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Ciência & Saúde Coletiva

Print version ISSN 1413-8123On-line version ISSN 1678-4561

Ciênc. saúde coletiva vol.24 no.11 Rio de Janeiro Nov. 2019  Epub Oct 28, 2019

http://dx.doi.org/10.1590/1413-812320182411.06352018 

ARTICLE

Chronic low back pain treatment in Brazil: inequalities and associated factors

1Departamento de Informações para a Saúde, Fiocruz. Av. Brasil 4365, Manguinhos. 21040-900. Rio de Janeiro, RJ, Brasil. dalia.fiocruz@gmail.com

2Instituto de Comunicação e Informação Científica e Tecnológica em Saúde, Fiocruz. Rio de Janeiro, RJ, Brasil.

3Instituto de Estudos Sociais e Políticos, Universidade do Estado do Rio de Janeiro. Rio de Janeiro, RJ, Brasil.


Abstract

Chronic low back pain (LBP) is one of the most common diseases in the world and one of the leading causes of years of life lost due to disability. Despite being a major public health concern, studies on access to and use of different types of treatment are scarce. The aim of this article is to describe the most common treatments for chronic LBP in Brazil, examine the factors associated with the use of these treatments, and discuss possible inequalities in the use of physical therapy/exercise and medications. A descriptive analysis was performed using data from the 2013 National Health Survey. Multiple logistic regression was conducted to determine the association between treatment use and demographic, socioeconomic, health status, access to health services, and geographical characteristics. People with higher education were 2.39 times more likely to do physiotherapy. However, no association was found between education level and medication use. People in social class A/B were almost twice as likely to do physical therapy. However, there was no association between social status and medication use. People with a very high or high degree of functional limitation were 3.5 times more likely to use medication. However, no association was observed between functional limitation and physical therapy use.

Key words Spine; Health inequalities; Physical therapy; Pharmacological treatment

Resumo

O Problema Crônico de Coluna (PCC) é uma das doenças mais prevalentes no mundo e representa uma das principais causas de anos de vida perdidos por incapacidade. Embora de grande relevância para a saúde pública, estudos sobre o acesso e a utilização dos tipos de tratamento são escassos. O objetivo deste artigo é descrever os principais tratamentos para PCC no Brasil, analisar os fatores associados à sua utilização e discutir possíveis desigualdades na utilização de fisioterapia /exercícios e a utilização de medicamentos. A partir da PNS 2013 foram realizadas análises descritivas sobre prevalência de PCC e regressão logística múltipla para analisar a associação segundo as características demográficas, socioeconômicas, a situação da saúde, a limitação causada pelo PCC, acesso a serviços de saúde e regionais. Ter ensino superior aumenta 2,39 vezes as chances de realizar fisioterapia, no entanto, a escolaridade não se mostrou associada à utilização de medicamentos. Indivíduos de estratos superiores apresentam quase 2 vezes mais chances de realizar fisioterapia, o que não foi observado para medicamentos. Sobre as condições de saúde, o aumento do grau da limitação por PCC eleva a chance de uso de medicamentos em até 3,5 vezes, mas não varia quando associado à realização de fisioterapia.

Palavras-chave Coluna vertebral; Desigualdades em saúde; Fisioterapia; Tratamento farmacológico

Introduction

Chronic low back pain (LBP) is one of the most common diseases in the world. It is also one of the leading causes of years of life lost due to disability worldwide and the most common cause in high-middle-income countries like Brasil1. Prevalence of chronic LBP in Brazilian adults in 2013 was 18.5%2-4, which is similar to rates observed in other countries5. chronic LBP is among the most common conditions for which patients seek medical care6,7, seriously affects quality of life, and is the leading cause of retirement due to disability8. In addition, the financial burden of chronic LBP is high, including high direct and indirect costs due to absenteeism, loss of productivity9, and spending on medication, physical therapy, and surgery10.

Data on the prevalence of chronic LBP in Brazil has been collected since 1998 via the complementary health surveys of the National Household Sample Survey. However, information on age at onset of chronic LBP, degree of functional limitation, and treatment type only began to be collected with the advent of the National Health Survey (NHS) in 2013, thus providing a deeper insight into this disease. Although some recent publications have addressed this theme2-4, studies of the use of treatments for chronic LBP using representative samples of the Brazilian population do not exist.

The international literature shows that the most commonly used interventions are medications and physical therapy/exercise. While the former are generally used in acute phases11, the latter are related to preventive practices12. Studies identifying the most commonly used treatments for back pain with representative samples of the Brazilian population do not exist.

The literature clearly shows the importance of interventions for the prevention and control of noncommunicable diseases, principally because it is these interventions that prevent functional impairment13. It can therefore be said that physical therapy/exercise is essential for improving the health of individuals with chronic LBP. Systematic reviews of the international literature show that rehabilitation with a focus on exercise, education, and active patient involvement is effective in reducing functional limitations caused by chronic LBP14,15. However, other studies show that medications, primarily analgesics, are the most widely used intervention11,16.

There is a lack of consensus on why medication use is generally preferred over other types of treatment. However, a population-based study conducted in Canada (n = 113,229) reported differences in access to services and types of treatment are largely explained by socioeconomic inequalities. The same study showed that the utilization of health services for chronic LBP was lower in individuals with lower education levels and socioeconomic status and that the type of treatment used varied according to sex, age and health status17.

In Brazil, the few studies that exist on types of treatment for chronic LBP are limited in terms of geographic reach and sample size. A study undertaken in Pelotas (n = 3,100) showed that the most widely-prescribed treatment for back problems was physical therapy and that the use of this treatment was greater among people with higher economic status18. Another study conducted in Belo Horizonte (n = 76) reported that 85.5% of older persons with chronic LBP did not use physical therapy and that one of the main reasons was treatment waiting lists19.

In Brazil, there are no nationwide epidemiological studies on types of treatment for chronic LBP and the factors that determine inequalities. This study therefore aimed to identify the most common treatments for chronic LBP in Brazil, examine the factors associated with the use of these treatments, and discuss possible inequalities in the use of physical therapy/exercise (as a proxy for preventive practices) and medications (as a proxy for interventions in the acute phase).

Methodology

Information source

This study used microdata from the 2013 National Health Survey (NHS), a household survey conducted by the Brazilian Institute of Geography and Statistics (IBGE). The central objective of the NHS is to characterize the health status and life styles of the population and collect information on healthcare, and health services, and access to health services20.

The NHS uses a three-stage cluster sampling design (tracts, families, and individuals). In the first stage, primary units of analysis (PUA) are selected from the master sample by simple random sampling (SRS). In the second stage, a fixed number of permanent private households are selected from each PUA selected in the first stage also using SRS. In the third stage, a household member aged 18 years and older is randomly selected from each household to respond the third (individual) section of the questionnaire.

The questionnaire is divided into three sections, the first two of which contain questions on living conditions and the socioeconomic and health status of household members. The third section, which contains questions on morbidity and life style, is individual and answered by the household member aged 18 years and older selected above21. This household member is selected from a list of eligible household members drawn up by the interviewer20. The prevalence of chronic LBP was calculated using the NHS sample (60,202 people aged 18 years and older). The dataset on treatment for chronic LBP included only individuals who self-reported the condition, resulting in a sample of 11,118 individuals.

Variables

Chronic LBP was defined based on the following dichotomous (yes/no) question: Do you have a back problem, such as lower back or neck pain, sciatica, vertebrae or disc problems?.

Type of treatment for chronic LBP was obtained from the following question: What do you do for your back problem?. Possible answers included both treatments prescribed by health professionals and self-treatment based on the following options: 1. Exercise or physical therapy; 2. use of medication or injections; 3. Acupuncture; and 4. Other (please specify). The interviewee was allowed to select more than one answer. For the purposes of comparison, the answers were grouped as follows: not carrying out any treatment; only medication; only physical therapy/exercise; medication and physical therapy/exercise; and only acupuncture or others.

The demographic variables used for the analysis were: sex (male, female) and age (18 to 49 years, 50 to 59 years, and 60 years and over). The socioeconomic variables were: education level (no education, partially completed primary education, completed primary education, completed secondary education, higher education); skin color/race (white, brown, black, yellow, or indigenous); and social class, based on the Brazilian Association of Market Research Companies classification (D/E, B, A/B)22. The health status variables were: self-reported health (very poor or poor, moderate, good, very good); degree of functional limitation due to chronic LBP (very high or high, moderate, low, no limitation), depression (depression, no depression); and number of chronic comorbidities (one, two, or three or more). The variables related to access to health services were: household covered by the Family Health Strategy (FHS) (yes, no) and private health insurance (yes, no). The geographical variables were: region (North, Northeast, Southeast, South, and Center-West) and place of residence (urban, rural).

Statistical analysis

The data was analyzed using descriptive statistics: prevalence of chronic LBP and percentage distribution of type of treatment by demographic, socioeconomic, and geographical characteristics, health status, access to health services, and degree of functional limitation.

Logistic regression was performed to determine the strength of association between the dependent variables (use of some kind of treatment, physical therapy/exercise use, and medication use) and independent variables using odds ratios (OR) and 95% confidence interval (CI95%). Associations were tested between each of these three outcomes and the following independent variables: sex, age, education level, race/skin color, social class, self-reported health, depression, comorbidity, degree of functional limitation due to chronic LBP, FHS coverage, health insurance, place of residence, and region. Crude odds ratios (bivariate) were calculated for the three outcomes and adjusted odds ratios (multivariate) for the two final outcomes for each independent variable.

Since a multi-stage cluster sampling design was used, all analyses were performed using the complex samples options of the statistical software package Statistical Package for the Social Sciences (IBM SPSS 22).

Results

The prevalence of chronic LBP in Brazil is 18.5% (CI95% 17.8-19.1) (n = 11,118). This rate varies according to demographic, socioeconomic, health status, access to health services, and geographic characteristics. Prevalence of chronic LBP is higher in women than in men (21.1 CI95% 20.2-21.9 and 15.5 CI 95% 14.8-16.4, respectively). Prevalence was also shown to increase gradually with age, reaching up to 28.1% (CI95% 26.6-29.7) in older persons. Prevalence of chronic LBP was higher among people with low socioeconomic status and poor health status (Table 1).

Table 1 Characteristics of the population aged 18 years and over and prevalence and distribution of chronic LBP by demographic, socioeconomic, health status, access to health services, and geographical characteristics. Brazil, 2013. 

Sample Chronic LBP
% n Chronic LBP Prevalence CI 95% IC 95%
Total sample 60202 100.0 11118 18.5 17.8 - 19.1
Total Brazilian population 146308458 100.0 27021122 18.5 -
Demographic variables
Sex
Male 28357 47.1 4408 15.5 14.8 - 16.4
Female 31845 52.9 6711 21.1 20.2 - 21.9
Age
18-49 39594 65.8 5517 13.9 13.3 - 14.6
50-59 9742 16.2 2548 26.2 24.6 - 27.8
60 and over 10866 18.0 3053 28.1 26.6 - 29.7
Socioeconomic variables
Education level
Without education 8240 13.7 2109 25.6 23.9 - 27.4
Primary incomplete 15198 25.2 3651 24.0 22.8 - 25.3
Primary complete 9347 15.5 1476 15.8 14.5 - 17.2
Secondary complete 16878 28.0 2405 14.2 13.3 - 15.2
Higher education 10539 17.5 1478 14.0 12.8 - 15.3
Race/skin color
Non-white 31629 52.5 5613 17.7 17.0 - 18.6
White 28573 47.5 5505 19.3 18.4 - 20.2
Social class
D/E 14085 23.4 3106 22.1 20.7 - 23.4
C 25738 42.8 4787 18.6 17.8 - 19.5
A/B 20379 33.9 3226 15.8 14.8 - 16.9
Health status
Self-reported health
Poor or very poor 3506 5.8 1540 43.9 41.1 - 46.8
Moderate 16887 28.0 4790 28.4 27.1 - 29.7
Good 31801 52.8 4114 12.9 12.3 - 13.7
Very good 8008 13.3 674 8.4 7.4 - 9.6
Depression
No 46292 76.9 9310 16.7 16.1 - 17.4
Yes 13910 23.1 1808 39.3 36.9 - 41.8
Comorbidities
None 39045 64.9 5024 12.9 12.2 - 13.5
1 disease 14082 23.4 3464 24.6 23.3 - 25.9
2 diseases 5052 8.4 1685 33.4 30.9 - 35.9
3 or more diseases 2023 3.4 946 46.8 42.9 - 50.6
Access to health services
Household covered by the FHS
Yes 32875 54.6 6477 19.7 18.8 - 20.6
No 20826 34.6 3515 16.9 15.9 - 17.9
Don't know 6502 10.8 1126 17.3 15.9 - 18.9
Health insurance
Yes 18217 30.3 3316 18.2 17.1 - 19.4
No 41985 69.7 7803 18.6 17.9 - 19.3
Geographical variables
Region
North 4479 7.4 755 16.9 15.3 - 18.6
Northeast 16026 26.6 3071 19.2 18.1 - 20.3
Southeast 26365 43.8 4469 16.9 15.9 - 18.0
South 8898 14.8 2076 23.3 21.6 -25.2
Center-West 4434 7.4 748 16.9 15.7 - 18.1
Place of residence
Rural 8302 13.8 1771 21.3 19.6 - 23.1
Urban 51900 86.2 9348 18.0 17.3 - 18.7

Source: 2013 National Health Survey (NHS).

Table 2 shows treatment use among individuals with chronic LBP, revealing that almost half of the sample (46.4%) did not use any kind of treatment. This proportion was slightly higher among men than women (50.6% compared to 43.6%, respectively) and women were 1.3 times more likely than men to use some kind of treatment.

Table 2 Types of treatment for chronic LBP and likelihood (odds ratio) of use of some kind of treatment by demographic, socioeconomic, health status, access to health services, and geographical characteristics. Brazil, 2013. 

Types of treatment Likelihood of using some kind of treatment
Not carrying out any treatment Only medication Only physical therapy/exercise Medication and physical therapy/exercise Only acupuncture or others Crude OR CI
Total 46.4 31.6 10.4 8.4 3.2 - -
Demographic variables
Sex
Male 50.6 30.6 9.2 5.9 3.7 1 -
Female 43.6 32.2 11.2 10.1 2.9 1.32 1.16 - 1.51
Age
18-49 49.4 30.2 9.8 7.4 3.2 1 - -
50-59 42.9 33.0 10.7 10.3 3.2 1.30 1.10 - 1.53
60 and over 43.9 32.8 11.3 8.7 3.4 1.25 1.08 - 1.45
Socioeconomic variables
Education level
Without education 47.2 40.0 4.5 6.5 1.8 1 -
Primary incomplete 44.8 35.7 7.9 8.1 3.5 1.11 0.93 - 1.31
Primary complete 49.4 29.2 9.5 9.3 2.6 0.92 0.73 - 1.15
Secondary complete 49.8 26.1 12.1 8.8 3.1 0.90 0.74 - 1.10
Higher education 40.5 20.5 23.1 10.6 5.3 1.31 1.05 - 1.64
Race/skin color
Non-white 48.0 33.5 8.3 7.5 2.7 1 -
White 44.7 29.5 12.6 9.4 3.8 0.87 0.76 - 1.00
Social class
D/E 48.4 38.5 4.5 5.7 2.8 1 - -
C 47.3 32.6 9.3 8.2 2.7 1.05 0.90 - 1.22
A/B 43.1 23.3 17.8 11.4 4.4 1.24 1.05 - 1.47
Health status
Self-reported health
Poor or very poor 39.3 43.4 5.4 9.7 2.1 1 -
Moderate 43.2 35.5 8.7 9.3 3.3 0.85 0.70 - 1.03
Good 51.7 24.6 12.6 7.7 3.4 0.61 0.50 - 0.73
Very good 52.2 19.0 20.4 4.0 4.5 0.60 0.44 - 0.81
Depression
No 47.8 30.9 10.5 7.6 3.1 1 -
Yes 39.0 34.8 9.9 12.7 3.6 1.44 1.21 - 1.71
Comorbidities
None 50.4 29.3 9.7 7.3 3.3 1 -
1 disease 46.8 31.3 10.9 8.0 3.0 1.15 0.99 - 1.35
2 diseases 39.5 34.8 12.0 10.4 3.2 1.56 1.30 - 1.86
3 or more diseases 35.7 38.9 9.6 12.5 3.3 1.83 1.42 - 2.37
Degree of functional limitation due to chronic LBP
No limitation 57.6 20.7 13.0 4.5 4.3 1 -
Low degree 45.5 31.5 11.4 8.5 3.1 1.63 1.37 - 1.93
Moderate degree 40.8 36.9 8.4 11.4 2.6 1.97 1.62 - 2.39
High of very high degree 32.1 47.4 5.6 12.9 2.0 2.87 2.32 - 3.55
Access to health services
Household covered by the FHS
Yes 45.8 34.1 8.6 9.0 2.5 1 -
No 46.9 27.6 13.2 8.1 4.2 0.96 0.83 - 1.10
Don't know 48.1 29.3 12.3 6.2 4.1 0.91 0.74 - 1.13
Health insurance
Yes 43.8 23.4 17.9 10.5 4.5 1 -
No 47.5 35.0 7.2 7.6 2.7 1.16 1.00 - 1.35
Geographical variables
Region
North 45.9 34.2 9.1 6.2 4.5 1 -
Northeast 49.0 35.8 6.7 5.9 2.5 0.88 0.72 - 1.08
Southeast 48.0 27.7 12.0 8.8 3.5 0.92 0.75 - 1.13
South 41.6 31.5 12.5 11.0 3.4 1.19 0.95 - 1.49
Center-West 39.7 34.5 11.5 11.6 2.6 1.29 1.01 - 1.64
Place of residence
Rural 48.0 39.0 5.0 4.9 3.2 1 -
Urban 46.1 30.1 11.4 9.1 3.2 1.08 0.94 - 1.25

Source: 2013 National Health Survey (NHS).

People with higher socioeconomic status and poorer health status were more likely to use some kind of treatment. Having a higher education level and being in social class A or B increased the likelihood of using some kind of treatment by 31% (OR 1.31 CI95% 1.05 - 1.64) and 24% (OR 1.24 CI95% 1.05 - 1.47), respectively. Poor self-reported health, depression, having various comorbidities, and having a very high or high degree of functional limitation also increased the likelihood of using some kind of treatment.

Overall, the most common treatment was medication use (40%), with or without the use of other interventions. The overall prevalence of medication use without physical therapy/exercise was 31.6%, with little variation according to sex and age. The prevalence of medication use without physical therapy/exercise was higher in the following groups: people without any education (40%), people with social class D/E (38.5%), non-whites (33.5%), people with poor or very poor self-reported health (43.4%), people with depression (34.8%), people with more than three comorbidities (38.9%), people with a very high or high degree of functional limitation (47.4%), people without health insurance (35%), people in households covered by the FHS (34.1%), people living in rural areas (39%), and people living in the north, northeast, and center-west regions (34.2%, 35.8%, and 34.5, respectively).

The second most common treatment was physical therapy/exercise (18.8%). The prevalence of physical therapy/exercise without medication use was 10.4%. The prevalence of only physical therapy/exercise was higher among people with a higher education level (ranging from 4.5% in people without education to 23.1% in those with higher education), people in social class A/B (17.8%), whites (12.6%), people with good self-reported health (20.4%), and people with health insurance (17.9%).

The overall prevalence of medication and physical therapy/exercise was 8.4%. This rate was higher in women than in men (10.1% compared to 5.9%, respectively), people with higher education (10.6%), and those in social class A/B (11.4%), and slightly higher in whites (9.4%) in comparison to non-whites (7.5%).

The prevalence of medication and physical therapy/exercise was also higher in people with poorer health status (9.7% in people with poor or very poor self-reported health, 12.7% in people with depression, 12.5% in people with three or more comorbidities, and 12.9% in people with a high or very high degree of functional limitation). With regard to access to health services, the prevalence of the medication and physical therapy/exercise was 9% in people living in households covered by the FHS and 10.5% in people with health insurance. Prevalence also varied according to region, being lower in the north and northeast regions.

The least common treatment was only acupuncture and others (3.2%), with only slight differences according demographic characteristics. This type of treatment was more common among people with higher education (5.3%), people in social class A/B (4.4%), and whites (3.8%). Prevalence was also higher in people with very good self-reported health (4.5%), people without functional limitations (4.3%), people with insurance (4.5% compared to 2.7% in people without insurance), and households covered by the FHS (4.2% compared to 2.5% in people from households that were not registered), showing that health status and access to healthcare services had a positive impact on the use of this treatment. The northeast and center-west regions showed the lowest prevalence rates for this type of treatment (2.5% and 2.6%, respectively).

The results from the logistic regression presented in Table 2 show that women were more likely to use some kind of treatment than men (OR 1.32 CI95% 1.16-1.51). People in the 50 to 59 years and 60 years and over age groups were more likely to use some kind of treatment than those in the 18 to 49 year group (30%; OR 1.30 IC 1.10-1.53 and 25%; OR 1.25 CI95%1.08 -1.45, respectively). The use of some kind of treatment increased with increasing socioeconomic status, with people with higher education being 1.31 times more likely than those without education (OR 1.31 CI95% 1.05 - 1.64) and people in social class A/B 1.24 times more likely than those in class D/E (OR 1.24 CI95% 1.05 - 1.47).

Poor health status increased the likelihood of using some kind of treatment. The variable that showed the strongest correlation was degree of functional limitation, where people with a high or very high level of limitation were almost 3 times more likely to use some kind of treatment (OR 2.87 CI95% 2.32 - 3.55). No correlation was found between access to health services and region and the likelihood of using some kind of treatment.

Table 3 shows the crude and adjusted odds ratios for the two most common types of treatment (medication use and physical therapy/exercise use). In the crude model, women were 1.27 times more likely to use medications (OR 1.27 CI95%1.11 - 1.45) and 1.95 times more likely to use physical therapy/exercise than men (OR 1.95 CI95%1.66 - 2.30). The same relationship, albeit weaker, was maintained in the adjusted model, where women were 1.2 times more likely to use medication (OR 1.20 CI95%1.04 - 1.38) and 1.37 times more likely to physical therapy/exercise (OR 1.37 CI95%1.13 - 1.66).

Table 3 Likelihood (odds ratio) of medication use and physical therapy use for chronic LBP by demographic, socioeconomic, health status, access to health services, and geographical characteristics. Brazil, 2013. 

Medication use Physical therapy use
Crude OR CI 95% Adjusted OR CI 95% Crude OR CI 95% Adjusted OR CI 95%
Demographic variables
Sex
Male 1 - 1.00 1 - 1.00
Female 1.27 1.11 - 1.45 1.20 1.04 - 1.38 1.95 1.66 - 2.30 1.37 1.13 - 1.66
Age
18 - 49 1 - 1.00 1 - 1.00 -
50 - 59 1.27 1.07 - 1.49 1.01 0.84 - 1.21 2.36 1.91 - 2.91 1.38 1.09 - 1.74
60 and over 1.18 1.00 - 1.38 0.89 0.73 - 1.08 2.42 2.05 - 2.86 1.42 1.13 - 1.80
Socioeconomic variables
Education level
Without education 1 - 1.00 1 - 1.00 -
Primary incomplete 0.90 0.76 - 1.07 0.91 0.75 - 1.10 1.38 1.05 - 1.82 1.26 0.95 - 1.68
Primary complete 0.72 0.57 - 0.91 0.81 0.62 - 1.04 1.05 0.78 - 1.43 1.47 1.05 - 2.07
Secondary complete 0.62 0.51 - 0.75 0.76 0.59 - 0.98 1.06 0.80 - 1.41 1.49 1.05 - 2.11
Higher education 0.52 0.41 - 0.66 0.74 0.55 - 1.01 1.71 1.29 - 2.27 2.39 1.63 - 3.49
Race/skin color
Non-white 1 - 1.00 1 - 1.00 -
White 1.09 0.96 - 1.24 1.04 0.89 - 1.21 1.54 1.31 - 1.81 0.98 0.80 - 1.20
Social class
D/E 1 - 1.00 1 - 1.00 -
C 0.87 0.75 - 1.01 1.13 0.94 - 1.34 1.45 1.19 - 1.78 1.43 1.14 - 1.79
A/B 0.67 0.57 - 0.80 1.22 0.94 - 1.57 2.10 1.70 - 2.58 1.96 1.43 - 2.69
Health status
Self-reported health
Poor or very poor 1 - 1.00 1 - 1.00 -
Moderate 0.72 0.60 - 0.86 0.98 0.80 - 1.20 0.76 0.58 - 0.99 1.11 0.81 - 1.51
Good 0.42 0.35 - 0.51 0.74 0.58 - 0.93 0.38 0.29 - 0.50 1.08 0.78 - 1.51
Very good 0.26 0.19 - 0.37 0.55 0.38 - 0.80 0.29 0.20 - 0.44 1.25 0.78 - 2.02
Depression
No 1 - 1.00 1 - 1.00 -
Yes 1.44 1.22 - 1.71 1.11 0.90 - 1.38 3.11 2.58 - 3.76 0.98 0.76 - 1.27
Comorbidities
None 1 - 1.00 1 - 1.00 -
1 disease 1.12 0.95 - 1.33 0.99 0.82 - 1.20 2.19 1.82 - 2.63 0.99 0.80 - 1.23
2 diseases 1.43 1.19 - 1.72 1.10 0.88 - 1.38 3.62 2.95 - 4.45 1.20 0.92 - 1.56
3 or more diseases 1.83 1.44 - 2.34 1.18 0.86 - 1.62 5.16 3.84 - 6.95 1.04 0.70 - 1.54
Degree of functional limitation due to chronic LBP
No limitation 1 - 1.00 1 - 1.00 -
Low degree 1.98 1.67 - 2.35 1.78 1.49 - 2.12 1.18 0.95 - 1.47 1.44 1.14 - 1.81
Moderate degree 2.77 2.28 - 3.37 2.35 1.91 - 2.89 1.17 0.90 - 1.52 1.47 1.12 - 1.93
High of very high degree 4.52 3.63 - 5.63 3.53 2.78 - 4.48 1.08 0.84 - 1.37 1.48 1.14 - 1.93
Access to health services
Household covered by the FHS
Yes 1 - 1.00 1 - 1.00 -
No 0.73 0.64 - 0.85 0.88 0.75 - 1.02 1.05 0.88 - 1.24 0.86 0.70 - 1.06
Don't know 0.73 0.59 - 0.90 0.78 0.62 - 0.97 0.92 0.69 - 1.22 0.95 0.68 - 1.32
Health insurance
No 1 - 1.00 1 - 1.00 -
Yes 0.69 0.59 - 0.80 0.85 0.71 - 1.03 1.93 1.63 - 2.27 1.44 1.15 - 1.80
Geographical variables
Region
North 1 - 1.00 1 - 1.00 -
Northeast 1.06 0.86 - 1.30 0.95 0.76 - 1.17 0.93 0.72 - 1.20 0.80 0.62 - 1.03
Southeast 0.85 0.68 - 1.05 0.86 0.68 - 1.08 1.38 1.07 - 1.78 0.99 0.76 - 1.30
South 1.09 0.87 - 1.36 0.98 0.76 - 1.27 2.18 1.64 - 2.89 1.27 0.93 - 1.74
Center-West 1.26 0.99 - 1.61 1.16 0.90 - 1.50 1.52 1.18 - 1.97 1.20 0.92 - 1.56
Place of residence
Rural 1 - 1.00 1 - 1.00 -
Urban 0.83 0.72 - 0.96 1.02 0.87 - 1.20 1.80 1.44 - 2.24 1.46 1.13 - 1.87

Source: 2013 National Health Survey (NHS).

The likelihood of doing physical therapy/exercise increased with age. In the crude model, people in the 60 years and over age group were 2.42 times more likely to do physical therapy/exercise (2.42 CI95% 2.05 - 2.86) than the 18 to 49 years group. This association was maintained in the adjusted model, where the 60 years and over age group was 1.42 times more likely to do physical therapy/exercise (OR 1.42 CI95% 1.13 - 1.80) than the 18 to 49 years group. There was no significant association between age and use of medication (Table 4).

Table 4 Likelihood (odds ratio) of doing physical therapy/exercise as a treatment for chronic LBP by demographic, socioeconomic, health status, access to health services, and geographical characteristics. Brazil, 2013. 

Crude OR Model 1 Model 2 Model 3 Model 4
OR CI 95% OR CI 95% OR CI 95% OR CI 95% OR CI 95%
Demographic variables
Sex
Male 1 - 1.00 1.00 - 1.00 1.00
Female 1.95 1.66 - 2.30 1.93 1.63 - 2.28 1.38 1.14 - 1.67 1.38 1.14 - 1.66 1.37 1.13 - 1.66
Age
18 - 49 1 - 1.00 1.00 - 1.00 - 1.00 -
50 - 59 2.36 1.91 - 2.91 2.37 1.92 - 2.93 1.42 1.12 - 1.79 1.38 1.09 - 1.75 1.38 1.09 - 1.74
60 and over 2.42 2.05 - 2.86 2.60 2.16 - 3.12 1.50 1.20 - 1.89 1.43 1.13 - 1.81 1.42 1.13 - 1.80
Socioeconomic variables
Education level
Without education 1 - 1.00 - 1.00 - 1.00 - 1.00 -
Primary incomplete 1.38 1.05 - 1.82 1.34 1.02 - 1.77 1.34 1.01 - 1.77 1.31 0.99 - 1.74 1.26 0.95 - 1.68
Primary complete 1.05 0.78 - 1.43 1.18 0.85 - 1.63 1.60 1.14 - 2.25 1.55 1.10 - 2.17 1.47 1.05 - 2.07
Secondary complete 1.06 0.80 - 1.41 1.03 0.74 - 1.43 1.58 1.12 - 2.22 1.50 1.06 - 2.12 1.49 1.05 - 2.11
Higher education 1.71 1.29 - 2.27 1.35 0.95 - 1.92 2.63 1.81 - 3.81 2.38 1.63 - 3.47 2.39 1.63 - 3.49
Race/skin color
Non-white 1 - 1.00 - - 1.00 - 1.00 -
White 1.54 1.31 - 1.81 1.20 1.01 - 1.43 1.08 0.90 - 1.30 1.06 0.88 - 1.28 0.98 0.80 - 1.20
Social class
D/E 1 - 1.00 - 1.00 - 1.00 - 1.00 -
C 1.45 1.19 - 1.78 1.59 1.29 - 1.97 1.64 1.32 - 2.05 1.58 1.26 - 1.98 1.43 1.14 - 1.79
A/B 2.10 1.70 - 2.58 2.26 1.70 - 2.99 2.48 1.83 - 3.37 2.24 1.63 - 3.07 1.96 1.43 - 2.69
Health status
Self-reported health
Poor or very poor 1 - - 1.00 - 1.00 - 1.00 -
Moderate 0.76 0.58 - 0.99 1.17 0.84 - 1.63 1.13 0.83 - 1.53 1.11 0.81 - 1.51
Good 0.38 0.29 - 0.50 1.39 0.87 - 2.22 1.13 0.81 - 1.57 1.08 0.78 - 1.51
Very good 0.29 0.20 - 0.44 1.14 0.84 - 1.55 1.33 0.83 - 2.15 1.25 0.78 - 2.02
Depression
No 1 - - 1.00 - 1.00 - 1.00 -
Yes 3.11 2.58 - 3.76 0.99 0.77 - 1.28 1.01 0.78 - 1.30 0.98 0.76 - 1.27
Comorbidities
None 1 - - 1.00 - 1.00 - 1.00 -
1 disease 2.19 1.82 - 2.63 1.03 0.83 - 1.28 1.02 0.82 - 1.26 0.99 0.80 - 1.23
2 diseases 3.62 2.95 - 4.45 1.26 0.97 - 1.65 1.24 0.95 - 1.61 1.20 0.92 - 1.56
3 or more diseases 5.16 3.84 - 6.95 1.16 0.78 - 1.71 1.11 0.75 - 1.65 1.04 0.70 - 1.54
Degree of functional limitation due to chronic LBP
No limitation 1 - - 1.00 - 1.00 - 1.00 -
Low degree 1.18 0.95 - 1.47 1.42 1.13 - 1.79 1.44 1.15 - 1.82 1.44 1.14 - 1.81
Moderate degree 1.17 0.90 - 1.52 1.45 1.11 - 1.90 1.46 1.11 - 1.92 1.47 1.12 - 1.93
High of very high degree 1.08 0.84 - 1.37 1.47 1.13 - 1.92 1.50 1.15 - 1.95 1.48 1.14 - 1.93
Access to health services
Household covered by the FHS
Yes 1 - - - - 1.00 - 1.00 -
No 1.05 0.88 - 1.24 - 0.87 0.71 - 1.06 0.86 0.70 - 1.06
Don't know 0.92 0.69 - 1.22 - 0.94 0.68 - 1.31 0.95 0.68 - 1.32
Health insurance
No 1 - - - - 1.00 - 1.00 -
Yes 1.93 1.63 - 2.27 - 1.48 1.18 - 1.85 1.44 1.15 - 1.80
Geographical variables
Region
North 1 - - - - - 1.00 -
Northeast 0.93 0.72 - 1.20 - 0.80 0.62 - 1.03
Southeast 1.38 1.07 - 1.78 - 0.99 0.76 - 1.30
South 2.18 1.64 - 2.89 - 1.27 0.93 - 1.74
Center-West 1.52 1.18 - 1.97 - 1.20 0.92 - 1.56
Place of residence
Rural 1 - - - - - 1.00 -
Urban 1.80 1.44 - 2.24 - 1.46 1.13 - 1.87

Source: 2013 National Health Survey (NHS).

Model 1: Adjusted for demographic and socioeconomic variables. Model 2: Adjusted for demographic, socioeconomic, and health status variables. Model 3: Adjusted for demographic, socioeconomic, health status, and access to health services variables. Model 4: Adjusted for demographic, socioeconomic, health status, access to health services, and geographical variables.

Socioeconomic inequality has a greater effect on physical therapy/exercise use than on medication use. In the crude model, people with higher education were 1.7 times more likely to do physical therapy/exercise (CI95% 1.29 - 2.27). This effect was even more pronounced in the adjusted model, were people in this group are 2.39 times more likely to do physical therapy/exercise (OR 2.39 CI95% 1.63 - 3.49). There was no significant association between education level and medication use.

With regard to social class, in the adjusted model people in social class A/B were 1.96 times more likely to do physical therapy (OR 1.96 CI95% 1.43 - 2.69) than classes D/E. This association was not found for use of medication. Skin color was associated with physical therapy/exercise in the crude model (OR 1.54 CI95% 1.31 - 1.81); however, this association lost its significance in the adjusted model.

With respect to health status, no association was found between self-reported health, having depression, having comorbidities, and degree of functional limitation and physical therapy/exercise. However, the findings show that having better self-reported health reduced the likelihood of medication use. People with very good self-reported health were 1.55 times less likely to use medications than those with poor self-reported health (OR 0.55 CI95% 0.38-0.80) in the adjusted model. Degree of functional limitation showed a strong positive association with medication use in both models. People with a high or very high degree of functional limitation were 3.5 times more likely to use medications in the adjusted model. Having depression and comorbidities was associated with medication use in the crude model; however, this association lost its significance in the adjusted model.

With regard to access to health services, living in a household covered by the FHS was associated with medication use in the crude model; however, this association lost its significance in the adjusted model. There was no significant association between this characteristic and physical therapy/exercise. Having health insurance was associated with physical therapy/exercise in both models (OR 1.44 CI95% 1.15 - 1.80).

No association was found between medication and physical therapy/exercise and region. However, people living in urban areas were more likely to do physical therapy/exercise than those in rural areas in the crude model (OR 1.80 CI95% 1.44 - 2.24). This association was maintained in the adjusted model (OR 1.46 CI95% 1.13 - 1.87).

Discussion

The findings show that the most commonly used treatments for chronic LBP in Brazil are physical therapy/exercise and use of medication. Almost half of people with chronic LBP (46.4%) do not use any kind of treatment, which is a large proportion compared with other countries. In this respect, a study conducted in North Carolina reported that 20% individuals with back problems did not seek treatment23.

Although there is still no “gold standard” for chronic LBP management15, the use of continuous treatment is widely indicated by the literature to reduce the negative impact of this condition on quality of life, avoid surgery, and lower healthcare costs24. Research in various countries has shown that rehabilitation focusing on exercise, education, and active patient involvement is effective in reducing functional limitations caused by chronic LBP14,15.

Despite these recommendations, our results show that a relatively small proportion of individuals with chronic LBP seek continuous treatment such as physical therapy/exercise, corroborating the findings of a systematic review of the international literature25. On the other hand, the data also shows that medication use - which is generally associated with acute phases of chronic LBP - is the most commonly used treatment, which is consistent with the literature11,26. The preference for medication over continuous treatments such as physical therapy may be explained by the high cost of the latter and the time it takes to notice the benefits27.

The findings also show that the likelihood of medication use increases significantly with increasing levels of functional limitation due to chronic LBP, with individuals with a high or very high level of limitation being 3.5 times more likely to use medication than those without limitation. Despite the high level of medication use, the NHS does not provide information on the types of medications used or whether they were prescribed by a doctor. A study conducted in the United States covering the period 1999 to 2010 showed that the most commonly used medications were narcotics, benzodiazepines, and muscle relaxants24, while a systematic review of chronic LBP in Africa showed that the most widely used medications were analgesics16.

While Krismer and Van Tulder11 points out that there is evidence to support the use of simple analgesics, nonsteroidal anti-inflammatory drugs, and muscle relaxants to relieve back pain, a study conducted by Martell et al.28 covering the period 1966 and 2005 reported that the indiscriminate use of opioids commonly prescribed for the short-term relief of chronic LBP is a serious public health problem. This finding supports the above theory explaining low adherence to medium and long-term treatments.

Our findings also show that individuals with functional limitations are more likely to use physical therapy, as shown by a study conducted in Canada17. However, the degree of functional limitation does not influence the likelihood of using this type of intervention. Despite being considered more expensive, physical therapy can reduce time spent in hospitals and therefore treatment costs29.

In the present study, people with higher education and in social class A/B were more likely to use physical therapy. These findings are similar to those of a population-based study conducted by Freburger North Carolina30 showing that education level and income were enabling characteristics associated with physical therapy use. A population-based study conducted in Pelotas/RS (n = 3,100)29 also showed that higher social class was associated with physical therapy use, yet failed to demonstrate a significant association with education level. The association between high education level and physical therapy use found by this study may have been influenced by higher education levels among individuals in higher social classes.

Type of treatment is associated with socioeconomic status, which includes social class and income. The present study showed that race was not a statistically significant predictor of dependent variables. Other studies have also shown that care-seeking for chronic LBP is similar between races31. Furthermore, in accordance with the literature, the findings of the present study show that individuals with health insurance were more likely to see a physical therapist30. Physical therapy use is also influenced by the relationship between having health insurance and income/social class.

Despite the fact that studies have shown improvements in access to health services in Brazil32,33, this study revealed that the use of some kind of treatment was lower among vulnerable population groups with low social class. With respect to sex, our study shows that women are more likely to seek treatment than men. These findings are similar to those reported by Carey in a study using a representative sample of households in North Carolina23. The same study showed that care seeking was greater among individuals with high pain scores and poor functional status, as observed by the present study.

In Brazil, representative data on access to health services, medical appointments, and treatment for chronic LBP is scarce. Since the frequency of hospital admission for this condition is low, health information systems do not provide adequate information for epidemiological studies. The advantage of household health surveys is that they are representative and also consider individuals who do not seek health services. It is vital that studies addressing treatment of chronic LBP use a combination of both formal and informal data sources, since informal interventions such as physical activity can often be more effective than traditional practices like physical therapy and chiropraxy34. Furthermore, common practices such as self-medication cannot be observed in hospital records.

The NHS is the first nationally representative health survey in Brazil to include questions on types of treatment for chronic LBP, disease duration, and age at onset of functional limitations. The questions on treatment encompass both therapies indicated by health professionals and self-treatment (exercise or physical therapy, medications or injections, acupuncture and others). However, the survey has certain limitations, such as the categorization of types of intervention. In this respect, the NHS does not separate physical therapy and exercise, the latter of which is widely recommended in the literature for the prevention of chronic LBP.

With respect to the use of medication/injections, the NHS does not provide information on the type of medications used or whether they were prescribed by a doctor, preventing the study of self-medication. Another limitation is that the survey only captures information on people undergoing treatment for chronic LBP at the time of the interview, ignoring previous treatment and its duration, meaning that it is not possible to analyze treatment continuity and make comparisons with occasional interventions, which is central to the discussion of chronic LBP treatment.

Studies show that consultation with a doctor or other health professional is common among people with chronic LBP23,35,36. A systematic review of the prevalence of low back pain in Africa showed that doctors were the most commonly consulted health professionals for this condition16, while other international studies have shown that chiropraxy is a common treatment35,37. However, this type of treatment was not considered separately by the NHS, preventing comparisons with other studies.

Conclusion

The findings show that the use of continuous treatments such as physical therapy for chronic LBP is strongly associated with socioeconomic status. No association was found between socioeconomic status and medication use. However, lower health status is associated with increased use of medications.

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Received: November 07, 2017; Accepted: April 13, 2018; Published: April 15, 2018

Collaborations

DE Romero and J Muzy participated in study conception and design, data analysis and interpretation, and in the drafting of this manuscript. L Maia and AP Marques participated in data analysis and interpretation and in the drafting of this manuscript. PRB Borges participated in data analysis and interpretation. D Castanheira participated in data interpretation and the drafting of this manuscript.

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