RESUMEN
Acute chest syndrome (ACS) is a severe form of vaso-occlusive crisis, which is a main feature of sickle cell disease (SCD), an inherited hemoglobinopathy. Traditionally, hydroxyurea has been the treatment of choice for SCD to prevent vaso-occlusive crises including ACS. However, hydroxyurea may be contraindicated, for example, in patients wanting to have children. We here present a young male with SCD who wanted to become a father and developed a life-threatening episode of ACS following discontinuation of hydroxyurea and switching to partial exchange blood transfusions. The patient, aged 32 years and originally from Bahrain, had been diagnosed with homozygous SCD, alpha-thalassemia, and glucose-6-phosphate dehydrogenase deficiency as a child. He had an episode of ACS with moderate severity in 2008, after which he started using hydroxyurea. From 2008 until the present, he did not experience any episodes of ACS. About six months before the present episode, he stopped using hydroxyurea and switched to partial exchange transfusions, aiming to keep hemoglobin S (HbS) below 30%. The interval between the transfusions was typically about seven to eight weeks. On the evening (day 1) before hospital admission, he developed typical symptoms and signs of vaso-occlusive crisis, and during the first day in the hospital (HbS about 55%), his pulmonary function deteriorated, and he also developed cerebral symptoms (somnolence and confusion). On suspicion of ACS, a full blood exchange transfusion was administered on day 3. He then gradually recovered clinically, and his laboratory values also normalized. He was discharged on day 10. Subsequent follow-up visits at the outpatient clinic the following month were unremarkable. Possibly, this severe episode of ACS was triggered by switching from hydroxyurea therapy to partial exchange transfusions with too long intervals between the transfusions. This novel case is a compelling reminder of the possible perils that may accompany the discontinuation of hydroxyurea, the best-documented therapy in SCD.
RESUMEN
BACKGROUND: We previously reported that changes of 6-17 percent in the EORTC QLQ-C30 scores are regarded important by patients with multiple myeloma and thus may be considered as Minimal Important Differences (MIDs). However, patients' internal standard of measurement may have changed over time (response shift, RS). In the present work, we evaluated whether myeloma patients experience RS and if this could affect the MID-estimates. METHODS: Between 2006 and 2008, 239 patients with multiple myeloma completed the EORTC QLQ-C30 at baseline (T1) and after three months (T2). At T2, patients were asked if they had noticed any change in the domains pain, fatigue, physical function and global quality of life. They were also asked to give a retrospective judgment of their baseline values on all the four domains. RESULTS: We found clear evidence of RS in myeloma patients. However, there were differences in both magnitude and direction between patients who stated that they improved and those who deteriorated. Deteriorating patients retrospectively reported better health-related quality of life at T1 for the domains pain, fatigue and physical function. In these patients, MIDs adjusted for RS were observed to increase up to 12 percentage points. In contrast, for patients stating that they improved, we only found evidence of statistically significant RS in the domain global quality of life. CONCLUSIONS: MIDs estimated from pre-test/post-test data appeared to be robust against RS in patients reporting improvement over 3-months. This could indicate that RS has a minimal impact on the results in patients who respond to treatment, and that RS may not have an important impact on interpretation of changes reported in clinical trials where an improvement occurs.Although the effect sizes of the RSs were small, RS in deteriorating patients may have an important impact on the interpretation of changes reported in clinical trials.
Asunto(s)
Indicadores de Salud , Mieloma Múltiple/psicología , Calidad de Vida , Encuestas y Cuestionarios , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Humanos , Entrevistas como Asunto , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Mieloma Múltiple/terapia , Noruega , Psicometría , Estándares de Referencia , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
OBJECTIVE: To determine the clinical significance of changes in quality-of-life scores in patients with multiple myeloma (MM), we have estimated the minimal important difference (MID) for the health-related quality-of-life instrument, the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30. The MID is the smallest change in a quality-of-life score considered important to patients. METHODS: Between 2006 and 2008, 239 patients with MM completed the EORTC QLQ-C30 at inclusion (T1) and after 3 months (T2). At T2, a structured quality-of-life interview was also performed. MIDs were calculated by using mean score changes (T2-T1) for patients who in the interview stated they had improved, deteriorated or were unchanged. MIDs were also estimated by the receiver-operating characteristic (ROC) curve method as well as by calculation effect sizes using standard deviations of baseline scores. RESULTS: MIDs varied slightly depending on the method used. Patients stating in the interview that they had 'improved' or 'deteriorated' had a corresponding change in EORTC QLQ-C30 score ranging from 6 to15 (improvement) and from 9 to17 (deterioration) (scale range 0-100). The ROC analysis indicated that changes in score from 7 to17 represent clinically important changes to patients. The effect size method suggested 5-6 to be a small and 11-15 to be a medium change. CONCLUSION: Calculation of MIDs as mean score changes or by ROC analysis suggested that a change in the EORTC QLQ-C30 score in the range of approximately 6-17 is considered important by patients with MM. These MIDs are closer to a medium effect size than to a small effect size. Our findings imply that mean score changes smaller than 6 are unlikely to be important to the patients, even if these changes are statistically significant.