Clinical-epidemiological characteristics and temporal trend of new cases of grade 2 disability leprosy in the state of Maranhão, Brazil, 2011- 2020

Study contributions Main results Out of 2,147 grade 2 disability leprosy cases, the majority were male, of mixed race/skin color, multibacillary and borderline. The São Luís regional health unit showed a falling trend. Implications for services The results can guide strategies for the leprosy control program in the state, aiming at new approaches towards early diagnosis, treatment and prevention of disabilities. Perspectives Further studies are needed, such as spatial distribution of cases and detection rates of leprosy in children under 15 years of age, in order to gain a better understanding of the epidemiological profile of leprosy in Maranhão.


INTRODUCTION
Leprosy is a chronic communicable disease; and it is neglected despite representing a public health problem in Brazil and worldwide.It is an infection of the skin and peripheral nerves, with granulomatous characteristics, and which has, as an etiological agent, the Mycobacterium Leprae bacillus. 1,2Also known as Hansen's bacillus, it has an affinity for peripheral nerves and their infection can result in nerve damage with permanent physical disabilities, especially in the eyes, hands and feet, if there is no specific form of treatment. 3prosy cases can be classified according to the number of skin patches or lesions and grade of disability (GD). 4,5A person with grade 2 disability (G2D) has significant impairment, visible in the eyes, hands and feet. 3 the global level, in 2019, the rate of G2D leprosy diagnosis was 1.4 case/1 million inhabitants, reaching a total of 10,816 worldwide. 6hat was when the World Health Organization (WHO) established the goal of reducing rate of new cases with G2D to less than 1 case/1 million inhab., to be achieved by 2020. 6 Brazil, also in 2019, 2,351 new cases of G2D leprosy were reported, corresponding to an incidence rate of 11.2 cases/1 million inhabitants. 8n that year, the G2D incidence rate in the state of Maranhão was 31.5 new cases/1 million inhab., accounting for 223 cases of G2D leprosy. 7In view of data demonstrating late diagnosis of leprosy and active transmission of the disease, 4,7 the need to understand G2D leprosy diagnosis is justified in Maranhão, throughout the 2010s, especially.
The objective of this research note was to describe the clinical and epidemiological characteristics of new cases of leprosy with G20 and to analyze its trend in the state of Maranhão, Brazil, from 2011 to 2020.

METHODS
This was both a descriptive cross-sectional study, aimed at the clinical-epidemiological characterization of new G2D leprosy cases, and also an ecological study, regarding the analysis of temporal trend in detection of new G2D cases in Maranhão, between 2011 and 2020.Maranhão comprises 217 municipalities and has a population of 7,153,262 inhab. 8e ecological units analyzed were the state's regional health units (RHU).The state of Maranhão is divided into 19 RHU: Açailândia, Bacabal, Balsas, Barra do Corda, Caxias, Chapadinha, Codó, Imperatriz, Itapecuru Mirim, Pedreiras, Pinheiro, Presidente Dutra, Rosário, Santa Inês, São João dos Patos, São Luís, Timon, Viana, and Zé Doca. 9e data used for the analysis were extracted f rom the Notif iable Health Conditions

Main results
Out of 2,147 grade 2 disability leprosy cases, the majority were male, of mixed race/ skin color, multibacillary and borderline.The São Luís regional health unit showed a falling trend.

Implications for services
The results can guide strategies for the leprosy control program in the state, aiming at new approaches towards early diagnosis, treatment and prevention of disabilities.

Perspectives
Further studies are needed, such as spatial distribution of cases and detection rates of leprosy in children under 15 years of age, in order to gain a better understanding of the epidemiological profile of leprosy in Maranhão.
Information System (SINAN) on September 28, 2021, from database downloads in .cvsformat files.The compulsory leprosy notification forms provide clinical and sociodemographic data, which were used as variables in this study. 10eprosy cases with G2D at the time of diagnosis in the state of Maranhão in the period 2011-2020 were selected.A descriptive analysis of case f requency distribution (absolute and percentage) according to sociodemographic and clinicallaboratory characteristics was performed.The new G2D leprosy case detection rate was obtained by dividing the number of new cases of G2D leprosy by the population residing in the area, in the same period, multiplied by 1 million. 4he trend in new G2D case detection was classified as rising, falling or stable, according to the Prais-Winsten regression coefficient value: a positive value indicates a rising trend; a negative value means a downward trend; and a null value or p-value without significance means a stable trend. 11In order to test the statistical difference in the trend, annual percentage change (APC) was estimated, along with a 95% confidence interval (95%CI) and a 5% significance level.APC represents the average rate of change in disease incidence over a year, for each of the identified trends. 11SPSS 24.0 software was used for statistical treatment of the data.
The study project was exempted f rom submission and appraisal by a Research Ethics Committee, since it was based exclusively on public domain data.

RESULTS
We assessed 2,147 cases of individuals diagnosed with leprosy and G2D treated in the state of Maranhão, within the proposed time frame.
Regarding case description, the majority were male (71.5%) and of mixed race/skin color (66.5%), in the multibacillary operational class (95.5%) and with the borderline clinical form (58.8%).Also noteworthy were the schooling of those affected with up to 8 years of complete study (48.9%), presence of more than 5 lesions (48.4%), age above 60 years (33.2%) and negative bacilloscopy at diagnosis (32.3%), as shown in Table 1.

DISCUSSION
Detection of new G2D leprosy cases showed a stable trend for state of Maranhão as a whole, while the São Luís RHU showed a falling trend.In the state of Maranhão, this form of infection has been hyperendemic.Besides causing serious physical limitations to the individual, G2D can revive stigmas and social prejudices associated with the disease for thousands of years. 4,6,7

RESEARCH NOTE
Incidence of grade 2 disability leprosy A higher proportion of leprosy cases with G2D was identified in males.A hypothesis has been raised that the higher frequency of late diagnosis of the disease in males is due to the lower number of men seeking care in health services. 12Another hypothesis for this finding would be testosterone itself, the predominant male sex hormone, which stimulates the T helper 2 immune response, which is the main response in the multibacillary class, in which G2D is more predominant. 13prosy cases with G2D were predominant in individuals aged over 60 years.Leprosy is a chronic disease and degree of disability is related to the time course of morbidity.In the elderly individual, therefore, the chances of physical disabilities and their severity are greater. 14,15is analysis showed a higher frequency of G2D cases in individuals with low schooling.[18] There was a higher proportion of cases classif ied as multibacillary and with the borderline clinical form.The multibacillary classification, which the borderline form falls into, is identified as a risk factor for physical disabilities.This aspect of multibacillary classification and diagnosis of physical disability points to late diagnosis. 19,20garding bacilloscopy, although there were fewer positive results when compared to negative ones, the risk of cases of leprosy with positive bacilloscopy at diagnosis presenting physical disabilities related to leprosy is two times greater. 21ere was a higher proportion of G2D leprosy cases with more than 5 lesions.The presence of more than 5 lesions in a person with leprosy is a characteristic of the multibacillary operational classif ication, which is a risk factor for the development of physical disabilities due to the disease. 4,19,20ere was stability in the detection trend of new cases of leprosy with grade 2 physical disability, in almost all RHU in the state of Maranhão; the only exception was the São Luís RHU, where this trend was found to be falling.
The stationary trend in the state of Maranhão as a whole and the falling trend in São Luís can be attributed to the actions of the Family Health Strategy and its teams in the f ight against leprosy, which has been in place since 1994. 22om the year 2000 onwards, the effectiveness of the Family Health Strategy in Maranhão led to an increase in the number of diagnosed leprosy cases and, consequently, an increase in all related indicators, followed by a progressive drop in their rates. 22 limitations of this study, we highlight (i) possible underreporting of leprosy in the state of Maranhão and (ii) possible errors in filling out notification forms, given that the analysis includes only secondary data, which could compromise, mainly, the description of the clinical-epidemiological profile of the cases.
Errors in f illing out data are due to factors such as health worker lack of knowledge and overburdening, in addition to information system shortcomings. 14 conclude that this study described the clinical and epidemiological profile of new cases of leprosy with G2D in the state of Maranhão, whereby there was a predominance of males, mixed race/skin color, age over 60 years, up to 8 years of schooling, multibacillary classification and borderline clinical form, as well as negative bacilloscopy at diagnosis.A stable trend was identif ied for G2D leprosy in the state, in general, while a falling trend was only found for the São Luís RHU.We recommended reinforcing active tracing aimed at achieving early diagnosis as the best approach to leprosy, in the sense of early diagnosis, treatment and prevention of disabilities.

Table 1 -Clinical and epidemiological characteristics of new leprosy cases with G2D at diagnosis/ year, Maranhão, Brazil, 2011-2020
Rodolfo José de Oliveira Moreira et al.