Women who develop pre-eclampsia during pregnancy are at increased risk of developing kidney disease later in life, reports a study in the British Medical Journal.
Using national registry data, the researchers identified all women in Denmark who had at least one pregnancy lasting at least 20 weeks between 1978 and 2015. Hazard ratios for later diagnosis of kidney disease were compared for women with and without a history of pre-eclampsia, stratified by gestational age at delivery. The analysis included more than 1 million women, average follow-up of 18.6 years.
Kidney disease was diagnosed in 14,816 women, 7.2% of whom had a history of pre-eclampsia. Pre-eclampsia was associated with an increased risk of chronic renal conditions, with hazard ratios (HRs) of 3.93 for early preterm pre-eclampsia (34 weeks), 5.33 for late preterm pre-eclampsia (34 to 36 weeks), and 2.27 for term pre-eclampsia (37 weeks or after). Associations were strongest for the diagnoses of chronic kidney disease, hypertensive kidney disease, and glomerular/proteinuric kidney disease. The associations were only somewhat weakened by adjustment for cardiovascular disease and hypertension.
The greatest pre-eclampsia-related increases in kidney disease risk were seen within 5 years of the last pregnancy: HR 6.11 for chronic kidney disease and 4.77 for glomerular/proteinuric disease. Though still significant, the associations were weaker at 5 years or longer after the last pregnancy: HR 2.06 and 1.50, respectively. History of pre-eclampsia was not strongly related to acute renal conditions.
Although pre-eclampsia has been linked to end-stage renal disease, there are conflicting data on its association with chronic kidney disease and kidney dysfunction. In this nationwide cohort study, history of pre-eclampsia is strongly associated with increased risks of chronic but not acute kidney diseases. The association is strongest for chronic kidney disease and glomerular/proteinuric disease, particularly within 5 years of the latest pregnancy [Kristensen JH, et al. Pre-eclampsia and risk of later kidney disease: nationwide cohort study BMJ 2019; 365: 1516.]