Late onset rheumatoid arthritis in the elderly: features of the course of the disease

Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology characterized by chronic erosive arthritis (synovitis) and systemic internal organ damage. The pathology is associated with decreased quality of life and functional capabilities as well as increased disability and mortality.

According to the results of a Russian epidemiological study, Rheumatoid arthritis affects about 800,000 people. A similar prevalence of the disease is observed in European countries. There are 2.5 times more women with RA than men.

Rheumatoid arthritis of the knee https://touchofhealthmedical.com/orthopedics/knees-pain/arthritis-knee/ can develop at any age. According to the classification of the World Health Organization, up to 45 years old is young, 45 to 59 years old is mature, 60 to 74 years old is old, 75 to 89 years old is senile. Persons over the age of 90 are recognized as long-livers. The prevalence of the disease increases with age and reaches its peak at the age of 70-79. In the United States, for example, RA affects 2% of the population over 60 years of age and up to 5% of women over 70 years of age. According to an epidemiological study conducted in Spain, the prevalence of RA over 60 years of age in men was 9.1 cases per 100,000 people, in women 14.5 cases.

Depending on the age of onset, RA is distinguished:

• RA early onset - up to 45 years of age;
• Intermediate-onset RA - from 45 to 60 years of age;
• Late-onset RA - after the age of 60.
• Some authors classify RA with the onset at the age of 60-65 years and older as old-age RA.

Given the trend toward longer life expectancy and an aging population, we can assume that the prevalence of late-onset RA will only increase.

Despite advances in rheumatology, it has not been established whether onset at an advanced age is a predictor of poor prognosis, whether late onset affects the severity of clinical manifestations and the rate of radiological (erosive) changes. Literature data in this respect are ambiguous.

It is known that the clinical course of Rheumatoid arthritis of the Spine https://touchofhealthmedical.com/orthopedics/spine-pain/arthritis-spine/ in elderly patients is influenced by genetic, immunological and hormonal factors. Aging is a physiological process characterized by impaired immune system functioning. In particular, it is a decrease in proliferation of T-cells and immune response. At the same time, the response to autoantigens increases, the process of recognition of own and foreign antigens becomes less accurate. The balance between T-regulatory cells and increased levels of proinflammatory cytokines is disturbed.

RA of late onset is characterized by an acute debut, rapidly emerging polyarthritis, and marked constitutional symptoms such as fever, weight loss, rapid fatigue, and weakness.

In contrast to early onset, late-onset RA shows more even gender differences with respect to morbidity. The ratio of women to men is 2:1.

Currently, three main clinical variants of the course of late-onset RA have been distinguished. The first, the most common, is similar to the classical variant of RA, which is characterized by polyarthritis, morning stiffness, detection of rheumatoid factors. In such patients, rapid structural damage of the joints with the formation of erosive arthritis within the first year of the disease is observed. The second clinical variant symptomatically resembles rheumatic polymyalgia, often involving large joints, in particular the shoulder. It is characterized by an acute onset with pronounced constitutional manifestations. In this case, the rheumatoid factor in the blood is not detected. Symmetrical polyarthritis with involvement of proximal interphalangeal and metacarpophalangeal joints of the hands develops within several months from the beginning of the disease. The third clinical variant has similarities with RS3PE (Remitting Seronegative Symmetrical Synovitis with Pitting Edema) syndrome. RS3PE syndrome was first described by D.J. McCarty et al. in 1985: acute onset with the development of symmetrical polyarthritis and marked bilateral mild edema of the hands. On laboratory examination - rheumatoid factor seronegativity. In this clinical variant of RA, the outcome is more favorable, radiological progression is slow, and the rate of remission is high.

The results of studies evaluating the clinical and radiological characteristics of patients depending on their age at the onset of RA are contradictory. In particular, a number of studies indicated higher rates of disease activity, including erythrocyte sedimentation rate and C-reactive protein levels, in patients over 60 years of age. L. Innala et al. found that acute-phase inflammatory parameters (erythrocyte sedimentation rate and C-reactive protein level) were significantly higher in patients with disease onset at an older age. Disease Activity Score 28 (DAS 28) after six and 12 months of follow-up was also higher in the late-onset Rheumatoid Arthritis group. These findings are inconsistent with the results of other studies. In them, patients with late-onset disease had a better prognosis. The discrepancy in the results may be due to the difficulties in the differential diagnosis of late-onset RA and to the absence of strict classification criteria for RA in earlier studies (1970-1990).

According to other researchers, the clinical course of early rheumatoid arthritis of the Foot https://touchofhealthmedical.com/orthopedics/foot-and-ankle-pain/arthritis-foot-and-ankle/ is independent of the age of patients at the onset of the disease. For example, in a study conducted by D.Y. Chen, no statistically significant differences in DAS 28, serum levels of C-reactive protein, and the number of erosions in the hands and feet were found in the groups with early-onset and late-onset RA. Similar data were obtained by T.C. Tan et al.: DAS 28 values and the severity of radiological progression did not differ significantly in the age groups studied. It should be noted that a number of authors described a classical picture of RA developed in elderly patients - an acute onset followed by a decrease in clinical activity. According to T.C. Tan et al. data, at the time of diagnosis DAS 28 was significantly higher in elderly patients than in younger patients. However, after six months of follow-up, no significant differences between the groups were observed. In a prospective three-year study by T. Krams et al. in their follow-up of patients of different age subgroups revealed a significantly higher rate of radiological progression in elderly and middle-aged patients compared to younger patients. The authors noted higher levels of acute-phase inflammatory indices in the elderly at the onset of the disease and the possibility of correlation of these indices with the rate of progression of destructive changes before anti-inflammatory therapy. When comparing acute-phase inflammatory indices and disease activity according to CDAI (Crohn's Disease Activity Index), SDAI (Simplified Disease Activity Index - SDAI), DAS 28 in a two-year prospective study, K. Murata et al. recorded a statistically significant increase in the studied indicators in elderly patients at the onset of the disease. The elderly also had a greater number of painful joints and destructive changes as measured by hand and foot radiographs. However, after two years of follow-up, the remission rate was not significantly different in the studied groups. C-reactive protein level and erythrocyte sedimentation rate were still higher in late-onset RA patients. However, the dynamics of the indices were not statistically significant. Despite control of disease activity, the rate of radiological progression was significantly higher in patients with late-onset RA. Consequently, in elderly patients it is insufficient to control disease activity to protect bone tissue from the negative effects of RA.