	1,172,127
	%	46.76%	30.44%	22.8%
Headache/migraine	n	1,687,695	2,697,547	4,576,751
	%	18.83%	30.1%	51.07%
Diabetes-related pain	n	384,435	901,935	832,384
	%	18.14%	42.57%	39.29%
Pelvic pain	n	1,403,749	1,873,945	1,566,012
	%	28.98%	38.69%	32.33%
Spinal cord injury	n	464,685	690,022	978,399
	%	21.78%	32.35%	45.87%
Shingles	n	432,924	405,714	240,809
	%	40.11%	37.59%	22.31%
Surgical	n	1,303,247	927,156	762,799
	%	43.54%	30.98%	25.48%
Trauma pain	n	918,365	922,028	1,890,530
	%	24.61%	24.71%	50.67%
Other	n	483,577	852,812	1,497,146
	%	17.07%	30.1%	52.84%

Abbreviation: NeP, neuropathic pain.

Table 5 Current NeP-medication use by respondents who self-reported experiencing nerve pain for at least 3 months

NeP-medication	All respondents self-reporting nerve pain			Probable NeP respondents self-reporting nerve pain
	N=79,876,938			N=20,953,636
	n	%	95% CI	n	%	95% CI
NSAID	38,342,532	48	46.5–49.5	8,738,205	41.7	38.9–44.5
Weak opioid	25,634,060	32.1	30.7–33.4	9,035,284	43.1	40.3–46
Antiepileptic	9,173,723	11.5	10.5–12.4	4,238,701	20.2	17.9–22.5
Strong opioid	8,890,192	11.1	10.2–12.1	4,369,720	20.9	18.5–23.2
Muscle relaxant	7,955,673	10	9.1–10.9	4,141,427	19.7	17.4–22.1
Tramadol	5,356,325	6.7	6–7.4	2,440,161	11.6	9.8–13.5
SSRI	5,062,934	6.3	5.6–7.1	2,603,209	12.4	10.4–14.4
TCA	2,640,531	3.3	2.8–3.8	1,594,214	7.6	6.1–9.2
SNRI	2,725,170	3.4	2.9–4	1,584,318	7.6	6–9.1
COX2 inhibitor	2,293,024	2.9	2.4–3.3	1,012,713	4.8	3.6–6
Benzodiazepine	2,216,143	2.8	2.3–3.3	1,284,562	6.1	4.7–7.6
Local anesthetic	1,303,814	1.6	1.2–2	560,863	2.7	1.8–3.6
NMDA-receptor antagonist	330,978	0.4	0.2–0.6	185,745	0.9	0.3–1.4
Other	3,926,884	5	4.3–5.6	631,249	3	2–4

Abbreviations: NeP, neuropathic pain; CI, confidence interval; NSAID, nonsteroidal anti-inflammatory drug; SSRI, selective serotonin-reuptake inhibitor; TCA, tricyclic antidepressant; SNRI, serotonin–norepinephrine reuptake inhibitor; NMDA, N-methyl-d-aspartate.

Table S1 Medications participants reported for nerve pain, categorized by class

Class	Medication
Antiepileptics	Carbamazepine
	Lamotrigine
	Pregabalin
	Topiramate
	Zonisamide
Benzodiazepine	Diazepam
COX2	Celecoxib
GABA	Baclofen
	Gabapentin
Local anesthetics	Lidocaine
Muscle relaxants	Metaxalone
	Carisoprodol
	Cyclobenzaprine
	Methocarbamol
	Tizanidine
NMDA-receptor antagonists	Ketamine
NSAIDs	Diclofenac
	Ibuprofen
	Meloxicam
	Naproxen
	Nabumetone
Other	Other
SNRIs	Duloxetine hydrochloride
	Milnacipran hydrochloride
	Venlafaxine
	Citalopram
	Escitalopram
	Fluoxetine
	Paroxetine
	Sertraline
Strong opioids	Fentanyl
	Hydromorphone hydrochloride
	Methadone
	Morphine
	Oxycodone
TCAs	Amitriptyline HCl
	Desipramine
	Imipramine
Tramadol	Tramadol
Weak opioids	Acetaminophen with codeine
	Codeine
	Hydrocodone
	Hydrocodone bitartrate/ibuprofen
	Hydrocodone with acetaminophen
	Hydrocodone with aspirin
	Tramadol/acetaminophen

Abbreviations: GABA, γ-aminobutyric acid; NMDA, N-methyl-d-aspartate; NSAIDs, nonsteroidal anti-inflammatory drugs; SNRIs, serotonin–norepinephrine reuptake inhibitors; SSRIs, selective serotonin-reuptake inhibitors; TCAs, tricyclic antidepressants.