Natural history of patients with tuberous sclerosis complex related renal angiomyolipoma

Abstract

Objective: To examine temporal relationships between tuberous sclerosis complex (TSC) and renal angiomyolipoma diagnosis and outcomes, treatment, and healthcare utilization.

Methods: Administrative data from the MarketScan Commercial Database was used to select TSC-related renal angiomyolipoma patients during 1 January 2000–31 March 2013. Patients were followed until the earliest of inpatient death or end of enrollment or study. Occurrence of kidney-related outcomes, kidney-related procedures, and all-cause healthcare utilization and time to occurrence were reported. Kaplan–Meier curves were used to display the unadjusted distribution of time to outcome.

Results: A total of 605 patients were selected (<18 years N = 225; ≥18 years N = 380). Mean time from TSC to renal angiomyolipoma diagnosis was 25.7 months in younger and 16.9 months in older patients. Patients ≥18 years had higher rates of chronic kidney disease (CKD), hematuria, kidney failure, embolization (EMB), and partial and complete nephrectomy compared to patients <18 years (all p < .05). Mean time from TSC-related renal angiomyolipoma diagnosis to CKD, hematuria, kidney failure, EMB, first emergency room and inpatient visits was shorter in older compared to younger patients (all p < .05). Probability of developing CKD was approximately 0.8 and 0.95 within 3 years in younger and older patients, respectively.

Conclusions: Patients with TSC-related renal angiomyolipoma had high rates of kidney-related outcomes and procedures. These events sometimes preceded the angiomyolipoma diagnosis. A key study limitation was that due to the small sample size, results may have been biased by outliers. Research is needed to determine whether earlier angiomyolipoma diagnosis can impact occurrence of events and reduce healthcare utilization.

Keywords:

• Angiomyolipoma
• natural history of disease
• observational study
• tuberous sclerosis

Transparency

Declaration of funding

The study was funded by Novartis Pharmaceutical Corporation.

Author contributions: All authors have contributed to the concept and design of the study. All authors were involved in the drafting of this manuscript and have provided the final approval for its publication.

Declaration of financial/other relationship

Z.L., Q.S. and J.P. have disclosed that they are employees of Novartis. H.C., J.H. and J.B. have disclosed that they are paid consultants to Novartis. X.S., K.C. and C.G. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers on this manuscript have no relevant financial or other relationships to disclose.