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.

Pertechnetate scintigraphy in primary congenital hypothyroidism

Primary congenital hypothyroidism (PCH) is currently detected effectively by heel-stick screening. When elevated thyrotropin (TSH) and/or decreased T4 are found in the blood of neonates, they are recalled, values are confirmed in venous blood and thyroxine replacement therapy (TRT) is immediately instituted, thus cretinism or severe retardation is prevented. However, in a significant percentage of neonates with abnormal blood levels of T4 or TSH, the disorder is transient. To help determine the exact cause of PCH and the possibility of transient PCH, pinhole thyroid imaging is performed 30 min after an intravenous injection of 18.5 MBq (500 microCi) 99mTc-pertechnetate (TcPT). Patients with a nonvisualized gland or patients with images suggesting dyshormonogenesis are reevaluated at age 3-4 y to exclude transient PCH.

METHODS

To define the role of TcPT imaging in determining the exact etiology of PCH and the possibility of its being transient, we reviewed data from 103 neonates with PCH who had scintigraphy in our laboratory between 1970 and 1996 and we correlated the results with clinical outcome.

RESULTS

Four patterns of thyroid scintigrams were recognized and these determined patient classification: (a) normal in 7 patients with false-positive heel-stick screening but normal venous blood hormone levels; (b) hypoplasia-ectopia in 32 patients requiring lifelong TRT; (c) nonvisualization in 35 patients-32 with agenesis requiring lifelong TRT and 3 with fetal thyroid suppression by maternal antibodies whose TRT was discontinued at a later age; and (d) dyshormonogenesis (markedly increased TcPT concentration) in 29 patients-25 with permanent PCH requiring lifelong TRT and 4 with transient PCH in whom TRT was discontinued. Of the 25 patients with dyshormonogenesis, 12 belonged to five families with two or three siblings having the same disorder.

CONCLUSION

TcPT thyroid scintigraphy in the neonate with PCH provides a more specific diagnosis, is useful for selecting patients for re-evaluation to uncover transient PCH and discontinue TRT and defines dyshormonogenesis, which is familial and requires genetic counseling. It is also cost-effective.

Clinical, biochemical, and molecular investigations of a genetic isolate of growth hormone insensitivity (Laron's syndrome)

We have characterized the GH receptor mutation that is responsible for extreme short stature and GH insensitivity in a Bahamian genetic isolate. Heights of affected individuals ranged from -4.0 to -6.3 SD. Like others with Laron's syndrome, they had normal to high serum GH concentrations and low serum insulin-like growth factor I concentrations. Circulating levels of GH-binding protein activity were below limits of detection. Amplification of exons 2-7 and screening with single strand conformational polymorphism analysis located an abnormality in exon 7. Sequencing identified homozygosity for a C to T transition in the third position of codon 236. Reverse transcription and PCR amplification of complementary DNA from lymphocytes showed that this same sense mutation generated a new splice donor site 63 bp 5' to the normal exon 7 splice site. This novel site was used to the exclusion of the normal site in homozygotes. Both normal and variant messenger ribonucleic acid species were detected in heterozygotes. The predicted protein lacks 21 amino acids, including those defining the WS-like motif of the GH receptor extracellular domain. The high frequency of Laron's syndrome in this isolated island population probably reflects the introduction of the G236 splice mutation by a settler early in the 300-yr history of English settlement.

Effect of intravenous insulin-like growth factor I in two patients with leprechaunism

Leprechaunism (Donohue syndrome) is an autosomal recessive disorder characterized by hyperglycemia, extreme insulin resistance, dysmorphic features, failure to thrive, and early death. In this study, recombinant IGF-I, which has both insulin-like and anabolic effects, was administered to two infants with leprechaunism in an attempt to reduce hyperglycemia and improve nutritional status. IGF-I was infused for 66 h in patient FL-1 and 62 h in patient NC-2, with maximal infusion rates of 110 and 40 micrograms/kg/h, respectively. Although supraphysiologic concentrations of IGF-I were achieved (459 and 1583 micrograms/L in FL-1 and NC-2, respectively), there were no apparent glucose-lowering or nitrogen-sparing effects. Insulin concentrations decreased from extremely high values (16804 and 10224 pmol/L) but remained elevated (611 pmol/L in FL-1 and 5869 pmol/L in NC-2). No changes in serum and urinary urea nitrogen or electrolytes occurred. IGF binding protein-2, which was the predominant IGF binding protein in serum by ligand blot and immunoblot, did not change with IGF-I infusion. IGF binding protein-3 levels were low at baseline and increased slightly during the infusion. We hypothesize that the lack of significant glucose-lowering and anabolic responses to IGF-I could be secondary to a postreceptor defect in IGF-I signaling resulting from the absence of functional insulin receptors.

Cardiovascular correlates of the psychotherapeutic process

12 medical student volunteers were studied during 10 weekly sessions of brief dynamic psychotherapy using on-line physiological monitoring and concurrent psychotherapy process ratings. Forearm vascular resistance change from baseline for each visit was found to be related to psychotherapeutic outcome, and to some of the process variables, but to be most strongly correlated with clusters of process variables. This suggests that there may yet be a role for physiological monitoring in psychotherapy research.

Aging, terminal decline, and terminal drop

Data from a 20-year longitudinal study of persons over 60 were analyzed by step-wise multiple regression to test for declines in function with age, for terminal decline (linear relationship to time before death), and for terminal drop (curvilinear relationship to time before death). There were no substanial terminal drop effects. All health measures had substantial declines with age, and the physician's physical function rating, as well as the individual's self-rating, showed additional terminal decline. Intelligence had a substantial decline with age and a small terminal decline. Most activities declined with age but had no significant terminal decline. Despite these declines in health, intelligence, and activities, there was little or no decline in satisfaction or adjustment.