Rheumatoid Arthritis and the Kidney: Uneasy Companions

摘要

Mortality in patients with rheumatoid arthritis (RA) is higher compared to the general population, although the exact percentage of excess mortality attributable to RA depends on various factors [1,4]. Hospital-based studies tend to render higher mortality rates than community-based surveys, as well as studies focusing on older RA patients or patients with long-standing disease before study entry. In recent years, the focus in such analyses has mainly been on cardiovascular disease as the most common cause of death, both in the general and even more so in the RA population [1, 2]. Seropositive female RA patients have twice the expected cardiovascular mortality compared to the general population [3]. This may reflect an increased inflammatory disease burden promoting atherosclerosis. Another important cause of excess deaths in RA is infection, which seems to rise with disease duration [1]. Various renal complications adding to morbidity and mortality may also be seen in RA (table 1), many occurring simultaneously [2]. The precise contribution of renal disease to increased mortality is still vigorously debated, since former studies described no excess fatalities attributable to renal disease [4], or a death rate 20 times that of control populations [5]. It remains unclear if the excess mortality in RA patients with renal disease is based on the higher incidence of amyloidosis in this population alone, or if other renal disease entities confer an increased death rate as well.