Chronic Kidney Disease and Adverse Pregnancy Outcomes: A Systematic Review and Meta-analysis

Objective

Chronic kidney disease (CKD) has been linked with adverse pregnancy outcomes, but few studies have examined the influence of cause and severity. The aim of this meta-analysis was to synthesize the evidence on CKD and adverse pregnancy outcome, by cause and severity of CKD where reported.

Data sources

We searched PubMed, Embase, and Web of Science from inception to May 2021. Study selection and Data Extraction: Studies reporting associations between CKD and adverse pregnancy outcomes were included according to pre-defined eligibility criteria (PROSPERO protocol registration: CRD42020211925). Two reviewers independently screened titles, abstracts, and full-text articles and performed data extraction. The certainty of the evidence was assessed using the GRADE approach.

Main Outcomes and Measures: We used random-effects meta-analyses to calculate pooled estimates. Primary outcomes included pre-eclampsia, Caesarean section (CS), preterm birth (PTB <37 wk.) and small for gestational age (SGA).

Results

In total, 31 studies were included. The certainty of the evidence was deemed to be ‘very low' for all outcomes using the GRADE approach as expected given the observational study design. Pre-pregnancy CKD was associated with pre-eclampsia [pooled adjusted odds ratio (aOR)=2.58 (1.33-5.01)], CS [aOR=1.65 (1.21-2.25)], PTB [aOR=1.73 (1.31-2.27)] and SGA [aOR= 1.93 (1.06-3.52)]. Subgroup analyses suggested that different causes of CKD had differing risks for adverse pregnancy outcomes, and later stages of CKD, compared to earlier stages, were associated with higher odds of pre-eclampsia [crude OR = 2.77 (1.73-4.44)], PTB [4.21 (2.99-5.92)], and SGA [2.43 (1.33-4.46)].

Conclusions

CKD was associated with a higher risk of adverse pregnancy outcomes, and the degree of risk varied by cause and severity. These findings highlight the need for further studies of a more robust quality evaluating the effects of cause and severity of kidney disease on adverse pregnancy outcomes.

Key messages

Pre-pregnancy CKD was associated with higher risk of adverse pregnancy outcomes. The risk of adverse pregnancy outcomes varied by CKD cause and severity.

Association between preeclampsia and attention-deficit hyperactivity disorder: a population-based and sibling-matched cohort study

OBJECTIVE

To examine the association between preeclampsia and attention-deficit hyperactivity disorder (ADHD), using a large Swedish-based registry cohort.

METHODS

This study comprised 2 047 619 children, with 114 934 (5.6%) cases of ADHD. Preeclampsia was based on two alternate definitions: (i) preeclampsia (using ICD-9/ICD-10) and (ii) preeclampsia and small for gestational age (SGA) combined. ADHD was determined in one of two ways: (i) if a diagnosis of ADHD was present in the National Patient Register or (ii) if an individual was in receipt of ADHD medication in the Prescribed Drug Register. Multivariate Cox proportional hazards regression analysis allowed adjustment for several perinatal/sociodemographic factors. Sibling-matched analysis further controlled for shared genetic and familial confounding.

RESULTS

In the adjusted Cox model, preeclampsia was associated with an increase in likelihood of ADHD (HR: 1.15, 95% CI: 1.12, 1.19). The HR for preeclampsia and those born SGA was 1.43 (95% CI: 1.31, 1.55) in the adjusted model, compared to those unexposed to preeclampsia/SGA. The sibling-matched analysis did not materially change these associations (HR: 1.13, 95% CI: 1.05, 1.22) and 1.55 (95% CI: 1.28, 1.88).

CONCLUSIONS

Exposure to preeclampsia or preeclampsia/SGA was associated with ADHD, independent of genetic/familial factors shared by siblings. However, it is important to note that sibling-matched analysis can only adjust for factors that are constant between pregnancies; therefore, residual confounding cannot be ruled out. Further research is needed to explore modifiable risk factors and identify those most-at-risk babies following delivery.

Preeclampsia and the risk of chronic kidney disease: a national registry-based cohort study

Background

Preeclampsia is associated with increased risk of future cardiovascular disease, but evidence for associations with chronic kidney disease (CKD) has been inconsistent to date. We aimed to measure associations between preeclampsia and long-term CKD in a population-based sample of parous women, and to identify whether the risk differs by CKD subtype.

Methods

Using data from the Swedish Medical Birth Register, singleton live births from 1973-2012 were identified and linked to data from the Swedish Renal Register and National Patient Register (up to 2013). Preeclampsia was the main exposure of interest and was treated as a time-dependent variable. The primary outcome was maternal CKD, and this was classified into 5 subtypes: hypertensive, diabetic, glomerular/proteinuric, tubulo-interstitial, other/non-specific CKD. Cox proportional hazard regression models were used for analysis. Women with pre-pregnancy comorbidities were excluded.

Results

The dataset included 1,924,591 unique women who had 3,726,819 singleton pregnancies. The median follow-up was 20.7 (interquartile range 9.9-30.0) years. Overall, 90,964 women (4.7%) experienced preeclampsia and 18,146 (0.9%) developed CKD. Women who had preeclampsia had higher risk of developing any CKD during follow-up (aHR 1.88, 95% CI 1.79-1.98). The risk differed by CKD subtype, and was higher for hypertensive CKD (aHR 3.76, aHR 3.09-4.57), diabetic CKD (aHR 3.45, 95% CI 2.83-4.21) and glomerular/proteinuric CKD (aHR 2.08, 95% CI 1.90-2.29). Women who had preterm preeclampsia, recurrent preeclampsia, or preeclampsia complicated by pre-pregnancy obesity were also at greater risk of any CKD.

Conclusions

Women with a history of preeclampsia are at increased risk of long-term CKD. The risk is most marked for hypertensive CKD, diabetic CKD, and glomerular/proteinuric CKD. The absolute risk of CKD related to preeclampsia is substantial, and these women may warrant systematic renal monitoring in the years following delivery.

Key messages

Preeclampsia is an independent predictor of long-term risk of chronic kidney disease in otherwise healthy parous women. Women with a history of preeclampsia may warrant systematic renal monitoring through additional blood pressure, blood glucose, and proteinuria checks.

Adverse pregnancy outcomes and long-term risk of maternal renal disease: a systematic review

Background

Little is known about the long-term risk of renal disease following adverse pregnancy outcomes, such as hypertensive disorders of pregnancy (HDP), gestational diabetes (GDM) or preterm delivery. We aimed to investigate associations between adverse pregnancy outcomes and maternal chronic kidney disease (CKD) and end-stage kidney disease (ESKD), by synthesising results of relevant studies.

Methods

A systematic search of PubMed, EMBASE and Web of Science was done up to July 2018. Case-control and cohort studies were eligible for inclusion if they provided original effect estimates for associations between adverse pregnancy outcomes (HDP, GDM, preterm) and maternal renal disease (primary outcomes: CKD, ESKD; secondary outcomes: renal hospitalisation, renal mortality). Two independent reviewers extracted data and assessed risk of bias. Random effects meta-analyses were conducted to determine pooled adjusted odds ratio (AOR) and 95% confidence interval (95%CI) for each association.

Results

Of 5,120 studies retrieved, 21 studies met inclusion criteria (4,483,847 participants). HDP was associated with increased odds of ESKD (AOR 6.58, 95%CI 4.06-10.65), CKD (AOR 2.08, 95%CI 1.06-4.10), renal hospitalisation (AOR 2.29, 95%CI 1.42-3.71). The magnitude of association was dependent on HDP subtype: AOR for preeclampsia and ESKD was 4.87 (95%CI 3.01-7.87); gestational hypertension and ESKD was 3.65 (95%CI 2.34-5.67); other HDP (including chronic hypertension) and ESKD was 14.67 (95%CI 3.21-66.97). Preterm delivery was associated with increased odds of ESKD (AOR 2.16, 95%CI 1.64-2.85). GDM was associated with increased odds of CKD among black women (AOR 1.78, 95%CI 1.18-2.70), but not Caucasian women (AOR 0.81, 95%CI 0.58-1.13)

Conclusions

Women who experience adverse pregnancy outcomes have increased odds of renal disease, especially after HDP. Risk stratification and preventive interventions may be needed to reduce the risk of clinically significant renal disease in mothers.

Key messages

This is the first study to summarise the long-term risk of renal disease among women who experience a range of adverse pregnancy outcomes. Women who experience hypertensive disorders in pregnancy, preterm delivery, or gestational diabetes are at increased odds of renal disease.

Preterm delivery is associated with long-term risk of maternal renal disease

Background

Preterm delivery is an independent risk factor for maternal cardiovascular disease. Little is known about the association between preterm delivery and maternal renal function, and whether any association is independent of preeclampsia or intra-uterine growth restriction. This study aimed to examine the association between gestational age and long-term maternal chronic kidney disease (CKD) and end-stage kidney disease (ESKD).

Methods

Using data from the Swedish Medical Birth Register, singleton live births from 1973-2012 were identified and linked to data from the Swedish Renal Register and National Patient Register (up to 2013). Women with pre-pregnancy CKD/ESKD, cardiovascular disease, diabetes, hypertension, systemic lupus erythematosus were excluded. Gestational age at delivery was the main exposure, treated as a time-dependent variable. Primary outcomes were maternal CKD or ESKD. Cox regression was used, adjusting for maternal age, year of delivery, country of origin, education, parity, interpregnancy interval, smoking, BMI, gestational diabetes. Models were stratified by exposure to preeclampsia or small for gestational age (SGA).

Results

There were 3,847,694 pregnancies among 1,990,273 unique women. Nine percent of women (n = 172,915) had at least one preterm delivery (<37 weeks). Exposure to preterm delivery was associated with higher risk of CKD (aHR 1.48, 95%CI 1.41-1.54) and ESKD (aHR 2.52, 95%CI 2.17-2.92). Earlier gestational age at delivery was associated with increasing risk of CKD and ESKD. Women with spontaneous preterm delivery were at higher risk of CKD (vs. normal term, aHR 1.33, 95% CI 1.26-1.40) and ESKD (aHR 2.02, 95%CI 1.69-2.40) independently of preeclampsia/SGA. Associations persisted after excluding women who developed postpartum cardiovascular disease, hypertension or diabetes.

Conclusions

Women who gave birth at earlier gestation were at higher risk of later CKD and ESKD. This association persisted independently of preeclampsia and SGA.

Key messages

Preterm delivery is an independent predictor of long-term maternal renal disease. Obstetric history should be considered as part of overall risk stratification for chronic kidney disease in women.

Comparison of three commercially available placental growth factor-based tests in women with suspected preterm pre-eclampsia: the COMPARE study

OBJECTIVE

To compare the performance of three placental growth factor (PlGF)-based tests in predicting delivery within 14 days from testing in women with suspected preterm pre-eclampsia before 35 weeks' gestation.

METHODS

This was a retrospective analysis of samples collected from three prospective pregnancy cohort studies. Participants were pregnant women with suspected preterm pre-eclampsia recruited in tertiary maternity units in the UK and Ireland. Samples were analyzed simultaneously according to the manufacturers' directions. The tests compared were the DELFIA Xpress PlGF 1-2-3 test, the Triage PlGF test and the Elecsys immunoassay soluble fms-like tyrosine kinase-1 (sFlt-1)/PlGF ratio. Areas under receiver-operating characteristics curves (AUCs) were compared. The main outcome measure was detection of a difference of 0.05 in AUC between tests for delivery within 14 days of testing.

RESULTS

Plasma samples from 396 women and serum samples from 244 women were assayed. In predicting delivery within 14 days secondary to suspected pre-eclampsia prior to 35 weeks' gestation, no significant differences were observed in AUCs (P = 0.795), sensitivities (P = 0.249), positive predictive values (P = 0.765) or negative predictive values (P = 0.920) between the three tests. The specificity of the Elecsys sFlt-1/PlGF ratio test was higher than that of the other two tests (P < 0.001).

CONCLUSIONS

The tests perform similarly in their prediction of need for delivery within 14 days in women with suspected pre-eclampsia. The high negative predictive values support the role of PlGF-based tests as 'rule-out' tests for pre-eclampsia. © 2018 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Parental physical and lifestyle factors and their association with newborn body composition

OBJECTIVE

To investigate the parental physical and lifestyle determinants of newborn body composition.

DESIGN

Prospective cohort study.

SETTING

Cork University Maternity Hospital, a tertiary referral hospital in Cork, Ireland.

POPULATION

All babies were recruited as part of a prospective birth cohort, Babies After

SCOPE

Evaluating the Longitudinal Impact Using Neurological and Nutritional Endpoints (BASELINE). These babies were recruited from women who had participated in the Screening of Pregnancy Endpoints (SCOPE) study Ireland, a prospective, multicentre cohort study

METHODS

Multivariate linear regression was used to analyse the effect of a range of maternal and paternal physical and lifestyle features on neonatal body fat percentage (BF%).

MAIN OUTCOME MEASURES

Neonatal BF%. Neonatal adiposity was assessed within 48 hours of birth using air displacement plethysmography (PEAPOD(®) ).

RESULTS

In all, 1243 infants were enrolled in the study. Increasing maternal body mass index (adjusted mean difference 0.09; 0.04, 0.15) and waist height ratio (adjusted mean difference 6.59; 0.27, 12.92) were significantly associated with increased neonatal BF%. In contrast, maternal smoking was associated with reduced neonatal BF% compared with non smokers (adjusted mean difference -0.55; -1.07, -0.03). Infant sex significantly altered neonatal BF%, with female infants having higher neonatal BF% compared with male infants (adjusted mean difference 1.98; 1.54, 2.53). No association was observed between paternal body mass index (BMI), paternal age or paternal smoking and neonatal BF%.

CONCLUSIONS

Maternal smoking, BMI, waist height ratio and infant sex were associated with altered BF%.

TWEETABLE ABSTRACT

Maternal smoking, BMI, waist height ratio and infant sex are associated with altered neonatal body fat percentage.

Previous pregnancy loss has an adverse impact on distress and behaviour in subsequent pregnancy

OBJECTIVE

To investigate whether women with previous miscarriages or terminations have higher levels of anxiety, depression, stress, and altered behaviours in a subsequent pregnancy.

DESIGN

A retrospective analysis of 5575 women recruited into the Screening for Pregnancy Endpoints (SCOPE) study, a prospective cohort study.

SETTING

Auckland, New Zealand, Adelaide, Australia, Cork, Ireland, and Manchester, Leeds, and London, UK.

POPULATION

Healthy nulliparous women with singleton pregnancies.

METHODS

Outcomes were recorded at 15 and 20 weeks of gestation.

MAIN OUTCOME MEASURES

Short-form State-Trait Anxiety Inventory (STAI) score, Perceived Stress Scale score, Edinburgh Postnatal Depression Scale score, and pregnancy-related behaviour measured using behavioural responses to pregnancy score.

RESULTS

Of the 5465 women included in the final analysis, 559 (10%) had one and 94 (2%) had two previous miscarriages, and 415 (8%) had one and 66 (1%) had two previous terminations of pregnancy. Women with one previous miscarriage had increased anxiety (adjusted mean difference 1.85; 95% confidence interval, 95% CI 0.61-3.09), perceived stress (adjusted mean difference 0.76; 95% CI 0.48-1.03), depression (adjusted odds ratio, aOR 1.26; 95% CI 1.08-1.45), and limiting/resting behaviour in pregnancy (adjusted mean difference 0.80; 95% CI 0.62-0.97). In women with two miscarriages, depression was more common (aOR 1.65; 95% CI 1.01-2.70) and they had higher scores for limiting/resting behaviour in pregnancy (adjusted mean difference 1.70; 95% CI 0.90-2.53) at 15 weeks of gestation. Women with one previous termination displayed elevated perceived stress (adjusted mean difference 0.65; 95% CI 0.08-1.23) and depression (aOR 1.25; 95% 1.08-1.45) at 15 weeks of gestation. Women with two previous terminations displayed increased perceived stress (adjusted mean difference 1.43; 95% CI 0.00-2.87) and depression (aOR 1.67; 95% 1.28-2.18).

CONCLUSIONS

This study highlights the psychological implications of miscarriage and termination of pregnancy.

Coeliac disease and pregnancy outcomes

Coeliac disease is a gluten-sensitive enteropathy affecting up to 1% of the population. An accumulating body of evidence supports the association of coeliac disease with adverse pregnancy outcomes, including increased risk of miscarriage and intrauterine growth restriction. Reports differ regarding the extent and severity of these associations, in addition to the exact pathophysiology underlying these associations. Overall, coeliac disease is believed to be a significant condition in pregnancy and reproductive medicine with some advocating the screening of coeliac disease in all pregnant women or some specific high-risk groups.

The impact of maternal celiac disease on birthweight and preterm birth: a Danish population-based cohort study

BACKGROUND

Adverse pregnancy outcomes have been associated with maternal celiac disease (CD). In this study, we investigate the effect of treated and untreated maternal CD on infant birthweight and preterm birth.

METHODS

A population-based cohort study consisted of all singleton live births in Denmark between 1 January 1979 and 31 December 2004 was used. A total of 1,504,342 babies were born to 836,241 mothers during the study period. Of those, 1105 babies were born to women with diagnosed CD and 346 were born to women with undiagnosed CD. Women with diagnosed CD were considered as treated with a gluten free diet while women with undiagnosed CD were considered as untreated. The outcome measures were: birthweight, small for gestational age (SGA: birthweight <10th centile), very small for gestational age (VSGA: birthweight <5th centile) and preterm birth. We compared these measures in treated and untreated women with those of a reference group (no history of CD).

RESULTS

Women with untreated CD delivered smaller babies [difference = -98 g (95% CI: -130, -67)], with a higher risk of SGA infants [OR = 1.31 (95% CI: 1.06, 1.63)], VSGA infants [OR = 1.54 (95% CI: 1.17, 2.03)] and preterm birth [OR = 1.33 (95% CI: 1.02, 1.72)] compared with women without CD. Women with treated CD had no increased risk of reduced mean birthweight, risk of delivering SGA and VSGA infants or preterm birth compared with women without CD.

CONCLUSION

Untreated maternal CD increases the risk of reduced birthweight, the risk of delivering SGA and VSGA infants and preterm birth. Diagnosis and presumed treatment of maternal CD with a gluten-free diet appeared to result in a birthweight and preterm birth rate similar to those in women without CD.