Background Biologics have dramatically changed the treatment of rheumatoid arthritis (RA). In recently years, several biologics have become available, and about half of these drugs are delivered by subcutaneous (s.c.) injections. However, the pain caused by s.c. injection may become a problem in some cases.
Objectives We aimed to evaluate the severity of s.c. injection-related pain in patients receiving biologics via these injections.
Methods The visual analogue scale (VAS) scale was used to assess the impact of the s.c. injection-related pain. The VAS is a 10-cm horizontal line with pain descriptors. Patients indicated the magnitude of injection-associated pain by allocating a score ranging from 0 (no pain) to 100 (most intolerable pain). Each patient gave assessments for a maximum of 4 types of s.c. injections. Etanercept (ETN), adalimumab (ADA), and golimumab (GOL) were the selectable drugs that the patients received at present and/or in the past, and s.c. of influenza vaccination (IV) was used as a control.
Results A total of 123 RA patients (mean age, 59 years; range, 30-84 years) participated in this study. There were 104 women (84.6%). The number of patients who provided VAS scores for IV, ETN, ADA, and GOL injections was 123, 70, 60, and 17, respectively. The VAS scores (median, IQR) were as follows: IV, 26, 15-46; ETN, 41, 22.5-57; ADA, 59, 30-82.7; and GOL, 35, 27-41. After adjustment using the VAS ratio (each biologics/IV), the VAS ratio (median, IQR) for the selectable drugs were as follows: ETN/IV, 1.140, 0.736-2.189; ADA/IV, 1.627, 0.973-3.898; and GOL/IV, 0.949, 0.800-1.125. The VAS score of GOL was about the same as that of IV, and s.c. injections of GOL seemed to be the least painful (GOL vs. ADA, p = 0.0052 and ETN vs. ADA, p = 0.0060). However, most of the patients answered that the insertion of the biologic drugs, not the sting of the needle, caused the maximum discomfort.
Conclusions Patient-orientated evaluations of pain caused by s.c. injections showed that injections of GOL caused less pain than those of the other biologics. Although evaluations of injection-associated pain differ with each patient, more comfortable s.c. injections are necessary to improve patient convenience and increase compliance with RA treatment.
Disclosure of Interest None Declared