A clinico-demographic study of 344 patients with lichen planus pigmentosus seen in a tertiary care center in India over an 8-year period

Background Lichen planus pigmentosus (LPP) is an acquired disorder of hyperpigmentation affecting certain racial and ethnic groups. Objective To retrospectively analyze the demographic and clinical characteristics of LPP. Methods Clinical and demographic records of all LPP patients attending our pigmentary clinic from January 2011 to June 2018 were reviewed. Results Data of 344 LPP patients (229 females) were analyzed. Affected females had significantly higher age at onset (P < 0.002) but lesser disease duration at presentation (P < 0.001) as compared to males. Significant positive correlation between body surface area involvement and disease duration was observed (r = 0.72). Personal history of atopy and accompanying autoimmune diseases were observed in 49 (14.24%) and 45 (13.08%) patients, respectively. Observed morphological patterns of LPP included diffuse (n = 193, 56.1%); reticular (n = 45, 13.1%); blotchy (n = 41, 11.9%); and follicular (n = 28, 8.1%). All the patients had a chronic and indolent course of disease with approximately half (49.2%) reporting satisfactory improvement with treatment. Conclusion This is the largest clinico-demographic study till date on LPP. A longer disease duration was associated with more widespread disease. Although the disease improved over time as per patient and physician global assessment, a complete clearance was rarely attained.