Neurogenic heterotopic ossification of the hip: Magnetic resonance imaging versus computed tomography for pre-surgical assessment.

PURPOSE: Neurogenic heterotopic ossification (NHO) of the hip is a frequent complication of spinal cord injuries, often requiring surgical management. Pre-surgical imaging assessment is essential, usually with computed tomography (CT)-scan. We aimed to compare magnetic resonance imaging (MRI) and CT for pre-surgical imaging assessment of the NHO, particularly for their relationships with vessels and nerves. METHOD: This prospective study included consecutive patients who underwent surgery for NHO from July 2019 to April 2022. All patients had CT angiography and MRI including Zero Echo Time and TRICKS sequences. Radiologists used standardized reports for CT and MRI to evaluate NHO and their features, bone mineralization, and relation to the arteries, veins and nerves. Agreement between pre-surgical CT and MRI was evaluated. RESULTS: Twenty-four patients (mean age: 53.5 ± 12.2 years) were included, among which 7 had bilateral NHO (31 hips). NHO were anterior in 15/31 hips (48 %), multifragmented in 25/31 hips (81 %). Mild and significant demineralization was most frequent. Gutter and tunnel were reported in 11.1 % of the arteries. Nerves were more often identified in MRI than in CT-scan. Agreement coefficients between CT and MRI were excellent for NHO location (0.95) and implantation (0.92), good for fragmentation (0.70), contact with joint capsule (0.66), bone mineralization (0.74), and relation to arteries (0.85), veins (0.76), sciatic nerve (0.7) and moderate for femoral nerve (0.47). CONCLUSION: MRI exhibited a good agreement with CT for pre-surgical assessment of NHO of the hip, especially to evaluate their relationships with the arteries, veins and sciatic nerve. Femoral nerves were more often identified in MRI than in CT-scan.

Association between vaccination and the risk of central demyelination: results from a case-referent study.

BACKGROUND: Few studies documented the potential association between vaccination and the risk of central demyelination (CD). Specifically, anti-hepatitis B and anti-human papillomavirus (HPV) vaccines have been the subject of distrust with regard to their implication to trigger CD. METHODS: From a systematic national registry, patients with first signs of CD (cases) were identified and documented for their exposure to vaccination up to 24 months before the first signs occurred. This exposure was compared to that of a representative sample of general practice patients without a history of CD, randomly selected from a national registry (referents). CD cases were 2:1 matched on age, sex, index date (ID), and region of residence. Vaccines against influenza, HPV, hepatitis B and diphtheria-tetanus-pertussis-poliomyelitis-haemophilus (DTPPHae) were considered. Associations between vaccination and CD were assessed using multivariate conditional logistic regressions, controlled for confounding factors. FINDINGS: 564 CD cases were matched to 1,128 randomly selected referents (age range: 2-79 years old). Overall, 123 (22%) CD cases and 320 (28%) referents had received at least one vaccine within 24 months before ID. Adjusted odds ratios (ORs) for any vaccination were 0.69, 95% confidence interval (CI) [0.54-0.88] with respect to any CD first signs, 0.68 [0.51-0.90] for myelitis and 0.70 [0.42-1.17] for optic neuritis. Adjusted ORs for any CD first signs were 1.02 [0.71-1.47] for influenza vaccine (administered in 9.6% of cases and 10.4% of referents) and 0.72 [0.53-0.99] for DTPPHae vaccine (administered in 10.8% of cases and 14.5% of referents). Vaccines against hepatitis B and HPV were only administered in 1.1% and 1.2% of cases and in 2.9% and 3.2% of referents respectively, which statistically explained the point estimates < 1 (ORs of 0.39 [0.16-0.94] and of 0.32 [0.13-0.80]). INTERPRETATION: No increased risk of CD incidence was observed amongst vaccinated patients. Lower rates of vaccination against hepatitis B and HPV observed in patients with CD compared to referents may be due to the reluctance of physicians to vaccinate patients considered at risk of CD.

The systematic case-referent method.

The systematic case-referent method is a special case-referent design originally developed for pharmacoepidemiologic research purposes. It consists in the systematic collection of series of incident cases of various disorders and the assembling of a general reference pool, from which "controls" are secondarily selected to be matched to specific cases. Both series are collected independently from each other and with no a priori hypothesis to be investigated. The reference pool can be either general or limited to a subpopulation, representative of the source population of the cases. Based on clinical recruitment of cases and referents, the design allows a very high specificity of diagnosis and documentation of clinical variables. All cases and referents are systematically documented on all treatments received before the incidence of the cases or before identification of referents. This documentation is done preferentially using objective sources assembled independently (linkage to claims data, medical records, pharmacy records, prescription records, hospital discharge letters). It can be completed with patients' interviews using standardised research tools, in particular for over-the-counter drug use and self-medication, and for the documentation of adherence to treatment and specific time-windows of exposure. Likewise, all cases and all referents are systematically documented on a series of risk factors, which are common to most epidemiological studies and are not hypothesis-dependent. Whenever the documentation of a confounding factor specific to the disease at hand is necessary, additional questionnaires can be applied to all or a sample of patients. The method has been successfully implemented for the pharmacoepidemiologic study of myocardial infarction, stroke, lupus, multiple sclerosis, rheumatoid arthritis, Guillain Barré syndrome, idiopathic thrombocytopenic purpura, type 1 diabetes mellitus, suicide attempts, breast cancer, and other disorders, for the analysis of the risk or preventing action of NSAIDs, statins, antiplatelet agents, anticoagulants, insulins, vaccines and other drugs.

Correlates and predictors of antipsychotic drug polypharmacy in real-life settings: Results from a nationwide cohort study.

Reasons for using antipsychotic polypharmacy (APP) in routine clinical practice, despite a potentially unfavorable risk-benefit ratio, are poorly understood. This research aimed to determine (1) if severe courses of schizophrenia were associated with APP and (2) if a schizophrenia-related acute event would predict a switch to APP in the short term. Observational prospective data (at baseline and 6months) were drawn from a French nationwide cohort ("Cohorte Générale Schizophrénie"), which included 1859 inpatients and outpatients with schizophrenia. APP was defined as the prescription of ≥2 antipsychotic drugs (there being different active substances). Early-onset schizophrenia, legal guardianship, higher lifetime maximal severity of illness and comorbid antisocial personality were used as proxies for severe courses of schizophrenia. Schizophrenia-related acute events included hospitalization and recent suicide attempts. Logistic regression models were used to determine (1) whether the use of APP at baseline (vs. monotherapy) was associated with a severe course of schizophrenia or not, independent of acute events, and (2) if a switch to APP at 6months (vs. remaining on monotherapy) was associated with acute events, independent of severe courses of schizophrenia. Increased odds of APP use at baseline were independently associated with legal guardianship (OR=1.6; 95%CI=1.3, 2.0) and higher lifetime maximum severity of illness (OR=1.3; 95%CI=1.2, 1.5). A switch to APP at 6months was predicted by a hospitalization occurring since baseline (OR=6.1; 95%CI=3.9, 9.4). In routine clinical practice, APP is more likely prescribed to patients with severe courses of illness, possibly indicating the difficulty to manage these patients.

Risk of autoimmune diseases and human papilloma virus (HPV) vaccines: Six years of case-referent surveillance.

BACKGROUND: Safety of HPV vaccines is still in question due to reports of autoimmune diseases (ADs) following HPV immunization. OBJECTIVES: To assess the risk of ADs associated with HPV vaccination of female adolescents/young adults in France. METHODS: Systematic prospective case-referent study conducted to assess the risks associated with real-life use of HPV vaccines. Cases were female 11-25 years old with incident ADs [central demyelination/multiple sclerosis (CD/MS), connective tissue disease (CTD), Guillain-Barré syndrome (GBS), type-1 diabetes (T1D), autoimmune thyroiditis (AT), and idiopathic thrombocytopenic purpura (ITP)]. Cases were consecutively and prospectively identified at specialized centers across France (2008-2014) and individually matched by age and place of residence to referents recruited in general practice. Risk was computed using multivariate conditional logistic regression models adjusted for family history of ADs, living in France (north/south), co-medications and co-vaccinations. RESULTS: With a total of 478 definite cases matched to 1869 referents, all ADs combined were negatively associated to HPV vaccination with an adjusted odds ratio of 0.58 (95% confidence interval: 0.41-0.83). Similar results were obtained for CD/MS, AT, CT, and T1D, the last two not reaching statistical significance. No association was found for ITP and GBS. Sensitivity analyses combining definite and possible cases with secondary time window showed similar results. CONCLUSION: Exposure to HPV vaccines was not associated with an increased risk of ADs within the time period studied. Results were robust to case definitions and time windows of exposure. Continued active surveillance is needed to confirm this finding for individual ADs.

Childhood immune thrombocytopenia: A nationwide cohort study on condition management and outcomes.

OBJECTIVES: Nationwide prospective cohort study exploring (i) the factors associated with treatment initiation (vs. watchful waiting) in children with primary immune thrombocytopenia (ITP) followed in routine clinical practice and (ii) the predictors of chronicity at 12 months. PROCEDURE: Between 2008 and 2013, 23 centers throughout France consecutively included 257 children aged 6 months-18 years and diagnosed with primary ITP over a 5-year period. Data on ITP clinical features along with medical management were collected at baseline and 12 months. Multivariate logistic regressions were used to determine (i) and (ii) as defined above, providing odds ratio (OR) with 95% confidence interval (95% CI). RESULTS: One hundred thirty-seven (53%) children were males, median age was 4.6 years, median platelet count was 7 × 109/l, and 214 (81%) patients initiated medication. Factors independently associated with treatment initiation included platelet counts <10 × 109/l (P < 0.0001) and mucocutaneous bleeding symptoms at baseline (P < 0.001). At 12 months, data were available for 211 (82%) children, of whom 160 (74%) had recovered. Predictors of chronicity included female gender (OR = 2.2; 95% CI = 1.0-4.8), age ≥10 years (OR = 2.6; 95% CI = 1.1-6.0), and platelet counts ≥10 × 109 /l (OR = 3.2; 95% CI = 1.5-6.9). CONCLUSIONS: In routine clinical practice, the decision to apply a watchful waiting strategy seems to be driven by platelet counts even in the absence of bleeding symptoms, resulting in treatment being initiated in more than 80% of the children surveyed. Overall, younger children with ITP showed good prognosis, with lower platelet counts and, to a lesser extent, male gender predicting more favorable outcomes.

Calcium channel blockers and cancer: a risk analysis using the UK Clinical Practice Research Datalink (CPRD).

OBJECTIVE: The evidence of an association between calcium channel blockers (CCBs) and cancer is conflicting. The objective of the present study was to evaluate the risk of cancer (all, breast, prostate and colon cancers) in association with exposure to CCB. METHODS: This is a population-based cohort study in patients exposed to CCBs from across the UK, using two comparison cohorts: (1) patients with no exposure to CCB (non-CCB) matched on age and gender and (2) unmatched patients unexposed to CCB and at least one other antihypertensive (AHT) prescription. Cancer incidence rates computed in the exposed and the two unexposed groups were compared using HRs and 95% CIs obtained from multivariate Cox regression analyses. RESULTS: Overall, 150,750, 557,931 and 156,966 patients were included, respectively, in the CCB, non-CCB and AHT cohorts. Crude cancer incidence rates per 1000 person-years were 16.51, 15.75 and 10.62 for the three cohorts, respectively. Adjusted HRs (CI) for all cancers comparing CCB, non-CCB and AHT cohorts were 0.88 (0.86 to 0.89) and 1.01 (0.98 to 1.04), respectively. Compared to the AHT cohort, adjusted HRs (CI) for breast, prostate and colon cancer for the CCB cohort were 0.95 (0.87 to 1.04), 1.07 (0.98 to 1.16) and 0.89 (0.81 to 0.98), respectively. Analyses by duration of exposure to CCB did not show excess risk. CONCLUSIONS: This large population-based study provides strong evidence that CCB use is not associated with an increased risk of cancer. The analyses yielded robust results across all types of cancer and different durations of exposure to CCBs.

Risk of breast cancer by individual insulin use: an international multicenter study.

OBJECTIVE Several studies have been published in 2009 suggesting a possible association between insulin glargine and increased risk of malignancies, including breast cancer. The objective of this study was to assess the relation between the individual insulins (glargine, aspart, lispro, and human insulin) and development of breast cancer. RESEARCH DESIGN AND METHODS Seven hundred seventy-five incident cases of primary invasive or in situ carcinoma breast cancer occurring in women with diabetes from 92 centers in the U.K., Canada, and France were matched to a mean of 3.9 diabetic community control subjects (n = 3,050; recruited from 580 general practices) by country, age, recruitment date, and diabetes type and management. The main risk model was a multivariate conditional logistic regression model with case/control status as the dependent variable and individual insulin use, 8 years preceding the index date, as the independent variable, controlling for past use of any insulin, oral antidiabetes drugs, reproductive factors, lifestyle, education, hormone replacement therapy and history of contraceptive use, BMI, comorbidities, diabetes duration, and annual number of physician visits. Glargine was also compared with every other insulin by computing all ratios using the variance-covariance matrix of logistic model parameters. RESULTS Adjusted odds ratios of breast cancer for each type of insulin versus no use of that insulin were 1.04 (95% CI 0.76-1.44) for glargine, 1.23 (0.79-1.92) for lispro, 0.95 (0.64-1.40) for aspart, and 0.81 (0.55-1.20) for human insulin. Two-by-two comparisons found no difference between glargine and the different types of insulins. Insulin dosage or duration of use and tumor stage did not change the results. CONCLUSIONS This international study found no difference in the risk of developing breast cancer in patients with diabetes among the different types of insulin with short- to mid-term duration of use. Longer-term studies would be of interest.

Bridging differences in outcomes of pharmacoepidemiological studies: design and first results of the PROTECT project.

BACKGROUND: Observational pharmacoepidemiological (PE) studies on drug safety have produced discrepant results that may be due to differences in design, conduct and analysis. PURPOSE: The pharmacoepidemiology work-package (WP2) of the Pharmacoepidemiological Research on Outcomes of Therapeutics by a European ConsorTium (PROTECT) project aims at developing, testing and disseminating methodological standards for design, conduct and analysis of pharmacoepidemiological studies applicable to different safety issues using different databases across European countries. This article describes the selection of the safety issues and the description of the databases to be systematically studied. METHODS: Based on two consensus meetings and a literature search, we selected five drug-adverse event (AE) pairs to be evaluated in different databases. This selection was done according to pre-defined criteria such as regulatory and public health impact, and the potential to investigate a broad range of methodological issues. RESULTS: The selected drug-AE pairs are: 1) inhaled long-acting beta-2 agonists and acute myocardial infarction; 2) antimicrobials and acute liver injury; 3) antidepressants and/or benzodiazepines and hip fracture; 4) anticonvulsants and suicide/suicide attempts; and 5) calcium channel blockers and malignancies. Six European databases, that will be used to evaluate the drug-AE pairs retrospectively, are also described. CONCLUSION: The selected drug-AE pairs will be evaluated in PE studies using common protocols. Based on consistencies and discrepancies of these studies, a framework for guiding methodological choices will be developed. This will increase the usefulness and reliability of PE studies for benefit-risk assessment and decision-making.

Does omalizumab make a difference to the real-life treatment of asthma exacerbations?: Results from a large cohort of patients with severe uncontrolled asthma.

BACKGROUND: Omalizumab has been shown to decrease the risk of hospitalization or ED visits in patients with uncontrolled severe allergic asthma compared with placebo. This longitudinal study observed the conditions under which omalizumab is prescribed in real-life settings and assessed whether its use as an add-on therapy alongside standard treatments decreases the risk of severe asthmatic exacerbations. METHODS: A cohort of adult patients with uncontrolled severe asthma despite optimal treatment with inhaled and oral corticosteroids and a long-acting b 2 -agonist but no treatment with omalizumab upon entry was assembled. Risk of hospitalization or ED visits for asthma exacerbation was assessed using the Andersen-Gill extension of the Cox model for repeated events, controlling for age, sex, smoking history, BMI, gastroesophageal reflux, allergic status, allergic rhinitis, treatment, and hospitalization or ED visits for asthma in the 2 months prior to omalizumab treatment. RESULTS: Overall, 163 physicians recruited 767 patients, of whom 374 took omalizumab at least once (mean observation period, 20.4 months). Omalizumab use was associated with an adjusted relative risk of 0.57 (95% CI, 0.43-0.78) for hospitalization or ED visits for asthma. In users of omalizumab, the adjusted relative risk of hospitalization or ED visits for asthma during omalizumab treatment vs nontreatment periods was 0.40 (95% CI, 0.28-0.58). CONCLUSIONS: Add-on omalizumab is associated with a significantly decreased risk of hospitalization or ED visits in patients with uncontrolled severe asthma in real-life practice.

Agreement between patients' self-report and medical records for vaccination: the PGRx database.

PURPOSE: Patients' self-reported vaccine exposure (PS) may be subject to memory errors and other biases. Physicians' prescription records and other medical records (MR) do not capture noncompliance with vaccination. This study compared PS with MR for influenza, 23-valent pneumococcal, and human papillomavirus (HPV) vaccines. METHODS: The Pharmacoepidemiologic General Research Extension (PGRx) database uses a network of over 300 general practitioners across France, who systematically recruit an age- and sex-stratified sample of patients (≥ 14 years old), without reference to their diagnoses or prescriptions. Patients received a structured telephone interview, combined with an interview guide listing vaccines commonly given. Patients' self-reported vaccination in the 3 years before their recruitment was compared with medical records kept by the physician or the patient. RESULTS: Concordance between PS and MR was assessed for 7613 patients for whom both sources of information were available. Agreement within 3 years before the recruitment date was substantial for influenza vaccines (prevalence and bias-adjusted kappa [PABAK] = 0.74, sensitivity PS relative to MR 81.5%) and high for 23-valent pneumococcal vaccines (PABAK = 0.98, sensitivity PS 49.6) and HPV vaccines (PABAK = 0.92, sensitivity PS 91.6). In adjusted analyses, agreement varied with sociodemographic and health-related factors, particularly for influenza and 23-valent pneumococcal vaccines. CONCLUSIONS: The PGRx method for drug exposure assessment is a new tool in pharmacoepidemiology that shows substantial to high agreement between PS and MR for exposure to various vaccines. Our finding of high agreement between PS and MR for HPV vaccination status in young women is a significant addition to the literature.

Clinical features and risk factors for upper gastrointestinal bleeding in children: a case-crossover study.

OBJECTIVE: This population-based survey was conducted to provide a formal description of upper gastrointestinal bleeding (UGIB) in children on a nationwide basis and assess the contribution of risk factors, principally nonsteroidal anti-inflammatory drugs (NSAID). METHODS: A case-crossover study of UGIB patients aged between 2 months and 16 years was conducted in France. Medical data were collected by physicians, and personal risk factors and exposure to drugs during the month preceding the onset of the bleeding was ascertained by a standardised telephone interview with parents. The odds ratios for UGIB and NSAID was assessed by comparing exposure during the 7 days preceding the date of hospitalisation and the 21st to the 28th days before that date. RESULTS: A total of 177 children with UGIB were included over 2 years. Eighty-three children had taken at least one NSAID before the index date, among which 58 were ibuprofen, 26 aspirin and nine others. The adjusted odds ratio (OR) of exposure was 8.2 [95% confidence interval (CI) 2.6-26.0] for NSAIDs altogether, and this was 10.0 (95% CI 2.0-51.0) for ibuprofen and 7.3 (95% CI 0.9-59.4) for aspirin. There was no increased risk associated with NSAIDS for oesophageal lesion [OR = 1.0 [(5% CI:0.2-7.2)]. CONCLUSION: The study confirms that UGIB is rare but that some cases may be avoided, as one third of the cases was attributable to exposure to NSAID at doses used for analgesic or antipyretic purposes, which may be attained with alternative therapy. The findings from this study call for more caution in prescribing NSAIDS to children.