Ambulatory blood pressure monitoring in children: A retrospective single-center study

OBJECTIVES

(1) Compare 24-hour ambulatory blood pressure monitoring (ABPM) diagnoses in a pediatric population with the new 2022 guidelines to the original diagnoses with the 2014 guidelines. (2) Determine whether findings of hypertension from ABPM could be predicted from prior patient data. (3) Determine whether ABPM readings could predict left ventricular mass index (LVMI) in patients who obtained an echocardiogram (ECHO).

STUDY DESIGN

Single-center retrospective study on patients referred to Pediatric Nephrology Clinic for evaluation of elevated blood pressure who underwent ABPM from 2015 to 2018. Predictions of hypertension were obtained using a logistic regression model, and predictions of LVMI were performed using regression models including (a) the wake systolic and diastolic BP indices, or (b) additionally including the standard deviation (SD) of wake SBP and DBP.

RESULTS

With the change in 2022 to new ABPM guidelines from the AHA, comparing the old and new guidelines led to 70% of previous pre-hypertensive diagnoses now meeting criteria for diagnosis of hypertension, and a rise from 21% of the ABPMs meeting criteria for hypertension to 51% now meeting criteria. In a logistic regression model, prior patient data were not predictive of a diagnosis of hypertension from ABPM (Nagelkerke's R ² = 0.04). Among the individual variables studied, none were statistically significant. For prediction of LVMI, the SD of wake SBP and DBP were significantly associated with increased LVMI, but the wake SBP and DBP indices were not.

CONCLUSIONS

In our patient population, the new ABPM guidelines led to a significant increase in diagnoses of hypertension. Prior patient data was not sufficient to predict a diagnosis of hypertension by ABPM, supporting the need for evaluation by ABPM as the gold standard. Our analysis of the relationship between ABPM readings and LVMI supports the hypothesis that BP variability contributes to increased LVMI. These data are consistent with growing evidence in the adult literature that BP variability detected by ABPM is associated with left-ventricular hypertrophy.

Mid-aortic syndrome is associated with increased left ventricular mass index in Takayasu arteritis

Background

Mid-aortic syndrome (MAS) may induce changes in cardiac structure among patients with Takayasu arteritis (TA).

Methods

Consecutive adult patients with TA (January 1, 2011 to January 1, 2018) were enrolled and their data was retrospectively analyzed.

Results

Patients were divided into MAS group (100/457 patients, 21.8%) and non-MAS group (357, 78.1%). The left ventricular mass index (LVMI) was higher in the MAS group than the non-MAS (113.78±26.82 versus 100.74±23.66 g/m², respectively; P<0.001). The MAS group showed higher prevalence than the non-MAS group of mild-to-severe mitral regurgitation (9.0% and 3.9%, respectively; P=0.040) and aortic regurgitation (26% and 14.8%, respectively; P=0.003). No difference was found in the rates of heart failure (27.0% and 19.9% for MAS and non-MAS, respectively; P=0.126). The MAS group also showed lower estimated glomerular filtration rates than the non-MAS group (89.93±18.89 versus 96.16±21.60 mL/min/1.73 m², respectively; P=0.009) and higher prevalence of renal artery stenosis (57% versus 43.7%; P=0.018). MAS was independently related to greater LVMI in both unadjusted model [β=12.60; 95% confidence interval (CI): 7.09–18.11; P<0.001] and the model adjusted for multiple indices (β=9.91; 95% CI: 4.57–15.25; P<0.001) in multivariate linear analysis. The LVMI significantly decreased from 111.49±25.65 to 100.36±22.91 g/m² (P<0.001) among 55 patients who underwent successful revascularization treatment for MAS, while no significant difference (P=0.635) was observed among patients treated with medicine alone.

Conclusions

TA-induced MAS is a potential independent risk factor for increased LVMI, and revascularization therapy for MAS is effective in reversing structural changes in the heart.

Adiposity, Sex, and Cardiovascular Disease Risk in Children With CKD: A Longitudinal Study of Youth Enrolled in the Chronic Kidney Disease in Children (CKiD) Study

RATIONALE & OBJECTIVE

Traditional and nontraditional cardiovascular disease risk factors are highly prevalent in children with chronic kidney disease (CKD). We examined the longitudinal association of adiposity with cardiac damage among children with CKD and explored whether this association was modified by sex.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Children with mild-to-moderate CKD enrolled in the Chronic Kidney Disease in Children (CKiD) Study at 49 pediatric nephrology centers across North America.

EXPOSURE

Age- and sex-specific body mass index (BMI) z score.

OUTCOME

Age- and sex-specific left ventricular mass index (LVMI) z score and left ventricular hypertrophy (LVH).

ANALYTICAL APPROACH

Longitudinal analyses using mixed-effects models to estimate sex-specific associations of BMI z scores with LVMI z score and with LVH, accounting for repeated measurements over time.

RESULTS

Among 725 children with 2,829 person-years of follow-up, median age was 11.0 years and median estimated glomerular filtration rate was 52.6mL/min/1.73m2. Nearly one-third of both boys and girls were overweight or obese, median LVMI z score was 0.18 (IQR: -0.67, 1.08), and 11% had LVH. Greater BMI z scores were independently associated with greater LVMI z scores and greater odds of LVH. For each 1-unit higher BMI z score, LVMI z score was 0.24 (95% CI, 0.17-0.31) higher in boys and 0.38 (95% CI, 0.29-0.47) higher in girls (Pinteraction = 0.01). For each 1-unit higher BMI z score, the odds of LVH was 1.5-fold (95% CI, 1.1-2.1) higher in boys and 3.1-fold (95% CI, 1.8-4.4) higher in girls (Pinteraction = 0.005).

LIMITATIONS

Not all children had repeated measurements. LVH is a surrogate and not a hard cardiac outcome. The observational design limits causal inference.

CONCLUSIONS

In children, adiposity is independently associated with the markers of cardiac damage, LVMI z score and LVH. This association is stronger among girls than boys. Pediatric overweight and obesity may therefore have a substantial impact on cardiovascular risk among children with CKD.

Evolution of Echocardiographic Measures of Cardiac Disease From CKD to ESRD and Risk of All-Cause Mortality: Findings From the CRIC Study

RATIONALE & OBJECTIVE

Abnormal cardiac structure and function are common in chronic kidney disease (CKD) and end-stage renal disease (ESRD) and linked with mortality and heart failure. We examined changes in echocardiographic measures during the transition from CKD to ESRD and their associations with post-ESRD mortality.

STUDY DESIGN

Prospective study.

SETTING & PARTICIPANTS

We studied 417 participants with CKD in the Chronic Renal Insufficiency Cohort (CRIC) who had research echocardiograms during CKD and ESRD.

PREDICTOR

We measured change in left ventricular mass index, left ventricular ejection fraction (LVEF), diastolic relaxation (normal, mildly abnormal, and moderately/severely abnormal), left ventricular end-systolic (LVESV), end-diastolic (LVEDV) volume, and left atrial volume from CKD to ESRD.

OUTCOMES

All-cause mortality after dialysis therapy initiation.

ANALYTICAL APPROACH

Cox proportional hazard models were used to test the association of change in each echocardiographic measure with postdialysis mortality.

RESULTS

Over a mean of 2.9 years between pre- and postdialysis echocardiograms, there was worsening of mean LVEF (52.5% to 48.6%; P<0.001) and LVESV (18.6 to 20.2mL/m^2.7; P<0.001). During this time, there was improvement in left ventricular mass index (60.4 to 58.4g/m^2.7; P=0.005) and diastolic relaxation (11.11% to 4.94% with moderately/severely abnormal; P=0.02). Changes in left atrial volume (4.09 to 4.15mL/m²; P=0.08) or LVEDV (38.6 to 38.4mL/m^2.7; P=0.8) were not significant. Worsening from CKD to ESRD of LVEF (adjusted HR for every 1% decline in LVEF, 1.03; 95% CI, 1.00-1.06) and LVESV (adjusted HR for every 1mL/m^2.7 increase, 1.04; 95% CI, 1.02-1.07) were independently associated with greater risk for postdialysis mortality.

LIMITATIONS

Some missing or technically inadequate echocardiograms.

CONCLUSIONS

In a longitudinal study of patients with CKD who subsequently initiated dialysis therapy, LVEF and LVESV worsened and were significantly associated with greater risk for postdialysis mortality. There may be opportunities for intervention during this transition period to improve outcomes.

Estimated GFR and Subsequent Higher Left Ventricular Mass in Young and Middle-Aged Adults With Normal Kidney Function: The Coronary Artery Risk Development in Young Adults (CARDIA) Study

BACKGROUND

Left ventricular hypertrophy is common and is associated with cardiovascular events and death among patients with known chronic kidney disease. However, the link between reduced glomerular filtration rate (GFR) and left ventricular mass index (LVMI) remains poorly explored among young and middle-aged adults with preserved kidney function. In this study, we examined the association of cystatin C-based estimated GFR (eGFRcys) and rapid decline in eGFR with subsequent LVMI.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

We included 2,410 participants from the Coronary Artery Risk Development in Young Adults (CARDIA) cohort with eGFRcys > 60mL/min/1.73m(2) at year 15 and who had an echocardiogram obtained at year 25.

PREDICTOR

eGFRcys at year 15 and rapid decline in eGFRcys (defined as >3% per year over 5 years from years 15 to 20).

OUTCOME

LVMI measured at year 25.

MEASUREMENTS

We adjusted for age, sex, race, diabetes, body mass index, low- and high-density lipoprotein cholesterol levels, cumulative systolic blood pressure, and albuminuria.

RESULTS

Mean age was 40±4 (SD) years, 58% were women, and 43% were black. After 10 years of follow-up, mean LVMI was 39.6±13.4g/m(2.7). Compared with eGFRcys > 90mL/min/1.73m(2) (n = 2,228), eGFRcys of 60 to 75mL/min/1.73m(2) (n = 29) was associated with 5.63 (95% CI, 0.90-10.36) g/m(2.7) greater LVMI (P = 0.02), but there was no association of eGFRcys of 76 to 90mL/min/1.73m(2) (n = 153) with LVMI after adjustment for confounders. Rapid decline in eGFRcys was associated with higher LVMI compared with participants without a rapid eGFRcys decline (β coefficient, 1.48; 95% CI, 0.11-2.83; P = 0.03) after adjustment for confounders.

LIMITATIONS

There were a limited number of participants with eGFRcys of 60 to 90mL/min/1.73m(2).

CONCLUSIONS

Among young and middle-aged adults with preserved kidney function, eGFRcys of 60 to 75mL/min/1.73m(2) and rapid decline in eGFRcys were significantly associated with subsequently higher LVMI. Further studies are needed to understand the mechanisms that contribute to elevated LVMI in this range of eGFRcys.

Levocarnitine Improves Cardiac Function in Hemodialysis Patients With Left Ventricular Hypertrophy: A Randomized Controlled Trial

BACKGROUND

Levocarnitine deficiency in hemodialysis patients is common. Although the effect of levocarnitine therapy on uremic anemia has been studied in small trials, its effects on cardiac function remain unclear.

STUDY DESIGN

Multicenter, prospective, open-label, parallel, randomized, controlled trial.

SETTING & PARTICIPANTS

Patients undergoing maintenance hemodialysis with carnitine deficiency (free carnitine plasma concentration < 40μmol/L) enrolled in 3 hemodialysis centers.

INTERVENTION

Random assignment to treatment for 12 months with oral levocarnitine therapy at a dose of 20mg/kg/d or control group (no levocarnitine therapy).

OUTCOMES & MEASUREMENTS

Cardiac function was assessed by echocardiography. The primary end point was change in ejection fraction from baseline at the end of the study. Secondary end points included changes in left ventricular mass index and clinical parameters from baseline at the end of the study.

RESULTS

222 patients were randomly assigned, of whom 148 patients (levocarnitine group, n=75; control group, n=73) were analyzed. Ejection fraction increased from baseline to the end of the study in the levocarnitine group by 5.43% (95% CI, 4.53%-6.32%), but not in the control group (change, -0.14%; between-group difference, 5.57% [95% CI, 4.48%-6.66%]; P<0.001). Left ventricular mass index decreased from baseline to the end of the study in the levocarnitine group (change of -8.89 [95% CI, -11.7 to -6.09] g/m(2)), but not in the control group (change of 1.62g/m(2); between-group difference, 10.50 [95% CI, 7.51 to 13.60] g/m(2); P<0.001). Levocarnitine therapy reduced N-terminal pro-brain natriuretic peptide (NT-proBNP) levels and improved the erythropoietin responsiveness index, whereas no such effects were observed in the control group.

LIMITATIONS

Not a double-blinded study.

CONCLUSIONS

Levocarnitine therapy is useful for hemodialysis patients with carnitine deficiency; these patients may benefit from such therapy, with amelioration of cardiac function and reduction of left ventricular mass index.