Elderly-onset rheumatoid arthritis (EORA) is a distinct clinical entity defined as the onset of rheumatoid arthritis (RA) in individuals aged over 60 years. EORA presents unique clinical features, including a more equitable distribution of sexes, a potential predilection for male involvement, a higher incidence of acute onset characterized by constitutional symptoms, a propensity for systemic manifestations, elevated sedimentation rates at disease onset, a reduced occurrence of rheumatoid factor positivity, increased titers of anti-citrullinated protein antibodies, a preference for involvement of large joints, elevated disease activity, the presence of bone erosions, and heightened patient disability.
1. Introduction
Rheumatoid arthritis (RA) is a systemic, inflammatory disorder that predominantly affects women, with the peak incidence occurring between the ages of 30 and 50, and the average onset age is 55
[1]. Elderly-onset rheumatoid arthritis (EORA) is typically characterized by disease onset after the age of 60. Conversely, “young-onset rheumatoid arthritis” (YORA) describes RA with a more typical presentation at a younger age
[1]. Approximately one-third of RA cases develop in individuals aged over 60, and the prevalence increases with advancing age, particularly into the eighth decade
[1][2][3][1,2,3].
Historically, earlier studies generally concluded that EORA was a milder form of the disease with a favorable prognosis
[2][4][5][6][2,7,8,9]. However, recent research has revealed a more concerning disease activity and severity, as well as poorer clinical, functional, and radiographic outcomes in EORA, compared to YORA
[7][10]. Some authors have postulated that factors such as seropositivity
[8][9][11,12], longer disease duration
[10][13], and less intensive treatment
[6][9] may contribute to the potentially worse prognosis of EORA. Nevertheless, the fundamental question of whether EORA and YORA genuinely represent distinct prognostic entities or variations within the broader RA spectrum remains unanswered to date.
In the initial stages of EORA management, non-steroidal anti-inflammatory drugs (NSAIDs) are not typically the first-line treatment choice, because seniors are much more prone to develop side effects due to NSAIDs, and the use of NSAIDs is in reality contraindicated to the majority of seniors due to comorbidities. Disease-modifying antirheumatic drugs (DMARDs), frequently methotrexate, are introduced immediately after the diagnosis is made. In cases where elderly patients demonstrate resistance to conventional DMARD therapy, the introduction of biological or targeted synthetic DMARDs becomes a viable treatment option.
In response to the evolving challenges in RA management, the burgeoning field of RA nano therapies holds significant promise. By overcoming the limitations of conventional treatments through advancements in nanotherapeutic techniques, particularly in drug delivery systems, these innovations might offer precise and targeted solutions
[11][14].
2. Differences between EORA and YORA Diseases
EORA markedly differs from YORA in several key aspects (Table 1).
Table 1.
Comparison of main characteristics of patients with EORA and YORA.
Characteristics |
EORA |
YORA |
Age of onset |
after 65 years |
30–50 |
Prevalence |
2% |
0.5–1% |
Female/male ratio |
1/1 or more men |
3/1 |
Onset |
[13][41], is characterized by an elderly onset, an acute onset, symmetrical synovitis and tenosynovitis, pitting edema of the dorsum of the hands and feet, negative RF and ACPA status, the absence of bone erosion, and an excellent prognosis, with low-dose corticosteroid therapy and spontaneous remission within 3–18 months
[14][15][42,43]. Interestingly, in these subgroup cases, high HLA-B27 positivity has also been reported
[12][15]. To distinguish RS3PE syndrome from EORA, it is essential to assess not only intra-articular but also extra-articular lesions using musculoskeletal ultrasound (MSUS).
Sometimes it is hard to differentiate EORA from PMR and RS3PE (
Table 2), but it is important to note that the differential diagnosis of EORA extends beyond PMR and RS3PE syndrome. Other conditions, such as osteoarthritis, spondyloarthropathy, hypertrophic osteoarthropathy, sarcoidosis, connective tissue diseases, systemic vasculitis, paraneoplastic syndromes, crystal arthropathies (such as gout, pseudogout, or chronic pyrophosphate arthropathy), and infectious arthritis (including viral, especially hepatitis C, and bacterial infections, like septic arthritis), should also be considered and ruled out via the diagnostic process.
Table 2.
Different clinical and laboratory features of EORA, PMR, and RS3PE.
Characteristics |
EORA |
PMR |
RS3PE |
Proximal joints |
+ |
+++ |
− |
Peripheral joints |
+++ |
+ |
+++ |
Tenosynovitis |
++ |
+/− |
+++ |
Edema |
+ |
+ |
+++ |
RF+ |
+/− |
− |
− |
High ESR |
+ |
+++ |
+ |
acute and infectious-like |
gradual |
Number of joints involved |
may be oligoarticular |
polyarticular |
Sites involved |
large/proximal joint |
small joints of the hands and feet |
Fatigue, weight loss |
more prominent |
less prominent |
Genetic predisposition |
HLA-DRB1∗ 01 |
HLA-DRB1*04 |
Rheumatoid factor |
lower incidence |
higher incidence |
Titer for ACPA |
higher |
lower than EORA |
Subcutaneous nodules |
less frequent |
more frequent |
Pauci-immune fibroid synovial pathotype |
less frequent |
more frequent |
Bone erosions |
more frequent |
frequent |
Elevated ESR/CRP |
more frequent |
frequent |
Higher WBC, ANC |
more frequent |
frequent |
Lower PLR, NLR |
more frequent |
frequent |
Higher IL6, lower TNFα |
more frequent |
less frequent |
Higher DAS28, CDAI, SDAI |
more frequent |
frequent |
Higher ultrasound features: ST, PDS, SHC |
more frequent |
frequent |
Clinical form |
classical RA PMR-like form RS3PE s/m like form |
classical RA |
Comorbidity |
more frequent |
less frequent |
Prognosis |
worse |
good or worse |