Objective: This study aimed to evaluate the relationship between telomere length and rheumatoid arthritis (RA).
Methods: We performed a meta-analysis of studies comparing the telomere length in RA patients and healthy controls, and conducted subgroup analysis based on ethnicity, age-matched status, study quality, sample type, assay method, subject number, and shared epitope (SE) status.
Results: Nine studies from seven articles, with 388 RA patients and 362 controls, were included. Meta-analysis showed that the telomere length was significantly shorter in all individuals of the RA group than in those of the control group (SMD = -0.833, 95 % CI = -1.332 to -0.334, p = 0.001). Stratification by ethnicity showed significantly shortened telomere lengths in both mixed and age-matched Caucasian populations with RA (SMD = -1.415, 95 % CI = -1.709 to -1.120, p < 1.0 × 10-8; SMD = -0.658, 95 % CI = -1.187 to -0.0.128, p = 0.015). The telomere length was significantly shorter in the RA group than in the age-matched control group; however, this was not the case in the RA group that was not age-matched (SMD = -1.070, 95 % CI = -1.489 to -0.650, p = 5.7 × 10-7; SMD = 0.155, 95 % CI = -0.119 to 0.429, p = 0.267). Stratification by SE status revealed a significantly shortened telomere length in the SE-positive group, but not in the SE-negative group (SMD = -1.033, 95 % CI = -1.398 to -0.768, p < 1.0 × 10-8; SMD = -0.967, 95 % CI = -2.382 to 0.449, p = 0.181). In addition, the telomere length was significantly shorter in the SE-positive RA group than in the SE-negative RA group (SMD = -0.415, 95 % CI = -0.699 to -0.131, p = 0.004).
Conclusions: Our meta-analysis demonstrated that the telomere length was significantly shorter in patients with RA, and was significantly more so in the SE-positive group than in the SE-negative group.
Keywords: Autoimmune diseases; Biological markers; Etiology; HLA antigens; Risk factors.