Prevalence and quality of life in high school pupils with acne in Serbia Prevalencija i kvalitet života srednjoškolaca sa aknama u Srbiji

Background/Aim. Acne is a common problem in adolescent children with considerable emotional and psychological effects. The aim of this study was to determine the self-reported prevalence of acne and to assess its impact on the quality of life in high school pupils in Serbia. Methods. The cross-sectional study was conducted in May 2011 in two medical high schools in Serbia. Only pupils who gave a written informed consent to participate in the study (n = 440) were asked to fill in two questionnaires: short demographic questionnaire and Cardiff Acne Disability Index (CADI), a disease-specific questionnaire measuring disability induced by acne. Internal consistency (tested by Cronbach’s alpha) and item-total score correlations (Spearman's correlation analysis) were used for reliability analyses. Results. The study population consisted of 440 pupils, 281 from Belgrade and 159 from Užice. Among them 371 (84.3%) were girls and 69 (15.7%) boys, with similar sex distribution in Belgrade and Užice. The total mean age of pupils was 16.48 years (SD = 0.55). Out of 440 pupils 228 (51.8%) self-reported their acne. The acne prevalence was significantly higher in pupils from Užice (73.6%) than in those from Belgrade (39.6%). The overall mean CADI score for the whole sample was 2.87 ± 2.74, with the similar quality of life impairment in adolescents from Belgrade and from Užice. The mean Cronbach’s alpha was 0.82. Conclusion. This study shows that the quality of life impairment due to acne is mild for the majority of the affected pupils. The Serbian version of the CADI is a reliable, valid, and valuable tool for assessing the impact of acne on the quality of life.


Introduction
Acne vulgaris is one of the most common skin diseases.Almost every individual has some degree of acne during puberty, with spontaneous resolution occurring in early adult life.Occasionally, the disease persists longer or even remains a lifelong problem 1 .
Although skin diseases are sometimes thought as unimportant, even trivial, acne has a considerable psychological impact on affected individuals 2 .Previous studies on the psychosocial impact of acne have documented dissatisfaction with the appearance, embarrassment, self-consciousness and lack of self-confidence in acne patients 3,4 .Social dysfunctions have also been observed, including concerns regarding social interactions with the opposite gender, appearances in public, interactions with strangers and reduced employment opportunities 5,6 .The levels of social, psychological and emotional impairments in acne may be compared with chronic diseases such as asthma, epilepsy, diabetes and arthritis and do not necessarily follow positive correlation with dermatological damage and real cosmetic problems 7 .Because of that, it is imperative to evaluate both the psychological impact of acne on the adolescents and its repercussion on patients' quality of life.It seems that adolescents are more influenced by the psychosocial effects of acne than older patients 8 .Many teenagers with acne may suffer for years before being given effective therapy and the majority even do not seek any professional advice for managing acne 9 , although it has been proven that effective treatment results in improvement of quality of life (QoL) measurement 10 .
The aim of this study was to determine the self-reported prevalence of acne, its psychosocial impact and repercussion on quality of life in high school pupils in Serbia.

Methods
The cross-sectional study was conducted in May 2011 in two medical high schools in Serbia, one in Belgrade and another in Užice, the town in the central part of Serbia.Pupil participation was voluntary and anonymous and the written informed consent was obtained by their parents.The percentage of the second class pupils who agreed to partcipate in the study was somewhat higher in Užice (159/210; 75.7%) than in Belgrade (281/376; 74.7%).All 440 pupils (281 from Belgrade and 159 from Užice) were asked to fill in two questionnaires: short demographic questionnaire and the Cardiff Acne Disability Index -CADI 11 .
A short demographic questionnaire included questions on the presence of acne, disease duration, treatment, presence of any other coexisting skin disease and family history of acne.
The CADI is a disease-specific questionnaire measuring disability induced by acne.It is a short, 5-item questionnaire.The response to each of five questions is scored from 0 to 3, with a total maximum score of 15.The higher score means that more quality of life is impaired in affected individuals.We used the Serbian version of the CADI 12 to asses the impact of acne on the pupils' quality of life.
Written informed consent was obtained from pupils' parents.

Statistical analysis
Categorical variables were expressed as counts and percentages while continuous variables were presented as mean ± standard deviation.The differences between variables were assessed by 2 or t-test.Internal consistency (tested by Cronbach's alpha) and item-total score correlations (Spearman's correlation analysis) were used for reliability analyses.Statistical analysis was performed with the Statistical Package for the Social Sciences, SPSS version 17.0 (SPSS Inc., Chicago, IL, USA).A two-tailed probability value of 0.05 or less was considered significant.
Demographic and disease characteristics of 228 adolescents with acne are presented in Table 1.The majority of them were girls 187 (82%) and only 41 (18%) were boys with similar sex distribution in Belgrade and Užice.Pupils with acne from Užice were older compared to those from Belgrade.
Among affected pupils 22 (9.8%) also suffered from skin diseases other than acne and 101 (44.7%) had positive family history of acne.The majority of adolescents who reported acne in both cities had tried some kind of acne therapy.Acne duration was less than one year in 112 (51.4%) and more than one year in 106 (48.6%) of pupils, without significant difference between pupils from two cities.
The overall mean CADI score for the whole sample was 2.87 ± 2.74, with the similar quality of life impairment in adolescents from Belgrade and from Užice (Table 2).We found a statistically significant positive correlation between every simple question and overall mean CADI score, which was in range 0.599-0.787(Table 2).The highest correlation was found between the 4th question (patient's psychological state) and overall score.
In general, although the overall mean CADI score was low and the majority of affected pupils did not have psychological and social consequences of acne (Table 3), 8 (3.9%) of them became more aggressive, frustrated or embarrassed as a result of having acne.Also, a small, but important minority 25 (12.2%) of pupils with acne were concerned about the appearance of their skin most of the time, and 9 (4.4%) pupils felt very depressed and miserable.
The Serbian version of CADI questionnaire showed high internal consistency (the mean Cronbach's alpha was 0.82).
As presented in

Discussion
Acne vulgaris is a common, distressing dermatosis with the prevalence reaching up to 80% during adolescence 13 .Because the disease occurs in a psychologically labile period during adolescence and causes a change in appearance, acne may have negative effects on the psychological status of sufferers 14,15 , with considerable impact on their emotional health, sexual relationships and social life.
Self-reported acne occurred in 51.8% of the Serbian teenagers involved in this study.This result is in accordance with the finding of a Greek study (59.2%) 16 , but it is significantly lower than in several other studies with the range from 70.0% to over 90% 9,[17][18][19][20] .We have to mention that a significantly higher acne prevalence was in Užice (73.6%) than in Belgrade (39.6%), without any reasonable explanation for this finding.Like in several other studies 9,21 we found that acne was more frequent in boys (59.4%) than in girls (50.4%).Among the affected pupils positive family history of acne was found in 44.7%.According to Kubota et al. 22 56.8% of Japanese adolescents reported a family history of acne.The prevalence of other skin diseases was 9.2%, which is in agreement with the findings of the previous studies 18,20 .Hince our study was a self-reported study, it is possible that the pupils may have overlooked minor cutaneous problems, such as warts, or not considered them as skin problems.
Almost one half of the pupils with acne (48.6%) of both sexes reported acne duration longer than one year, with a significantly longer duration of acne among the pupils from Belgrade than those from Užice.According to the results of a Japanese study 23.4% of adolescents who reported having acne estimated acne duration of 1-2 years and 29.5% estimated duration of acne that was longer than 2 years 22 .
The consequences of having a skin disease, including acne vulgaris, may be more profound concerning the patients' quality of life.The impact of acne on the quality of life, has been recognized for over 30 years.
In this cross-sectional study the Serbian version of the CADI, a disease-specific questionnaire, was used to asses the impact of acne on the quality of life in affected adolescents.The CADI is a well-known acne disability measure and has been used in some studies to assess the burden of living with acne on a patient's experience of disability 20,[23][24][25] .
The Serbian version of the CADI questionnaire showed a high internal consistency (the mean Cronbach's alpha was 0.82).This finding indicates that Serbian version of the CADI questionnaire is reliable to measure the impact of acne on the quality of life in Serbian-speaking patients.Moreover, with only 5 questions, the CADI is also easy to administer and thus a practical tool to use in routine clinical practice.
The overall mean score of the CADI in our study for the whole sample was 2.9, which is lower in comparison with Serbian study conducted in 2010 where total CADI score was 3.6 20 , but somewhat higher than in Scottish study with the CADI score of 1.9 18 .The fact that the pupils replied together in the same classrooms with their friends being able to read their answers could prevent some of them to express how they really felt.
Although the majority of the affected pupils did not have psychological and social consequences of acne, almost 20% of pupils were moderately to severely affected by acne in terms of impairment of their quality of life that was higher than in previous similar studies conducted among the pupils 18,20 .
We found a statistically significant positive correlation between every simple question and a total CADI score.Like in the Scottish study 18 the higher scoring questions in our study pertained to the feelings about the skin appearance and patient's assessment of their current acne severity, while the lower scoring questions were related to social consequences of acne and to avoidance of sport activities, public changing facilities and clothing restrictions.Acne is associated with a greater psychological burden than a variety of disparate chronic disorders 5 and has a demonstrable association with depression, anxiety, and feelings of social isolation.It affects personality, emotions, self-image, selfesteem, and the ability to form relationships 26,27 .Gupta and Gupta 28 showed that acne is associated with higher depression scores than other dermatologic conditions.Even suicidal ideation was found to be around 6-7% in acne patients 7,28,29 .Acne in adolescents appears to have a considerable impact on emotional health 21 and affects self-image and assertiveness, factors that are important in forming friendship and personality traits 8 .
In our study a small, but important minority of the pupils with acne 3.9% became more aggressive, frustrated or embarrassed as a result of having acne, 4.4% felt very depressed and miserably, and 12.2% were concerned about the appearance of their skin most of the time.This suggests that the impact of acne can be more serious for the patients than most clinicians think it would be and thus, it is very important to focus on the subjective perception in managing acne patient, irrespective of their objective severity.
As delay in obtaining adequate treatment increases the risk of scarring, both cutaneous as well as psychological, it is important to educate teens about the availability of effective acne therapy and to encourage them to consult with dermatologist in order to stop further increase of psychological problems, reversing disability and thus to achieve a better quality of life of affected individual.
The strength of this study was the large number of adolescents surveyed from the general population (high schools), thus excluding the possibility of referral bias and overestimation of psychometric morbidity with hospitalbased data.On the other side, the QoL data from only two districts, may not be generalised to other settings in the country.The reliability of self-reported QoL data cannot be guaranteed.

Conclusion
Our study shows that acne is associated with decrease in quality of life in affected pupils.The Serbian version of the CADI questionnaire is valid and reliable to assess different aspects of quality of life among people with acne who speak Serbian language.As there are a wide variations in an individual response to having acne, quality of life scales, primarily the CADI questionnaire, may help dermatologists to understand the impact of acne on the quality of life and to take it into consideration when treating acne.

Table 4 CADI scores distribution
CADI -Cardiff Acne Disability Index.

Table 1 Characteristics of pupils with acne
* 2 test; † t-test; ns -no significant.