Late onset rheumatoid arthritis: clinical and laboratory comparisons with younger onset patients.

We aimed to compare the clinical and laboratory profiles of the patients presenting late onset rheumatoid arthritis (LORA) with younger onset rheumatoid arthritis (YORA) patients. During the period between January 1995 and December 2004, 124 patients with LORA were identified from a retrospective chart review of inpatients and outpatients. They were compared with 150 YORA patients examined during the same period including their clinical and laboratory findings. The mean ages of the patients with LORA and YORA were 71.7+/-5.9 years, and 52.1+/-11.5 years, respectively. The gender ratio (female/male) was 1.48 in LORA and 2.85 in YORA (p = 0.012). The average ages of the disease onset were 42.2+/-10.4 years in YORA and 68.4+/-4.6 years in LORA. The duration of the diagnosis was longer in LORA than in YORA (20.7+/-14.3 months versus 10.3+/-6.2 months, p < 0.001). Rheumatoid arthritis (RA) duration was shorter in LORA than in YORA (43.5+/-64.4 months versus 126.3+/-101.0 months, p < 0.001). Although LORA patients had more significant frequent shoulder joint involvements (p < 0.001), proximal interphalangeal (PIP), metacarpophalangeal (MCP), elbow, metatarsophalangeal (MTP) and ankle involvements were common in YORA. Wrist, knee and hip involvements were not different in the groups. Classical rheumatoid hand deformities, interstitial lung disease and Sjögren's syndrome (SS) were significantly lower in LORA than in YORA. LORA patients had more common weight loss, myalgia, lymphadenopathy, polymyalgia rheumatica (PMR)-like syndrome and neuropathy. The frequencies of RF, ANA, anti-SSA/Ro and anti-SSB/La positivities were lower in LORA than in YORA, whereas elevated erythrocyte sedimentation rates (ESR), C-reactive protein (CRP) and anemia associated with chronic disease were higher in LORA. Patients with LORA, according to the accepted international criteria, present with different clinical and laboratory profiles when compared with younger patients. These results suggest that age may influence the presentation of RA at onset.