Ordering blood tests for patients with unexplained fatigue in general practice: what does it yield? Results of the VAMPIRE trial

Abstract

Unexplained fatigue is frequently encountered in general practice. Because of the low prior probability of underlying somatic pathology, the positive predictive value of abnormal (blood) test results is limited in such patients. AimThe study objectives were to investigate the relationship between established diagnoses and the occurrence of abnormal blood test results among patients with unexplained fatigue; to survey the effects of the postponement of test ordering on this relationship; and to explore consultation-related determinants of abnormal test results. Design of studyCluster randomised trial. SettingGeneral practices of 91 GPs in the Netherlands. MethodGPs were randomised to immediate or postponed bloodtest ordering. Patients with new unexplained fatigue were included. Limited and expanded sets of blood tests were ordered either immediately or after 4 weeks. Diagnoses during the 1-year follow-up period were extracted from medical records. Two-by-two tables were generated. To establish independent determinants of abnormal test results, a multivariate logistic regression model was used. ResultsData of 325 patients were analysed (71% women; mean age 41 years). Eight per cent of patients had a somatic illness that was detectable by blood-test ordering. The number of false-positive test results increased in particular in the expanded test set. Patients rarely reconsulted after 4 weeks. Test postponement did not affect the distribution of patients over the two-by-two tables. No independent consultation-related determinants of abnormal test results were found. ConclusionResults support restricting the number of tests ordered because of the increased risk of false-positive test results from expanded test sets. Although the number of reconsulting patients was small, the data do not refute the advice to postpone blood-test ordering for medical reasons in patients with unexplained fatigue in general practice.

Agotamiento profesional (burnout): concepciones e implicaciones para la salud pública

“…Presentados estos puntos de análisis, y a pesar de su denominación como síndrome (conjunto de signos y síntomas), el agotamiento profesional debe asumirse como una enfermedad, por las siguientes razones: a) existen condiciones del entorno, del trabajo y del sujeto mismo (por ejemplo, la edad, el sexo) que pueden tener una incidencia negativa en las personas; b) es posible caracterizarlo a partir de las percepciones del individuo y las observaciones metódicas de los profesionales de la salud, particularmente de los médicos, e incluso, es posible determinar niveles de gravedad (25); c) sus manifestaciones pueden detectarse con instrumentos especialmente diseñados y, además, clasificarse y separarse de otras condiciones como el "sufrimiento mental" (85), el "estrés" (86), la "fatiga por compasión" (81) o los síndromes "de cansancio a toda hora" (Constant Fatigue Syndrome) (82-84) y de "fatiga crónica" (87), no relacionadas con el cáncer o la sarcopenia; d) afecta uno o más sistemas orgánicos del ser humano, con el agravante de comprometer no solo la salud mental (32); e) puede curarse con medios no farmacológicos o con medicamentos (88,89), lo que no previene las recaídas; f) su presencia y las condiciones que lo propician pueden ayudar al médico a ofrecer un pronóstico, aunque este se base en la frecuencia de ocurrencia y de recaída de la enfermedad; g) ha sido estudiado en un entorno multidisciplinario o interdisciplinario que incluye disciplinas médicas como la psiquiatría o la epidemiología clínica, y ciencias sociales como la psicología, así como las ciencias matemáticas y la bioestadística (90,91); h) genera desequilibrio e impotencia en los sujetos, y pone en peligro el logro de sus ideales o su perfeccionamiento;…”

Tired all the time: can new research on fatigue help clinicians?

“…8 In this month's issue Koch and colleagues report the results of the VAMPIRE study, a Dutch-based study designed to investigate the value of blood-test ordering for a range of unexplained complaints, including fatigue. 9 By examining medical records they found that only 8% of patients presenting with fatigue had a blood-test detectable somatic illness diagnosed over a 1-year follow-up period. The vast majority of the disorders diagnosed could be detected from a very limited set of simple blood tests (haemoglobin, erythrocyte sedimentation rate, glucose, and thyroid stimulating hormone).…”

First do no harm: data gathering and interpretation

“…Among patients presenting with fatigue, the odds (probability) of a range of blood tests done on any one patient giving a false positive are 1:1 (56%) and of giving a true positive are 1:12 (8%). 8 Among patients having blood tests done to reassure them, the odds (probability) of any one patient having an abnormal result are 1:1 (56%) and a markedly abnormal result are 1:8 (12%).…”