Academic impact of a public electronic health database: bibliometric analysis of studies using the general practice research database

Literature Review of Studies Using the National Database of the Health Insurance Claims of Japan (NDB): Limitations and Strategies in Using the NDB for Research

The use of the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) for research has increased over time. Researchers need to understand the characteristics of the data to generate quality-assured evidence from the NDB. In this review, we mapped and characterized the limitations and related strategies using the NDB for research based on the descriptions of published NDB studies. To find studies that used Japanese healthcare claims data, we searched MEDLINE, EMBASE, and Ichushi-Web up to June 2023. Additionally, we hand-searched the NDB data publication list from the Ministry of Health, Labour and Welfare (2017-2023). We abstracted data based on the NDB data type, research themes, age of the study sample or population, targeted disease, and the limitations and strategies in the NDB studies. Ultimately, 267 studies were included. Overall, the most common research theme was describing and estimating the prescriptions and treatment patterns (125 studies, 46.8%). There was a variation in the frequency of themes according to the type of NDB data. We identified the following categories of limitations: (1) lack of information on confounders/covariates, outcomes, and other clinical content, (2) limitations regarding patients not included in the NDB, (3) misclassification of data, (4) lack of unique identifiers and register of beneficiaries, and (5) others. Although the included studies noted several limitations of using the NDB for research, they also provided some strategies to address them. Organizing the limitations of NDB in research and the related strategies across research fields can help support high-quality NDB studies.

A Review of Studies Using Japanese Nationwide Administrative Claims Databases

BACKGROUND

Administrative claims databases are increasingly being used worldwide for research purposes. We reviewed original published articles that used one of the four nationwide administrative claims databases in Japan: the National Database of Health Insurance Claims and Specific Health Checkups (NDB), NDB Open Data, the JMDC Claims Database, and the Diagnosis Procedure Combination (DPC) database.

METHODS

Studies published from January 2010 to July 2022 using the JMDC and DPC databases, and from January 2013 to July 2022 using the NDB and NDB Open Data were identified using PubMed. The number of original articles was divided into 19 fields. The annual growth rate of the number of studies was calculated using the four databases.

RESULTS

Overall, 1047 studies were included (95 for the NDB, 31 for the NDB Open Data, 222 for the JMDC database, and 699 for the DPC databases). Studies using one of these four databases increased from around 2010, and the average annual growth rate was approximately 41% from 2010 to 2021. DPC database studies had a higher proportion of articles on surgery (19.2%), urology (3.0%), neurosurgery (6.2%), anesthesiology (1.9%), and emergency medicine (14.0%), whereas the NDB and JMDC data had higher proportions of those regarding internal medicine.

CONCLUSIONS

Since 2010, these four databases have increasingly attracted attention, and the number of studies using them has grown rapidly. Our review suggests that each has unique features, and researchers should understand the database characteristics to operate their studies.

Findability of UK health datasets available for research: a mixed methods study

OBJECTIVE

How health researchers find secondary data to analyse is unclear. We sought to describe the approaches that UK organisations take to help researchers find data and to assess the findability of health data that are available for research.

METHODS

We surveyed established organisations about how they make data findable. We derived measures of findability based on the first element of the FAIR principles (Findable, Accessible, Interoperable, Reproducible). We applied these to 13 UK health datasets and measured their findability via two major internet search engines in 2018 and repeated in 2021.

RESULTS

Among 12 survey respondents, 11 indicated that they made metadata publicly available. Respondents said internet presence was important for findability, but that this needed improvement. In 2018, 8 out of 13 datasets were listed in the top 100 search results of 10 searches repeated on both search engines, while the remaining 5 were found one click away from those search results. In 2021, this had reduced to seven datasets directly listed and one dataset one click away. In 2021, Google Dataset Search had become available, which listed 3 of the 13 datasets within the top 100 search results.

DISCUSSION

Measuring findability via online search engines is one method for evaluating efforts to improve findability. Findability could perhaps be improved with catalogues that have greater inclusion of datasets, field-level metadata and persistent identifiers.

CONCLUSION

UK organisations recognised the importance of the internet for finding data for research. However, health datasets available for research were no more findable in 2021 than in 2018.

Stakeholders’ Consumption of Agricultural Injury Reports from News Media: A Six-Year Analysis of Website Usage and Visitor Analytics

AgInjuryNews.org is a news report-based, online sentinel surveillance dataset that has provided publicly available news and media reports of agricultural injuries since early 2015. In the 6 years since its inception, AgInjuryNews.org has hosted 12,897 unique visitors and has collected 997 user account registrations. New users from geographic areas home to NIOSH-funded agricultural research centres were most prominent, with these centres returning in larger numbers, comparatively. Users were acquired mostly through web searches, collaborations with other agencies, and paid Facebook.com advertisements. Paid advertisements recruited 3792 visitors; however, retention, registrations, and on-site engagement from this source was low. This analysis shows that data consumption on AgInjuryNews.org is steadily growing. Similar self-hosted programs that provide data or digital resources to agricultural safety and health stakeholders should consider the integration of auditing and analytics tracking, including user registrations.

Long-Term Risk of Autoimmune Diseases other than Systemic Lupus Erythematosus in Cutaneous Lupus Erythematosus-Alone Patients: A 10-Year Nationwide Cohort Study

BACKGROUND

Up to 25% of patients with cutaneous lupus erythematosus (CLE) can develop systemic lupus erythematosus (SLE). However, the risk of autoimmune diseases other than SLE in CLE patients who have only skin manifestations (CLE-alone) has rarely been explored.

OBJECTIVE

To investigate the long-term risk and independent factors of non-SLE autoimmune diseases among CLE-alone patients.

METHOD

A nationwide cohort study using the Taiwanese National Health Insurance Research Database 1997-2013. CLE patients and matched subjects were included. Cumulative incidences of autoimmune diseases after 1 year of CLE-alone diagnosis were compared. Cox proportional hazard model was also performed.

RESULTS

A total of 971 CLE-alone patients and 5,175 reference subjects were identified. The 10-year cumulative incidence of autoimmune diseases other than SLE was significantly elevated in the CLE-alone cohort (9.00%, 95% confidence interval [CI] 6.72-11.29) than in the reference cohort (4.20%, 95% CI 3.53-4.87%) (p < 0.001). CLE-alone was independently associated with non-SLE autoimmune diseases (adjusted hazard ratio 1.55, 95% CI 1.10-2.18). Among CLE-alone patients, females and those taking long-term systemic corticosteroids (a proxy for extensive disease) were associated with non-SLE autoimmune diseases after adjusting for the number of repeated autoimmune laboratory tests.

CONCLUSION

CLE-alone is independently associated with future non-SLE autoimmune diseases.

The National ReferAll Database: An Open Dataset of Exercise Referral Schemes Across the UK

In 2014, The National Institute for Health and Care Excellence (NICE) called for the development of a system to collate local data on exercise referral schemes (ERS). This database would be used to facilitate continued evaluation of ERS. The use of health databases can spur scientific investigation and the generation of evidence regarding healthcare practice. NICE’s recommendation has not yet been met by public health bodies. Through collaboration between ukactive, ReferAll, a specialist in software solutions for exercise referral, and the National Centre for Sport and Exercise Medicine, which has its research hub at the Advanced Wellbeing Research Centre, in Sheffield, data has been collated from multiple UK-based ERS to generate one of the largest databases of its kind. This database moves the research community towards meeting NICEs recommendation. This paper describes the formation and open sharing of The National ReferAll Database, data-cleaning processes, and its structure, including outcome measures. Collating data from 123 ERSs on 39,283 individuals, a database has been created containing both scheme and referral level characteristics in addition to outcome measures over time. The National ReferAll Database is openly available for researchers to interrogate. The National ReferAll Database represents a potentially valuable resource for the wider research community, as well as policy makers and practitioners in this area, which will facilitate a better understanding of ERS and other physical-activity-related social prescribing pathways to help inform public health policy and practice.

Two Decades of Research Using Taiwan's National Health Insurance Claims Data: Bibliometric and Text Mining Analysis on PubMed

Background

Studies using Taiwan’s National Health Insurance (NHI) claims data have expanded rapidly both in quantity and quality during the first decade following the first study published in 2000. However, some of these studies were criticized for being merely data-dredging studies rather than hypothesis-driven. In addition, the use of claims data without the explicit authorization from individual patients has incurred litigation.

Objective

This study aimed to investigate whether the research output during the second decade after the release of the NHI claims database continues growing, to explore how the emergence of open access mega journals (OAMJs) and lawsuit against the use of this database affect the research topics and publication volume and to discuss the underlying reasons.

Methods

PubMed was used to locate publications based on NHI claims data between 1996 and 2017. Concept extraction using MetaMap was employed to mine research topics from article titles. Research trends were analyzed from various aspects, including publication amount, journals, research topics and types, and cooperation between authors.

Results

A total of 4473 articles were identified. A rapid growth in publications was witnessed from 2000 to 2015, followed by a plateau. Diabetes, stroke, and dementia were the top 3 most popular research topics whereas statin therapy, metformin, and Chinese herbal medicine were the most investigated interventions. Approximately one-third of the articles were published in open access journals. Studies with two or more medical conditions, but without any intervention, were the most common study type. Studies of this type tended to be contributed by prolific authors and published in OAMJs.

Conclusions

The growth in publication volume during the second decade after the release of the NHI claims database was different from that during the first decade. OAMJs appeared to provide fertile soil for the rapid growth of research based on NHI claims data, in particular for those studies with two or medical conditions in the article title. A halt in the growth of publication volume was observed after the use of NHI claims data for research purposes had been restricted in response to legal controversy. More efforts are needed to improve the impact of knowledge gained from NHI claims data on medical decisions and policy making.

The Evolution of Publication Hotspots in Electronic Health Records from 1957 to 2016 and Differences Among Six Countries

This study aims to reveal the evolution of publication hotspots in the field of electronic health records (EHRs) and differences among countries. We applied keyword frequency analysis, keyword co-occurrence analysis, principal component analysis, multidimensional scaling analysis, and visualization technology to compare the high-frequency Medical Subject Heading (MeSH) terms in six countries during the periods 1957-2008 and 2009-2016. After 2009, the number of MeSH terms reflecting information exchange and information mining increased, and various types of evaluations based on EHRs and cohort studies significantly increased. The top 20 MeSH terms between 2009 and 2016 constitute five relatively larger knowledge groups. Thus, we conclude that publication hotspots in EHR field have shifted from issues related to the adoption of EHRs to the utilization of EHRs, and the knowledge structure has become systematic. The publication's focus was different in the six countries, which may relate to their national characteristics.

A systematic investigation on the research publications that have used the medical expenditure panel survey (MEPS) data through a bibliometrics approach

Purpose

This study aimed to examine how Medical Expenditure Panel Survey (MEPS) data have been used to support scientific discoveries in biomedical and health sciences, and provide insight to researchers who are interested in using MEPS regarding collaborations and dissemination of research output.

Design/methodology/approach

A bibliometric approach was used to systematically examine the publications that used MEPS data and were indexed by PubMed and Web of Science (WoS). Microsoft Excel and bibliometric tools (WoS and VOSviewer) were utilized for quantitative and bibliometric network analysis. The measures were investigated on the total number of publications by year, research categories, source journals, other datasets/databases co-used with MEPS, funding sources, collaboration patterns, and research topics.

Findings

A total of 1,953 eligible publications were included in this study with the numbers growing significantly over time. MEPS data were primarily used in healthcare services, public environmental and occupational health research. The journals that published the most papers using MEPS were all in the healthcare research area. Twenty-four other databases were found to be used along with MEPS. Over 3,200 researchers from 1,074 institutions in 25 countries have contributed to the publications. Research funding was supported from federal, private, local, and international agencies. Three clusters of research topics were identified among 235 key terms extracted from titles and abstracts.

Originality/value

Our results illustrated the broad landscape of the research efforts that MEPS data have supported and substantiated the value of AHRQ's effort of providing MEPS to the public.

Early Discharged Lumbar Spine Fusion Reduced Postoperative Readmissions: A Retrospective Cohort Study

Early discharge (ED) has emerged and gained popularity in spine surgery. However, the benefits of ED in lumbar fusion have not yet been validated by large cohort studies. To evaluate the effects of ED on readmissions and reoperations in lumbar fusion, this study utilized a national database to enroll patients who had undergone lumbar fusion surgery at age 50–70 years, and grouped them into an ED group or a comparison group. In the comprehensive follow-up of 180 days post-operation, the two groups were compared. There were 18,008 patients in the cohort, including 2172 in the ED group and 15,836 in the comparison group. The ED group was slightly younger (59.9 vs. 60.7 years, p < 0.001), more male predominant (44.9% vs. 36.9%, p < 0.001), and had fewer medical comorbidities. The ED group had less incidences of readmission than the comparison group. (Crude hazard ratio = 0.73, and adjusted HR = 0.75, both p < 0.001). Overall, the cumulative incidences of readmission in the ED group (9.5%) were lower than those in the comparison group (12.8%, p < 0.001), whereas reoperations were insignificantly different (1.5% vs. 1.2%, p = 0.189). For patients aged 50–70 years and who require lumbar fusion surgery, ED could yield a 25% reduced risk of readmission for any cause within 180 days post-operation. Since the reoperation rates remained similar, our results suggest that ED may be a promising option for elderly patients undergoing lumbar spinal fusion surgery.

Natural History of Acromegaly: Incidences, Re-operations, Cancers, and Mortality Rates in a National Cohort

BACKGROUND

Acromegaly is so rare that its natural history, including incidence, risk of cancers, and mortality rates, remains elusive. This natural study utilized a nationwide database to provide a better understanding of acromegaly's disease course.

METHODS

A cohort of 1,195 acromegaly patients were identified and followed-up from 1997 to 2013. Incidence, operation, and re-operation rates were calculated. Excessive mortality and cancer risk related to acromegaly were estimated by standardized mortality ratio (SMR) and standardized incidence ratio (SIR).

RESULTS

The incidence was 2.78 per million-person-years, with little gender predominance (female vs. male, 49.5 vs. 50.5%, respectively). There was female predominance only among 50 and 60 year-olds (incidence rate ratio: 1.37 and 1.43, p < 0.001 and p = 0.002). Among them, 673 (56.3%) had hypophysectomy surgery, and the young-onset (<40 years) patients had more re-operations (15.5%, p = 0.01). The overall mortality rate was 22.3 per 1,000 person-years, with a median survival of 4.67 years (with no gender differences, p = 0.38). The overall SMR of acromegaly patients was 1.41, and the onset-age-specific SMRs of the early- and middle-onset patients were higher than for those with late-onset. There were 87 newly diagnosed cancers in the cohort, with an incidence rate of 10.6 per 1,000 person-years (median 5.4 years). The overall SIR of cancers was 1.91, and there were no differences among gender, onset-age, and disease duration (all SIR >1, approximately 2).

CONCLUSION

Acromegaly is associated with an excessive risk of mortality and two-fold higher risk of cancers. Patients with acromegaly should be managed appropriately after the diagnosis.

Traditional Chinese medicine use is associated with lower end-stage renal disease and mortality rates among patients with diabetic nephropathy: a population-based cohort study

Background

Diabetic nephropathy (DN) is a common complication of diabetes mellitus (DM) that imposes an enormous burden on the healthcare system. Although some studies show that traditional Chinese medicine (TCM) treatments confer a protective effect on DN, the long-term impact remains unclear. This study aims to examine end-stage renal disease (ESRD) and mortality rates among TCM users with DN.

Methods

A total of 125,490 patients with incident DN patients from 2004 to 2006 were identified from the National Health Insurance Research Database in Taiwan and followed until 2012. The landmark method was applied to avoid immortal time bias, and propensity score matching was used to select 1:1 baseline characteristics-matched cohort. The Kaplan–Meier method and competing-risk analysis were used to assess mortality and ESRD rates separately.

Results

Among all eligible subjects, about 60% of patients were classified as TCM users (65,812 TCM users and 41,482 nonusers). After 1:1 matching, the outcomes of 68,882 patients were analyzed. For the ESRD rate, the 8-year cumulative incidence was 14.5% for TCM users [95% confidence interval (CI): 13.9–15.0] and 16.6% for nonusers (95% CI: 16.0–17.2). For the mortality rate, the 8-year cumulative incidence was 33.8% for TCM users (95% CI: 33.1–34.6) and 49.2% for nonusers (95% CI: 48.5–49.9). After adjusting for confounding covariates, the cause-specific hazard ratio of ESRD was 0.81 (95% CI: 0.78–0.84), and the hazard ratio of mortality for TCM users was 0.48 (95% CI: 0.47–0.50). The cumulative incidence of mortality increased rapidly among TCM users with ESRD (56.8, 95% CI: 54.6–59.1) when compared with TCM users without ESRD (30.1, 95% CI: 29.4–30.9). In addition, TCM users who used TCM longer or initiated TCM treatments after being diagnosed with DN were associated with a lower risk of mortality. These results were consistent across sensitivity tests with different definitions of TCM users and inverse probability weighting of subjects.

Conclusions

The lower ESRD and mortality rates among patients with incident DN correlates with the use of TCM treatments. Further studies about specific TCM modalities or medications for DN are still needed.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2491-y) contains supplementary material, which is available to authorized users.

Risk of fracture in transfusion-naïve thalassemia population: A nationwide population-based retrospective cohort study

In thalassemia major or transfusion-dependent thalassemia patients, osteoporosis-related bone complications such as fracture events are common. However, no studies have investigated the risk of fracture in transfusion-naïve thalassemia population. Therefore, we conducted a longitudinal nationwide cohort study to determine whether this population has an increased risk of fracture. This nationwide, population-based cohort study analyzed data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending until the end of 2011. We identified cases with transfusion-naïve thalassemia and selected a comparison cohort that was frequency-matched according to age and year of diagnosis of thalassemia at a ratio of one subject with thalassemia to four subjects in the control group. We analyzed the risk of fracture events to occur in transfusion-naïve thalassemia cases by using Cox proportional hazards regression models. Totally, the study recruited 1369 transfusion-naïve thalassemia subjects and 5416 controls. We identified a total of 71 cases with fracture events within the thalassemia group and 204 within the control group. The overall risks for developing fracture events were 1.35-fold higher in transfusion-naïve thalassemia individuals than the comparison cohort after adjusting for age, sex and comorbidities. Most fracture events were observed in male transfusion-naïve thalassemia individuals rather than the normal population. In subgroup analysis, there was a 1.46-fold higher risk to develop upper-limb fracture in the thalassemia group than in the control groups. In conclusion, our long-term, cohort study results showed that there was a higher risk for the development of fractures in transfusion-naïve thalassemia individuals, particularly in male cases.

Factors influencing the development of primary care data collection projects from electronic health records: a systematic review of the literature

BACKGROUND

Primary care data gathered from Electronic Health Records are of the utmost interest considering the essential role of general practitioners (GPs) as coordinators of patient care. These data represent the synthesis of the patient history and also give a comprehensive picture of the population health status. Nevertheless, discrepancies between countries exist concerning routine data collection projects. Therefore, we wanted to identify elements that influence the development and durability of such projects.

METHODS

A systematic review was conducted using the PubMed database to identify worldwide current primary care data collection projects. The gray literature was also searched via official project websites and their contact person was emailed to obtain information on the project managers. Data were retrieved from the included studies using a standardized form, screening four aspects: projects features, technological infrastructure, GPs' roles, data collection network organization.

RESULTS

The literature search allowed identifying 36 routine data collection networks, mostly in English-speaking countries: CPRD and THIN in the United Kingdom, the Veterans Health Administration project in the United States, EMRALD and CPCSSN in Canada. These projects had in common the use of technical facilities that range from extraction tools to comprehensive computing platforms. Moreover, GPs initiated the extraction process and benefited from incentives for their participation. Finally, analysis of the literature data highlighted that governmental services, academic institutions, including departments of general practice, and software companies, are pivotal for the promotion and durability of primary care data collection projects.

CONCLUSION

Solid technical facilities and strong academic and governmental support are required for promoting and supporting long-term and wide-range primary care data collection projects.

Linked Hospital and Primary Care Database Analysis of the Incidence and Impact of Psychiatric Morbidity Following Gastrointestinal Cancer Surgery in England

OBJECTIVE

To evaluate risk of psychiatric morbidity and its impact on survival in gastrointestinal surgery.

BACKGROUND

Psychiatric morbidity related to surgery is poorly understood, and may be evaluated using linked hospital and primary care data.

METHODS

Patients undergoing gastrointestinal surgery from 2000 to 2011 with linkage of Clinical Practice Research Datalink (CPRD), Hospital Episodes Statistics (HES), Office of National Statistics (ONS), and National Cancer Intelligence Network (NCIN) databases were studied. Psychiatric morbidity was defined as a diagnosis code in CPRD or HES, or a prescription code for psychiatric medication in the 36 months before (preoperative) or 12 months after (postoperative) surgery. Newly diagnosed psychiatric morbidity was measured in patients without preoperative psychiatric morbidity.

RESULTS

In our study, 14,797 (23.8%) and 47,279 (76.2%) patients had surgery for cancer and benign disease, respectively. Postoperative psychiatric morbidity was observed in 10.1% (1500/14797) of patients undergoing cancer surgery. Logistic regression revealed that when adjusted for other factors, cancer diagnosis [odds ratio (OR) = 1.19] independently predicted postoperative psychiatric morbidity (P < 0.05). Hepatopancreaticobiliary resection (OR = 2.40) and esophagogastrectomy (OR = 2.55) carried the highest risks of postoperative psychiatric morbidity (P < 0.05). Preoperative psychiatric morbidity (OR = 1.16) and newly diagnosed psychiatric morbidity (OR = 1.87) were associated with increased 1-year mortality in cancer patients only (P < 0.05).

CONCLUSIONS

Postoperative psychiatric morbidity affected a tenth of patients who underwent gastrointestinal cancer surgery and was associated with increased mortality. Strategies to identify patients at risk preoperatively and to reduce the observed adverse impact of postoperative psychiatric morbidity should be part of perioperative care in complex cancer patients.

Predictive model for 5-year mortality after breast cancer surgery in Taiwan residents

BACKGROUND

Few studies of breast cancer surgery outcomes have used longitudinal data for more than 2 years. This study aimed to validate the use of the artificial neural network (ANN) model to predict the 5-year mortality of breast cancer patients after surgery and compare predictive accuracy between the ANN model, multiple logistic regression (MLR) model, and Cox regression model.

METHODS

This study compared the MLR, Cox, and ANN models based on clinical data of 3632 breast cancer patients who underwent surgery between 1996 and 2010. An estimation dataset was used to train the model, and a validation dataset was used to evaluate model performance. The sensitivity analysis was also used to assess the relative significance of input variables in the prediction model.

RESULTS

The ANN model significantly outperformed the MLR and Cox models in predicting 5-year mortality, with higher overall performance indices. The results indicated that the 5-year postoperative mortality of breast cancer patients was significantly associated with age, Charlson comorbidity index (CCI), chemotherapy, radiotherapy, hormone therapy, and breast cancer surgery volumes of hospital and surgeon (all P < 0.05). Breast cancer surgery volume of surgeon was the most influential (sensitive) variable affecting 5-year mortality, followed by breast cancer surgery volume of hospital, age, and CCI.

CONCLUSIONS

Compared with the conventional MLR and Cox models, the ANN model was more accurate in predicting 5-year mortality of breast cancer patients who underwent surgery. The mortality predictors identified in this study can also be used to educate candidates for breast cancer surgery with respect to the course of recovery and health outcomes.

Survival and complication rates in patients with thalassemia major in Taiwan

BACKGROUND

While transfusion and iron chelation therapy for thalassemia major (TM) has improved dramatically in recent years, the consequences of this improvement (current rates of survival and TM-related complications) remain unknown.

METHODS

This nationwide population-based cohort study analyzed 2007-2011 data obtained from the Taiwanese National Health Insurance Research Database.

RESULTS

After excluding those patients receiving hematopoietic stem cell transplantation, we enrolled 454 patients with TM who received transfusion and chelation therapy (median age, 17.2 years). Among these patients, the mortality rate was 2.9% in 2007, 2.3% in 2008, 2.9% in 2009, 2.6% in 2010, and 0.7% in 2011. Heart was the most common target organ of TM-related complications. There were 80 patients (17.6%) with arrhythmia and 86 patients (18.9%) with congestive heart failure. Dysfunction of endocrine organs was common, and the most common endocrinopathy was hypogonadism (23.1%), followed by diabetes (21.2%). There were 75 patients (16.5%) with liver cirrhosis and 79 patients (17.4%) with osteoporosis.

CONCLUSIONS

Adequate red blood cell transfusion and iron chelation is available to all patients with TM in Taiwan under the universal health insurance system, and has resulted in reduction of TM-related mortality to very low levels. As these patients get older, early detection of complications and adequate intervention are important to quality-of-life improvement.

Management and Risk Reduction of Rheumatoid Arthritis in Individuals with Obstructive Sleep Apnea: A Nationwide Population-Based Study in Taiwan

STUDY OBJECTIVES

To explore associations between obstructive sleep apnea (OSA) and autoimmune diseases and evaluate whether OSA management reduces the incidence of autoimmune diseases.

METHODS

This was a retrospective cohort study using nationwide database research. The data was from 105,846 adult patients in whom OSA was diagnosed and recorded in the Taiwan National Health Insurance Research Database between 2002 and 2011 were the patients were analyzed retrospectively. Patients with antecedent autoimmune diseases were excluded. A comparison cohort of 423,384 participants without OSA served as age- and sex-matched controls. Multivariable Cox regression analysis was performed on both cohorts to compute risk of autoimmune diseases during follow-up. Time-dependent OSA treatment effect was analyzed among patients with OSA. There were no interventions.

RESULTS

Among patients with OSA, overall risk for incident autoimmune diseases was significantly higher than that in controls (adjusted hazard ratio [HR] = 1.95, 95% confidence interval [CI] = 1.66-2.27). Risk for individual autoimmune diseases, including rheumatoid arthritis (RA), Sjögren syndrome (SS), and Behçet disease, was significantly higher in patients with OSA than in controls (HRs [95% CI]: RA 1.33 [1.03-1.72, SS 3.45 [2.67-4.45] and Behçet disease 5.33 [2.45-12.66]). Increased risk for systemic lupus erythematosus (HR 1.00 [0.54-1.84]) and systemic sclerosis (HR 1.43 [0.51-3.96]) did not reach statistical significance. Patients with OSA receiving treatment had an overall reduced risk of RA and other autoimmune diseases (time-dependent HRs [95% CI]: 0.22 [0.05-0.94] and 0.51 [0.28-0.92], respectively).

CONCLUSIONS

Patients with OSA are associated with higher risk for developing RA, SS, and Behçet disease. OSA management is associated with reduced risk of RA.

Steroid dependency and trends in prescribing for inflammatory bowel disease - a 20-year national population-based study

BACKGROUND

It is unclear whether adherence to prescribing standards has been achieved in inflammatory bowel disease (IBD).

AIM

To determine how prescribing of 5-aminosalicylates (5-ASAs), steroids and thiopurines has changed in response to emerging evidence.

METHODS

We examined trends in oral and topical therapies in 23 509 incident IBD cases (6997 with Crohn's disease and 16 512 with ulcerative colitis) using a nationally representative sample between 1990 and 2010. We created five eras according to the year of diagnosis: era 1 (1990-1993), era 2 (1994-1997), era 3 (1998-2001), era 4 (2002-2005) and era 5 (2006-2010). We calculated the proportion of patients treated with prolonged 5-ASAs (>12 months) and steroid dependency, defined as prolonged steroids (>3 months) or recurrent (restarting within 3 months) steroid exposure. We calculated the cumulative probability of receiving each medication using survival analysis.

RESULTS

Half of the Crohn's disease patients were prescribed prolonged oral 5-ASAs during the study, although this decreased between era 3 and 5 from 61.8% to 56.4% (P = 0.002). Thiopurine use increased from 14.0% to 47.1% (P < 0.001) between era 1 and 5. This coincided with a decrease in steroid dependency from 36.5% to 26.8% (P < 0.001) between era 1 and 2 and era 4 and 5 respectively. In ulcerative colitis, 49% of patients were maintained on prolonged oral 5-ASAs. Despite increasing thiopurine use, repeated steroid exposure increased from 15.3% to 17.8% (P = 0.02) between era 1 and 2 and era 4 and 5 respectively.

CONCLUSIONS

Prescribing in clinical practice insufficiently mirrors the evidence base. Physicians should direct management towards reducing steroid dependency and optimising 5-ASA use in patients with IBD.

The snow system: A decentralized medical data processing system

Systems for large-scale reuse of electronic health record data is claimed to have the potential to transform the current health care delivery system. In principle three alternative solutions for reuse exist: centralized, data warehouse, and decentralized solutions. This chapter focuses on the decentralized system alternative. Decentralized systems may be categorized into approaches that move data to enable computations or move computations to the where data is located to enable computations. We describe a system that moves computations to where the data is located. Only this kind of decentralized solution has the capabilities to become ideal systems for reuse as the decentralized alternative enables computation and reuse of electronic health record data without moving or exposing the information to outsiders. This chapter describes the Snow system, which is a decentralized medical data processing system, its components and how it has been used. It also describes the requirements this kind of systems need to support to become sustainable and successful in recruiting voluntary participation from health institutions.

Calculating Total Health Service Utilisation and Costs from Routinely Collected Electronic Health Records Using the Example of Patients with Irritable Bowel Syndrome Before and After Their First Gastroenterology Appointment

INTRODUCTION

Health economic models are increasingly important in funding decisions but most are based on data, which may therefore not represent the general population. We sought to establish the potential of real-world data available within the Clinical Practice Research Datalink (CPRD) and linked Hospital Episode Statistics (HES) to determine comprehensive healthcare utilisation and costs as input variables for economic modelling.

METHODS

A cohort of patients with irritable bowel syndrome (IBS) who first saw a gastroenterologist in 2008 or 2009, and with 3 years of data before and after their appointment, was created in the CPRD. Primary care, outpatient, inpatient, prescription and colonoscopy data were extracted from the linked CPRD and HES. The appropriate cost to the NHS was attached to each event. Total and stratified annual healthcare utilisation rates and costs were calculated before and after the gastroenterology appointment with distribution parameters. Absolute differences were calculated with 95% confidence intervals.

RESULTS

Total annual healthcare costs over 3 years increase by £935 (95% CI £928-941) following a gastroenterology appointment for IBS. We derived utilisation and cost data with parameter distributions stratified by demographics and time. Women, older patients, smokers and patients with greater comorbidity utilised more healthcare resources, which generated higher costs.

CONCLUSIONS

These linked datasets provide comprehensive primary and secondary care data for large numbers of patients, which allows stratification of outcomes. It is possible to derive input parameters appropriate for economic models and their distributions directly from the population of interest.

International publication trends and collaboration performance of China in healthcare science and services research

Background

In recent years, China’s healthcare reforms and related studies have drawn particular global attention. The main objective of this study is to evaluate quantitatively the publication trends and collaboration performance of China in healthcare science and services (HSS) research.

Methods

Scientometric methods and visualization technology were used to survey the growth and development trends of HSS research based on the Web of Science publications during the past 15 years.

Results

China’s international publications on HSS research increased rapidly compared to those of the global HSS and Chinese scientific studies. Growth trends indicate that collaboration among countries, institutions and authors has also increased. China’s leading partners were all developed countries, such as the US, the UK, Australia and Canada, which have contributed to the majority of the joint publications. The academic impact of publications involving partners from European and American countries was relatively higher than those involving partners from Asian countries. Prominent institutions were universities that could be primarily classified into two groups, namely, Mainland China on the one hand and Hong Kong universities and foreign universities on the other. The most prominent actors were elite institutions, such as Peking University, Fudan University, Chinese University of Hong Kong, University of Hong Kong. The papers published by the Chinese Ministry of Health had relatively high academic impact, whereas those published by Mainland China universities alone had a lower academic impact compared to foreign cooperation papers. Issues related to the Chinese healthcare reform, priority diseases (e.g., breast cancer, HIV/AIDS, tuberculosis, etc.), health systems performance, quality of life and measurement tools, aging problems and research methods have been the most popular HSS topics in China in recent years.

Conclusions

Despite the extensive achievement of the Chinese HSS reforms and research, gaps and challenges remain to be addressed, including those related to health insurance and the effects of the evaluation of essential medicine systems, human resources training and allocation in the health sector, government hospitals reforms and health services systems remodeling. These findings could help scholars and decision-makers understand the current status and likely future trends of the Chinese HSS research, and help them select the most appropriate collaboration partners and policies.

Risk of Post-Discharge Venous Thromboembolism and Associated Mortality in General Surgery: A Population-Based Cohort Study Using Linked Hospital and Primary Care Data in England

BACKGROUND

Trends towards day case surgery and enhanced recovery mean that postoperative venous thromboembolism (VTE) may increasingly arise after hospital discharge. However, hospital data alone are unable to capture adverse events that occur outside of the hospital setting. The National Institute for Health and Care Excellence has suggested the use of primary care data to quantify hospital care-related VTE. Data in surgical patients using these resources is lacking. The aim of this study was to measure VTE risk and associated mortality in general surgery using linked primary care and hospital databases, to improve our understanding of harm from VTE that arises beyond hospital stay.

METHODS

This was a longitudinal cohort study using nationally linked primary care (Clinical Practice Research Datalink, CPRD), hospital administrative (Hospital Episodes Statistics, HES), population statistics (Office of National Statistics, ONS) and National Cancer Intelligence Network databases. Routinely collected information was used to quantify 90-day in-hospital VTE, 90-day post-discharge VTE and 90-day mortality in adults undergoing one of twelve general surgical procedures between 1st April 1997 and 31st March 2012. The earliest postoperative recording of deep vein thrombosis or pulmonary embolism in CPRD, HES and ONS was counted in each patient. Covariates from multiple datasets were combined to derive detailed prediction models for VTE and mortality. Limitation included the capture of VTE presenting to healthcare only and the lack of information on adherence to pharmacological thromboprophylaxis as there was no data linkage to hospital pharmacy records.

RESULTS

There were 981 VTE events captured within 90 days of surgery in 168005 procedures (23.7/1000 patient-years). Overall, primary care data increased the detection of postoperative VTE by a factor of 1.38 (981/710) when compared with using HES and ONS only. Total VTE rates ranged between 3.2/1000 patient-years in haemorrhoidectomy to 118.3/1000 patient-years in esophagogastric resection. Predictors of VTE included emergency surgery (OR = 1.91 95%CI 1.60-2.28, p<0.001), age (OR = 1.02 95%CI 1.02-1.03, p<0.001), body mass index (OR = 1.03 95%CI 1.01-1.04, p<0.001), previous VTE (OR = 8.07 95%CI 6.61-9.83, p<0.001), length of stay (OR = 1.00 95%CI 1.00-1.00, p = 0.007) and cancer stages II (OR = 1.38 95%CI 1.03-1.87, p = 0.033), III (OR = 1.50 95%CI 1.11-2.01, p = 0.008) and IV (OR = 1.63 95%CI 1.03-2.59, p = 0.038). Major organ resections had the greatest odds of VTE when adjusted for other risk factors including length of hospital stay. Post-discharge VTE accounted for 64.8% (636/981) of all recorded VTE. In-hospital VTE (165.4/1000 patient-years) was recorded more frequently than post-discharge VTE (16.2/1000 patient-years). Both in-hospital (OR = 2.07 95%CI 1.51-2.85, p<0.001) and post-discharge (OR = 4.03 95%CI 2.95-5.51, p<0.001) VTE independently predicted 90-day mortality. In patients who died and VTE was recorded on HES or CPRD (n = 56), VTE was one of the causes of death in 37.5% (21/56) of cases.

CONCLUSIONS

A large proportion of postoperative VTE was detected in primary care. Evaluation of linked databases was a useful way of measuring postoperative VTE at population level. These resources identified a significant association between post-discharge VTE and mortality in general surgery.

The Australian Pharmaceutical Benefits Scheme data collection: a practical guide for researchers

Background

The Pharmaceutical Benefits Scheme (PBS) is Australia’s national drug subsidy program. This paper provides a practical guide to researchers using PBS data to examine prescribed medicine use.

Findings

Excerpts of the PBS data collection are available in a variety of formats. We describe the core components of four publicly available extracts (the Australian Statistics on Medicines, PBS statistics online, section 85 extract, under co-payment extract). We also detail common analytical challenges and key issues regarding the interpretation of utilisation using the PBS collection and its various extracts.

Conclusions

Research using routinely collected data is increasing internationally. PBS data are a valuable resource for Australian pharmacoepidemiological and pharmaceutical policy research. A detailed knowledge of the PBS, the nuances of data capture, and the extracts available for research purposes are necessary to ensure robust methodology, interpretation, and translation of study findings into policy and practice.

Data Resource Profile: Clinical Practice Research Datalink (CPRD)

The Clinical Practice Research Datalink (CPRD) is an ongoing primary care database of anonymised medical records from general practitioners, with coverage of over 11.3 million patients from 674 practices in the UK. With 4.4 million active (alive, currently registered) patients meeting quality criteria, approximately 6.9% of the UK population are included and patients are broadly representative of the UK general population in terms of age, sex and ethnicity. General practitioners are the gatekeepers of primary care and specialist referrals in the UK. The CPRD primary care database is therefore a rich source of health data for research, including data on demographics, symptoms, tests, diagnoses, therapies, health-related behaviours and referrals to secondary care. For over half of patients, linkage with datasets from secondary care, disease-specific cohorts and mortality records enhance the range of data available for research. The CPRD is very widely used internationally for epidemiological research and has been used to produce over 1000 research studies, published in peer-reviewed journals across a broad range of health outcomes. However, researchers must be aware of the complexity of routinely collected electronic health records, including ways to manage variable completeness, misclassification and development of disease definitions for research.

Risk of erectile dysfunction in transfusion-naive thalassemia men: a nationwide population-based retrospective cohort study

Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction. This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities.

Impact of timing and duration of thiopurine treatment on first perianal surgery in Crohn's disease: UK population-based study (1995-2009)

BACKGROUND

The impact of thiopurine (TP) use on perianal surgery is uncertain. Our aim was to determine trends in perianal surgery and the impact of timing and duration of TPs on the risk of first perianal surgery.

METHODS

We identified a population-based cohort of incident cases of Crohn's disease between 1995 and 2009. We used Kaplan-Meier analysis to determine trends in TP usage and first perianal surgery by era of diagnosis: era 1 (1995-2002) and era 2 (2003-2009). We quantified the impact of duration and timing of TPs on the risk of perianal surgery using a Cox regression model.

RESULTS

We identified a cohort of 5235 incident cases of Crohn's disease. The 5-year cumulative probability of first perianal surgery decreased from 2.7% to 1.7% between era 1 and era 2, respectively (P = 0.03). TP use for greater than 18 months was associated with a 40% risk reduction for first perianal surgery (hazard ratio: 0.60, 95% confidence interval: 0.39-0.95) and 49% if TPs were used for 2 years or more (hazard ratio: 0.51, 95% confidence interval: 0.32-0.99). There was no demonstrable additional benefit from early TP use within the first year after diagnosis (hazard ratio: 0.85, 95% confidence interval: 0.52-1.40, P = 0.53).

CONCLUSIONS

Over the past 15 years, TP use has increased by 50%, whereas perianal surgery rates have decreased by 37% among UK population with Crohn's disease. Sustained use for 18 months was associated with a reduced risk of perianal surgery by almost a half in the first 5 years after diagnosis.

Patient and public attitudes towards informed consent models and levels of awareness of Electronic Health Records in the UK

BACKGROUND

The development of Electronic Health Records (EHRs) forms an integral part of the information strategy for the National Health Service (NHS) in the UK, with the aim of facilitating health information exchange for patient care and secondary use, including research and healthcare planning. Implementing EHR systems requires an understanding of patient expectations for consent mechanisms and consideration of public awareness towards information sharing as might be made possible through integrated EHRs across primary and secondary health providers.

OBJECTIVES

To explore levels of public awareness about EHRs and to examine attitudes towards different consent models with respect to sharing identifiable and de-identified records for healthcare provision, research and planning.

METHODS

A cross-sectional questionnaire survey was administered to adult patients and members of the public in primary and secondary care clinics in West London, UK in 2011. In total, 5331 individuals participated in the survey, and 3157 were included in the final analysis.

RESULTS

The majority (91%) of respondents expected to be explicitly asked for consent for their identifiable records to be accessed for health provision, research or planning. Half the respondents (49%) did not expect to be asked for consent before their de-identified records were accessed. Compared with White British respondents, those from all other ethnic groups were more likely to anticipate their permission would be obtained before their de-identified records were used. Of the study population, 59% reported already being aware of EHRs before the survey. Older respondents and individuals with complex patterns of interaction with healthcare services were more likely to report prior awareness of EHRs. Individuals self-identifying as belonging to ethnic groups other than White British, and those with lower educational qualifications were less likely to report being aware of EHRs than White British respondents and respondents with degree-level education, respectively. Those who reported being aware of EHRs were less likely to say they expected explicit consent to be sought before use of their de-identified record.

CONCLUSIONS

A large number of patients remain unaware of EHRs, while preference for implicit consent is stronger among those who report previous awareness. Differences in awareness levels and consent expectations between groups with different socio-demographic characteristics suggest that public education and information campaigns should target specific groups to increase public awareness and ensure meaningful informed consent mechanisms.

Healthcare resource implications of hypoglycemia-related hospital admissions and inpatient hypoglycemia: retrospective record-linked cohort studies in England

OBJECTIVE

Using a retrospective cohort study, the mean length of hospital stay (LoS) and total per-patient expenditure for hypoglycemia requiring admission to hospital were estimated. In a separate matched retrospective cohort study, the effect of inpatient hypoglycemia on LoS, expenditure, and risk of all-cause mortality while admitted was investigated.

METHODS

The cohorts consisted of patients aged ≥18 years with a diagnosis of type 1 or 2 diabetes between January 1, 2002 and October 30, 2012 in the Clinical Practice Research Datalink database, who had initiated insulin treatment and had a recording of hypoglycemia in the same period. In the matched retrospective cohort study, exposed patients (who experienced hypoglycemia in hospital) were case-matched with patients who did not experience hypoglycemia during admission (unexposed). Generalized linear regression was used to estimate LoS. Risk of all-cause mortality was evaluated via logistic regression.

RESULTS

In the retrospective cohort study (1131 patients), mean LoS was 5.46 (95% CI 4.62 to 6.45) days for type 1 diabetes, and 5.04 (95% CI 4.46 to 5.71) days for type 2 diabetes. Mean cost per admission was £1034 (95% CI £855 to £1253). In the matched retrospective cohort study (1079 pairs of patients), exposed patients had a mean LoS of 11.91 days (95% CI 10.96 to 12.94 days) versus 4.80 (95% CI 4.41 to 5.23) for unexposed patients, p<0.0001. Exposed patients had a higher mortality risk compared with unexposed patients (OR 1.439 (95% CI 1.060to 1.952), p=0.0195). Total average per-patient cost for exposed patients was GBP (£)2235, 40% (p<0.0001) higher than total average admission cost in unexposed patients.

CONCLUSIONS

Hypoglycemia has a significant negative impact on patient outcomes, healthcare resource use, and expenditure.

The impact of timing and duration of thiopurine treatment on colectomy in ulcerative colitis: a national population-based study of incident cases between 1989-2009

BACKGROUND

The role of thiopurines in altering the risk of colectomy in ulcerative colitis (UC) remains unclear.

AIMS

To examine predictors of colectomy in UC and determine the impact of thiopurines on the risk of colectomy.

METHODS

We constructed a population-based cohort of incident cases of UC in the United Kingdom between 1989 and 2009. We determined trends in thiopurine usage and colectomy for three defined cohorts: era 1 (1989-1995), era 2 (1996-2002), era 3 (2003-2009). We used Cox regression to determine predictors of colectomy and quantified the impact of duration and timing of thiopurine use on the risk of colectomy.

RESULTS

We identified 8673 incident cases of UC. 5-year colectomy rates increased from 4.2%, 5.1% to 6.9% (P = 0.001) for era 1, era 2 and era 3, respectively, despite increasing thiopurine use. This was not significant after adjustment for predictors of colectomy (P = 0.06). There was a higher risk of colectomy in men (HR 1.44, 95% CI: 1.19-1.73), those diagnosed at an early age (HR 1.35, 95% CI: 1.04-1.75; 16-24 vs. 25-64) and early steroid users (HR 1.94, 95% CI: 1.59-2.37). 5-ASA users were less likely to require a colectomy (HR 0.35, 95% CI: 0.28-0.44). Amongst thiopurine users, those treated for greater than 12 months had a 71% reduction in risk of colectomy (HR 0.29, 95% CI: 0.21-0.40). Early thiopurines offered no additional benefit.

CONCLUSIONS

Thiopurine exposure for greater than 12 months reduces the likelihood of colectomy by 71%. Young men and those requiring steroids within 3 months of diagnosis are at greatest risk of colectomy, and most likely to benefit from sustained thiopurine use.

The impact of timing and duration of thiopurine treatment on first intestinal resection in Crohn's disease: national UK population-based study 1989-2010

OBJECTIVES

The efficacy of thiopurines (TPs) in altering the risk of surgery in Crohn's disease (CD) remains controversial. We evaluated the impact of TP therapy, optimal timing, and duration of TP therapy on first intestinal resection rates using a population-based cohort.

METHODS

We constructed a population-based cohort of incident cases of CD between 1989 and 2005. We used the Kaplan-Meier analysis to calculate time trends in TP use and first intestinal resection in three groups defined by time period of diagnosis: 1989-1993, 1994-1999, and 2000-2005 groups A, B, and C, respectively. We quantified impact of duration and timing of TP treatment on likelihood of surgery using Cox regression and propensity score matching.

RESULTS

We identified 5,640 eligible patients with CD. The 5-year cumulative probability of TP use increased from 12, 18, to 25% ( P<0.0001) while probability of first intestinal resection decreased from 15, 12 to 9% (P<0.001) in groups A, B, and C, respectively. Patients treated with at least 6 months of TP therapy had a 44% reduction in the risk of surgery (hazards ratio (HR): 0.56; 95% confidence interval (CI): 0.37-0.85) and those receiving at least 12 months of TP therapy had a 69% reduction in the risk of surgery (HR: 0.31; 95% CI: 0.22-0.44). Early treatment (<12 months from diagnosis) vs. late treatment with TP showed no additional benefit in reducing risk of surgery (HR: 0.41; 95% CI: 0.27-0.61 vs. 0.21; 95% CI: 0.13-0.34).

CONCLUSIONS

Over the past 20 years, TP use has doubled, whereas intestinal surgery has fallen by one-third among the UK population of Crohn's patients. Prolonged exposure is associated with a reduced likelihood of surgery whereby more than 12 months TP therapy reduces the risk of first intestinal surgery two-fold; however, early initiation of TP treatment offered no apparent additional benefit.

Study of risk factors for gastric cancer by populational databases analysis

AIM: To study the association between the incidence of gastric cancer and populational exposure to risk/protective factors through an analysis of international databases.

METHODS: Open-access global databases concerning the incidence of gastric cancer and its risk/protective factors were identified through an extensive search on the Web. As its distribution was neither normal nor symmetric, the cancer incidence of each country was categorized according to ranges of percentile distribution. The association of each risk/protective factor with exposure was measured between the extreme ranges of the incidence of gastric cancer (under the 25^th percentile and above the 75^th percentile) by the use of the Mann-Whitney test, considering a significance level of 0.05.

RESULTS: A variable amount of data omission was observed among all of the factors under study. A weak or nonexistent correlation between the incidence of gastric cancer and the study variables was shown by a visual analysis of scatterplot dispersion. In contrast, an analysis of categorized incidence revealed that the countries with the highest human development index (HDI) values had the highest rates of obesity in males and the highest consumption of alcohol, tobacco, fruits, vegetables and meat, which were associated with higher incidences of gastric cancer. There was no significant difference for the risk factors of obesity in females and fish consumption.

CONCLUSION: Higher HDI values, coupled with a higher prevalence of male obesity and a higher per capita consumption of alcohol, tobacco, fruits, vegetables and meat, are associated with a higher incidence of gastric cancer based on an analysis of populational global data.

Frequency of metabolic syndrome and 25-hydroxyvitamin D3 levels in patients with non-alcoholic fatty liver disease

AIM

It is known that insulin resistance has an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and that serum 25-hidroksivitamin D3 [25-(OH)D] levels are found low in the presence of insulin resistance. Metabolic syndrome (MetS) is characterized by insulin resistance. The purpose of the present study was to determine the levels of 25-(OH)D and the frequency of MetS in patients with NAFLD, and to evaluate the association of 25-(OH)D with the histology of NAFLD and metabolic parameters.

METHOD

Sixty-three patients with NAFLD confirmed by liver biopsy (29 females and 34 males, mean age 42.70±9.82 years) and 46 healthy controls (16 females and 30 males, mean age 37.54±8.56 years) were included in the study. International Diabetes Federation criteria were used for MetS diagnosis. Insulin resistance was determined according to the Homeostasis Model of Assessment (HOMA-IR) method. The groups were compared for 25-(OH)D levels and MetS frequencies. Correlation analysis was used to evaluate relationships between 25-(OH)D and metabolic parameters and/or NAFLD histology.

RESULTS

25-(OH)D levels were lower in the NAFLD group compared to the control group (36.06±13.07 ng/mL vs. 51.19±23.45 ng/mL, respectively, P<0.01), while MetS frequency was higher (66.7% vs. 15.2%, P<0.01). In the NAFLD group, 25-(OH)D levels were negatively correlated with non-alcoholic steatohepatitis scores and HOMA-IR (r=-0.317, P=0.011 and r=-0.437, P=0.001, respectively).

CONCLUSION

The present study demonstrated higher frequency of MetS and lower levels of 25-(OH)D in patients with NAFDL, and a negative association of 25-(OH)D levels with non-alcoholic steatohepatitis scores and insulin resistance.

Managing personal health information in distributed research network environments

BACKGROUND

Studying rare outcomes, new interventions and diverse populations often requires collaborations across multiple health research partners. However, transferring healthcare research data from one institution to another can increase the risk of data privacy and security breaches.

METHODS

A working group of multi-site research programmers evaluated the need for tools to support data security and data privacy. The group determined that data privacy support tools should: 1) allow for a range of allowable Protected Health Information (PHI); 2) clearly identify what type of data should be protected under the Health Insurance Portability and Accountability Act (HIPAA); and 3) help analysts identify which protected health information data elements are allowable in a given project and how they should be protected during data transfer. Based on these requirements we developed two performance support tools to support data programmers and site analysts in exchanging research data.

RESULTS

The first tool, a workplan template, guides the lead programmer through effectively communicating the details of multi-site programming, including how to run the program, what output the program will create, and whether the output is expected to contain protected health information. The second performance support tool is a checklist that site analysts can use to ensure that multi-site program output conforms to expectations and does not contain protected health information beyond what is allowed under the multi-site research agreements.

CONCLUSIONS

Together the two tools create a formal multi-site programming workflow designed to reduce the chance of accidental PHI disclosure.

Cancer diagnosed by emergency admission in England: an observational study using the general practice research database

Background

Patients diagnosed with cancer by the emergency route often have more advanced diseases and poorer outcomes. Rates of cancer diagnosed through unplanned admissions vary within and between countries, suggesting potential inconsistencies in the quality of care. To reduce diagnoses by this route and improve patient outcomes, high risk patient groups must be identified. This cross-sectional observational study determined the incidence of first-ever diagnoses of cancer by emergency (unplanned) admission and identified patient-level risk factors for these diagnoses in England.

Methods

Data for 74,763 randomly selected patients at 457 general practices between 1999 and 2008 were obtained from the General Practice Research Database (GPRD), including integrated Hospital Episode Statistics (HES) data and Office for National Statistics (ONS) mortality data. The proportion of first-ever diagnoses by emergency admission out of all recorded first cancer diagnoses by any route was analysed by patient characteristics.

Results

Diagnosis by emergency admission was recorded in 13.9% of patients diagnosed with cancer for the first time (n = 817/5870). The incidence of first cases by the emergency route was 2.51 patients per 10,000 person years. In adjusted regression analyses, patients of older age (p < 0.0001), living in the most deprived areas (RR 1.93, 95% CI 1.51 to 2.47; p < 0.0001) or who had a total Charlson score of 1 compared to 0 (RR 1.34, 95% CI 1.06 to 1.69; p = 0.014) were most at risk of diagnosis by emergency admission. Patients with more prior (all-cause) emergency admissions were less at risk of subsequent diagnosis by the emergency route (RR 0.31 per prior emergency admission, 95% CI 0.20 to 0.46; p < 0.0001).

Conclusions

A much lower incidence of first-ever cancer diagnoses by emergency admission was found compared with previous studies. Identified high risk groups may benefit from interventions to reduce delayed diagnosis. Further studies should include screening and cancer staging data to improve understanding of delayed or untimely diagnosis and patient care pathways.

The Diabetes Pearl: Diabetes biobanking in The Netherlands

Background

Type 2 diabetes is associated with considerable comorbidity and severe complications, which reduce quality of life of the patients and require high levels of healthcare. The Diabetes Pearl is a large cohort of patients diagnosed with type 2 diabetes, covering different geographical areas in the Netherlands. The aim of the study is to create a research infrastructure that will allow the study of risk factors, including biomarkers and genetic determinants for severe diabetes complications.

Methods/design

Baseline examinations began November 2009 and will continue through 2012. By the end of 2012, it is expected that 7000 patients with type 2 diabetes will be included in the Diabetes Pearl cohort. To ensure quality of the data collected, standard operation procedures were developed and used in all 8 recruitment centers. From all patients who provide informed consent, the following information is collected: personal information, medication use, physical examination (antropometry, blood pressure, electrocardiography (ECG), retina photographs, ankle-brachial index, peripheral vibration perception), self-report questionnaire (socio-economic status, lifestyle, (family) history of disease, and psychosocial well-being), laboratory measurements (glucose, A1c, lipid profile, kidney function), biobank material (storage of urine and blood samples and isolated DNA). All gathered clinical data and biobank information is uploaded to a database for storage on a national level. Biobanks are maintained locally at all recruitment centers.

Discussion

The Diabetes Pearl is large-scale cohort of type 2 diabetes patients in the Netherlands aiming to study risk factors, including biomarkers and genetic markers, for disease deterioration and the development of severe diabetes complications. As a result of the well-designed research design and the national coverage, the Diabetes Pearl data can be of great value to national and international researchers with an interest in diabetes related research.

The future of medical diagnostics: large digitized databases

The electronic health record mandate within the American Recovery and Reinvestment Act of 2009 will have a far-reaching affect on medicine. In this article, we provide an in-depth analysis of how this mandate is expected to stimulate the production of large-scale, digitized databases of patient information. There is evidence to suggest that millions of patients and the National Institutes of Health will fully support the mining of such databases to better understand the process of diagnosing patients. This data mining likely will reaffirm and quantify known risk factors for many diagnoses. This quantification may be leveraged to further develop computer-aided diagnostic tools that weigh risk factors and provide decision support for health care providers. We expect that creation of these databases will stimulate the development of computer-aided diagnostic support tools that will become an integral part of modern medicine.

Association of systolic and diastolic blood pressure and all cause mortality in people with newly diagnosed type 2 diabetes: retrospective cohort study

OBJECTIVE

To examine the effect of systolic and diastolic blood pressure achieved in the first year of treatment on all cause mortality in patients newly diagnosed with type 2 diabetes, with and without established cardiovascular disease.

DESIGN

Retrospective cohort study.

SETTING

United Kingdom General Practice Research Database, between 1990 and 2005.

PARTICIPANTS

126,092 adult patients (age ≥ 18 years) with a new diagnosis of type 2 diabetes who had been registered with participating practices for at least 12 months.

MAIN OUTCOME MEASURE

All cause mortality.

RESULTS

Before diagnosis, 12,379 (9.8%) patients had established cardiovascular disease (myocardial infarction or stroke). During a median follow-up of 3.5 years, we recorded 25,495 (20.2%) deaths. In people with cardiovascular disease, tight control of systolic (<130 mm Hg) and diastolic (<80 mm Hg) blood pressure was not associated with improved survival, after adjustment for baseline characteristics (age at diagnosis, sex, practice level clustering, deprivation score, body mass index, smoking, HbA(1c) and cholesterol levels, and blood pressure). Low blood pressure was also associated with an increased risk of all cause mortality. Compared with patients who received usual control of systolic blood pressure (130-139 mm Hg), the hazard ratio of all cause mortality was 2.79 (95% confidence interval 1.74 to 4.48, P<0.001) for systolic blood pressure at 110 mm Hg. Compared with patients who received usual control of diastolic blood pressure (80-84 mm Hg), the hazard ratios were 1.32 (1.02 to 1.78, P=0.04) and 1.89 (1.40 to 2.56, P<0.001) for diastolic blood pressures at 70-74 mm Hg and lower than 70 mm Hg, respectively. Similar associations were found in people without cardiovascular disease. Subgroup analyses of people diagnosed with hypertension and who received treatment for hypertension confirmed initial findings.

CONCLUSION

Blood pressure below 130/80 mm Hg was not associated with reduced risk of all cause mortality in patients with newly diagnosed diabetes, with or without known cardiovascular disease. Low blood pressure, particularly below 110/75 mm Hg, was associated with an increased risk for poor outcomes.