Background Incidence Rates Research Articles

Spontaneous reporting of suspected narcolepsy after vaccination against pandemic influenza A (H1N1) in Germany.

We aimed at investigating whether, in Germany, the number of individual case safety reports (ICSR) of confirmed narcolepsy following Pandemrix® vaccination notified to the Paul-Ehrlich-Institut (PEI, German Federal Institute for Vaccines and Biomedicines) was higher than expected when compared with the prepandemic background incidence rates. ICSR of narcolepsy after vaccination with Pandemrix® notified to the PEI until September 2016 were reviewed and validated according to the criteria of narcolepsy defined by the Brighton Collaboration (BC). Cases fulfilling the criteria of BC levels of diagnostic certainty 1 to 4a with symptoms onset after vaccination with Pandemrix® were eligible. Adjustment for underreporting was performed with cases of narcolepsy recruited within the scope of the German Narcolepsy Study using capture-recapture methods. An observed versus expected (OvE) analysis was conducted based on adjusted case numbers using risk windows for symptoms onset within 4 and 6months following vaccination. By the end of September 2016, a total of 85 ICSR of narcolepsy after vaccination with Pandemrix® had been notified to the PEI 52 of which were eligible. The OvE estimates for the 4 and 6months risk windows were 3.8 (95% CI: 2.6-5.4) and 2.8 (95% CI: 2.0-3.9), respectively. The number of excess cases was higher in children and adolescents (15-fold and 11.7-fold increased OvE estimate) than in adults (2.1-fold and 1.5-fold increased estimate). Compared with the prepandemic background incidence rate, the number of incident narcolepsy cases was 3.8-fold and 2.8-fold as high.

Survival of 86,690 patients with thyroid cancer: A population-based study in 29 European countries from EUROCARE-5

BackgroundIncidence rates of thyroid cancer (TC) increased in several countries during the last 30 years, while mortality rates remained unchanged, raising important questions for treatment and follow-up of TC patients. This study updates population-based estimates of relative survival (RS) after TC diagnosis in Europe by sex, country, age, period and histology. MethodsData from 87 cancer registries in 29 countries were extracted from the EUROCARE-5 dataset. One- and 5-year RS were estimated using the cohort approach for 86,690 adult TC patients diagnosed in 2000–2007 and followed-up to 12/31/2008. RS trends in 1999–2007 and 10-year RS in 2005–2007 were estimated using the period approach. ResultsIn Europe 2000–2007, 5-year RS after TC was 88% in women and 81% in men. Survival rates varied by country and were strongly correlated (Pearson ρ = 75%) with country-specific incidence rates. Five-year RS decreased with age (in women from >95% at age 15–54 to 57% at age 75+), from 98% in women and 94% in men with papillary TC to 14% in women and 12% in men with anaplastic TC. Proportion of papillary TC varied by country and increased over time, while survival rates were similar across areas and periods. In 1999–2007, 5-year RS increased by five percentage points for all TCs but only by two for papillary and by four for follicular TC. Ten-year RS in 2005–2007 was 89% in women and 79% in men. ConclusionsThe reported increasing TC survival trend and differences by area are mainly explained by the varying histological case-mix of cases.

Retinal detachment surgery in Western Australia (2000–2013): a whole-population study

AimsTo determine the background incidence rate of retinal detachment (RD) in Western Australia (WA) between 2000 and 2013, identify sociodemographic features associated with increased risk of incident RD and examine...

Methodological choices affect cancer incidence rates: a cohort study

BackgroundIncidence rates are fundamental to epidemiology, but their magnitude and interpretation depend on methodological choices. We aimed to examine the extent to which the definition of the study population affects cancer incidence rates.MethodsAll primary cancer diagnoses in Sweden between 1958 and 2010 were identified from the national Cancer Register. Age-standardized and age-specific incidence rates of 29 cancer subtypes between 2000 and 2010 were calculated using four definitions of the study population: persons resident in Sweden 1) based on general population statistics; 2) with no previous subtype-specific cancer diagnosis; 3) with no previous cancer diagnosis except non-melanoma skin cancer; and 4) with no previous cancer diagnosis of any type. We calculated absolute and relative differences between methods.ResultsAge-standardized incidence rates calculated using general population statistics ranged from 6% lower (prostate cancer, incidence rate difference: -13.5/100,000 person-years) to 8% higher (breast cancer in women, incidence rate difference: 10.5/100,000 person-years) than incidence rates based on individuals with no previous subtype-specific cancer diagnosis. Age-standardized incidence rates in persons with no previous cancer of any type were up to 10% lower (bladder cancer in women) than rates in those with no previous subtype-specific cancer diagnosis; however, absolute differences were <5/100,000 person-years for all cancer subtypes.ConclusionsFor some cancer subtypes incidence rates vary depending on the definition of the study population. For these subtypes, standardized incidence ratios calculated using general population statistics could be misleading. Moreover, etiological arguments should be used to inform methodological choices during study design.

Incidence, recurrence, and long-term survival of ischemic stroke subtypes: A population-based study in the Middle East.

Background Incidence, risk factors, case fatality and survival rates of ischemic stroke subtypes are unknown in the Middle East due to the lack of community-based incidence stroke studies in this region. Aim To characterize ischemic stroke subtypes in a Middle Eastern population. Methods The Mashad Stroke Incidence Study is a community-based study that prospectively ascertained all cases of stroke among the 450,229 inhabitants of Mashhad, Iran between 2006 and 2007. We identified 512 cases of first-ever ischemic stroke [264 men (mean age 65.5 ± 14.4) and 248 women (mean age 64.14 ± 14.5)]. Subtypes of ischemic stroke were classified according to the TOAST criteria. Incidence rates were age standardized to the WHO and European populations. Results The proportion of stroke subtypes was distributed as follows: 14.1% large artery disease, 15% cardioembolic, 22.5% small artery disease, 43.9% undetermined and 4.5% other. The greatest overall incidence rates were attributed to undetermined infarction (49.97/100,000) followed by small artery disease (25.54/100,000). Prevalence of hypertension, diabetes and atrial fibrillation differed among ischemic stroke subtypes. Overall, there were 268 (52.34%) deaths and 73 (14.25%) recurrent strokes at five years after incident ischemic stroke, with the greatest risk of recurrence seen in the large artery disease (35.6%) and cardioembolic (35.5%) subgroups. Survival was similar in men and women for each stroke subtype. Conclusions We observed markedly greater incidence rates of ischemic stroke subtypes than in other countries within the Mashad Stroke Incidence Study after age standardization. Our findings should be considered when planning prevention and stroke care services in this region.

EPIDEMIOLOGIC RISK ASSESSMENT OF CHILDREN’S MORBIDITY FROM ENVIRONMENTAL EXPOSURE

The purpose of the work is a comparative characteristic of indicators efficiency of relative epidemiological risk of primary and general incidence in estimating medico-ecological situation and mass non-communicable diseases of the population. To achieve the goals and tasks a retrospective study of the child's incidence in the years 2000-2012 was carried out in the 33 administrative territories of the Irkutsk region based on the statistical reporting (Form №12). The relative risk of primary and general morbidity of all diseases and of 11 separate classes was calculated using regional background incidence rates obtained by the statistics. The intensity degree of medico-ecological situation on the territory was determined by the varied criteria on the basis of sigma - deviations, waviness and tendencies of dynamics development of incidence relative risks in time were revealed by a smoothed method of sliding simple average values for 3 years and according to polynomial approximation of the 5th order. The research was carried out in 5 cities with the developed industry and 5 nonindustrial areas. The analysis of the average, increased and high risk rates of the general and primary diseases incidence of separate classes in children during the considered period on the territory of the industrial cities and nonindustrial areas has shown that we gain a better understanding about a degree of medico-ecological situation intensity in the studied territories when sharing risk indicators of the general and primary incidence. Undulating risk dynamics of general and primary morbidity in the period under review differ depending on the area, the class of illnesses and morbidity. This reflects the particular cyclical fluctuations of states with respect to low and high resistance to the pathogenic factor effects. Joint use of the risk indicators of primary and general child's morbidity is necessary to carry out while analyzing data of social and hygiene monitoring to assess the intensity degree of medical and ecological situation and mass (with higher and high risk levels) non-communicable morbidity.

Epidemiology of intussusception in New Zealand pre rotavirus vaccination

To describe the epidemiology of intussusception in New Zealand children aged 0-36 months prior to the introduction of routine rotavirus vaccination.ICD-10 coding data from the New Zealand National Minimum Data Set (NMDS) was used to identify all cases of intussusception in children aged 0-36 months between January 1998 and December 2013. These data were linked with birth data from the New Zealand census. Population incidence rates of intussusception were calculated, and demographic characteristics described.Over the 16-year study period, there were 794 cases of intussusception. The majority (56%) occurred in the first year of life (age adjusted incidence rate 56.1/100,000 child-years, 95% confidence interval (CI) 41.7-71.2). Intussusception occurred more frequently in males (36.4/100,000 (95% CI 24.6-48.2) versus 19.5/100,000 (95% CI 10.8-28.1, p<0.001)). There was no difference in intussusception incidence between ethnic groups, although cases occurred at a younger age in Māori and Pacific infants compared to Asian and other ethnicities (Pacific median 7.5 months (interquartile range 5.9-11.6), Māori 7.8 months (IQR 5.5-12.3), European 9.2 months (IQR 5.8-15.8), Other Ethnicity 10.2 months (IQR 8.2-12.3), Asian 10.5 months (IQR 7.0-17.1 )). There was a weak seasonal trend with incidence troughs in January and July, and corresponding peaks in March and September. There was wide variation in presentation rates across District Health Board (DHB) regions, with a national average of 18.0/100,000 child-years (95% CI 9.7-26.3). Most patients were admitted on a single occasion to a single hospital for treatment (81%).This study updates background incidence rates of intussusception prior to the introduction of a national rotavirus vaccination programme in July 2014. It identifies a trend of earlier intussusception in Māori and Pacific infants; the relationship between earlier intussusception and the risk of vaccine-associated events is unknown.

Bayesian Estimation and Testing in Random Effects Meta-Analysis of Rare Binary Adverse Events

Meta-analysis has been widely applied to rare adverse event data because it is very difficult to reliably detect the effect of a treatment on such events in an individual clinical study. However, it is known that standard meta-analysis methods are often biased, especially when the background incidence rate is very low. A recent work by Bhaumik et al. proposed new moment-based approaches under a natural random effects model, to improve estimation and testing of the treatment effect and the between-study heterogeneity parameter. It has been demonstrated that for rare binary events, their methods have superior performance to commonly used meta-analysis methods. However, their comparison does not include any Bayesian methods, although Bayesian approaches are a natural and attractive choice under the random-effects model. In this article, we study a Bayesian hierarchical approach to estimation and testing in meta-analysis of rare binary events using the random effects model in Bhaumik et al. We develop Bayesian estimators of the treatment effect and the heterogeneity parameter, as well as hypothesis testing methods based on Bayesian model selection procedures. We compare them with the existing methods through simulation. A data example is provided to illustrate the Bayesian approach as well.

The Epidemiology of Hip and Major Osteoporotic Fractures in a Dutch Population of Community-Dwelling Elderly: Implications for the Dutch FRAX® Algorithm.

BackgroundIncidence rates of non-hip major osteoporotic fractures (MOF) remain poorly characterized in the Netherlands. The Dutch FRAX® algorithm, which predicts 10-year probabilities of hip fracture and MOF (first of hip, humerus, forearm, clinical vertebral), therefore incorporates imputed MOF rates. Swedish incidence rate ratios for hip fracture to MOF (Malmo 1987–1996) were used to perform this imputation. However, equality of these ratios between countries is uncertain and recent evidence is scarce. Aims were to estimate incidence rates of hip fracture and MOF and to compare observed MOF rates to those predicted by the imputation method for the Netherlands.MethodsUsing hospitalisation and general practitioner records from the Dutch PHARMO Database Network (2002–2011) we calculated age-and-sex-specific and age-standardized incidence rates (IRs) of hip and other MOFs (humerus, forearm, clinical vertebral) and as used in FRAX®. Observed MOF rates were compared to those predicted among community-dwelling individuals ≥50 years by the standardized incidence ratio (SIR; 95% CI).ResultsAge-standardized IRs (per 10,000 person-years) of MOF among men and women ≥50 years were 25.9 and 77.0, respectively. These numbers were 9.3 and 24.0 for hip fracture. Among women 55–84 years, observed MOF rates were significantly higher than predicted (SIR ranged between 1.12–1.50, depending on age). In men, the imputation method performed reasonable.ConclusionObserved MOF incidence was higher than predicted for community-dwelling women over a wide age-range, while it agreed reasonable for men. As miscalibration may influence treatment decisions, there is a need for confirmation of results in another data source. Until then, the Dutch FRAX® output should be interpreted with caution.

Pharmacoepidemiological considerations in observed-to-expected analyses for vaccines.

Observed‐to‐expected (OE) analyses, together with data mining algorithms1, 2, 3, 4, 5, 6, 7 and pharmacoepidemiological studies,8 are part of the quantitative pharmacovigilance toolkit for vaccines. While data mining algorithms generate hypotheses about potential safety concerns and pharmacoepidemiological studies test specific hypotheses or measure associations, OE analyses stand in between. The role of OE analyses is to refine previously detected signals when there is not enough information to determine whether further action is necessary. In this paper, the focus is on the OE analyses of spontaneous reports, where the observed number of cases is obtained from a spontaneous reporting system and compared with the expected number of cases calculated based on background incidence rates from independent sources, such as epidemiological studies or national statistics. Note that disproportionality data mining algorithms estimate an “OE ratio” generated based on expected and observed numbers of cases from a single spontaneous reporting system. The key requirements and statistical methods recommended for OE analyses are described in European guidelines.9, 10 Here, we discuss in more detail how to perform the analysis and deal with uncertainties. Although described here in the context of vaccines, the methodology and recommendations are in principle also applicable for other medicinal products, but additional complexities would then have to be considered. We will not discuss the use of OE analyses for sequential monitoring, which has been described elsewhere.11, 12

Repurposing historical control clinical trial data to provide safety context

Billions of dollars spent, millions of subject-hours of clinical trial experience and an abundance of archived study-level data, yet why are historical data underutilized? We propose that historical data can be aggregated to provide safety, background incidence rate and context to improve the evaluation of new medicinal products. Here, we describe the development and application of the eControls database, which is derived from the control arms of studies of licensed products, and discuss the challenges and potential solutions to the proper application of historical data to help interpret product safety.

Incidence of Narcolepsy in Germany.

Following the 2009 pandemic, reports of an association between an AS03 adjuvanted H1N1 pandemic influenza vaccine and narcolepsy were published. Besides determining background incidence rates for narcolepsy in Germany this study aimed at investigating whether there was a change in incidence rates of narcolepsy between the pre-pandemic, pandemic, and the post-pandemic period on the population level. Retrospective epidemiological study on the incidence of narcolepsy with additional capture-recapture analysis. German sleep centers. Eligible were patients with an initial diagnosis of narcolepsy (ICD10 Code G47.4) within the period from January 1, 2007 to December 31, 2011. None; observational study. A total of 342 sleep centers were invited to participate in the study. Adequate and suitable data were provided by 233 sleep centers (68.1%). A total of 1,198 patients with an initial diagnosis of narcolepsy within the observed period were included, of whom 106 (8.8%) were children and adolescents under the age of 18 years and 1,092 (91.2%) were adults. In children and adolescents, the age-standardized adjusted incidence rate significantly increased from 0.14/100,000 person-years in the pre-pandemic period to 0.50/100,000 person-years in the post-pandemic period (incidence density ratio, IDR 3.57; 95% CI 1.94-7.00). In adults, no significant change was detectable. This increase started in spring 2009. For the years 2007-2011, valid estimates for the incidence of narcolepsy in Germany were provided. In individuals under 18, the incidence rates continuously increased from spring 2009.

Occurrence of adverse events among patients with inflammatory bowel disease in the HealthCore Integrated Research Database

Objectives:Inflammatory bowel disease (IBD) is a chronic condition commonly requiring lifelong care. Both IBD and IBD-related treatments can cause significant morbidity, and it is often difficult to differentiate their relative etiologic contribution to adverse events (AEs). The objectives of this study were to assess the rates of select AEs among patients with IBD as a function of disease severity and of the use of anti-tumor necrosis factor alpha (anti-TNFα) medications.Methods:We conducted a retrospective cohort study of IBD patients in the HealthCore Integrated Research Database (HIRDTM) between January 2004 and January 2011 to determine rates of AEs in patients with mild and moderate to severe IBD. Key study endpoints were select prespecified malignant neoplasms, infections, and other AEs of interest.Results:A total of 33,386 IBD patients (52.7% ulcerative colitis; 47.3% Crohn's disease) met the inclusion criteria, and 60% had been followed for ≥1 year. Patients with moderate to severe IBD had increased rates of infections, lymphatic and digestive tract cancers, gastrointestinal (GI) perforations, and myocardial infarctions versus patients with mild IBD. Patients with IBD who used anti-TNFα therapies during the study had increased incidence of many types of infections, certain GI cancers (including rectal and anal cancer), intestinal perforations, and kidney stones compared with patients who had never used anti-TNFα therapies.Conclusions:Results from this large US cohort provide descriptive information on AE rates in a population of IBD patients undergoing routine care, estimating background incidence rates of AEs that are not readily available in the published literature. Our study findings may be limited owing to a lack of generalizability and potential for misclassification due to reliance on medical diagnosis and treatment and procedure codes to identify disease, comorbidities, and treatments. Further research and validation of our findings in other populations and databases are needed.

The incidence of childhood and adolescent seizures in the UK from 1999 to 2011: A retrospective cohort study using the Clinical Practice Research Datalink

BackgroundIn postmarketing vaccine surveillance, adverse events observed in a vaccinated population are compared to the number expected based on a background incidence rate. The background rate should be accurate and obtained from a population comparable to the one vaccinated. Such rates are often not available. MethodsThe incidence rate of generalised convulsive, febrile and afebrile seizures was estimated in individuals born after 01-January-1998 and aged between 2 months and 15 years of age using the UK Clinical Practice Research Datalink (1999–2011). ResultsThe study population consisted of 1532,992 individuals (4917,369 person years (PY) of follow up). A total of 28,917 generalised convulsive seizure events were identified during follow-up, the overall incidence rate was 5.88 per 1000PY. Age specific rates increased sharply from 4/1000PY at 2 months of age, peaked at 19/1000PY at 16 months and decreased until approximately 6 years of age at which point they became relatively stable at 2/1000PY. 67% of GCSs were categorised as febrile: 56% using Read codes, 11% using free text. Febrile seizures accounted for the age trend in GCS, with rates peaking at 16.1/1000PY at 16 months of age while afebrile seizure rates remained relatively stable across all ages (24 seizures per 1000PY). Analysis by first occurrence of febrile seizure showed a similar pattern, comparable to published studies on the incidence of seizures in childhood. DiscussionThe rates reported in this study could be used in the postmarketing surveillance of infant vaccines. However, given the variation across strata, and the potential underascertainment of seizure events presenting to A&E, care must be taken when interpreting and using these rates.

Incidence of narcolepsy before and after MF59-adjuvanted influenza A(H1N1)pdm09 vaccination in South Korean soldiers

BackgroundPrevious reports mostly from Europe suggested an association between an occurrence of narcolepsy and an influenza A(H1N1)pdm09 vaccine adjuvanted with AS03 (Pandemrix®). During the 2009 H1N1 pandemic vaccination campaign, the Korean military performed a vaccination campaign with one type of influenza vaccine containing MF59-adjuvants. This study was conducted to investigate the background incidence rate of narcolepsy in South Korean soldiers and the association of the MF59-adjuvanted vaccine with the occurrence of narcolepsy in a young adult group. MethodsTo assess the incidence of narcolepsy, we retrospectively reviewed medical records of suspicious cases of narcolepsy in 2007–2013 in the whole 20 military hospitals of the Korean military. The screened cases were classified according to the Brighton Collaboration case definition of narcolepsy. After obtaining the number of confirmed cases of narcolepsy per 3 months in 2007–2013, we compared the crude incidence rate of narcolepsy before and after the vaccination campaign. ResultsWe included 218 narcolepsy suspicious cases in the initial review, which were screened by the diagnostic code on the computerized disease registry in 2007–2013. Forty-one cases were finally diagnosed with narcolepsy in 2007–2013 (male sex, 95%; median age, 21 years). The average background incidence rate of narcolepsy in Korean soldiers was 0.91 cases per 100,000 persons per year. During the 9 months before vaccination implementation (April to December 2009), 6 narcolepsy cases occurred, whereas during the next 9 months (January to September 2010) including the 3-month vaccination campaign, 5 cases occurred. ConclusionsThe incidence of narcolepsy in South Korean soldiers was not increased after the pandemic vaccination campaign using the MF59-adjuvanted vaccine. Our results suggest that the MF59-adjuvanted H1N1 vaccine did not contribute to the occurrence of narcolepsy in this young adult group.

Acculturation, Behavioral Factors, and Family History of Breast Cancer among Mexican and Mexican-American Women

BackgroundIncidence rates for breast cancer are higher among Mexican-American (MA) women in the United States than women living in Mexico. Studies have shown higher prevalence of breast cancer risk factors in more acculturated than less acculturated Hispanic/Latinas in the United States. We compared the prevalence of behavioral risk factors and family history of breast cancer by level of acculturation and country of residence in women of Mexican descent. MethodsData were collected from 1,201 newly diagnosed breast cancer patients living in Mexico (n = 581) and MAs in the United States (n = 620). MA participants were categorized into three acculturation groups (Spanish dominant, bilingual, and English dominant); women living in Mexico were used as the referent group. The prevalence of behavioral risk factors and family history of breast cancer were assessed according to acculturation level, adjusting for age at diagnosis and education. ResultsIn the adjusted models, bilingual and English-dominant MAs were significantly more likely to have a body mass index of 30 kg/m2 or greater, consume more than one alcoholic beverage a week, and report having a family history of breast cancer than women living in Mexico. All three U.S. acculturation groups were significantly more likely to have lower total energy expenditure (≤533 kcal/d) than women in Mexico. English-dominant women were significantly less likely to ever smoke cigarettes than the Mexican group. ConclusionsOur findings add to the limited scientific literature on the relationships among acculturation, health behavior, and family history of breast cancer in Mexican and MA women.

Investigating Reports of Complex Regional Pain Syndrome: An Analysis of HPV-16/18-Adjuvanted Vaccine Post-Licensure Data

Complex regional pain syndrome (CRPS) is a chronic pain disorder that typically follows trauma or surgery. Suspected CRPS reported after vaccination with human papillomavirus (HPV) vaccines led to temporary suspension of proactive recommendation of HPV vaccination in Japan. We investigated the potential CRPS signal in relation to HPV-16/18-adjuvanted vaccine (Cervarix®) by database review of CRPS cases with independent expert confirmation; a disproportionality analysis and analyses of temporality; an observed versus expected analysis using published background incidence rates; systematic reviews of aggregate safety data, and a literature review.The analysis included 17 case reports of CRPS: 10 from Japan (0.14/100,000 doses distributed) and seven from the United Kingdom (0.08/100,000). Five cases were considered by independent experts to be confirmed CRPS. Quantitative analyses did not suggest an association between CRPS and HPV-16/18-adjuvanted vaccine. Observed CRPS incidence after HPV-16/18 vaccination was statistically significantly below expected rates. Systematic database reviews using search terms varying in specificity and sensitivity did not identify new cases. No CRPS was reported during clinical development and no unexpected results found in the literature.There is not sufficient evidence to suggest an increased risk of developing CRPS following vaccination with HPV-16/18-adjuvanted vaccine. Post-licensure safety surveillance confirms the acceptable benefit-risk of HPV-16/18 vaccination.

Estimates of over-diagnosis of breast cancer due to population-based mammography screening in South Australia after adjustment for lead time effects

To estimate over-diagnosis due to population-based mammography screening using a lead time adjustment approach, with lead time measures based on symptomatic cancers only. Women aged 40-84 in 1989-2009 in South Australia eligible for mammography screening. Numbers of observed and expected breast cancer cases were compared, after adjustment for lead time. Lead time effects were modelled using age-specific estimates of lead time (derived from interval cancer rates and predicted background incidence, using maximum likelihood methods) and screening sensitivity, projected background breast cancer incidence rates (in the absence of screening), and proportions screened, by age and calendar year. Lead time estimates were 12, 26, 43 and 53 months, for women aged 40-49, 50-59, 60-69 and 70-79 respectively. Background incidence rates were estimated to have increased by 0.9% and 1.2% per year for invasive and all breast cancer. Over-diagnosis among women aged 40-84 was estimated at 7.9% (0.1-12.0%) for invasive cases and 12.0% (5.7-15.4%) when including ductal carcinoma in-situ (DCIS). We estimated 8% over-diagnosis for invasive breast cancer and 12% inclusive of DCIS cancers due to mammography screening among women aged 40-84. These estimates may overstate the extent of over-diagnosis if the increasing prevalence of breast cancer risk factors has led to higher background incidence than projected.

Perceived need for HIV testing among rural and urban African American cocaine users

Background Incidence rates of HIV continue to be disproportionately high among African Americans compared to other races, especially in the South. Although we have some information about testing among African Americans, most surveys do not include homeless, impoverished, or other disenfranchised and therefore hard-to-reach groups, many of whom may be particularly high-risk for HIV infection, and few studies have compared HIV testing among rural and urban African Americans. The purpose of this study, therefore, is to address this gap by systematically examining perceived need for HIV testing among rural as compared to urban African American cocaine users. Methods This is a cross-sectional, community-based study of 400 not-in-treatment African American cocaine users residing in selected rural and urban areas of Arkansas. We used respondent-driven sampling methods to fill our sample. Face-to-face computer-assisted interviews were conducted in study offices lasting 1½ – 2 hours. A logistic regression model was used to examine the association between perceived need for HIV testing and rural/ urban residence, while controlling for demographic and clinical characteristics. Covariates in the model included: demographics (age, gender, education, health insurance), clinical characteristics (lifetime drug abuse treatment, lifetime mental health treatment, routine health-care visit in past year, general health status, ever being tested for hepatitis C or gonorrhea, number of times tested for HIV), access factors (ease of access to HIV testing, availability of HIV testing, skepticism towards medical care, stigma for HIV testing) and behavioral risk factors (perceived risk of acquiring HIV, number of sex partners, inconsistent condom use, ever trading sex for foods or drugs). Results We did not find significant differences among rural and urban African American cocaine users’ perceived need for HIV testing. Female gender, perceived risk for acquiring HIV, stigma, and receipt of testing for other sexually transmitted diseases were each positively and significantly related to perceived need to be tested for HIV in multivariate regression analysis in which all other variables were held constant. Receipt of routine medical care in the past year, being tested for HIV from 3–5 times, and skepticism towards medical care were negatively and significantly related to perceived need for HIV testing. Behavioral risk factors or general health status were not significantly associated with perceived need for HIV testing. Access to testing was not perceived as a significant barrier to testing. Conclusions

Incidence of microscopic colitis in the Netherlands. A nationwide population-based study from 2000 to 2012

BackgroundIncidence rates of microscopic colitis are mainly based on regional data from a limited number of countries. To evaluate geographical differences and changes over time, more nationwide incidence rates are needed. AimsThe aim of this retrospective study was to assess the incidence rate of microscopic colitis in the Netherlands in a nationwide cohort. MethodsA search was performed in the Dutch pathology registry, covering records of all approximately 16.5 million inhabitants. Incident cases were defined as a first diagnosis of microscopic colitis (collagenous or lymphocytic colitis) between 2000 and 2012. ResultsIn total, 7228 incident cases were identified with a mean annual incidence rate of 3.4 per 100,000 person years. Collagenous colitis was present in 3741 cases and lymphocytic colitis in 2718 cases, with a mean annual incidence rate of 1.8 and 1.3 per 100,000 person years, respectively. Remaining 769 cases were described as undefined microscopic colitis. Collagenous and lymphocytic colitis incidence rates increased significantly over time (p<0.001) with a male:female ratio of 1:3 and 1:2, respectively. ConclusionThe Dutch mean annual incidence rates of collagenous and lymphocytic colitis were considerably lower than previously reported by other countries. However, incidence rates increased gradually over time, with a clear female predominance.