Inferences in Log-Rate Models

Log-Rate models are used in analyzing rates of individuals who are exposed to a risk of having a certain characteristic. The explanatory variables could be categorical or in a continuous scale. In finding a Log-Rate Model, parameters are estimated and goodness-of-fit are studied to carefully extract the best model to fit our data. Here we revisit three aspects of Log-Rate Models using the data set give at the end of the paper. The three aspects are parameter estimation, goodness-of-fit of the model, and marginal effect of the factors

Comparative Effectiveness and Safety of Anti–Tumor Necrosis Factor Agents in Biologic-Naive Patients With Crohn’s Disease

Inhibitors of tumor necrosis factor (anti-TNF agents) are the most effective therapy for Crohn’s disease (CD). We evaluated the real-world comparative effectiveness and safety of different anti-TNF agents (infliximab, adalimumab, and certolizumab pegol) in biologic-naïve patients with CD in a retrospective, propensity-matched cohort study using a national administrative claims database (Optum Labs Data Warehouse)

Risk of Malignancy with Vedolizumab Versus Tumor Necrosis Factor-α Antagonists in Patients with Inflammatory Bowel Diseases

Background and aimsWe conducted a retrospective cohort study comparing the risk of malignancy between patients treated with vedolizumab vs. tumor necrosis factor-α (TNFα) antagonists in patients with inflammatory bowel diseases (IBD).MethodsUsing an administrative claims database, we identified patients with IBD without prior malignancy who were new users of either vedolizumab or TNFα antagonists between 2014-2018, with no prior exposure to either biologic or in preceding 1 y and had insurance coverage for at least 1 y after treatment initiation. We estimated incidence rate of malignancy (solid organ, hematological or skin cancers) in patients treated with vedolizumab and TNFα antagonists, and compared risk using Cox proportional hazard analysis.ResultsWe included 4807 patients treated with TNFα antagonists (age, 41 ± 15 y, 60% with Crohn's disease [CD]) of whom 65 developed malignancy over 7214 person-year [PY] follow-up (incidence rate [IR], 9.0 per 1000-PY), and 759 patients treated with vedolizumab (age, 46 ± 16y, 42% CD) of whom 11 developed malignancy over 950-PY follow-up (IR, 11.6). No difference was observed in the incidence of malignancy between vedolizumab versus TNFα antagonists (incidence rate ratio, 1.28; 95% CI, 0.61-2.45). After adjusting for age, sex, race, comorbidity burden, disease phenotype and concomitant use of immunomodulators, no difference was observed in time to incident malignancy between vedolizumab versus TNFα antagonists (HR, 1.15; 95% CI, 0.61-2.19). Similar results were observed on stratified analysis by age and concomitant immunomodulators, and after excluding non-melanoma skin cancers.ConclusionsIn an observational study of patients with IBD, no differences were observed in the risk of incident malignancy in patients treated with vedolizumab versus TNFα antagonists

Frailty and Risk of Serious Infections in Biologic-treated Patients With Inflammatory Bowel Diseases

BackgroundIdentifying biologic-treated patients with inflammatory bowel diseases (IBDs) at higher risk of serious infections is a priority. We conducted a retrospective cohort study evaluating frailty and risk of serious infections in biologic-treated patients with IBD.MethodsUsing an administrative claims database, we identified biologic-treated patients with IBD between 2014 and 2018 with follow-up 1 year before and after treatment initiation. Using a validated claims-based hospital frailty risk scoring system, patients were classified as frail and nonfrail. We compared the risk of serious infections (infections requiring hospitalization) between frail and nonfrail patients using Cox proportional hazard analysis adjusting for age, comorbidities, disease characteristics, health care utilization, use of corticosteroids, immunomodulators, and opiates.ResultsWe included 5987 biologic-treated patients with IBD (4881 on TNFα antagonists, 1106 on vedolizumab), of whom 2350 (39.3%) were classified as frail; over 7115 person-years of follow-up was included, and 520 patients developed serious infection. Frailty was not associated with increased risk of serious infection (adjusted hazard ratio [aHR], 1.12; 95% CI, 0.93-1.36), whereas advanced age (older than 60 years), high comorbidity burden, corticosteroid use, opiate use, and prior serious infection were associated with increased risk of serious infection. On stratified analysis, frailty was associated with increased risk of serious infections in vedolizumab-treated patients (aHR, 1.69; 95% CI, 1.03-2.79) but not in TNFα antagonist-treated patients (aHR, 1.03; 95% CI, 0.83-1.27).ConclusionsIn biologic-treated patients with IBD, frailty assessed using a claims-based frailty index was not independently associated with increased risk of serious infections. Future studies evaluating objective and biological measures of frailty are warranted to risk-stratify older patients with IBD

Comparative Risk of Serious Infections With Tumor Necrosis Factor α Antagonists vs Vedolizumab in Patients With Inflammatory Bowel Diseases

Background and aimsWe conducted a retrospective cohort study comparing the risk of serious infections between patients treated with tumor necrosis factor-a (TNFa) antagonists vs. vedolizumab in patients with inflammatory bowel diseases (IBD).MethodsUsing an administrative claims database, we identified patients with IBD who were new-users of either TNFa antagonists or vedolizumab between 2014-2018 and had insurance coverage for at least 1y before and after treatment initiation. We compared the risk of serious infections (infections requiring hospitalization) between patients treated with vedolizumab or TNFa antagonists using marginal structural Cox proportional hazard models adjusted for baseline disease characteristics, healthcare utilization, comorbidities, and time-varying use of corticosteroids, immunomodulators and opiates.ResultsWe included 4881 patients treated with TNFa antagonists (age, 41 ± 15y, 60% with Crohn's disease [CD]) of whom 434 developed serious infections over 5786 person-year [PY] follow-up, and 1106 patients treated with vedolizumab (age, 44 ± 16y, 39% with CD) of whom 86 developed serious infections over 1040-PY follow-up. Vedolizumab was associated with 46% lower risk of serious infections as compared with TNFa antagonists in patients with ulcerative colitis (HR,0.54 [95% CI,0.35-0.83), but no significant differences were observed in patients with CD (HR,1.30 [0.80-2.11]). Vedolizumab was associated with lower risk of extra-intestinal serious infections in patients with UC, but higher risk of gastrointestinal serious infections in patients with CD.ConclusionsIn an observational study of patients with IBD, vedolizumab was associated with lower risk of serious infections as compared with TNFa antagonists, in patients with UC, but not in patients with CD

Glucagon Prescribing and Costs Among U.S. Adults With Diabetes, 2011-2021

OBJECTIVE: To characterize contemporary trends in glucagon fill rates and expenditures in a nationwide cohort of adults with diabetes overall and by key demographic and clinical characteristics. RESEARCH DESIGN AND METHODS: In this retrospective cohort study, we examined 1) glucagon fill rates per 1,000 person-years and 2) patient out-of-pocket and health plan costs per filled glucagon dose among adults with diabetes included in OptumLabs Data Warehouse between 1 January 2011 and 31 March 2021. RESULTS: The study population comprised 2,814,464 adults with diabetes with a mean age of 62.8 (SD 13.2) years. The overall glucagon fill rate decreased from 2.91 to 2.28 per 1,000 person-years (-22%) over the study period. In groups at high risk for severe hypoglycemia, glucagon fill rates increased from 22.46 to 36.76 per 1,000 person-years (64%) among patients with type 1 diabetes, 11.64 to 16.63 per 1,000 person-years (43%) among those treated with short-acting insulin, and 16.08 to 20.12 per 1,000 person-years (25%) among those with a history of severe hypoglycemia. White patients, women, individuals with high income, and commercially insured patients had higher glucagon fill rates compared with minority patients, males, individuals with low income, and Medicare Advantage patients, respectively. Total cost per dosing unit increased from $157.97 to$275.32 (74%) among commercial insurance beneficiaries and from $150.37 to$293.57 (95%) among Medicare Advantage beneficiaries. CONCLUSIONS: Glucagon fill rates are concerningly low and declined between 2011 and 2021 but increased in appropriate subgroups with type 1 diabetes, using short-acting insulin, or with a history of severe hypoglycemia. Fill rates were disproportionately low among minority patients and individuals with low income

Increased Computed Tomography Utilization in the Emergency Department and Its Association with Hospital Admission

Introduction: Our goal was to investigate trends in computed tomography (CT) utilization in emergency departments (EDs) and its association with hospitalization. Methods: We conducted an analysis of an administrative claims database of U.S. privately insured and Medicare Advantage enrollees. We identified ED visits from 2005 through 2013 and assessed for CT use, associated factors, and hospitalization after CT, along with patient demographics. We used both descriptive methods and regression models adjusted for year, age, sex, race, geographic region, and Hwang comorbidity score to explore associations among CT use, year, demographic characteristics, and hospitalization. Results: We identified 33,144,233 ED visits; 5,901,603 (17.8%) involved CT. Over time, CT use during ED visits increased 59.9%. CT use increased in all age groups but decreased in children since 2010. In propensity-matching analysis, odds of hospitalization increased with age, comorbidities, male sex, and CT use (odds ratio, 2.38). Odds of hospitalization over time decreased more quickly for patients with CT. Conclusion: CT utilization in the ED has increased significantly from 2005 through 2013. For children, CT use after 2010 decreased, indicating caution about CT use. Male sex, older age, and higher number of comorbidities were predictors of CT in the ED. Over time, odds of hospitalization decreased more quickly for patients with CT

Increased Computed Tomography Utilization in the Emergency Department and Its Association with Hospital Admission

Introduction: Our goal was to investigate trends in computed tomography (CT) utilization in emergency departments (EDs) and its association with hospitalization. Methods: We conducted an analysis of an administrative claims database of U.S. privately insured and Medicare Advantage enrollees. We identified ED visits from 2005 through 2013 and assessed for CT use, associated factors, and hospitalization after CT, along with patient demographics. We used both descriptive methods and regression models adjusted for year, age, sex, race, geographic region, and Hwang comorbidity score to explore associations among CT use, year, demographic characteristics, and hospitalization. Results: We identified 33,144,233 ED visits; 5,901,603 (17.8%) involved CT. Over time, CT use during ED visits increased 59.9%. CT use increased in all age groups but decreased in children since 2010. In propensity-matching analysis, odds of hospitalization increased with age, comorbidities, male sex, and CT use (odds ratio, 2.38). Odds of hospitalization over time decreased more quickly for patients with CT. Conclusion: CT utilization in the ED has increased significantly from 2005 through 2013. For children, CT use after 2010 decreased, indicating caution about CT use. Male sex, older age, and higher number of comorbidities were predictors of CT in the ED. Over time, odds of hospitalization decreased more quickly for patients with CT

Comparative Effectiveness and Safety of Anti–Tumor Necrosis Factor Agents in Biologic-Naive Patients With Crohn’s Disease

Inhibitors of tumor necrosis factor (anti-TNF agents) are the most effective therapy for Crohn’s disease (CD). We evaluated the real-world comparative effectiveness and safety of different anti-TNF agents (infliximab, adalimumab, and certolizumab pegol) in biologic-naïve patients with CD in a retrospective, propensity-matched cohort study using a national administrative claims database (Optum Labs Data Warehouse)