Digoxin use and following risk of psoriasis: A population‐based cohort study in Taiwan

This study examined the association between digoxin use and subsequent psoriasis risk using a population‐based database in Taiwan. This cohort study enrolled 15 545 digoxin users and 15 545 propensity score‐matched non‐users from the Taiwan National Health Insurance Research Database. Each patient was independently followed up for 5 years to confirm whether they had been diagnosed with psoriasis. Cox proportional hazard regression was used to estimate psoriasis risk among digoxin users. Subgroup and sensitivity analyses were also performed. The psoriasis incidence rates were 3.02 and 2.27 per 1000 person‐years among digoxin users and non‐users, respectively. After adjustment for confounders, psoriasis risk was significantly higher among digoxin users than among non‐users. Notably, in most subgroup analyses, digoxin use tended to increase psoriasis risk, particularly among patients with heart failure, diabetes, hypertension and hyperlipidaemia. Moreover, significantly increased psoriasis risk was noted over 2, 3, 4 and 5 years of digoxin use. In conclusion, our findings confirm that digoxin use increases subsequent psoriasis risk. Thus, physicians should be aware of this association and accordingly estimate the risks and benefits of digoxin use. Nevertheless, some patient variables, such as body mass index and obesity, were unavailable in this study. The findings in this study should be elucidated carefully because the potential effects of these factors could not be considered.