Cost-effectiveness of angiotensin-converting enzyme inhibitors versus angiotensin II receptor blockers as first-line treatment in autosomal dominant polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a rare kidney disorder impacting ∼1:2,500 individuals among the general US population. Hypertension is a significant predictor of ADPKD progression, and a risk factor for development of cardiovascular disease (CVD), the most common cause for mortality among ADPKD patients. Angiotensin-converting enzymes inhibitors (ACE-I) are widely used as first-line treatment in ADPKD for the management of hypertension. However, their cost-effectiveness relative to other hypertensive medications, such as angiotensin II receptor blockers (ARB), has never been assessed. OBJECTIVE: To determine if ARB are more cost-effective than ACE-Is as first-line treatment in ADPKD. METHODS: A Markov-state decision model was constructed for estimation of cost and outcome benefits in hypertensive ADPKD patients. Transition probabilities were extrapolated from a retrospective cohort study comparing chronic kidney disease (CKD) stage transitions in ADPKD patients. Annual pharmaceutical costs per average daily dose per CKD stage were extracted from a US healthcare claims database. Median total healthcare costs per CKD stage or transplant were extracted from the published literature. The time horizon was set to 30 years, with 1-year duration to cycle shift. A cost-effectiveness analysis was conducted to estimate the incremental cost-effectiveness ratio (ICER) of ACE-I vs ARB per additional year of prevented transplant and/or death. A one-way probabilistic sensitivity analysis was conducted, with 10% variation in probabilities and cost. RESULTS: Total annual healthcare costs accrued after 30 years among ADPKD patients taking ACE-Is was estimated to be $3,505,028.41, compared to ARB at $3,644,327.65. Life expectancy was increased by 1.39 years among patients taking ACE-I. Approximate 10-year survival in patients taking ACE-Is was 47% compared to ARB at 34%. CONCLUSIONS: ACE-I dominated ARB and displayed greater cost-effectiveness due to lower cost and increased capacity to prolong years of life without transplant or death among hypertensive ADPKD patients. This model strengthens the value of ACE-I over ARB as first-line treatment for hypertension management in ADPKD patients.

Assessing standardization of molecular testing for non-small-cell lung cancer: results of a worldwide external quality assessment (EQA) scheme for EGFR mutation testing.

BACKGROUND: The external quality assurance (EQA) process aims at establishing laboratory performance levels. Leading European groups in the fields of EQA, Pathology, and Medical and Thoracic Oncology collaborated in a pilot EQA scheme for somatic epidermal growth factor receptor (EGFR) gene mutational analysis in non-small-cell lung cancer (NSCLC). METHODS: EQA samples generated from cell lines mimicking clinical samples were provided to participating laboratories, each with a mock clinical case. Participating laboratories performed the analysis using their usual method(s). Anonymous results were assessed and made available to all participants. Two subsequent EQA rounds followed the pilot scheme. RESULTS: One hundred and seventeen labs from 30 countries registered and 91 returned results. Sanger sequencing and a commercial kit were the main methodologies used. The standard of genotyping was suboptimal, with a significant number of genotyping errors made. Only 72 out of 91 (72%) participants passed the EQA. False-negative and -positive results were the main sources of error. The quality of reports submitted was acceptable; most were clear, concise and easy to read. However, some participants reported the genotyping result in the absence of any interpretation and many obscured the interpretation required for clinical care. CONCLUSIONS: Even in clinical laboratories, the technical performance of genotyping in EGFR mutation testing for NSCLC can be improved, evident from a high level of diagnostic errors. Robust EQA can contribute to global optimisation of EGFR testing for NSCLC patients.

Quality of diagnostic mutation analyses for phenylketonuria.

DNA sequence analyses have become a major component in the diagnostic work-up of patients; however, limited consideration appears to be given to the possibility that reported results may in fact be wrong. Over the last four years we have carried out an External Quality Assessment scheme for mutation analysis in phenylketonuria. Each year, three DNA samples with previously characterized genotypes were mailed to participating laboratories. Indications for testing were either confirmation of diagnosis and prediction of disease severity, or carrier analysis. Each year there were several laboratories that failed to identify mutations because of methodological limitations. Of the participating laboratories that used comprehensive mutation detection methods, each year there was at least one that missed at least one mutation. Indeed, in the 2007 scheme almost 8% of reports from laboratories that used comprehensive mutation detection methods such as sequencing of all exons of the PAH gene contained incorrect genotypes. There were also serious deficiencies in the interpretation of genotype data: in the 2007 scheme, 6 out of 10 laboratories that obtained full genotyping marks for interpretation incurred a reduction of marks because information on the expected phenotype was missing or wrong. Several laboratories failed to appreciate the clinical relevance of a mutation associated with mild hyperphenylalaninaemia, which does not require treatment, and some discussed the option of prenatal diagnosis in the respective case. In conclusion, mutation analyses may be prone to errors and this demands careful interpretation of results in relation to clinical and biochemical findings.