Association Between Acne and Body Mass Index : A Hospital Based Cross Sectional Study

Introduction: Acne vulgaris is a common and chronic inflammatory skin disease of pilosebaceous unit. Obesity is one of the biggest problems in western life style but nowadays, the problem is increasing even in low and middle-income countries. Body Mass Index (BMI) is used to accurately measure obesity. Objective: To find out the association between different categories of BMI and severity of acne. Materials and methods: This was a cross sectional prospective study conducted in the outpatient department of Gandaki Medical College from January to July, 2017. All the newly diagnosed patients with acne were included in the study. Height and weight of the patients was recorded and BMI was calculated. BMI was categorized as underweight, normal weight, overweight and obese. Type of lesions were noted and severity of acne was graded from 1 to 4. Statistical analysis was performed using SPSS version 17.0 for windows. One-way Analysis of Variance between groups (ANOVA) test was applied. P value of less than 0.05 was considered significant. Results: There were altogether 249 patients with acne. Age of the patients ranged from 10 to 44 years with mean age of 20.82 ±5.9 years. Most of the patients were in the age group of 11-20 years. Female: male ratio was 1:1.4. Majority of patients (65.5%) had normal BMI. Most of the patients had Grade 2 acne (52.6%). There was no significant association between the BMI and severity of acne (p=0.129). Conclusion: There was no significant association between BMI and severity of acne.


Introduction
A cne vulgaris is a common skin disease and is clinically characterized by the presence of comedones, papules, pustules, nodules and scars.
Obesity is an emerging problem.It is one of the biggest problems in western countries but nowadays, the problem is increasing even in low and middleincome countries.According to the report of WHO, in 2016, 39% of adults were overweight and 13% were obese. 1 Obesity is associated with peripheral hyperandrogenism; hence obesity may be associated with development of severe acne. 2 Body Mass Index (BMI) is used to accurately measure obesity. 2 There are controversial fi ndings regarding associa on between acne and BMI.
Given the increasing prevalence of acne and overweight and obesity, this study was designed to inves gate the rela onship between acne and BMI.We are not aware of any other studies of similar kind from our part.
Objec ve: To fi nd out the associa on between diff erent grades of acne and BMI.

Materials and Methods
This was a cross-sec onal prospec ve study carried out in the department of dermatology of Gandaki Medical College.Study period was from January to July 2017.Approval from the ins tu onal review board was obtained before star ng the study.Sampling method used was consecu ve sampling technique.All the newly diagnosed pa ents of acne were enrolled in the study.Follow up pa ents of acne who were already under medica on for acne were excluded from our study.Similarly, those under other systemic medicines which could infl uence acne and those who did not give consent were also excluded from the study.Informed consent was obtained from all the pa ents.Informa on on demographic data was obtained.Family history of acne in the fi rst-degree rela ves, if it was posi ve or nega ve was recorded.Height and weight were measured.BMI was calculated by dividing weight in kilograms by height in meters squared, or kg/m 2 .The World Health Organiza on Asian Pacifi c Guideline 2000 was followed for categoriza on of BMI. 3 The pa ents were classifi ed into one of the following categories: underweight (BMI < 18.5), normal weight (BMI: 18.5-23.9),overweight (BMI: 24-26.9)and obese (BMI ≥ 27).Pa ents were examined for the types of lesions like comedone, papule, pustule, cyst, abscess or scar and the severity of acne was graded using Indian classifi ca on, which classifi es acne into four grades from 1 to 4. 4 Grade 1: Comedones, occasional papules.Grade 2: Papules, comedones, few pustules.Grade 3: Predominant pustules, nodules, abscesses.Grade 4: predominantly cysts, abscesses, widespread scarring.Sta s cal analysis was performed using SPSS 17.0 for windows.One-way Analysis of Variance between groups (ANOVA) test was applied.P value was calculated and value of less than 0.05 was considered sta s cally signifi cant.

Results
A total of 249 pa ents with acne were included in the study.Age of the pa ents ranged from 10 to 44 years with mean age of 20.82 ±5.9 years.Most of the pa ents were in the age group of 11-20 years (Table 1).There was slightly a female preponderance with female: male ra o of 1:1.4.According to BMI, 65.5% were normal, 12% were overweight, 20.5 % were underweight and 2% of pa ents were obese.Majority of the pa ents had Grade 2 acne (52.6%).Only 4.8% had grade 4 acne.Acne of Grade 2 and 3 were more prevalent in females whereas grade 3 and 4 acne were more common among males (Table 2).A posi ve family history of acne was seen in 48 (19.3%) pa ents (Table 2).When comparison of BMI was made with the grades of acne, mean BMI was within the normal range for all grades of acne.Maximum number of obese pa ents had grade 4 acne, maximum number of overweight pa ents had grade 2 acne and maximum number of underweight pa ents had grade 1 acne.But there was no signifi cant associa on between the BMI categories and grades of acne (p=0.129).Similarly, there was no signifi cant associa on between the age and grades of acne (p=0.61).

Discussion
Acne vulgaris is one of the most common skin disorders aff ec ng mostly the adolescent age group that frequently con nues into adulthood. 5Most of our pa ents also belonged to the similar age group.Acne has been found more commonly in females. 2 Our study has also confi rmed the similar fi nding.
Obesity aff ects skin physiology through various mechanisms. 6Fat ssue is the source for androgen produc on. 7There is a clear role of obesity in peripheral hyperandrogenism. 8The end eff ect of hyperandrogenism is the increased sebaceous glands ac vity which is the key factor for the development of acne.
There are s ll controversial reports regarding the associa on between BMI and acne.
There have been several studies which have confi rmed the associa on between acne and BMI.Jancin B conducted a study in female teens and reported that moderate to severe acne was more prevalent among overweight and obese individuals. 9Alan S and colleague also observed a posi ve correla on between BMI and severity of acne, the groups with higher BMI had severe grades of acne. 10 Smith RN et al observed a signifi cant associa on between acne lesion counts and BMI in men aged 18 to 25 years. 11Later, this fi nding was also confi rmed by Lu LY et al, severe acne was observed in overweight and obese individuals of age 18-25 years. 12A study conducted on Italian adolescents and young adults reported that the acne risk was reduced with lower BMI, especially in males. 13 study conducted in Bri sh male soldiers revealed that individuals with acne tended to be heavier. 14In a study conducted in school children in Taiwan, acne was less prevalent in those having lower BMI (< 18.5). 2 A study by Halvorsen JA also showed that overweight and obesity were associated with acne in girls of age 18 and 19 years. 15 the other hand there are studies which have refuted the associa on between acne and its severity.
A study conducted exclusively in adult women found no diff erence in BMI when compared to severity of acne. 16A study from Taiwan has even highlighted a nega ve phenomenon, obese women presented with less acne than the non-obese cases. 17In our study, there were underweight and overweight individuals in all the grades of acne.Obese individuals were also found in all the grades of acne except in grade 3.But the associa on between BMI and severity of acne was not signifi cant.

Conclusion
Although there were propor on of pa ents who were underweight, normal, overweight or obese in almost all the grades of acne, there was no signifi cant associa on between BMI and severity of acne.However, a larger popula on-based study is indicated to validate our fi nding.
Financial disclosure: None.

Confl ict of interest to disclosure:
The principal author has not taken any part in the editorial decision.

Table 1 :
Distribu on of pa ents according to age group.

Table 2 :
Comparison of diff erent variables with grades of Acne.
BMI: Body mass index, SD: standard devia on

Table 3 :
Comparison of grades of acne with BMI.