Pain Prevalence and Chronicity in a Developing Country in Latin America: a Population-Based Survey in Lima, Peru

Figures & data

Table 1. Sociodemographic characteristics of study participants.

Characteristics	Total: n	Pain		p-value^†
		No: n (%)	Yes: n (%)
Sex				0.089
Male	249	96 (38.7)	153 (61.3)
Female	253	78 (30.9)	175 (69.1)
Age, years				< 0.001^‡
Median (IQR)	38.0 (27.0–50.0)	32.0 (24.0–42.6)	41.0 (30.0–53.0)
Age group, years				< 0.001
18–40	282	121 (43.0)	161 (57.0)
41–60	162	40 (24.6)	122 (75.4)
61+	58	13 (22.8)	44 (77.2)
Marital status				0.7
Single	210	77 (36.6)	133 (63.4)
Married/cohabiting	250	85 (34.0)	165 (66.0)
Divorced/separated/widowed	41	12 (30.3)	29 (69.7)
Missing data	1	0	1
Educational level				0.2
No study/primary	19	2 (11.5)	17 (88.5)
High school	209	72 (34.6)	137 (65.4)
Technical superior	124	46 (37.2)	78 (62.8)
University superior	150	54 (35.9)	96 (64.1)
Occupational status				< 0.001
Full time work	272	106 (38.9)	166 (61.1)
Homeworker	107	34 (31.4)	73 (68.6)
Unemployed	32	6 (19.4)	25 (80.6)
Student	37	21 (56.8)	16 (43.2)
Part-time work	54	8 (14.2)	46 (85.8)
Health insurance				0.4
Comprehensive health insurance	171	59 (34.4)	112 (65.6)
Social health security	146	50 (33.9)	97 (66.1)
Armed forces and police health insurance	18	10 (59.1)	7 (40.9)
Private health insurance	40	12 (28.9)	28 (71.1)
No insurance	123	41 (33.0)	83 (67.0)
Missing data	3	3	0
Socioeconomic level				0.4
A/B (richest level)	95	36 (37.3)	60 (62.7)
C	281	102 (36.4)	179 (63.6)
D	113	35 (30.4)	79 (69.6)
E (poorest level)	11	2 (16.9)	9 (83.1)
Lima sector				0.009
North	130	29 (22.6)	101 (77.4)
East	122	43 (35.3)	79 (64.7)
South	96	48 (50.2)	48 (49.8)
Residential Lima	57	16 (27.3)	42 (72.7)
Central Lima	96	38 (39.4)	58 (60.6)

† Unless otherwise stated, χ-square test with Rao and Scott second-order correction.

‡ Wilcoxon signed-rank test for complex samples.

n: Observations estimated by weighting real observations so that sums could differ up to ± 1 due to approximation error; %: column-weighted percentage.

IQR: Interquartile range.

Figure 1. Distribution of the prevalence of pain according to the body site and type.

Table 2. Characteristics of the pain of greatest concern in the population who reported having pain in the last 3 months.

Pain history	Total		Sex
	n (%)	95% CI	Male: n (%)	Female: n (%)	p-value^†
Onset of pain					0.2
<1 week	29 (9.2%)	5.82–14.1%	9 (6.0%)	20 (11.8%)
2–4 weeks	38 (11.8%)	8.29–16.6%	14 (9.5%)	24 (13.8%)
1–3 months	58 (18.3%)	14.1–23.3%	25 (17.1%)	33 (19.3%)
>3 months	193 (60.8%)	54.6–66.6%	99 (67.4%)	94 (55.1%)
Missing data	10		7	3
Type of pain					0.046
Acute (≤3 months)	125 (39.2%)	33.4–45.4%	48 (32.6%)	77 (44.9%)
Chronic (>3 months)	193 (60.8%)	54.6–66.6%	99 (67.4%)	94 (55.1%)
Missing data	10		7	3
Initial intensity of pain in NRS					0.040^‡
Median (IQR)	5.0 (4.0–8.0)		5.0 (4.0–8.0)	6.0 (4.0–8.0)
Range	0.0–10.0		0.0–10.0	1.0–10.0
Initial intensity level of pain					0.4
Mild (NRS 1–3)	63 (19.4%)	13.6–26.8%	33 (21.8%)	30 (17.2%)
Moderate (NRS 4–6)	138 (42.1%)	35.6–48.8%	66 (43.2%)	72 (41.1%)
Severe (NRS 7–10)	126 (38.6%)	31.8–45.8%	53 (35.0%)	73 (41.7%)
Pain frequency					0.4
Intermittent	54 (16.7%)	12.2–22.4%	21 (13.7%)	34 (19.3%)
Sporadic	139 (42.6%)	37.4–48.1%	73 (47.8%)	66 (38.1%)
Frequent	98 (30.1%)	24.4–36.4%	44 (28.8%)	54 (31.2%)
Constant	35 (10.6%)	6.99–15.7%	15 (9.7%)	20 (11.4%)
Missing data	1		0	1

† Unless otherwise stated, χ-square test with Rao and Scott second-order correction.

‡ Wilcoxon signed-rank test for complex samples.

n: Observations estimated by weighting real observations so that sums can differ up to ± 1 due to approximation error; %: column-weighted percentage.

IQR: Interquartile range; NRS: Numerical rating scale.

Table 3. Type of the pain of greatest concern in the population who reported having pain in the last 3 months.

Characteristics	Type of pain^†		p-value^‡
	Acute (<3 months): n (%)	Chronic (≥3 months): n (%)
Sex			0.046
Male	48 (38.2)	99 (51.1)
Female	77 (61.8)	94 (48.9)
Age, years			0.009^§
Median (IQR)	36.3 (26.8–50.0)	42.0 (32.0–54.0)
Range	18.0–70.0	18.0–70.0
Age group, years			0.2
18–40	70 (56.0)	90 (46.9)
41–60	42 (33.5)	71 (36.9)
61+	13 (10.6)	31 (16.2)
Marital status			> 0.9
Single	51 (41.4)	77 (40.0)
Married/cohabiting	62 (50.0)	98 (50.6)
Divorced/separated/widowed	11 (8.6)	18 (9.3)
Missing data	1	0
Educational level			0.5
No study/primary	7 (5.9)	8 (4.4)
High school	47 (37.7)	86 (44.5)
Technical superior	28 (22.9)	46 (24.0)
University superior	42 (33.6)	52 (27.1)
Occupational status			> 0.9
Full-time work	61 (49.1)	98 (50.8)
Homeworker	28 (22.7)	42 (22.0)
Unemployed	9 (7.5)	16 (8.3)
Student	5 (4.4)	10 (5.4)
Part-time work	20 (16.3)	26 (13.5)
Health insurance			0.6
Comprehensive health insurance	48 (38.8)	61 (31.7)
Social health security	37 (29.4)	58 (29.8)
Armed forces and police health insurance	2 (1.7)	5 (2.4)
Private health insurance	12 (9.3)	17 (8.6)
No insurance	26 (20.8)	53 (27.6)
Lima sector			0.2
North	40 (32.3)	57 (29.3)
East	22 (17.6)	54 (28.0)
South	16 (13.1)	32 (16.4)
Residential Lima	18 (14.6)	23 (11.9)
Central Lima	28 (22.4)	28 (14.4)
Socioeconomic level			0.6
A/B (richest level)	28 (22.1)	30 (15.5)
C	64 (51.1)	112 (58.3)
D	31 (24.5)	44 (22.8)
E (poorest level)	3 (2.3)	7 (3.4)
Pain frequency			< 0.001
Intermittent	34 (27.4)	20 (10.6)
Sporadic	59 (47.2)	76 (39.6)
Frequent	20 (16.1)	73 (38.3)
Constant	12 (9.3)	22 (11.5)
Missing data	0	1
Initial intensity level of pain			0.5
Mild (NRS 1–3)	24 (19.5)	35 (18.3)
Moderate (NRS 4–6)	58 (46.6)	78 (40.3)
Severe (NRS 7–10)	42 (33.9)	80 (41.4)
Type of drug treatment received			0.4
No medication	48 (38.6)	65 (33.6)
Only NSAID	49 (38.9)	77 (39.8)
Only weak opioid	1 (0.5)	4 (2.0)
NSAID + weak opioid	0 (0.0)	5 (2.5)
Other drugs, no NSAID neither opioid	27 (22.0)	43 (22.1)

† 11 participants (weighted n = 10) did not provide data to determine chronicity of pain.

‡ Unless otherwise stated, χ-square test with Rao and Scott second-order correction.

§ Wilcoxon signed-rank test for complex samples.

n: Observations estimated by weighting real observations so that sums could differ up to ± 1 due to approximation error; %: column-weighted percentage.

IQR: Interquartile range; NRS: Numerical rating scale; NSAID: Non-steroidal anti-inflammatory drug.

Table 4. Relationship between quality of life level and pain characteristics in participants who had pain in the last 3 months.

Pain history of greatest concern	Quality of life level^†			p-value^‡
	0–5 (low): n (%)	6–7 (middle): n (%)	8–10 (high): n (%)
Have current pain	40 (24.9)	36 (22.2)	85 (52.9)	0.3
Number of body sites with pain				> 0.9
Only one	47 (21.6)	41 (18.9)	129 (59.5)
Only two	19 (23.1)	19 (23.3)	43 (53.7)
Three or more	6 (21.2)	7 (24.8)	14 (54.0)
Only have one body site with pain	47 (21.6)	41 (18.9)	129 (59.5)	0.6
Have the current pain of greatest concern	36 (25.7)	32 (22.9)	73 (51.4)	0.2
Type of pain				0.8
Acute (≤3 months)	30 (24.2)	25 (19.9)	69 (55.8)
Chronic (>3 months)	39 (20.4)	40 (21.2)	111 (58.4)
Missing data	2	1	6
Onset of pain				0.9
<1 week	7 (22.7)	7 (25.4)	15 (51.9)
2–4 weeks	11 (29.4)	5 (13.7)	21 (56.9)
1–3 months	12 (21.6%)	12 (21.2%)	33 (57.2%)
>3 months	39 (20.4)	40 (21.2)	111 (58.4)
Missing data	2	1	6
Initial intensity level of pain				0.005
Mild (NRS 1–3)	16 (25.5)	7 (10.8)	40 (63.7)
Moderate (NRS 4–6)	16 (12.1)	33 (24.3)	87 (63.6)
Severe (NRS 7–10)	38 (30.9)	26 (21.1)	60 (47.9)
Pain frequency				0.037
Intermittent	15 (28.6)	14 (26.3)	24 (45.1)
Sporadic	19 (13.7)	26 (18.7)	93 (67.6)
Frequent	23 (24.1)	22 (22.5)	51 (53.4)
Constant	13 (37.8)	5 (13.2)	17 (48.9)
Missing data	1	0	1
Current level of pain of greatest concern				0.3
Mild (NRS 1–3)	4 (24.8)	1 (6.0)	12 (69.2)
Moderate (NRS 4–6)	16 (25.3)	17 (26.4)	31 (48.3)
Severe (NRS 7–10)	16 (26.3)	15 (24.2)	30 (49.4)
Missing data	34	34	113

† Five participants had missing data in quality of life score.

‡ Unless otherwise stated, χ-square test with Rao and Scott second-order correction.

n: Observations estimated by weighting real observations so that sums could differ up to ± 1 due to approximation error; %: column-weighted percentage.

NRS: Numerical rating scale.

Table 5. Comparison of management of pain of greatest concern according to level of pain intensity.

Treatment	Intensity of pain			p-value^†
	Mild (NRS 1–3): n (%)	Moderate (NRS 4–6): n (%)	Severe (NRS 7–10): n (%)
Received/used medications/drugs	36 (56.2)	76 (55.1)	88 (70.0)	0.087
Did not receive any treatment	16 (25.0)	48 (34.7)	26 (20.6)	0.10
Received/used physiotherapy/rehabilitation	10 (15.0)	12 (8.8)	11 (8.7)	0.4
Received/used surgery	0 (0.0)	0 (0.0)	2 (1.9)	0.2
Received/used home remedy or alternative medicine	8 (12.9)	9 (6.8)	7 (5.6)	0.2
Type of drug treatment received				0.3
No medication	26 (41.7)	54 (38.9)	35 (27.6)
Only NSAID	25 (40.0)	53 (38.8)	51 (40.1)
Only weak opioid	0 (0.0)	2 (1.5)	2 (2.0)
NSAID + weak opioid	0 (0.0)	3 (2.2)	2 (1.8)
Other drugs (no NSAID or opioid)	12 (18.3)	25 (18.5)	36 (28.5)

† Unless otherwise stated, χ-square test with Rao and Scott second-order correction.

n: Observations estimated by weighting real observations so that sums could differ up to ± 1 due to approximation error; %: column-weighted percentage.

NRS: Numerical rating scale; NSAID: Non-steroidal anti-inflammatory drug.