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1.
Hum Reprod ; 39(3): 586-594, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38177084

RESUMEN

STUDY QUESTION: Do ongoing pregnancy rates (OPRs) differ in predicted hyperresponders undergoing ART after IVM of oocytes compared with conventional ovarian stimulation (OS) for IVF/ICSI? SUMMARY ANSWER: One cycle of IVM is non-inferior to one cycle of OS in women with serum anti-Müllerian hormone (AMH) levels ≥10 ng/ml. WHAT IS KNOWN ALREADY: Women with high antral follicle count and elevated serum AMH levels, indicating an increased functional ovarian reserve, are prone to hyperresponse during ART treatment. To avoid iatrogenic complications of OS, IVM has been proposed as a mild-approach alternative treatment in predicted hyperresponders, including women with polycystic ovary syndrome (PCOS) who are eligible for ART. To date, inferior pregnancy rates from IVM compared to OS have hampered the uptake of IVM by ART clinics. However, it is unclear whether the efficiency gap between IVM and OS may differ depending on the extent of AMH elevation. STUDY DESIGN, SIZE, DURATION: This study is a retrospective cohort analysis of clinical and laboratory data from the first completed highly purified hMG (HP-hMG) primed, non-hCG-triggered IVM or OS (FSH or HP-hMG stimulation in a GnRH antagonist protocol) cycle with ICSI in predicted hyperresponders ≤36 years of age at a tertiary referral university hospital. A total of 1707 cycles were included between January 2016 and June 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Predicted hyperresponse was defined as a serum AMH level ≥3.25 ng/ml (Elecsys® AMH, Roche Diagnostics). The primary outcome was cumulative ongoing pregnancy rate assessed 10-11 weeks after embryo transfer (ET). The predefined non-inferiority limit was -10.0%. The analysis was adjusted for AMH strata. Time-to-pregnancy, defined as the number of ET cycles until ongoing pregnancy was achieved, was a secondary outcome. Statistical analysis was performed using a multivariable regression model controlling for potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Data from 463 IVM cycles were compared with those from 1244 OS cycles. Women in the IVM group more often had a diagnosis of Rotterdam PCOS (434/463, 93.7%) compared to those undergoing OS (522/1193, 43.8%), were significantly younger (29.5 years versus 30.5 years, P ≤ 0.001), had a higher BMI (25.7 kg/m2 versus 25.1 kg/m2, P ≤ 0.01) and higher AMH (11.6 ng/ml versus 5.3 ng/ml, P ≤ 0.001). Although IVM cycles yielded more cumulus-oocyte complexes (COCs) (24.5 versus 15.0 COC, P ≤ 0.001), both groups had similar numbers of mature oocytes (metaphase II (MII)) (11.9 MII versus 10.6 MII, P = 0.9). In the entire cohort, non-adjusted cumulative OPR from IVM was significantly lower (198/463, 42.8%) compared to OS (794/1244, 63.8%), P ≤ 0.001. When analysing OPR across different serum AMH strata, cumulative OPR in both groups converged with increasing serum AMH, and OPR from IVM was non-inferior compared to OS from serum AMH levels >10 ng/ml onwards (113/221, 51.1% (IVM); 29/48, 60.4% (OS)). The number of ETs needed to reach an ongoing pregnancy was comparable in both the IVM and the OS group (1.6 versus 1.5 ET's, P = 0.44). Multivariable regression analysis adjusting for ART type, age, BMI, oocyte number, and PCOS phenotype showed that the number of COCs was the only parameter associated with OPR in predicted hyperresponders with a serum AMH >10 ng/ml. LIMITATIONS, REASONS FOR CAUTION: These data should be interpreted with caution as the retrospective nature of the study holds the possibility of unmeasured confounding factors. WIDER IMPLICATIONS OF THE FINDINGS: Among subfertile women who are eligible for ART, IVM, and OS resulted in comparable reproductive outcomes in a subset of women with a serum AMH ≥10 ng/ml. These findings should be corroborated by a randomised controlled trial (RCT) comparing both treatments in selected patients with elevated AMH. STUDY FUNDING/COMPETING INTEREST(S): There was no external funding for this study. P.D. has been consultant to Merck Healthcare KGaA (Darmstadt, Germany) from April 2021 till June 2023 and is a Merck employee (Medical Director, Global Medical Affairs Fertility) with Merck Healthcare KGAaA (Darmstadt, Germany) since July 2023. He declares honoraria for lecturing from Merck KGaA, MSD, Organon, and Ferring. The remaining authors declared no conflict of interest pertaining to this study. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Técnicas de Maduración In Vitro de los Oocitos , Síndrome del Ovario Poliquístico , Femenino , Humanos , Embarazo , Hormona Antimülleriana , Oocitos , Síndrome del Ovario Poliquístico/terapia , Inyecciones de Esperma Intracitoplasmáticas , Estudios Retrospectivos , Adulto
2.
Transfusion ; 64(3): 554-559, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38205646

RESUMEN

BACKGROUND: Hematopoietic stem cell transplant (HSCT) is currently the only widely available curative option for patients with sickle cell disease (SCD). Alloimmunization in this population is frequent and can complicate transfusion management during the HSCT period. The case of a pediatric patient with severe SCD clinical phenotype, multiple alloantibodies (9), and hyperhemolysis syndrome who underwent haploidentical HSCT is described. STUDY DESIGN AND METHODS: The patient was known for an anti-e, despite RHCE*01.01 allele, which predicts a C- c+ E- weak e+ phenotype. Donors matching the patient's extended phenotype were targeted for RHCE genotyping. RESULTS: Donors homozygotes or heterozygotes for RHCE*01.01 were selected for compatibility analyses and ranked based on strength of reactions. Discordance between zygosity and strength of reactions was observed, as the most compatible donors were heterozygotes for RHCE*01.01. In total, the patient received seven RBC units from two different donors during HSCT process without transfusion reaction or development of new alloantibodies. Six months post-HSCT, his hemoglobin level is stable at around 120 g/L and his chimerism is 100%. DISCUSSION: This case highlights the complexity of transfusion management during HSCT of alloimmunized patients with SCD. Collecting sufficient compatible units requires early involvement of transfusion medicine teams and close communication with the local blood provider. Genotyping of donors self-identifying as Black is useful for identifying compatible blood for those patients but has some limitations. HSCT for heavily alloimmunized patients is feasible and safe with early involvement of transfusion medicine specialists. Further research on the clinical impact of genotypic matching is needed.


Asunto(s)
Anemia de Células Falciformes , Trasplante de Células Madre Hematopoyéticas , Humanos , Niño , Isoanticuerpos , Eritrocitos , Transfusión Sanguínea
3.
Br J Nutr ; 117(3): 403-412, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28215212

RESUMEN

TAG depleted remnants of postprandial chylomicrons are a risk factor for atherosclerosis. Recent studies have demonstrated that in the fasted state, the majority of chylomicrons are small enough for transcytosis to arterial subendothelial space and accelerate atherogenesis. However, the size distribution of chylomicrons in the absorptive state is unclear. This study explored in normolipidaemic subjects the postprandial distribution of the chylomicron marker, apoB-48, in a TAG-rich lipoprotein plasma fraction (Svedberg flotation rate (Sf>400), in partially hydrolysed remnants (Sf 20-400) and in a TAG-deplete fraction (Sf<20), following ingestion of isoenergetic meals with either palm oil (PO), rice bran or coconut oil. Results from this study show that the majority of fasting chylomicrons are within the potentially pro-atherogenic Sf<20 fraction (70-75 %). Following the ingestion of test meals, chylomicronaemia was also principally distributed within the Sf<20 fraction. However, approximately 40 % of subjects demonstrated exaggerated postprandial lipaemia specifically in response to the SFA-rich PO meal, with a transient shift to more buoyant chylomicron fractions. The latter demonstrates that heterogeneity in the magnitude and duration of hyper-remnantaemia is dependent on both the nature of the meal fatty acids ingested and possible metabolic determinants that influence chylomicron metabolism. The study findings reiterate that fasting plasma TAG is a poor indicator of atherogenic chylomicron remnant homoeostasis and emphasises the merits of considering specifically, chylomicron remnant abundance and kinetics in the context of atherogenic risk. Few studies address the latter, despite the majority of life being spent in the postprandial and absorptive state.


Asunto(s)
Apolipoproteína B-48/sangre , Aterosclerosis/etiología , Remanentes de Quilomicrones/sangre , Grasas de la Dieta/administración & dosificación , Metabolismo de los Lípidos/fisiología , Periodo Posprandial , Triglicéridos/sangre , Adulto , Aterosclerosis/sangre , Quilomicrones/sangre , Estudios Cruzados , Grasas de la Dieta/sangre , Ayuno , Femenino , Homeostasis , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/etiología , Masculino , Comidas , Persona de Mediana Edad , Aceite de Palma , Tamaño de la Partícula , Aceites de Plantas/administración & dosificación , Aceites de Plantas/metabolismo , Valores de Referencia , Factores de Riesgo
4.
Metabolites ; 14(1)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38276308

RESUMEN

Recent research has identified a unique population of 'Lean Mass Hyper-Responders' (LMHR) who exhibit increases in LDL cholesterol (LDL-C) in response to carbohydrate-restricted diets to levels ≥ 200 mg/dL, in association with HDL cholesterol ≥ 80 mg/dL and triglycerides ≤ 70 mg/dL. This triad of markers occurs primarily in lean metabolically healthy subjects, with the magnitude of increase in LDL-C inversely associated with body mass index. The lipid energy model has been proposed as one explanation for LMHR phenotype and posits that there is increased export and subsequent turnover of VLDL to LDL particles to meet systemic energy needs in the setting of hepatic glycogen depletion and low body fat. This single subject crossover experiment aimed to test the hypothesis that adding carbohydrates, in the form of Oreo cookies, to an LMHR subject on a ketogenic diet would reduce LDL-C levels by a similar, or greater, magnitude than high-intensity statin therapy. The study was designed as follows: after a 2-week run-in period on a standardized ketogenic diet, study arm 1 consisted of supplementation with 12 regular Oreo cookies, providing 100 g/d of additional carbohydrates for 16 days. Throughout this arm, ketosis was monitored and maintained at levels similar to the subject's standard ketogenic diet using supplemental exogenous d-ß-hydroxybutyrate supplementation four times daily. Following the discontinuation of Oreo supplementation, the subject maintained a stable ketogenic diet for 3 months and documented a return to baseline weight and hypercholesterolemic status. During study arm 2, the subject received rosuvastatin 20 mg daily for 6 weeks. Lipid panels were drawn water-only fasted and weekly throughout the study. Baseline LDL-C was 384 mg/dL and reduced to 111 mg/dL (71% reduction) after Oreo supplementation. Following the washout period, LDL-C returned to 421 mg/dL, and was reduced to a nadir of 284 mg/dL with 20 mg rosuvastatin therapy (32.5% reduction). In conclusion, in this case study experiment, short-term Oreo supplementation lowered LDL-C more than 6 weeks of high-intensity statin therapy in an LMHR subject on a ketogenic diet. This dramatic metabolic demonstration, consistent with the lipid energy model, should provoke further research and not be seen as health advice.

5.
Clin Case Rep ; 12(2): e8485, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38323135

RESUMEN

Key Clinical Message: Although the lean mass hyper-responder (LMHR) phenotype is well known, its diagnosis is impeded by the influence of fat type and intake on the lipid profile. Accordingly, a detailed assessment is warranted if LMHR is suspected. Abstract: A 47-year-old man with suspected familial hypercholesterolemia presented with elevated triglyceride and low-density lipoprotein cholesterol levels. He had adhered to a ketogenic diet and was suspected of a lean mass hyper-responder phenotype; however, his lipid profile did not meet the definition. His lipid profile improved through dietary management without medication.

6.
Front Endocrinol (Lausanne) ; 14: 1326768, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38189051

RESUMEN

Introduction: There is a large heterogeneity in LDL-cholesterol change among individuals adopting ketogenic diets. Interestingly, lean metabolically healthy individuals seem to be particularly susceptible, with an inverse association between body mass index and LDL-cholesterol change. The lipid energy model proposes that, in lean healthy individuals, carbohydrate restriction upregulates systemic lipid trafficking to meet energy demands. To test if anthropometric and energy metabolism markers predict LDL-cholesterol change during carbohydrate restriction. Methods: Ten lean, healthy, premenopausal women who habitually consumed a ketogenic diet for ≥6 months were engaged in a three-phase crossover study consisting of continued nutritional ketosis, suppression of ketosis with carbohydrate reintroduction, and return to nutritional ketosis. Each phase lasted 21 days. The predictive performance of all available relevant variables was evaluated with the linear mixed-effects models. Results: All body composition metrics, free T3 and total T4, were significantly associated with LDL-cholesterol change. In an interaction model with BMI and free T3, both markers were significant independent and interacting predictors of LDL-cholesterol change. Neither saturated fat, HOMA-IR, leptin, adiponectin, TSH, nor rT3 was associated with LDL-cholesterol changes. Discussion: Among lean, healthy women undergoing carbohydrate restriction, body composition and energy metabolism markers are major drivers of LDL-cholesterol change, not saturated fat, consistent with the lipid energy model.


Asunto(s)
Dieta Cetogénica , Cetosis , Humanos , Femenino , Estudios Cruzados , Glándula Tiroides , Composición Corporal , LDL-Colesterol , Carbohidratos
7.
Curr Dev Nutr ; 6(1): nzab144, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35106434

RESUMEN

BACKGROUND: People commencing a carbohydrate-restricted diet (CRD) experience markedly heterogenous responses in LDL cholesterol, ranging from extreme elevations to reductions. OBJECTIVES: The aim was to elucidate possible sources of heterogeneity in LDL cholesterol response to a CRD and thereby identify individuals who may be at risk for LDL cholesterol elevation. METHODS: Hypothesis-naive analyses were conducted on web survey data from 548 adults consuming a CRD. Univariate and multivariate regression models and regression trees were built to evaluate the interaction between body mass index (BMI) and baseline lipid markers. Data were also collected from a case series of five clinical patients with extremely high LDL cholesterol consuming a CRD. RESULTS: BMI was inversely associated with LDL cholesterol change. Low triglyceride (TG) to HDL cholesterol ratio, a marker of good metabolic health, predicted larger LDL cholesterol increases. A subgroup of respondents with LDL cholesterol ≥200 mg/dL, HDL cholesterol ≥80 mg/dL, and TG ≤70 mg/dL were characterized as "lean mass hyper-responders." Respondents with this phenotype (n = 100) had a lower BMI and, remarkably, similar prior LDL cholesterol versus other respondents. In the case series, moderate reintroduction of carbohydrate produced a marked decrease in LDL cholesterol. CONCLUSIONS: These data suggest that, in contrast to the typical pattern of dyslipidemia, greater LDL cholesterol elevation on a CRD tends to occur in the context of otherwise low cardiometabolic risk.

8.
Front Endocrinol (Lausanne) ; 13: 830325, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35498420

RESUMEN

Emerging evidence suggests that "leanness" and good metabolic health markers may predict larger increases in LDL cholesterol (LDL-C) in response to carbohydrate restriction. Specifically, a recent cohort study demonstrated an inverse association between BMI and LDL-C change among individuals on carbohydrate-restricted diets and identified a subgroup of "Lean Mass Hyper-Responders" (LMHR) who exhibit exceptional increases in LDL-C, in the context of low triglycerides and high HDL-C. We present the case of one subject, LM, who adopted a ketogenic diet for management of ulcerative colitis. He subsequently experienced an increase in LDL-C from 95 to 545 mg/dl, at peak, in association with HDL-C >100 mg/dl and triglycerides ~40 mg/dl, typical of the emergent LMHR phenotype. Assessments of LM's dietary intake, lipid panels, and BMI are consistent with prior data and suggest that the LMHR phenomenon is not dependent on saturated fat intake but inversely associates with BMI changes. Finally, computed tomography angiography conducted on LM after over 2 years of hypercholesterolemia revealed no evidence of calcified or non-calcified plaque.


Asunto(s)
Hipercolesterolemia , Hiperlipidemias , Carbohidratos , LDL-Colesterol , Dieta Baja en Carbohidratos , Humanos , Hipercolesterolemia/etiología , Masculino , Fenotipo , Triglicéridos
9.
Metabolites ; 12(5)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35629964

RESUMEN

When lean people adopt carbohydrate-restricted diets (CRDs), they may develop a lipid profile consisting of elevated LDL-cholesterol (LDL-C) and HDL-cholesterol (HDL-C) with low triglycerides (TGs). The magnitude of this lipid profile correlates with BMI such that those with lower BMI exhibit larger increases in both LDL-C and HDL-C. The inverse association between BMI and LDL-C and HDL-C change on CRD contributed to the discovery of a subset of individuals-termed Lean Mass Hyper-Responders (LMHR)-who, despite normal pre-diet LDL-C, as compared to non-LMHR (mean levels of 148 and 145 mg/dL, respectively), exhibited a pronounced hyperlipidemic response to a CRD, with mean LDL-C and HDL-C levels increasing to 320 and 99 mg/dL, respectively, in the context of mean TG of 47 mg/dL. In some LMHR, LDL-C levels may be in excess of 500 mg/dL, again, with relatively normal pre-diet LDL-C and absent of genetic findings indicative of familial hypercholesterolemia in those who have been tested. The Lipid Energy Model (LEM) attempts to explain this metabolic phenomenon by positing that, with carbohydrate restriction in lean persons, the increased dependence on fat as a metabolic substrate drives increased hepatic secretion and peripheral uptake of TG contained within very low-density lipoproteins (VLDL) by lipoprotein lipase, resulting in marked elevations of LDL-C and HDL-C, and low TG. Herein, we review the core features of the LEM. We review several existing lines of evidence supporting the model and suggest ways to test the model's predictions.

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