Background The mortality rate in rheumatoid arthritis (RA) is higher than in the general population. Several published data exist on the prevalence of the most important complications: systemic vasculitis (SV), generalised secondary AA amyloidosis (AAa), generalised septic infection (GSI), but only a few studies discuss the causal, or additive role of these complications in the mortality of RA.

Objectives The aim of this study was to determine: (1) the proportion of basic and accompanying diseases at autopsy of RA patients, (2) the incidence of major complications, e.g. SV, AAa, and GSI, (3) the mortality due to SV, AAa, or GSI, and (4) the clinically missed major complications in RA.

Patient Population.

A randomised autopsy population of 161 in-patients (female 116, average age of 64.9 years; male 45, average age of 66.2 years at death) with RA was studied; these patients died at the National Institute of Rheumatology between 1970 and 1992.

The basic disease, complication (s), and causes of death were determined on the basis of the autopsy findings and confirmed by a detailed review of extensive histological material (50–100 tissue blocks from each patient). The tissue samples were fixed in 8% aqueous formalin at pH 7.6 and embedded in paraffin. Serial sections were cut and stained with haematoxylin-eosin, light green-orcein, sirius red F3BA, Ziehl-Neelsen?s method, PAS reaction, and Congo red according to Romhányi, without alcoholic differentiation, and covered by gum-arabic (1). The (AA) amyloid was determined and characterised histochemically, and by immunohistochemical reactions.

Results

1. RA was the underlying cause of death in 117 cases (73%), while in the remaining 44 (27%) cases some other basic disease – such as atherosclerosis in 30 (19%) (atherosclerosis was more or less pronounced in about 66% of the cases), tumours in 8 (5%) of 18, tuberculosis in 2 (1.3%) of 13, accidental (postoperative thromboembolism, hypertensive crisis) in 2 (1.3%), acute and subacute hepatic necrosis, respectively, in 2 (1.3%) cases.

2. SV was found in 36 (22.4%), AAa in 34 (21.1%), GSI in 22 (13.7%) of 161 RA patients. In 78 cases (48.4%) RA was not complicated by SV, AAa, GSI, in 83 cases (51.6%) one or more of these complications was present. In 74 patients (46%) only one complication, and in 9 (5.6%) two of the above mentioned complications existed simultaneously.

3. SV led to death in 19 (11.8%) of 36, AAa in 17 (10.6%) of 34, GSI in 22 (13.7%) of 22 cases.

4. SV was detected clinically in 7 of 36 patients (19.4 rel%), AAa in 9 of 34 (26.5 rel%), GSI in 10 of 22 (45.4 rel%). Of a total of 92 complications in 83 patients only 26 (28.3%) were recognised clinically.

Conclusion Major complications, e.g. SV, AAa, GSI were the main causes of death in our RA patients. They were responsible for 58 (49.6 rel%) in 117 cases (36% of 161 RA patients). Other RA related complications were responsible altogether for 59 (50.4%) of 117 cases (36.6% of 161 RA patients). The cause of death was not related directly to RA in 44 (27.3%) of 161 RA patients.

Coexisting complications modify the basic disease of RA and their own clinical manifestation, which may lead to an incorrect diagnosis or late recognition of the complications. More than half of de facto lethal complications was not diagnosed clinically.