Late-Onset Rheumatoid Arthritis

Late-onset rheumatoid arthritis (LORA), also called elderly-onset RA, is rheumatoid arthritis with first symptom onset at or after 60–65 years, as distinct from young-onset RA growing old — a distinction that must be made explicitly in the answer.

It accounts for roughly 10–33% of all RA. The female preponderance of young-onset disease is lost — the sex ratio approaches 1:1.

Pathy's notes rheumatoid arthritis as a recognised cause of secondary osteoporosis and as a factor in FRAX, and RA joint pain as a classical driver of immobility and frailty in older people.

The same autoimmune synovitis as classical RA — citrullination of self-proteins, anti-citrullinated peptide antibody formation, T- and B-cell activation, and cytokine-driven pannus formation with TNF-α, IL-1 and IL-6.

Immunosenescence shapes the phenotype: thymic involution, expansion of CD4+CD28− senescent T cells, telomere shortening and "inflammaging" produce a more acute-onset, cytokine-driven, seronegative and polymyalgic picture.

HLA-DRB1 shared-epitope association is weaker than in young-onset disease.

Three recognised subsets: (i) a classical RA-like polyarthritis; (ii) a PMR-like syndrome with proximal girdle stiffness; (iii) RS3PE — remitting seronegative symmetrical synovitis with pitting oedema of the hands, which is strongly age-associated, HLA-B7 linked, exquisitely steroid-responsive, and may herald occult malignancy.

Presentation is often functional: sudden inability to dress, grip or walk, presenting as "off legs" or acute functional decline rather than as joint complaint.

Extra-articular features when present: interstitial lung disease, anaemia of chronic disease, secondary Sjögren's syndrome, vasculitis, Felty's syndrome, scleritis, pericarditis, and amyloidosis. Cervical spine involvement with atlanto-axial subluxation is a specific anaesthetic hazard.

Rheumatoid factor and anti-CCP — anti-CCP is far more specific, since RF rises with age and is positive in up to 10–25% of healthy older people, making a low-titre RF alone almost meaningless in this age group.

ESR, CRP, full blood count (anaemia of chronic disease, thrombocytosis), renal and liver function — the latter two also determine DMARD choice.

Radiographs of hands and feet for periarticular osteopenia, joint space narrowing and marginal erosions; ultrasound or MRI for early synovitis and erosion detection.

Pre-treatment screen: chest radiograph, hepatitis B and C serology, tuberculosis screening (crucial in India before any biologic — Mantoux/IGRA plus chest X-ray), and vaccination status.

2010 ACR/EULAR classification criteria (score ≥6/10 from joint involvement, serology, acute-phase reactants and symptom duration ≥6 weeks) are used, though they perform less well in seronegative late-onset disease.

Differential diagnosis is the crux: polymyalgia rheumatica (no true synovitis, no erosions, responds to 15 mg prednisolone), calcium pyrophosphate deposition disease / pseudogout, polyarticular gout, paraneoplastic arthritis, viral arthritis, hypothyroidism, and erosive osteoarthritis of the hands.

Treat-to-target applies equally in old age — aim for remission or low disease activity using DAS28, with review every 1– 3 months. Age alone is not a reason for therapeutic nihilism, since uncontrolled RA causes disability, sarcopenia, osteoporosis and excess cardiovascular death.

Methotrexate remains the anchor drug, starting 7.5–10 mg weekly with folic acid. Pathy's cautions that there is a natural 30% decrease in glomerular filtration rate with ageing, in addition to further potential renal insults, so caution must be taken with dosing methotrexate in older patients with renal impairment. Monitor full blood count, liver function and creatinine.

Alternative csDMARDs: leflunomide, sulfasalazine, hydroxychloroquine (useful in mild disease and safest in the frail; needs retinal screening).

Glucocorticoids give rapid control as bridging therapy at the lowest effective dose for the shortest time; in older adults the cumulative harms — osteoporosis, diabetes, infection, cataract, skin fragility — are magnified. Osteoporosis and gastrointestinal ulcer prophylaxis should be employed in all patients treated with oral steroids to minimise potentially devastating complications (Pathy's, on steroid use in older adults).

Biologic DMARDs — TNF inhibitors, abatacept, tocilizumab, rituximab — are effective in older adults, though with a higher absolute infection risk. Abatacept has a comparatively favourable infection profile in the elderly.

JAK inhibitors (tofacitinib, baricitinib, upadacitinib) are effective orally, but the ORAL Surveillance safety signal restricts use in those over 65 with cardiovascular risk factors or a smoking history, because of increased major adverse cardiovascular events, venous thromboembolism and malignancy.

NSAIDs should be minimised — they appear on the AGS Beers Criteria and cause bleeding, renal impairment and heart failure in this age group.

Comprehensive care: physiotherapy and occupational therapy for joint protection and assistive devices, exercise to counter sarcopenia, cardiovascular risk assessment (RA is an independent cardiovascular risk factor), osteoporosis screening and treatment, vaccination (influenza, pneumococcal, herpes zoster — inactivated preparations only on immunosuppression), and management of depression and caregiver burden.

Prognosis: seropositive, erosive late-onset RA behaves as aggressively as young-onset disease and causes greater functional loss because of lower physiological reserve; seronegative and PMR-like variants often have a milder, more steroid-responsive course.