Deriving reference values and utilities for the QoL-AGHDA in adult GHD

Effects of 18 Months of Growth Hormone Replacement Therapy on Bone Mineral Density in Patients with Adult Growth Hormone Deficiency: A Retrospective Study

OBJECTIVE

The effect of physiological dose growth hormone (GH) replacement therapy on bone mineral density (BMD) in adults with growth hormone deficiency (GHD) is not well defined. We aimed to investigate the effects of 18 months of treatment with recombinant human growth hormone (rhGH) at physiological doses on BMD, body composition (BC), and quality of life (QoL).

METHODS

Sixty-eight patients diagnosed with adult growth hormone deficiency (AGHD) in our hospital were included in this retrospective study. All patients received individualized rhGH replacement to maintain normal serum insulin-like growth factor-1 (IGF-1) levels. BMD and BC measurements were performed by dual energy X-ray absorptiometry (DXA). Excluding those with incomplete follow-up data, we analyzed BMD in 68 patients, as well as BC and QoL in 36 of them.

RESULTS

Compared with the baseline, lumbar spine BMD decreased by 0.008 g/cm² (P=0.006) and increased by 0.011 g/cm² (P=0.045) at month 18, and total hip BMD decreased by 0.005 g/cm² (P=0.008) and did not change significantly from the baseline at month 18. The changes in BMD did not differ by sex, and the increase in BMD was more pronounced in patients with low Z-scores at the baseline (lumbar spine: P=0.005 and total hip: P=0.018). The percentage change from the baseline in BMD was greater for the lumbar spine than for the total hip (P=0.003). Lean body mass (LBM) increased significantly (P=0.012), total body fat ratio (TBF%) decreased significantly (P=0.011), visceral adipose tissue (VAT) decreased significantly (P=0.016), and QoL improved significantly (P < 0.001).

CONCLUSIONS

Within 18 months of treatment, bone resorption manifested first, BMD decreased to a nadir at month 6, and then it increased. The increase in BMD was greater in the lumbar spine than in the hip, and the increase was more pronounced in patients with low BMD. Eighteen months of rhGH replacement therapy significantly improved lumbar spine BMD and improved BC and QoL.

'Mapping' Health State Utility Values from Non-preference-Based Measures: A Systematic Literature Review in Rare Diseases

BACKGROUND

The use of patient-reported outcome measures (PROMs) to monitor the effects of disease and treatment on patient symptomatology and daily life is increasing in rare diseases (RDs) (i.e. those affecting less than one in 2000 people); however, these instruments seldom yield health state utility values (HSUVs) for cost-utility analyses. In such a context, 'mapping' allows HSUVs to be obtained by establishing a statistical relationship between a 'source' (e.g. a disease-specific PROM) and a 'target' preference-based measure [e.g. the EuroQol-5 Dimension (EQ-5D) tool].

OBJECTIVE

This study aimed to systematically review all published studies using 'mapping' to derive HSUVs from non-preference-based measures in RDs, and identify any critical issues related to the main features of RDs, which are characterised by small, heterogeneous, and geographically dispersed patient populations.

METHODS

The following databases were searched during the first half of 2019 without time, study design, or language restrictions: MEDLINE (via PubMed), the School of Health and Related Research Health Utility Database (ScHARRHUD), and the Health Economics Research Centre (HERC) database of mapping studies (version 7.0). The keywords combined terms related to 'mapping' with Orphanet's list of RD indications (e.g. 'acromegaly') in addition to 'rare' and 'orphan'. 'Very rare' diseases (i.e. those with fewer than 1000 cases or families documented in the medical literature) were excluded from the searches. A predefined, pilot-tested extraction template (in Excel^®) was used to collect structured information from the studies.

RESULTS

Two groups of studies were identified in the review. The first group (n = 19) developed novel mapping algorithms in 13 different RDs. As a target measure, the majority used EQ-5D, and the others used the Short-Form Six-Dimension (SF-6D) and 15D; most studies adopted ordinary least squares (OLS) regression. The second group of studies (n = 9) applied previously published algorithms in non-RDs to comparable RDs, mainly in the field of cancer. The critical issues relating to 'mapping' in RDs included the availability of very few studies, the relatively high number of cancer studies, and the absence of research in paediatric RDs. Moreover, the reviewed studies recruited small samples, showed a limited overlap between RD-specific and generic PROMs, and highlighted the presence of cultural and linguistic factors influencing results in multi-country studies. Lastly, the application of existing algorithms developed in non-RDs tended to produce inaccuracies at the bottom of the EQ-5D scale, due to the greater severity of RDs.

CONCLUSIONS

More research is encouraged to develop algorithms for a broader spectrum of RDs (including those affecting young children), improve mapping study quality, test the generalisability of algorithms developed in non-RDs (e.g. HIV) to rare variants or evolutions of the same condition (e.g. AIDS wasting syndrome), and verify the robustness of results when mapped HSUVs are used in cost-utility models.

An Updated Systematic Review of Studies Mapping (or Cross-Walking) Measures of Health-Related Quality of Life to Generic Preference-Based Measures to Generate Utility Values

BACKGROUND

Mapping is an increasingly common method used to predict instrument-specific preference-based health-state utility values (HSUVs) from data obtained from another health-related quality of life (HRQoL) measure. There have been several methodological developments in this area since a previous review up to 2007.

OBJECTIVE

To provide an updated review of all mapping studies that map from HRQoL measures to target generic preference-based measures (EQ-5D measures, SF-6D, HUI measures, QWB, AQoL measures, 15D/16D/17D, CHU-9D) published from January 2007 to October 2018.

DATA SOURCES

A systematic review of English language articles using a variety of approaches: searching electronic and utilities databases, citation searching, targeted journal and website searches.

STUDY SELECTION

Full papers of studies that mapped from one health measure to a target preference-based measure using formal statistical regression techniques.

DATA EXTRACTION

Undertaken by four authors using predefined data fields including measures, data used, econometric models and assessment of predictive ability.

RESULTS

There were 180 papers with 233 mapping functions in total. Mapping functions were generated to obtain EQ-5D-3L/EQ-5D-5L-EQ-5D-Y (n = 147), SF-6D (n = 45), AQoL-4D/AQoL-8D (n = 12), HUI2/HUI3 (n = 13), 15D (n = 8) CHU-9D (n = 4) and QWB-SA (n = 4) HSUVs. A large number of different regression methods were used with ordinary least squares (OLS) still being the most common approach (used ≥ 75% times within each preference-based measure). The majority of studies assessed the predictive ability of the mapping functions using mean absolute or root mean squared errors (n = 192, 82%), but this was lower when considering errors across different categories of severity (n = 92, 39%) and plots of predictions (n = 120, 52%).

CONCLUSIONS

The last 10 years has seen a substantial increase in the number of mapping studies and some evidence of advancement in methods with consideration of models beyond OLS and greater reporting of predictive ability of mapping functions.

Selecting Health States for EQ-5D-3L Valuation Studies: Statistical Considerations Matter

BACKGROUND

For many countries, the three-level EuroQol five-dimensional questionnaire (EQ-5D-3L) value sets have been established to estimate health state utilities. To generate these value sets, researchers first collect values for a subset of preselected health states from a panel representing the general public, and then use a prediction algorithm to generate values for all 243 states. High prevalence of a health state in daily practice has historically been a key criterion in selecting a subset of health states as the observed set. More recently, other criteria have been suggested, especially approaches based on statistical criteria such as randomization and orthogonality.

OBJECTIVES

To evaluate the validity and accuracy of both the earlier and newer criteria, in terms of prediction of values for all the health states and of the values of common health states in particular.

METHODS

We used a pre-existing data set that contained visual analogue scale values from 126 students, each of whom valued all 243 EQ-5D-3L states. Then, we generated a series of designs and subsequently modeled the data with respect to each design. Some of these designs were used in the past; for example, the Measurement and Valuation of Health approach was included. Others were newly generated. The performance of different designs was evaluated in terms of the lowest root mean squared error for all health states taken together, and separately for common and rare states. Classification as common or rare was based on the frequency of the states' occurrence in three patient and population data sets pooled together (N = 5269).

RESULTS

The orthogonal design with 54 health states produced the lowest root mean squared errors. Over-representation of common health states in a design did not improve the estimations for these states. The published designs performed the worst, whereas the random selection designs were good on average. Nevertheless, the performance of the random selection designs showed more variance compared with orthogonal designs, because some of the former designs did not display appropriate balance.

CONCLUSIONS

The published designs gave rise to large estimation errors for the extrapolated EQ-5D-3L health states. The orthogonal design focusing on statistical efficiency showed its superiority. Overall, when weighing up design properties, increased statistical efficiency outweighs an increased error rate, if any, in rare health states.

Design of the Growth hormone deficiency and Efficacy of Treatment (GET) score and non-interventional proof of concept study

BACKGROUND

The adverse effects of growth hormone (GH) deficiency (GHD) in adults (AGHD) on metabolism and health-related quality of life (HRQoL) can be improved with GH substitution. This investigation aimed to design a score summarising the features of GHD and evaluate its ability to measure the effect of GH substitution in AGHD.

METHODS

The Growth hormone deficiency and Efficacy of Treatment (GET) score (0-100 points) assessed (weighting): HRQoL (40%), disease-related days off work (10%), bone mineral density (20%), waist circumference (10%), low-density lipoprotein cholesterol (10%) and body fat mass (10%). A prospective, non-interventional, multicentre proof-of-concept study investigated whether the score could distinguish between untreated and GH-treated patients with AGHD. A 10-point difference in GET score during a 2-year study period was expected based on pre-existing knowledge of the effect of GH substitution in AGHD.

RESULTS

Of 106 patients eligible for analysis, 22 were untreated GHD controls (9 females, mean ± SD age 52 ± 17 years; 13 males, 57 ± 13 years) and 84 were GH-treated (31 females, age 45 ± 13 years, GH dose 0.30 ± 0.16 mg/day; 53 males, age 49 ± 15 years, GH dose 0.25 ± 0.10 mg/day). Follow-up was 706 ± 258 days in females and 653 ± 242 days in males. The GET score differed between the untreated control and treated groups with a least squares mean difference of + 10.01 ± 4.01 (p = 0.0145).

CONCLUSIONS

The GET score appeared to be a suitable integrative instrument to summarise the clinical features of GHD and measure the effects of GH substitution in adults. Exercise capacity and muscle strength/body muscle mass could be included in the GET score.

TRIAL REGISTRATION

NCT number: NCT00934063 . Date of registration: 02 July 2009.

Effectiveness of Short-Term Inpatient Psychotherapy Based on Transactional Analysis With Patients With Personality Disorders: A Matched Control Study Using Propensity Score

Controlled studies on the effectiveness of inpatient psychotherapy with patients with personality disorders (PD) are rare. This study aims to compare 3-month short-term inpatient psychotherapy based on transactional analysis (STIP-TA) with other psychotherapies (OP) up to 36-month follow-up. PD patients treated with STIP-TA were matched with OP patients using the propensity score. The primary outcome measure was general psychiatric symptomatology; secondary outcomes were psychosocial functioning and quality of life. In 67 pairs of patients, both STIP-TA and OP showed large symptomatic and functional improvements. However, STIP-TA patients showed more symptomatic improvement at all time points compared to OP patients. At 36 months, 68% of STIP-TA patients were symptomatically recovered compared to 48% of OP patients. STIP-TA outperformed OP in terms of improvements in general psychiatric symptomatology and quality of life. Superiority of STIP-TA was most pronounced at 12-month follow-up, but remained intact over the course of the 3-year follow-up.

GH deficiency after traumatic brain injury: improvement in quality of life with GH therapy: analysis of the KIMS database

OBJECTIVE

Prevalence of GH deficiency (GHD) caused by traumatic brain injury (TBI) is highly variable. Short-term studies show improvement in quality of life (QoL) during GH replacement (GHR), but long-term data are lacking. The aim of this study was to analyse the clinical characteristics of post-traumatic hypopituitarism and the QoL effects of long-term GHR.

DESIGN/METHODS

Pfizer International Metabolic Database patients with GHD caused by TBI and by non-functioning pituitary adenoma (NFPA) were compared regarding: clinical characteristics at baseline and 1-year of GHR, and QoL response up to 8-years of GHR (QoL-AGHDA total scores and dimensions) in relationship with country-specific norms.

RESULTS

TBI patients compared with NFPA patients were younger, diagnosed with GHD 2.4 years later after primary disease onset (P<0.0001), had a higher incidence of isolated GHD, higher GH peak, a more favourable metabolic profile and worse QoL, were shorter by 0.9 cm (1.8 cm when corrected for age and gender; P=0.004) and received higher GH dose (mean difference: 0.04 mg/day P=0.006). In TBI patients, 1-year improvement in QoL was greater than in NFPA (change in QoL-AGHDA score 5.0 vs 3.5, respectively, P=0.04) and was sustained over 8 years. In TBI patients, socialisation normalised after 1 year of GHR, self-confidence and tenseness after 6 years and no normalisation of tiredness and memory was observed.

CONCLUSION

Compared with NFPA, TBI patients presented biochemically with less severe hypopituitarism and worse QoL scores. GHR achieved clinically relevant, long-term benefit in QoL.