Christoph Ahlgrim

Are 10 min of seating enough to guarantee stable haemoglobin and haematocrit readings for the athlete's biological passport?

Haemoglobin (Hb) and haematocrit (Hct) are measured as indirect markers of doping in athletes. We studied the effect of posture on these parameters in a typical antidoping setting. Venous blood samples were obtained from nine endurance athletes (six males, three females) and nine control subjects (six males, three females) immediately and after 5, 10, 15, 20 and 30 min after having adopted a seated position from normal daily activity. Hb (CV 0.72%) and Hct (CV 0.87%) were determined using an automated cell counter, plasma volume changes were calculated. Differences between the time points, gender and groups were calculated using a mixed‐model procedure. Significant changes were observed in the first 10 min after sitting down but no further changes were noted between 10 and 30 min. Mean directional change for Hb and Hct between 0 min and the average of the period from 10 to 30 min was −2.4% (−0.35 g/dl) for Hb and −2.7% (−1.2%) for Hct. Plasma volume increased accordingly. Neither group nor gender had significant effects. Under typical conditions encountered during blood testing in doping control, a period of 10 min in a seated position is sufficient for the vascular volumes to re‐equilibrate and to adapt to the new posture.

Comparison of molecular and extract-based allergy diagnostics with multiplex and singleplex analysis.

BackgroundImmunoCAP ISAC 112, is a commercially available molecular allergy IgE multiplex test. Data on the comparison of this rather novel test with extract-based as well as molecular ImmunoCAP singleplex IgE tests is missing.ObjectiveTo perform a comparison between the ISAC multiplex IgE assay and the ImmunoCAP singleplex test results.MethodsSerum samples of 101 adults with grass pollen allergy were analysed for sIgE to 112 allergenic molecules represented on the ISAC test as well as to common atopy-related extract-based allergy tests with the ImmunoCAP System (house dust mite [d1], cat [e1], dog [e5], cow’s milk [f2], hen’s egg [f1], hazelnut [f17], celery [f85], Alternaria alternate [m6], as well as pollen from birch [t3], hazel [t4], mugwort [w6], and ragweed [w1]). Subsequently statistical analysis was performed with the Spearman rank correlation test and the Clopper-Pearson method in order to compare the ISAC multiplex results with the sIgE singleplex results.ResultsThe positive percent agreements (PPA) and negative percent agreement (NPA) of corresponding allergens between the ISAC sIgE test and the extract-based singleplex ImmunoCAP results at cutoff 0.1 kUA/l varied between 60–100 % for PPA and 78–97 % for NPA.ConclusionWhen taking into account corresponding allergens molecular testing with the ISAC multiplex test correlates well with ImmunoCAP singleplex results.

Hemoglobin mass after 21 days of conventional altitude training at 1816 m.

The underlying mechanisms of altitude training are still a matter of controversial discussion but erythropoietic adaptations with an increase of total haemoglobin mass (tHb) have been shown in several studies, partly depending on an adequate hypoxic dose. The aim of this retrospective study was to investigate if a 3 weeks sojourn at moderate altitude (1816 m) with conventional training sessions (live and train at moderate altitude), especially under real and uncontrolled conditions, results in an increased tHb. tHb was measured in seven male cyclists competing at elite level (German national cycling team, U23 category) prior to the ascent to altitude and immediately after descent to sea-level. The athletes completed a 21 days altitude training camp living at 1816 m and training at 1800-2400 m during the competitive season. No significant difference was found in tHb after the altitude sojourn (prior 927+/-109g vs. 951+/-113g post, 95% CI -13-61g). Additionally, the analysis of red cell volume, plasma volume and blood volume or haemoglobin concentration [Hb] as well as haematocrit (Hct) did not reveal any significant changes. The data supports the theory that an adequate hypoxic dose is required for adaptations of the erythropoietic system with an increase of tHb and a threshold of approximately 2100-2500 m has to be exceeded.

Hemoglobin mass in an elite endurance athlete before, during, and after injury-related immobility.

INTRODUCTION The total hemoglobin (Hb) mass of athletes is of increasing interest in the field of exercise physiology. Hb mass is an important determinant of oxygen uptake (VO2) and thus endurance performance. Furthermore, Hb mass might be useful in the screening for blood doping manipulations in endurance sports. Presently methodical advances allow a rapid and reliable determination of this variable. However, longitudinal data on Hb mass and the potential impact of training and/or immobilization in elite athletes on this variable are scarce. Most published information on this issue has been obtained in microgravity during space flight or used older technology or does not involve highly trained individuals. Therefore, the aim of the present case report was to add data from an elite athlete to illustrate these aspects. This report presents longitudinal Hb mass data of a world class cyclist before, during, and after an injury-related period of immobilization.

Physiology, power output, and racing strategy of a Race Across America finisher.

The Race Across America, a 4800-km nonstop cycle race, is one of the most demanding endurance sports events. We display the racing strategy, power output, HR, hormonal levels, and inflammatory markers of an athlete before and during the race, which he completed in 10 d 23 h.The athlete showed physiological characteristics of a well-trained (nonelite) cyclist (V˙O2peak=63 mL·min·kg, heart volume=11.3 mL·kg). The race was mainly performed at low intensities (mean ± SD: power output=141 ± 76 W, HR=117 ± 14 bpm). During the race, testosterone levels dropped initially by 30-40% and returned to baseline toward the end. Cortisol remained elevated throughout (+75%-90% compared with baseline). Markers of inflammation (C-reactive protein), dehydration, and protein catabolism (albumin) were not affected. The athlete used a race strategy with regular sleeping breaks (total rest=91 h, 45 h of sleep).Contrasting conventional racing strategies for the Race Across America, which aim at minimizing sleep and maximizing ride time, our case demonstrates that by emphasizing regular recovery and sleep, such alternative strategy might lead an equally successful race result.

Ethical considerations for experiments involving elite athletes and "doping".

to the editor: Siebenmann et al. ([5][1]) recently published a double-blind, placebo-controlled study where “cyclists and triathletes” who “participated in endurance competitions on at least national levels,” were submitted to hypoxia (16 h/day) or placebo for 4 wk. Isovolumetric

Therapeutic Depletion of Iron Stores Is Not Associated with a Reduced Hemoglobin Mass in a Hemochromatosis Patient

Introduction: Hereditary hemochromatosis features a dysregulated iron absorption leading to iron overload and organ damage. The regulation of total hemoglobin mass during depletion of iron deposits by therapeutic phlebotomy has not been studied. Case Presentation: The initial ferritin level of the 52-year-old male subject was 1,276 μg/l. Despite successful depletion of iron stores (ferritinmin: 53 μg/l) through phlebotomies, total hemoglobin mass stabilized at the pretherapy level. However, regeneration of total hemoglobin mass was accelerated (up to 10.8 g/day). Conclusion: In this hemochromatosis patient, the total hemoglobin mass was not altered in the long term, but regeneration was accelerated, possibly due to elevated body iron content.

Vergleich molekularer und extraktbasierter IgE-Diagnostik mittels Multiplex- und Singleplex-Test

HintergrundDer ImmunoCAP®-ISAC-112-Allergie-Chip ist ein molekularer IgE-Multiplex-Test. Untersuchungen zum Vergleich mit den Befunden der traditionellen extraktbasierten ImmunoCAP®-Singleplex-IgE-Diagnostik fehlen für die aktuelle Version dieses Tests.ZielDurchführung einer Vergleichsuntersuchung zwischen ImmunoCAP®-ISAC-112- und extraktbasierter ImmunoCAP®-IgE-Testung.MethodenSerumproben von 101 Erwachsenen mit Rhinoconjunctivitis allergica und Graspollenallergie wurden auf IgE gegen 112 Allergene mit dem molekularen Multiplex-Test ISAC sowie auf IgE gegen verbreitete Allergenquellen mittels herkömmlicher extraktbasierter Singleplex-Testung mit dem ImmunoCAP®-System untersucht (Birke [t3], Hasel [t4], Beifuß [w6], Ambrosia [w1], Wiesenlieschgras [g6], Katze [e1], Alternaria alternata [m6], Dermatophagoides pteronyssinus [d1], Haselnuss [f17], Sellerie [f85]). Ein Vergleich der relevanten ISAC-Allergene mit den Ergebnissen der Singleplex-Messungen erfolgte mittels Spearman-Rang-Korrelationstest und weiterführender statistischer Auswertung mit der Clopper-Pearson-Methode.ErgebnisseDer positive Übereinstimmungswert („positive percent agreement“, PPA) und negative Übereinstimmungswert („negative percent agreement“, NPA) der korrespondierenden Allergene des ISAC-IgE-Tests mit der extraktbasierten Immuno-CAP®-sIgE-Diagnostik lagen beim „cut-off“ von 0,1 kUA/l zwischen 60 und 100% für PPA und 78 und 97% für NPA.SchlussfolgerungBei Berücksichtigung der korrespondierenden Allergene korreliert die molekulare IgE-Diagnostik mit dem ISAC-Multiplex-Allergie-Chip gut mit den Ergebnissen der ImmunoCAP®-Singleplex-Testung.

Applying the Optimized CO Rebreathing Method for Measuring Blood Volumes and Hemoglobin Mass in Heart Failure Patients

Introduction: Determination of blood volume, red cell volume, and plasma volume contributes to the understanding of the pathophysiology in heart failure, especially concerning anemia and volume load. The optimized carbon monoxide (CO)-rebreathing method (oCORM) is used to determine these parameters and hemoglobin mass (Hbmass) in exercise physiology. The applicability of oCORM to determine the intravascular volumes and Hbmass in heart failure patients is currently undetermined because assumptions concerning CO kinetics with oCORM rely on healthy subjects with a normal ejection fraction. Therefore, the aim of the present study is to determine the applicability and the systematic error of oCORM arising from a reduced EF when oCORM is used for measurement of intravascular volumes and Hbmass in heart failure patients. Methods: oCORM was performed in 21 patients with heart failure and a reduced ejection fraction (EF) of < 30% (EFsev) and 25 controls (CONT). CO kinetics in capillary blood was studied 3–15 min after commencement of CO rebreathing. Differences in CO kinetics between the groups were assessed using a generalized linear model. The systematic error for determination of Hbmass with oCORM arising from differences in CO kinetics was assessed using the Monte Carlo method. Results: The CO kinetics was significantly different between EFsev and CONT. In both groups, exposure to CO led to a COHb increase to 6.0 ± 1.0% 3 min after CO rebreathing. There were no CO related side effects or any clinical symptoms. Monte Carlo simulation quantifies the systematic error for determination of Hbmass arising from an impaired ejection fraction to be −0.88%. Conclusion: Our results indicate an impaired vascular mixing of CO when EF is severely reduced. When Hbmass is determined using the original oCORM protocol in heart failure patients with a reduced EF, the systematic underestimation of about 1% should be considered. However, the error arising from this impaired vascular mixing appears small and clinically negligible. Furthermore, application of oCORM was safe and not related to any side effects resulting from CO exposure. In conclusion, oCORM can be used for assessing intravascular volumes and Hbmass in patients with a reduced EF.

ORIGINAL ARTICLE: Are 10 min of seating enough to guarantee stable haemoglobin and haematocrit readings for the athlete’s biological passport?: HAEMOGLOBIN, HAEMATOCRIT AND POSTURE

Haemoglobin (Hb) and haematocrit (Hct) are measured as indirect markers of doping in athletes. We studied the effect of posture on these parameters in a typical antidoping setting. Venous blood samples were obtained from nine endurance athletes (six males, three females) and nine control subjects (six males, three females) immediately and after 5, 10, 15, 20 and 30 min after having adopted a seated position from normal daily activity. Hb (CV 0.72%) and Hct (CV 0.87%) were determined using an automated cell counter, plasma volume changes were calculated. Differences between the time points, gender and groups were calculated using a mixed‐model procedure. Significant changes were observed in the first 10 min after sitting down but no further changes were noted between 10 and 30 min. Mean directional change for Hb and Hct between 0 min and the average of the period from 10 to 30 min was −2.4% (−0.35 g/dl) for Hb and −2.7% (−1.2%) for Hct. Plasma volume increased accordingly. Neither group nor gender had significant effects. Under typical conditions encountered during blood testing in doping control, a period of 10 min in a seated position is sufficient for the vascular volumes to re‐equilibrate and to adapt to the new posture.