A quantitative cross-sectional study of the burden of caring for patients with Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex-associated epilepsy in Japan.

INTRODUCTION: Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), and tuberous sclerosis complex (TSC)-associated epilepsy are rare conditions associated with severe childhood-onset epilepsy. Caregivers play a critical role in the patients' care and may experience significant psychosocial and socioeconomic burden. This cross-sectional study determined the burden of caring for patients with these rare epilepsy conditions in Japan. METHODS: A quantitative online survey was used to assess patients' and caregivers' characteristics and the caregivers' emotional state, among others. Several validated questionnaires were used: the Hospital Anxiety and Depression Scale (HADS; 0-21 score) assessed the caregivers' emotional wellbeing, the Pediatric Quality of Life Inventory Family Impact Module (PedsQL FIM; 0-100 score) assessed the health-related quality of life (HRQoL) of the caregivers and their families, and the Work Productivity and Activity Impairment General Health (WPAI:GH; 0-100 % score) questionnaire assessed work productivity. RESULTS: A total of 36 caregivers responded (median [interquartile range (IQR)] age 43.5 [39.5, 48.3] years; 33/36 [92 %] female; 13/36 [36 %] working part-time and 13/36 [36 %] not working). Participants cared for 7/36 (19 %), 19/36 (53 %), and 10/36 (28 %) patients with LGS, DS, and TSC, respectively (median [IQR] age, 11.0 [6.8, 16.3] years; age at first seizure, 0 [0, 0] years). Patients received a median (IQR) of 4 (3, 5) treatment drug types. Patients experienced median (IQR) 3.0 (0, 21.0) epileptic seizures in the previous week; 28/36 (78 %) had severe intellectual disabilities, and 34/36 (94 %) had developmental delays. Caregivers reported stress (17/36 [47 %]), sleep problems (13/36 [36 %]), and anxiety (12/36 [33 %]). They spent a median (IQR) of 50.0 (17.5, 70.0) hours caregiving in the previous week, with 3.0 (1.0, 11.0) hours of seizure-specific care. Caregivers reported that their lives would be easier with a median (IQR) of 1.5 (0, 5.0) hours fewer per week caring for patients during/following seizures. Median HADS scores were 9.5 ('suspected anxiety diagnosis') and 7.5 ('no depression') for caregivers, and PedsQL FIM Total median score was 60.1, indicating HRQoL impairment for the caregiver and their family. WPAI:GH scores for paid workers indicated important work impairment. Higher caregiving hours (≥ 21 h vs. < 21 h in the previous week) resulted in higher caregiver burden as indicated by the HADS Total score (p = 0.0062) and PedsQL FIM Total score (p = 0.0007). CONCLUSIONS: Caregivers of patients with LGS, DS, or TSC in Japan experience a significant time burden, reduced HRQoL, and high level of work/activity impairment. Caregivers provide round-the-clock care to patients and rely on family and specialized caring services to help manage the increased caregiving time, which tends to be associated with greater emotional burden and HRQoL impact.

Remedial Dosing Recommendations for Sirolimus Delayed or Missed Dosages Caused by Poor Medication Compliance in Pediatric Tuberous Sclerosis Complex Patients.

BACKGROUND: Delayed or missed dosages caused by poor medication compliance significantly affected the treatment of diseases in children. AIMS: The present study aimed to investigate the influence of delayed or missed dosages on sirolimus pharmacokinetics (PK) in pediatric tuberous sclerosis complex (TSC) patients and to recommend remedial dosages for nonadherent patients. METHODS: A published sirolimus population PK model in pediatric TSC patients was used to assess the influence of different nonadherence scenarios and recommend optimally remedial dosages based on Monte Carlo simulation. Thirteen nonadherent scenarios were simulated in this study, including delayed 2h, 4 h, 6 h, 8 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h, 23.5 h, and missed one dosage. Remedial dosing strategies contained 10-200% of scheduled dosages. The optimal remedial dosage was that with the maximum probability of returning the individual therapeutic range. RESULTS: For delayed or missed sirolimus dosages in pediatric TSC patients, when the delayed time was 0-8 h, 8-10 h, 10-18 h, 18-22.7 h, 22.7-24 h, 70%, 60%, 40%, 30%, 20% scheduled dosages were recommended to take immediately. When one dosage was missed, 120% of scheduled dosages were recommended at the next dose. CONCLUSION: It was the first time to recommend remedial dosages for delayed or missed sirolimus therapy caused by poor medication compliance in pediatric TSC patients based on Monte Carlo simulation. Meanwhile, the present study provided a potential solution for delayed or missed dosages in clinical practice.

Treatment guidelines for rare, early-onset conditions associated with epileptic seizures: a literature review on Rett syndrome and tuberous sclerosis complex.

BACKGROUND: Rett syndrome (RTT) and tuberous sclerosis complex (TSC) are two rare disorders presenting with a range of different epileptic seizures. Seizure management requires careful therapy selection, thereby necessitating development of high-quality treatment guidelines. This targeted literature review (TLR) aimed to characterise country-specific and international treatment guidelines available for pharmacological management of seizures in RTT and TSC. METHODS: A TLR was performed between 25-Jan and 11-Mar 2021. Manual searches of online rare disease and guideline databases, and websites of national heath technology assessment bodies were conducted for the following countries: Australia, Canada, France, Germany, Israel, Italy, Japan, Spain, Switzerland, UK, and US as defined by pre-specified eligibility criteria. Search terms were developed for each condition and translated into local languages where appropriate. Eligible publications were defined as guidelines/guidance reporting pharmacological management of seizures in patients with RTT and TSC. Guideline development methodology, geographical focus, author information and treatment recommendations were extracted from guidelines. An author map was generated using R version 3.5.1 to visualise extent of collaboration between authors. RESULTS: 24 total guidelines were included, of which three and six contained only recommendations for RTT and TSC, respectively (some provided recommendations for ≥ 1 condition). Guideline development processes were poorly described (50% [12 guidelines] had unclear/absent literature review methodologies); reported methodologies were variable, including systematic literature reviews (SLRs)/TLRs and varying levels of expert consultation. Most (83% [20/24]) were country-specific, with guideline authors predominantly publishing in contained national groups; four guidelines were classified as 'International,' linking author groups in the US, UK, Italy and France. High levels of heterogeneity were observed in the availability of treatment recommendations across indications, with 13 and 67 recommendations found for RTT and TSC, respectively. For RTT, all treatment recommendations were positive and sodium valproate had the highest number of positive recommendations (Khwaja, Sahin (2011) Curr Opin Pediatr 23(6):633-9). All TSC treatments (21 medications) received either exclusively negative (National Organization for Rare Disorders (2019)) or positive (Chu-Shore et al. (2010) Epilepsia 51(7):1236-41) recommendations; vigabatrin received the highest number of positive recommendations (Kaur, Christodoulou (2019)). CONCLUSIONS: This review highlights the need for the development of international high-quality and comprehensive consensus-based guidance for the management of seizures with pharmacological therapy in RTT and TSC. TRIAL REGISTRATION: Not applicable.

Use of mTOR inhibitors (rapalogs) for the treatment of skin changes in tuberous sclerosis complex.

BACKGROUND: Skin manifestations of Tuberous Sclerosis Complex (TSC) are present in more than 90% of patients. Facial angiofibromas (AF) are considered a skin hallmark of TSC. They are responsible for esthetic impact in patients. We aimed at reviewing the data available on the use of rapamycin (sirolimus) and everolimus for the oral or topical treatment of AF and other TSC-related skin changes and reporting our preliminary experience at Angers University Hospital. METHODS: The literature search has been performed in combining the terms "rapamycin", "sirolimus", "everolimus", "tuberous sclerosis complex", "skin" and "trial". We have splited the findings of the literature search into two parts: 1) the value of rapalogs used systemically for extracutaneous purposes and 2) the role of topical rapalogs used specifically for skin lesions. RESULTS: Large clinical trials using rapamycin or everolimus for the treatment of brain, lung or kidney manifestations of TSC unfortunately poorly define the "skin lesion response rate" they report. Conversely, the trials with topical rapamycin demonstrate significant, albeit transient, efficacy on AF size and visibility and acceptable tolerance. Several trials suggest better efficacy in younger patients than in adults. Long-term evaluation (up to 136 weeks) point to sustained response and good local and systemic tolerance. However, maintenance therapy appears to be mandatory to preserve skin response. Other skin changes, especially shagreen fibrotic plaques, hypomelanotic macules and ungual tumors still need far more research. Our experience in 124 patients (children and adults) treated for facial AF at Angers University Hospital showed that about 80% of them had an impressive and sustained response. CONCLUSION: The issues of cost and access to affordable topical rapamycin formulations are critical for the patients even if skin changes do not cause serious harm in the context of TSC. We strongly suggest to improve and standardize the formulation of topical rapamycin, to encourage the pharmaceutical industry for providing commercial products, and the Health systems (social welfare) to reimburse them. © 2022 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.

Questionnaire-based assessment of sleep disorders in an adult population of Tuberous Sclerosis Complex.

BACKGROUND AND OBJECTIVE: Tuberous Sclerosis Complex (TSC) is a rare systemic disease with a high prevalence of sleep disorders (SD), although they are still largely under-recognized. The objective of this study was to assess the prevalence of SD in adult patients with TSC, and to evaluate the relationship between sleep, epilepsy, and TSC associated neuropsychiatric disorders (TAND). MATERIALS AND METHODS: We administered Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI) and Epworth Sleepiness Scale (ESS) to 114 adult patients referring to different Italian centers. We also collected information on epilepsy and TAND. RESULTS: PSQI, ISI, and ESS revealed a positive score, respectively, in 52 (46.0%), 30 (26.5%), and 16 (14.1%) patients. PSQI was positive in 26.7% of seizure free patients versus 61.9% with active epilepsy (p = 0.003), and the association remained significative applying a multivariate logistic model considering age, antiseizure medications, TAND and nocturnal epileptic seizures (p = 0.02). ISI was positive in 3.3% of seizure free patients versus 41.3% with active epilepsy (p = 0.0004). Applying a multivariate logistic model with the independent variables listed above, the association remained significant (p = 0.007). On the other hand, multivariate logistic model considering active epilepsy as an independent variable, revealed that TAND didn't appear a significant risk factor for positive PSQI (p = 0.43) nor ISI (p = 0.09). CONCLUSIONS: Our results confirmed that SD are highly prevalent in adults with TSC, with active epilepsy acting as a significant risk factor. A careful assessment of sleep, above all in epileptic patients, is of crucial importance.

Renal Neoplasia in Polycystic Kidney Disease: An Assessment of Tuberous Sclerosis Complex-associated Renal Neoplasia and PKD1/TSC2 Contiguous Gene Deletion Syndrome.

To determine the incidence of renal neoplasia among patients undergoing nephrectomy for polycystic kidney disease (PKD), we queried our institutional nephrectomy registry (years 2000-2020). Approximately 4% (231 of 5757) of patients who underwent nephrectomy had PKD, and 26 of these 231 patients (11.3%) had renal neoplasia. Tumors from an additional two patients with PKD were also evaluated. Patients with PKD who had tuberous sclerosis complex (TSC)-associated renal neoplasia were screened for PKD1/TSC2 contiguous gene deletion syndrome (CGS) using single nucleotide polymorphism arrays. The median age of patients with PKD and renal neoplasia at nephrectomy was 54 yr. The median tumor size was 2.0 cm and the tumors were predominantly of low grade and stage. The tumors consisted of 23 renal cell carcinomas (RCCs), one epithelioid angiomyolipoma, and four angiomyolipomas. The median follow-up was 59.5 mo (n = 26) and only one patient with clear cell RCC developed metastases. Two patients with angiomyolipomas had PKD1/TSC2 CGS. Our results support screening of patients with PKD and TSC-associated renal neoplasia as well as TSC patients with cystic renal disease for CGS, as identification of patients with CGS can better define the manifestation and prognosis of CGS and guide counseling regarding patterns of inheritance. PATIENT SUMMARY: We identified patients with abnormal kidney cell growth (called renal neoplasia) among those undergoing removal of kidney tissue for polycystic kidney disease (PKD) and patients with a syndrome involving deletions in two genes, called PKD1/TSC2 contiguous gene deletion syndrome (CGS) at our institution. Of 231 PKD patients with removal of kidney tissue, 11.3% had renal neoplasia, and two patients with angiomyolipoma tumors had PKD1/TSC2 CGS. Detection of renal neoplasia associated with a condition called tuberous sclerosis complex in PKD may increase the identification of patients with PKD1/TSC2 CGS and guide patient counseling regarding outcomes and patterns of inheritance.

Epidemiology, healthcare resource use, and mortality in patients with tuberous sclerosis complex: A population-based study on German health insurance data.

PURPOSE: 10-year retrospective study to assess burden of illness in individuals with tuberous sclerosis complex (TSC) identified from German healthcare data. METHODS: Patients with TSC were identified by International Classification of Diseases code Q85.1. Patients with epilepsy were identified by epilepsy diagnosis or antiseizure medication (ASM) prescription after TSC diagnosis. RESULTS: Using data from 2016 (final study year), 100 patients with TSC were identified (mean [range] age: 38 [1-86] years; male: 40%); prevalence: 7.9 per 100,000 (TSC), 2.2 per 100,000 (TSC with epilepsy). During the 10-year study period (2007-2016), 256 patients with TSC were identified and followed up for 1,784 patient-years (epilepsy: 36%, 616 patient-years). TSC manifestations/comorbidities (apart from epilepsy) were identified more frequently in patients with epilepsy than without. Mean annual healthcare costs for patients with TSC were €6,139 per patient-year (PPY), mostly attributable to medication (35%) and inpatient care (29%). Patients with epilepsy incurred costs more than double those without. Mean (standard deviation [SD]) annual hospitalisation rate (AHR) and length of stay (LOS) PPY: 0.5 (1.0) and 5.9 (18.6) days for TSC. AHR and LOS were greater in patients with epilepsy than without. Mean (SD) number of ASMs prescribed (TSC with epilepsy): 3.0 (2.3) over the entire observable time per patient. Mortality rates (vs. control): 5.08% (vs. 1.69%, p<0.001) for TSC, 7.53% (vs. 0.98%, p<0.001) for TSC with epilepsy, 3.68% (vs. 2.03%, p = 0.003) for TSC without epilepsy. CONCLUSION: Healthcare costs, resource utilisation, and mortality were greater in patients with TSC and epilepsy than those without epilepsy.

Direct and indirect costs and cost-driving factors in adults with tuberous sclerosis complex: a multicenter cohort study and a review of the literature.

BACKGROUND: Tuberous sclerosis complex (TSC) is a monogenetic, multisystem disorder characterized by benign growths due to TSC1 or TSC2 mutations. This German multicenter study estimated the costs and related cost drivers associated with organ manifestations in adults with TSC. METHODS: A validated, three-month, retrospective questionnaire assessed the sociodemographic and clinical characteristics, organ manifestations, direct, indirect, out-of-pocket (OOP), and nursing care-level costs among adult individuals with TSC throughout Germany from a societal perspective (costing year: 2019). RESULTS: We enrolled 192 adults with TSC (mean age: 33.4 ± 12.7 years; range: 18-78 years, 51.6% [n = 99] women). Reported TSC disease manifestations included skin (94.8%) and kidney and urinary tract (74%) disorders, epilepsy (72.9%), structural brain defects (67.2%), psychiatric disorders (50.5%), heart and circulatory system disorders (50.5%), and lymphangioleiomyomatosis (11.5%). TSC1 and TSC2 mutations were reported in 16.7% and 25% of respondents, respectively. Mean direct health care costs totaled EUR 6452 (median EUR 1920; 95% confidence interval [CI] EUR 5533-7422) per patient over three months. Medication costs represented the major direct cost category (77% of total direct costs; mean EUR 4953), and mechanistic target of rapamycin (mTOR) inhibitors represented the largest share (68%, EUR 4358). Mean antiseizure drug (ASD) costs were only EUR 415 (6%). Inpatient costs (8%, EUR 518) and outpatient treatment costs (7%; EUR 467) were important further direct cost components. The mean care grade allowance as an approximator of informal nursing care costs was EUR 929 (median EUR 0; 95% CI EUR 780-1083) over three months. Mean indirect costs totaled EUR 3174 (median EUR 0; 95% CI EUR 2503-3840) among working-age individuals (< 67 years in Germany). Multiple regression analyses revealed mTOR inhibitor use and persistent seizures as independent cost-driving factors for total direct costs. Older age and disability were independent cost-driving factors for total indirect costs, whereas epilepsy, psychiatric disease, and disability were independent cost-driving factors for nursing care costs. CONCLUSIONS: This three-month study revealed substantial direct healthcare, indirect healthcare, and medication costs associated with TSC in Germany. This study highlights the spectrum of organ manifestations and their associated treatment needs in the German healthcare setting. TRIAL REGISTRATION: DRKS, DRKS00016045. Registered 01 March 2019, http://www.drks.de/DRKS00016045 .

Kidney Imaging Surveillance in Commercially Insured Patients With Tuberous Sclerosis Complex.

BACKGROUND: Kidney disease has historically been the primary source of early mortality in adults with tuberous sclerosis complex (TSC). Kidney imaging surveillance promotes early detection of lesions requiring intervention. We describe kidney imaging frequency in relationship to patient-level characteristics for commercially insured patients with TSC in the United States. METHODS: This retrospective observational study used 2003 to 2016 enrollment and claims data from a de-identified fully insured commercial health insurer. Patients with TSC less than 65 years were included. The patient-level kidney imaging rate was calculated as the number of kidney imaging procedures divided by length of continuous enrollment. A multiple linear regression model was used to determine the relationship between imaging rate and progression of TSC-associated kidney disease, number of specialists seen, and nephrologist care. RESULTS: At least half of the 70 patients with TSC included in the study were aged 16 years or younger. Over a follow-up period of up to 14 years, the median kidney imaging rate was 0.13 procedures per year with 43% (N = 30) of patients lacking evidence of kidney imaging during the observation period. Imaging frequency increased with progression of TSC-associated kidney disease, more specialists, and nephrologist care (P < 0.05 for all three in regression model). CONCLUSIONS: A substantial percentage of patients with TSC in the United States are at risk for delayed detection of kidney manifestations due to infrequent kidney imaging surveillance. Multispecialty care, including neurologists, may positively affect kidney surveillance rates.

Economic burden associated with tuberous sclerosis complex in patients with epilepsy.

OBJECTIVES: Data on the economic burden associated with tuberous sclerosis complex (TSC) among patients with epilepsy in the United States (US) are limited. This study aimed to assess all-cause and epilepsy-related healthcare resource utilization (HRU) and healthcare costs in the US among patients with epilepsy and TSC compared with patients with epilepsy but without TSC. METHODS: This retrospective study was conducted using the Symphony Health Solutions claims database (April 1, 2017-June 30, 2019). Patients with ≥1 medical claim with a diagnosis code representing epilepsy or seizures were assigned to the cohort with TSC if they had ≥1 medical claim for TSC; the remaining patients were assigned to the cohort without TSC. Patients in the cohort with TSC were exactly matched 1:5 on demographics to patients in the cohort without TSC. All-cause and epilepsy-related HRU, medical charges, prescription drug costs, and the use of antiepileptic drugs (AEDs) were compared between the matched cohorts over the 1-year study period. RESULTS: A total of 2028 patients with epilepsy and TSC were matched to 10,140 patients with epilepsy but without TSC. Patients with TSC were more likely to have a diagnosis code for refractory epilepsy (38.7% vs. 10.2%, p < 0.001) and more likely to have used an AED (89.5% vs. 71.2%, p < 0.001) than patients without TSC over the study period. On average, patients with TSC received 2.1 distinct AEDs versus 1.3 distinct AEDs among patients without TSC. Compared with patients without TSC, patients with TSC had numerically but not statistically higher incidence rates of all-cause outpatient, clinic, office, and other visits; significantly lower rates of all-cause inpatient and emergency room visits (p < 0.001); and statistically significantly higher incidence rates of epilepsy-related outpatient, inpatient, office, and other visits (p ≤ 0.001). All-cause prescription drug costs were significantly higher among patients with TSC than patients without TSC (cost difference per patient: $14,179, p < 0.001). All-cause medical service charges were numerically higher for patients with TSC, but the differences were not statistically significant (charge difference per patient: $4293 for medical services, p = 0.707). Epilepsy-related costs were significantly higher for patients with TSC; the cost difference per patient was $14,639 for prescription costs (p < 0.001), and the charge difference per patient was $16,838 for medical charges (p = 0.019). CONCLUSION: The results of this study underscore the high epilepsy-related HRU and costs incurred by patients with epilepsy and TSC relative to those incurred by patients with epilepsy but without TSC.

Understanding the health economic burden of patients with tuberous sclerosis complex (TSC) with epilepsy: a retrospective cohort study in the UK Clinical Practice Research Datalink (CPRD).

INTRODUCTION: Epilepsy is highly prevalent in tuberous sclerosis complex (TSC), a multi-system genetic disorder. The clinical and economic burden of this condition is expected to be substantial due to treatment challenges, debilitating co-morbidities and the relationship between TSC-related manifestations. This study estimated healthcare resource utilisation (HCRU) and costs for patients with TSC with epilepsy (TSC+E) in the UK. METHODS: Patients with TSC+E in the Clinical Practice Research Datalink (CPRD) linked to Hospital Episodes Statistics were identified from April 1997 to March 2012. Clinical data were extracted over the entire history, and costs were reported over the most recent 3-year period. HCRU was compared with a matched Comparator cohort, and the key cost drivers were identified by regression modelling. RESULTS: In total, 209 patients with TSC+E were identified, of which 40% recorded ≥2 other primary organ system manifestations and 42% had learning disability. Treatment with ≥2 concomitant antiepileptic drugs (AEDs) was prevalent (60%), potentially suggesting refractory epilepsy. Notwithstanding, many patients with TSC+E (12%) had no record of AED use in their entire history, which may indicate undertreatment for these patients.Brain surgery was recorded in 12% of patients. Routine electroencephalography and MRI were infrequently performed (30% of patients), yet general practitioner visits, hospitalisations and outpatient visits were more frequent in patients with TSC+E than the Comparator. This translated to threefold higher clinical costs (£14 335 vs £4448), which significantly increased with each additional primary manifestation (p<0.0001). CONCLUSIONS: Patients with TSC+E have increased HCRU compared with the general CPRD population, likely related to manifestations in several organ systems, substantial cognitive impairment and severe epilepsy, which is challenging to treat and may be intractable. Disease surveillance and testing appears to be inadequate with few treatments trialled.Multidisciplinary care in TSC clinics with specialist neurologist input may alleviate some of the morbidity of patients, but more innovative treatment and management options should be sought.

Self-injury and aggression in adults with tuberous sclerosis complex: Frequency, associated person characteristics, and implications for assessment.

Even though self-injury and aggression are common in tuberous sclerosis complex (TSC), understanding of these behaviours in adults with TSC and intellectual disability (ID) is limited. Little is known about their frequency in comparison to other ID-related genetic disorders or their association with other TSC-Associated Neuropsychiatric Disorders (TAND). This study determined the caregiver-reported frequency of self-injury and aggression in adults with TSC plus ID in comparison to Down syndrome (DS) and Angelman syndrome (AS), and assessed demographic and behavioural characteristics associated with the occurrence of each behaviour in TSC. Rates of self-injury and aggression in adults with TSC plus ID were 31% and 37.9% respectively. The odds of self-injury for adults with TSC were nearly twice as high as the odds for adults with DS, and the odds of aggression were over 2.5 times higher for adults with TSC than for adults with DS. When compared to adults with AS, odds of self-injury in TSC were around half those of the AS group, and odds of aggression were less than a third of those for adults with AS. These differences were not statistically significant. In adults with TSC, poorer communication and socialisation skills, gastric health problems and impulsivity were associated with self-injury; compulsive behaviour and impulsivity were associated with aggression. Caregivers and professionals should be alert to the likelihood of these behaviours in adults with TSC plus ID, and to characteristics associated with increased risk for their occurrence. We suggest assessment strategies to identify those at elevated risk. WHAT THIS PAPER ADDS: This paper adds specific examination of behavioural difficulties in adults with tuberous sclerosis complex who also have intellectual disability, a population at heightened risk of adverse behavioural outcomes which has received limited focussed examination to date. Findings support existing suggestions that there is relatively high risk for both self-injury and aggression, and provide novel insight into characteristics that may be associated with the presence of these behaviours.

Assessment of Tuberous Sclerosis Complex Associated With Renal Lesions by Targeted Next-generation Sequencing in Mainland China.

OBJECTIVE: To identify the TSC1 and TSC2 mutations in patients with tuberous sclerosis complex (TSC) associated with renal lesions, and to explore the relationship between genotypes and phenotypes. MATERIALS AND METHODS: We analyzed 43 individuals affected with TSC accompanied by renal lesions using next-generation sequencing (NGS). We also performed Sanger sequencing to validate the NGS results. RESULTS: We reported a comprehensive mutation analysis of 43 affected individuals with TSC accompanied by renal lesions using NGS. Forty-one of 43 patients (95%) had at least 1 detectable mutation in the TSC1 or TSC2 gene. We identified 14 novel nucleotide alterations, including 11 novel small mutations and 3 large-deletion mutations for the first time. Our study showed that patients with TSC2 mutations had higher frequency of hypomelanotic macules and dental enamel pits and larger angiomyolipomas (AMLs) than patient populations with non-TSC2 mutations through analysis of the correlated mutation findings with clinical features. CONCLUSION: In conclusion, patients with TSC2 mutations had higher frequency of hypomelanotic macules and dental enamel pits, along with larger renal AMLs, compared with patient populations with non-TSC2 mutations. Patients with large deletions and frameshift mutations of the TSC1 or TSC2 gene showed larger AML diameters than patients with other kinds of mutations.

Healthcare utilization and costs in patients with tuberous sclerosiscomplex-related renal angiomyolipoma.

OBJECTIVE: To quantify healthcare utilization and costs in patients with tuberous sclerosis complex (TSC) and renal angiomyolipoma (AML) in a matched cohort of patients without TSC or AML. METHODS: Administrative data from the MarketScan Research Databases were used to select patients with TSC and renal AML during January 1, 2000-March 31, 2013 from the Commercial database and January 1, 2000-June 30, 2012 from the Medicaid database. Patients were required to have at least 30 days of follow-up from initiation into the study, and were followed until inpatient death, end of insurance coverage, or the end of study. Age, calendar year, and payer-matched controls that had no TSC and no AML were selected. All-cause annualized healthcare utilization and costs were calculated by service category. RESULTS: A total of 218 patients under 18 years and 377 patients 18 years and older with TSC-renal AML were selected from the Commercial database, and matched to 654 and 1,131 controls, respectively. Thirty-eight patients under 18 years and 110 patients 18 years or older with TSC-renal AML were selected from the Medicaid database, and matched to 54 and 212 controls, respectively. Within the Commercial cohort, and across both age groups, TSC-renal AML patients utilized more healthcare services than their matched controls. Within the Medicaid cohort, in both age groups, utilization was higher in TSC-renal AML patients vs control patients for inpatient admissions, emergency room visits, physician office visits, and hospital-based outpatient visits. Across age groups and in both the Commercial and Medicaid cohorts, the annual average total costs were significantly higher in TSC-renal AML patients compared to control patients (p < 0.05 for all). Healthcare costs ranged from $29,240-$48,499 for TSC-renal AML patients and from $2,082-$10,864 for control patients. CONCLUSIONS: Compared to controls, TSC-renal AML patients incurred substantially higher annual healthcare utilization and costs.

Cost-utility analysis of competing treatment strategies for drug-resistant epilepsy in children with Tuberous Sclerosis Complex.

BACKGROUND: The management of drug-resistant epilepsy in children with Tuberous Sclerosis Complex (TSC) is challenging because of the multitude of treatment options, wide range of associated costs, and uncertainty of seizure outcomes. The most cost-effective approach for children whose epilepsy has failed to improve with first-line medical therapy is uncertain. METHODS: A review of MEDLINE from 1990 to 2015 was conducted. A cost-utility analysis, from a third-party payer perspective, was performed for children with drug-resistant epilepsy that had failed to improve with 2 antiseizure drugs (ASDs) and that was amenable to resective epilepsy surgery, across a time-horizon of 5years. Four strategies were included: (1) resective epilepsy surgery, (2) vagus nerve stimulator (VNS) implantation, (3) ketogenic diet, and (4) addition of a third ASD (specifically, carbamazepine). The incremental cost per quality-adjusted life year (QALY) gained was analyzed. RESULTS: Given a willingness-to-pay (WTP) of $100,000 per QALY, the addition of a third ASD ($6600 for a gain of 4.14 QALYs) was the most cost-effective treatment strategy. In a secondary analysis, if the child whose epilepsy had failed to improve with 3 ASDs, ketogenic diet, addition of a fourth ASD, and resective epilepsy surgery were incrementally cost-effective treatment strategies. Vagus nerve stimulator implantation was more expensive yet less effective than alternative strategies and should not be prioritized. CONCLUSIONS: The addition of a third ASD is a universally cost-effective treatment option in the management of children with drug-resistant epilepsy that has failed to improve with 2 ASDs. For children whose epilepsy has failed to improve with 3 ASDs, the most cost-effective treatment depends on the health-care resources available reflected by the WTP.

Effect of Angiofibromas on Quality of Life and Access to Care in Tuberous Sclerosis Patients and Their Caregivers.

BACKGROUND/OBJECTIVES: Facial angiofibromas (AF) have the potential to cause disfigurement in children with tuberous sclerosis complex (TSC). Facial disfigurement can impact the quality of life (QoL) of individuals and their families, leading to negative psychosocial outcomes. QoL has not been studied in TSC patients with AF. METHODS: We conducted a cross-sectional survey study to investigate QoL of TSC patients with AF and their caregivers and to explore the current state of access to treatment for AF. TSC patients and caregivers in TSC clinic at Boston Children's Hospital and through the Tuberous Sclerosis Alliance were recruited to complete QoL surveys including the CADIS, CDLQI, and Skindex-teen questionnaires, and a survey on access to treatment of AF. RESULTS: Fifty-eight patients with TSC and 161 caregivers participated in the study. Caregivers of patients with AF had significantly poorer QoL scores compared to caregivers of those without AF, as measured by a modified CADIS questionnaire (mean 31.7 vs. 11.7, p = 0.004). Among patients with AF, those who received treatment had significantly better QoL scores compared with those without treatment, as measured by the CDLQI (mean 3.8 vs. 9.5, p = 0.001). Forty-one and two-tenths percent of subjects reported never receiving treatment for AF. Forty-seven and three-tenths percent of subjects were prescribed topical rapamycin, 47.7% of whom experienced difficulty with insurance coverage. CONCLUSIONS: Presence and lack of treatment of AF significantly impacts QoL in TSC patients and their caregivers. Access to care for AF is limited by multiple factors and should be addressed by clinicians working with this patient population.

Kidney involvement in tuberous sclerosis complex: the impact on healthcare resource use and costs.

OBJECTIVE: Tuberous sclerosis complex (TSC) is associated with non-malignant kidney lesions-angiomyolipomata-that may be associated with chronic kidney disease (CKD). This study investigated the relationship between renal angiomyolipomata and CKD in TSC, including the impact on healthcare resource utilization (HCRU) and costs. METHODS: This was a retrospective, longitudinal cohort study based on medical record data spanning January 1990-April 2012 for 369 TSC patients treated at a specialty center in the Netherlands. Cohorts were established based on CKD stage and angiomyolipoma size. Rates of HCRU (physician visits, monitoring, and interventions) were compared across cohorts using rate ratios. Healthcare costs were compared across cohorts using cost differences. Regression models were used to identify predictive factors for HCRU and healthcare costs. RESULTS: Sixteen per cent of patients reached CKD stage 3 or higher during follow-up. Patients at more advanced stages of CKD more frequently had either large or multiple small angiomyolipomata and higher HCRU rates and healthcare costs. In the multivariate analyses, male gender, CKD stage >1, angiomyolipoma size ≥3.5 cm, embolization, and the presence of moderate or severe lymphangioleiomyomatosis (LAM) were associated with greater HCRU (p ≤ 0.002 for all comparisons). Definite (vs suspected) TSC diagnosis, CKD stage 5 (vs CKD stage 1), angiomyolipoma size ≥3.5 cm, and moderate or severe LAM were associated with higher costs (p = 0.050 for TSC diagnosis, p ≤ 0.002 for other comparisons). Costs in CKD stage 5 were driven primarily by dialysis. CONCLUSIONS: A substantial proportion of patients with TSC developed moderate-to-severe CKD, which was associated with renal angiomyolipomata and increased HCRU and costs.