No abstract

Prevalence of AA amyloid in rheumatoid arthritis (RA) is still unclear. The objective of this retrospective study was whether dedicated re-examination of autopsy tissues from RA patients increases the detection rate of amyloid compared to routine examination. Amyloid was re-examined in tissue samples and detection rate compared with original reports of 369 consecutively autopsied RA patients and 370 non-RA patients matched for sex, age, and year of autopsy between 1952 and 1991. Re-examination of 90% of the 739 cases showed doubling of the prevalence of amyloid compared with the original reports: from 18 to 30% in RA and from 2 to 4% in non-RA patients. In RA patients, cardiac amyloid was as frequent as renal amyloid. In RA patients with amyloid at re-examination, amyloidosis had been diagnosed before autopsy in 37%, and these patients had more inflammation and longer disease duration than RA patients without amyloid. Only 56% of RA patients with renal amyloid were known to have proteinuria. In conclusion, this autopsy study shows that amyloid in RA is a common finding which remains frequently undetected. In patients with active and long-lasting RA, a systematic search for amyloid may enable early diagnosis of amyloidosis, which will require effective suppression of inflammation.

RA patients seem to have an increased risk for myocardial damage. The influence of inflammation on the myocardium in RA needs further studies.

Infections, especially respiratory and urinary tract infections, are frequent causes of death in RA patients. The high proportion of undiscovered infections as a cause of death highlights the diagnostic difficulty. With a decreasing number of autopsies being performed at present, greater numbers of infections may be under-reported.

We studied causes of death (CoDs) between 1952 and 1991 assessed by a clinician before autopsy and then determined at autopsy by a pathologist in 369 subjects with rheumatoid arthritis (RA) and 370 subjects without RA (non-RA). We analysed clinical data for RA subjects between 1973 and 1991. In RA subjects, leading autopsy-based CoDs were RA, cardiovascular diseases and infections. Between diagnoses of CoDs by the clinician and those determined by the pathologist, RA subjects had lower agreement than did the non-RA regarding coronary deaths (Kappa reliability measure: 0.33 vs. 0.46). In non-RA subjects, autopsy-based coronary deaths showed a decline since the 1970s with no such decline in RA. Between subjects treated at any time during RA with disease-modifying anti-rheumatic drugs and those without, autopsy-based CoDs were similar. Coronary death being less accurately diagnosed in RA subjects may indicate that coronary heart disease in RA patients often remains unrecognized.