Daily Archives: January 6, 2025

Meta-Analysis: Tailored Hydration Strategies Decrease CI-AKI and MACE in Coronary Angiography

6 Jan, 2025 | 13:00h | UTC

Background: Contrast-induced acute kidney injury (CI-AKI) poses a considerable burden on patients undergoing coronary angiography or percutaneous coronary intervention (PCI). Beyond the direct tubular toxicity of iodine contrast, several risk factors, including chronic kidney disease (CKD) and hemodynamic instability, further increase the likelihood of renal damage. Although guideline-based prevention strategies recommend peri-procedural intravenous hydration, the optimal volume and method remain unclear.

Objective: This meta-analysis aimed to determine whether patient-tailored intravenous fluid administration (using parameters other than body weight alone) can reduce the incidence of CI-AKI, as well as major adverse cardiovascular events (MACE), compared with conventional non-tailored hydration protocols in patients undergoing coronary angiography and/or PCI.

Methods: A systematic review of randomized controlled trials (RCTs) was performed, including 13 studies and 4,458 participants. Tailored hydration strategies encompassed left ventricular end-diastolic pressure (LVEDP)-guided infusion, diuresis-driven matched replacement (RenalGuard®), bioimpedance vector analysis, central venous pressure, or inferior vena cava ultrasound measurements. These were compared against standard non-tailored fluid protocols. The primary outcome was CI-AKI (variously defined but measured within 7 days), and secondary outcomes included MACE, all-cause mortality, and renal replacement therapy (RRT).

Results: Across 12 RCTs (n=3,669), tailored hydration significantly reduced CI-AKI rates (risk ratio 0.56, 95% CI [0.46–0.69], p<0.00001; I²=26%). Ten studies (n=3,377) revealed lower MACE incidence in the tailored hydration arm (RR=0.57, 95% CI [0.42–0.78], p=0.0005; I²=12%). A significant reduction in all-cause mortality (RR=0.57, 95% CI [0.35–0.94], p=0.03) and RRT requirement (RR=0.51, 95% CI [0.29–0.89], p=0.02) was also observed, with no significant increase in pulmonary edema. Subgroup analyses (e.g., CKD) supported the overall benefit of individualizing fluid regimens.

Conclusions: Tailored hydration strategies appear superior to standard approaches in lowering the risk of CI-AKI, MACE, mortality, and RRT after coronary angiography or PCI. Although LVEDP-guided protocols are simple to implement and effective, the RenalGuard® system may offer additional benefits in selected populations, albeit at higher cost and complexity.

Implications for Practice: Clinicians should consider personalized hydration based on physiological or hemodynamic parameters to optimize fluid volume, reduce renal injury, and potentially improve clinical outcomes. Nevertheless, practical challenges include access to specialized equipment and the need for close monitoring in some techniques.

Study Strengths and Limitations: This systematic review highlights consistent treatment effects across diverse RCTs and methods. However, potential biases due to lack of blinding, varying CI-AKI definitions, and limited head-to-head comparisons among tailored approaches constrain definitive conclusions. The small sample size of certain studies and underpowered subgroup analyses also limit the generalizability of findings.

Future Research: Further large-scale trials are warranted to compare various tailored protocols directly, focusing on cost-effectiveness, ease of implementation, and patient-centered endpoints. Ongoing investigations, such as the NEPTUNE trial, aim to clarify whether combining multiple parameters (like LVEDP and contrast volume/eGFR ratio) yields optimal renal protection.

Reference: Cossette F, Trifan A, Prévost-Marcotte G, et al. Tailored Hydration for the Prevention of Contrast-Induced Acute Kidney Injury After Coronary Angiogram or PCI: A Systematic Review and Meta-Analysis. American Heart Journal. Published online January 4, 2025. DOI: http://doi.org/10.1016/j.ahj.2025.01.002

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Meta-analysis: Therapeutic-Dose Heparin Improves 28-Day Mortality in COVID-19 Hospitalized Patients

6 Jan, 2025 | 12:00h | UTC

Background: High rates of thrombotic events and systemic inflammation among COVID-19 hospitalized patients led researchers to test whether intensified anticoagulation strategies could reduce morbidity and mortality. Previous trials yielded conflicting results, partly due to varying doses of anticoagulants—prophylactic, intermediate, or therapeutic—and heterogeneous patient severity. This comprehensive investigation, conducted by the WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group, aimed to clarify the benefits and risks of escalated anticoagulation dosing in patients hospitalized for COVID-19.

Objective: To estimate whether higher-dose anticoagulation (therapeutic or intermediate) improves 28-day all-cause mortality compared with lower-dose anticoagulation (prophylactic or intermediate), and to evaluate secondary outcomes, including progression to mechanical ventilation, thromboembolic events, and major bleeding.

Methods: This prospective meta-analysis included randomized trials comparing higher- versus lower-dose anticoagulation for hospitalized COVID-19 patients. Investigators collected trial-level summary data, focusing primarily on heparins. Dosing categories—therapeutic, intermediate, and prophylactic—were predefined. The main outcome was 28-day mortality; secondary outcomes included progression to invasive mechanical ventilation (IMV), venous or arterial thrombotic events, and major hemorrhage. Data were analyzed using a fixed-effects model, with odds ratios (ORs) pooled across trials.

Results: Overall, 22 trials (over 11 000 total participants) contributed data, primarily evaluating heparins. For therapeutic versus prophylactic-dose heparin, 28-day mortality was significantly reduced (OR, 0.77; 95% CI, 0.64–0.93), especially among patients requiring low-flow oxygen or no supplemental oxygen. Therapeutic dose reduced thromboembolic events (OR 0.48; 95% CI, 0.36-0.64) but increased major bleeding (OR 1.90; 95% CI, 1.19-3.05) compared to prophylactic dose. In contrast, when therapeutic was compared to intermediate-dose heparin, the summary OR for 28-day mortality was 1.21 (CI, 0.93–1.58), suggesting a potential trend toward higher mortality that did not reach statistical significance. Intermediate versus prophylactic-dose comparisons revealed no conclusive mortality difference (OR, 0.95; CI, 0.76–1.19). Across all higher-dose arms, thromboembolic events decreased, while the risk of major bleeding increased, underscoring the delicate risk–benefit balance. Subgroup analyses by respiratory support level, D-dimer, and baseline severity did not indicate strong interaction effects, although sample sizes were limited in more severe illness subgroups.

Conclusions: Therapeutic-dose heparin reduces 28-day mortality relative to prophylactic-dose in hospitalized patients with COVID-19, mainly among those not requiring invasive ventilation. Mortality was similar or potentially worse when therapeutic was compared to intermediate-dose. Clinicians must weigh the lower rate of thrombotic complications against the higher bleeding risk, particularly in critically ill patients.

Implications for Practice: Although higher anticoagulant dosing appears beneficial for certain hospitalized COVID-19 patients, especially those with mild to moderate respiratory compromise, individualized assessment remains key. Current guidelines broadly recommend prophylactic dosing for the critically ill and suggest considering higher doses only in carefully selected patients. Evolving viral variants and changes in standard of care further complicate direct application of these findings to present-day hospital settings.

Study Strengths and Limitations: Strengths include prospective planning, collaboration with multiple trials, and a large pooled sample. Limitations encompass heterogeneity in dose definitions, partial reliance on published data where individual-level parameters could not be fully harmonized, and potential temporal changes in COVID-19 clinical profiles. Moreover, bleeding severity beyond major hemorrhage was not universally reported, limiting robust safety assessments.

Future Research: Further studies should focus on individualized anticoagulant strategies that consider biomarkers (for example, D-dimer) and evolving treatment protocols. Investigations examining optimal timing, duration, and post-discharge management will help refine anticoagulation practices.

Reference:

The WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group. Anticoagulation Among Patients Hospitalized for COVID-19: A Systematic Review and Prospective Meta-analysis. Annals of Internal Medicine. DOI: https://doi.org/10.7326/ANNALS-24-00800

Shappell CN, Anesi GL. Anticoagulation for COVID-19: Seeking Clarity and Finding Yet More Gray. Annals of Internal Medicine. DOI: https://doi.org/10.7326/ANNALS-24-03244

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Review: Nutritional Support in Critically Ill Patients

6 Jan, 2025 | 11:00h | UTC

Introduction: This summary is derived from a state-of-the-art review on nutritional support in the intensive care unit (ICU) published in The BMJ. Critically ill patients experience metabolic disturbances, inflammation, and profound muscle wasting. Nutritional therapy aims to mitigate these effects, though recent randomized controlled trials (RCTs) challenge the dogma of early, aggressive provision of high-calorie and high-protein diets for all ICU patients. Instead, emerging evidence indicates that moderate energy and protein restriction, particularly during the first week, may enhance recovery and reduce complications such as hospital-acquired infections, muscle weakness, and ICU-acquired morbidity. Nonetheless, identifying ideal feeding strategies remains complex, given the dynamic nature of critical illness and the interplay with other interventions such as sedation and physical rehabilitation.

Key Recommendations:

1. Individualized Timing and Dose: Limit caloric and protein loads during the acute phase (roughly the first seven days), especially in patients with hemodynamic instability or shock. Later, as patients transition to recovery, gradually increase macronutrient delivery to meet evolving metabolic needs.
2. Preferred Feeding Route: Enteral nutrition is generally recommended when the gastrointestinal tract is functional, particularly after shock resolution. Parenteral nutrition can be reserved for prolonged gut dysfunction or inability to meet needs enterally. Studies comparing enteral versus parenteral feeding have shown no clear outcome differences, but early enteral feeding is often favored for physiological and cost reasons.
3. Avoid Overfeeding and Overzealous Protein Provision: Several large RCTs (including EFFORT-Protein, EDEN, and NUTRIREA-3) observed no mortality benefit—and in some instances, worse outcomes—when patients received full or high doses of energy and protein in the first week. Metabolic “resistance” and inhibition of protective processes such as autophagy might explain why restricted early feeding sometimes confers advantages.
4. Monitoring and Assessment: Traditional tools (NUTRIC, NRS-2002) and biomarkers (albumin, prealbumin) do not reliably predict who benefits from higher or lower feeding levels. Ultrasound or computed tomography to assess muscle mass may hold promise, but no validated approach exists to guide individualized macronutrient targets.
5. Micronutrients and Specialized Formulations: Broad-spectrum pharmaconutrients (glutamine, antioxidants, etc.) have not improved outcomes in well-powered trials. Instead, standard vitamin and trace element supplementation consistent with recommended daily allowances appears sufficient in most cases.
6. Long-term Rehabilitation: Combined nutritional support and physical exercise are critical for mitigating long-term impacts of ICU-acquired weakness and functional decline. Evidence increasingly highlights the need for prolonged, structured rehabilitation to optimize muscle recovery and quality of life.

Conclusion: Although nutritional support remains central to critical care, it is most effective when carefully adapted to disease phase, patient comorbidities, and evolving organ dysfunction. Key evidence suggests a more conservative approach to energy and protein during the acute phase, followed by gradual escalation and integration with rehabilitation. Ongoing research seeks to identify physiological markers that distinguish when to intensify nutritional therapy and how best to align macronutrient delivery with other therapies to promote muscle function and reduce complications.

Reference: Reignier J, Rice TW, Arabi YM, Casaer M. Nutritional Support in the ICU. BMJ. 2025;388:e077979. DOI: https://doi.org/10.1136/bmj-2023-077979

 

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Clinical Overview of Cervical Cancer: Screening, Treatment, and Future Directions

6 Jan, 2025 | 10:00h | UTC

Introduction: This summary provides a concise review of a comprehensive guideline on cervical cancer, covering its epidemiology, risk factors, clinical presentation, and current therapeutic strategies. The aim is to highlight best practices for prevention, screening, and management, as well as emerging treatments that may shift the standard of care.

Key Recommendations:

1. Prevention and Screening
   • Encourage HPV vaccination before exposure, ideally in adolescence.
   • Perform regular screening with a Papanicolaou test, HPV testing, or both, based on national guidelines.
   • Use colposcopy and directed biopsies for women with abnormal screening results.
2. Early-Stage Disease (FIGO IA to IB2)
   • Offer radical hysterectomy plus pelvic lymphadenectomy; ovarian preservation may be considered for endocrine benefits.
   • Less radical surgery (simple hysterectomy or conization) is now acceptable for smaller tumors (<2 cm) confirmed by imaging and pathology.
   • In selected cases, fertility-sparing radical trachelectomy can be considered, though the SHAPE trial supports more conservative approaches for certain early tumors.
3. Locally Advanced Disease (FIGO IB3 to IVA)
   • Recommend concurrent chemoradiation therapy (daily external-beam radiotherapy, brachytherapy, and weekly cisplatin).
   • Immunotherapy (pembrolizumab) is approved in combination with chemoradiation for FIGO III to IVA disease, demonstrating improved survival.
   • Ensure treatment completion within optimal time frames to maximize therapeutic efficacy.
4. Pelvic Exenteration
   • Consider total pelvic exenteration for isolated central recurrence in patients without distant disease.
   • Thorough psychosocial evaluation is critical before proceeding with this extensive procedure.
5. Metastatic or Recurrent Disease (First-Line Therapy)
   • A platinum-based regimen (cisplatin or carboplatin) combined with paclitaxel, with or without bevacizumab, remains a standard option.
   • For PD-L1–positive tumors, adding pembrolizumab has shown a survival advantage.
   • Bispecific immunotherapy and novel therapeutic regimens are under investigation to improve outcomes further.
6. Second-Line Therapy
   • Tissue factor–directed antibody–drug conjugates (e.g., tisotumab vedotin) are effective for patients whose disease progresses after frontline therapy.
   • HER2-targeted therapies (e.g., trastuzumab deruxtecan) may benefit individuals with HER2-overexpressing cervical tumors.
   • Immune checkpoint inhibitors (cemiplimab, nivolumab) can be used in PD-L1–positive recurrent disease, although prior treatment with pembrolizumab may affect efficacy.

Conclusion: By combining targeted vaccination, robust screening programs, and multidisciplinary treatment strategies, cervical cancer can be dramatically reduced worldwide. Advanced management incorporates state-of-the-art surgical procedures, chemoradiation, immunotherapies, and emerging targeted therapies to extend survival and enhance quality of life. Ongoing research aims to optimize treatment sequencing, define new biomarkers, and advance global eradication efforts.

Reference:
Tewari KS. Cervical Cancer. New England Journal of Medicine. (2025). Link: https://www.nejm.org/doi/full/10.1056/NEJMra2404457

 

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Systemic Therapy for Stage I-III Anal Squamous Cell Carcinoma: Highlights of the ASCO Guideline

6 Jan, 2025 | 09:00h | UTC

Introduction:
This summary presents the key points of the American Society of Clinical Oncology (ASCO) guideline on systemic therapy for patients with stage I-III anal squamous cell carcinoma (SCC). The guideline’s objectives are to offer evidence-based recommendations that support clinicians in selecting radiosensitizing chemotherapy, dosage regimens, treatment strategies, the use of induction chemotherapy, and the use of ongoing adjuvant chemotherapy. This guidance focuses on optimizing chemoradiation (CRT) to improve oncologic outcomes while minimizing toxicities, particularly the myelosuppression that can limit therapy tolerability. Patients who are immunosuppressed and those with comorbidities receive special consideration.

Key Recommendations:

Radiosensitizing Chemotherapy

• Mitomycin-C (MMC) + Fluoropyrimidine: The standard radiosensitizing combination is MMC with fluorouracil (FU). Radiosensitizing means making the cancer cells more sensitive to radiation therapy. MMC with capecitabine (an oral alternative to FU) may also be offered, especially when infusion access is a concern. However, MMC is linked to higher hematologic toxicity, so its use demands vigilant monitoring.
• Cisplatin + FU: An alternative option for radiosensitization. This combination demonstrated noninferiority to MMC + FU in the ACT-II trial. The guideline states that the preferable regimen for patients with immunosuppression is cisplatin and FU, due to the myelosuppression associated with MMC. However, this regimen is not limited to this population. Cisplatin is unsuitable for individuals with renal impairment, significant neuropathy, or hearing loss, and there is no evidence supporting carboplatin substitution.

Dose and Schedule

• MMC + FU: Common regimens include MMC 10 mg/m^2 on days 1 and 29 (with caution on the second dose) or a single dose of 12 mg/m^2 on day 1, along with continuous-infusion FU (1,000 mg/m^2) on days 1–4 and 29–32. Clinicians should note that there is ongoing discussion about giving one versus two MMC doses, given the additional hematologic toxicity and radiation breaks often observed with two cycles.
• MMC + Capecitabine: MMC (single or divided dose as above) plus capecitabine (825 mg/m^2 orally twice daily on radiation days) is often used in practice, although large randomized trial data are lacking.
• Cisplatin + FU: Most commonly, cisplatin 60 mg/m^2 on days 1 and 29, with continuous-infusion FU (1,000 mg/m^2) on days 1–4 and 29–32, can be used. Weekly cisplatin regimens (20 mg/m^2 plus FU 300 mg/m^2) are another acceptable approach, though based on a lower level of evidence.

Single-Agent FU
For patients deemed unable to tolerate combination chemotherapy (e.g., poor performance status), single-agent FU with concurrent radiation may be offered.

Induction and Adjuvant Chemotherapy
No survival or disease-control benefit was observed with adding induction chemotherapy before CRT, nor with additional chemotherapy after CRT for localized anal cancer. Hence, routine use of induction or ongoing adjuvant therapy is not recommended.

Conclusion:
The guideline’s recommendations are based on moderate-quality evidence. These recommendations reinforce the longstanding role of MMC plus FU as the preferred radiosensitizing regimen for stage I-III anal SCC, with cisplatin-based or capecitabine-based options for specific patient needs. The guideline highlights that there are disparities in anal cancer incidence and outcomes, with higher rates among Black men and MSM. These disparities are further complicated by social determinants of health, such as smoking rates, HPV vaccination coverage, and access to screening and treatment. Limiting treatment toxicity—especially myelosuppression—remains critical to preserve treatment adherence and minimize breaks in radiation. Clinicians should tailor therapy to each patient’s comorbidities and performance status. Meanwhile, ongoing trials—such as ECOG-ACRIN 2165 (NCT03233711)—are investigating immunotherapy approaches for higher-risk locally advanced anal cancer, potentially informing future guideline updates.

Reference: Morris VK, Kennedy EB, Amin MA, et al. “Systemic Therapy for Stage I-III Anal Squamous Cell Carcinoma: ASCO Guideline.” Journal of Clinical Oncology. https://doi.org/10.1200/JCO-24-02120

 

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Meta-Analysis: Long Half-Life Phosphodiesterase Inhibitors Reduce HbA1c in Adults with Elevated Baseline Levels

6 Jan, 2025 | 08:00h | UTC

Background: Phosphodiesterase type 5 (PDE5) inhibitors are traditionally used to treat erectile dysfunction and pulmonary arterial hypertension. Recent evidence suggests that PDE5 inhibitors could also be repurposed to lower hemoglobin A1c (HbA1c) in patients with type 2 diabetes. Given the disparity in half-lives among these agents, this meta-analysis focused on whether longer half-life PDE5 inhibitors (tadalafil, PF-00489791) produce a more sustained HbA1c reduction compared to short half-life PDE5 inhibitors (sildenafil, avanafil).

Objective: To evaluate the effect of PDE5 inhibitors on HbA1c levels in individuals with baseline values above 6%, comparing agents with short and long half-lives to assess differential clinical benefits in glycemic control.

Methods: This systematic review and meta-analysis included only randomized controlled trials (RCTs) in which participants received any PDE5 inhibitor for at least four weeks, with control or placebo for comparison. Major databases (Cochrane CENTRAL, PubMed Central, ClinicalTrials.gov, and WHO ICTRP) were searched through September 2024 without language restrictions. Statistical analyses were performed using a random-effects model, reporting mean differences in HbA1c. Secondary outcomes (HOMA-IR, lipid profiles, fasting glucose, and others) were also explored.

Results: Thirteen RCTs were eligible (N=1083). Long half-life agents showed a significant mean reduction of approximately −0.40% in HbA1c (p=0.002) in the overall analysis, whereas short half-life PDE5 inhibitors exhibited no significant change. In more stringent subgroup analyses (≥8 weeks’ duration, exclusive type 2 diabetes, baseline HbA1c ≥6.5%), long half-life PDE5 inhibitors maintained a significant decrease (−0.50%), while short half-life agents paradoxically showed a slight but significant increase (+0.36%, p=0.03). In trials enrolling patients with poorly controlled diabetes (baseline HbA1c near 10%), tadalafil’s HbA1c reductions were considerably larger, aligning with the efficacy of other standard oral antidiabetic medications.

Conclusions: Long half-life PDE5 inhibitors appear to confer meaningful reductions in HbA1c, comparable to established oral antidiabetic agents, particularly in patients whose HbA1c is inadequately controlled. In contrast, short half-life PDE5 inhibitors did not show a consistent benefit and may paradoxically raise HbA1c in certain subgroups, although further large-scale studies are warranted to confirm these findings.

Implications for Practice: Long half-life PDE5 inhibitors could serve as an adjunctive therapy in type 2 diabetes management, especially in individuals with higher baseline HbA1c. Yet, caution is advised given limited data on adverse events and the short duration of most included trials. Physicians should remain prudent until more robust evidence, especially in populations with markedly elevated HbA1c, becomes available.

Study Strengths and Limitations: Strengths include a direct comparison between short and long half-life PDE5 inhibitors in a clinically relevant population, plus systematic subgroup analyses. Limitations involve heterogeneity in trial designs, relatively low baseline HbA1c in most participants, and a lack of long-term follow-up data or major clinical endpoints.

Future Research: Subsequent trials should target populations with poorly controlled diabetes (HbA1c ≥9.0%) and assess longer durations (≥3 months) to capture the full impact of PDE5 inhibitor therapy. A deeper examination of combination regimens, pharmacokinetic optimization, and clinical outcomes like cardiovascular events would further clarify the role of these agents in diabetes care.

Reference: Kim J, Zhao R, Kleinberg LR, Kim K. (2025) “Effect of long and short half-life PDE5 inhibitors on HbA1c levels: a systematic review and meta-analysis.” eClinicalMedicine, 80, 103035. Available at: DOI: http://doi.org/10.1016/j.eclinm.2024.103035

 

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