N-terminal prohormone brain natriuretic peptide as a predictor of cardiovascular disease and mortality in blacks with hypertensive kidney disease: the African American Study of Kidney Disease and Hypertension (AASK)

BACKGROUND

Higher levels of N-terminal prohormone brain-type natriuretic peptide (NT-proBNP) predict cardiovascular disease (CVD) in several disease states, but few data are available in patients with chronic kidney disease or in blacks.

METHODS AND RESULTS

The African American Study of Kidney Disease and Hypertension trial enrolled hypertensive blacks with a glomerular filtration rate of 20 to 65 mL x min(-1) x 1.73 m(-2) and no other identified cause of kidney disease. NT-proBNP was measured with a sandwich chemiluminescence immunoassay (coefficient of variation 2.9%) in 994 African American Study of Kidney Disease and Hypertension participants. NT-proBNP was categorized as undetectable, low, moderate, or high. Proteinuria was defined as 24-hour urinary protein-creatinine ratio >0.22. A total of 134 first CVD events (CVD death or hospitalization for coronary artery disease, heart failure, or stroke) occurred over a median of 4.3 years. Participants with high NT-proBNP were much more likely to have a CVD event than participants with undetectable NT-proBNP after adjustment (relative hazard 4.0 [95% confidence interval [CI] 2.1 to 7.6]). A doubling of NT-proBNP was associated with a relative hazard of 1.3 (95% CI 1.0 to 1.6) for coronary artery disease, 1.7 (95% CI 1.4 to 2.2) for heart failure, 1.1 (95% CI 0.9 to 1.4) for stroke, and 1.8 (95% CI 1.4 to 2.4) for CVD death. The association of NT-proBNP with CVD events was significantly stronger (P(interaction)=0.05) in participants with than in those without proteinuria. Higher NT-proBNP was not associated with renal disease progression.

CONCLUSIONS

These results suggest that elevated NT-proBNP levels are associated with higher CVD risk among blacks with hypertensive kidney disease. This association may be stronger in individuals with significant proteinuria.

Effect of ramipril vs amlodipine on renal outcomes in hypertensive nephrosclerosis: a randomized controlled trial

CONTEXT

Incidence of end-stage renal disease due to hypertension has increased in recent decades, but the optimal strategy for treatment of hypertension to prevent renal failure is unknown, especially among African Americans.

OBJECTIVE

To compare the effects of an angiotensin-converting enzyme (ACE) inhibitor (ramipril), a dihydropyridine calcium channel blocker (amlodipine), and a beta-blocker (metoprolol) on hypertensive renal disease progression.

DESIGN, SETTING, AND PARTICIPANTS

Interim analysis of a randomized, double-blind, 3 x 2 factorial trial conducted in 1094 African Americans aged 18 to 70 years with hypertensive renal disease (glomerular filtration rate [GFR] of 20-65 mL/min per 1.73 m(2)) enrolled between February 1995 and September 1998. This report compares the ramipril and amlodipine groups following discontinuation of the amlodipine intervention in September 2000.

INTERVENTIONS

Participants were randomly assigned to receive amlodipine, 5 to 10 mg/d (n = 217), ramipril, 2.5 to 10 mg/d (n = 436), or metoprolol, 50 to 200 mg/d (n = 441), with other agents added to achieve 1 of 2 blood pressure goals.

MAIN OUTCOME MEASURES

The primary outcome measure was the rate of change in GFR; the main secondary outcome was a composite index of the clinical end points of reduction in GFR of more than 50% or 25 mL/min per 1.73 m(2), end-stage renal disease, or death.

RESULTS

Among participants with a urinary protein to creatinine ratio of >0.22 (corresponding approximately to proteinuria of more than 300 mg/d), the ramipril group had a 36% (2.02 [SE, 0.74] mL/min per 1.73 m(2)/y) slower mean decline in GFR over 3 years (P =.006) and a 48% reduced risk of the clinical end points vs the amlodipine group (95% confidence interval [CI], 20%-66%). In the entire cohort, there was no significant difference in mean GFR decline from baseline to 3 years between treatment groups (P =.38). However, compared with the amlodipine group, after adjustment for baseline covariates the ramipril group had a 38% reduced risk of clinical end points (95% CI, 13%-56%), a 36% slower mean decline in GFR after 3 months (P =.002), and less proteinuria (P<.001).

CONCLUSION

Ramipril, compared with amlodipine, retards renal disease progression in patients with hypertensive renal disease and proteinuria and may offer benefit to patients without proteinuria.

Office education by pediatricians to increase seat belt use

We studied promoting seat belt use by school-aged children through discussions with their pediatricians. The study population consisted of 242 well children observed coming to and leaving from a private pediatric practice. Only four (5%) of 73 control patients who did not wear their seat belts coming in wore them going out. For intervention patients, this figure was 29 (38%) of 77. At one-year follow-up by questionnaire, there were no statistical differences between the percentage of seat belt use in control (67%) vs intervention (62%) patients. However, pediatricians' reported percentage of patients routinely counseled about seat belt use prior to the start of the study was highly correlated with patients' observed prestudy seat belt use. Pediatricians should include education about automobile safety as a part of all well-child visits.

The anterior cervical plate

The anterior cervical plate was employed routinely in 13 anterior cervical fusions in adults at the Medical Center Hospital of Vermont (MCHV) from October 1979 to December 1980. A method for installation of the implant is presented. Review of these patients shows that the 11 survivors have satisfactory alignment of their cervical spines, with adequately evolving fusions. Technical problems include plate position and screw depth. This demanding method is now reserved for special indications.

Early and late repair of lateral ligament of the ankle

Utilizing an apparatus for separately testing the status of the anterior talofibular and the calaneofibular ligaments of the ankle in 25 healthy, 15- to 30-year-old adults, it became apparent that the stability of the ankle depends primarily upon the integrity of the anterior talofibular ligament. When the "fore n' aft" stress measurement exceeds 4 mm, a positive anterior drawer test is elicited, and the ankle ligament needs surgical repair. Tibial talar tilt normals ranged up to 18 degrees. Repair (early and late) is accomplished by suturing what one finds (there is always some ligament present) and reinforcing the anterior talofibular ligament repair with overlap of the nearby lateral talocalcaneal ligament plus the marginal ankle retinaculum. Four weeks in a plaster of paris walking cast are followed by use of Ace bandages of 2 weeks. Light activity is begun 6 weeks after repair, and activity of choice is begun 8 weeks after repair. Repeat stress testing is performed at 3 months postsurgery, and a questionnaire is completed at the same time. On a point system (1 to 10) reviewing pain, stability, and swelling, the results in 50 cases rate from 8 to 10, with a lower rating improving with more time. Surgical time is approximately 30 minutes. There seems to be no need for more radical surgery utilizing other muscles. The senior author has employed this surgery for the past 19 years with approximately 165 cases. Only 50 patients with proper 3-month postoperative stress testing and questionnaire follow-up, who were operated upon 1 or more years ago, area recorded here.

Early and late repair of lateral ligament of the ankle

Utilizing an apparatus for separately testing the status of the anterior talofibular and the calaneofibular ligaments of the ankle in 25 healthy, 15- to 30-year-old adults, it became apparent that the stability of the ankle depends primarily upon the integrity of the anterior talofibular ligament. When the "fore n' aft" stress measurement exceeds 4 mm, a positive anterior drawer test is elicited, and the ankle ligament needs surgical repair. Tibial talar tilt normals ranged up to 18 degrees. Repair (early and late) is accomplished by suturing what one finds (there is always some ligament present) and reinforcing the anterior talofibular ligament repair with overlap of the nearby lateral talocalcaneal ligament plus the marginal ankle retinaculum. Four weeks in a plaster of paris walking cast are followed by use of Ace bandages of 2 weeks. Light activity is begun 6 weeks after repair, and activity of choice is begun 8 weeks after repair. Repeat stress testing is performed at 3 months postsurgery, and a questionnaire is completed at the same time. On a point system (1 to 10) reviewing pain, stability, and swelling, the results in 50 cases rate from 8 to 10, with a lower rating improving with more time. Surgical time is approximately 30 minutes. There seems to be no need for more radical surgery utilizing other muscles. The senior author has employed this surgery for the past 19 years with approximately 165 cases. Only 50 patients with proper 3-month postoperative stress testing and questionnaire follow-up, who were operated upon 1 or more years ago, area recorded here.

Ankle instability: evaluation of the lateral ligaments

Bilateral ankle stress testing was performed on 25 subjects in a device which controlled position of the foot and the amount of force applied during the examination. Both inversion testing in the anteroposterior plane and anterior drawer testing in the lateral plane were performed in the same group of symptom-free patients. The reproducibility of the test was demonstrated. Previous history of injury, left vs. right handedness, side and anthropometric measurements did not affect the test. There was no difference in the inversion test between ankles tested in neutral and plantar flexion. In functionally normal ankles, the range of inversion "talar tilt" was 0 to 18 degrees while the maximum of anterior displacement on drawer testing was 3 mm. The effective stiffness of the anterior talofibular ligament was thus computed as 65 +/- 34 N/m. Anterior drawer testing appears to evaluate lateral ligamentous integrity of the ankle more critically than the talar tilt test.