Prognosis of clinical renal disease and incidence of new renal findings in patients with rheumatoid arthritis: follow-up of a population-based study.

The objective of this study was to assess the long-term prognosis of nephropathy findings and the incidence of new abnormal clinical renal findings in patients with rheumatoid arthritis (RA). The original population-based cross-sectional study of 604 RA patients was carried out in 1988, 103 nephropathy patients being found. Controls matched for age, sex, and duration of RA were selected from among RA patients with normal renal function and urinalysis in 1988. In 2003, a follow-up study was made of the 103 nephropathy patients and 102 controls, and the median follow-up time was 13 years. In the original nephropathy group, serum creatinine exceeded 200 mumol/l in 8% of the original isolated hematuria patients, in 30% of the isolated proteinuria patients, in 57% of the combined hematuria and proteinuria patients, but in none of the isolated chronic renal failure (CRF) patients (p = 0.001 for the difference). Probable or definitive renal amyloidosis was diagnosed in 19% of the nephropathy patients. Dialysis therapy was given to 10 out of the 103 nephropathy patients, nine of them belonging to the original isolated proteinuria or combined hematuria and proteinuria groups. There were six renal deaths among the nephropathy patients, and none in the controls. In the control group, new abnormal renal findings, in most cases mild, were detected in 28%. Serum creatinine exceeded 200 mumol/l in 4% of the controls, and dialysis therapy was given to 2% of the controls. Probable or definitive renal amyloidosis was diagnosed in 4% of this group. With regards to the development or progression of chronic renal failure, the long-term clinical prognosis of isolated hematuria and isolated CRF was found to be favorable. Proteinuria alone or combined with hematuria or CRF was related to evidently poorer prognosis.

Death rates and causes of death in patients with rheumatoid arthritis: a population-based study.

OBJECTIVE: To assess the mortality and causes of death in a cross-sectional population-based study of 1042 patients with rheumatoid arthritis (RA). METHODS: In 1988, 604 RA patients [470 females (F), 134 males (M)] and 457 age- and sex-matched controls (352 F, 105 M) were examined prospectively (participants) and 438 (183 F, 81 M) non-participant RA patients retrospectively. In 1999, vital status and causes of death were determined. Mortality in the total RA population was compared to that in the general population, and that among participant RA patients to their matched controls. RESULTS: A total of 384 (37%) RA patients and 71 (16%) controls died. RA patients had increased mortality compared to the general population (standardized mortality ratios SMR 2.64) or controls (1.71). This was observed in both sexes. Over 40% of deaths in all groups were due to cardiovascular diseases. RA patients were at increased risk of dying of urogenital, gastrointestinal, respiratory and cardiovascular diseases, infections, and cancers when compared to the general population or controls. CONCLUSIONS: Our results show that a cross-sectional cohort of RA patients had an increased risk of death from various causes.

Renal disease as a predictor of increased mortality among patients with rheumatoid arthritis.

AIMS AND METHODS: Mortality among RA patients and controls was analyzed with special attention to renal disease in population-based material (originally screened in 1988) of 604 patients with RA (470 females, 134 males) and 457 age- and sex-matched controls (352 females, 105 males). In the original RA population, isolated hematuria (HU) was observed in 54, isolated proteinuria (PU) in 27, combined hematuria and proteinuria (HUPU) in 7, chronic renal failure (CRFtot) in 36 and isolated chronic renal failure without HU or PU (CRFisol) in 15 patients. Among the controls, HU was observed in 39, PU in 11, CRFtot in 32 and CRFisol in 16 subjects. HUPU was not observed in any of the controls. Microalbuminuria (20-200 microg/min) was observed in 34 RA patients and in 27 controls. Histologically confirmed amyloidosis was found in 13 RA patients and mesangial glomerulonephritis (MesGN) in 17 patients. The mortality was evaluated in 1999 from data of the Statistical Office of Finland. Statistical analysis was performed by Cox regression analysis. RESULTS: Mortality was significantly increased in the RA population as compared to controls: hazard ratio (HR) 1.78 (95% CI 1.34-2.31) for all RA patients; HR 2.12 (1.52-2.94) for females; HR 1.15 (0.75-1.77) for males. In the RA material, increased mortality was detected in patients with HUPU (HR 4.45; 1.54-12.84), PU (HR 3.54; 1.88-6.65), CRFtot (HR 3.74; 2.55-5.56) or microalbuminuria (HR 2.77; 1.64-4.69) when compared to those with normal clinical renal findings, whereas HU (HR 1.49; 0.88-2.52), CRFisol (HR 1.71; 0.82-3.54), bacteriuria (HR 0.96; 0.35-2.59) or pyuria (HR 0.65; 0.09-4.65) did not predict mortality. Renal amyloidosis was associated with an over twofold mortality rate (HR 2.31; 1.03-5.15), whereas mortality was within expected limits in RA patients with MesGN (HR 1.61; 0.49-5.24). CONCLUSION: Our results show that nephropathy presenting with combined hematuria and proteinuria, proteinuria, microalbuminuria or histologically confirmed amyloidosis is associated with increased mortality in RA patients, whereas mortality is within expected limits in those with isolated hematuria or mesangial glomerulonephritis.