Document Type : Research Article
Background: The most noticeable part of human body is face. The obvious boundaries on the skin known as Pigmentary Demarcation Lines (PDL) found over face and have clear borders of abrupt transition between more hyper-pigmented skin and areas of normal skin pigmentation due to differences in melanocyte distribution that may be influenced by multiple factors. Facial pigmentary demarcation lines (PDL) directly reflect on patient’s physical appearance and self-image as they may contribute to dysmorphism and even central to depressive illness in susceptible individuals posing cosmetic concern for the patient and a challenge for dermatologist. Therefore, it is important for early identification and management of facial skin disorders. Until now, nine different types of PDLs have been described which are designated as Type A to I of which Type F to H PDLs are most common on the face. Etiology involving the whole spectrum of PDL continues to be an enigma and needs further research among Indian population.
Materials and Methods: Total 304 patients between 15 to 75 years of age range were included in study lead between May 2018 to May 2020 after thorough examination for inclusion and exclusion criteria, informed consent and Ethics committee approval. Statistical analysis was done using descriptive and inferential statistical approach using Chi-square test and Fisher’s exact test and p value was calculated and considered to be significant if <0.05.
Results: Out of 304 study subjects the frequency of facial PDL type H (50.65%) was most common than type G (29.60%) and type F (19.73%) with male predisposition (79.60%) with agricultural occupations (59.86%) than females and with significant family history from father (41.44%). Most of the present study subjects were of Fitzpatrick skin type IV (50.01%) with hyper-pigmented macules (12.5%) and shown unilateral PDL symmetry (58.22%) with sharp PDL line margins (81.25%). The most common aggravating factor was prolonged exposure to sun light (56.90%) and most of (25.98%) the subjects experienced periorbital melanosis at different times. Diabetes (38.15%) and hypertension (29.60%) were the most common co morbidities observed in study subjects. Using Fishers exact test, p value was calculated and it was found to be highly significant (p=0.003).
Conclusion: Present study pronounces the incidence of facial PDL (types F-H) are sharply common especially amongst the males who are in agricultural occupations with prolonged sun exposure and with other co morbidities like diabetes, hypertension and tuberculosis. In females the prevalent type was Type H PDL during and after pregnancy. The agricultural occupations with prolonged sun exposure, diabetes, hypertension, tuberculosis and positive paternal family history were shown strong correlation with facial PDL among Indian population irrespective of gender and it was found to be highly significant (p=0.003).