Systemic sclerosis increases the risks of deep vein thrombosis and pulmonary thromboembolism: a nationwide cohort study

Abstract

Few Asian studies have evaluated the risks of deep vein thrombosis (DVT) and pulmonary thromboembolism (PTE) in patients with SSc. We conducted a nationwide population-based cohort study to evaluate how SSc affected the incidence of DVT and PTE in Taiwan. We identified patients with an SSc diagnosis in Taiwan between 1998 and 2010 using the Catastrophic Illness Patient Database and the National Health Insurance Research Database. Each SSc patient was frequency matched to four control patients based on age, sex and index year and all patients were observed from the index date until the appearance of a DVT or PTE event or 31 December 2010. We calculated the hazard ratios and 95% CIs of DVT and PTE in the SSc and comparison cohorts using the Cox proportional hazards regression model. We observed 1895 SSc patients and 7580 control patients for ∼10,128 and 46,488 person-years, respectively. The mean ages of the SSc and comparison cohorts were 50.3 and 49.9 years, respectively. After adjusting for age, sex and co-morbidities, the risks of DVT and PTE among the SSc patients were 10.5- and 7.00-fold higher than those of the control patients. The probability of developing DVT and PTE increased in the years following the SSc diagnosis. SSc patients exhibited a significantly higher risk of developing DVT and PTE compared with the general population. Thus multidisciplinary teams should guide the assessment, treatment and holistic care of SSc patients.