3. Results
The clinical and ECG characteristics of the patients with RA are summarized in Table 1. The mean age of the patients was 64.7 ± 12.3, and the majority were female (289 patients, 85.0%). The mean body mass index (BMI) was 22.4 ± 3.8 kg/m2. Hypertension, diabetes, dyslipidemia, and current smokers were found in 126 (37.1%), 32 (9.4%), 133 (39.1%), and 116 (34.1%) patients, respectively.
The median duration of RA was 3,563 days (25th to 75th percentile: 1,733–7,547 days). The majority of patients with RA were RF-positive (75.0%) and ACPA-positive (77.9%). The VAS, CDAI, SDAI, DAS28-ESR, DAS28-CRP, and HAQ scores are provided in Table 1. Patient VAS scores were significantly higher than clinician VAS scores (24.5 ± 23.4 vs. 8.7 ± 11.5, p < 0.0001). In the laboratory data, the mean ESR and CRP level of the included patients were 20.6 ± 17.2 mm/h and 0.44 ± 1.06 mg/L, respectively. DMARDs were used by 90.0% of the patients, while 68.2% received methotrexate (MTX), 54.7% received biologic agents, 26.1% received prednisolone treatment, and 36.2% received more than two types of RA drugs (Table 1). Patients receiving prednisolone treatment showed a longer QTc interval than that of patients not receiving prednisolone treatment (424.2 ± 20.4 ms vs. 418.5 ± 17.4 ms, p = 0.014). No difference in the QTc interval was observed between those with and without MTX or biologic agent treatments (Supplementary material).