The correlation between ABO blood types and acne vulgaris severity

Acne vulgaris is a chronic inflammatory disease with multifactorial etiology. Studies on the pathogenesis of acne are still important. Recently, various studies have been conducted on the significance of genetics in the pathogenesis of acne. Blood group is transferred genetically and could affect the development, progress, and severity of certain diseases.

Studies on acne pathogenesis are still important. Recently, various studies have been conducted on the significance of genetics in acne pathogenesis. 2 It was reported that acne in adolescence has a genetic predisposition, and acne is more common in individuals with a family history of acne. 3 Furthermore, evidence from recent studies on extended families and twins revealed the significance of heredity in acne pathogenesis. 4 The ABO blood categorization was first discovered in the early 20th century to improve the safety of blood transfusions. Each of the two alleles that encode the ABO blood groups contains antigen A, antigen B, or neither. The combination of these alleles determines an individual's blood phenotype, which could be O, A, B, or AB. 5 Blood group is transferred genetically and could affect the development, progress, and severity of certain diseases. 6 The role of the ABO antigenic system in disease pathogenesis was associated with TNFα and several pro-inflammatory molecules. Elevated TNFα was associated with inflammation. [7][8][9] It is known that inflammation is an etiopathogenesis factor in acne vulgaris and plays a role in acne development. 1 Possible correlations were investigated in diseases such as rosacea, lichen planus, skin cancer, vitiligo, pemphigus, and psoriasis in dermatology. 10 Also recently, the correlation between acne vulgaris and blood group was investigated but contradictory findings were reported. [11][12][13] In this study aimed to investigated the correlation between acne vulgaris severity and ABO blood groups. The healthy control group included 1000 18-65 years old healthy individuals who applied to the hospital to obtain health reports for job application or routine check-ups. Gags (global acne-grading system) values which are routinely used in our clinic, were used to evaluate acne severity ( 14 ). Acne severity was determined based on the blood group and Rh factor values available in our hospital automation system patient files in the both groups.

| Statistical analysis
SPSS for Windows software, v.24.0 software was employed to analyze the study data. Patient gender and blood group distributions were analyzed with frequency and percentage analysis in the study.
Furthermore, the mean and standard deviations were calculated to determine the participant mean age, and "One-Way ANOVA" and post hoc LSD tests were employed to determine the differences between the patient and control group mean age. Chi-square test was used to determine whether the differences between patient and control group gender and blood group distributions were statistically significant. The level of significance was determined as 99% (p < 0.01) and 95% (p < 0.05).

| RE SULTS
It was observed that significant difference was found between the two groups with regard to gender (X 2 :154.908; p:0.000). 79.5% of the 263 patients with mild acne, 74.4% of the 117 patients with severe acne, and 40.5% of the 1000 controls were female. A significant difference was determined between patients with mild acne and the control group, and between patients with severe acne and the control group favoring the female individuals. No significant difference was observed between patients with mild acne and severe acne based on gender ( Table 1).
The analysis revealed a statistically significant difference between the mean age of the patients with mild and severe acne and the control group (t:37.127; p:0.0001). The differences were significant between the mean age of the patients with mild acne and the control group, between the mean age of patients with severe acne and the control group, and between the mean age of patients with mild acne and that of the patients with severe acne. Thus, the age of the patients with mild (24.43 ± 5.60) and severe acne (21.96 ± 3.85) was lower when compared to the age of the controls (27.22 ± 7.97). Severe acne patients had the lowest mean age, while the mean ages of mild and severe acne patients were lower than controls ( Table 2).
The analysis of the ABO blood types of the acne patients demonstrated that 38.8% of the patients with mild acne were type-A, 16% were type-B, 12.9% were type-AB, and 32.3% were type-0 blood.
It was determined that 51.3% of the patients with severe acne were type-A, 9.04% were type-B, 10.3% were type-AB, and 29.0% were type-0. In the control group, it was observed that 40.4% were type-A, 19.3% were type-B, 7.5% were type-AB, and 32.8% were type-0.
Significant difference was found between ABO blood types of the acne patients and the control group (X 2 :17.756; p:0.007). The differences were significant between mild acne patients and the control group, and severe acne patients and the control group. No significant difference was found between the blood types of the mild and severe acne patients. Thus, when compared to the control group, the incidence of severe acne in individuals with type-A blood was higher when compared to mild acne patients, while the incidence of mild acne in other blood groups was higher when compared to the control group and severe acne patients (Figure 1).
No significant difference was found between mild and severe acne patients, and the control group based on Rh blood type (X 2 :0.812; p:0.666) ( Table 3).

| DISCUSS ION
Blood types, hemoglobin variants, erythrocyte cell isoenzymes, and serum proteins are genetic markers employed to identify human gene variations such as HLA systems. There are four common blood types in the ABO system: O, A, B, and AB. 15,16 Rhesus system is the second most prevalent blood classification system following the ABO. It is defined with two methods based on the presence of Rh factor or immunogenic D antigen in the erythrocyte surface. When D antigen is present, it is defined as Rh positive, when it is not present, it is defined as Rh negative. 10,16 ABO antigens are usually expressed by several tissues, including erythrocytes, gastrointestinal mucosa, endothelium, heart, kidney, and various tissues. In the skin, blood type antigens can be expressed in many different regions. These regions include the stratum corneum, stratum granulosum, acrosyringium, and hair follicle regions. 17

TA B L E 2
Age average of the patient and control groups.
on the contrary this correlation has not been clarified in certain diseases. 18 It was reported that changes in the release of ABO antigens in the epithelium were associated with wound healing, oral mucosal cancers, and cellular maturation. 19 Following a study where a correlation was reported between stomach cancer and blood type-A, other studies demonstrated a correlation between the blood type and several diseases. 18 Certain studies that investigated the correlation between dermatological diseases and blood types reported associations with certain blood types, while others failed to determine a correlation. Certain studies suggested that psoriasis was more common among individuals with 0 blood type, while others could not evidence a correlation between psoriasis and blood type. 20 In a study where Macsween et al. investigated patients with various skin disorders such as acne, rosacea, alopecia, and warts based on the ABO blood type, they reported that seborrheic diathesis was more common in individuals with B blood type, and lichen planus was more common in individuals with A blood type. 21 Moshaverinia et al. 22 did not report a correlation between blood type antigens and oral lichen planus. Kumar et al. 23  protective against the disease. 24 Tuberculoid leprosy was associated with type-0, lepromatous leprosy was associated with types A and B, gonorrhea was associated with type-B, and smallpox was associated with types A and AB. 6 The risk of malignant melanoma slightly increased in patients with the blood group 0 Rh. 25 The correlation between blood type and vitiligo has been controversial since certain studies reported that the frequency of AB blood type was higher in vitiligo patients when compared to other blood types, while others reported that there was no correlation between vitiligo and ABO blood type. 26,27 Another study reported that there was no significant correlation between blood type and keloid. 28 No correlation was reported between chronic spontaneous urticaria and ABO blood type. 29 The blood type distribution of alopecia areata patients and healthy donors was similar. 30 Öztürk et al. 10 reported that there was no significant correlation between blood type and rosacea in another study.
In the study conducted by Terzi et al. 11 on acne vulgaris patients, the ratio of patients with A and B blood types was higher when compared to the control group; however, the difference was not statistically significant. The rate of patients with AB blood type was significantly higher when compared to the control group, and the rate of patients with O blood type was significantly lower when compared to the control group. No significant difference was found between the two groups based on Rh factor distribution.
In a cross-sectional study that investigated the correlation between severe acne vulgaris and blood type, it was determined that the mean patient age was 24.11 ± 6.8, and no relationship was found between age, gender, disease severity, and ABO/Rh blood type. 12 F I G U R E 1 Distribution of ABO blood group in acne vulgaris and control groups.

Mild acne patient
Severe acne patient

| CON CLUS ION
In our study, the rate of female patients was significantly higher in the patient group. The mean patient age was significantly lower when compared to the controls. The mean age of severe acne patients was significantly lower than those with mild acne. When compared to the control group, the incidence of severe acne was higher in individuals with type-A blood when compared to patients with mild acne, while the incidence of mild acne was higher in other blood types when compared to the control group and severe acne. It is known that ABO blood type isoantigens are expressed in the keratogenic regions of the skin layers and hair follicles. The expression of A blood type antigens, which was reported to be significantly higher in the present study, especially in severe acne patients, could contribute to the etiopathogenesis of acne vulgaris and alleviate acne severity via follicular hyperkeratinization. Further studies that would be conducted with larger samples in different centers could confirm the current study findings.

FU N D I N G I N FO R M ATI O N
No specific funding was procured in the present study.

CO N FLI C T O F I NTE R E S T S TATE M E NT
The authors declare no conflict of interest.

E TH I C A L A PPROVA L
This study was approved by the Ethics Committee from Firat University (2022/05-26).

DATA AVA I L A B I L I T Y S TAT E M E N T
The data that support the findings of this study are available from the corresponding author upon reasonable request.