Apolipoprotein L1 gene variants associate with prevalent kidney but not prevalent cardiovascular disease in the Systolic Blood Pressure Intervention Trial.

Apolipoprotein L1 gene (APOL1) G1 and G2 coding variants are strongly associated with chronic kidney disease (CKD) in African Americans (AAs). Here APOL1 association was tested with baseline estimated glomerular filtration rate (eGFR), urine albumin:creatinine ratio (UACR), and prevalent cardiovascular disease (CVD) in 2571 AAs from the Systolic Blood Pressure Intervention Trial (SPRINT), a trial assessing effects of systolic blood pressure reduction on renal and CVD outcomes. Logistic regression models that adjusted for potentially important confounders tested for association between APOL1 risk variants and baseline clinical CVD (myocardial infarction, coronary, or carotid artery revascularization) and CKD (eGFR under 60 ml/min per 1.73 m(2) and/or UACR over 30 mg/g). AA SPRINT participants were 45.3% female with a mean (median) age of 64.3 (63) years, mean arterial pressure 100.7 (100) mm Hg, eGFR 76.3 (77.1) ml/min per 1.73 m(2), and UACR 49.9 (9.2) mg/g, and 8.2% had clinical CVD. APOL1 (recessive inheritance) was positively associated with CKD (odds ratio 1.37, 95% confidence interval 1.08-1.73) and log UACR estimated slope (β) 0.33) and negatively associated with eGFR (β -3.58), all significant. APOL1 risk variants were not significantly associated with prevalent CVD (1.02, 0.82-1.27). Thus, SPRINT data show that APOL1 risk variants are associated with mild CKD but not with prevalent CVD in AAs with a UACR under 1000 mg/g

Angiogenic Factors in Superimposed Preeclampsia

Imbalances in circulating angiogenic factors contribute to the pathogenesis of preeclampsia. To characterize levels of angiogenic factors in pregnant women with chronic hypertension, we prospectively followed 109 women and measured soluble fms-like tyrosine kinase 1 (sFlt1), soluble endoglin, and placental growth factor at 12, 20, 28, and 36 weeks' gestation and postpartum. Superimposed preeclampsia developed in 37 (34%) and was early onset (&lt;34 weeks) in 9 and later onset (≥34 weeks) in 28. Circulating levels of sFlt1 and the ratio of sFlt1 to placental growth factor were higher before clinical diagnosis at 20 weeks' gestation in women who subsequently developed early onset preeclampsia between 28 and 34 weeks compared with levels in women who never developed preeclampsia ( P =0.001) or who developed late-onset preeclampsia ( P =0.001). Circulating levels of sFlt1, soluble endoglin, and the ratio of sFlt1:placental growth factor were also significantly higher, and placental growth factor levels were significantly lower at the time of clinical diagnosis of superimposed preeclampsia in women with either early or late-onset superimposed preeclampsia compared with levels at similar gestational ages in those with uncomplicated chronic hypertension. We conclude that alterations in angiogenic factors are detectable before and at the time of clinical diagnosis of early onset superimposed preeclampsia, whereas alterations were observed only at the time of diagnosis in women with late-onset superimposed preeclampsia. Longitudinal measurements of angiogenic factors may help anticipate early onset superimposed preeclampsia and facilitate diagnosis of superimposed preeclampsia in women with chronic hypertension. </jats:p

Effects of Intensive Systolic Blood Pressure Control on All-Cause Hospitalizations

Intensive blood pressure control decreases the rate of cardiovascular events by &gt;25% compared with standard blood pressure control. We sought to determine whether the decrease in cardiovascular events seen with intensive blood pressure control is associated with an increased rate of other causes of hospitalization. This is a post hoc analysis of SPRINT (Systolic Blood Pressure Intervention Trial) in 9361 adult participants with hypertension and elevated cardiovascular risk. Participants were randomly assigned to an intensive or standard systolic blood pressure goal (&lt;120 or &lt;140 mm Hg, respectively). The primary outcome was hospitalization rates per 100 person-years for hospitalizations not associated with SPRINT primary events. After excluding hospitalizations linked to SPRINT primary events, there were 4678 participants with a rate of 19.70 hospitalizations per 100 person-years, compared with 4683 participants with a rate of 19.65 ( P =0.37). Equivalence testing shows that these hospitalization rates were statistically equivalent at the P =0.05 level. Of those with hospitalizations, &gt;1 hospitalization was seen in 38.8% of intensive arm participants and 41.9% of standard arm participants ( P =0.08). The mean cumulative count of nonprimary event hospitalizations was comparable between the two arms. The most common causes of hospitalization were cardiovascular (23.6%) followed by injuries, including bone and joint therapeutic procedures (15.7%), infections (12.0%), and nervous systems disorders (10.7%). No categories of hospitalization were statistically more common in the intensive arm compared with the standard arm. Thus, the decrease in cardiovascular events seen with intensive blood pressure control is not associated with an increased rate of other causes of hospitalization. Registration— URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01206062. </jats:sec

The Difference Between Cystatin C– and Creatinine-Based Estimated GFR and Associations With Frailty and Adverse Outcomes: A Cohort Analysis of the Systolic Blood Pressure Intervention Trial (SPRINT)

Rationale &amp; objectiveIn prior research and in practice, the difference between estimated glomerular filtration rate (eGFR) calculated from cystatin C level and eGFR calculated from creatinine level has not been assessed for clinical significance and relevance. We evaluated whether these differences contain important information about frailty.Study designA cohort analysis of the Systolic Blood Pressure Intervention Trial (SPRINT).Setting &amp; participants9,092 hypertensive SPRINT participants who had baseline measurements of serum creatinine, cystatin C, and frailty.ExposureeGFRs calculated using CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equations (eGFRcys and eGFRcr), and eGFRDiff, calculated as eGFRcys-eGFRcr.OutcomesA validated 35-item frailty index that included questionnaire data for general and physical health, limitations of activities, pain, depression, sleep, energy level, self-care, and smoking status, as well as medical history, cognitive assessment, and laboratory data. We defined frailty as frailty index score&gt;0.21 (range, 0-1). The incidence of injurious falls, hospitalizations, cardiovascular events, and mortality was also recorded.Analytical approachWe used logistic regression to model the cross-sectional association of baseline eGFRDiff with frailty among all SPRINT participants. Adjusted proportional hazards regression was used to evaluate the association of eGFRDiff with adverse outcomes and mortality.ResultsMean age was 68±9 (SD) years, mean eGFRcys and eGFRcr were 73±23 and 72±20mL/min/1.73m2, and mean eGFRDiff was 0.5±15mL/min/1.73m2. In adjusted models, each 1-SD higher eGFRDiff was associated with 24% lower odds of prevalent frailty (OR, 0.76; 95% CI, 0.71-0.81), as well as with lower incidence rate of injurious falls (HR, 0.84; 95% CI, 0.77-0.92), hospitalization (HR, 0.91; 95% CI, 0.88-0.95), cardiovascular events (HR, 0.89; 95% CI, 0.81-0.97), and all-cause mortality (HR, 0.71; 95% CI, 0.63-0.82); P&lt;0.01.LimitationsGold-standard measure of kidney function and assessment of muscle mass were not available.ConclusionsThe difference between eGFRcys and eGFRcr is associated with frailty and health status. Positive eGFRDiff is strongly associated with lower risks for longitudinal adverse outcomes and mortality, even after adjusting for chronic kidney disease stage and baseline frailty

APOL1 Renal-Risk Variants Do Not Associate With Incident Cardiovascular Disease or Mortality in the Systolic Blood Pressure Intervention Trial

Relationships between apolipoprotein L1 gene (APOL1) renal-risk variants (RRVs) and cardiovascular disease (CVD) remain controversial. To clarify associations between APOL1 and CVD, a total of 2568 African American Systolic Blood Pressure Intervention Trial (SPRINT) participants were assessed for the incidence of CVD events (primary composite including nonfatal myocardial infarction, acute coronary syndrome not resulting in myocardial infarction, nonfatal stroke, nonfatal acute decompensated heart failure, and CVD death), renal outcomes, and all-cause mortality. Methods: Cox proportional hazards regression models were used, adjusting for age, sex, African ancestry proportion, and treatment group (systolic blood pressure target of <120 mm Hg vs. <140 mm Hg). Results: Of the participants, 14% had 2 APOL1 RRVs; these individuals also had lower baseline estimated GFR and higher levels of albuminuria and BMI. After a median follow-up of 39 months, no significant association was observed between APOL1 RRVs and the primary composite CVD outcome, any of its components, or all-cause mortality (recessive or additive genetic models). APOL1 demonstrated a trend toward association with sustained 30% reduction in estimated GFR to <60 ml/min/1.73 m2 in those with normal kidney function at baseline (hazard ratio 1.64; 95% confidence interval = 0.85−2.93; P = 0.114, recessive model). Discussion: APOL1 RRVs were not associated with incident CVD in high-risk hypertensive, nondiabetic African American participants in SPRINT