Hypertriglyceridaemia and hyperuricaemia are risk factors for progression of IgA nephropathy

Background. The prognosis of IgA nephropathy (IgAN) is variable and about 1 0-20% of patients pl-ogress to end-stage renal disease(ESRD) in 10 years. H ypertension, proteinuria and renal insufficiency at the time of diagnosis a re risk factors associated with poor prognosis. Lipid-abnormalities may hav e a role in the progression of glomerulonephritides, and glomerulosclerosis and atherosclerosis may have similar pathophysiological mechanisms. We the refore evaluated factors associated with cardiovascular diseases, especiall y hypercholesterolaemia, hypertriglyceridaemia, and hyperuricaemia, as pred ictors of the progression of IgAN. Methods. A total of 223 patients with IgAN (141 men, 82 women; median age 4 1 years, range 8-78 years) were studied. The following parameters were reco rded at the time of renal biopsy: presence of hypertension or diabetes, smo king habits, body mass index (BMI), serum creatinine, total and HDL-cholest erol, triglycerides, and urate and 24-h urinary protein excretion. The pati ents were followed up for 0.2-17 years (median 10 years) with respect to pr ogression of renal disease defined as elevation of serum creatinine above 1 25 mu mol/l in men or 105 mu mol/l in women, and over 20% elevation from ba seline. Results. Forty-one patients (18%) showed progression. Hypertriglyceridaemia and hyperuricaemia were significantly more common at the time of renal bio psy in patients with progressive than in those with stable disease. In pati ents with normal renal function at the time of diagnosis initial hypertrigl yceridaemia, hyperuricaemia, hypertension and proteinuria were independent risk factors for progression of IgAN in the Cox regression hazard model. Conclusions. Our results show that hypertriglyceridaemia and hyperuricaemia at the time of diagnosis are important, previously underestimated predicto rs of poor outcome in IgAN, although causality between these factors and pr ogression cannot be inferred from the present study.