We evaluated cardiovascular risk factors, morbidity and mortality in patients with lupus nephritis (LN). We prospectively studied 70 consecutive patients with LN, and 70 age- and sex-matched controls with systemic lupus erythematosus (SLE) but no evidence of nephropathy, from 1988 to 1998. Patients were evaluated at entry for hypertension, diabetes, hyperlipidaemia, smoking, menopause and antiphospholipid syndrome. The LN patients (64 women, 6 men) had a mean age of 35 years (SE 1.7, range 11-67). During the 10 years, 15 (21%) LN patients and 18 (25%) of the controls were lost to follow-up. Compared with controls, LN patients had a higher prevalence of hyperlipidaemia (44% vs. 2%, p<0.001), hypertension (44% vs. 9%, p<0.001) and antiphospholipid antibodies (45% vs. 22%, p=0.01) at study onset. At the last visit, 37 (67%) LN patients had normal plasma creatinine, 13 (24%) had renal failure and only five (9%) end-stage renal failure. Hyperlipidaemia (78% vs. 27%, p<0.001) and hypertension (67% vs. 32%, p=0.01) at study onset were associated with development of renal failure. Nine LN patients and one control died (16% vs. 2%, p=0.02). These patients showed more antiphospholipid syndrome (56% vs. 17%, p=0.03) and hyperlipidaemia (78% vs. 37%, p=0.03) at study onset. The main causes of death in LN patients were vascular complications (cardiovascular or cerebrovascular events) in five patients (four of whom had antiphospholipid antibodies) and sepsis in three.