The impact of idiopathic pulmonary fibrosis on health state utility values: evidence from Australia.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a progressive and universally fatal lung disease, characterised by increasing fibrosis of the lung parenchyma. In this study, we aimed to quantify the health state utility values (HSUVs) for Australians with IPF and to identify the factors affecting these HSUVs. METHODS: Participants of the Australian IPF Registry (AIPFR), with data on EuroQoL five dimension-five level (EQ-5D-5L) profiles were included. Pulmonary function tests (PFTs) were used to assess disease severity using three IPF -based classification systems. Stepwise multivariable linear regression models assessed the relationship between HSUVs and important demographic and clinical parameters.Query RESULTS: A total of 155 participants provided data for the analysis of HSUVs. For our base case, HSUVs ranged from - 0.57 to 1.00. Mean HSUVs for all participants was 0.65 (95% CI 0.61-0.70). In general, HSUVs decreased with increasing disease severity under all disease severity classification systems. Multivariable linear regression demonstrated a negative association between HSUVs, disease severity and having more than 2 comorbidities. CONCLUSIONS: Our study has shown that EQ-5D-5L has exhibited discriminatory sensitivity for the study population. We have demonstrated that disease severity and having more than two comorbidities was associated with lower HSUVs in Australians with IPF. Our findings support early diagnosis and appropriate evidence-based treatment to slow or prevent IPF progression; and identification and treatment of associated comorbidities to potentially improve health-related quality of life in people with IPF.

The economic burden of idiopathic pulmonary fibrosis in Australia: a cost of illness study.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a type of interstitial lung disease found mostly in elderly persons, characterized by a high symptom burden and frequent encounters with health services. This study aimed to quantify the economic burden of IPF in Australia with a focus on resource utilization and associated direct costs. METHODS: Participants were recruited from the Australian IPF Registry (AIPFR) between August 2018 and December 2019. Data on resource utilization and costs were collected via cost diaries and linked administrative data. Clinical data were collected from the AIPFR. A "bottom up" costing methodology was utilized, and the costing was performed from a partial societal perspective focusing primarily on direct medical and non-medical costs. Costs were standardized to 2021 Australian dollars ($). RESULTS: The average annual total direct costs per person with IPF was $31,655 (95% confidence interval (95% CI): $27,723-$35,757). Extrapolating costs based on prevalence estimates, the total annual costs in Australia are projected to be $299 million (95% CI: $262 million-$338 million). Costs were mainly driven by antifibrotic medication, hospital admissions and medications for comorbidities. Disease severity, comorbidities and antifibrotic medication all had varying impacts on resource utilization and costs. CONCLUSION: This cost-of-illness study provides the first comprehensive assessment of IPF-related direct costs in Australia, identifies the key cost drivers and provides a framework for future health economic analyses. Additionally, it provided insight into the major cost drivers which include antifibrotic medication, hospital admissions and medications related to comorbidities. Our findings emphasize the importance of the appropriate management of comorbidities in the care of people with IPF as this was one of the main reasons for hospitalizations.

Quantification in the analysis of polyethylene glycols and their monomethyl ethers by liquid adsorption chromatography with different detectors.

It is shown that the molar mass distribution of polyethylene glycols (PEGs) and their monomethyl ethers can be determined by liquid adsorption chromatography (LAC) on reversed phases using isocratic or gradient elution. In gradient LAC, the evaporative light scattering detector (ELSD) has to be used, which is, however, problematic with respect to quantification. The response factors of the individual oligomers depend strongly on the operating conditions, molar mass, and sample size. These problems do not arise with density and refractive index detection, which can, however, only be applied with isocratic elution. A comparison of the results obtained with these three detectors showed that calibration of the ELSD has to be performed very carefully.

Separation of all oligomers in polyethylene glycols and their monomethyl ethers by one-dimensional liquid chromatography.

Different polymer homologous series having the same repeat unit, but different end groups, can be separated by one-dimensional LAC according to the number of repeat units and functionality, if a favorable combination of the interaction parameters of the repeat unit and the end groups can be found. As an example, polyethylene glycol (PEG) can be determined in PEG monomethyl ethers. The molar mass distribution of the minor component in such samples can be determined even at concentrations of a few percent.

Characterization of PEG in monomethyl ethers of PEG by 2-D LC.

PEGs present in samples of the corresponding monomethyl ethers are analyzed by 2-D LC with LC at critical conditions as the first and liquid adsorption chromatography as the second dimension. The fractions from the first dimension are transferred to the second one by heart-cutting using a ten-port valve. The efficiency of the separation is dramatically improved by adding water to the eluate from the first dimension before the switching valve in order to have a weaker eluent in the fraction than that of the second dimension. By this procedure, the fractions are focussed and reconcentrated. The molar mass distribution of the PEG fraction can be determined with good accuracy even at very low amounts of PEG in the PEG-monomethyl ethers (down to 0.5%).

Liquid chromatography under critical conditions: practical applications in the analysis of amphiphilic polymers.

Liquid chromatography under critical conditions (LCCC) allows the separation of block copolymers from the corresponding homopolymers as well as the separation of homopolymers according to their functionality. At the transition of exclusion and adsorption mode, the polymer chain becomes "chromatographically invisible," and thus a separation according to other structural units can be achieved. In the case of block copolymers this situation can be utilized to detect and determine unwanted homopolymers. At critical conditions for the repeat unit, the other block may be eluted in the exclusion or the adsorption regime. In the first case, the block copolymer is eluted before the homopolymer, and its molar mass can be determined as in size-exclusion chromatography. In the second case, it is eluted later than the homopolymer, and the separation of the individual oligomers can be achieved. Advantages and limitations of different approaches in LCCC are discussed.

Characterization of poly(ethylene glycol)-b-poly(epsilon-caprolactone) by two-dimensional liquid chromatography.

Block copolymers of ethylene oxide and epsilon-caprolactone were synthesized by microwave-assisted polymerization of epsilon-caprolactone with polyethylene glycol monomethyl ethers as initiator. The samples thus obtained were characterized by two-dimensional liquid chromatography with liquid chromatography at critical conditions as the first and liquid exclusion adsorption chromatography as the second dimension. A full baseline separation of all oligomers could be achieved in both dimensions.

A data base for polymer chromatography: temperature dependence of interaction parameters in liquid adsorption chromatography.

The temperature dependence of retention behaviour of polyethylene glycol (PEG) and its mono- and dimethyl ethers was studied on various RP columns in different mobile phases. The accessible volumes and the interaction parameters were determined from slope and intercept in a plot of the elution volumes of the oligomers of a polymer homologous series as a function of the difference of the elution volumes of consecutive oligomers. A quite different dependence of the interaction parameters was observed in the different mobile phases. While in methanol-water the interaction parameter decreases with increasing temperature, the opposite effect is observed in acetonitrile (ACN)-water. In acetone-water, the temperature dependence is almost negligible.

Separation of telechelic oligomers according to architecture by liquid chromatography.

Telechelic oligomers based on diethylene glycol or lower polyethylene glycols and caprolactone or butene oxide can be separated according to their architecture by means of liquid chromatography under adsorption conditions for the hydrophobic block and critical or exclusion conditions for PEG. This behavior, which is predicted by the theory, can be verified by the experiment for block copolymers of ethylene oxide with ɛ-caprolactone and butene oxide. The individual peaks were identified by matrix-assisted time-of-flight mass spectrometry (MALDI-TOF-MS) of fractions obtained by semipreparative liquid chromatography at critical conditions of center block (PEG) and adsorption conditions for outer blocks (PCL and PBO).