Browsing by Author "Zhao, Yang"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Genotype-Guided Hydralazine Therapy
    (Karger, 2020) Collins, Kimberly S.; Raviele, Anthony L.J.; Elchynski, Amanda L.; Woodcock, Alexander M.; Zhao, Yang; Cooper-DeHoff, Rhonda M.; Eadon, Michael T.; Medicine, School of Medicine
    Background: Despite its approval in 1953, hydralazine hydrochloride continues to be used in the management of resistant hypertension, a condition frequently managed by nephrologists and other clinicians. Hydralazine hydrochloride undergoes metabolism by the N-acetyltransferase 2 (NAT2) enzyme. NAT2 is highly polymorphic as approximately 50% of the general population are slow acetylators. In this review, we first evaluate the link between NAT2 genotype and phenotype. We then assess the evidence available for genotype-guided therapy of hydralazine, specifically addressing associations of NAT2 acetylator status with hydralazine pharmacokinetics, antihypertensive efficacy, and toxicity. Summary: There is a critical need to use hydralazine in some patients with resistant hypertension. Available evidence supports a significant link between genotype and NAT2 enzyme activity as 29 studies were identified with an overall concordance between genotype and phenotype of 92%. The literature also supports an association between acetylator status and hydralazine concentration, as fourteen of fifteen identified studies revealed significant relationships with a consistent direction of effect. Although fewer studies are available to directly link acetylator status with hydralazine antihypertensive efficacy, the evidence from this smaller set of studies is significant in 7 of 9 studies identified. Finally, 5 studies were identified which support the association of acetylator status with hydralazine-induced lupus. Clinicians should maintain vigilance when prescribing maximum doses of hydralazine. Key Messages: NAT2 slow acetylator status predicts increased hydralazine levels, which may lead to increased efficacy and adverse effects. Caution should be exercised in slow acetylators with total daily hydralazine doses of 200 mg or more. Fast acetylators are at risk for inefficacy at lower doses of hydralazine. With appropriate guidance on the usage of NAT2 genotype, clinicians can adopt a personalized approach to hydralazine dosing and prescription, enabling more efficient and safe treatment of resistant hypertension.
  • Thumbnail Image
    Item
    Real-World Clinical and Healthcare Resource Burden Among Burosumab-Naïve Patients With Familial Hypophosphatemia
    (Oxford University Press, 2024-10-24) Imel, Erik A.; Li, Zhiyi; Heerssen, Heather M.; Princic, Nicole; Schwartz, Hana; Zhao, Yang; Dahir, Kathryn M.; Medicine, School of Medicine
    Objective: To examine the real-world clinical and healthcare resource burden of familial hypophosphatemia (FH). Methods: In a retrospective, observational cohort study using MarketScan claims data from 2017 to 2021, clinical characteristics and healthcare resource utilization (HCRU) and costs were compared between burosumab-naïve pediatric and adult patients with ≥ 1 FH diagnosis code and matched controls without FH. Patient characteristics were evaluated at baseline, and disease characteristics, HCRU, and costs were evaluated over a 12-month follow-up period. Outcomes were analyzed descriptively. Costs were additionally analyzed using multivariate regression models. Results: Overall, 570 patients with FH and 1710 non-FH matched controls were included. Approximately 10% of study participants were aged < 18 years. Patients with FH had 7.8-fold higher mean baseline comorbidity (Charlson Comorbidity Index). The prevalence of morbidities over the 12-month follow-up period was higher in patients with FH than controls, including renal disease (33% vs 3%), arthralgia (25% vs 10%), osteoarthritis (17% vs 6%), and delayed growth/walking difficulty (16% vs 2%; all P < .001). All-cause HCRU was significantly greater for patients with FH than controls over follow-up, including the proportion of patients with at least one inpatient admission (60% vs 4%), outpatient emergency room visit (52% vs 16%), and outpatient pharmacy prescription (96% vs 71%; all P < .001). The mean annual total healthcare cost per patient was also 22.6-fold higher for patients with FH than controls (adjusted cost difference = $129 643; P < .001). Differences were apparent across all age groups. Conclusion: Compared with non-FH matched controls, burosumab-naïve patients with FH experienced multiple morbidities and had substantially higher HCRU and costs.