Matched Case-control Study Research Articles

Evaluating risk factors for development of a parastomal hernia: a retrospective matched case-control study

Evaluating risk factors for development of a parastomal hernia: a retrospective matched case-control study

Coxa valga and antetorta configuration leads to underestimation of the femoral component size: a matched case-control study of patients undergoing cementless total hip arthroplasty.

Total hip arthroplasty (THA) is the gold standard procedure for patients with end-stage osteoarthritis after failed conservative therapy. Digital templating is commonly employed in preoperative preparation for THA and contributes positively to its outcome. However, the impact of coxa valga and antetorta (CVA) configurations on stem size prediction accuracy remains not reported. Previous studies demonstrated that the size of the lesser trochanter (LT) can be used to determine femoral anteversion on pelvis radiographs. This study investigates the accuracy of preoperative digital templating in predicting stem size in patients with CVA undergoing cementless THA. Preoperative radiographs of 620 patients undergoing cementless THA were retrospectively investigated. Radiographs were standardized with patients standing and the leg internally rotated by 15°. A CVA group was established including patients with a CCD angle greater than 140° and a lesser trochanter (LT) size of at least 10mm for men and 8mm for women. For the control group, radiographs with a CCD angle ranging from 125-135° and LT size 3-10mm for men and 3-8mm for women were selected. Preoperative templating was performed using mediCAD. To reduce confounding factors, case-control matching was carried out for BMI and body height. After case-control matching, a total of thirty-one matches were analyzed. Stem size was underestimated in 74% (23/31) in the CVA and 13% (4/31) in the control group (p < 0.001). Moreover, patients with CVA were more likely to be underestimated by two sizes compared to controls (p < 0.004). In contrast, the exact stem size was predicted more frequently in the control group (p < 0.001). Stem size in patients with a CVA configuration are at high risk of being underestimated when using digital templating. These findings can be valuable for guiding in intraoperative decisions and lowering the risk of complications associated with an undersized femoral component.

Comprehensive analysis of adverse events associated with transmural use of LAMS in patients with liver cirrhosis: International multicenter study

Abstract Background and study aims Endoscopic ultrasound (EUS)-guided transmural (TM) deployment of lumen-apposing metal stents (LAMS) is considered relatively safe in non-cirrhotic patients and is cautiously offered to cirrhotic patients. Patients and methods This was a retrospective, multicenter, international matched case-control study to study the safety of EUS-guided TM deployment of LAMS in cirrhotic patients. Results Forty-three cirrhotic patients with model for end-stage liver disease score 12.5 ± 5, with 23 having ascites and 16 with varices underwent EUS-guided TM LAMS deployment, including 19 for pancreatic fluid collection (PFC) drainage, 13 gallbladder drainage, six for endoscopic ultrasound-directed transgastric endoscopic retrograde cholangiopancreatography (ERCP), three for EDGI, one for endoscopic ultrasound-directed transenteric ERCP, and one postsurgical collection drainage. Technical failure occurred in one LAMS for PFC drainage. Clinical failure was encountered in another PFC. Nine adverse events (AEs) occurred. The most common AE was LAMS migration (3), followed by non-bleeding mucosal erosion (2), delayed bleeding (2), sepsis (1), and anesthesia-related complication (pulseless electrical activity) (1). Most AEs were graded as mild (6), followed by severe (2), and moderate (1); the majority were managed conservatively. On univariable comparison, risk of AE was higher when using a 20 × 10 mm LAMS and the absence of through-the-LAMS plastic stent(s). Conditional logistic regression of matched case-control patients did not show any association between potential predicting factors and occurrence of AEs. Conclusions Our study demonstrated that mainly in patients with Child-Pugh scores A and B cirrhosis and despite the presence of mild-to-moderate ascites in over half of cases, the majority of AEs were mild and could be managed conservatively. Further studies are warranted to verify the safety of LAMS in cirrhotic patients.

Comparison of early visual outcomes after SMILE using VISUMAX 800 and VISUMAX 500 for myopia: a retrospective matched case–control study

VISUMAX 800 was introduced to improve the patient experience and clinical outcomes of small incision lenticule extraction (SMILE). This was a retrospective, matched, and case–control study (1:2) controlled for preoperative central corneal thickness and refractive error that compared early refractive and visual outcomes after SMILE using VISUMAX 800 and VISUMAX 500 to treat myopia. We included 50 eyes that underwent the VISUMAX 800 SMILE and 100 eyes that underwent the VISUMAX 500 SMILE. SMILE using VISUMAX 800 was performed using the CentraLign aid for vertex centration. Cyclotorsion was controlled by an OcuLign assistant in the VISUMAX 800 group after corneal marking. Corneal higher-order aberrations (HOAs) were evaluated using a Pentacam 1 month after surgery. No differences were observed in the pre- and post-operative refractive and visual outcomes at 1 day, 1 month, and 6 months after surgery. VISUMAX 800 induced less total HOAs than VISUMAX 500 (P = 0.036). No statistically significant differences were observed in the amounts of induced spherical aberrations or vertical and horizontal comas. No differences were observed in the 1 month and 6 months refractive and visual outcomes between two SMILE procedures, except for VISUMAX 800, which resulted in lower postoperative total HOAs than VISUMAX 500.

#1149 Long-COVID in hemodialysis patients: a matched case-control prospective study

Abstract Background and Aims Long-COVID is defined as persistent symptoms after COVID-19 infection. It has been reported that up to 40% of COVID-19 survivors experience long-COVID (O'Mahoney et al. The Lancet, 2023). We aim to determine if hemodialysis (HD) patients experience long-COVID. Method HD patients diagnosed with COVID-19 via RT-PCR test were enrolled from January to April 2022 from 4 clinics in New York City. COVID-19 Yorkshire Rehabilitation Scale (C19-YRS) was administered at baseline (i.e., as soon as possible after diagnosis), and 1 and 6 months after baseline. C19-YRS measures symptoms such as dyspnea, fatigue, decreased cognition, etc. before and after COVID-19 infection. Pre-COVID symptom severity at baseline was used as the comparator when determining differences between pre- and post-COVID periods. Controls were also enrolled as symptoms resembling long-COVID symptoms are prevalent in HD patients who did not have COVID-19 (e.g., fatigue, lowered quality of life, cognitive impairment). Controls were matched to case patients by age (&amp;lt;50 years, 50-70 years, &amp;gt;70 years), vintage (&amp;lt;1 year, 1-5 years, &amp;gt;5 years), sex, and race. In control patients, a modified C19-YRS that excluded questions specifically around COVID-19 infection was administered at the time of enrollment, and 1 and 6 months thereafter. Symptom severity is graded from 0-10 (10 being the worst) and global health score is reported with 10 being the best. Patient demographic and clinical data were obtained from medical records. Paired t-tests tests were used to examine differences in symptom severity pre- and post-COVID-19 infection in case patients. Unpaired t-tests or Chi-squared tests were used to examine differences at each time point in cases and controls. Linear and generalized mixed models were used to examine the effect of time on continuous and discrete long-COVID symptom severity, respectively. Results We studied 30 patients, 15 cases and 15 controls. There were no significant differences between the two groups in age, vintage, sex, race, ethnicity, diabetes, or hypertension (Table 1a). Baseline C19-YRS was administered 43 ± 24 days (range 9-108) after COVID-19 diagnosis. Five patients were hospitalized because of COVID-19 infection. C19-YRS results are shown in Table 1b. Compared to the pre-COVID period, case patients experienced significantly increased dyspnea at baseline; anxiety, depression, and dyspnea at 1 month; fatigue and dyspnea at 6 months. Further, fatigue and ability to perform personal care worsened in case patients from baseline to 6 months. Compared to the cases, controls had significantly higher global health scores at 1 month and a lower prevalence of dyspnea at rest and fatigue at 6 months. Conclusion Following COVID-19 infection, patients report worsening long-COVID symptoms compared to (a) the pre-COVID period and (b) matched controls, specifically fatigue, dyspnea at rest, and decreased perceived health. Further studies are warranted to investigate the long-term consequences of long-COVID in HD patients.

Serum Microcystin-LR Levels Linked with Risk of Inflammatory Bowel Disease: A Matched Case-Control Study in China.

Microcystin-LR (MC-LR), the most prevalent and diverse cyanotoxin produced by harmful cyanobacterial blooms, has been linked to gastrointestinal toxicity. Therefore, we conducted a case-control study across four regions in China to investigate this relationship. Inflammatory bowel disease (IBD) cases (219) were matched with healthy controls (438) based on age and gender and conditional logistic regression models and Restricted cubic splines were used to evaluate the association between MC-LR exposure and IBD risk. We used quantitative real-time polymerase chain reaction to measure the expression levels of inflammatory factors. The levels of protein expression in the colorectum were determined using Western blotting (WB). Compared to the lowest quartile of serum MC-LR levels, the adjusted odds ratios and 95% confidence intervals (CI) for the highest quartiles of serum MC-LR levels were 5.51 (2.70, 11.21). The RCS was shown the association between serum MC-LR levels and IBD risk was nonlinear (P nonlinear < 0.001). In the animal experiments, MC-LR resulted in colorectal injury via the PI3K/AKT signaling pathway. Our study provides the evidence that serum MC-LR exposure is significantly associated with the risk of IBD in China. Animal study results indicate that MC-LR probably causes IBD via the PI3K/AKT signaling pathway.

Evaluation of a Tube Voltage-Based Contrast Media Adaptation in Coronary Computed Tomography Angiography Using Personalized Triphasic Injection Protocols: A Matched Case-Control Study

Rationale and ObjectivesCoronary CT angiography (CCTA) has recently been established as a first line test in patients with suspected coronary artery disease (CAD). Due to the increased use of CCTA, strategies to reduce radiation and contrast medium (CM) exposure is of high importance. The aim of this study was to evaluate the performance of automated tube voltage selection (ATVS)-adapted CM injection protocol for CCTA compared to a clinically established triphasic injection protocol in terms of image quality, radiation exposure, and CM administration Material and MethodsPatients undergoing clinically indicated CCTA were prospectively enrolled from July 2021 to July 2023. Patients underwent CCTA using a modified triphasic CM injection protocol tailored to the tube voltage by the ATVS algorithm, in a range of 70 to 130kV with a 10kV interval. The injection protocol consisted of two phases of mixed CM and saline boluses with different proportions to assure a voltage-specific iodine delivery rate, followed by a third phase of saline flush. This cohort was compared to a control group identified retrospectively and scanned on the same CT system but with a standard triphasic CM protocol. Radiation and contrast dose, subjective and objective image quality (contrast-to-noise-ratio [CNR] and signal-to-noise-ratio [SNR]) were compared between the two groups. ResultsThe final population consisted of 120 prospective patients matched with 120 retrospective controls, with 20 patients in each kV group. The 120kV group was excluded from the statistical analysis due to insufficient sample size. A significant CM reduction was achieved in the prospective group overall (46.0 [IQR 37.0-52.0] vs. 51.3 [IQR 40.1-73.0] ml, p<0.001) and at all kV levels too (all pairwise p<0.001). There were no significant differences in radiation dose (6.13 ± 4.88 vs. 5.97 ± 5.51 mSv, p=0.81), subjective image quality (median score of 4 [3–5] vs 4 [3–5], p=0.40), CNR, and SNR in the aorta and the left anterior descending coronary artery (all p>0.05). ConclusionATVS-adapted CM injection protocol allows for diagnostic quality CCTA with reduced CM volume while maintaining similar radiation exposure, subjective and objective image quality.

Determinants of second-dose measles vaccination dropout in Ethiopia: A community-based matched case-control study

BackgroundMeasles vaccination is the most important public health intervention and a cost-effective strategy to reduce morbidity and mortality in under-five children. Although Ethiopia's government developed a measles elimination strategic plan by 2020, the full coverage of immunization was 43 %. Therefore, this study aimed to identify determinants of second-dose measles vaccination (MCV2) dropout among children aged 24–35 months in East Bale Zone, Ethiopia. MethodA community-based matched case-control study was conducted among 351 children (117 cases and 234 controls). Children who received the first dose of measles vaccine but did not receive the second dose were cases, and children who received both doses of measles vaccine were control. The matches were based on age and residence. The data were collected using a structured questionnaire, entered into Epi Data 3.1, cleaned, exported, and analyzed using Stata version 16.1. A multivariable conditional logistic regression analysis was performed. Variables with a P value of <0.05 were considered significant determinants of the dependent variable at the 95 % confidence level. ResultsMothers who were unable to read and write (mAOR: 4.0; 95 % CI: 1.59–10.2), did not receive counseling (mAOR: 3.19; 95 % CI: 1.62–6.27), spent ≥30 min to reach health facilities (mAOR; 2.76, 95 % CI: 1.25–6.1), and did not attend postnatal care (mAOR; 3.46, 95 % CI: 1.58–7.57) were significantly and positively associated with second-dose measles vaccination dropout. In addition, mothers who had poor knowledge of second-dose measles vaccination (mAOR; 3.20, 95 % CI: 1.50–6.70) and waited more than an hour for measles vaccination at health facilities (mAOR; 2.61, 95 % CI: 1.0–6.20) were significantly more likely to experience second-dose measles vaccine dropout. ConclusionsThe key factors associated with second-dose measles vaccination dropout are maternal illiteracy, lack of PNC, inadequate maternal knowledge and poor counseling about MCV2 vaccination, long distances travel to healthcare facilities and extended waiting times at vaccination providing sites. Health extension workers emphasize strengthening home visit programs in catchment households to improve mothers' awareness of measles vaccination.

Variations in the sleep-related breathing disorder index on polysomnography between men with HIV and controls: a matched case-control study

BackgroundBoth sleep-related breathing disorders (SRBDs) and HIV infection can interfere with normal sleep architecture, and also cause physical and psychological distress. We aimed to understand the differences in the obstructive patterns, sleep architecture, physical and psychological distress when compared between people living with HIV (PLWH) and matched the severity of SRBDs controls.MethodsA comparative study using matched case-control design was conducted. Men with HIV infection (case group) were enrolled from 2016 to 2019. A control group with HIV seronegative men were matched for SRBDs severity, and were selected from sleep medicine center database for comparison.ResultsThe mean age of the 108 men (including 54 cases and 54 matched controls) was 33.75 years. Central-apnea index (CI) was higher in the case group rather than matched controls (mean CI, 0.34 vs. 0.17, p = 0.049). PLWH had a lower mean percentage of stage 3 sleep (10.26% vs. 13.94%, p = 0.034) and a higher percentage of rapid eye movement sleep (20.59% vs. 17.85%, p = 0.011) compared to matched controls. Nocturnal enuresis and sleepiness causing traffic accidents were more frequent complaint in PLWH compared to controls.ConclusionsEarly detected SRBDs and subtypes in PLWH to begin treatment for the underlying cause could reduce the risk of sleepiness-related traffic accidents.

What is the significance of trunk muscle morphology in terms of balance? Structure vs function in chronic post-stroke patients. A cross-sectional study

Objective: To assess the architecture of the trunk muscles with RUSI and to reveal which parameters may be related to balance assessment tools in patients that suffered a stroke with hemiparesis. Methods: An observational, analytical, cross-sectional, matched case-control study was conducted, nested within a single-center cohort comprising patients with chronic hemiparesis. Twenty individuals in the chronic post-stroke stage and twenty healthy controls were recruited for this investigation. Key outcomes included the thickness measurements of the Rectus Abdominis (RA), External Oblique (OE), Internal Oblique (OI), Transversus Abdominis (TrAb), and Lumbar Multifidus (LMult) muscles, as well as assessments using the Modified Rivermead Functional Test (MRFT), Timed Up and Go (TUG), and BERG scales. Results: Results did not show statistically significant differences between groups for the outcomes measured. Conclusions: The findings indicate no significant disparities between the measured sides, suggesting that muscle alterations in patients that suffered a stroke may be more pronounced during the acute stage compared to the chronic stage. Keywords: Stroke, trunk, balance.

Identifying and characterizing high-risk populations in pilot malaria elimination districts in Madagascar: a mixed-methods study

BackgroundIn Madagascar, the districts of Antsirabe II, Faratsiho and Antsiranana I have relatively low malaria incidence rates and have been selected by the National Malaria Control Programme for pilot elimination strategies. The districts have residual transmission despite increasing coverage and quality of malaria services. This study sought to identify priority subpopulations at highest risk for malaria and collect information on intervention preferences and methods that will inform subnational tailoring of malaria service delivery.MethodsThis mixed methods study employed (i) a quantitative malaria risk factor assessment in Antsirabe II and Faratsiho comprising a test-negative frequency matched case–control study and a qualitative risk factor assessment in Antsiranana I; and (ii) a qualitative formative assessment in all three districts. For the case–control study, a mixed effects logistic regression was used with age, sex and district included as fixed effects and health facility included as a random effect. The qualitative risk factor assessment used semi-structured interview guides and key informant interviews. For the qualitative formative assessment in the three districts, a summary report was generated following semi-structured interviews and focus group discussions with high-risk populations (HRPs) and stakeholders.ResultsIn Antsirabe II and Faratsiho districts, rice agriculture workers, outdoor/manual workers, particularly miners, and those with jobs that required travel or overnight stays, especially itinerant vendors, had higher odds of malaria infection compared to other (non-rice) agricultural workers. In Antsiranana I, respondents identified non-rice farmers, mobile vendors, and students as HRPs. Risk factors among these groups included overnight stays and travel patterns combined with a lack of malaria prevention tools. HRPs reported treatment cost and distance to the health facility as barriers to care and expressed interest in presumptive treatment and involvement of gatekeepers or people who have influence over intervention access or participation.ConclusionsThe study results illustrate the value of in-depth assessments of risk behaviours, access to services and prevention tools, surveillance and prevention strategies, and the involvement of gatekeepers in shaping subnational tailoring to reach previously unreached populations and address residual transmission in elimination settings.

Short-Term Medication Effect on Fall Risk in Multimorbid Inpatients with Dementia

Introduction: Dementia increases the risk of falls and fall-related injuries, which may be caused by inappropriate medication use. To date, there is little evidence on which medications are more likely to cause falls. We therefore investigated the effects of medication use and medication changes 48 h before falls in hospitalised patients with dementia. Methods: This matched case-control study included 74 patients with a mean age of 83 years (38% women) who had been hospitalised for at least 7 days. Information on medications, diagnoses, disease severity, use of walking aids, falls, and demographics was collected from electronic medical records. The effects of the number of medications and psychotropics, equivalent daily doses of antidepressants, antipsychotics and benzodiazepines, anticholinergic burden, medication initiation, dose change, medication discontinuation, as-needed medications, opioid use and the presence of fall-increasing diseases were examined separately for the periods 0 h–24 h and 24 h–48 h before the falls using binomial logistic regression analyses. Results: Falls increased significantly with higher daily antipsychotic doses 24 h before the fall. In addition, the rate of falls increased with higher anticholinergic burden and prevalence of medication discontinuation 24–48 h before the fall. Notably, the total number of medications and psychotropic medications had no effect on the incidence of falls. Conclusion: With regard to the short-term effects of medication on fall risk, particular attention should be paid to the daily dose of antipsychotics, anticholinergic burden and medication discontinuation. Further studies with larger samples are needed to confirm the results of this study.

Risk Factors for and Outcomes Following Early Acquisition of Mycobacterium abscessus Complex After Lung Transplantation.

Lung transplant recipients are at increased risk of Mycobacterium abscessus complex (MABC) acquisition and invasive infection. We analyzed risk factors and outcomes of early post-lung transplant MABC acquisition. We conducted a retrospective matched case-control study of patients who underwent lung transplant from 1/1/2012 to 12/31/2021 at a single large tertiary care facility. Cases had de novo MABC isolation within 90 days post-transplant. Controls had no positive MABC cultures and were matched 3:1 with cases based on age and transplant date. Recipient demographics and pre-/peri-operative characteristics were analyzed, and a regression model was used to determine independent risk factors for MABC acquisition. We also assessed 1-year post-transplant outcomes, including mortality. Among 1145 lung transplants, we identified 79 cases and 237 matched controls. Post-transplant mechanical ventilation for >48 hours was independently associated with MABC acquisition (adjusted odds ratio, 2.46; 95% CI, 1.29-4.72; P = .007). Compared with controls, cases required more days of hospitalization after the MABC index date (28 vs 12 days; P = .01) and had decreased 1-year post-transplant survival (78% vs 89%; log-rank P = .02). One-year mortality appeared highest for cases who acquired M. abscessus subsp. abscessus (31% mortality) or had extrapulmonary infections (43% mortality). In this large case-control study, prolonged post-transplant ventilator duration was associated with early post-lung transplant MABC acquisition, which in turn was associated with increased hospital-days and mortality. Further studies are needed to determine the best strategies for MABC prevention, surveillance, and management.

Genome-wide 5-hydroxymethylcytosines in circulating cell-free DNA as noninvasive diagnostic markers for gastric cancer.

5-Hydroxymethylcytosine-enriched gene profiles and regions show tissue-specific and tumor specific. There is a potential value to explore cell-free DNA 5-hydroxymethylcytosine feature biomarkers for early gastric cancer detection. A matched case‒control study design with 50 gastric cancer patients and 50 controls was performed to sequence the different 5-hydroxymethylcytosine modification features of cell free DNA. Significantly differential 5-hydroxymethylcytosine modification genes were identified to construct a gastric cancer diagnostic model. Data set from GEO was used as an external testing set to test the robustness of the diagnostic model. Accounting for more than 90% of 5-hydroxymethylcytosine peaks were distributed in the gene body in both the gastric cancer and control groups. The diagnostic model was developed based on five different 5-hydroxymethylcytosine modification genes, FBXL7, PDE3A, TPO, SNTG2 and STXBP5. The model could effectively distinguish gastric cancer patients from controls in the training (AUC = 0.95, sensitivity = 88.6%, specificity = 94.3%), validation (AUC = 0.87, sensitivity = 73.3%, specificity = 93.3%) and testing (AUC = 0.90, sensitivity = 81.9%, specificity = 90.2%) sets. The risk scores of the controls from the model were significantly lower than those of gastric cancer patients in bothour own data (P < 0.001) and GEO external testing data (P < 0.001), and no significant difference between different TNM stage patients (P = 0.09 and 0.66). Furthermore, there was no significant difference between the healthy control and benign gastric disease patients in the testing set from GEO (P = 0.10). The characteristics of 5-hydroxymethylcytosine in cell free DNA are specific to gastric cancer patients, and the diagnostic model constructed by five genes' 5-hydroxymethylcytosine features could effectively identify gastric cancer patients.

Evaluation of three-year neurodevelopmental outcomes in infants prenatally exposed to substance use

IntroductionPrenatal exposure to substance use is associated with long-term deficits in the neurodevelopment of children. The objective was to investigate the association between cognitive, motor, and language neurodevelopment at three years of age in infants prenatally exposed to substance use. Material and methodsA prospective matched case-control study was conducted. Biomarkers of fetal exposure were measured in meconium samples. The Bayley Scales of Infant and Toddler Development (BSID-III) were used to calculate neurodevelopment scores. Results32 non-exposed and 32 exposed infants were evaluated, of which 16 were exposed to cannabis, 8 to ethanol, 2 to cocaine and 6 to more than one substance. Normal BSID-III scores ≥85 in all domains, were detected in 23 exposed infants to any substance and 29 infants non-exposed. Neurodevelopmental delay was detected in the language domain, specifically in male infants exposed to cannabis. Two infants exposed to cannabis had a severe developmental delay (score<70). Infants exposed to any substance obtained significantly lower total scores than control infants in all domains. Infants exposed to cannabis obtained significantly lower composite scores in the cognitive and motor domains. Infants exposed to more than one substance had lower scores in motor skills. By gender, only males exposed obtained significantly lower composite scores than non-exposed males in the cognitive domain. ConclusionsThe most common and severe neurodevelopmental delay at 36 months was detected in the domain of language in male infants prenatally exposed to cannabis. Neurodevelopmental disorders detected can enable an early intervention and plan therapeutic strategies.

Associations of neighborhood greenspace, and active living environments with autism spectrum disorders: A matched case-control study in Ontario, Canada

BackgroundIncreasing evidence links early life residential exposure to natural urban environmental attributes and positive health outcomes in children. However, few studies have focused on their protective effects on the risk of autism spectrum disorder (ASD). The aim of this study was to investigate the associations of neighborhood greenspace, and active living environments during pregnancy with ASD in young children (≤6 years). MethodsWe conducted a population-based matched case-control study of singleton term births in Ontario, Canada for 2012–2016. The ASD and environmental data was generated using the Ontario Autism Spectrum Profile, the Better Outcomes Registry & Network Ontario, and Canadian Urban Environmental Health Research Consortium. We employed conditional logistic regressions to estimate the odds ratio (OR) between ASD and environmental factors characterizing selected greenspace metrics and neighborhoods conducive to active living (i.e., green view index (GVI), normalized difference vegetation index (NDVI), tree canopy, park proximity and active living environments index (ALE)). ResultsWe linked 8643 mother-child pairs, including 1554 cases (18%). NDVI (OR 1.034, 0.944–1.024, per Inter Quartile Range [IQR] = 0.08), GVI (OR 1.025, 95% CI 0.953–1.087, per IQR = 9.45%), tree canopy (OR 0.992, 95% CI 0.903–1.089, per IQR = 6.24%) and the different categories of ALE were not associated with ASD in adjusted models for air pollution. In contrast, living closer to a park was protective (OR 0.888, 0.833–0.948, per 0.06 increase in park proximity index), when adjusted for air pollution. ConclusionsThis study reported mixed findings showing both null and beneficial effects of green spaces and active living environments on ASD. Further investigations are warranted to elucidate the role of exposure to greenspaces and active living environments on the development of ASD.

IJCM_180A: Risk factors for hemorrhoids among patients attending selected tertiary care hospitals in Mangalore: A matched case control study

Background: Hemorrhoids is a common anorectal condition affecting a vast majority of population all around the world. The establishment of a definite association of hemorrhoids with bowel habits and other factors like BMI is less explored. Objectives: To find out the association of hemorrhoids especially with bowel habits and to establish the association of BMI with respect to the onset of hemorrhoids. Methodology: This case control study was conducted among 90 cases and controls from the hospitals affiliated to Kasturba Medical college, Mangalore. Data were analyzed using SPSS version 29. Uni-variate analysis was done, and the odds ratio and confidence levels were tested and determined using binary logistic regression. Results: Majority of the controls were normal with respect to BMI categorization (36.8%) whereas 34.9% of the cases were obese (p=0.095) . The number of people who consumed mixed diet was greater in the cases (72.3%) than in the controls (64.4%). 61.5% of patients complained of blood in stools compared to 2.2% of controls, there were 10.5% of cases with pus in stools and none in controls (p=0.249). Use of laxatives was seen in 27.7% of cases and only 2.1% of controls (p=0.001). A total score of &gt;=15 was indicative of constipation. 12.8% showed constipation compared to none in the controls. (p=0.026). Conclusion: Association of constipation with hemorrhoids was statistically significant. The occurrence of hemorrhoids was not associated with the body mass index of the individual and the occurrence of diarrhea was not significant with respect to hemorrhoids.

54 Identifying Geographic Clusters of H. pylori Associated Metastatic Early-Onset Gastric Cancer: A case-control study in Los Angeles

OBJECTIVES/GOALS: More young adults (age &lt;50 years) are diagnosed with metastatic gastric cancer (mGC) every year. We will evaluate the association between environmental risk factors (including historical racial residential segregation) clinical, pathologic, molecular features and H.pylori associated early-onset mGC (mE-GC). METHODS/STUDY POPULATION: This retrospective matched case-control study of patients (1:2 by diagnosis year) with mGC (early-onset [E-GC; &lt;50 years]; vs older-onset [O-GC; &gt;50 years]) from 2000-2022 from the Los Angeles Cancer Surveillance Program (LA-CSP) will be enriched by a chart-abstracted cohort from USC Norris Comprehensive Cancer (NCCC). This annotated database captures sociodemographic, medical, and pathologic features of patients treated for mGC at NCCC. It will link to LA-CSP data exploring neighborhood features (obesity rate, poverty, insurance, access to care, ethnic enclave, historical segregation, etc.) of cases and controls to identify, characterize, and compare geographic “hotspot” neighborhoods of mE-GC. We hypothesize younger Hispanic and Asian patients are at higher risk of H.pylori associated mGC. RESULTS/ANTICIPATED RESULTS: From 2000-2022, 339 patients (mE-GC n = 113; mO-GC n=226) were treated at NCCC. We will have characterized clinical and pathological features of mE-GC vs mO-GC. We determined the proportion of H. pylori associated mE-GC vs mO-GC. We will have established the geographical distribution of patients with mE-GC vs mO-GC to identify high-risk neighborhoods. We will link neighborhood risk factors such as food scarcity, poverty, health care access, ethnic enclaves, to the distinct clinical and pathological features of mE-GC, including H. pylori status. Descriptive statistics, chi-square, t-tests, and multivariable regression will be used to compare mE-GC to mO-GC. After controlling for underlying demographics and tumor features, we anticipate clusters of mE-GC and mO-GC in areas of historical racial segregation. DISCUSSION/SIGNIFICANCE: Linking neighborhood and individual risk factors for mE-GC will inform early detection and prevention efforts for vulnerable individuals in high-risk neighborhoods. Building community partnerships within these neighborhoods is essential for developing interventions targeting H. pylori treatment to reduce health disparities in mE-GC.

Repeat Resection for Recurrent Glioblastoma in the WHO 2021 Era: A Prospective Matched Case-Control Study

INTRODUCTION: The role of resection for recurrent glioblastoma remains unclear. METHODS: Patients who underwent repeat resection for recurrent IDH-wild-type glioblastoma were prospectively matched with 1:1 control cohort (n = 30:30). The two groups signed the consent and were matched for age, gender, comorbidities, eloquent vs. non-eloquent location, preoperative tumor volume and extent of resection in first surgery, neuropathological features as in WHO 2021 classification, time to progression, tumor volume at the time of recurrence, Park Score, ventricular wall involvement, use of steroids or multiple antiseizure medications and adjuvant therapy. Primary aim was to evaluate the overall survival in two cohorts. The secondary aim was to determine predictive factors for long term survival after repeat resection. RESULTS: After matching, patients had a long term follow up until death. Median overall survival times for patients who underwent repeat and one resection was 23.8 months vs 9.1 months, respectively (Log-Rank p &lt; 0.001). Two predictive factors for long term survival after repeat resection were preoperative Karnofsky Performance Score &gt;70 and Glasgow Coma Scale &gt;13 (Fisher p = 0.07 and p &lt; 0.001, respectively) while age, time to surgery, preoperative volume, extend of resection in repeat resection, location of tumor, its extension to ventricular wall, ependymal enhancement, comorbidities, tumor histological and molecular features did not correlate with postoperative survival. CONCLUSIONS: This is the first prospective matched case-control study revealing survival benefit of repeat resection for recurrent gliomas with long term follow up in a select group.

Association of pharmacogenomic, clinical and behavioural factors with oral levothyroxine (LT-4) dose of hypothyroid patients in Sri Lanka: a matched case control study

BackgroundHypothyroidism is a common endocrine disorder that exerts a substantial influence on people all over the world. Levothyroxine (LT-4) is the drug of choice for the treatment of hypothyroidism and the starting oral dose is typically ranging from 1.5 to 1.7 µg/kg/day. The target is to achieve an optimum serum TSH level of 0.4-4.0 mIU/L; hence, the dose is titrated accordingly. Once the LT-4 dose is adjusted to obtain the target TSH level, it usually remains stable for a long period of time in most cases. However, some of the patients require frequent dose adjustments and some of them require unusually high doses. Therefore, the aim of this study is to determine the association of pharmacogenomic, clinical and behavioural factors with the oral levothyroxine (LT-4) dose requirement of hypothyroid patients in Sri Lanka.MethodThis study will be conducted as a matched case-control study and will involve primary hypothyroid patients who visit the diabetes and endocrinology clinic at the National Hospital, Kandy, Sri Lanka. We will recruit a total of 292 cases and select 292 controls from the clinic who are matched in terms of age, sex and Body Mass Index (BMI). An interviewer-administered questionnaire will be used to collect data from the participants (n = 584). Of the 584 patients, blood samples will be collected from a sub-sample (n = 150) for DNA extraction. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) will be performed for single nucleotide polymorphisms (SNP) analysis.DiscussionFrequent dose adjustments of levothyroxine cause a serious economic burden to the healthcare system. By identifying the root causes of the variations in LT-4 dosage, a more comprehensive comprehension of hypothyroidism and its management can be attained in Sri Lanka. Furthermore, upon identification of a positive association/correlation between genetic polymorphisms and the LT-4 dose, SNP profiles can be used as a possible genetic marker for dose adjustment determination in future patients.