NEJM original articles

Background. For patients with asymptomatic severe aortic stenosis and preserved left ventricular ejection fraction, current guidelines recommend routine clinical surveillance every 6 to 12 months. Data from randomized trials examining whether early intervention with transcatheter aortic-valve replacement (TAVR) will improve outcomes in these patients are lacking.

Methods. At 75 centers in the United States and Canada, we randomly assigned, in a 1:1 ratio, patients with asymptomatic severe aortic stenosis to undergo early TAVR with transfemoral placement of a balloon-expandable valve or clinical surveillance. The primary end point was a composite of death, stroke, or unplanned hospitalization for cardiovascular causes. Superiority testing was performed in the intention-to-treat population.

Results. A total of 901 patients underwent randomization; 455 patients were assigned to TAVR and 446 to clinical surveillance. The mean age of the patients was 75.8 years, the mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 1.8% (on a scale from 0 to 100%, with higher scores indicating a greater risk of death within 30 days after surgery), and 83.6% of patients were at low surgical risk. A primary end-point event occurred in 122 patients (26.8%) in the TAVR group and in 202 patients (45.3%) in the clinical surveillance group (hazard ratio, 0.50; 95% confidence interval, 0.40 to 0.63; P<0.001). Death occurred in 8.4% of the patients assigned to TAVR and in 9.2% of the patients assigned to clinical surveillance, stroke occurred in 4.2% and 6.7%, respectively, and unplanned hospitalization for cardiovascular causes occurred in 20.9% and 41.7%. During a median follow-up of 3.8 years, 87.0% of patients in the clinical surveillance group underwent aortic-valve replacement. There were no apparent differences in procedure-related adverse events between patients in the TAVR group and those in the clinical surveillance group who underwent aortic-valve replacement.

Conclusions. Among patients with asymptomatic severe aortic stenosis, a strategy of early TAVR was superior to clinical surveillance in reducing the incidence of death, stroke, or unplanned hospitalization for cardiovascular causes. (Funded by Edwards Lifesciences; EARLY TAVR ClinicalTrials.gov number, NCT03042104.).

Background. Apolipoprotein L1 gene (APOL1) variants are risk factors for chronic kidney disease (CKD) among Black Americans. Data are sparse on the genetic epidemiology of CKD and the clinical association of APOL1 variants with CKD in West Africans, a major group in the Black population.

Methods. We conducted a case-control study involving participants from Ghana and Nigeria who had CKD stages 2 through 5, biopsy-proven glomerular disease, or no kidney disease. We analyzed the association of CKD with APOL1 variants among participants with high-risk genotypes (two APOL1 risk alleles) and those with low-risk genotypes (fewer than two APOL1 risk alleles) by fitting logistic-regression models that controlled for covariates, including clinical site, age, and sex.

Results. Among 8355 participants (4712 with CKD stages 2 through 5, 866 with glomerular diseases, and 2777 with no kidney disease), the prevalence of monoallelic APOL1 variants was 43.0% and that of biallelic APOL1 variants was 29.7%. Participants with two APOL1 risk alleles had higher odds of having CKD than those with one risk allele or no risk alleles (adjusted odds ratio, 1.25; 95% confidence interval [CI], 1.11 to 1.40), as well as higher odds of focal segmental glomerulosclerosis (adjusted odds ratio, 1.84; 95% CI, 1.30 to 2.61). Participants with one APOL1 risk allele had higher odds of having CKD than those with no risk alleles (adjusted odds ratio, 1.18; 95% CI, 1.04 to 1.33), as well as higher odds of focal segmental glomerulosclerosis (adjusted odds ratio, 1.61; 95% CI, 1.04 to 2.48). The inclusion of covariates did not modify the association of monoallelic and biallelic APOL1 variants with CKD or focal segmental glomerulosclerosis.

Conclusions. In this study, monoallelic APOL1 variants were associated with 18% higher odds of CKD and 61% higher odds of focal segmental glomerulosclerosis; biallelic APOL1 variants were associated with 25% higher odds of CKD and 84% higher odds of focal segmental glomerulosclerosis. (Funded by the National Human Genome Research Institute and others.).

Background. Zoledronate prevents fractures in older women when administered every 12 to 18 months, but its effects on bone density and bone turnover persist beyond 5 years. Whether infrequent zoledronate administration would prevent vertebral fractures in early postmenopausal women is unknown.

Methods. We conducted a 10-year, prospective, double-blind, randomized, placebo-controlled trial involving early postmenopausal women (50 to 60 years of age) with bone mineral density T scores lower than 0 and higher than -2.5 (scores of -1 or higher typically indicate normal bone mineral density) at the lumbar spine, femoral neck, or hip. Participants were randomly assigned to receive an infusion of zoledronate at a dose of 5 mg at baseline and at 5 years (zoledronate-zoledronate group), zoledronate at a dose of 5 mg at baseline and placebo at 5 years (zoledronate-placebo group), or placebo at both baseline and 5 years (placebo-placebo group). Spinal radiographs were obtained at baseline, 5 years, and 10 years. The primary end point was morphometric vertebral fracture, which was assessed semiquantitatively and defined as at least a 20% change in vertebral height from that seen on the baseline radiograph. Secondary end points were fragility fracture, any fracture, and major osteoporotic fracture.

Results. Of 1054 women with a mean age of 56.0 years at baseline, 1003 (95.2%) completed 10 years of follow-up. A new morphometric fracture occurred in 22 women (6.3%) in the zoledronate-zoledronate group, in 23 women (6.6%) in the zoledronate-placebo group, and in 39 women (11.1%) in the placebo-placebo group (relative risk, zoledronate-zoledronate vs. placebo-placebo, 0.56 [95% confidence interval {CI}, 0.34 to 0.92; P = 0.04]; and zoledronate-placebo vs. placebo-placebo, 0.59 [95% CI, 0.36 to 0.97; P = 0.08]). The relative risk of fragility fracture, any fracture, and major osteoporotic fracture was 0.72 (95% CI, 0.55 to 0.93), 0.70 (95% CI, 0.56 to 0.88), and 0.60 (95% CI, 0.42 to 0.86), respectively, when zoledronate-zoledronate was compared with placebo-placebo and 0.79 (95% CI, 0.61 to 1.02), 0.77 (95% CI, 0.62 to 0.97), and 0.71 (95% CI, 0.51 to 0.99), respectively, when zoledronate-placebo was compared with placebo-placebo.

Conclusions. Ten years after trial initiation, zoledronate administered at baseline and 5 years was effective in preventing morphometric vertebral fracture in early postmenopausal women. (Funded by the Health Research Council of New Zealand; Australian New Zealand Clinical Trials Registry number, ACTRN12612000270819.).

Background. Patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer with residual invasive disease after neoadjuvant systemic therapy have a high risk of recurrence and death. The primary analysis of KATHERINE, a phase 3, open-label trial, showed that the risk of invasive breast cancer or death was 50% lower with adjuvant trastuzumab emtansine (T-DM1) than with trastuzumab alone.

Methods. We randomly assigned patients with HER2-positive early breast cancer with residual invasive disease in the breast or axilla after neoadjuvant systemic treatment with taxane-based chemotherapy and trastuzumab to receive T-DM1 or trastuzumab for 14 cycles. Here, we report the prespecified final analysis of invasive disease-free survival and the second interim analysis of overall survival.

Results. With a median follow-up of 8.4 years, T-DM1 sustained the improvement in invasive disease-free survival over trastuzumab (unstratified hazard ratio for invasive disease or death, 0.54; 95% confidence interval [CI], 0.44 to 0.66). Seven-year invasive disease-free survival was 80.8% with T-DM1 and 67.1% with trastuzumab (difference, 13.7 percentage points). T-DM1 also led to a significantly lower risk of death than trastuzumab (unstratified hazard ratio, 0.66; 95% CI, 0.51 to 0.87; P = 0.003). Seven-year overall survival was 89.1% with T-DM1 and 84.4% with trastuzumab (difference, 4.7 percentage points). Adverse events of grade 3 or higher were noted in 26.1% of the patients in the T-DM1 group and 15.7% of those in the trastuzumab group.

Conclusions. As compared with trastuzumab, T-DM1 improved overall survival with sustained improvement in invasive disease-free survival among patients with HER2-positive early breast cancer with residual invasive disease after neoadjuvant therapy. (Funded by F. Hoffmann-La Roche/Genentech; KATHERINE ClinicalTrials.gov number, NCT01772472.).