Estimating hazard ratios from published Kaplan‐Meier survival curves: A methods validation study

BackgroundCoronavirus disease 2019 (COVID-19) has evolved into a pandemic. We hypothesized that biochemical indicators of liver function may help determine the prognosis of COVID-19 patients.MethodsPatient information was collected from the Wuhan-Leishenshan hospital. Logistic and Cox regression analyses, Kaplan-Meier curves, and Curve fitting were used to determine the correlation between elevated levels of aspartate transaminase (AST), alanine transaminase (ALT), and AST/ALT and severity of disease/mortality.ResultsLogistic and Cox regression analyses and Kaplan-Meier survival curves showed that COVID-19 progression correlated with elevated levels of AST and AST/ALT. The odds ratios for elevated levels of AST and AST/ALT in patients were 0.818 (95% confidence interval [CI]: 0.274-2.441, P = 0.035) and 2.055 (95% CI: 1.269-3.327, P = 0.003), respectively; the hazard ratios were 4.195 (95% CI: 1.219-14.422, P = 0.023) and 3.348 (95% CI: 1.57-7.139, P = 0.002), respectively. The Kaplan-Meier survival curves demonstrated that patients with elevated AST and AST/ALT levels had a higher risk of developing severe COVID-19.ConclusionElevated AST and AST/ALT levels correlated with severity of COVID-19 and mortality. Liver function tests may help clinicians in determining the prognosis of patients undergoing treatment for COVID-19.

Download Full-text

Survival of endodontically treated permanent teeth among children: a retrospective cohort study

BMC Oral Health ◽

10.1186/s12903-021-01952-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Saitah Bufersen ◽

Judith Jones ◽

Jayapriyaa Shanmugham ◽

Tun-Yi Hsu ◽

Sharron Rich ◽

...

Keyword(s):

Survival Probability ◽

Total Sample ◽

Permanent Teeth ◽

Age Group ◽

Survival Curves ◽

Endodontically Treated Teeth ◽

Boston University ◽

Kaplan Meier ◽

Hazard Ratios ◽

Increased Risk

Abstract Background Outcome studies of nonsurgical root canal treatment (NSRCT) in permanent teeth of children are scarce. This study investigated survival and assessed the variables associated with failure of endodontically treated teeth (ETT) in 6- to 18-year-olds. Methods Records of subjects who received NSRCT at age 6–18 years at Boston University between 2007 and 2015 were assessed for the occurrence of untoward events. Kaplan–Meier survival curves were used to investigate the survival of ETT in the total sample. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were estimated. Results The analysis included 341 patients (424 ETT). Kaplan–Meier survival curves differed according to age at treatment (log-rank P = 0.026), with survival being the lowest among the youngest age group. The estimated 5-year survival probability was 80% for 15- to 18-year-olds, 64.8% for 12- to 14-year-olds and 46.4% for 6- to 11-year-olds. Compared to age at treatment of 15–18 years, age at treatment of 6–11 years (aHR: 2.19, 95% CI 1.02–4.67) and 12–14 years (aHR: 2.02, 95% CI 1.15–3.55) was associated with an increased risk of ETT failure. In the total study sample, the estimated cumulative survival probability was 93.3% at 12 months, 88.0% at 24 months, 76.2% at 36 months, 71.0% at 48 months, and 69.1% at 60 months. Conclusions In children, ETT are more likely to survive when NSRCTs are performed at an older age.

Download Full-text

COVID-19 related mortality in older adults: analysis of the first wave in Colombia and Mexico

Revista Panamericana de Salud Pública ◽

10.26633/rpsp.2021.109 ◽

2021 ◽

Vol 45 ◽

pp. 1

Author(s):

Mario Ulises Pérez-Zepeda ◽

Santiago Campos-Fajardo ◽

Carlos Cano-Gutierrez

Keyword(s):

Older Adults ◽

Potential Benefit ◽

Open Data ◽

Data Sets ◽

Survival Curves ◽

Continuous Increase ◽

Kaplan Meier ◽

Hazard Ratios ◽

Related Mortality

Objective. The aim of this study is to describe the mortality among older adults in the first wave of COVID-19 in Colombia and Mexico. Methods. This is an observational, prospective study on data obtained from open data sets that are publicly available on the websites of the health ministries of the respective countries. COVID-19 cases, age, sex, date to mortality, and mortality itself were analyzed with Kaplan-Meier curves and Cox regressions. Results. Data on 1 779 877 individuals were analyzed, 58.2% from Mexico, with a higher frequency of men for both countries, and 11.7% were older adults. Survival curves show a continuous increase in mortality for Mexico, with higher rates for older adults, while for Colombia the mortality was observed up to 50 days of the follow-up. Finally, hazard ratios were higher for older adults in both countries. Colombia implemented a rigid curfew for older adults, and the effect on mortality is clear from the survival curves. Conclusions. This finding shows the potential benefit that public policies could have on older adults.

Download Full-text

Outcomes of management of major aortopulmonary collaterals for pulmonary atresia and ventricular septal defect

Cardiology in the Young ◽

10.1017/s1047951120004047 ◽

2020 ◽

pp. 1-9

Author(s):

Dong Zhao ◽

Keming Yang ◽

Wei Feng ◽

Shoujun Li ◽

Jun Yan ◽

...

Keyword(s):

Ventricular Septal Defect ◽

Pulmonary Artery ◽

Septal Defect ◽

Pulmonary Atresia ◽

Survival Curves ◽

Major Aortopulmonary Collateral Arteries ◽

Palliative Procedure ◽

Collateral Arteries ◽

Kaplan Meier ◽

Aortopulmonary Collateral

Abstract Objective: This study aimed to investigate the association between long-term survival and different management of major aortopulmonary collateral arteries in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries. Methods: From November, 2009 to October, 2018, a total of 98 consecutive patients with pulmonary atresia, ventricular septal defect, major aortopulmonary collateral arteries, and hypoplastic pulmonary arteries treated with modified Blalock–Taussig shunt or right ventricle–pulmonary artery connection were included. Fifty-five patients who received occlusion or ligation of major aortopulmonary collateral arteries during or after palliative procedure were occlusion group, and the other 43 patients were no occlusion group. The early and late outcomes were compared. Results: The mean duration of follow-up was 30.9 months in no occlusion group and 49.8 months in the occlusion group (p < 0.001). Multivariate analysis showed that only no occlusion of major aortopulmonary collateral arteries was predictive of total mortality (Hazard Ratio: 4.42, 95% CI: 1.27 to 15.42, p = 0.02). The Kaplan–Meier survival curves confirmed that patients without occlusion of major aortopulmonary collateral arteries demonstrated worse survival as compared with the occlusion group (p = 0.013). The Kaplan–Meier survival curves of patients who underwent different palliative procedures showed no differences. Conclusions: For patients with pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arteries when a primary repair is not feasible, those without occlusion of major aortopulmonary collateral arteries have a higher risk of death following an initial palliative procedure compared with patients who underwent occlusion of major aortopulmonary collateral arteries. The occlusion of major aortopulmonary collateral arteries is not associated with a higher rate of complete repair or better improvement of pulmonary artery growth.

Download Full-text

The Efficacy of Etoposide-Based Therapy in Adult Secondary Hemophagocytic Lymphohistiocytosis

Acta Haematologica ◽

10.1159/000514920 ◽

2021 ◽

pp. 1-9

Author(s):

Leonard Naymagon ◽

Douglas Tremblay ◽

John Mascarenhas

Keyword(s):

Hemophagocytic Lymphohistiocytosis ◽

Proportional Hazards ◽

Multivariable Analysis ◽

Cox Proportional Hazards ◽

Rank Test ◽

Kaplan Meier ◽

Hazard Ratios ◽

Significant Difference ◽

The Impact

Data supporting the use of etoposide-based therapy in hemophagocytic lymphohistiocytosis (HLH) arise largely from pediatric studies. There is a lack of comparable data among adult patients with secondary HLH. We conducted a retrospective study to assess the impact of etoposide-based therapy on outcomes in adult secondary HLH. The primary outcome was overall survival. The log-rank test was used to compare Kaplan-Meier distributions of time-to-event outcomes. Multivariable Cox proportional hazards modeling was used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs). Ninety adults with secondary HLH seen between January 1, 2009, and January 6, 2020, were included. Forty-two patients (47%) received etoposide-based therapy, while 48 (53%) received treatment only for their inciting proinflammatory condition. Thirty-three patients in the etoposide group (72%) and 32 in the no-etoposide group (67%) died during follow-up. Median survival in the etoposide and no-etoposide groups was 1.04 and 1.39 months, respectively. There was no significant difference in survival between the etoposide and no-etoposide groups (log-rank p = 0.4146). On multivariable analysis, there was no association between treatment with etoposide and survival (HR for death with etoposide = 1.067, 95% CI: 0.633–1.799, p = 0.8084). Use of etoposide-based therapy was not associated with improvement in outcomes in this large cohort of adult secondary HLH patients.

Download Full-text

U-survival for prognostic prediction of disease progression and mortality of patients with COVID-19

Scientific Reports ◽

10.1038/s41598-021-88591-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Janne J. Näppi ◽

Tomoki Uemura ◽

Chinatsu Watari ◽

Toru Hironaka ◽

Tohru Kamiya ◽

...

Keyword(s):

Risk Groups ◽

Healthcare Services ◽

Chest Ct ◽

Prediction Performance ◽

Survival Prediction ◽

Concordance Index ◽

Survival Curves ◽

Analysis Methodology ◽

Kaplan Meier ◽

Prognostic Prediction

AbstractThe rapid increase of patients with coronavirus disease 2019 (COVID-19) has introduced major challenges to healthcare services worldwide. Therefore, fast and accurate clinical assessment of COVID-19 progression and mortality is vital for the management of COVID-19 patients. We developed an automated image-based survival prediction model, called U-survival, which combines deep learning of chest CT images with the established survival analysis methodology of an elastic-net Cox survival model. In an evaluation of 383 COVID-19 positive patients from two hospitals, the prognostic bootstrap prediction performance of U-survival was significantly higher (P < 0.0001) than those of existing laboratory and image-based reference predictors both for COVID-19 progression (maximum concordance index: 91.6% [95% confidence interval 91.5, 91.7]) and for mortality (88.7% [88.6, 88.9]), and the separation between the Kaplan–Meier survival curves of patients stratified into low- and high-risk groups was largest for U-survival (P < 3 × 10–14). The results indicate that U-survival can be used to provide automated and objective prognostic predictions for the management of COVID-19 patients.

Download Full-text

Association between severity of prenatally diagnosed hydronephrosis and receipt of surgical intervention postnatally among patients seen at a fetal-maternal center

BMC Urology ◽

10.1186/s12894-021-00822-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Zoë G. Baker ◽

Arthi Hannallah ◽

Melissa Trabold ◽

Danielle Estell ◽

Cherry Deng ◽

...

Keyword(s):

Surgical Intervention ◽

Renal Scarring ◽

Tertiary Care ◽

Rank Test ◽

Kaplan Meier ◽

Hazard Ratios ◽

Age At Surgery ◽

History Of ◽

Pediatric Urologist ◽

Tract Infections

Abstract Background Hydronephrosis (HN) is the most common abnormality detected on prenatal ultrasound. This study sought to stratify outcomes of patients by severity of prenatal HN with postnatal outcomes. Methods This was a retrospective review of patients referred to a tertiary care fetal-maternal clinic with diagnosis of prenatal HN from 2004 to 2019. HN severity was categorized as mild, moderate, or severe. Data were analyzed to determine the association between HN severity and surgical intervention. Decision for surgery was based on factors including history of multiple urinary tract infections, evidence of renal scarring, and/or reduced renal function. Surgery-free survival time was represented by the Kaplan–Meier method, and hazard ratios were calculated using the log-rank test. Results 131 kidneys among 101 infants were prenatally diagnosed with hydronephrosis; 35.9% had mild HN, 29.0% had moderate HN, and 35.1% had severe HN. 8.5% of patients with mild HN, 26.3% of patients with moderate HN, and 65.2% of patients with severe HN required surgery. Patients with severe HN were 12.2 (95% CI 6.1–24.4; p < 0.001) times more likely to undergo surgery for HN than patients with mild HN and 2.9 (95% CI 1.5–5.3; p = 0.003) times more likely to undergo surgery than patients with moderate HN. Patients with moderate HN were 4.3 times more likely to require surgery than patients with mild HN (95% CI 1.5–12.9; p = 0.01). Median age at surgery was 11.8 months among patients with mild HN (IQR 11.7–14.1 months), 6.6 months among patients with moderate HN (IQR 4.2–16.4 months), and 5.4 months among patients with severe HN (3.7–12.4 months). Conclusion Among this cohort of referrals from a fetal-maternal clinic, severity of HN correlated with increased likelihood of surgical intervention. Continued assessment of patients with prenatal HN should be evaluated to best determine the role of the pediatric urologist in cases of prenatal HN.

Download Full-text

Association with Longevity of Phosphatidylinositol 3-Kinase Regulatory Subunit 1 Gene Variants Stems from Protection against Mortality Risk in Men with Cardiovascular Disease

Gerontology ◽

10.1159/000515390 ◽

2021 ◽

pp. 1-9

Author(s):

Timothy A. Donlon ◽

Randi Chen ◽

Kamal H. Masaki ◽

Bradley J. Willcox ◽

Brian J. Morris

Keyword(s):

Cardiovascular Disease ◽

Life Span ◽

Mortality Risk ◽

Regulatory Subunit ◽

Phosphatidylinositol 3 Kinase ◽

Survival Curves ◽

Genotypic Effect ◽

Hazard Ratios ◽

Phosphatidylinositol 3

Introduction: Genetic variation in the phosphatidylinositol 3-kinase reregulatory subunit 1 gene (PIK3R1) is associated with longevity. Objective: The aim of the study was to determine whether cardiovascular disease (CVD) affects this association. Methods: We performed a longitudinal study of longevity-associated PIK3R1 single-nucleotide polymorphism rs7709243 genotype by CVD status in 3,584 elderly American men of Japanese ancestry. Results: At baseline (1991–1993), 2,254 subjects had CVD and 1,314 did not. The follow-up until Dec 31, 2019 found that overall, men with a CVD had higher mortality than men without a CVD (p = 1.7 × 10−5). However, survival curves of CVD subjects differed according to PIK3R1 genotype. Those with longevity-associated PIK3R1 TT/CC had survival curves similar to those of subjects without a CVD (p = 0.11 for TT/CC, and p = 0.054 for TC), whereas survival curves for CVD subjects with the CT genotype were significantly attenuated compared with survival curves of subjects without a CVD (p = 0.0000012 compared with TT/CC, and p = 0.0000028 compared with TC). Men without CVD showed no association of longevity-associated genotype with life span (p = 0.58). Compared to subjects without any CVD, hazard ratios for mortality risk were 1.26 (95% CI, 1.14–1.39; p = 0.0000043) for CT subject with CVD and 1.07 (95% CI 0.99–1.17; p = 0.097) for CC/TT subjects with CVD. There was no genotypic effect on life span for 1,007 subjects with diabetes and 486 with cancer. Conclusion: Our study provides novel insights into the basis for PIK3R1 as a longevity gene. We suggest that the PIK3R1 longevity genotype attenuates mortality risk in at-risk individuals by protection against cellular stress caused by CVD.

Download Full-text

Effects of antiarrhythmic drugs on atrioventricular conduction in patients with preexisting bundle branch block

European Heart Journal ◽

10.1093/ehjci/ehaa946.3358 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

S Kochav ◽

R.C Chen ◽

J.M.D Dizon ◽

J.A.R Reiffel

Keyword(s):

Proportional Hazards ◽

Cox Proportional Hazards ◽

Class I ◽

Class Iii ◽

Bundle Branch Block ◽

Kaplan Meier ◽

Cox Proportional Hazards Models ◽

Hazard Ratios ◽

History Of ◽

Propensity Score Stratification

Abstract Background Theoretical concern exists regarding AV block (AVB) with class I antiarrhythmics (AADs) when bundle branch block (BBB) is present. Whether this is substantiated in real-world populations is unknown. Purpose To determine the relationship between type of AAD and incidence of AVB in patients with preexisting BBB. Methods We retrospectively studied all patients with BBB who received class I and III AADs between 1997–2019 to compare incidence of AVB. We defined index time as first exposure to either drug class and excluded patients with prior AVB or exposed to both classes. Time-at-risk window ended at first outcome occurrence or when patients were no longer observed in the database. We estimated hazard ratios for incident AVB using Cox proportional hazards models with propensity score stratification, adjusting for over 32,000 covariates from the electronic health record. Kaplan-Meier methods were used to determine treatment effects over time. Results Of 40,120 individuals with BBB, 148 were exposed to a class I AAD and 2401 to a class III AAD. Over nearly 4,200 person-years of follow up, there were 22 and 620 outcome events in the class I and class III cohorts, respectively (Figure). In adjusted analyses, AVB risk was markedly lower in patients exposed to class I AADs compared with class III (HR 0.48 [95% CI 0.30–0.75]). Conclusion Among patients with BBB, exposure to class III AADs was strongly associated with greater risk of incident AVB. This likely reflects differences in natural history of patients receiving class I vs class III AADs rather than adverse class III effects, however, the lack of worse outcomes acutely with class I AADs suggests that they may be safer in BBB than suspected. Funding Acknowledgement Type of funding source: None

Download Full-text

Grading system utilising the total score of Oxford classification for predicting renal prognosis in IgA nephropathy

Scientific Reports ◽

10.1038/s41598-021-82967-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoei Miyabe ◽

Kazunori Karasawa ◽

Kenichi Akiyama ◽

Shota Ogura ◽

Tomo Takabe ◽

...

Keyword(s):

Iga Nephropathy ◽

Clinical Findings ◽

Grading System ◽

Oxford Classification ◽

Kaplan Meier ◽

Hazard Ratios ◽

The Oxford Classification ◽

Renal Prognosis ◽

Renal Survival Rate

AbstractThe Oxford classification of IgA nephropathy (IgAN) can evaluate each MEST-C score individually. We analysed a new grading system that utilised the total MEST-C score in predicting renal prognosis. Altogether, 871 IgAN patients were classified into three groups using the new Oxford classification system (O-grade) that utilised the total MEST-C score (O-grade I: 0–1, II: 2–4, and III: 5–7 points), and the 10-year renal prognosis was analysed. The clinical findings became significantly severer with increasing O-grades, and the renal survival rate by the Kaplan–Meier method was 94.1%, 86.9%, and 74.1% for O-grades I, II, and III, respectively. The hazard ratios (HRs) for O-grades II and III with reference to O-grade I were 2.8 (95% confidence interval [CI] 1.3–6.0) and 6.3 (95% CI 2.7–14.5), respectively. In the multivariate analysis, mean arterial pressure and eGFR, proteinuria at the time of biopsy, treatment of corticosteroids/immunosuppressors, and O-grade (HR 1.63; 95% CI 1.11–2.38) were the independent factors predicting renal prognosis. Among the nine groups classified using the O-grade and Japanese clinical-grade, the renal prognosis had an HR of 15.2 (95% CI 3.5–67) in the severest group. The O-grade classified by the total score of the Oxford classification was associated with renal prognosis.

Download Full-text