Pregnancy and progression of IgA nephropathy: results of an Italian multicenter study.
BACKGROUND
Whether pregnancy impacts on the long-term outcome of immunoglobulin A (IgA) nephropathy is unknown. This study aims to compare the long-term outcome of kidney disease in women with IgA nephropathy and preserved kidney function who did and did not become pregnant.


METHODS
Multicenter longitudinal cohort study.


METHODS
Women of childbearing age with biopsy-proven IgA nephropathy, serum creatinine level<or=1.2 mg/dL at diagnosis, and minimum follow-up of 5 years after biopsy recruited from 35 nephrology centers participating in a national collaborative study group of pregnancy and kidney disease sponsored by the Italian Society of Nephrology.


METHODS
Pregnancy, treated as a time-dependent variable; baseline proteinuria; hypertension; and kidney biopsy histologic characteristics.


METHODS
Rate of change in estimated creatinine clearance, change in proteinuria, and new-onset hypertension.


RESULTS
245 patients were enrolled. Of these, 223 women (136 and 87 in the pregnancy and nonpregnancy groups, respectively) had serum creatinine levels<or=1.2 mg/dL at diagnosis. Baseline data (including age, estimated creatinine clearance, prevalence of hypertension, and histologic grade of kidney damage) were similar between groups with the exception of proteinuria (protein excretion, 1.33 vs 0.95 g/d in the pregnancy vs nonpregnancy groups, respectively; P=0.03). Kidney function decreased 1.31 mL/min/y (95% CI, 0.99-1.63) during a median follow-up of 10 years (range, 5-31 years) and did not differ between groups. Baseline proteinuria predicted a faster decrease, but did not modify the effect of pregnancy. Pregnancy did not affect changes in proteinuria over time or risk of new-onset hypertension.


CONCLUSIONS
Unrecognized or unmeasured factors associated with the decision of becoming pregnant might have influenced results.


CONCLUSIONS
Pregnancy does not seem to affect the long-term outcome of kidney disease in women with IgA nephropathy and preserved kidney function.
Limardo
Monica
M
Department of Nephrology, Dialysis and Transplantation, A. Manzoni Hospital, Lecco, Italy.
Imbasciati
Enrico
E
Ravani
Pietro
P
Surian
Maurizio
M
Torres
Diletta
D
Gregorini
Gina
G
Magistroni
Riccardo
R
Casellato
Daniela
D
Gammaro
Linda
L
Pozzi
Claudio
C
D000328:Adult; D018450:Disease Progression; D005260:Female; D005922:Glomerulonephritis, IGA / Q000503:physiopathology; D006801:Humans; D007558:Italy; D007668:Kidney / Q000503:physiopathology; D008137:Longitudinal Studies; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology; D011446:Prospective Studies