General single-index survival regression models for incident and prevalent covariate data and prevalent data without follow-up

Biometrics ◽  
2017 ◽  
Vol 74 (3) ◽  
pp. 881-890
Author(s):  
Shih-Wei Chen ◽  
Chin-Tsang Chiang
Keyword(s):  
Regression Models ◽  
Covariate Data ◽  
Single Index ◽  
Survival Regression

Demographic factors associated with missed follow-up among solid tumor patients treated at a large multi-site academic institution

2020 ◽  
Vol 16 (32) ◽  
pp. 2635-2643
Author(s):  
Samantha L Freije ◽  
Jordan A Holmes ◽  
Saleh Rachidi ◽  
Susannah G Ellsworth ◽  
Richard C Zellars ◽  
...  
Keyword(s):  
Cancer Patients ◽  
Odds Ratio ◽  
Regression Models ◽  
Tumor Patients ◽  
Logistic Regression Models ◽  
Factors Associated ◽  
Follow Up Care ◽  
Risk Patients ◽  
African American Race

Aim: To identify demographic predictors of patients who miss oncology follow-up, considering that missed follow-up has not been well studies in cancer patients. Methods: Patients with solid tumors diagnosed from 2007 to 2016 were analyzed (n = 16,080). Univariate and multivariable logistic regression models were constructed to examine predictors of missed follow-up. Results: Our study revealed that 21.2% of patients missed ≥1 follow-up appointment. African–American race (odds ratio [OR] 1.33; 95% CI: 1.17–1.51), Medicaid insurance (OR 1.59; 1.36–1.87), no insurance (OR 1.66; 1.32–2.10) and rural residence (OR 1.78; 1.49–2.13) were associated with missed follow-up. Conclusion: Many cancer patients miss follow-up, and inadequate follow-up may influence cancer outcomes. Further research is needed on how to address disparities in follow-up care in high-risk patients.

scholarly journals Low HbA1c levels and all-cause or cardiovascular mortality among people without diabetes: the US National Health and Nutrition Examination Survey 1999–2015

2020 ◽  
Author(s):  
Kosuke Inoue ◽  
Roch Nianogo ◽  
Donatello Telesca ◽  
Atsushi Goto ◽  
Vahe Khachadourian ◽  
...  
Keyword(s):  
Cardiovascular Mortality ◽  
Regression Models ◽  
Machine Learning Algorithms ◽  
Logistic Regression Models ◽  
Health And Nutrition ◽  
Increased Risk ◽  
The Us ◽  
All Cause Mortality ◽  
Hba1c Levels

Abstract Objective It is unclear whether relatively low glycated haemoglobin (HbA1c) levels are beneficial or harmful for the long-term health outcomes among people without diabetes. We aimed to investigate the association between low HbA1c levels and mortality among the US general population. Methods This study includes a nationally representative sample of 39 453 US adults from the National Health and Nutrition Examination Surveys 1999–2014, linked to mortality data through 2015. We employed the parametric g-formula with pooled logistic regression models and the ensemble machine learning algorithms to estimate the time-varying risk of all-cause and cardiovascular mortality by HbA1c categories (low, 4.0 to <5.0%; mid-level, 5.0 to <5.7%; prediabetes, 5.7 to <6.5%; and diabetes, ≥6.5% or taking antidiabetic medication), adjusting for 72 potential confounders including demographic characteristics, lifestyle, biomarkers, comorbidities and medications. Results Over a median follow-up of 7.5 years, 5118 (13%) all-cause deaths, and 1116 (3%) cardiovascular deaths were observed. Logistic regression models and machine learning algorithms showed nearly identical predictive performance of death and risk estimates. Compared with mid-level HbA1c, low HbA1c was associated with a 30% (95% CI, 16 to 48) and a 12% (95% CI, 3 to 22) increased risk of all-cause mortality at 5 years and 10 years of follow-up, respectively. We found no evidence that low HbA1c levels were associated with cardiovascular mortality risk. The diabetes group, but not the prediabetes group, also showed an increased risk of all-cause mortality. Conclusions Using the US national database and adjusting for an extensive set of potential confounders with flexible modelling, we found that adults with low HbA1c were at increased risk of all-cause mortality. Further evaluation and careful monitoring of low HbA1c levels need to be considered.

scholarly journals A systematic review of the quality of conduct and reporting of survival analyses of tuberculosis outcomes in Africa

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Moses M. Ngari ◽  
Susanne Schmitz ◽  
Christopher Maronga ◽  
Lazarus K. Mramba ◽  
Michel Vaillant
Keyword(s):  
Systematic Review ◽  
Sample Size ◽  
Survival Function ◽  
Sample Size Estimation ◽  
Size Estimation ◽  
Survival Curves ◽  
Survival Analyses ◽  
Survival Regression

Abstract Background Survival analyses methods (SAMs) are central to analysing time-to-event outcomes. Appropriate application and reporting of such methods are important to ensure correct interpretation of the data. In this study, we systematically review the application and reporting of SAMs in studies of tuberculosis (TB) patients in Africa. It is the first review to assess the application and reporting of SAMs in this context. Methods Systematic review of studies involving TB patients from Africa published between January 2010 and April 2020 in English language. Studies were eligible if they reported use of SAMs. Application and reporting of SAMs were evaluated based on seven author-defined criteria. Results Seventy-six studies were included with patient numbers ranging from 56 to 182,890. Forty-three (57%) studies involved a statistician/epidemiologist. The number of published papers per year applying SAMs increased from two in 2010 to 18 in 2019 (P = 0.004). Sample size estimation was not reported by 67 (88%) studies. A total of 22 (29%) studies did not report summary follow-up time. The survival function was commonly presented using Kaplan-Meier survival curves (n = 51, (67%) studies) and group comparisons were performed using log-rank tests (n = 44, (58%) studies). Sixty seven (91%), 3 (4.1%) and 4 (5.4%) studies reported Cox proportional hazard, competing risk and parametric survival regression models, respectively. A total of 37 (49%) studies had hierarchical clustering, of which 28 (76%) did not adjust for the clustering in the analysis. Reporting was adequate among 4.0, 1.3 and 6.6% studies for sample size estimation, plotting of survival curves and test of survival regression underlying assumptions, respectively. Forty-five (59%), 52 (68%) and 73 (96%) studies adequately reported comparison of survival curves, follow-up time and measures of effect, respectively. Conclusion The quality of reporting survival analyses remains inadequate despite its increasing application. Because similar reporting deficiencies may be common in other diseases in low- and middle-income countries, reporting guidelines, additional training, and more capacity building are needed along with more vigilance by reviewers and journal editors.

scholarly journals Ethnic differences in the incidence of pterygium in a multi-ethnic Asian population: the Singapore Epidemiology of Eye Diseases Study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiao Ling Fang ◽  
Crystal Chun Yuen Chong ◽  
Sahil Thakur ◽  
Zhi Da Soh ◽  
Zhen Ling Teo ◽  
...  
Keyword(s):  
Ethnic Differences ◽  
Regression Models ◽  
Multivariable Analysis ◽  
Anterior Segment ◽  
Asian Population ◽  
Eye Diseases ◽  
Logistic Regression Models ◽  
Income Status ◽  
Baseline Visit

AbstractWe evaluated the 6-year incidence and risk factors of pterygium in a multi-ethnic Asian population. Participants who attended the baseline visit of the Singapore Epidemiology of Eye Diseases Study (year 2004–2011) and returned six years later, were included in this study. Pterygium was diagnosed based on anterior segment photographs. Incident pterygium was defined as presence of pterygium at 6-year follow-up in either eye, among individuals without pterygium at baseline. Multivariable logistic regression models were used to determine factors associated with incident pterygium, adjusting for baseline age, gender, ethnicity, body mass index, occupation type, educational level, income status, smoking, alcohol consumption, presence of hypertension, diabetes and hyperlipidemia. The overall age-adjusted 6-year incidence of pterygium was 1.2% (95% confidence interval [CI] 1.0–1.6%); with Chinese (1.9%; 95% CI 1.4%-2.5%) having the highest incidence rate followed by Malays (1.4%; 95% CI 0.9%-2.1%) and Indians (0.3%; 95% CI 0.3–0.7%). In multivariable analysis, Chinese (compared with Indians; odds ratio [OR] = 4.21; 95% CI 2.12–9.35) and Malays (OR 3.22; 95% CI 1.52–7.45), male (OR 2.13; 95% CI 1.26–3.63), outdoor occupation (OR 2.33; 95% CI 1.16–4.38), and smoking (OR 0.41; 95% CI 0.16–0.87) were significantly associated with incident pterygium. Findings from this multi-ethnic Asian population provide useful information in identifying at-risk individuals for pterygium.

scholarly journals Kidney Measures with Diabetes and Hypertension on Cardiovascular Disease: The Atherosclerosis Risk in Communities Study

2015 ◽  
Vol 41 (4-5) ◽  
pp. 409-417 ◽  
Author(s):  
Nadine Alexander ◽  
Kunihiro Matsushita ◽  
Yingying Sang ◽  
Shoshana Ballew ◽  
Bakhtawar K. Mahmoodi ◽  
...  
Keyword(s):  
Cardiovascular Risk ◽  
Regression Models ◽  
Estimated Glomerular Filtration Rate ◽  
Cox Regression ◽  
Cardiovascular Outcomes ◽  
Creatinine Ratio ◽  
Atherosclerosis Risk In Communities ◽  
Atherosclerosis Risk ◽  
Lower Egfr

Background: Whether the association of chronic kidney disease (CKD) with cardiovascular risk differs based on diabetes mellitus (DM) and hypertension (HTN) status remains unanswered. Methods: We investigated 11,050 participants from the Atherosclerosis Risk in Communities Study (fourth examination (1996-1998)) with follow-up for cardiovascular outcomes (coronary disease, heart failure and stroke) through 2009. Using the Cox regression models, we quantified cardiovascular risk associated with estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (ACR) in individuals with and without DM and/or HTN and assessed their interactions. Results: Individuals with DM and HTN generally had higher cardiovascular risk relative to those without at all the levels of eGFR and ACR. Cardiovascular risk increased with lower eGFR and higher ACR regardless of DM and HTN status (e.g. adjusted hazards ratio (HR) for eGFR 30-44 vs. 90-104 ml/min/1.73 m2, 2.32 (95% CI, 1.66-3.26) in non-diabetics vs. 1.83 (1.25-2.67) in diabetics and 2.45 (2.20-5.01) in non-hypertensives vs. 1.51 (1.27-1.81) in hypertensives and corresponding adjusted HR for ACR 30-299 vs. <10 mg/g, 1.70 (1.45-2.00) vs. 1.34 (1.10-1.64) and 1.42 (1.10-1.85) vs. 1.57 (1.36-1.81), respectively). Only the ACR-DM interaction reached significance, with a shallower relative risk gradient among diabetics than among non-diabetics (p = 0.02). Analysis of individual cardiovascular outcomes showed similar results. Conclusion: Although individuals with DM and HTN generally had higher cardiovascular risk relative to those without these complications, both low eGFR and high ACR were associated with cardiovascular diseases regardless of the presence or absence of DM and HTN. These findings reinforce the importance of CKD in cardiovascular outcomes.

Relationship Between Mental Health, Resilience, and Physical Activity in Older Adults: A 2-Year Longitudinal Study

2021 ◽  
pp. 1-9
Author(s):  
Maria Priscila Wermelinger Ávila ◽  
Jimilly Caputo Corrêa ◽  
Alessandra Lamas Granero Lucchetti ◽  
Giancarlo Lucchetti
Keyword(s):  
Mental Health ◽  
Physical Activity ◽  
Older Adults ◽  
Regression Models ◽  
Linear Regression Models ◽  
Physically Active ◽  
Effective Interventions ◽  
Self Sufficiency ◽  
The Relationship

The aim of this study was to longitudinally investigate the association between resilience and mental health in older adults and to determine the influence of physical activity on this relationship. A total of 291 older adults were included in a 2-year follow-up study. Adjusted linear regression models evaluated the association between resilience at baseline and mental health after 2 years in sufficiently and insufficiently physically active older adults. A negative correlation was found between resilience at baseline and depression, anxiety, and stress after 2 years for the overall sample. This association changed after stratifying the group. Sufficiently physically active individuals made greater use of the resilience components “Self-Sufficiency” and “Perseverance,” whereas insufficiently physically active individuals made greater use of “Meaning of Life” and “Existential Singularity.” Physical activity can influence the relationship between resilience and mental health. These results can help guide the devising of more effective interventions for this age group.

scholarly journals The prospective relationship between social cohesion and depressive symptoms among older adults from Central and Eastern Europe

2018 ◽  
Vol 73 (2) ◽  
pp. 117-122 ◽  
Author(s):  
Carla Bertossi Urzua ◽  
Milagros A Ruiz ◽  
Andrzej Pajak ◽  
Magdalena Kozela ◽  
Ruzena Kubinova ◽  
...  
Keyword(s):  
Depressive Symptoms ◽  
Eastern Europe ◽  
Social Cohesion ◽  
Regression Models ◽  
Central And Eastern Europe ◽  
The Czech Republic ◽  
Logistic Regression Models ◽  
Z Scores ◽  
Prospective Association

BackgroundSocial cohesion has a potential protective effect against depression, but evidence for Central and Eastern Europe is lacking. We investigated the prospective association between social cohesion and elevated depressive symptoms in the Czech Republic, Russia and Poland, and assessed whether alcohol drinking and smoking mediated this association.MethodsCohort data from 15 438 older urban participants from the Health, Alcohol and Psychosocial factors In Eastern Europe project were analysed. Baseline social cohesion was measured by five questions, and depressive symptoms were measured 3 years later by the 10-item Center for Epidemiological Depression (CES-D) Scale. Nested logistic regression models estimated ORs of elevated depressive symptoms (CES-D 10 score ≥4) by z-scores and tertiles of social cohesion.ResultsPer 1 SD decrease in social cohesion score, adjusted ORs of elevated depressive symptoms were 1.13 (95% CI 1.05 to 1.23) and 1.05 (95% CI 0.99 to 1.13) in men and women, respectively. Further adjustment for smoking and drinking did not attenuate these associations in either men (OR=1.13, 95% CI 1.05 to 1.22) or women (OR=1.05, 95% CI 0.99 to 1.13). Similarly, the fully adjusted ORs comparing the lowest versus highest social cohesion tertile were 1.33 (95% CI 1.10 to 1.62) in men and 1.18 (95% CI 1.01 to 1.39) in women.ConclusionsLower levels of social cohesion was associated with heightened depressive symptoms after a 3-year follow-up among older Czech, Russian and Polish adults. These effects appeared stronger in men, and alcohol and smoking played no appreciable role in this association.

scholarly journals A comparison of surgical pulmonary embolectomy and catheter-directed lysis for life-threatening pulmonary emboli

2019 ◽  
Vol 30 (3) ◽  
pp. 388-393 ◽  
Author(s):  
Amalia A Winters ◽  
Michael J McDaniel ◽  
Jose N Binongo ◽  
Rena C Moon ◽  
Wissam A Jaber ◽  
...  
Keyword(s):  
Regression Models ◽  
Pulmonary Emboli ◽  
Short Term ◽  
Pulmonary Embolectomy ◽  
Treatment Groups ◽  
Catheter Directed Thrombolysis ◽  
Risk Patients ◽  
Life Threatening ◽  
Rv Function

Abstract OBJECTIVES Patients with life-threatening pulmonary emboli (PE) have traditionally been treated with anticoagulation alone, yet emerging data suggest that more aggressive therapy may improve short-term outcomes. The purpose of this study was to compare postoperative outcomes between catheter-directed thrombolysis (CDL) and surgical pulmonary embolectomy (SPE) in the treatment of life-threatening PE. METHODS A retrospective single-centre observational study was conducted for patients who underwent SPE or CDL at a single US academic centre. Preprocedural and postprocedural echocardiographic data were collected. Unadjusted regression models were constructed to assess the significance of the between-group postoperative differences. RESULTS A total of 126 patients suffered a life-threatening PE during the study period [60 SPE (47.6%), 66 CDL 52.4%]. Ten (24.4%) SPE patients and 10 (15.2%) CDL patients had massive PEs marked by preprocedural hypotension. Six (10.0%) SPE patients and 4 (6.0%) CDL patients suffered a preprocedure cardiac arrest (P = 0.41). In-hospital mortality rate was 3.3% (2) for SPE, and 3.0% (2) for CDL (P = 0.99). SPE patients were more likely to require prolonged ventilation (15.0% vs 1.5%, P = 0.01). No significant differences were found in other major complications. At baseline echocardiography, 76.9% of SPE patients and 56.9% of CDL patients had moderate or severe right ventricular (RV) dysfunction. Both treatment groups showed marked and durable improvement in echocardiographic markers of RV function from baseline at midterm follow-up. CONCLUSIONS Both SPE and CDL can be applied to well-selected high-risk patients with low rates of morbidity and mortality. Further research is necessary to delineate which patients would benefit most from either SPE or CDL following a life-threatening PE.

scholarly journals Alcohol consumption and pregnancy in the Mexican national addiction survey

1997 ◽  
Vol 13 (2) ◽  
pp. 205-211 ◽  
Author(s):  
Guilherme Borges ◽  
Roberto Tapia-Conyer ◽  
Malaquías López-Cervantes ◽  
María Elena Medina-Mora ◽  
Blanca Pelcastre ◽  
...  
Keyword(s):  
Alcohol Consumption ◽  
Spontaneous Abortion ◽  
Regression Models ◽  
Congenital Abnormalities ◽  
Adverse Outcomes ◽  
Multiple Logistic Regression ◽  
National Data ◽  
Logistic Regression Models ◽  
Important Relationship

In 1988, the General Directorate of Epidemiology and the Mexican Institute of Psychiatry conducted the first National Addiction Survey (ENA), providing regional and national data on alcohol, tobacco, and drug use. The ENA providing a subsample of women who have been pregnant at some time in their lives. There were 5,234 affirmative responses. Women were asked if they had suffered any of three adverse outcomes during their last pregnancy: spontaneous abortion, stillbirth, and congenital abnormalities. Prevalence of spontaneous abortion was 3.8%, stillbirth 1.2%, and congenital abnormalities 1.1 %. Multiple logistic-regression models were used to analyze the effect of alcohol consumption on these problems. Consumption during pregnancy was related only with the prevalence of congenital abnormalities, with prevalence odds of 3.4. Among habitual users during the last 12 months, oniy women in the highest use category showed an important relationship with the three problems mentioned. Follow-up studies on the Mexican population are recommended in order to obtain more conclusive findings.

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