Direct Oral Anticoagulants for Rheumatic Heart Disease-Associated Atrial Fibrillation Post-Bioprosthetic Mitral Valve Replacement.

BACKGROUND: The efficacy of direct oral anticoagulants (DOACs) in preventing ischemic and thromboembolic events may be suboptimal in atrial fibrillation (AF) patients with rheumatic mitral stenosis. However, their safety and effectiveness after mitral valve replacement (MVR) using bioprosthetic valves is unclear. OBJECTIVES: This study sought to evaluate the safety and effectiveness of DOACs vs warfarin among patients with rheumatic heart disease (RHD)-associated AF after bioprosthetic MVR. METHODS: We performed an observational analysis identifying patients with RHD and AF who underwent bioprosthetic MVR. Primary effectiveness and safety outcomes were ischemic events and major bleeding, respectively. Secondary outcomes included all-cause mortality, cardiac thrombosis, myocardial infarction, and all-cause hospitalization. Propensity score matching was performed to account for the differences in baseline characteristics and comorbidities. RESULTS: A total of 3,950 patients were identified; 76% were on warfarin and 24% on DOAC post-MVR. The DOAC group had a higher burden of baseline comorbidities and prior cardiovascular procedures compared with the warfarin group. The propensity score matching balanced baseline characteristics in 1,832 patients (916 in each group), with a mean age of 69 years. At the 5-year follow-up, DOACs were associated with a lower incidence of major bleeding compared with warfarin (HR: 0.76; 95% CI: 0.62-0.94), with no significant difference in ischemic events, mortality, cardiac thrombosis, myocardial infarction, or hospitalization. CONCLUSIONS: Among patients with RHD-associated AF patients post-bioprosthetic MVR, DOACs are associated with lower major bleeding and comparable effectiveness, indicating a potential alternative to warfarin. Further randomized controlled trials are warranted to validate these findings in this population.

Disparities in the implantation of secondary prevention implantable cardioverter defibrillator in the United States.

BACKGROUND: The annual incidence of sudden cardiac death is over 300,000 in the United States (US). Historically, inpatient implantation of secondary prevention implantable cardioverter defibrillator (ICD) has been variable and subject to healthcare disparities. OBJECTIVE: To evaluate contemporary practice trends of inpatient secondary prevention ICD implants within the US on the basis of race, sex, and socioeconomic status (SES). METHODS: The study is a retrospective analysis of the National Inpatient Sample from 2016 to 2020 of adult discharges with a primary diagnosis of ventricular tachycardia (VT), ventricular flutter, and fibrillation (VF). Adjusted ICD implantation rates based on race, sex, and SES and associated temporal trends were calculated using multivariate regression. RESULTS: A total of 193,600 primary VT/VF discharges in the NIS were included in the cohort, of which 57,895 (29.9%) had ICD placement. There was a significant racial and ethnic disparity in ICD placement for Black, Hispanic, Asian, and Native American patients as compared to White patients; adjusted odds ratio (aOR): 0.86 [p < .01], 0.90 [p  =  .03], 0.81[p < .01], 0.45 [p < .01], respectively. Female patients were also less likely to receive an ICD compared to male patients (aOR: 0.75, p < .01). Disparities in ICD placement remained stable over the study period (ptrend ≥ .05 in all races, both sexes and income categories). CONCLUSION: Racial, sex, and SES disparities persisted for secondary prevention ICD implants in the US. An investigation into contributing factors and subsequent approaches are needed to address the modifiable causes of disparities in ICD implantation as these trends have not improved compared to historic data.

Cardioprotective Potential of Sodium-Glucose Cotransporter-2 Inhibitors in Patients With Cancer Treated With Anthracyclines: An Observational Study.

Anthracyclines are pivotal in cancer treatment, yet their clinical utility is hindered by the risk of cardiotoxicity. Preclinical studies highlight the effectiveness of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in mitigating anthracycline-induced cardiotoxicity. Nonetheless, the translation of these findings to clinical practice remains uncertain. This study aims to evaluate the safety and potential of SGLT2i for preventing cardiotoxicity in patients with cancer, without preexisting heart failure (HF), receiving anthracyclines therapy. Using the TriNetX Global Research Network, patients with cancer, without previous HF diagnosis, receiving anthracycline therapy were identified and classified into 2 groups based on SGLT2i usage. A 1:1 propensity score matching was used to control for baseline characteristics between the 2 groups. Patients were followed for 2 years. The primary end point was new-onset HF, and the secondary end points were HF exacerbation, new-onset arrhythmia, myocardial infarction, all-cause mortality, and all-cause hospitalization. Safety outcomes included acute renal failure and creatinine levels. A total of 79,074 patients were identified, and 1,412 were included post-matching (706 in each group). They comprised 53% females, 62% White, with a mean age of 62.5 ± 11.4 years. Over the 2-year follow-up period, patients on SGLT2i had lower rates of new-onset HF (hazard ratio 0.147, 95% confidence interval 0.073 to 0.294) and arrhythmia (hazard ratio 0.397, 95% confidence interval 0.227 to 0.692) compared with those not on SGLT2i. The incidence of all-cause mortality, myocardial infarction, all-cause hospitalization, and safety outcomes were similar between both groups. In conclusion, among patients with cancer receiving anthracycline therapy without preexisting HF, SGLT2i use demonstrates both safety and effectiveness in reducing anthracycline-induced cardiotoxicity, with a decreased incidence of new-onset HF, HF exacerbation, and arrhythmias.

Percutaneous left atrial appendage closure for stroke prevention in hypertrophic cardiomyopathy patients with atrial fibrillation.

BACKGROUND: Percutaneous left atrial appendage closure (LAAC) is an effective alternative strategy for stroke prevention in patients with atrial fibrillation (AF) at high risk for bleeding with anticoagulation (AC). Efficacy of this strategy in hypertrophic cardiomyopathy (HCM) remains uncertain. OBJECTIVE: The study aimed to compare risk of stroke in HCM-AF patients treated with LAAC with those treated with AC. METHODS: By use of the TriNetX Global Research Network, HCM-AF patients from 2015 to 2024 were assigned to categories of treatment with LAAC and treatment solely with AC and observed for 3 years for ischemic stroke, systemic embolism, and all-cause mortality. Propensity score matching was used to limit confounders. RESULTS: Of 14,867 HCM-AF patients identified, 364 (2.5%) were treated with LAAC vs 14,503 (97.5%) treated with AC. HCM LAAC patients were older (72 vs 67 years; P < .001) and had more comorbidities and more prior bleeding events, including higher rate of prior gastrointestinal bleeding (68% vs 18%; P < .001), compared with HCM patients treated solely with AC. After propensity score matching, there was no baseline difference between groups including prior bleeding events (P > .05). During follow-up, HCM patients treated with LAAC had higher rates of ischemic stroke (13% vs 8%; hazard ratio, 1.9; P = .006) and systemic embolism (14% vs 9%; hazard ratio, 1.8; P = .006) but no difference in mortality compared with matched HCM patients receiving AC. CONCLUSION: These real-world data do not support percutaneous LAAC in HCM-AF patients as the primary treatment strategy during long-term AC to reduce stroke risk. However, LAAC may remain a reasonable option for HCM-AF patients who are unable to tolerate AC because of prohibitive bleeding risk.

Association Between Clinical Trial Participation Status and Outcomes With Mitral Transcatheter Edge-to-Edge Repair.

BACKGROUND: Clinical trials have demonstrated the efficacy and safety of mitral transcatheter edge-to-edge repair (M-TEER) for selected patients with severe mitral regurgitation. However, the generalizability of trial results to real-world patients remains uncertain. OBJECTIVES: The authors aimed to compare baseline characteristics and in-hospital outcomes among trial participants with nonparticipants undergoing M-TEER. METHODS: Using the National Inpatient Sample database years 2016-2020, M-TEER admissions were identified and categorized into trial participants vs none. We also identified a cohort of trial noneligible patients based on clinical exclusion criteria from pivotal trials. Multivariate regression analysis was performed to compare in-hospital outcomes. The primary outcome was in-hospital mortality, and secondary outcomes included in-hospital complications, length of stay, and hospitalization cost. RESULTS: Among 38,770 M-TEER admissions from 2016 to 2020, 11,450 (29.5%) were trial participants, 22,975 (59.3%) were eligible nonparticipants, and 2,960 (7.6%) were noneligible. Baseline characteristics and comorbidity profiles were mostly similar between trial participants vs eligible nonparticipants. In-hospital mortality (adjusted OR [aOR]: 0.98; 95% CI: 0.60-1.62), cardiogenic shock (aOR: 1.06; 95% CI: 0.80-1.42), mechanical circulatory support (aOR: 0.91; 95% CI: 0.58-1.41), mechanical ventilation (aOR: 1.03; 95% CI: 0.74-1.42), and conversion to mitral valve surgery (aOR: 1.08; 95% CI: 0.57-2.03) were not different between both groups. Conversely, M-TEER for noneligible patients was associated with higher rates of mortality (aOR: 6.27; 95% CI: 3.75-10.45) and complications. CONCLUSIONS: The majority of real-world M-TEER patients would have been eligible for clinical trial participation and had comparable clinical profiles and in-hospital outcomes to trial participants. However, noneligible patients had worse in-hospital outcomes compared with trial participants.

Sex differences in myocarditis hospitalizations: Rates, outcomes, and hospital characteristics in the National Readmission Database.

Inflammation of the myocardium, or myocarditis, presents with varied severity, from mild to life-threatening such as cardiogenic shock or ventricular tachycardia storm. Existing data on sex-related differences in its presentation and outcomes are scarce. Using the Nationwide Readmission Database (2016-2019), we identified myocarditis hospitalizations and stratified them according to sex to either males or females. Multivariable regression analyses were used to determine the association between sex and myocarditis outcomes. The primary outcome was in-hospital mortality, and the secondary outcomes included sudden cardiac death (SCD), cardiogenic shock (CS), use of mechanical circulatory support (MCS), and 90-day readmissions. We found a total of 12,997 myocarditis hospitalizations, among which 4,884 (37.6 %) were females. Compared to males, females were older (51 ± 15.6 years vs. 41.9 ± 14.8 in males) and more likely to have connective tissue disease, obesity, and a history of coronary artery disease. No differences were noted between the two groups with regards to in-hospital mortality (adjusted odds ratio [aOR] 1.20; confidence interval [CI] 0.93-1.53; P = 0.16), SCD (aOR:1.18; CI 0.84-1.64; P = 0.34), CS (aOR: 1.01; CI 0.85-1.20;P = 0.87), or use of MCS (aOR: 1.07; CI:0.86-1.34; P = 0.56). In terms of interventional procedures, females had lower rates of coronary angiography (aOR: 0.78; CI 0.70-0.88; P < 0.01), however, similar rates of right heart catheterization (aOR 0.93; CI:0.79-1.09; P = 0.36) and myocardial biopsy (aOR: 1.16; CI:0.83-1.62; P = 0.38) compared to males. Additionally, females had a higher risk of 90-day all-cause readmission (aOR: 1.25; CI: 1.16-1.56; P < 0.01) and myocarditis readmission (aOR:1.58; CI 1.02-2.44; P = 0.04). Specific predictors of readmission included essential hypertension, congestive heart failure, malignancy, and peripheral vascular disease. In conclusion, females admitted with myocarditis tend to have similar in-hospital outcomes with males; however, they are at higher risk of readmission within 90 days from hospitalization. Further studies are needed to identify those at higher risk of readmission.

Transcatheter Aortic Valve Replacement: Variations in Use, Charges, and Geography in the United States.

The use of transcatheter aortic valve replacement (TAVR) in the United States has been increasing but with variability. We used a 100% sample of Medicare beneficiaries (MBs), from the Centers for Medicare and Medicaid Services database, who underwent TAVR by cardiologists between 2015 and 2019. We stratified data by geographic region, rural/urban areas, and provider's gender. We examined the average number of TAVRs performed per 100,000 MBs, the average number of TAVRs performed per individual cardiologist, and the average submitted charge (ASC) per procedure. The number of TAVR per 100,000 MBs was significantly variable among regions in all years (all P≤0.028), except in 2015 (P=0.103), with the highest rates being in the Northeast and the lowest being in the West. The number of TAVRs per cardiologist was significantly different among regions only in 2019 (P=0.04), with the Northeast showing the highest numbers and the South showing the lowest. The ASC was also significantly variable among regions in all years (all P≤0.01). The highest ASC was in the Midwest for all years, whereas the lowest was in the West in 2015 to 2016 and in the South in 2017 to 2019. In all years, the number of TAVRs per cardiologist was higher in urban areas than in rural areas (all P<0.05); however, rural cardiologists had higher ASCs (all P<0.05). The number of TAVR procedures per cardiologist was not significantly different between male and female cardiologists (all P>0.1). Female cardiologists had a significantly higher ASC only in 2015 (P=0.034). In conclusion, there are variations in TAVR use and charges for MBs according to geographic, urban, and rural regions and the performing cardiologist's gender.

Variations in Atrial Fibrillation Ablation Use and Charges in a Modern Cohort of Medicare Beneficiaries.

Catheter ablation of atrial fibrillation (CAF) is increasingly being used in the United States. This study aimed to identify variations in CAF use among Medicare beneficiaries (MBs) over a 6-year period (2013 to 2019). Using the Center of Medicare and Medicaid Services database, a 100% sample of MBs who underwent CAF from 2013 to 2019 was included. We stratified CAF use data geographically (Northeast, South, West, and Midwest) and identified the number of CAFs per 100,000 MBs, number of electrophysiologists performing CAFs per 100,000 MBs, number of CAFs per individual electrophysiologist, and average submitted charge for CAF. In addition, we stratified the data per urban versus rural areas and gender of the operator. We found that the mean atrial fibrillation (AF) prevalence, rates of CAFs, number of electrophysiologists performing CAFs, and number of CAFs per electrophysiologist have increased steadily in all regions. The mean AF prevalence was different among regions, with the highest prevalence in the Northeast (p <0.001); however, there was a pattern of higher CAFs rates in the West and the South (p ≥0.057). The number of electrophysiologists performing CAFs was not different among regions; however, the number of CAFs per electrophysiologist was higher in the West and the South (p <0.001). The average submitted charge for CAF has decreased over years and was the lowest in the West and the South (p <0.001). There was no major difference in these variables regarding operator gender. In conclusion, there are significant variations in CAF use among MBs in the United States according to geographic and urban versus rural regions. These variations have the potential to impact the outcomes in MBs diagnosed with AF.

Disparities in Acute Coronary Syndrome Outcomes in Individuals With Intellectual Disabilities: A Propensity-Matched Analysis of National Inpatient Sample.

BACKGROUND: Individuals with intellectual disabilities (IDs) are at similar risk of acute coronary syndrome (ACS) as compared to general population. However, there is a paucity of real-world data evaluating outcomes of ACS in this population. We sought to study ACS outcomes in individuals with IDs using a large national database. METHODS: Adult admissions with a primary diagnosis of ACS were identified from the national inpatient sample of years 2016-2019. Cohort was stratified according to presence of IDs. A 1 to 1 nearest neighbor propensity score matching using 16 patient variables. Outcomes evaluated were in-hospital mortality, coronary angiography (CA), timing of CA (early [day 0] vs. late [>day0]), and revascularization. RESULTS: A total of 5110 admissions (2555 in each group) were included in our matched cohort. IDs admissions had higher rates of in-hospital mortality (9 % vs. 4 %, aOR: 2.84, 95 % CI [1.66-4.86], P < 0.001), and were less likely to receive CA (52 % vs. 71 %, aOR: 0.44, 95 % CI [0.34-0.58], P < 0.001) and revascularization (33 % vs. 52 %, aOR: 0.45, 95 % CI [0.35-0.58], P < 0.001). In-Hospital mortality was higher in the ID admissions whether invasive coronary treatment (CA or revascularization) was performed (6 % vs. 3 %, aOR: 2.34, 95 % CI [1.09-5.06], P = 0.03) or not (13 % vs. 5 %, aOR: 2.56, 95 % CI [1.14-5.78], P = 0.023). CONCLUSION: Significant disparities exist in ACS outcomes and management in individuals with IDs. More research is needed to understand the reasons for these disparities and develop interventions to improve quality of care in this population.

Personal and community-level exposure to air pollution and daily changes in respiratory symptoms and oxygen saturation among adults with COPD.

Background: Air pollution exposure is associated with hospital admissions for Chronic Obstructive Pulmonary Disease (COPD). Few studies have investigated whether daily personal exposure to air pollutants affects respiratory symptoms and oxygenation among COPD patients. Methodology: We followed 30 former smokers with COPD for up to 4 non-consecutive 30-day periods in different seasons. Participants recorded worsening of respiratory symptoms (sub-categorized as breathing or bronchitis symptoms) by daily questionnaire, and oxygen saturation by pulse oximeter. Personal and community-level exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) were measured by portable air quality monitors and stationary monitors in the Boston area. We used generalized and multi-level linear mixed-effects models to estimate associations of the 24-hour average of each pollutant in the previous day with changes in respiratory symptoms and oxygen saturation. Results: Higher community-level exposure to air pollutants was associated with worsening respiratory symptoms. An interquartile range (IQR) higher community-level O3 was associated with a 1.35 (95%CI: 1.07-1.70) higher odds of worsening respiratory symptoms. The corresponding ORs for community-level PM2.5 and NO2 were 1.18 (95%CI: 1.02-1.37) and 1.06 (95%CI: 0.90-1.25), respectively. Community-level NO2 was associated with worsening bronchitis symptoms (OR=1.25, 95%CI: 1.00-1.56), but not breathing symptoms. Personal PM2.5 exposure was associated with lower odds of worsening respiratory symptoms (OR=0.91; 95%CI: 0.81-1.01). Personal exposure to NO2 was associated with 0.11% lower oxygen saturation (95%CI: -0.22, 0.00) per IQR. Conclusions: In this COPD population, there was a pattern of worsening respiratory symptoms associated with community-level exposure to O3 and PM2.5, and worsening oxygenation associated with personal exposure to NO2.

Non-Small Cell Lung Cancer Presenting as Anterior Nasal Mass and Epistaxis.

Lung malignancy presentation with an uncommon metastatic site is a diagnostic challenge and often associated with poor prognosis. Nasal cavity is a rare metastatic site for any type of lung cancer. We report an unusual case of poorly differentiated adenosquamous carcinoma of the lung with widespread metastasis presenting as a right vestibular nasal mass with epistaxis. A 76-year-old male patient with chronic obstructive pulmonary disease and 80 pack-year smoking history presented with spontaneous epistaxis. He reported a new rapidly growing right-sided nasal vestibular mass first noticed 2 weeks prior. Physical examination showed fleshy mass with crusting in right nasal vestibule along with a left nasal domus mass. Imaging revealed an ovoid mass in the right anterior nostril and a large mass in the right upper lobe of the lung (RULL) along with thoracic vertebral sclerotic metastasis and large left frontal lobe hemorrhagic lesion with severe vasogenic edema. Positron emission tomography scan showed large right upper lobe mass and suspected to be the primary malignancy along with widespread metastasis. Biopsy of the nasal lesion revealed poorly differentiated non-small cell carcinoma with squamous and glandular features. The diagnosis of very poorly differentiated adenosquamous carcinoma of the lung with widespread metastasis was made. In conclusion, unusual metastatic sites with unknown primary lesions require a thorough diagnostic workup involving biopsy and extensive imaging. Lung cancer with unusual metastatic sites is inherently aggressive and associated with poor prognosis. Multidisciplinary treatment modalities should be employed keeping in view the functional status and comorbidities of the patient.

Impact of chronic kidney disease on in-hospital mortality and clinical outcomes of catheter ablation of ventricular tachycardia: Insights from the national readmission database.

BACKGROUND: Catheter ablation is an effective treatment for ventricular tachycardia (VT), albeit the decision to undergo this procedure is often influenced by underlying comorbidities. The present study aims at evaluating the effects of chronic kidney disease (CKD) on clinical outcomes of VT ablation. METHODS: We identified 7212 patients who presented between 2016 and 2018 and underwent catheter ablation for VT. Their clinical data were retrospectively accrued from the national readmission database (NRD) using the corresponding diagnosis codes. We compared clinical outcomes between patients with chronic kidney disease (CKD group) and patients without. Odds ratios (OR) for the primary and secondary outcomes were calculated, and multivariable regression analysis was utilized to adjust for confounding variables. RESULTS: Compared with patients without CKD, patients in CKD group were older (mean age 67.9 vs. 60.5 years, P < 0.01), had a longer mean length of stay (8.73 vs. 5.69 days, P < 0.01), and higher in-hospital mortality 113 (6.7%) vs. 119 (2.2%) (OR 2.24, 95% confidence interval (CI) (1.29-3.88), P < 0.01). CKD group patients had increased risk of developing acute kidney injury 726 (43%) vs. 623 (11.3%) (3.69 95% CI (2.87-4.74), P < 0.01). CONCLUSION: In patients with CKD, VT ablation is associated with worse clinical outcomes in-hospital mortality, acute kidney injury, mean length of stay, and total hospital charge. This significantly influences the decision-making prior to performing this procedure.

Systemic anti-inflammatory effects of mesenchymal stem cells in burn: A systematic review of animal studies.

Background: Despite the advances in burn care, severe burns still impose significant morbidity and mortality. Severe burns are associated with an inflammatory response that ranges from alterations in vital signs to shock, multiorgan failure, and death. Mesenchymal stem cells (MSCs) are known for their anti-inflammatory and immunomodulatory effects. Therefore, MSCs were investigated for their potential benefits in modulating burn-induced inflammation and organ damage in several studies. Aim: We have conducted a systematic review of the literature to evaluate the efficacy of MSCs in modulating burn-induced systemic inflammation and organ damage in animal models. Methods: Four databases were searched: PubMed, Cumulative Index of Nursing and Allied Health Literature, Scopus, and Web of Science. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analysis as our basis of organization. Results: Eight studies were included in the study. Bone marrow derived MSCs, umbilical cord derived MSCs (UC-MSCs), and UC-MSCs exosomes were used to modulate the burn-induced inflammation. MSCs therapy reduced serum levels of pro-inflammatory cytokines, improved renal function, inhibited tissue damage, and improved survival after burn. Furthermore, MSCs reversed all the burn-induced pathological changes in blood brain barrier (BBB). Conclusion: MSCs may attenuate the burn-induced inflammation by decreasing serum levels of inflammatory cytokines. However, the effect on anti-inflammatory cytokines is conflicting and mandates more substantial evidence. Furthermore, MSCs reduce tissue inflammation, tissue damage, and apoptosis in the lungs and kidneys. In addition, MSCs reversed the burn-induced pathophysiologic changes in the BBB. The underlying mechanisms of these effects are poorly understood and should be the focus of future stem cell research. Relevance to Patients: Severe burn patients are liable to systemic inflammation due to the release of inflammatory cytokines into the circulation. This inflammatory response has a broad spectrum of severity that ranges from alterations in vital signs to multiorgan failure and death. Despite the advances in burn care, burn-induced inflammation still imposes significant morbidity and mortality. This systematic review evaluates the potential benefits of stem cells in modulating burn-induced systemic inflammation in animal burn models.

Surgical Management of Aortic Regurgitation in Takayasu's Arteritis: A Systematic Review of Techniques and Outcomes.

IntroductionTakayasu's arteritis (TA) is an inflammatory condition that affects large vessels and frequently involves the aortic valve causing valve regurgitation. Surgical management is recommended for symptomatic severe aortic regurgitation (AR); however, the optimal surgical approach is yet unclear. This study aims to review surgical treatment options for AR in TA and determine which procedure has a lower chance of late postoperative events and/or mortality. MethodsAn electronic database search was performed within PubMed, EMBASE, Web of Science, and SCOPUS to identify articles from 1975 to 2016 focusing on surgical management of the AR in TA. ResultsTwenty seven studies encompassing a total of 194 cases (77% females) were included. Isolated aortic valve replacement (AVR) was performed in 105/194 cases (54%) (Group A), while combined aortic valve and root replacement (CAVRR) was performed in 87/194 (45%) (Group B). Prosthetic valve detachment was reported in 10/105 cases (9.5%) in group A and 1/87 cases (1.2%) in group B (p = 0.02). Dilation of the residual aorta was reported in 10/105 cases (9.5%) in group A and 1/87 cases (1.2%) in group B (p = 0.02). Any late (≥ 30 d) postoperative cardiac event was reported in 26/105 cases (24.8%) in group A, and in 7/87 cases (8.1%) in group B (p = 0.003). ConclusionsAlthough CAVRR is a more complex procedure, it might offer a better outcome in terms of late postoperative cardiac events compared to isolated AVR procedure. Future prospective studies are required to help determine the best surgical approach in such a population.

The impact of personal and outdoor temperature exposure during cold and warm seasons on lung function and respiratory symptoms in COPD.

Rationale: Chronic obstructive pulmonary disease (COPD) patients often report aggravated symptoms due to heat and cold, but few studies have formally evaluated this. Methodology: We followed 30 Boston-based former smokers with COPD for four non-consecutive 30-day periods over 12 months. Personal and outdoor temperature exposure were measured using portable and Boston-area outdoor stationary monitors. Participants recorded daily morning lung function measurements as well as any worsening breathing (breathlessness, chest tightness, wheeze) and bronchitis symptoms (cough, sputum colour and amount) compared to baseline. Using linear and generalised linear mixed-effects models, we assessed associations between personal and outdoor temperature exposure (1-3-day moving averages) and lung function and symptoms, adjusting for humidity, smoking pack-years and demographics. We also stratified by warm and cold season. Results: Participants were on average 71.1±8.4 years old, with 54.4±30.7 pack-years of smoking. Each 5°C increase in personal temperature exposure was associated with 1.85 (95% CI 0.99-3.48) higher odds of worsening breathing symptoms. In the warm season, each 5°C increase in personal and outdoor temperature exposure was associated with 3.20 (95% CI 1.05-9.72) and 2.22 (95% CI 1.41-3.48) higher odds of worsening breathing symptoms, respectively. Each 5°C decrease in outdoor temperature was associated with 1.25 (95% CI 1.04-1.51) higher odds of worsening bronchitis symptoms. There were no associations between temperature and lung function. Conclusions: Our findings suggest that higher temperature, including outdoor exposure during the warm season and personal temperature exposure year-round, may worsen dyspnoea, while colder outdoor temperature may trigger cough and phlegm symptoms among COPD patients.