Pain magnitude at the preferential “gateway” of the Single Health System

BACKGROUND AND OBJECTIVES: Since the dawn of civilization, pain was and still is a major concern for humankind. It is estimated that 80% of the world population look for the health system due to pain complaints. American epidemiological studies show that 20% of adults assisted by primary health attention services suffer from chronic pain. This study aimed at identifying the incidence of pain in adults in the Primary Health Attention. METHODS: Documental research carried out in a family health unit of the city of Tupanatinga/PE. Sample was made up of medical charts of users (adults) registered in the Unit. A total of 1071 charts they analyzed. A verbal scale was used to evaluate the incidence of pain. RESULTS: According to the verbal scale, the prevalence of pain among users of the family health unit was 42%. Associating pain to gender, it was observed that there has been statistically significant association (p<0.001), where the presence of pain in women (69.1%) was more frequent as compared to males (30.9%). CONCLUSION: The results of this study show us the “scenario” of pain at the preferential “Gateway” of the Single Health System. The high incidence of pain in Primary Attention warns for the magnitude of the problem, making imperative to treat pain as a severe public health problem with social relevance.


INTRODUCTION
Pain is still a major concern for humankind.Since the dawn of humanity, as suggested by some pre-history drawings and several written documents from the past, men have always tried to explain reasons that would justify pain and the procedures for its control 1 .Pain may be defined as a subjective experience which may be associated to real or potential tissue injury, which may be described both in terms of such injuries and by both characteristics.Regardless of the acceptance and amplitude of this definition, pain is considered an experience, a truly subjective and personal sensation.It has sensory, affective, autonomic and behavioral aspects 2 .Its complexity and multidimensional nature, which are evident even in most elementary analyses of different types of pain, have virtually prevented the development of an adequate definition of pain, or what is probably the most important, have impaired the development of a general pain theory, as well as the derivation of clearly effective management techniques 2 .Pain is a symptom and one of the most frequent reasons for looking for medical assistance.It is estimated that 80% of the world population look for health systems due to this morbidity 3 .American epidemiologic studies show that 20% of adults seeking the Primary Health Attention (APS) have chronic pain 4 .The Brazilian Society for the Study of Pain (SBED) has started in 2012 an evaluation of available Brazilian epidemiologic studies on pain and has found that they are still scarce.Sixteen have called the attention -some of them more often mentioned by the international scientific literature on pain epidemiology.Only one of them was carried out in a Basic Health Unit (UBS), where the prevalence of pain was 30% 5 .In APS, pain is frequently referred by patients and that is why diagnosis and management at the first level of health assistance is important, thus preventing it to reach more complex health attention levels 3 .Pain control is a mandatory public health practice, especially in basic health attention.It is important to highlight that the lack of adequate diagnosis and management in the acute phase may favor pain chronicity and worsening of its clinical presentation 3 .In Brazil, there is no consensus about which would be the expected solvability of APS services, but studies about this level of assistance characterize APS solvability in 80%, since it functions as the primary gateway for regular use services 6 .It is noticed that the limits of Basic Attention (BA) data and indicators may be evidenced by the under-notification of pain as the fifth vital sign.So the question is: to what extent is the basic health attention offered to the Brazilian population integral, since this could be a potential scenario for new interventions 7 .In light of this perspective, knowing the incidence of pain in primary attention would be highly relevant since the literature brings important insights about other health assistance levels and few studies on APS.For such, identifying pain behavior in the primary "Gateway" of the Single Health System (SUS) would contribute to guide the decision making process and the evolution of care, as well as to decrease its chronicity and costs generated for health systems with adequate diagnosis and management in the acute phase.This study aimed at identifying the incidence of pain in adults in the APS.

METHODS
This was a documental research having as research field the Family Health Unit (USF) of Povoado Cabo do Campo, city of Tupanatinga.This city is located 304 km to the West of the city of Recife, in the mesoregion of Agreste Pernambucano and micro-region of Vale do Ipanema.It has a population of 24,703 inhabitants according to data of the Brazilian Institute of Geography and Statistics (IBGE) 8 .Sample was made up of medical charts of users registered in the USF.We decided to select 50% of medical charts of adult users (20 to 59 years old) registered in the Health Unit, which represented a total of 1,071 analyzed medical charts.The verbal scale (VS) was used to evaluate the incidence of pain, which was implemented since 2013 in the routine as the fifth vital sign.Descriptive statistics were presented by means of absolute and relative percentage frequency distribution for categorical variables.The prevalence of pain was calculated and confidence interval was estimated as 95%.Pearson Chi-Square test was used to analyze the association of pain and gender.Statistical significance was 5%.Software used for analysis was STATA version 12.0.Before starting the study, formal authorization of the Basic Attention Coordination of the city was obtained to carry out the study in the Health Unit.This study was approved by the Research Ethics Committee, Faculdade da Associação Caruaruense de Ensino Superior of Caruaru, Pernambuco, opinion CEP-900.126 in December 05, 2014.It has to be highlighted that we have obtained the Authorization Term for the non utilization of the Free and Informed Consent Term (FICT) because this was a study with secondary data (medical charts and others), respecting regulating guidelines of Resolution 466/2012 of the National Health Council/Department of Health, aiming at assuring rights and duties regarding the scientific community, studied subjects and the State.

RESULTS
After obtaining information with the selected tool and treating data, most relevant statements to understand the questions which have guided this study were selected.Information was collected from medical records of 1,071 USF users, of whom 55.6% (n=596) were females and 44.4% (n=475) were males.Most prevalent age group was from 50 to 59 years with 37%.With regard to education, 34.8% were illiterate.Most users (62.1%) had a job, while 30.1% were retired and 7.8% had other activities.Associating pain and gender, it was observed that there has been statistically significant association (p<0.001)where pain among females (69.1%) was more frequent as compared to males (30.9%) (Table 1).According to the visual analog scale (VAS), frequency of pain among USF users was 42% (CI 95%: 39 to 45%) (Table 2).

DISCUSSION
Our results have shown high incidence of pain in adults (42%) in the primary "gateway" of SUS, which is APS.This incidence confirms most studies with different subgroups of socio-economic, demographic and health variables.In addi-tion, it shows high predominance of females as compared to males with regard to pain complaints (69.1%).A cross-sectional study focusing on users of the Family Health Strategy of the city of Santa Maria -Rio Grande do Sul, has shown that females were predominant (87%) in pain complaints 3 .A different study on the presence of pain complaints in patients classified according to the Manchester protocol has shown that 57.4% were females and 42.6% were males 9 .A study on the profile of chronic pain patients treated in a pain ambulatory of a major city to the South of Brazil, has shown that most patients were females (67.6%) and that the age group from 40 to 49 years represented 32.4% of pain complaints.
In 2012, a cross-sectional study with individuals of both genders and above 18 years of age, who were in a waiting room of a basic health unit and who were evaluated with the pain visual analog scale, has shown that 37.8% of respondents had chronic pain at evaluation time 3 .The first population-based study in South America, and the third worldwide, to use the four questions of the Douleur Neuropathique 4 (DN4) tool in epidemiologic studies was carried out with 1,597 people in São Luis, Brazil.DN4 was originally developed and validated in France and is a questionnaire to be applied by the clinician with 10 items related to pain characteristics.It has shown excellent properties to track/identify pain worldwide.According to this study, in São Luis the prevalence of chronic pain was 42% and the percentage of pain with neuropathic characteristics was approximately 10% 11 .So, the percentages of one of the most important epidemiologic studies carried out in Brazil confirm data of our research.What differs our study from the abovementioned ones are data collection tools used to measure pain.Although our results call the attention to the magnitude of the problem, little is still known about the social burden of pain in the preferential SUS gateway.It is indispensable to treat pain as a serious public health problem in all levels of health assistance.This study also assures us that pain measurement is extremely important in APS, because it is impossible to handle such common problem in the preferential SUS gateway without a measure where to base treatment or therapeutic management.One should add that recent studies have concluded that there is a gap with regard to human resources qualification to manage pain.It is known that effective pain control is health professionals' duty, in addition to being a right of those suffering it and a fundamental step for the effective humanization of health services 12 .Our study also shows that pain among females points to a clinic further directed to physiological, perceptive, behavioral and hormonal aspects of the gender.It was also observed that the diversity of tools to evaluate pain limits the comparison among studies.Further analyses are recommended during the implementation of pain evaluation tools.

CONCLUSION
Understanding the incidence of pain in APS is paramount because Primary Attention is the lever for the transformation of the system as a whole and the attention to pain recording is directly reflected on decreasing chronicity and costs generated to health systems by adequate diagnosis and management in the acute phase.

Table 1 .
Distribution of pain by gender, among users assisted by the Family Health Unit of Povoado de Cabo do Campo, Tupanatinga, Pernambuco

Table 2 .
Incidence of pain, according to the verbal scale attached to medical charts of users of the Family Health Unit of Povoado de Cabo do Campo, Tupanatinga, Pernambuco