Development and Validation of ICD-10-CM-based Algorithms for Date of Last Menstrual Period, Pregnancy Outcomes, and Infant Outcomes.

INTRODUCTION AND OBJECTIVE: Validation studies of algorithms for pregnancy outcomes based on International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes are important for conducting drug safety research using administrative claims databases. To facilitate the conduct of pregnancy safety studies, this exploratory study aimed to develop and validate ICD-10-CM-based claims algorithms for date of last menstrual period (LMP) and pregnancy outcomes using medical records. METHODS: Using a mother-infant-linked claims database, the study included women with a pregnancy between 2016-2017 and their infants. Claims-based algorithms for LMP date utilized codes for gestational age (Z3A codes). The primary outcomes were major congenital malformations (MCMs) and spontaneous abortion; additional secondary outcomes were also evaluated. Each pregnancy outcome was identified using a claims-based simple algorithm, defined as presence of ≥ 1 claim for the outcome. Positive predictive values (PPV) and 95% confidence intervals (CI) were calculated. RESULTS: Overall, 586 medical records were sought and 365 (62.3%) were adjudicated, including 125 records each for MCMs and spontaneous abortion. Last menstrual period date was validated among maternal charts procured for pregnancy outcomes and fewer charts were adjudicated for the secondary outcomes. The median difference in days between LMP date based on Z3A codes and adjudicated LMP date was 4.0 (interquartile range: 2.0-10.0). The PPV of the simple algorithm for spontaneous abortion was 84.7% (95% CI 78.3, 91.2). The PPV for the MCM algorithm was < 70%. The algorithms for the secondary outcomes pre-eclampsia, premature delivery, and low birthweight performed well, with PPVs > 70%. CONCLUSIONS: The ICD-10-CM claims-based algorithm for spontaneous abortion performed well and may be used in pregnancy studies. Further algorithm refinement for MCMs is needed. The algorithms for LMP date and the secondary outcomes would benefit from additional validation in a larger sample.

Predictors of critical care, mechanical ventilation, and mortality among hospitalized patients with COVID-19 in an electronic health record database.

BACKGROUND: There are limited data on risk factors for serious outcomes and death from COVID-19 among patients representative of the U.S. POPULATION: The objective of this study was to determine risk factors for critical care, ventilation, and death among hospitalized patients with COVID-19. METHODS: This was a cohort study using data from Optum's longitudinal COVID-19 electronic health record database derived from a network of healthcare provider organizations across the US. The study included patients with confirmed COVID-19 (presence of ICD-10-CM code U07.1 and/or positive SARS-CoV-2 test) between January 2020 and November 2020. Patient characteristics and clinical variables at start of hospitalization were evaluated for their association with subsequent serious outcomes (critical care, mechanical ventilation, and death) using odds ratios (OR) and 95% confidence intervals (CI) from logistic regression, adjusted for demographic variables. RESULTS: Among 56,996 hospitalized COVID-19 patients (49.5% male and 72.4% ≥ 50 years), 11,967 received critical care, 9136 received mechanical ventilation, and 8526 died. The median duration of hospitalization was 6 days (IQR: 4, 11), and this was longer among patients that experienced an outcome: 11 days (IQR: 6, 19) for critical care, 15 days (IQR: 8, 24) for mechanical ventilation, and 10 days (IQR: 5, 17) for death. Dyspnea and hypoxemia were the most prevalent symptoms and both were associated with serious outcomes in adjusted models. Additionally, temperature, C-reactive protein, ferritin, lactate dehydrogenase, D-dimer, and oxygen saturation measured during hospitalization were predictors of serious outcomes as were several in-hospital diagnoses. The strongest associations were observed for acute respiratory failure (critical care: OR, 6.30; 95% CI, 5.99-6.63; ventilation: OR, 8.55; 95% CI, 8.02-9.11; death: OR, 3.36; 95% CI, 3.17-3.55) and sepsis (critical care: OR, 4.59; 95% CI, 4.39-4.81; ventilation: OR, 5.26; 95% CI, 5.00-5.53; death: OR, 4.14; 95% CI, 3.92-4.38). Treatment with angiotensin-converting enzyme inhibitors/angiotensin receptor blockers during hospitalization were inversely associated with death (OR, 0.57; 95% CI, 0.54-0.61). CONCLUSIONS: We identified several clinical characteristics associated with receipt of critical care, mechanical ventilation, and death among COVID-19 patients. Future studies into the mechanisms that lead to severe COVID-19 disease are warranted.

Safety study of live, oral human rotavirus vaccine: A cohort study in United States health insurance plans.

As part of a regulatory commitment for post-licensure safety monitoring of live, oral human rotavirus vaccine (RV1), this study compared the incidence rates (IR) of intussusception, acute lower respiratory tract infection (LRTI) hospitalization, Kawasaki disease, convulsion, and mortality in RV1 recipients versus inactivated poliovirus vaccine (IPV) recipients in concurrent (cIPV) and recent historical (hIPV) comparison cohorts. Vaccine recipients were identified in 2 claims databases from August 2008 - June 2013 (RV1 and cIPV) and January 2004 - July 2008 (hIPV). Outcomes were identified in the 0-59 days following the first 2 vaccine doses. Intussusception, Kawasaki disease, and convulsion were confirmed via medical record review. Outcome IRs were estimated. Incidence rate ratios (IRRs) were obtained from Poisson regression models. A post-hoc self-controlled case series (SCCS) analysis compared convulsion IRs in a 0-7 day post-vaccination period to a 15-30 day post-vaccination period. We identified 57,931 RV1, 173,384 cIPV, and 159,344 hIPV recipients. No increased risks for intussusception, LRTI, Kawasaki disease, or mortality were observed. The convulsion IRRs were elevated following RV1 Dose 1 (cIPV: 2.07, 95% confidence interval [CI]: 1.27 - 3.38; hIPV: 2.05, 95% CI: 1.24 - 3.38), a finding which is inconclusive as it was observed in only one of the claims databases. The IRR following RV1 Dose 1 in the SCCS analysis lacked precision (2.40, 95% CI: 0.73 - 7.86). No increased convulsion risk was observed following RV1 Dose 2. Overall, this study supports the favorable safety profile of RV1. Continued monitoring for safety signals through routine surveillance is needed to ensure vaccine safety.

Hypoglycaemia seriousness and weight gain as determinants of cardiovascular disease outcomes among sulfonylurea users.

AIMS: Certain treatments for type 2 diabetes mellitus cause hypoglycaemia and weight gain, and thus might counteract the benefits of intensive glucose control. We quantify the association of cardiovascular disease (CVD) outcomes with hypoglycaemia and weight gain among patients with type 2 diabetes treated with sulfonylureas. MATERIALS AND METHODS: This cohort study included patients from January 2009 through December 2014 who were selected from within a deidentified nationwide electronic health records repository, including multiple provider networks and electronic medical records systems. Hypoglycaemia measures from structured data fields and free text clinical notes were categorized as serious or non-serious. Covariate adjusted Poisson regression analysis was used to assess the association between frequency of hypoglycaemia (by severity), or magnitude of weight change, and incidence of acute myocardial infarction (AMI), congestive heart failure (CHF) and stroke. RESULTS: Among 143 635 eligible patients, we observed 5669 cases of AMI, 14 109 incident cases of CHF and 7017 cases of stroke. Overall incidence rates were 1.53, 4.26 and 1.92 per 100 person-years for AMI, CHF and stroke, respectively. The associations between overall hypoglycaemia and each of the CVD outcomes were positive, with stronger associations observed for serious hypoglycaemia and attenuated or null associations observed for non-serious hypoglycaemia. Weight change exhibited a U-shaped association with increased risks associated with both weight loss and weight gain relative to stable weight. CONCLUSIONS: This study provides evidence of increased CVD risk associated with hypoglycaemia, especially with serious hypoglycaemia events. While associations were attenuated with non-serious hypoglycaemia, the results were suggestive of a potential increased risk.

Assessing occurrence of hypoglycemia and its severity from electronic health records of patients with type 2 diabetes mellitus.

AIMS: Accurate measures of hypoglycemia within electronic health records (EHR) can facilitate clinical population management and research. We quantify the occurrence of serious and mild-to-moderate hypoglycemia in a large EHR database in the US, comparing estimates based only on structured data to those from structured data and natural language processing (NLP) of clinical notes. METHODS: This cohort study included patients with type 2 diabetes identified from January 2009 through March 2014. We compared estimates of occurrence of hypoglycemia derived from diagnostic codes to those recorded within clinical notes and classified via NLP. Measures of hypoglycemia from only structured data (ICD-9 Algorithm), only note mentions (NLP Algorithm), and either structured data or notes (Combined Algorithm) were compared with estimates of the period prevalence, incidence rate, and event rate of hypoglycemia, overall and by seriousness. RESULTS: Of the 844,683 eligible patients, 119,695 had at least one recorded hypoglycemic event identified with ICD-9 or NLP. The period prevalence of hypoglycemia was 12.4%, 25.1%, and 32.2% for the ICD-9 Algorithm, NLP Algorithm, and Combined Algorithm, respectively. There were 6128 apparent non-serious events utilizing the ICD-9 Algorithm, which increased to 152,987 non-serious events within the Combined Algorithm. CONCLUSIONS: Ascertainment of events from clinical notes more than doubled the completeness of hypoglycemia capture overall relative to measures from structured data, and increased capture of non-serious events more than 20-fold. The structured data and clinical notes are complementary within the EHR, and both need to be considered in order to fully assess the occurrence of hypoglycemia.

Postmarketing evaluation of the short-term safety of the pentavalent rotavirus vaccine.

BACKGROUND: A pentavalent rotavirus vaccine (RV5) demonstrated efficacy and safety in a large clinical trial before US licensure in 2006. The primary objective of this observational study was to assess the occurrence of intussusception (IS) among infants who received RV5 in routine use. Secondary objectives assessed the occurrence of Kawasaki disease (KD) and general safety. METHODS: We identified and followed infants with a health insurance claim for RV5 during the first 2 years of RV5 availability. Concurrent and historical cohorts receiving diphtheria-tetanus-acellular pertussis (DTaP) vaccine were used as comparators; the historical DTaP cohort informed sequential monitoring boundaries for IS and KD. Medical records from potential IS and KD cases were reviewed to confirm outcomes. General safety was evaluated across a wide range of outcomes using prespecified criteria. Incidence rates for outcomes along with relative risks and 95% confidence intervals (CIs) were estimated. RESULTS: The 85,397 RV5 and 62,820 DTaP recipients contributed 17,433 and 12,339 person-years, resulting in 6 and 5 confirmed cases of IS, respectively, within 30 days following any dose. The relative risk of IS was 0.8 (95% confidence interval: 0.22-3.52). The number of IS or KD cases did not cross the monitoring boundaries. The general safety evaluation did not identify any specific diagnoses or patterns of diagnoses that might suggest other safety concerns. CONCLUSION: RV5 was not associated with an increased risk of IS, KD, or any other recognized health outcome.

The prevalence and risk factors associated with esophageal varices in subjects with hepatitis C and advanced fibrosis.

BACKGROUND: The factors predictive of the presence or the absence of esophageal varices in hepatitis C virus (HCV) and advanced fibrosis have not been defined. OBJECTIVES: To define the prevalence of esophageal varices and the factors that are positively and negatively with such varices in hepatitis C and advanced fibrosis. DESIGN: A prospective study of esophageal varices and associated risk factors in subjects with hepatitis C and advanced fibrosis. SETTING: Prerandomization data from the HALT-C (hepatitis C long-term antiviral treatment against cirrhosis) clinical trial. PATIENTS AND INTERVENTION: Subjects with bridging fibrosis or cirrhosis, who were virologic nonresponders to treatment with pegylated interferon alpha 2a and ribavirin, underwent endoscopy. RESULTS: Sixteen percent of subjects with bridging fibrosis (95/598) and 39% of subjects with cirrhosis (164/418) had varices (P < .0001); 2% of subjects with bridging fibrosis (13/598) and 11% of those with cirrhosis (48/418) had medium or large varices. Subjects with bridging fibrosis and varices had a significantly lower platelet count and higher bilirubin and international normalized ratio (INR) compared with those without varices, suggesting that the biopsy may have underestimated the severity of fibrosis. A platelet count >150,000/mm(3) was associated with a negative predictive value of 99% for esophageal varices. By logistic regression modeling, African American race and female sex were protective, whereas a lower platelet count and higher bilirubin and INR predicted varices (c statistic, 0.758). CONCLUSIONS: The risk of having varices increases with decreasing platelet counts, increasing bilirubin, and INR. The probability of having medium or large varices at platelet counts >150,000/mm(3) is negligible in this population.

Portal hypertensive gastropathy in chronic hepatitis C patients with bridging fibrosis and compensated cirrhosis: results from the HALT-C trial.

OBJECTIVES: The clinical significance of portal hypertensive gastropathy (PHG) in patients with compensated liver disease is not well established. The aim of this study was to determine the prevalence and correlates of PHG in a large cohort of patients with chronic hepatitis C virus (HCV) infection and bridging fibrosis/compensated cirrhosis entering the randomized phase of the Hepatitis C Antiviral Long-term Treatment against Cirrhosis trial (HALT-C). METHODS: The presence and severity of PHG in 1,016 HCV patients with no prior history of gastrointestinal bleeding was determined at surveillance endoscopy using the New Italian Endoscopy Club criteria. RESULTS: Overall, 37% of HALT-C patients had PHG with 34% having mild and 3% with severe changes. The mucosal mosaic pattern was identified in 33%, red marks in 15%, and gastric antral vascular ectasia (GAVE) features in only 3%. Independent correlates of PHG included biochemical markers of liver disease severity (lower serum albumin, higher bilirubin), portal hypertension (lower platelet count), insulin resistance (higher glucose), and non-African American race. Independent correlates of GAVE included a history of smoking, nonsteroidal anti-inflammatory drugs (NSAIDs) use within the past year, and higher serum bilirubin and glucose levels. There was a strong positive association between the presence of PHG and esophageal varices (p < 0.0001). CONCLUSIONS: PHG is associated with the histological and biochemical severity of liver disease in patients with HCV and advanced fibrosis but is mild in most patients. The clinical relevance of these findings will be further explored during the randomized phase of the HALT-C study.

Hepatitis C virus-specific immune responses and quasi-species variability at baseline are associated with nonresponse to antiviral therapy during advanced hepatitis C.

Pretreatment hepatitis C virus (HCV)-specific lymphoproliferative (LP) responses, neutralizing antibody (NA) responses, intrahepatic cytotoxic T lymphocyte (CTL) responses, and HCV quasi-species (QS) diversity and complexity were examined in patients with advanced hepatic fibrosis (Ishak fibrosis score of > or = 3) and prior nonresponse to interferon (IFN)- alpha therapy who were enrolled in the initial phase of the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis Trial. Positive baseline HCV E1- and/or E2-specific NA responses (P = .01) and higher baseline HCV QS diversity (P = .01) were more commonly found in patients who did not become sustained virologic responders (SVRs) at week 72 (W72) than they were in those who did. No patients with positive results for both the LP and NA assays achieved a sustained virologic response. Multiple logistic regression analysis revealed that, when the presence of cirrhosis, prior ribavirin therapy, genotype 1 infection, log serum HCV RNA level, and receipt of >80% of the prescribed medication were controlled for, a sustained virologic response (W72) was negatively correlated with positive baseline LP assay results (P = .02) and with 1 or more positive assays (LP, NA, or CTL) (P = .02). No differences were noted in baseline intrahepatic CTL activity between SVRs and non-SVRs. Thus, in patients with advanced hepatic fibrosis due to HCV infection, pretreatment HCV-specific immune responses and increased QS variability appear to hinder viral clearance by pegylated IFN- alpha 2a and ribavirin combination therapy.