Prevalência dos transtornos de ansiedade como causa de afastamento de trabalhadores Prevalence of anxiety disorders as a cause of workers ’ absence

Objective: to analyze the prevalence of various anxiety disorders among mental and behavioral disorders as a cause for the leave of absence of workers in the state of Piauí. Method: transversal census-based study performed with data from the National Social Security Institute. Four-hundred twelve leaves of absence of workers due to anxiety disorders in the 2015-2016 biennium were included. Results: higher prevalence was found for mixed anxiety-depressed disorder (31.2%), followed by other anxious disorders (20.6%) and generalized anxiety (14.1%). Ages from 22 to 45 years old prevailed in the group of individuals with duration of absence greater than or equal to 41 days, with statistically signifi cant difference (p < 0.001). There was no statistically signifi cant association (p = 0.004) between rural activity and increased time of absence. Conclusion: the study draws attention to the prevalence of “other anxiety disorders” as the cause of leave of absence, with emphasis on mixed anxiety-depressed disorder. Descriptors: Anxiety; Absenteeism; Social Security; Occupational Health; Mental Health. RESUMEN Objetivo: analizar la prevalencia de los diversos trastornos de ansiedad entre los trastornos mentales y comportamentales como causa del absentismo laboral de trabajadores del estado de Piauí. Método: estudio transversal y censal realizado con datos del Instituto Nacional del Seguro Social de Brasil. Se incluyeron 412 absentismos de trabajadores por trastornos de ansiedad en el bienio 2015-2016. Resultados: se verifi có mayor prevalencia para el trastorno mixto ansioso y depresivo (31,2%), seguido de otros trastornos ansiosos (20,6%) y ansiedad generalizada (14,1%). En el grupo de individuos con una duración de absentismo mayor o igual a 41 días, con una diferencia estadísticamente signifi cativa (p < 0,001), prevaleció el grupo de edad de 22 a 45 años. Se observó una asociación estadísticamente signifi cativa (p = 0,004) entre actividad rural y mayor tiempo de absentismo. Conclusión: el estudio llama la atención sobre la prevalencia de “otros trastornos ansiosos” como causa del absentismo laboral, con destaque para el trastorno mixto ansioso-depresivo. Descriptores: Ansiedad; Absentismo; Seguridad Social; Salud Laboral; Salud Mental. Prevalência dos transtornos de ansiedade como causa de afastamento de trabalhadores Prevalence of anxiety disorders as a cause of workers’ absence Prevalencia de los trastornos de ansiedad como causa de absentismo de trabajadores Márcia Astrês Fernandes E-mail: m.astres@ufpi.edu.br AUTOR CORRESPONDENTE


INTRODUCTION
Data from the World Health Organization (WHO) indicate that the prevalence of anxiety disorders (AD) in the world is 3.6%.In the American continent, this mental disorders reaches higher proportions and affects 5.6% of the population, with emphasis on Brazil where AD is present in 9.3% of the population, corresponding to the highest number of anxiety cases in the world (1) .
These statistics are reflections of the dynamics of modern society that contributes to the emergence of mental and behavioral disorders, especially anxiety, stress and depression, which have become very common diseases in doctors' offices.They can be a result of exposure to risk factors arising from the work activity and also from the relations built in the workplace (2) .
Competitiveness in the labor market coupled with the fear of unemployment induces people to subject themselves to inhumane working conditions.For example, exposure to low wages, unhealthy environments, excessive noises and heat, accumulation of functions, work shifts that exceed the amount of hours bearable and constantly changing shifts; all of these factors favor the onset of diseases in workers (3) .
Anxiety is a feeling of vague and unpleasant fear that manifests itself as discomfort or stress due to the anticipation of danger, of something unknown (4) , while ADs share traits of excessive fear and anxiety, in addition to behavioral disorders.These disorders differ in relation to the objects or situations that induce fear, anxiety or avoidance behavior and associated cognitive ideation.Thus, they differ from anxiety because they are more intense and persist beyond the appropriate periods for normal development (5) .
ADs are frequent problems when it comes to the health of workers, as they generate high costs and impact the rates of absenteeism, presenteeism and other aspects related to work, such as reductions in productivity and performance.In France, a population-based study with 4,717 workers showed that high psychological demand, too few rewards, emotional demands and insecurity are predictors of anxiety (6) .
In Brazil, mental and behavioral disorders are responsible for the overall growth in the granting of benefits, for both accident at work pay and statutory sick pay.From 2004 to 2013, the number of leaves granted due to this kind of illness increased from 615 to 12,818.In total, there was an increase in the order of 1,964% for this type of concession (7) .
Brazilian studies suggest ADs as a major cause of absences from work among mental and behavioral disorders.This is worrisome if we consider the statistics identified in recent researches, which indicate an increase in the number of absences due to anxiety disorders.In this way, new investigations should be conducted so a better understanding of AD may be obtained, unveiling the reality of the onset of this disease (8)(9) .
In this sense, nursing advances in the understanding of the work of professionals who suffer from ADs; in the prevention of diseases, providing access to quality care and managing environments; and in interventions that propose improvements to the working conditions and quality of life of workers (10) , seeing as their bio-psychic well-being is considered as a factor which heavily impacts the work activities performed (11) .

OBJECTIVE
To analyze the prevalence of various anxiety disorders among mental and behavioral disorders as cause for the leave of absence of workers in the state of Piauí.

Ethical aspects
The research was developed according to the ethical principles for research involving human beings laid out in resolution No. 466/12 of the National Health Council, being submitted and approved by the Research Ethics Committee of Universidade Federal do Piauí.

Design, study site and period
This is a cross-sectional study, developed at the headquarters of the National Social Security Institute (INSS) of the city of Teresina, Piauí, Brazil.Data were collected between June and July 2017.

Population: inclusion and exclusion criteria
Census was used as the means to obtain the study population, all the records of the workers having been obtained in the Unified Benefits System (SUB) from INSS, including sick pay and disability retirement due to anxiety disorders (AD) in the 2015-2016 biennium.A total of 1,165 absences due to mental and behavioral disorders were identified in 2015, and 1,612 in 2016.
The inclusion criteria were: absence of workers under the legal framework of the Consolidation of Labor Laws (CLT), who were over 18 years old, with AD diagnosis as cause of absence.The exclusion criteria consisted of absences with incomplete information.After application of the exclusion criteria, the sample was reduced to 412 absence records.It was not possible to identify which workers were granted sick leave more than once because of the limitations in the database, thus, the 412 records relate to the absences, which does not necessarily imply in 412 workers.

Study protocol
The data were collected through a specific instrument for this study, using variables present in the SUB: sex, date of birth, age, income, city of origin, branch of activity, time of absence, year it was granted and causes of absence according to the International Statistical Classification of Diseases and Related Health Problems (ICD-10).Chapter V of this classification published by WHO corresponds to mental and behavioral disorders and serves mainly to standardize useful diagnostic classifications for professionals working in mental health (12) .

Analysis of results and statistics
The data were entered and stored in a spreadsheet (Excel -Microsoft Office 2013) and analyzed using the Statistical Package for the Social Sciences (SPSS 20.0) and BioEstat 5.0.To describe the data collected, the absolute frequencies and percentages were calculated.
To verify the difference between the frequencies of a same variable's categories, Chi-Square Goodness of Fit test was used for the expected proportions.Chi-Square Independence test was used to verify the association between time of absence and the variables related to social security and socio-demographic characteristics.When their assumptions were violated (cells with value lower than five), G-test of independence was used.For all tests, p<0.05 was considered as significant.For bivariate analysis, the income variable was once again categorized: between one and two and more than two minimum wages.
For analysis of duration of the sick leaves, a study in which the average duration of absence of workers due to AD was 41.40 days was used as reference (13) .Thus, to verify the association between variables related to social security and sociodemographic characteristics, a time of absence lower than 41 days and corresponding to 41 days or more was adopted.

RESULTS
Most of the workers were female (56.1%), aged between 30 and 40 years old (37.4%), with income between one and two minimum wages (77.4%) and from Teresina (52.2%), carrying out industrial work activities in an urban environment (86.4%).There was no statistically significant difference in the frequency of categories in all mentioned variables (Table 1).
In relation to the profile of the absences (Table 2), 2016 accounted for the highest number of occurrences compared to 2015 (61.1% versus 39.8%) and statutory sick pay was the benefit which was most often granted (76.7%).In relation to cause, higher prevalence for mixed anxiety-depressed disorder (31.2%), followed by other anxiety disorders (20.6%), generalized anxiety (14.1%) and panic disorder (11.6%) was found.In relation to the time of absence, the majority lasted from 31 to 60 days.There was no statistically significant difference in the frequency of categories in all mentioned variables.
The bivariate analysis for time of absence (<41 or ≥41 days) with variables related to social security and socio-demographic characteristics (Table 3) demonstrated a prevalence of the age group between 22 and 45 years old in both groups; however, a higher proportion of individuals older than 45 years old was noted in the group with time of absence greater than 41 days (19.1% versus 31.8%), with statistically significant difference (p < 0.001).Although the urban sector was prevalent in both groups, it was less frequent in the group with time of absence greater than 41 days (96.8% versus 85.2%), showing statistically significant association (p = 0.004) between rural activity and greater time of absence.Sex (p = 0.762), income (p = 0.199), type of sick pay (p = 0.205) and type of disorder (p = 0.071) did not reveal statistically significant association with a time of absence greater than or equal to 41 days.

DISCUSSION
In the general population, ADs have been associated with negative results, such as functional incapacity, risk behavior, substance abuse and dependence, in addition to absences from work.This mental disorder is related to social, family, financial, interpersonal and professional factors (14) .
In relation to the association between sex and anxiety, the highest prevalence found in this study was among the female population.This can be explained by a combination of biological, psychosocial and cultural factors, including the multiple roles shared between work and family and gender inequality within and the work environment.These factors become more prominent in activities characterized by high emotional demands, low wages, lack of autonomy and lack of support and perspective in one's career (15) .
In the general population, an individual is more likely to develop ADs at 21 years of age (16) .In the workers of this research, the development of AD in the 20-year old range may have led to incapacitation for work and absence in older ages -between 30 and 40 years old.Thus, it is possible to see the impact of incapacity for work on Brazilian society, with the high socioeconomic costs that work leaves cause in the country's productive force as it affects, mainly, the active population's age group (17)(18) .
When dealing with the relationship between age and duration of absences, an investigation which examined short-term absences (less than 70 days) due to multiple causes in 2,601 employees of a French regional bank found results in line with those of this research, indicating age as a factor that contributes to the increase in the time of absence, as well as to the increase in the likelihood of presenteeism in workers.According to estimates, a 25-year old man, in comparison with a 55-year old one, has about three more days of leave of absence (19) .It is also known that ADs, if not properly treated, tend to become chronic over time, becoming more serious and demanding greater durability of the leave of absence (20) .
It is important to note that low income is associated with the most common ADs.An European research conducted with 35,634 participants found that the higher the social inequality, the greater the prevalence of AD (21) .The lack of financial resources reflects the general conditions of health and, essentially, of mental health.Thus, low income is related to the high rate of mental disorders that arise as a result of the reduction in power, insecurity and fulfillment of social roles, among other factors (22) .
The experience in urban environments is also a potential threat to mental health and well-being.A study conducted in Scotland ratifies this proposition by saying that the urban population has the highest rates of prescriptions of psychotropic medication for anxiety, depression and psychosis (23) .Also, industrial activities developed in urbanized territories have a more articulated organization in society, with a high degree of physical and mental demands (24) .
On the other hand, as can be seen in this research, workers in rural environments asked for longer leaves of absence.This finding may be resulted from the uneven distribution of health professionals between urban and rural areas.In this way, due to the lack of professionals, workers from the rural sector have insufficient health coverage for the treatment of anxiety disorders, which leads to a longer duration of absence due to incapacity for work (25) .
Thus, "other anxiety disorders", reactions to severe stress and adjustment disorders were prevalent as causes of absence among the ADs, mixed anxiety-depressed disorder having stood out, followed by "other anxiety disorders" and generalized anxiety.Other studies corroborate these results (26)(27)(28)(29) .An epidemiological research held in Vitória (ES) in a database of the Occupational Medicine Department revealed mixed anxiety-depressed disorder as prevalent (6.34%) and with the longest average duration (23.6 days) of the period of absence from work out of the causes for sick leave due to anxiety disorders (30) .
Another research conducted with institutional documents used to feed the System for Monitoring the Health of Workers in Rio Grande do Sul highlighted ADs as the second highest occurrence (18.18%) among the causes for absence.It also indicated mixed anxiety-depressed disorder, generalized anxiety and "other anxious disorders" as prevalent (31) .In an analysis conducted in São Paulo (SP) with 131 applicants for sick pay due to mental disorders, similar results were obtained regarding the prevalence of these disorders (9) .
A study on leaves of absence registered in the Integrated Healthcare Subsystem for the Federal Servers of Rondônia, in addition to ratifying the information above, added, with regard to the number of leaves, that the average days of absence due to AD was 37.4 days (ranging from 1 to 360 days) (32) .
It is estimated that about 85% of patients with depression also have significant symptoms of anxiety.Similarly, symptoms of depression occur in up to 90% of patients with anxiety.Among the causes of absence, mixed anxiety-depressed disorder is considered to be the most incapacitating and resistant to treatment, showing higher risk of suicide and being associated with social, physical  and psychological problems, in addition to jeopardizing work performance the most compared to any other isolated condition.The disorder is characterized by symptoms of anxiety and depression, which are severe enough to warrant a psychiatric diagnosis, although none of these symptoms are clearly predominant (33) .
Although it is recognized that mixed anxiety-depressed disorder has strong influence on work performance, very few studies have assessed this condition among workers (34) .
It is important to emphasize that generalized anxiety disorder, in addition to being highly prevalent and chronic, is costly, being characterized by persistent excessive worry and anxiety, in combination with various psychological and somatic complaints, such as autonomous excitement, agitation, fatigue, concentration problems, irritability and sleep issues (35) .
Emphasis should also be given to panic disorder, characterized by sudden and recurrent anxiety attacks that result in fear or concern that these attacks happen again or otherwise negatively impact life in general.DAs are considered milder and less incapacitating psychiatric disorders when compared to psychotic or mood disorders, as patients do not lose their sense of reality.However, they are associated with significant impairment in functional and social performance, like other psychiatric disorders, such as schizophrenia, major depressive disorder and dementia.Thus, panic disorder contributes independently to the reduction of health-related quality of life and to the longer duration of absences from work (36) .
Although national and international studies have investigated the topic, for the local reality, this research was innovative, original and necessary, considering the lack of investigations on the subject in Piauí.Also considering the issue of high suicide rates in the state, the importance of this work is highlighted, as it correlates them with the presence of mental disorders, including ADs.Furthermore, absences due to AD have economic and social implications which increase the need for effective measures to alleviate their consequences and reduce their onset.It should be noted that the working days lost involve a series of costs, such as expenses with hiring replacements and granting benefits, reduced productivity, increased health costs and decrease in the quality of life of workers and of the services provided.

Study limitations
The results should be interpreted considering their limitations, which comprise the study site, restricted to one region of Brazil; the reduced number of variables provided by the Unified Benefits System, in particular, the absence of information on the most affected occupational categories; and the impossibility of generalization of the results, since the research was developed with data from only one state in the country.
Contributions to the field of nursing, health or public policy The debate about leaves of absence contributes to further discussions on the subject, providing new knowledge to aid the implementation of actions focused on the mental health of workers through strategies that allow the prevention of the onset of illnesses resulted from mental and behavioral disorders, such as anxiety disorders, to promote mental health in the workplace.Thus, the study, in addition to being relevant to public health, contributes to the field of nursing, especially in the area of mental and occupational health, considering the need for research and intervention in the workplace with regard to the organization of work and its role in the promotion of mental health, as it may subsidize the adoption of preventive strategies aimed at the mental health of workers.

CONCLUSION
The year 2016 accounted for the highest number of absences due to anxiety disorders, and statutory sick pay was the type of benefit most often granted to workers.By observing the causes of the absences, prevalence of mixed anxiety-depressed disorder was noted, followed by generalized anxiety, panic disorder and "other anxiety disorders".In relation to the time of absence, the majority lasted from 31 to 60 days.
Ages from 22 to 45 years old prevailed in the group of individuals with duration of absence greater than or equal to 41 days, with statistically significant difference (p < 0.001).There was no statistically significant association (p = 0.004) between rural activity and increased time of absence.The study offers, without a doubt, contributions to the scientific community.The realization of new, more robust researches with greater geographical coverage are thus encouraged.

Table 1 -
Demographic and occupational profile of workers who were granted sick leave due to an anxiety disorder, Teresina, Piauí, Brazil, 2017Prevalence of anxiety disorders as a cause of workers' absence Fernandes MA, Ribeiro HKP, Santos JDM, Monteiro CFS, Costa RS, Soares RFS.
Note: *statistically significant p value (Chi-Square Goodness of Fit test for expected equal proportions).*Other municipalities of Piauí, where absences due to AD occurred in the studied period: Floriano, Parnaíba, Piripiri, Picos, among others.

Table 2 -
Profile of absences from work due to anxiety disorder, Teresina, Piauí, Brazil, 2017 Note: *statistically significant p value (Chi-Square Goodness of Fit test for expected equal proportions).**The category "other" includes disorders n<6: phobic anxiety disorders; agoraphobia; social phobias; other mixed anxiety disorders; non-specified anxiety disorder; obsessive-compulsive disorder with predominance of obsessive ideas or ruminations; obsessivecompulsive disorder with predominance of compulsive behaviors (obsessive rituals); obsessive-compulsive disorder, mixed form, with obsessive ideas and compulsive behaviors; nonspecified obsessive-compulsive disorder; other reactions to severe stress; dissociative movement disorders; dissociative convulsions; somatoform disorders; non-specified neurotic disorder.***Workers absent due to retirement having been excluded.

Table 3 -
Comparison of time of absence with variables related to social security, socio-demographic characteristics and type of anxiety disorder, Teresina, Piauí, Brazil, 2017

Table 3 (
concluded)Prevalence of anxiety disorders as a cause of workers' absence Fernandes MA, Ribeiro HKP, Santos JDM, Monteiro CFS, Costa RS, Soares RFS.