Matched case-control study to examine association of psoriasis and migratory glossitis in India.

BACKGROUND

Psoriasis is a multifactorial disease. Genetic and environmental factors, which determine the disease epidemiology and clinical spectrum, are heterogeneous in different populations. A few case-control studies from other countries have shown an association between psoriasis and migratory glossitis (MG). The characteristics of the association (e.g. relationship with gender, severity of psoriasis, early- versus late-onset psoriasis, etc.) have not been clearly defined.

AIM: To investigate the association of psoriasis and MG by conducting a matched case-control study in India.

METHODS

The study was conducted on 600 patients with psoriasis and 800 age- and sex-matched controls. Patients were examined for oral lesions and psoriasis severity was assessed by overall severity index (OSI) and psoriasis area and severity index (PASI). We compared the proportions of patients and controls with oral lesions, proportions of male and female patients who had MG, psoriasis severity scores of patients with or without MG, and proportions of early- and late-onset psoriasis patients who had MG.

RESULTS

Significantly, more patients had oral lesions than controls (P=0.0013). There was a strong association between psoriasis and MG (P<0.0001). MG and fissured tongue (FT) occurring in the same patient were also strongly associated with psoriasis (P=0.0003). There was a weak association of psoriasis with FT (P=0.0456). Significantly, higher proportion of male patients had MG compared to female patients (P=0.0246). Patients with MG had more severe psoriasis compared to those without the tongue lesions (P<0.0001). Similar proportions of patients with type 1 and type 2 psoriasis had MG (P=0.7268).

CONCLUSIONS

The results suggest that MG is a rare manifestation of psoriasis which occurs more commonly in male patients and in those with severe disease, and that it occurs with equal frequency in early- and late-onset psoriasis. It will be interesting to follow those patients who have MG, but not psoriasis, to see whether they develop psoriasis phenotype in future.