The effect of long-term untreated growth hormone deficiency (GHD) and 9 years of GH replacement on the quality of life (QoL) of GH-deficient adults

Le questionnaire de qualité de vie QLS-H© : validation de la version française chez les patients avec déficit en hormone de croissance et acquisition des valeurs de référence dans la population générale

The QLS-H(c) (Questions on Life Satisfaction- Hypopituitarism) is new a quality of life (QoL) self-administered questionnaire addressing the complaints of adult patients with growth hormone deficiency. The French version of the QLS-H(c) (16 items) has been psychometrically evaluated during a randomized, open label study comparing two strategies of growth hormone (GH) replacement therapy. Seventy-three patients were included and received an 8-month GH replacement therapy. QoL was explored at baseline, 4 and 8 months using the QLS-H(c) questionnaire and the Nottingham Health Profile (NHP) reference scale. Acceptance of the QLS-H(c) was excellent as 92% of the questionnaires were suitable for analysis. All the items demonstrated good selectivity. The homogeneity of the questionnaire was confirmed (Cronbach's alpha, 0.87). The external validity construct was assessed and confirmed using the NHP scores. Sensitivity to change was confirmed. Following an 8-month replacement therapy, the perception of the QoL assessed with the QLS-H(c) questionnaire was significantly improved, irrespective to the treatment strategy. Finally, redundant items of the questionnaire were removed. As a result, the final version of the QLS-H(c) contained 9 items. In a parallel study, reference data of the QLS-H(c) (9 items) were collected from a representative sample of 989 subjects from the French population. With these reference ranges, algorithms to calculate Z scores adjusted for age and gender were developed as a measure for the deviation of patients' scores from those of the general population, and also to evaluate changes along time. In summary, the French version of the quality of life QLS-H(c) questionnaire is a relevant, validated investigational tool for the evaluation and follow-up of an adult patient with growth hormone deficiency.

Occurrence of Pituitary Dysfunction following Traumatic Brain Injury

Traumatic brain injury (TBI) may be associated with impairment of pituitary hormone secretion, which may contribute to long-term physical, cognitive, and psychological disability. We studied the occurrence and risk factors of pituitary dysfunction, including growth hormone deficiency (GHD) in 50 patients (mean age 37.6 +/- 2.4 years; 40 males, age 20-60 years; 10 females, age 23-87 years) with TBI over 5 years. Cranial or facial fractures were documented in 12 patients, and neurosurgery was performed in 14. According to the Glasgow Coma Scale (GCS), 16 patients had suffered from mild, 7 moderate, and 27 severe TBI. Glasgow Outcome Scale (GOS) indicated severe disability in 5, moderate disability in 11, and good recovery in 34 cases. Basal pituitary hormone evaluation, performed once at times variable from 12 to 64 months after TBI, showed hypogonadotrophic hypogonadism in 7 (14%), central hypothyroidism in 5 (10%), low prolactin (PRL) levels in 4 (8%), and high PRL levels in 4 (8%) cases. All subjects had normal corticotrophic and posterior pituitary function. Seven patients showed low insulin-like growth factor-I (IGF-I) levels for age and sex. Results of GHRH plus arginine testing indicated partial GHD in 10 (20%) and severe GHD in 4 (8%) cases. Patients with GHD were older (p <0.05) than patients with normal GH secretion. Magnetic resonance imaging demonstrated pituitary abnormalities in 2 patients; altogether pituitary dysfunction was observed in 27 (54%) patients. Six patients (12%) showed a combination of multiple abnormalities. Occurrence of pituitary dysfunction was 37.5%, 57.1%, and 59.3% in the patients with mild, moderate, and severe TBI, respectively. GCS scores were significantly (p <0.02) lower in patients with pituitary dysfunction compared to those with normal pituitary function (8.3 +/- 0.5 vs. 10.2 +/- 0.6). No relationship was detected between pituitary dysfunction and years since TBI, type of injury, and outcome from TBI. In conclusion, subjects with a history of TBI frequently develop pituitary dysfunction, especially GHD. Therefore, evaluation of pituitary hormone secretion, including GH, should be included in the long-term follow-up of all TBI patients so that adequate hormone replacement therapy may be administered.

Bridging Regional and Global Perspectives

In recent years, medical practice has evolved towards greater reliance on evidence-based medicine. Societies and reimbursement agencies often publish recommendations for treatment based on literature review and trial data. Despite this, growth hormone (GH) replacement therapy in adults varies substantially from region to region. The reasons for this include differing beliefs in quality of life benefits, the cost-effectiveness of GH and the role of GH in reducing cardiovascular mortality. Reimbursement varies from almost complete take-up in Sweden and Germany, to strict guidelines in the UK, while in some countries GH is not reimbursable for adults with GH deficiency, leaving patients open to the short- and long-term consequences of the condition. Clearly, there is a need for further evidence regarding the overall value of GH replacement. Randomized, controlled trials are the foundation of evidence-based medicine, but long-term treatment is difficult to assess in such trials. Thus, there is an important role for large-scale registries in gathering evidence. For example, the MEGHA (Metabolic Endocrinology and Growth Hormone Assessment) database provides participants with a sub- studies function, allowing them to create and design collective, observational studies to investigate areas of GH medicine that are of particular interest or concern to them and their patients.

Growth hormone therapy and quality of life in adults and children

A fundamental goal of growth hormone (GH) treatment for both adults and children is improvement in quality of life (QOL). Assessments of the therapeutic role of GH depend on its effectiveness in meeting this and other goals (including improved metabolic status in adults and improved growth in children) in relation to economic parameters. However, there are difficulties in interpreting data on GH treatment and QOL. These include controversy about appropriate definitions and measures for assessing QOL, disease adaptation, comorbid conditions, and potential patient selection bias. In GH-deficient adults who have completed linear growth, there is considerable evidence that GH exerts effects on body composition, serum lipids, and bone and mineral density. Several controlled trials have also examined the effect of GH treatment on QOL in GH-deficient adults. They generally indicate improvement in QOL with GH treatment, although there are inconsistencies in the data. Caveats include differing outcome measures and instruments, instruments that are not disease specific, variation in characteristics of patient samples and treatment protocols, evidence of a placebo effect, and some inconsistency among results. Open-label trials in adults also suggest improvement in QOL with GH treatment, although interpretation is limited by potential placebo effects and patient self-selection. Studies in children have generally addressed psychological status, and relatively few specifically focus on QOL. In children with classical GH deficiency, it is intuitive that GH treatment will improve QOL, although hard data are lacking. In children with idiopathic short stature, evidence for improved QOL as a result of GH treatment is not well developed. Translating changes in QOL, together with physiological and metabolic benefits, into economic cost-benefit or cost-effectiveness analyses are needed. In doing so, it will be important to consider subgroups of patients who may derive differential benefit from GH treatment. These analyses are central to the development of a framework for research, decision making, and policy for GH treatment.

Assessment of quality of life in adults receiving long-term growth hormone replacement compared to control subjects

OBJECTIVE

There are few studies of quality of life (QOL) in adults with growth hormone deficiency (GHD) compared to matched control populations without GHD. These have shown impairments in a variety of QOL measures, which improve but do not normalize after short-term replacement with GH. There is little information on QOL in long-term treated GHD patients compared with controls without GHD.

PATIENTS AND METHODS

A total of 120 adults with GHD who had received GH replacement for at least 1 year were identified from the neuroendocrine clinic. Patients were asked to complete eight QOL questionnaires and an Energy Visual Analogue Scale (VAS). Results were compared with 83 control subjects without GHD from the local population who agreed to complete seven of the QOL questionnaires (excluding Disease Impact scale) and the energy VAS. The eight questionnaires were a combination of generic and disease-specific questionnaires used to assess health related QOL, namely: Short Form-36 (SF-36), Nottingham Health Profile (NHP), Disease Impact, Life Fulfilment and Satisfaction scales, Mental Fatigue Questionnaire (MFQ) and Self Esteem scale, Hospital Anxiety Depression (HAD) scale and QOL-AGHDA (assessment of GHD in adults).

RESULTS

Eighty-nine patients returned questionnaires and 85 (71%) had complete data for analysis. The mean (SD) duration of GH replacement was 36.0 +/- 26.4 (range 13-159) months. Mean age was 43.9 +/- 15.8 years (37 males) in treated GHD patients compared to a mean age 41.7 +/- 10.5 years (32 males) in the controls. Mean IGF-1 levels were 22.5 +/- 13.6 nmol/l in the GHD patients and the mean dose of GH replacement was 1.2 +/- 0.4 IU daily. Analysis of the QOL questionnaires from the GH treated patients revealed highly significant impairments in all measures (most P </= 0.0001, except life fulfilment-material, P = 0.33) compared to the control population.

CONCLUSIONS

This large population with treated GH deficiency have significant impairments in multiple aspects of QOL despite replacement with GH and other pituitary hormones for at least 1 year (mean 3 years). It is likely therefore that other factors in addition to GH deficiency must influence QOL in these patients. Further strategies to improve QOL in these individuals should therefore be considered, e.g. psychological support and treatments and physical treatments (such as exercise programmes).