Nested Case Control Design Research Articles

Nested case–control sampling without replacement

Nested case–control design (NCC) is a cost-effective outcome-dependent design in epidemiology that collects all cases and a fixed number of controls at the time of case diagnosis from a large cohort. Due to inefficiency relative to full cohort studies, previous research developed various estimation methodologies but changing designs in the formulation of risk sets was considered only in view of potential bias in the partial likelihood estimation. In this paper, we study a modified design that excludes previously selected controls from risk sets in view of efficiency improvement as well as bias. To this end, we extend the inverse probability weighting method of Samuelsen which was shown to outperform the partial likelihood estimator in the standard setting. We develop its asymptotic theory and a variance estimation of both regression coefficients and the cumulative baseline hazard function that takes account of the complex feature of the modified sampling design. In addition to good finite sample performance of variance estimation, simulation studies show that the modified design with the proposed estimator is more efficient than the standard design. Examples are provided using data from NIH-AARP Diet and Health Cohort Study.

Reinforcement learning for individualized lung cancer screening schedules: A nested case–control study

AbstractBackgroundThe current guidelines for managing screen‐detected pulmonary nodules offer rule‐based recommendations for immediate diagnostic work‐up or follow‐up at intervals of 3, 6, or 12 months. Customized visit plans are lacking.PurposeTo develop individualized screening schedules using reinforcement learning (RL) and evaluate the effectiveness of RL‐based policy models.MethodsUsing a nested case–control design, we retrospectively identified 308 patients with cancer who had positive screening results in at least two screening rounds in the National Lung Screening Trial. We established a control group that included cancer‐free patients with nodules, matched (1:1) according to the year of cancer diagnosis. By generating 10,164 sequence decision episodes, we trained RL‐based policy models, incorporating nodule diameter alone, combined with nodule appearance (attenuation and margin) and/or patient information (age, sex, smoking status, pack‐years, and family history). We calculated rates of misdiagnosis, missed diagnosis, and delayed diagnosis, and compared the performance of RL‐based policy models with rule‐based follow‐up protocols (National Comprehensive Cancer Network guideline; China Guideline for the Screening and Early Detection of Lung Cancer).ResultsWe identified significant interactions between certain variables (e.g., nodule shape and patient smoking pack‐years, beyond those considered in guideline protocols) and the selection of follow‐up testing intervals, thereby impacting the quality of the decision sequence. In validation, one RL‐based policy model achieved rates of 12.3% for misdiagnosis, 9.7% for missed diagnosis, and 11.7% for delayed diagnosis. Compared with the two rule‐based protocols, the three best‐performing RL‐based policy models consistently demonstrated optimal performance for specific patient subgroups based on disease characteristics (benign or malignant), nodule phenotypes (size, shape, and attenuation), and individual attributes.ConclusionsThis study highlights the potential of using an RL‐based approach that is both clinically interpretable and performance‐robust to develop personalized lung cancer screening schedules. Our findings present opportunities for enhancing the current cancer screening system.

Absolute risk from double nested case-control designs: cause-specific proportional hazards models with and without augmented estimating equations.

We estimate relative hazards and absolute risks (or cumulative incidence or crude risk) under cause-specific proportional hazards models for competing risks from double nested case-control (DNCC) data. In the DNCC design, controls are time-matched not only to cases from the cause of primary interest, but also to cases from competing risks (the phase-two sample). Complete covariate data are available in the phase-two sample, but other cohort members only have information on survival outcomes and some covariates. Design-weighted estimators use inverse sampling probabilities computed from Samuelsen-type calculations for DNCC. To take advantage of additional information available on all cohort members, we augment the estimating equationswith a term that is unbiased for zero but improves the efficiency of estimates from the cause-specific proportional hazards model. We establish the asymptotic properties of the proposed estimators, including the estimator of absolute risk, and derive consistent variance estimators. We show that augmented design-weighted estimators are more efficient than design-weighted estimators. Through simulations, we show that the proposed asymptotic methods yield nominal operating characteristics in practical sample sizes. We illustrate the methods using prostate cancer mortality data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Study of the National Cancer Institute.

***ECD*** maternal C-reactive protein as a predictor of neonatal sepsis

ABSTRACT Systemic bacterial infection in the newborn has a significant impact on neonatal mortality and morbidity. Non-invasive prenatal markers of risk could be useful in the prediction and prevention of neonatal sepsis. We evaluated the association of maternal third-trimester serum level of C-Reactive Protein (CRP) with neonatal sepsis in a sample of infants in the JAKids pregnancy and birth cohort study. A population-based nested case–control design was used to identify cases and controls of neonatal sepsis from the subset of infants in the JAKids study whose mothers had serum archived in the early third trimester and who were admitted to newborn intensive care. Cases were 25 neonates with neonatal sepsis identified from hospital records. Controls were a random sample of 62 sepsis-free neonates matched to cases within three gestational age strata – ≤32 weeks, 33–36 weeks, and ≥37 weeks. Mothers of neonatal sepsis cases ≥37 weeks had significantly higher mean levels of maternal CRP protein than mothers of controls (11.0 mg/dL ± 3.0 vs. 8.7 mg/dL ± 5.9; p < .05). Differences in maternal CRP were not found in sepsis cases born ≤32 weeks (9.5 mg/dL ± 4.2 vs 5.8 mg/dL ± 4.0, p = .23) nor in sepsis cases born at 33–36 weeks (9.0 mg/dL ± 3.6 vs 11.9 mg/dL ± 7.8, p = .34). Maternal third-trimester C-reactive protein levels were elevated in mothers of term-born neonates with sepsis, but not in the mothers of preterm neonates with sepsis.

The impact of Renin-Angiotensin System Inhibitors on bone fracture risk: a nationwide nested case-control study

BackgroundThe therapeutic efficacy of renin-angiotensin system inhibitors (RASi) in elderly patients with hypertension and at risk of fractures has been in the limelight because of accumulating evidence that localized RAS activation in bone tissue leads to osteoclastic bone resorption, resulting in osteoporosis. This study set out to investigate the association between RASi use and fracture incidence in a large cohort.MethodsWe employed a nested case–control design to investigate the association between RASi use and newly developed fractures. A case was defined as a patient newly diagnosed with a fracture between January 2004 and December 2015. We selected 1,049 cases and controls using 1:1 propensity score matching. Conditional logistic regression analysis was conducted to estimate the association between RASi exposure and fracture incidence.ResultsOverall, RASi usage was significantly associated with lower odds for fracture incidence (ever-users vs never-users: OR, 0.73; 95% CI, 0.59–0.91). We found that ARB-only users experienced fewer fractures than RASi-never users (OR, 0.65; 95% CI, 0.49–0.86), whereas ACEi-only users or ARB/ACEi-ever users did not. In subgroup analysis, RASi-ever users without cerebrovascular disease, those with a BMI exceeding 23, and statin exposure had significantly lower ORs.ConclusionsThe present study established a significant association between RASi use and reduced fracture incidence, thus highlighting the potential clinical utility of RASi use as a preventive strategy in elderly patients at risk for osteoporotic fractures.

Subjective cognitive complaints and blood biomarkers of neurodegenerative diseases: a longitudinal cohort study

BackgroundSubjective cognitive complaints (SCC) have been mostly studied in the context of Alzheimer’s disease in memory clinic settings. The potential of combining SCC with genetic information and blood biomarkers of neurodegenerative diseases for risk assessment of dementia and depression in the absence of dementia among community-dwelling older adults has so far not been explored.MethodsData were based on a population-based cohort of 6357 participants with a 17-year follow-up (ESTHER study) and a clinic-based cohort of 422 patients. Participants of both cohorts were grouped according to the diagnosis of dementia (yes/no) and the diagnosis of depression in the absence of dementia (yes/no). Participants without dementia included both cognitively unimpaired participants and cognitively impaired participants. Genetic information (APOE ε4 genotype) and blood-based biomarkers of neurodegenerative diseases (glial fibrillary acidic protein; GFAP, neurofilament light chain; NfL, phosphorylated tau181; p-tau181) were available in the ESTHER study and were determined with Simoa Technology in a nested case–control design. Logistic regression models adjusted for relevant confounders were run for the outcomes of all-cause dementia and depression in the absence of dementia.ResultsThe results showed that persistent SCC were associated both with increased risk of all-cause dementia and of depression without dementia, independently of the diagnostic setting. However, the results for the ESTHER study also showed that the combination of subjective complaints with APOE ε4 and with increased GFAP concentrations in the blood yielded a substantially increased risk of all-cause dementia (OR 5.35; 95%CI 3.25–8.81, p-value < 0.0001 and OR 7.52; 95%CI 2.79–20.29, p-value < 0.0001, respectively) but not of depression. Associations of NfL and p-tau181 with risk of all-cause dementia and depression were not statistically significant, either alone or in combination with SCC, but increased concentrations of p-tau181 seemed to be associated with an increased risk for depression.ConclusionIn community and clinical settings, SCC predict both dementia and depression in the absence of dementia. The addition of GFAP could differentiate between the risk of all-cause dementia and the risk of depression among individuals without dementia.

Study design for development of novel safety biomarkers of drug-induced liver injury by the translational safety biomarker pipeline (TransBioLine) consortium: a study protocol for a nested case–control study

A lack of biomarkers that detect drug-induced liver injury (DILI) accurately continues to hinder early- and late-stage drug development and remains a challenge in clinical practice. The Innovative Medicines Initiative’s TransBioLine consortium comprising academic and industry partners is developing a prospective repository of deeply phenotyped cases and controls with biological samples during liver injury progression to facilitate biomarker discovery, evaluation, validation and qualification.In a nested case–control design, patients who meet one of these criteria, alanine transaminase (ALT) ≥ 5 × the upper limit of normal (ULN), alkaline phosphatase ≥ 2 × ULN or ALT ≥ 3 ULN with total bilirubin > 2 × ULN, are enrolled. After completed clinical investigations, Roussel Uclaf Causality Assessment and expert panel review are used to adjudicate episodes as DILI or alternative liver diseases (acute non-DILI controls). Two blood samples are taken: at recruitment and follow-up. Sample size is as follows: 300 cases of DILI and 130 acute non-DILI controls. Additional cross-sectional cohorts (1 visit) are as follows: Healthy volunteers (n = 120), controls with chronic alcohol-related or non-alcoholic fatty liver disease (n = 100 each) and patients with psoriasis or rheumatoid arthritis (n = 100, 50 treated with methotrexate) are enrolled. Candidate biomarkers prioritised for evaluation include osteopontin, glutamate dehydrogenase, cytokeratin-18 (full length and caspase cleaved), macrophage-colony-stimulating factor 1 receptor and high mobility group protein B1 as well as bile acids, sphingolipids and microRNAs. The TransBioLine project is enabling biomarker discovery and validation that could improve detection, diagnostic accuracy and prognostication of DILI in premarketing clinical trials and for clinical healthcare application.

Prenatal metal levels and congenital anomalies of the kidney and urinary tract: The Japan Environment and Children's Study

BackgroundPrenatal exposure to metal elements has been reported as a potential risk factor for congenital malformation. However, studies on the relationship with congenital anomalies of the kidney and urinary tract (CAKUT) are very scarce. MethodsParticipants of a prospective cohort from the Japan Environment and Children's Study, conducted at 15 research centers, were recruited between January 2011 and March 2014. The exposure factors were concentrations of lead (Pb), cadmium (Cd), mercury (Hg), selenium (Se), and manganese (Mn) measured from maternal whole blood in the second or third trimester. The primary outcome was CAKUT diagnosed during the first three years of life, which was classified into isolated cases and complicated cases accompanied by extrarenal congenital defects. To conduct a nested case–control design within the cohort, we selected 351 isolated cases with 1404 matched controls, and 79 complicated cases with 316 matched controls. ResultsA logistic regression model was used to examine the associations between individual metal concentrations and each subtype of CAKUT. A higher level of Se was associated with an increased risk of isolated CAKUT (adjusted odds ratio [95 % confidence interval]: 3.22 [1.33–7.77]). Meanwhile, higher levels of Pb and Mn were associated with a reduced risk of the complicated subtype (0.46 [0.24–0.90] and 0.33 [0.15–0.73], respectively). A Bayesian kernel machine regression model accounting for mixed effects of multiple metals further demonstrated that a higher level of Mn alone was significantly associated with a reduced occurrence of the complicated subtype. ConclusionsUsing a stringent statistical approach, the present study demonstrated that a higher Mn concentration in the maternal blood was associated with a lower risk of complicated CAKUT in offspring. Further cohort and experimental studies are needed to verify the clinical impact of this finding.

Hypnotics and injuries among older adults with Parkinson’s disease: a nested case–control design

BackgroundPatients with Parkinson’s disease often experience sleep disorders. Hypnotics increase the risk of adverse events, such as injuries due to falls. In this study, we evaluated the association between hypnotics and injuries among older adults with Parkinson’s disease.MethodsThe study used a nested case–control design. The participants were 5009 patients with Parkinson’s disease aged ≥ 75 years based on claims data between April 2016 and March 2019 without prescription hypnotics 1 year before the study started. Hypnotics prescribed as oral medications included benzodiazepines, non-benzodiazepines, orexin receptor antagonists, and melatonin receptor agonists. The incidences of outcomes, including injuries, fractures, and femoral fractures, were determined. Each case had four matched controls. Conditional logistic regression analyses were performed to calculate the odds ratios and 95% confidence intervals for the number of hypnotics taken per day for each type of hypnotic.ResultsThe proportion of participants taking at least one type of hypnotic was 18.6%, with benzodiazepines being the most common. The incidence of injuries, fractures, and femoral fractures was 66.7%, 37.8%, and 10.2%, respectively. Benzodiazepines significantly increased the risk of injuries (odds ratio: 1.12; 95% confidence interval: 1.03–1.22), and melatonin receptor agonists significantly increased the risk of femoral fractures (odds ratio: 2.84; 95% confidence interval: 1.19–6.77).ConclusionsBenzodiazepines and non-benzodiazepines, which are not recommended according to current guidelines, were the most prevalent among older adults with Parkinson’s disease. Benzodiazepines significantly increased the risk of injuries, and melatonin receptor agonists significantly increased the risk of femoral fractures.

Calculating surgical readmission rates in gynecologic oncology: The impact of patient factors

ObjectiveTo determine the 30-day surgical readmission rate after major gynecologic oncology surgeries at a high-volume academic institution and correlated risk factors. MethodsRetrospective cohort study was conducted of surgical admissions from January 2016 – December 2019 at a single institution. Data were extracted from patient charts, including reason for readmission and length of stay. A readmission rate was calculated. Nested case control design was used to identify correlations between readmission and patient specific risk-factors. Multivariable logistic regression models were used to determine risk factors with readmission. ResultsA total of 2152 patients were included. The readmission rate was 3.5%, most commonly due to GI disturbance and surgical site infection. Average readmission length was 5 days. Prior to adjusting for covariates, insurance status, primary diagnosis, index admission length, and disposition at discharge differed between patients who were and were not readmitted. After adjusting for co-variates, younger patients, index admission >2 days, and higher Charlson co-morbidity index were associated with readmission. ConclusionsOur surgical readmission rate was lower than previously reported rates in gynecologic oncology patients. Patient factors associated with readmission included younger age, longer index hospital admission, and higher medical co-morbidity index scores. Provider factors and institutional practice patterns could contribute to the decreased readmission rate. These findings underscore the importance of standardizing how we calculate readmission rate and interpret these data. Varying readmission rates and institutional practice patterns deserve closer scrutiny to inform best practice and future policies.

Association of Weight Trajectory With Severe Obesity: A Case-Control Study.

Background: Early childhood weight trajectory is associated with future risk for obesity. However, little is known about the association of birth weight and weight trajectories before age 5.5 years with severe adult obesity. Methods: This study used a nested case-control design of 785 matched sets of cases and controls matched 1:1 on age and gender from a 1976 to 1982 birth cohort in Olmsted County, Minnesota. Cases with severe adult obesity were defined as individuals with a BMI ≥40 kg/m2 after 18 years of age. There were 737 matched sets of cases and controls for the trajectory analysis. Weight and height data from birth through 5.5 years were abstracted from the medical records, and weight-for-age percentiles were obtained from the CDC growth charts. Results: A two-cluster weight-for-age trajectory solution was identified as optimal, with cluster 1 having higher weight-for-age before age 5.5 years. While there was no association between birth weight and severe adult obesity, the odds of being in cluster 1, which includes children with higher weight-for-age percentiles, was significantly increased for cases compared with controls [odds ratio (OR) 1.99, 95% confidence interval (CI) 1.60-2.47]. The association between cluster membership and case-control status persisted after adjusting for maternal age and education (adjusted OR 2.08, 95% CI 1.66-2.61). Conclusions: Our data suggest that early childhood weight-for-age trajectories are associated with severe obesity status in adult life. Our results add to growing evidence that it is critical to prevent excess early childhood weight gain.

Risk Factors for Cytomegalovirus Infection and Its Impact on Survival after Living Donor Liver Transplantation in South Korea: A Nested Case-Control Study.

Cytomegalovirus (CMV), a common pathogen, causes infectious complications and affects long-term survival after transplantation. Studies examining living donor liver transplantation (LDLT) are limited. This study analyzed the risk factors for CMV infection and its impact on the survival of LDLT patients. A nested case-control design retrospectively analyzed data from 952 patients who underwent LDLT from 2005-2021. The incidence of CMV infection for the study cohort was 15.2% at 3 months for LDLT patients managed preemptively. Patients with CMV infections were matched with those without the infection at corresponding time points (index postoperative day) in a 1:2 ratio. Graft survival was significantly lower in the CMV infection group than in the control group. CMV infection was an independent risk factor for graft survival in the matched cohort (HR 1.93, p = 0.012). Independent risk factors for CMV infection were female sex (HR 2.4, p = 0.003), pretransplant MELD (HR 1.06, p = 0.004), pretransplant in-hospital stay (HR 1.83, p = 0.030), ABO incompatibility (HR 2.10, p = 0.009), donor macrovesicular steatosis ≥10% (HR 2.01, p = 0.030), and re-operation before index POD (HR 2.51, p = 0.035). CMV infection is an independent survival risk factor, and its risk factors should be included in the surveillance and treatment of CMV infections after LDLT.

Incidence, mortality, and risk factors associated with carbapenem-resistant Acinetobacter baumannii bacteremia within 30 days after liver transplantation.

Carbapenem-resistant Acinetobacter baumannii bacteremia (CRAB-B) is a fatal infectious complication of liver transplantation (LT). This study investigated the incidence, effects, and risk factors associated with CRAB-B during the early post-LT period. Among 1051 eligible LT recipients, 29 patients experienced CRAB-B within 30 days of LT with a cumulative incidence of 2.7%. In the patients with CRAB-B (n=29) and matched controls (n=145) by nested-case control design, the cumulative incidence of death on days 5, 10, and 30 from the index date was 58.6%, 65.5%, and 65.5%, and 2.1%, 2.8%, and 4.2%, respectively (p<.001). Pre-transplant MELD (OR 1.11, 95% confidence interval [CI] 1.04-1.19, p=.002), severe encephalopathy (OR 4.62, 95% CI 1.24-18.61, p=.025), donor body mass index (OR .57, 95% CI .41-.75, p<.001), and reoperation (OR 6.40, 95% CI 1.19-36.82, p=.032) were independent risk factors for 30-day CRAB-B. CRAB-B showed extremely high mortality within 30 days after LT, especially within 5 days after its occurrence. Therefore, assessment of risk factors and early detection of CRAB, followed by proper treatment, are necessary to control CRAB-B after LT.

Comparison of cohort and nested case-control designs for estimating the effect of time-varying drug exposure on the risk of adverse event in the presence of ties.

Cohort and nested case-control (NCC) designs are frequently used in pharmacoepidemiology to assess the associations of drug exposure that can vary over time with the risk of an adverse event. Although it is typically expected that estimates from NCC analyses are similar to those from the full cohort analysis, with moderate loss of precision, only few studies have actually compared their respective performance for estimating the effects of time-varying exposures (TVE). We used simulations to compare the properties of the resulting estimators of these designs for both time-invariant exposure and TVE. We varied exposure prevalence, proportion of subjects experiencing the event, hazard ratio, and control-to-case ratio and considered matching on confounders. Using both designs, we also estimated the real-world associations of time-invariant ever use of menopausal hormone therapy (MHT) at baseline and updated, time-varying MHT use with breast cancer incidence. In all simulated scenarios, the cohort-based estimates had small relative bias and greater precision than the NCC design. NCC estimates displayed bias to the null that decreased with a greater number of controls per case. This bias markedly increased with higher proportion of events. Bias was seen with Breslow's and Efron's approximations for handling tied event times but was greatly reduced with the exact method or when NCC analyses were matched on confounders. When analyzing the MHT-breast cancer association, differences between the two designs were consistent with simulated data. Once ties were taken correctly into account, NCC estimates were very similar to those of the full cohort analysis.

Safety and effectiveness of rivaroxaban for prevention of stroke in patients with nonvalvular atrial fibrillation: analysis of routine clinical data from four countries

ABSTRACT Background The safety and effectiveness of rivaroxaban versus vitamin K antagonists (standard of care [SOC]) for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF) was evaluated in Europe. Research design and methods Observational studies were conducted in the UK, the Netherlands, Germany, and Sweden. Primary safety outcomes were hospitalization for intracranial hemorrhage, gastrointestinal bleeding, or urogenital bleeding among new users of rivaroxaban and SOC with NVAF; outcomes were analyzed using cohort (rivaroxaban or SOC use) and nested case–control designs (current vs nonuse). Statistical analyses comparing rivaroxaban and SOC cohorts were not performed. Results Overall, 162,919 rivaroxaban users and 177,758 SOC users were identified. In the cohort analysis, incidence ranges for rivaroxaban users were 0.25–0.63 events per 100 person-years for intracranial bleeding, 0.49–1.72 for gastrointestinal bleeding, and 0.27–0.54 for urogenital bleeding. Corresponding ranges for SOC users were 0.30–0.80, 0.30–1.42, and 0.24–0.42, respectively. In the nested case–control analysis, current SOC use generally presented a greater risk of bleeding outcomes than nonuse. Rivaroxaban use (vs nonuse) was associated with a higher risk of gastrointestinal bleeding, but a similar risk of intracranial or urogenital bleeding, in most countries. Ischemic stroke incidence ranged from 0.31 to 1.52 events per 100 person-years for rivaroxaban users. Conclusions Incidences of intracranial bleeding were generally lower with rivaroxaban than with SOC, whereas incidences of gastrointestinal and urogenital bleeding were generally higher. The safety profile of rivaroxaban for NVAF in routine practice is consistent with findings from randomized controlled trials and other studies.

Development and validation of a prediction model for intrapartum cesarean delivery based on the artificial neural networks approach: a protocol for a prospective nested case–control study

IntroductionAlthough intrapartum caesarean delivery can resolve dystocia, it would still lead to several adverse outcomes for mothers and children. The obstetric care professionals need effective tools that can help them...

Analysis and asymptotic theory for nested case-control designs under highly stratified proportional hazards models.

Nested case-control sampled event time data under a highly stratified proportional hazards model, in which the number of strata increases proportional to sample size, is described and analyzed. The data can be characterized as stratified sampling from the event time risk sets and the analysis approach of Borgan et al.(Ann Stat 23:1749-1778, 1995) is adapted to accommodate both the stratification and case-control sampling from the stratified risk sets. Conditions for the consistency and asymptotic normality of the maximum partial likelihood estimator are provided and the results are used to compare the efficiency of the stratified analysis to an unstratified analysis when the baseline hazards can be semi-parametrically modeled in two special cases. Using the stratified sampling representation of the stratified analysis, methods for absolute risk estimation described by Borgan et al.(1995) for nested case-control data are used to develop methods for absolute risk estimation under the stratified model. The methods are illustrated by a year of birth stratified analysis of radon exposure and lung cancer mortality in a cohort of uranium miners from the Colorado Plateau.

Incidence and risk factors of surgical site infections after coronary artery bypass grafting surgery in Oman.

There is limited information about the incidence and risk factors of surgical site infections (SSIs) after coronary artery bypass (CABG) surgeries in the Omani population. To estimate the prevalence and describe possible risk factors of SSIs after CABG surgeries in Oman. A retrospective nested case-control design was used to screen 596 patients who underwent CABG surgeries over 2years (2016-2017) in two tertiary hospitals in Oman. The CDC definition for SSIs was used to identify the infected cases. Prevalence rate of SSIs was 17.4% and 17.5% in 2016 and 2017, respectively. The most isolated microorganism was Gram-positive bacteria (45.2%). Risk factors of SSIs include female gender (OR = 3.2, p < 0.001), diabetes (OR = 5.83, p < 0.001), overweight or obese (OR = 2.14, p < 0.05) and shaving technique [using razor shaving] (OR = 8.4, p < 0.001). Readmission rate for the case group was 44.2%. The infection rate of SSIs after CABG surgeries in developing countries, such as Oman, is considerably high. There is an urgent need to establish SSIs preventive program at the national level. Frequent and systematic assessment of infection control practices before and after CABG surgeries is fundamental and priority strategy to prevent SSIs.

Daily monitoring of diabetic treatment amongst TB-DM patients under NTEP: Does it improve the treatment outcomes?

Problem consideredDirectly Observed Treatment (DOT) has been the cornerstone for favorable outcomes in Tuberculosis treatment. Hitherto, the role of Diabetic DOT for TB-DM patients has not been explored in the present times when TB-DM dual epidemic has grown by significant proportions. The study aims to know the treatment outcomes in TB-DM patients under programmatic settings with or without DM treatment supervision and also to assess the concurrent glycemic control during the course of TB treatment. MethodsIn this cohort study with nested case control design, total 102 TB-DM patients registered under National TB Elimination Programme of District Dakshina Kannada from July 2017 to March 2019 were enrolled. Systematic Diabetic Treatment monitoring was done in one geographical area whereas in other areas the monitoring was not done. Socio-clinico-demographic variables including glycemic control were analyzed. ResultsThe results showed that the treatment success rate was 92% in both intervention and non-intervention geographical areas. There was no association between the favorable TB treatment outcome amongst the TB DM patients and their demographic variables. A two-way repeated measure ANOVA with a Greenhouse Giesser correction determined that the mean value of HbA1c was statistically significant between assessment stages during the course of treatment and the interaction HbA1c and supervision arm had a significant effect. ConclusionDiabetic DOT led to relatively better glycemic control (HbA1c) in TB-DM patients although in programmatic management of TB-DM patients, it did not have any significant effect on the TB treatment outcomes.

Early risk assessment in paediatric and adult household contacts of confirmed tuberculosis cases by novel diagnostic tests (ERASE-TB): protocol for a prospective, non-interventional, longitudinal, multicountry cohort study

IntroductionThe WHO End-TB Strategy calls for the development of novel diagnostics to detect tuberculosis (TB) earlier and more accurately. Better diagnostics, together with tools to predict disease progression, are critical...