10.5826/dpc.1301a60
Introduction: Alopecia areata (AA) is a common non-scaring hair loss disease. Genetic susceptibility and environmental factors can develop the disease. 
Objectives: We investigated the association between AA and ABO and Rh blood groups.
Methods: This cross-sectional study was done on 200 patients with AA and 200 healthy controls (HCs) between March 2021 and September 2021.
Results: The prevalence of blood groups O, A, B, and AB in patients with AA was 30%, 30.5%, 10.5%, and 29%, respectively. A significant difference was detected between the two groups in the frequency of the ABO and ABO*Rh blood groups (p-value &lt; 0.05). Compared to the HCs, the prevalence of the AB and AB+ blood group was higher in AA patients. No significant relationship was detected between sex, BMI, duration of disease, age at onset, severity of alopecia tool (SALT) score, hair loss pattern, and nail involvement with ABO and Rh blood groups (p-value &gt; 0.05).
Conclusion: In conclusion, the highest difference was related to the AB+ blood group, so compared to HCs, the AB+ blood group frequency was higher in patients with AA. However, more studies with larger sample sizes on different ethnicities should be performed to verify the results of this study.
text/xml
2160-9381
2603
en
Robabeh  Abedini
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
Rh
The Relationship Between ABO And Rh Blood Groups With Alopecia Areata
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Original Article
2023-01-31
2022-05-20
2023-01-31
2023-02-27
e2023060
Dermatol Pract Concept
Introduction: Alopecia areata (AA) is a common non-scaring hair loss disease. Genetic susceptibility and environmental factors can develop the disease. 
Objectives: We investigated the association between AA and ABO and Rh blood groups.
Methods: This cross-sectional study was done on 200 patients with AA and 200 healthy controls (HCs) between March 2021 and September 2021.
Results: The prevalence of blood groups O, A, B, and AB in patients with AA was 30%, 30.5%, 10.5%, and 29%, respectively. A significant difference was detected between the two groups in the frequency of the ABO and ABO*Rh blood groups (p-value &lt; 0.05). Compared to the HCs, the prevalence of the AB and AB+ blood group was higher in AA patients. No significant relationship was detected between sex, BMI, duration of disease, age at onset, severity of alopecia tool (SALT) score, hair loss pattern, and nail involvement with ABO and Rh blood groups (p-value &gt; 0.05).
Conclusion: In conclusion, the highest difference was related to the AB+ blood group, so compared to HCs, the AB+ blood group frequency was higher in patients with AA. However, more studies with larger sample sizes on different ethnicities should be performed to verify the results of this study.
Robabeh  Abedini
2023/01/31
10.5826/dpc.1301a60
e2023060
Department of Dermatology, Razi Hospital, Tehran University of Medical Sciences (TUMS), Tehran, Iran. 
2160-9381
Rh
en
e2023060
Rather PA, Hassan I, Naaz S, Rasool F, Reshi R. Evaluation of ABO blood types in various dermatoses in Kashmiri population: A casecontrol study. Journal of Pakistan Association of Dermatologists. 01/01 2014;24:224-230.
The Relationship Between ABO And Rh Blood Groups With Alopecia Areata
https://dpcj.org/index.php/dpc/article/download/2603/1940
         The Relationship Between ABO and Rh Blood
                 Groups with Alopecia Areata
 Farzaneh Shirazi1, Safoura Shakoei2, Maryam Nasimi3, Zahra Saffarian2, Robabeh Abedini3


1 School of medicine, Tehran University of Medical Sciences (TUMS), Tehran, Iran
2 Department of Dermatology, Imam Khomeini Hospital, Tehran University of Medical Sciences (TUMS), Tehran, Iran
3 Department of Dermatology, Razi Hospital, Tehran University of Medical Sciences (TUMS), Tehran, Iran



Key words: alopecia areata, blood group, ABO, Rh
Citation: Shirazi F, Shakoei S, Nasimi M, Abedini R. The relationship between ABO and Rh blood groups with alopecia areata. Dermatol
Pract Concept. 2023;13(1):e2023060. DOI: https://doi.org/10.5826/dpc.1301a60
Accepted: April 28, 2022; Published: January 2023
Copyright: ©2023 Shirazi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-
NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use,
distribution, and reproduction in any medium, provided the original authors and source are credited.
Funding: It is financially supported by the vice-chancellor of research affairs of the Tehran University of Medical Sciences.
Competing Interests: None.
Authorship: All authors have contributed significantly to this publication
Corresponding Author: Safoura Shakoei MD, Department of Dermatology, Imam Khomeini Hospital, Tehran University of Medical
Sciences (TUMS), Tehran, Iran. Tel: 00982161192655 Fax: 00982188046767 Email: dr.shakoei@gmail.com




  ABSTRACT              Introduction: Alopecia areata (AA) is a common non-scaring hair loss disease. Genetic susceptibility
                        and environmental factors can develop the disease.
                        Objectives: We investigated the association between AA and ABO and Rh blood groups.
                        Methods: This cross-sectional study was done on 200 patients with AA and 200 healthy controls
                        (HCs) between March 2021 and September 2021.
                        Results: The prevalence of blood groups O, A, B, and AB in patients with AA was 30%, 30.5%,
                        10.5%, and 29%, respectively. A significant difference was detected between the two groups in the fre-
                        quency of the ABO and ABO*Rh blood groups (p-value < 0.05). Compared to the HCs, the prevalence
                        of the AB and AB+ blood group was higher in AA patients. No significant relationship was detected
                        between sex, BMI, duration of disease, age at onset, severity of alopecia tool (SALT) score, hair loss
                        pattern, and nail involvement with ABO and Rh blood groups (p-value > 0.05).
                        Conclusion: In conclusion, the highest difference was related to the AB+ blood group, so compared
                        to HCs, the AB+ blood group frequency was higher in patients with AA. However, more studies with
                        larger sample sizes on different ethnicities should be performed to verify the results of this study.




Original Article | Dermatol Pract Concept. 2023;13(1):e2023060                                                                         1
Introduction                                                      study and our healthy control objects were selected among
                                                                  people who did not have known systemic and skin disorders
Alopecia areata (AA) is a common non-scaring hair loss            and were often referred for cosmetic problems. We matched
disorder. The prevalence of the disease is 1 in 1000 cases        age and sex between the two groups.
and has a lifetime incidence of 2% [1]. The prevalence of            We followed the principles of the Helsinki Declaration.
the disorders indicated above is expected to be roughly 0.2       The Institutional Review Board of our university approved
percent in the overall population. Moreover, genetic suscep-      the protocol of this study. Informed consent was attained
tibility and environmental factors can also induce the disease    from all participants.
to develop [2]. However, the specific cause of the disease is
unidentified. There are several lines of evidence linking AA      Statistical Analysis
to autoimmune diseases, like type 1 diabetes mellitus (DM),       SPSS version 20 (IBM Company, USA) was applied to an-
rheumatoid arthritis (RA), systemic lupus erythematosus           alyze the variables. Continuous variables are displayed as
(SLE), vitiligo, and pemphigus Vulgaris [3-6].                    mean (standard deviation), and categorical variables are re-
    Human gene variation, such as HLA systems, is defined         ported as frequency (percentage). Student T-test (two-tailed)
by red cell isoenzymes, blood groups, hemoglobin varia-           was applied for the comparison of continuous variables. The
tions, and serum proteins [7]. The ABO blood group system         Chi-square or Fisher’s exact test was employed for the com-
includes four O, A, B, and AB common blood groups. The            parison of the categorical variables between the two study
presence of specific carbohydrate sugars on the surface of        groups. A P-value <0.05 was regarded as significant.
red blood cells distinguishes these different blood groups. A
is identified by N-acetylgalactosamine, and B is identified as
D-galactose for the B antigen. These sugars can be built on       Results
the H antigen, and in cases of the unmodified H antigen, the
                                                                  Baseline Characteristics of Participants
blood group will be O since the A and B antigens are unable
                                                                  Two hundred patients with AA and 200 HCs were included.
to adhere to the surface of red blood cells [7]. The Rhesus
                                                                  The baseline characteristics of the subjects in the AA and HC
blood group system is composed of Rhesus monkey erythro-
                                                                  groups are detailed in Table 1. The two study groups were
cyte antigens like the D antigen that can be found on the red
                                                                  comparable in terms of age, sex, and BMI.
cells of most Rh+ humans. This system is highly complicated,
                                                                     Of 200 AA patients, 81 patients had patchy hair loss, 80
and some Rh alloantigens have yet to be biochemically de-
                                                                  had Universalis hair loss, 35 had Totalis hair loss, and 3 had
scribed [8]. Because blood types are unaffected by environ-
                                                                  Ophiasis hair loss. Nail involvement was seen in 51 patients
mental factors, they are a useful and essential resource in the
                                                                  to some degree and in 19 patients as dystrophy (Table 1).
pathogenesis of diseases. In this regard, many investigations
have been conducted to study the relationship between can-
cer types, blood types, and other disorders [9].                  Comparison of Blood Groups Between AA Patients
                                                                  and HCs
                                                                  Table 2 indicates the frequency of different types of blood
Objectives                                                        groups in AA patients and HCs. ABO blood groups were
Also, some case series demonstrated substantial connections       significantly different between study groups (p=0.001). In
between blood groups and autoimmune disorders like multi-         this regard, the AA group showed a higher prevalence of
ple sclerosis, psoriasis, and pemphigus [10-12]. However, the     the AB blood group, while the prevalence of the O, A, and
exact nature of the linkage between blood groups and AA is        B blood groups was higher in HCs (p=0.001). Nonetheless,
not identified. Thus, we investigated the association between     no significant between-group differences were found based
AA and ABO, and Rh systems.                                       on O/non-O (p=0.391) and Rh (p=0.605) blood groups.
                                                                  Finally, ABO*Rh blood groups were significantly differ-
                                                                  ent between study groups (p=0.017). The most difference
Methods                                                           was related to the AB+ blood group, whose frequency was
The current cross-sectional study investigated the associa-       markedly higher in patients with AA compared to HCs
tion between AA and ABO/Rh blood groups. The study was            (Table 2).
conducted on 200 cases with AA and 200 healthy controls
(HCs) that attended our dermatology clinic in Hospitals be-       Association Between Blood Groups and Clinical
tween March 2021 and September 2021. Participants with            Characteristics in Patients with AA
other autoimmune and systemic disorders were excluded.            According to Table 3, no significant association was detected
The patients referred to the AA clinic were enrolled in the       between sex, BMI, disease duration, age of onset, SALT



2                                                                     Original Article | Dermatol Pract Concept. 2023;13(1):e2023060
                      Table 1. Baseline characteristics of the patients in AA and HC groups.
                                                                 AA group                        HC group
                                                                  (n=200)                         (n=200)      P-value
 Age [years; mean (SD)]                                         33.26 (14.33)               33.73 (12.05)       0.726a
 Sex [n (%)]                                                                                                    0.468b
   • Male                                                        77 (38.5%)                      70 (35%)
   • Female                                                     123 (61.5%)                     130 (65%)
 BMI [kg/m2; mean (SD)]                                         25.87 (17.86)               26.06 (23.11)       0.926a
 Disease duration [years; mean (SD)]                             8.56 (8.04)
 Age of onset [years; mean (SD)]                                23.15 (12.94)
 Current episode [months; mean (SD)]                             8.25 (7.71)
 SALT score [mean (SD)]                                         75.68 (29.93)
 The pattern of hair loss
   • Patchy                                                       81 (40.6)
   • Universalis                                                 80 (40%)
   • Totalis                                                     35 (17.6%)
   • Ophiasis                                                     3 (1.6%)
 Nail involvement
   • None                                                       129 (64.6%)
   • Some                                                        51 (25.6%)
   • Dystrophy                                                   19 (9.6%)

A P-value of < 0.05 was considered statistically significant.
SD: standard deviation
a
  Student T-test
b
  Chi-square test




Table 2. Comparison of different types of blood groups between AA and Healthy control group groups.
                                                  AA group                           HC group
                                                   (n=200)                            (n=200)               P-value
 ABO [n (%)]                                                                                                0.001a
   •O                                              60 (30%)                          68 (34%)
   •A                                             61 (30.5%)                         79 (39.5%)
   •B                                             21 (10.5%)                         28 (14%)
   • AB                                            58 (29%)                          25 (12.5%)
 Rh [n (%)]                                                                                                 0.605a
   • Negative                                      17 (8.5%)                         20 (10%)
   • Positive                                    183 (91.5%)                         180 (90%)
 ABO*Rh [n (%)]                                                                                             0.017b
   • O-                                            9 (4.5%)                           10 (5%)
   • A-                                            3 (1.5%)                           5 (2.5%)
   • B-                                            3 (1.5%)                           4 (3%)
   • AB-                                            2 (1%)                            1 (0.5%)
   • O+                                           51 (25.5%)                         58 (29%)
   • A+                                            58 (29%)                          74 (37%)
   • B+                                             18 (9%)                          24 (12%)
   • AB+                                           56 (28%)                          24 (12%)

HC: Healthy control. A P-value of < 0.05 was considered statistically significant.
a Chi-square test
b Fisher exact test



Original Article | Dermatol Pract Concept. 2023;13(1):e2023060                                                           3
4
                                                                                                            Table 3. Association between blood groups and clinical characteristics of patients with AA.
                                                                                                                        O             A                B               AB         P-value         Rh -            Rh +        P-value
                                                                                                                                                                                          a
                                                                  Sex [n (%)]                                                                                                     0.201                                       0.201a
                                                                    • Male                                         22 (36.7%)     30 (49.2%)      7 (33.3%)        18 (31%)                    9 (52.9%)      115 (62.8%)
                                                                    • Female                                       38 (63.3%)     31 (50.8%)      14 (66.7%)       40 (69%)                     8 (47%)        68 (37.2%)
                                                                  BMI [kg/m2; mean (SD)]                          24.37 (4.00)   24.39 (4.62)    30.16 (35..47)   28.61 (35.31)   0.687a      25.87 (17.86)   26.06 (23.11)   0.926a
                                                                  Disease duration [years; mean (SD)]              8.90 (8.68)    7.81 (7.55)     7.48 (8.02)      9.71 (7.93)    0.290a       8.83 (8.17)     6.75 (6.44)    0.310a
                                                                  Age of onset [years; mean (SD)]                23.81 (11.61)   20.67 (11.30)   19.76 (9.43)     26.31 (16.06)   0.175a      23.03 (13.11)   24.41 (11.14)   0.667a
                                                                  SALT score [mean (SD)]                         71.80 (31.40)   77.44 (29.64)   82.66 (25.92)    75.31 (30.15)   0.508a      75.51 (30.71)   77.41 (28.06)   0.804a
                                                                                                                                                                                          a
                                                                  Hair loss [n (%)]                                                                                               0.544                                       0.060a
                                                                    • Patchy                                       28 (46.7%)     20 (33.3%)      8 (38.1%)        25 (43.1%)                  7 (41.2%)       74 (40.7%)
                                                                    • Universalis                                  22 (36.7%)     29 (48.3%)      10 (47.6%)       19 (32.8%)                  9 (52.9%)       71 (39%)
                                                                    • Totalis                                        9 (15%)       9 (15%)         3 (14.3%)       14 (24.1%)                    0 (0%)        35 (19.2%)
                                                                    • Ophiasis                                      1 (1.7%)       2 (3.3%)         0 (0%)           0 (0%)                     1 (5.9%)        2 (1.1%)
                                                                                                                                                                                          a
                                                                  Nail involvement [n (%)]                                                                                        0.090                                       0.457a
                                                                    • None                                         39 (66.1%)     43 (70.5%)      16 (76.2%)       31 (53.4%)                  13 (76.5%)     116 (63.7%)
                                                                    • Some                                         15 (25.4%)     15 (24.6%)       5 (23.8%)       16 (27.6%)                  4 (23.5%)       47 (25.8%)
                                                                    • Dystrophy                                     5 (8.5%)       3 (4.9%)         0 (0%)         11 (19%)                      0 (0%)        19 (10.4%)

                                                                 P-value of < 0.05 was considered statistically significant.
                                                                 an Independent t-test




Original Article | Dermatol Pract Concept. 2023;13(1):e2023060
score, patterns of hair loss, nail involvement, and ABO/Rh          the association between alopecia areata and ABO and Rh
blood groups in patients with AA (p>0.05).                          blood groups. They indicated a similar distribution of the
                                                                    ABO blood group in the patient and healthy groups. How-

Discussion                                                          ever, the Rh+ blood group was markedly higher in the
                                                                    healthy group than the patient group. Also, Rather et al. [24]
We assessed the relationship between AA and ABO and Rh              conducted a case-control study in Kashmir to examine the
blood groups. The prevalence of blood groups O, A, B, and           relationship between ABO blood groups and different skin
AB in patients with AA was 30%, 30.5%, 10.5%, and 29%,              diseases (psoriasis, vitiligo, AA, pemphigus Vulgaris). Also,
respectively. A significant difference was detected between         37.1% of patients with psoriasis showed O blood group,
the two study groups regarding the frequency of the ABO             followed by type B (30%) and A (25.7%), with no signifi-
blood group. The highest difference was related to the AB           cant differences between study groups. In cases with vitiligo,
blood group, so compared to HCs, patients with AA showed            47.4% showed the B blood group, followed by blood groups
a higher frequency of the AB blood group. The highest dif-          O (36.8%) and A (10.5%). The frequency of A and B blood
ference was related to the AB+ blood group, so compared             groups was significantly different between vitiligo patients
to HCs, patients with AA showed a higher frequency of the           and controls. In AA patients, blood group B was detected
AB+ blood group.                                                    in 45.2% of patients, and groups O (28.6%) and A (19%)
    AA is a recurrent inflammatory disorder that affects peo-       ranked second and third, with no significant differences be-
ple of all ages and genders. Despite the disease’s importance,      tween study groups. In patients with pemphigus Vulgaris,
the specific etiology has yet to be fully understood. The ABO       40% of patients showed O and B blood groups, followed
blood group family antigens have long been identified. Blood        by blood group A (20%), with no significant differences be-
group alloantigens can be found on the membrane of epithe-          tween the groups. Contrary to the results of these studies,
lial cells and red blood cells. There is a link between blood       a significant difference was found between the two groups
types and various dermatologic conditions [9, 13, 14], lead-        in our study. The highest difference was related to the AB+
ing to the elucidation of disease pathogenesis. For instance,       blood group, so compared to the control group, patients with
malignant melanoma was found to have a statistically sig-           AA belonged to the AB blood group with higher frequency.
nificant higher risk in patients with the O blood group [9].        We also examined the relationship between the characteris-
Several previous reports have linked certain infections to spe-     tics of AA and the frequency of ABO and Rh blood groups;
cific ABO blood groups [15]. Tuberculoid leprosy is linked          no significant association was detected between ABO or Rh
to the O blood group, while lepromatous leprosy is linked to        blood groups and sex, BMI, disease duration, age of onset,
the A and B blood groups, gonorrhea to the B blood group,           SALT score, hair loss pattern, and nail involvement in pa-
smallpox to the A and B blood groups, and Escherichia coli          tients with AA.
O 157 infection to the O blood type [16]. Many studies
have investigated the association between blood groups and
autoimmune disorders like pemphigus Vulgaris, DM, RA,               Conclusion
spondyloarthropathy, vasculitis, Behcet’s disease, SLE, sys-
                                                                    A significant difference was found between the two groups
temic sclerosis, and Sjogren’s syndrome [10,17, 18]. Among
                                                                    regarding the frequency of the ABO*Rh blood group. The
these, no link was found between the ABO blood types and
                                                                    frequency of the AB+ blood group was higher in patients
pemphigus Vulgaris, which is a well-known autoimmune
                                                                    with AA. Further studies could verify the results of this study.
skin disorder [18, 19]. In the etiopathogenesis of AA, au-
toimmunity is more prominent. Different researchers have
established the relevance of T cells in the disease [20]. How-      References
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