A-K Wikström1, J Wikström, A Larsson, M Olovsson. 1. Department of Women's and Children's Health, University Hospital, Uppsala, Sweden. anna-karin.wikstrom@kbh.uu.se
Abstract
OBJECTIVE: 1) To assess the correlation between urine albumin/creatinine ratio (ACR) and 24-hour urine albumin excretion in women with pre-eclampsia, 2) to study the influence of potential confounders on this correlation and 3) to assess the variability of ACR between voids during a 24-hour period. DESIGN: Prospective study. SETTING: Fetal maternity ward, university hospital. POPULATION: Women with pre-eclampsia scheduled for quantitative albumin measurement with a 24-hour urine collection. METHODS: Random urine samples were obtained for analysis of ACRs during the time of 24-hour urine collections in 31 women. ACRs were also measured from the complete 24-hour collections. In five additional women, serial urine samples were obtained during the 24-hour collection. MAIN OUTCOME MEASURES: Correlation between ACRs and albumin amount in 24-hour urine samples. Variability of the ACRs during a 24-hour collection. RESULTS: The random ACR was poorly correlated to 24-hour excretion of urine albumin (R(2)= 0.42). Adjustment for maternal age and nifedipine medication significantly (P= 0.044 and P= 0.023, respectively) improved the correlation (R(2)= 0.60). The mean variability (highest/lowest) of ACR during a 24-hour period was 222%. The ACR from the 24-hour collection had an excellent correlation to 24-hour excretion of urine albumin (R(2)= 0.96). CONCLUSIONS: In women with pre-eclampsia, random ACR is not stable during the day and cannot predict 24-hour urine protein excretion accurately. ACR from the 24-hour collection is an accurate predictor of total albumin amount and can be used to minimise errors from incomplete collections.
OBJECTIVE: 1) To assess the correlation between urine albumin/creatinine ratio (ACR) and 24-hour urine albumin excretion in women with pre-eclampsia, 2) to study the influence of potential confounders on this correlation and 3) to assess the variability of ACR between voids during a 24-hour period. DESIGN: Prospective study. SETTING: Fetal maternity ward, university hospital. POPULATION: Women with pre-eclampsia scheduled for quantitative albumin measurement with a 24-hour urine collection. METHODS: Random urine samples were obtained for analysis of ACRs during the time of 24-hour urine collections in 31 women. ACRs were also measured from the complete 24-hour collections. In five additional women, serial urine samples were obtained during the 24-hour collection. MAIN OUTCOME MEASURES: Correlation between ACRs and albumin amount in 24-hour urine samples. Variability of the ACRs during a 24-hour collection. RESULTS: The random ACR was poorly correlated to 24-hour excretion of urine albumin (R(2)= 0.42). Adjustment for maternal age and nifedipine medication significantly (P= 0.044 and P= 0.023, respectively) improved the correlation (R(2)= 0.60). The mean variability (highest/lowest) of ACR during a 24-hour period was 222%. The ACR from the 24-hour collection had an excellent correlation to 24-hour excretion of urine albumin (R(2)= 0.96). CONCLUSIONS: In women with pre-eclampsia, random ACR is not stable during the day and cannot predict 24-hour urine protein excretion accurately. ACR from the 24-hour collection is an accurate predictor of total albumin amount and can be used to minimise errors from incomplete collections.
Authors: Sakineh Moaid Mohseni; Nafiseh Moez; Mohammad Mehdi Naghizadeh; Maryam Abbasi; Zohreh Khodashenas Journal: J Family Reprod Health Date: 2013-06