Chemotherapy/Radiotherapy-Induced Dysphagia in Head and Neck Tumors: A Challenge for Otolaryngologists in Low- to Middle-Income Countries.

Head and neck cancer accounts for 2.8% of all cancers and a large proportion of these patients have a locally advanced stage of the disease, for which chemotherapy and radiation therapy are potentially curative treatments. Dysphagia is one of the most common chemoradiotherapy-related side effects in head and neck cancer since it can lead to life-threatening complications. Reports from the current literature suggest better swallowing outcomes with intensity-modulated radiotherapy (IMRT) compared to three-dimensional conformal radiotherapy (3DCT). However, in low-/middle-income countries, multiple healthcare access barriers to 3DCT that may lead to higher rates of chemo/radiotherapy related adverse events. This narrative review provides a comprehensive appraisal of published peer-reviewed data, as well as a description of the clinical practice in an otolaryngology referral center in Colombia, a low-income country.

Patients on Buprenorphine Formulations Undergoing Surgery.

PURPOSE OF REVIEW: To review the pharmacology of buprenorphine, the evolution of buprenorphine dosing recommendations, and the current literature regarding its recommendations for the perioperative period. RECENT FINDINGS: There is a consensus that for all surgeries, buprenorphine should be continued throughout the perioperative period. If the surgery is a minimal to mild pain surgery, no dose adjustment is needed. There is no clear consensus regarding moderate to severe pain. With all surgeries, multimodal analgesia should be utilized, with regional anesthesia when possible. Patients taking buprenorphine should continue their buprenorphine perioperatively; whether to decrease or maintain dosing is up for debate. Multimodal analgesia should also be used throughout the perioperative period, and communication between the patient and all provider teams is of the utmost importance to provide adequate analgesia during the perioperative period, as well as to arrange safe analgesia upon discharge.

A prospective observational study evaluating the use of remote patient monitoring in ED discharged COVID-19 patients in NYC.

OBJECTIVES: We investigated whether continuous remote patient monitoring (RPM) could significantly reduce return Emergency Department (ED) revisits among coronavirus disease 2019 (COVID-19) patients discharged from the emergency Department. MATERIALS AND METHODS: A prospective observational study was conducted from a total of 2833 COVID-19 diagnosed patients who presented to the Montefiore Medical Center ED between September 2020-March 2021. Study patients were remotely monitored through a digital platform that was supervised 24/7 by licensed healthcare professionals. Age and time-period matched controls were randomly sampled through retrospective review. The primary outcome was ED revisit rates among the two groups. RESULTS: In our study, 150 patients enrolled in the RPM program and 150 controls were sampled for a total of 300 patients. Overall, 59.1% of the patients identified as Hispanic/Latino. The RPM group had higher body mass index (BMI) (29 (25-35) vs. 27 (25-31) p-value 0.020) and rates of hypertension (50.7% (76) vs. 35.8% (54) p-value 0.009). There were no statistically significant differences in rates of ED revisit between the RPM group (8% (12)) and control group (9.3% (14)) (OR: 0.863; 95% CI:0.413-1. 803; p- 0.695). DISCUSSION AND CONCLUSION: Our study explored the impact of continuous monitoring versus intermittent monitoring for reducing ED revisits in a largely underrepresented population of the Bronx. Our study demonstrated that continuous remote patient monitoring showed no significant difference in preventing ED revisits compared to non-standardized intermittent monitoring. However, potential other acute care settings where RPM may be useful for identifying high-risk patients for early interventions warrant further study.

Outcomes of Isolated Tricuspid Valve Surgery.

BACKGROUND: Isolated tricuspid valve surgery is a rarely performed procedure and traditionally is associated with a bad prognosis, although its clinical outcomes still are little known. The aim of this study was to assess the short- and long-term clinical outcomes obtained at our center after isolated tricuspid valve surgery as treatment for severe tricuspid regurgitation. METHODS: This retrospective study included 71 consecutive patients with severe tricuspid regurgitation who underwent isolated tricuspid valve surgery between December 1996 and December 2017. Perioperative and long-term mortality, tricuspid valve reoperation, and functional class were analyzed after follow up. RESULTS: Regarding surgery, 7% of patients received a De Vega annuloplasty, 14.1% an annuloplasty ring, 11.3% a mechanical prosthesis, and 67.6% a biological prosthesis. Perioperative mortality was 12.7% and no variable was shown to be predictive of this event. After a median follow up of 45.5 months, long-term mortality was 36.6%, and the multivariate analysis identified atrial fibrillation as the only predictor (Hazard Ratio 3.014, 95% confidence interval 1.06-8.566; P = 0.038). At the end of follow up, 63.6% of survivors had functional class I. CONCLUSIONS: Isolated tricuspid valve surgery was infrequent in our center. Perioperative mortality was high, as was long-term mortality. However, a high percentage of survivors were barely symptomatic after follow up.

Eliciting inflammation enables successful rehabilitative training in chronic spinal cord injury.

Rehabilitative training is one of the most successful therapies to promote motor recovery after spinal cord injury, especially when applied early after injury. Polytrauma and management of other medical complications in the acute post-injury setting often preclude or complicate early rehabilitation. Therefore, interventions that reopen a window of opportunity for effective motor training after chronic injury would have significant therapeutic value. Here, we tested whether this could be achieved in rats with chronic (8 weeks) dorsolateral quadrant sections of the cervical spinal cord (C4) by inducing mild neuroinflammation. We found that systemic injection of a low dose of lipopolysaccharide improved the efficacy of rehabilitative training on forelimb function, as assessed using a single pellet reaching and grasping task. This enhanced recovery was found to be dependent on the training intensity, where a high-intensity paradigm induced the biggest improvements. Importantly, in contrast to training alone, the combination of systemic lipopolysaccharide and high-intensity training restored original function (reparative plasticity) rather than enhancing new motor strategies (compensatory plasticity). Accordingly, electrophysiological and tract-tracing studies demonstrated a recovery in the cortical drive to the affected forelimb muscles and a restructuration of the corticospinal innervation of the cervical spinal cord. Thus, we propose that techniques that can elicit mild neuroinflammation may be used to enhance the efficacy of rehabilitative training after chronic spinal cord injury.

Cortical electrical stimulation in female rats with a cervical spinal cord injury to promote axonal outgrowth.

Electrical stimulation (ES) to promote corticospinal tract (CST) repair after spinal cord injury (SCI) is underinvestigated. This study is the first to detail intracortical ES of the injured CST. We hypothesize that cortical ES will promote CST collateralization and regeneration, prevent dieback, and improve recovery in an SCI rat model. The CST was transected at the the fourth cervical level in adult female Lewis rats trained in a stairwell grasping task. Animal groups included (a) ES333 (n = 14; 333 Hz, biphasic pulse for 0.2-ms duration every 500 ms, 30 pulses per train); (b) ES20 (n = 14; 20 Hz, biphasic pulse for 0.2-ms duration every 1 s, 60 pulses per train); (c) SCI only (n = 10); and (d) sham (n = 10). ES of the injured forelimb's motor cortex was performed for 30 min immediately prior to SCI. Comparisons between histological data were performed with a 1-way ANOVA or Kruskal-Wallis test, and grasping scores were compared using repeated-measures 2-way ANOVA. Significantly more axonal collateralization was found in ES333 animals compared with controls (p < .01). Axonal dieback analysis revealed ES20 rats to have consistently more dieback than the other groups at all points measured (p < .05). No difference in axonal regeneration was found between groups, nor was there any difference in functional recovery. Cortical ES of the injured CST results in increased collateral sprouting and influences neuroplasticity depending on the ES parameters used. Further investigation regarding optimal parameters and its functional effects is required.

A simple analogy for nervous system plasticity after injury.

When considering plasticity, the central nervous system can be viewed as a building block house. After damage, building components might be lost or loosened and may be rearranged by renovation, analogous to neuroplasticity that occurs after central nervous system injury. In both scenarios, the location and severity of damage will determine the efficacy of renovation/rehabilitation and thus the quality of the adapted structure.

The amplitude of interlimb cutaneous reflexes in the leg is influenced by fingertip touch and vision during treadmill locomotion.

Light touch at the fingertip has been shown to influence postural control during standing and walking. Interlimb cutaneous reflexes have been proposed to provide a neural link between the upper and lower limbs to assist in interlimb coordination during activities such as walking. In this study, we tested the hypothesis that cutaneous sensory pathways linking the arm and leg will be facilitated if subjects use light touch to assist with postural control during treadmill walking. To test this, interlimb cutaneous reflexes from the median nerve, serving the skin contact region, and radial nerve, serving an irrelevant sensory territory, were tested in the legs of subjects walking on treadmill in an unstable environment. Interlimb cutaneous reflexes were tested while subjects (a) touched or (b) did not touch a stable contact with their fingertip, and while the eyes were either (c) open or (d) closed. Reflexes arising from both nerves were facilitated when vision was removed that was then ameliorated when touch was provided. These changes in reflex amplitude during the eyes closed conditions were mirrored by changes in background muscle activity. We suggest that this facilitation of interlimb reflexes from both nerves arises from a generalized increase in excitability related to the postural anxiety of walking on a treadmill with the eyes closed, which is then restored by the provision of light touch. However, the influence of touch when the eyes were open differed depending upon the nerve stimulated. Radial nerve reflexes in the legs were suppressed when touch was provided, mirroring a suppression in the background muscle activity. In contrast, median nerve reflexes in the leg were larger when touch was provided with the eyes open, despite a suppression of background muscle activity. This nerve-specific effect of touch on the amplitude of the interlimb cutaneous reflexes suggests that touch sensory information from the median nerve was facilitated when that input was functionally relevant.

Balance-corrective responses to unexpected perturbations at the arms during treadmill walking.

The arms have been shown to be involved in the regulation of balance during walking. The use of a walking aid enhances balance by increasing the base of support and reducing the load on the legs by partly transferring it to the arms. However, when actively engaged during a balance task, perturbations to the arms can destabilize balance. Previous studies have investigated postural adjustments associated with focal arm movements during standing and walking. However, balance-corrective reactions to unexpected perturbations to the arms during walking have not been well studied. In the present study, subjects walked on a treadmill while grasping a pair of handles when sudden perturbations were delivered by displacing the handles in the forward or backward direction. Instructing subjects to oppose the displacement of the handles resulted in strong responses in the arms that were accompanied by activation of muscles in the legs, comparable to those observed in other balance disturbance studies. Conversely, when subjects were instructed to allow the handles to move when displaced, no responses were observed in the arms. However, similar responses were observed in the legs whether subjects opposed the displacement of the handles or not when perturbations were applied at heel strike. The results from this study show that balance reactions can be elicited in the legs in response to perturbations applied at the arms, and that the expression of these responses is affected by the task engaged in by the arms.

The effect of light touch on the amplitude of cutaneous reflexes in the arms during treadmill walking.

Light touch contact of the tip of one finger can influence the postural control of subjects standing or walking on a treadmill. It is suggested that haptic cues from the finger provide an important sensory cue for the control of posture. In the current study, we used intra-limb cutaneous reflexes in the arms to test the hypothesis that transmission in sensory pathways relevant to the light touch contact would be modulated when light touch is used to increase stability during walking in an unstable environment. Subjects walked on a treadmill and received periodic pulls to the waist. Cutaneous reflexes were evoked from stimulation of the median and radial nerves while the subjects either (a) lightly touched or (b) did not touch a stable contact with the tip of their index finger, while the eyes were either (c) open or (d) closed. The results showed that cutaneous reflexes were modulated by both touch and vision. The effect of touch depended on the nerve being stimulated. The provision of touch in the absence of vision resulted in facilitation of median nerve reflexes evoked in the posterior deltoid and the triceps brachii, but resulted in the suppression of radial nerve reflexes. The nerve-specific influence of touch observed in the responses suggests that cutaneous afferent pathways are facilitated in the presence of touch if they transport sensory information from functionally relevant sensory cues.

The contribution of light touch sensory cues to corrective reactions during treadmill locomotion.

The arms play an important role in balance regulation during walking. In general, perturbations delivered during walking trigger whole-body corrective responses. For instance, holding to stable handles can largely attenuate and even suppress responses in the leg muscles to perturbations during walking. Particular attention has been given to the influence of light touch on postural control. During standing, lightly touching a stable contact greatly reduces body sway and enhances corrective responses to postural perturbations, whereas light touch during walking allows subjects to continue to walk on a treadmill with the eyes closed. We hypothesized that in the absence of mechanical support from the arms, sensory cues from the hands would modulate responses in the legs to balance disturbing perturbations delivered at the torso during walking. To test this, subjects walked on a treadmill while periodically being pulled backwards at the waist while walking. The amplitude of the responses evoked in tibialis anterior to these perturbations was compared across 4 test conditions, in a 2 × 2 design. Subjects either (a) lightly touched or (b) did not touch a stable contact, while the eyes were (c) open or (d) closed. Allowing the subjects to touch a stable contact resulted in a reduction in the amount of fore-aft oscillation of the body on the treadmill, which was accompanied by a reduction in the ongoing electromyographic activity in both tibialis anterior and soleus during undisturbed walking. In contrast, the provision of touch resulted in an increase in the amplitude of the evoked responses in tibialis anterior to the backward perturbations that was more evident when subjects walked with the eyes closed. These results indicate that light touch provides a sensory cue that can be used to assist in stabilizing the body while walking. In addition, the sensory information provided by light touch contributes to the regulation of corrective reactions initiated by balance disturbances encountered during walking.

Technology-based balance performance assessment can eliminate floor and ceiling effects.

Many clinical measurement tools for balance have ceiling effects. Technology-based assessments using virtual reality systems such as the Computer-Assisted Rehabilitation Environment (CAREN) may provide a way to develop objective, quantitative measures that scale from low to high levels of difficulty. Our objective was to: (1) develop a performance assessment tool (PAT) for the CAREN; (2) quantify the reliability of the tool; (3) validate the scores against clinical balance measures; and (4) compare the scores from a population with balance impairments to those from able-bodied individuals in a cross-sectional validation study. Three games were developed on the CAREN and tested on 49 participants (36 able-bodied and 13 with impaired mobility). For each module, the corresponding measures were transformed into scores using a series of functions such that ceiling and flooring effects would be minimized. The results showed an association between scores and age, an overlap in scores from impaired high-performance individuals and able-bodied low performance individuals, and a correlation of PAT scores with other clinical tests. Several of the limitations of current clinical tools, including floor and ceiling effects, were overcome by the PAT, suggesting that the PAT can be used to monitor the effect of rehabilitation and training.

Use of Chitosan from Southern King Crab to Develop Films Functionalized with RGD Peptides for Potential Tissue Engineering Applications.

Southern King Crab (SKC) represents an important fishery resource that has the potential to be a natural source of chitosan (CS) production. In tissue engineering, CS is very useful to generate biomaterials. However, CS has a lack of signaling molecules that facilitate cell-substrate interaction. Therefore, RGD (arginine-glycine-aspartic acid) peptides corresponding to the main integrin recognition site in extracellular matrix proteins have been used to improve the CS surface. The aim of this study was to evaluate in vitro cell adhesion and proliferation of CS films synthesized from SKC shell wastes functionalized with RGD peptides. The FTIR spectrum of CS isolated from SKC shells (SKC-CS) was comparable to commercial CS. Thermal properties of films showed similar endothermic peaks at 53.4 and 53.0 °C in commercial CS and SKC-CS, respectively. The purification and molecular masses of the synthesized RGD peptides were confirmed using HPLC and ESI-MS mass spectrometry, respectively. Mouse embryonic fibroblast cells showed higher adhesion on SKC-CS (1% w/v) film when it was functionalized with linear RGD peptides. In contrast, a cyclic RGD peptide showed similar adhesion to control peptide (RDG), but the highest cell proliferation was after 48 h of culture. This study shows that functionalization of SKC-CS films with linear or cyclic RGD peptides are useful to improve effects on cell adhesion or cell proliferation. Furthermore, our work contributes to knowledge of a new source of CS to synthesize constructs for tissue engineering applications.

Wettability of Amino Acid-Functionalized PSMA Electrospun Fibers for the Modulated Release of Active Agents and Its Effect on Their Bioactivity.

The ideal treatment for chronic wounds is based on the use of bioactive dressings capable of releasing active agents. However, the control of the rate at which these active agents are released is still a challenge. Bioactive polymeric fiber mats of poly(styrene-co-maleic anhydride) [PSMA] functionalized with amino acids of different hydropathic indices and L-glutamine, L-phenylalanine and L-tyrosine levels allowed obtaining derivatives of the copolymers named PSMA@Gln, PSMA@Phe and PSMA@Tyr, respectively, with the aim of modulating the wettability of the mats. The bioactive characteristics of mats were obtained by the incorporation of the active agents Calendula officinalis (Cal) and silver nanoparticles (AgNPs). A higher wettability for PSMA@Gln was observed, which is in accordance with the hydropathic index value of the amino acid. However, the release of AgNPs was higher for PSMA and more controlled for functionalized PSMA (PSMAf), while the release curves of Cal did not show behavior related to the wettability of the mats due to the apolar character of the active agent. Finally, the differences in the wettability of the mats also affected their bioactivity, which was evaluated in bacterial cultures of Staphylococcus aureus ATCC 25923 and methicillin-resistant Staphylococcus aureus ATCC 33592, an NIH/3T3 fibroblast cell line and red blood cells.

[Data availability and morbidity profile in Colombia]. / Disponibilidad de datos y perfil de morbilidad en Colombia.

OBJECTIVE: To characterize morbidity in the Colombian population by diagnosis, sex, age, region, and health coverage system, and evaluate the availability and quality of information on diseases in the country. A descriptive, cross-sectional study to analyze morbidity treated in outpatient visits, hospitalization, and emergencies in Colombia during the 2004-2008 five-year period. METHODS: Based on Colombia's personal health records (Registro Individual de Prestación de Servicios-RIPS), diagnoses were classified according to World Health Organization cause groups. Each cause group for services utilization was differentiated by geographical region, sex, and type of affiliation to the health system. RESULTS: Communicable disease diagnoses were more concentrated in younger age groups, while noncommunicable diseases were more frequent in older age groups. External causes (accidents, self-inflicted injuries, and violence) were a major cause of morbidity and more frequently affected the population aged 5-44 years. Communicable diseases were more prevalent in females (39.98%) than in males (28%), while males were more affected by external causes than females (18.5% and 7.3%, respectively). CONCLUSIONS: Although diagnoses of noncommunicable diseases have increased in Colombia, infections continue to have an important presence in all age groups and health services delivery settings. This situation requires a review of health policies, not only to orient them toward improving the health of the population, but also toward bridging the services gap that exists among the country's different regions. Furthermore, although RIPS are a valuable source of health data, they need to be strengthened with a view to achieving information coverage for all or at least the vast majority of Colombians.

Coaxial fibers of poly(styrene-co-maleic anhydride)@poly(vinyl alcohol) for wound dressing applications: Dual and sustained delivery of bioactive agents promoting fibroblast proliferation with reduced cell adherence.

The prevalence of chronic and acute wounds, as well as the complexity of their treatment represent a great challenge for health systems around the world. In this context, the development of bioactive wound dressings that release active agents to prevent infections and promote wound healing, appears as the most promising solution. In this work, we develop an antibacterial and biocompatible wound dressing material made from coaxial electrospun fibers of poly(styrene-co-maleic anhydride) and poly(vinyl alcohol) (PSMA@PVA). The coaxial configuration of the fibers consists of a shell of poly (styrene-co-maleic anhydride) containing a variable concentration of silver nanoparticles (AgNPs) 0.1-0.6 wt% as antibacterial agent, and a core of PVA containing 1 wt% allantoin as healing agent. The fibers present diameters between 0.72 and 1.7 µm. The release of Ag+ in a physiological medium was studied for 72 h, observing a burst release during the first 14 h and then a sustained and controlled release during the remaining 58 h. Allantoin release curves showed significant release only after 14 h. The meshes showed an antibacterial activity against Pseudomonas aeruginosa and Bacillus subtilis that correlates with the amount of AgNPs incorporated and the release rate of Ag+. Indeed, meshes containing 0.3 and 0.6 wt% of AgNPs showed a 99.99% inhibition against both bacteria. The adherence and cell viability of the meshes were evaluated in mouse embryonic fibroblasts NIH/3T3, observing a significant increase in cell viability after 72 h of incubation accompanied by a reduced adhesion of fibroblasts that decreased in the presence of the active agents. These results show that the material prepared here is capable of significantly promoting fibroblast cell proliferation but without strong adherence, which makes it an ideal material for wound dressings with non-adherent characteristics and with potential for wound healing.

Use of the extended feasible stability region for assessing stability of perturbed walking.

Walking stability has been assessed through gait variability or existing biomechanical measures. However, such measures are unable to quantify the instantaneous risk of loss-of-balance as a function of gait parameters, body sway, and physiological and perturbation conditions. This study aimed to introduce and evaluate novel biomechanical measures for loss-of-balance under various perturbed walking conditions. We introduced the concept of 'Extended Feasible Stability Region (ExFSR)' that characterizes walking stability for the duration of an entire step. We proposed novel stability measures based on the proximity of the body's centre of mass (COM) position and velocity to the ExFSR limits. We quantified perturbed walking of fifteen non-disabled individuals and three individuals with a disability, and calculated our proposed ExFSR-based measures. 17.2% (32.5%) and 26.3% (34.0%) of the measured trajectories of the COM position and velocity during low (high) perturbations went outside the ExFSR limits, for non-disabled and disabled individuals, respectively. Besides, our proposed measures significantly correlated with measures previously suggested in the literature to assess gait stability, indicating a similar trend in gait stability revealed by them. The ExFSR-based measures facilitate our understanding on the biomechanical mechanisms of loss-of-balance and can contribute to the development of strategies for balance assessment.

Immunodetection of rainbow trout IL-8 cleaved-peptide: Tissue bioavailability and potential antibacterial activity in a bacterial infection context.

Chemokines such as IL-8 are part of an important group of proinflammatory response molecules, as well as cell recruitment. However, it has been described in both higher vertebrates and fish that IL-8 has an additional functional role by acting as an antimicrobial effector, either directly or by cleavage of a peptide derived from its C-terminal end. Nevertheless, it is still unknown whether this fragment is released in the context of infection by bacterial pathogens and if it could be immunodetected in tissues of infected salmonids. Therefore, the objective of this research was to demonstrate that the C-terminal end of IL-8 from Oncorhynchus mykiss is cleaved, retaining its antibacterial properties, and that is detectable in tissues of infected rainbow trout. SDS-PAGE and mass spectrometry demonstrated the cleavage of a fragment of about 2 kDa when the recombinant IL-8 was subjected to acidic conditions. By chemical synthesis, it was possible to synthesize this fragment called omIL-8α80-97 peptide, which has antibacterial activity against Gram-negative and Gram-positive bacteria at concentrations over 10 µM. Besides, by fluorescence microscopy, it was possible to locate the omIL-8α80-97 peptide both on the cell surface and in the cytoplasm of the bacteria, as well as inside the monocyte/macrophage-like cell. Finally, by indirect ELISA, Western blot, and mass spectrometry, the presence of the fragment derived from the C-terminal end of IL-8 was detected in the spleen of trout infected with Piscirickettsia salmonis. The results reported in this work present the first evidence about the immunodetection of an antibacterial, and probably cell-penetrating peptide cleaved from the C-terminal end of IL-8 in monocyte/macrophage-like cell and tissue of infected rainbow trout.

Bipolar Disorder and Cardiovascular Risk in Rural versus Urban Populations in Colombia: A Comparative Clinical and Epidemiological Evaluation.

Background: Various multifactorial elements may contribute toward the urban and rural disparities in cardiovascular disease (CVD) risk, particularly among patients with psychiatric diseases. Objective: To investigate whether rural patients diagnosed and treated for Bipolar Disorder (BD) have different risk profiles and outcomes of CVD compared to urban (BD) patients. Methods: We conducted a case-control study that included 125 BD patients (cases) from rural Filadelfia, Colombia and 250 BD patients (controls) treated in Bogotá, Colombia. Cases and controls were 2:1, matched by age and sex. We applied the Framingham Heart Study (FHS) risk calculator to assess risk. Differences by rural/urban status (i.e., case-control status) were assessed by chi-square, paired t-tests, and logistic regression. Findings: Rural BD patients were found to have lower education (p = 1.0 × 10-4), alcohol consumption (p = 3.0 × 10-4), smoking (p = 0.015), psychiatric (p = 1.0 × 10-4) and CV family history (p = 0.0042) compared to urban BD patients. Rural BD patients were 81% more likely to have a more favorable CVD risk profile (OR: 0.19, 95% CI [0.06-0.62]) than urban BD patients, despite rural BD patients having increased CVD morbidity (p = 1.0 × 10-2). Conclusion: Based on increase in morbidity but lower predictive risk in the rural population, our study suggests that the FHS-CVD calculator may not be optimal to assess CVD risk in this population.

The burden of skeletal-related events in four Latin American countries: Argentina, Brazil, Colombia, and Mexico.

AIM: Skeletal-related events (SREs) are major bone complications that frequently occur in patients with solid tumors (ST) and bone metastases, and in patients with multiple myeloma (MM). SREs include pathological fracture, spinal cord compression, radiation to bone, and surgery to bone. Limited data are available regarding the burden of SREs in Latin America. We built an economic model to quantify the current and future economic burden of SREs among adults in four Latin American countries: Argentina, Brazil, Colombia, and Mexico. METHODS: A comprehensive literature review with a systematic search strategy was conducted to parameterize the economic burden of illness (BOI) model. Economic analyses were conducted using a prevalence-based model. Aggregate SRE costs obtained from country-specific sources were used. We also included patient productivity losses. Costs were expressed in 2020 USD for the total annual burden, annual burden per 1,000 at risk, and projected five-year burden. RESULTS: The estimated total number of SREs was 251,503 in 2020, amounting to a total annual cost of USD 1.4 billion. The total projected five-year cost was USD 6.9 billion. Annual costs were highest in Brazil (USD 779.1 million), followed by Mexico (USD 281.8 million), Argentina (USD 174.6 million), and Colombia (USD 120.1 million). The average financial burden per 1,000 at risk was greatest in Brazil (USD 3.6 million), followed by Mexico (USD 3.4 million), Colombia (USD 2.9 million), and Argentina (USD 2.7 million). CONCLUSION: Despite recommendations by medical societies for the use of bone-targeted agents in patients with solid tumors and bone metastasis or with multiple myeloma and bone lesions, a large proportion of patients at risk of experiencing SREs are not treated. Early detection of bone metastases and SREs and the use of the most effective preventative treatments are needed to decrease the clinical and economic burden of SREs in Latin America.