Using Retrospective Cohort Method to Evaluate the Risk of Peripheral Artery Disease (PAD) in Females with Pelvic Inflammatory Disease (PID)

[[abstract]]Background: Pelvic inflammatory disease is a common inflammatory disease in women. The inflammatory response can be persistent and systemic, and long-term systemic inflammation is considered as the primary cause of cardiovascular disease. Peripheral arterial disease is the third among cardiovascular diseases associated with atherosclerosis, with its risk of death due to myocardial infarction, stroke, or cardiovascular disease being more than three times that among individuals of the same age group, making it an important health issue. Pelvic inflammatory disease has been reported to be associated with cardiovascular disease; hence, it is likely that pelvic inflammatory disease and peripheral arterial disease will be accompanied by cardiovascular disease. This issue has not yet been reported in Taiwanese population. Therefore, this study investigated the association between pelvic inflammatory disease and peripheral arterial disease. Methods: This retrospective cohort study was conducted using Taiwan National Health Insurance Research Database. The pelvic inflammatory disease group consisted of 66,846 newly diagnosed females aged 13–50 years recruited from 2000 to 2010, and the nonpelvic inflammatory disease group consisted of the same number of control subjects with a propensity score matched to 1:1 ratio and matched according to age, date of disease diagnosis, and associated comorbidities. Both groups were monitored till the end of 2011, and the incidence of peripheral arterial disease was determined. Data were analyzed using single variable and variable Cox proportional hazards regression model to assess crude hazard ratio, adjusted hazard ratio, and 95% confidence interval (CI). All statistical analyses were conducted using SAS software version 9.4 (SAS Institute Inc., Cary, NC, USA), with p values