Risk factors and severity of melasma in patients attending dermatology outpatient department of a tertiary care hospital: A cross-sectional study

Abstract

Melasma is a chronic acquired dysfunction of melanogenesis characterized by dark brown irregular macules on skin. Genetic predisposition, pregnancy, sun exposure, and hormonal therapy are common risk factors. Prevalence of melasma is variable, ranging from 5% to 46%. This study aimed to assess the severity and potential risk factors of melasma in a tertiary care setting. An analytical cross-sectional study was conducted on patients with melasma visiting dermatology department of a tertiary care center in Nepal. Nonprobability consecutive sampling was adopted. Severity of melasma was assessed using the Modified Melasma Area and Severity Index score. Data analysis was performed using the Statistical Package for the Social Sciences, version-23. Bivariate analysis was done by using Student t test/Mann–Whitney U test, or Chi-square/Fischer exact test for continuous and categorical variables, respectively. The overall median Modified Melasma Area and Severity Index score was 5.40 (3.60–6.75). Most patients (168, 88.42%) had mild melasma. The severity score was significantly higher in older age (P = .024), women having parity more than 3 (P = .014), centrofacial pattern (P = .024), and patients having dermatological comorbidities (P = .014). Severity was significantly lower in those who used cosmetics at home. Moreover, the use of digital screens was not associated with an increase in melasma severity. Most of the cases had mild melasma. Severity was significantly associated with age, parity, pattern, practice of cosmetic use, and presence of dermatological comorbidities.

1. Introduction

Melasma is a chronic acquired dysfunction of human melanogenesis resulting in hypermelanosis of light to dark brown color.^[1–4] It develops as symmetrical, diffuse, irregular macules in sun-exposed areas, mostly on the face and neck, slowly over the course of time. Melasma affects people of all age, gender, and race but is more common in people with Fitzpatrick skin type 4 to 6 and fertile women.^[4,5] The exact pathogenesis of melasma is still unknown, but several factors have been implicated in its development. The most common risk factors are genetic predisposition, pregnancy, sun exposure, and hormonal therapies like oral contraceptive pills and cosmetics use.^[4,6]

Melasma is usually seen in women after adolescence, during pregnancy, or during the use of oral contraceptive pills showing association between melasma and female hormones.^[7] According to a global survey 48% have a family history of melasma which shows the genetic predisposition of the disease.^[8] Other factors that have been implicated are photosensitizing medications, endocrinopathies, emotional stress, anticonvulsants, nutritional deficiencies, and ovarian and thyroid dysfunction. The prevalence of melasma has been found to be highly variable, ranging from 5% to 46%, depending on the population.^[9]

Studies on melasma severity have rarely been conducted in our setting. The main objective of this study was to describe the different sociodemographic characteristics and potential risk factors of patients with melasma, and to assess the severity of melasma using a reliable scoring tool in a tertiary care center. Information on severity and risk factors is crucial for developing targeted prevention and management strategies, which would help to minimize the incidence and impact of this pigmentation disorder among the general public.

2. Methods

2.1. Study setting

The study was conducted in the Dermatology Outpatient Department (OPD) of a tertiary care center located in Kathmandu, Nepal.

2.2. Study design and participants

This is an analytical cross-sectional study conducted on patients, aged 18 to 65 years, visiting the Dermatology OPD of Shree Birendra Hospital, Kathmandu, Nepal. All patients with melasma as a dermatological condition were included in our study.

2.3. Sampling and sample size

A nonprobability convenient sampling method was used. Patients were taken consecutively according to their visit to the OPD. The minimum sample size was calculated using Cochran formula as 95.43; taking a prevalence of 46% (from our reference study^[9]), a confidence interval of 95%, and a standard error of 10%. Since it was a convenience sampling, we doubled the sample size to increase the validity of our study. Thus, we used a sample size of 190.

2.4. Data collection and study variables

Semistructured questionnaires were prepared, and data were collected through direct interviews with patients. Data were collected from July 2021 to the end of November 2021. The questionnaire contained questions on sociodemographic characteristics, risk factors, and melasma severity. The data included sociodemographic factors such as age, sex, occupation, religion, and education. Risk factors included family history, pregnancy, parity, Fitzpatrick skin type, age at onset, hormonal therapy, sun exposure, sun protection, and cosmetic usage. The severity of melasma was assessed using the Modified Melasma Area and Severity Score.^[10] Data on presence of dermatological (bacterial/fungal infections, vesicobullous disorders, dermatitis, xerosis and acne), and nondermatological comorbidities (hypertension, diabetes mellitus, chronic obstructive pulmonary disease, thyroid disorders, and chronic gastritis) were also collected. Usage of digital screen included use of mobile, television, computer, and tablet, was taken to correlate with severity of score.

2.5. Ethical consideration

Ethical approval was obtained from the Institutional Review Committee (Reg. No. 427, Ref No. 245), Nepalese Army Institute of Health Sciences. Permission was obtained from the hospital authority and head of the department before starting the study. Informed verbal consent was obtained from all patients, as approved by Institutional Review Committee, due to minimal risk involved and practical feasibility in the high-patient-flow outpatient setting. Patient identities were kept anonymous.

2.6. Data analysis

Data were entered and analyzed using the Statistical Package for the Social Sciences, version-23. Shapiro–Wilk W test was performed to check the normality of continuous data. For normally distributed variables, mean/standard deviation was calculated, and for data with nonnormally distributed variables, median/interquartile range was calculated. The level of significance was set at P < .05 with a 95% confidence interval, considering 10% margin of error throughout the analysis. The Modified Melasma Area and Severity Index (mMASI) score was our dependent variable (continuous variable) and all other sociodemographic and potential risk factors were independent variables (categorical variables). The Mann–Whitney U test/Kruskal–Wallis H test was used to check an association between these variables.

3. Results

A total of 190 cases were taken and analyzed. Out of these, 36 (18.9%) and 154 (81.05%) were males and females, respectively. The median age was 38.00 (32.00–50.00) years. Majority of them (125, 65.79%) belonged to the 31 to 55 years age category. Sociodemographic characteristics are presented in Table 1.

Table 1.

Sociodemographic and other potential risk factors for melasma along with mMASI score.

SN	Variables		mMASI score	P value
1	Age categories: (in years)	≤30 (n = 41, 21.58%) 31–55 (n = 125, 65.79%) >55 (n = 24, 12.63%)	4.60 (3.00–6.80) 5.40 (3.60–6.60) 6.60 (4.39–8.28)	.024
2	Gender	Male (n = 36, 18.9%) Female (n = 154, 81.05%)	5.40 (4.14–6.68) 5.40 (3.60–6.76)	.509
3	Ethnicity	Brahmin (n = 77, 40.53%) Chhetri (n = 60, 31.58%) Newar (n = 37, 19.47%) Kirant (n = 12, 6.32%) Madhesi (n = 4, 2.11%)	5.40 (3.60–7.20) 5.40 (3.60–7.50) 5.35 (3.38–6.60) 5.05 (3.95–7.20) 5.33 (3.04–6.53)	.911
4	Religion	Hinduism (n = 163, 85.79%) Buddhism (n = 18, 9.47%) Christianity (n = 9, 4.74%)	5.35 (3.60–6.75) 5.50 (3.83–7.28) 5.00 (3.75–6.90)	.740
5	Family history of melasma	Yes (n = 118, 62.11%) No (n = 72, 37.89%)	5.28 (3.60–7.20) 5.40 (3.60–6.60)	.840
6	Past pregnancy	Yes (n = 128, 67.37%) No (n = 72, 37.89%)	5.28 (3.60–7.20) 5.40 (3.60–6.60)	.840
7	Parity (if pregnant in the past)	≤3 (n = 110, 85.94%) >3 (n = 18, 14.06)	5.40 (3.60–7.05) 6.60 (5.88–7.83)	.014
8	Fitzpatrick skin types	II and III (n = 97, 51.05%) IV and V (n = 93, 48.95%)	4.80 (3.23–7.00) 5.90 (4.18–6.75)	.093
9	Pattern of facial melasma	Centrofacial (n = 155, 81.58%) Malar (n = 34, 17.89%) Mandibular (n = 1, 0.53%)	5.40 (3.70–7.20) 4.05 (2.86–6.08) 0.6	.024
10	Hormonal therapy	Yes (n = 73, 38.42%) No (n = 117, 61.58%)	5.60 (3.60–7.20) 5.30 (3.60–6.65)	.671
11	Sun exposure	Yes (n = 173, 91.05%) No (n = 17, 8.95%)	5.40 (3.60–6.78) 5.40 (3.60–5.95)	.982
12	Sun protection	Yes (n = 103, 54.21%) No (n = 87, 45.79%)	5.20 (3.30–6.60) 5.40 (3.60–6.80)	.416
13	Cosmetic use	Yes (n = 78, 41.05%) No (n = 112, 58.95%)	4.80 (2.80–6.33) 5.75 (3.94–7.43)	.003
14	Treatment for melasma	Yes (n = 117, 61.58%) No (n = 73, 38.42%)	5.40 (3.60–6.60) 5.40 (3.60–7.35)	.492
15	Dermatological Comorbidities	Yes (n = 114, 60.00%) No (n = 76, 40.00%)	5.63 (3.60–7.61) 4.80 (3.60–6.23)	.014
16	Non dermatological Comorbidities	Yes (n = 54, 28.42%) No (n = 136, 71.58%)	5.45 (4.05–6.63) 5.30 (3.60–6.79)	.436
17	Use of screen (mobile, TV, computer, and other electronic devices)	Yes (n = 168, 88.42%) No (n = 22, 11.58%)	5.25 (3.60–6.60) 6.35 (4.95–8.60)	.008

Dermatological comorbidities included bacterial/fungal infections, dermatitis, xerosis, vesicobullous disorders, and acne. Nondermatological comorbidities included hypertension, diabetes mellitus, chronic obstructive pulmonary disease, thyroid disorders, and chronic gastritis. P value was derived by running Mann–Whitney U test for dichotomous variables and Kruskal–Wallis H test for categorical variables with more than 2 categories. Frequency (n) and their respective percentage (%) are presented appropriately.

The overall median modified mMASI score was 5.40 (3.60–6.75). Most patients (168, 88.42%) had mild melasma. Twenty-one (11.05%) and 1 (0.53%) patients had moderate and severe melasma, respectively. The median mMASI score was compared across all sociodemographic and other possible risk factors (Table 1).

The mMASI score was weakly positively correlated with patient age, which was statistically significant (ρ = 0.240, n = 190, P = .001). The median score was significantly higher in the older group than in the younger age group (P = .024). There were no significant differences in the scores across gender, ethnicity, religion, family history, and Fitzpatrick skin types.

There was no difference in melasma severity between nulliparous and those women who had been pregnant at least once in the past. However, the order of parity was statistically significant. The mMASI score was significantly higher among women with parity greater than 3 compared to those with parity ≤3 (6.60 [5.88–7.83] vs 5.40 [3.60–7.05], P = .014).

All the patients in our study had facial melasma only. None of them had extrafacial involvement. Among these, centrofacial pattern was the most common (155, 81.58%). The severity was also highest in this pattern of melasma, and it was statistically significant (P = .024).

Likewise, patients using cosmetics at home were found to have significantly lower mMASI scores than those who did not use cosmetics (4.80 [2.80–6.33] vs 5.75 [3.94–7.43], P = .003). In the same way, 117 (61.58%) patients were receiving treatment for melasma for many months. However, their median mMASI score was not significantly different from those who were not getting any form of treatment.

Patients with other dermatological comorbidities (e.g., bacterial/fungal infections, dermatitis, xerosis, vesicobullous disorders, and acne) had significantly higher mMASI score compared to those without any skin diseases (5.63 [3.60–7.61] vs 4.80 [3.60–6.23], P = .014). However, there was no statistically significant difference with regard to other systemic comorbidities.

The severity of melasma was lower in patients who used to spend most of their time using devices with screen (e.g., mobile phone, computer, television), and it was statistically significant (5.25 [3.60–6.60] vs 6.35 [4.95–8.60], P = .008).

4. Discussion

This is a single-center cross-sectional study conducted in melasma patients visiting Dermatology OPD of a tertiary care center.

In our study, most participants with melasma (81%) were female, with a female-to-male ratio of 4:1. Similar ratio has been reported in other studies by Krupashankar et al^[11] and Achar et al.^[12] The female predominance of melasma has been consistently reported in few other studies by Hexsel et al,^[8] Yalamanchili et al,^[13] Kothari et al,^[14] Sarkar et al,^[15] and Morgaonkar et al.^[16] Majority of the patients (65.79%) belonged to age category of 31 to 55 years. This is comparable to the findings of a study by Yalamanchili et al,^[13] where the most commonly affected age group was 31 to 40 years. This is in contrast to the study by Morgaonkar et al,^[16] where the majority of cases were between 26 and 35 years of age. Likewise, the average age of patients was 40.2 ± 8.9 years and 37.2 ± 9.3 years in studies conducted by Hexsel et al^[8] and Krupashankar et al,^[11] respectively. These discrepancies among various studies could be explained partly on the basis of different study population, genetics, environmental factors, diet, and lifestyle in different regions of the world.

In our study, the median mMASI score was 5.40, which is comparable to the mean score of 5.7 reported by Yalamanchili et al.^[13] However, higher average scores (6.696 and 8.050) have been reported by Sarkar et al^[15] at different sites in India.

Sixty-two percent of the melasma cases in our study had a positive family history. This is in line with the findings of Hexsel et al,^[8] who reported a positive family history of melasma in 64% of the cases. However, the familial prevalence of melasma was relatively lower in the study by Yalamanchili et al^[13] (18%), Kothari et al^[14] (27.7%), Krupashankar et al^[11] (31%), Sarkar et al^[15] (20%), and Achar et al^[12] (33.33%). This difference may be due to different genetic and environmental factors that may potentially play a role in melanogenesis among different populations.

In the present study, the centrofacial pattern was the most common (81.58%). This is supported by Guinot et al^[6] and Achar et al,^[12] who reported similar patterns of 76% and 55.4%, respectively. However, the malar pattern was more common in other few studies.^[13,14] These differences could be due to difference in study sample and size across different studies.

Electronic devices (e.g., mobile phones, computers, televisions, and tablets) are essential elements of modern life. People spend a significant amount of time using digital devices. Owing to this, there is growing public interest in the potential effects of visible light emitted from these gadgets. The blue light generated by them typically falls in the range 420 to 490 nm. An in vivo study conducted by Austin et al¹⁷ showed that short-term exposure of skin to light produced from screens can produce reactive oxygen species, leading to apoptosis and necrosis. This can potentially contribute to melanogenesis and pigmentation. However, the long-term effects of repeated exposure to such light and association with melasma remain unknown.^[17–19] In contrast, an experimental study by Duteil et al^[20] showed that short-term exposure to blue light emitted by electronic devices does not worsen melasma. Likewise, in our study, the severity of melasma was not significantly higher in patients who used electronic devices most of the time. There is insufficient evidence to describe the definite effects of screen light on the human skin. Therefore, further studies are needed to describe the effects of screen light on pigmentation and melanogenesis in human skin.

There are a few limitations of our study to be mentioned. This is a single-center study with small sample size. Moreover, the study sample only included patients with melasma visiting the Dermatology OPD of a hospital. So, all the findings may not be generalizable to a larger population. Moreover, there was a potential recall bias among participants especially while reporting past history of melasma, pregnancy/parity, family history of melasma, any treatment received, recent cosmetics used, and exposure to screens.

5. Conclusion

In our study, most of the cases had mild melasma. The melasma severity score was significantly higher in older age, in women having parity of more than 3, centrofacial pattern of melasma, and presence of dermatological comorbidities. However, severity was significantly lower in those who used cosmetics at home. Likewise, the use of screens was not associated with increased risk of melasma. Further studies are required to validate these findings.

Author contributions

Conceptualization: Sunil Shakya, Bishnu Deep Pathak, Ramesh Lamichhane.

Methodology: Sunil Shakya, Bishnu Deep Pathak, Ramesh Lamichhane.

Project administration: Sunil Shakya, Bishnu Deep Pathak.

Supervision: Sunil Shakya.

Writing—review & editing: Sunil Shakya, Bishnu Deep Pathak, Ramesh Lamichhane, Bhuwan Ghimire, Sameeksha Devkota, Sandesh Ghimire, Prosess Shrestha, Sajana Acharya, Sunil Baniya, Kanchan Bogati, Indra Dev Pathak, Bishal Dhakal.

Formal analysis: Bishnu Deep Pathak.

Writing—original draft: Bishnu Deep Pathak, Ramesh Lamichhane.

Investigation: Ramesh Lamichhane, Bhuwan Ghimire, Sameeksha Devkota, Sandesh Ghimire, Prosess Shrestha, Sajana Acharya, Sunil Baniya, Kanchan Bogati, Indra Dev Pathak, Bishal Dhakal.

Data curation: Bhuwan Ghimire, Sameeksha Devkota, Sandesh Ghimire, Prosess Shrestha, Sajana Acharya, Sunil Baniya, Kanchan Bogati, Indra Dev Pathak, Bishal Dhakal.