Association of premature androgenetic alopecia and metabolic syndrome in a young Indian population.

CONTEXT: Although evidences for association of androgenetic alopecia (AGA) with metabolic syndrome (MetS) are accruing, inconclusiveness with respect to the gender specificity and differential association of MetS with increasing severity of AGA continues to persist. Furthermore, data specific to Indian settings are relatively sparse. AIMS: The present study aimed at assessing the frequency of MetS in individuals with early AGA in Indian settings. SETTINGS AND
DESIGN: A case-control study was conducted at a trichology clinic in Bengaluru between April 2012 and September 2012 with a total of 85 cases of AGA and 85 age-matched controls.
MATERIALS AND METHODS: The Norwood-Hamilton classification was used to assess the grade of AGA. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Blood pressure, blood glucose, lipid parameters, and body mass index along with anthropometric measurements were assessed in all study participants. STATISTICAL ANALYSIS USED: Chi-square test was used to compare proportions between groups. Means were compared between groups using Student's t-test.
RESULTS: MetS was seen in a higher proportion of patients with AGA (43.5%) as compared to the control group (2.4%) and the differences were statistically significant (P < 0.001). As compared to controls, patients with AGA had higher triglycerides (P < 0.001), systolic blood pressure (P < 0.001), diastolic blood pressure (P < 0.001) along with significantly lower high-density lipoprotein cholesterol levels (P < 0.001). Severity of AGA was not associated with MetS.
CONCLUSIONS: AGA is associated with MetS in male Indian patients aged <30 years. Studies with large sample sizes may be required to conclusively define any putative associations between AGA grades and MetS.

INTRODUCTION

Numerous studies have documented the association of androgenetic alopecia (AGA) with cancers,[12] coronary artery disease,[3] diabetes,[34] hypertension,[5] and metabolic syndrome (MetS).[678]

Despite a growing body of evidences for the association between AGA and MetS, elements of inconclusiveness persist in the literature.[910] The association between AGA and MetS may be gender-specific to females.[11] Furthermore, the association of MetS with increasing severity of AGA is inconclusive.[1213]

Despite the high burden of AGA[14] and MetS,[15] India-specific data on the subject are relatively sparse.

On these premises, we investigated the association of AGA with MetS among Indian patients through a case-control study.

MATERIALS AND METHODS

A 6-month long case-control study was conducted at an out-patient trichology clinic in Bengaluru, India between April 2012 and September 2012. The study was approved by the Institutional Ethics Committee. A total of 85 male subjects (aged < 30 years) with AGA were included in the study. Subjects with scarring alopecia, alopecia areata, or other systemic disorders were excluded. The study also included 85 age-matched controls. A signed informed consent was obtained from all the participants in the study.

The Norwood-Hamilton classification was used to assess the grade of AGA.[16] MetS was defined according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) criteria.[17]

Blood pressure, blood glucose, lipid parameters, and body mass index (BMI) along with anthropometric measurements (height, weight and waist circumference) were assessed in all the study participants. Blood pressure was recorded as the mean of three consecutive readings during a period of 1 month. Fasting blood sugar (FBS) and fasting insulin were determined using glucose hexokinase reagent and chemiluminescence immunoassay, respectively. The homeostatic model assessment-estimated insulin resistance (HOMA-IR) was calculated with a cut-off value of 1.5. High-density lipoprotein cholesterol (HDL-C) (by direct enzymatic method), low-density lipoprotein (LDL) (derived), very-LDL (derived), and triglycerides (using glycerol phosphate oxidase trinder reagent) were all examined in the fasting state.

The data were analyzed using Statistical Package for the Social Sciences version 22.0 (SPSS Inc., Chicago, IL, USA). The mean ± standard deviation (SD), and the number and percentage of participants were tabulated. Means were compared across groups using t-test and proportions were compared with Karl Pearson's Chi-square test. Statistical significance was set at P < 0.05.

RESULTS

A total of 170 subjects was assigned to the study. The mean age of subjects with AGA was 26.44 ± 2.64 and that of the participants in the control group was 25.65 ± 3.19 years. Age did not differ significantly between groups (P = 0.081). Table 1 presents the mean (SD) of height, weight, and BMI along with other indices of MetS such as waist circumference, blood pressure, blood glucose, and lipid parameters observed in the case and control groups.

Table 1

Mean (SD) of demographic and laboratory parameters in AGA and control groups

Significant differences were noted between groups for all the variables except waist circumference and FBS. MetS was significantly higher in patients with AGA when compared to subjects in the control group [Table 2].

Table 2

Comparative proportions of MetS in AGA and control groups

However, there was no relationship between AGA severity and MetS [Table 3].

Table 3

Comparative proportions of MetS in various stages of AGA

Table 4 presents the comparative proportions of subjects fulfilling the NCEP-ATP III criteria for individual components of MetS in the AGA and control groups. Results of this study indicate that proportions of patients with a waist circumference > 102 cm and FBS ≥ 110 mg/dL were not significantly different between case and control groups. On the other hand, proportions of patients with blood pressure (≥130/≥85 mmHg), HDL-C (<40 mg/dL) and triglyceride levels (≥150 mg/dL) were significantly higher in the AGA group when compared to controls.

Table 4

Comparative proportions of individual components of MetS in AGA and control groups

DISCUSSION

In a recent case-control study, Acibucu et al. reported that 25% (20/60) patients with AGA had MetS as compared to 10.4% (5/48) among controls.[13] Another study by Arias-Santiago et al. indicated that criteria for MetS were met by 57.1% of the patients with AGA compared to 14.3% of the controls.[18] Results of the current study are in conformity with these findings. However, Yi et al. indicate that the association between MetS and AGA may be gender-specific; in their study, significant associations were seen only in females.[11] The current study, along with others, demonstrates a significant association in males as well. Nevertheless, gender-specific associations warrant further investigation.

Proportions of patients with higher blood pressure and triglyceride levels and lower HDL-C levels were significantly more in the AGA group when compared to controls. Ahouansou et al. posit a strong association between AGA and hypertension.[5] Furthermore, in a recent study, Agac et al. indicate a higher frequency of abnormal cardio-ankle vascular index in patients with AGA.[19] It could be possible that AGA-related increases in arterial stiffness links AGA and hypertension.

Arias-Santiago et al. reported significant higher triglyceride values in males with AGA as compared to controls.[20] Su and Chen underscores the particular importance of low HDL-C levels in the association between MetS and AGA.[8] Our findings seem to be in agreement with these lines of evidence at least to the extent that significantly lower HDL-C levels are seen in patients with AGA when compared to controls.

The current study could not identify any significant association with respect to FBS in both the groups. However, a significant association was noticed with respect to HOMA-IR (P < 0.001) in patients with AGA when compared to the control group. This is similar to the observations made in the epidemiological study by Gonzαlez-Gonzαlez et al., which reported HOMA-IR to be higher patients with AGA.[21]

The NCEP-ATP guidelines indicate that although both overweight and obesity are associated with MetS, abdominal obesity is more highly correlated with the metabolic risk factors when compared to elevated BMI.[17] In the current study, BMI along with height and weight were significantly different between groups. However, waist circumference was not significantly different between groups and was not associated with MetS.

Similar to observations of Pengsalae et al.,[6] the results of the current study could not find any relationship between AGA severity and MetS. Although this may indicate a lack of association, it is also possible that sample size within the stages of AGA is small to conclusively identify any putative associations.[13]

CONCLUSION

It appears that AGA is associated with MetS in male Indian patients aged <30 years. Studies with large sample sizes may be required to conclusively define any putative associations between AGA grades and MetS.