Methods and rationale of the DISCOVER CKD global observational study.

BACKGROUND: Real-world data for patients with chronic kidney disease (CKD), specifically pertaining to clinical management, metabolic control, treatment patterns, quality of life (QoL) and dietary patterns, are limited. Understanding these gaps using real-world, routine care data will improve our understanding of the challenges and consequences faced by patients with CKD, and will facilitate the long-term goal of improving their management and prognosis. METHODS: DISCOVER CKD follows an enriched hybrid study design, with both retrospective and prospective patient cohorts, integrating primary and secondary data from patients with CKD from China, Italy, Japan, Sweden, the UK and the USA. Data will be prospectively captured over a 3-year period from >1000 patients with CKD who will be followed up for at least 1 year via electronic case report form entry during routine clinical visits and also via a mobile/tablet-based application, enabling the capture of patient-reported outcomes (PROs). In-depth interviews will be conducted in a subset of ∼100 patients. Separately, secondary data will be retrospectively captured from >2 000 000 patients with CKD, extracted from existing datasets and registries. RESULTS: The DISCOVER CKD program captures and will report on patient demographics, biomarker and laboratory measurements, medical histories, clinical outcomes, healthcare resource utilization, medications, dietary patterns, physical activity and PROs (including QoL and qualitative interviews). CONCLUSIONS: The DISCOVER CKD program will provide contemporary real-world insight to inform clinical practice and improve our understanding of the epidemiology and clinical and economic burden of CKD, as well as determinants of clinical outcomes and PROs from a range of geographical regions in a real-world CKD setting.

Incidence of Uncommon Clinical Events in USA Patients with Dialysis-Dependent and Nondialysis-Dependent Chronic Kidney Disease: Analysis of Electronic Health Records from TriNetX.

INTRODUCTION: Further understanding of adverse clinical events in patients with chronic kidney disease (CKD) is needed. This study aimed to describe characteristics of patients with nondialysis-dependent (NDD) and dialysis-dependent (DD) CKD and to assess incidence rates of uncommon adverse clinical events of interest in these patients. METHODS: This retrospective study used electronic medical record data from USA CKD patients (≥18 years) with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 between January 1, 2010, and December 31, 2018, obtained from the USA-based TriNetX database. NDD-CKD and DD-CKD were diagnosed and staged from ≥2 consecutive eGFR readings, recorded ≥90 days apart. Dialysis was identified using procedure codes for renal replacement therapy. Outcomes assessed were select uncommon adverse clinical events, defined by International Classification of Disease, 9th and 10th Revision codes. RESULTS: Incidence rates of adverse clinical events per 100 person-years (95% confidence interval) were generally higher in patients with DD-CKD versus NDD-CKD. Differences were particularly pronounced for hyperkalemia (26.9 [26.2-27.6] vs. 4.5 [4.5-4.6]), acidosis (15.1 [14.7-15.6] vs. 3.4 [3.4-3.4]), and sepsis (14.6 [14.2-15.1] vs. 3.3 [3.3-3.4]). Among DD-CKD patients, incidence rates of adverse events were particularly high during the first 3 months following dialysis initiation. Incidence of adverse clinical events generally increased with decreasing eGFR among patients with NDD-CKD and with hemoglobin <10 g/dL in both NDD- and DD-CKD patients. CONCLUSIONS: Our results help establish baseline rates of uncommon adverse clinical events and provide additional evidence of increased morbidity for patients with DD-CKD versus NDD-CKD.

Antibiotic use and the risk of rheumatoid arthritis: a population-based case-control study.

BACKGROUND: Antibiotic-induced disturbances of the human microbiota have been implicated in the development of chronic autoimmune conditions. This study aimed to assess whether antibiotic use is associated with the onset of rheumatoid arthritis (RA). METHODS: A nested case-control study was conducted utilising data from the primary care Clinical Practice Research Datalink (CPRD). Patients with an incident diagnosis of RA were identified (1995-2017). Each case was matched on age, gender, and general practice to ≥ 5 controls without RA. Conditional logistic regression was used to examine previous antibiotic prescriptions and RA onset after controlling for confounding factors. RESULTS: We identified 22,677 cases of RA, matched to 90,013 controls, with a median follow-up of 10 years before RA diagnosis. The odds of developing RA were 60% higher in those exposed to antibiotics than in those not exposed (OR 1.60; 95% CI 1.51-1.68). A dose- or frequency-dependent association was observed between the number of previous antibiotic prescriptions and RA. All classes of antibiotics were associated with higher odds of RA, with bactericidal antibiotics carrying higher risk than bacteriostatic (45% vs. 31%). Those with antibiotic-treated upper respiratory tract (URT) infections were more likely to be RA cases. However, this was not observed for URT infections not treated with antibiotics. Antifungal (OR = 1.27; 95% CI 1.20-1.35) and antiviral (OR = 1.19; 95% CI 1.14-1.24) prescriptions were also associated with increased odds of RA. CONCLUSION: Antibiotic prescriptions are associated with a higher risk of RA. This may be due to microbiota disturbances or underlying infections driving risk. Further research is needed to explore these mechanisms.

Venous thromboembolism in patients with gout and the impact of hospital admission, disease duration and urate-lowering therapy.

BACKGROUND: Systemic inflammatory diseases have been associated with increased risk of venous thromboembolism. We aimed to quantify the risk of venous thromboembolism in patients with gout, the most common inflammatory arthritis, and to assess how disease duration, hospital admission and urate-lowering therapy affect this risk. METHODS: We used data from the population-representative, England-based Clinical Practice Research Datalink linked to Hospital Episode Statistics, to identify incident gout cases between 1998 and 2017. We matched cases individually to 1 control without gout on age, gender, general practice and follow-up time. We calculated absolute and relative risks of venous thromboembolism, stratified by age, gender and hospital admission. Among those with gout, we assessed the risk of venous thromboembolism by exposure to urate-lowering therapy. RESULTS: We identified 62 234 patients with incident gout matched to 62 234 controls. Gout was associated with higher risk of venous thromboembolism compared with controls (absolute rate 37.3 [95% confidence interval (CI) 35.5-39.3] v. 27.0 [95% CI 25.5-28.9] per 10 000 person-years, adjusted hazard ratio [HR] 1.25, 95% CI 1.15-1.35). The excess risk in patients with gout, which was sustained up to a decade after diagnosis, was present during the time outside hospital stay (adjusted HR 1.30, 95% CI 1.18-1.42), but not during it (adjusted HR 1.01, 95% CI 0.83-1.24). The risk of venous thromboembolism was similar among patients prescribed versus not prescribed urate-lowering therapy (incidence rate ratio 1.04, 95% CI 0.89-1.23). INTERPRETATION: Gout was associated with higher risk of venous thromboembolism, particularly when the patient was not in hospital and regardless of exposure to urate-lowering therapy. Although the observed excess risk may not be sufficient to warrant preventive intervention, clinical vigilance may be required when caring for these patients.

Glycaemic, gastrointestinal and appetite responses to breakfast porridges from ancient cereal grains: A MRI pilot study in healthy humans.

Cereal grain based porridges are commonly consumed throughout the world. Whilst some data are available for varieties that are popular in the Western world such as oats and rye, other 'ancient' grains used in the East and in Africa such as millets are thought to have beneficial health effects, such as a suppression of post prandial hunger and circulating glucose levels. These grains, a sustainable food source due to their tolerance of extreme weather and growing conditions, are commonly found throughout Asia and Africa. However, knowledge of the physiological responses to these grain varieties is very limited. This study aimed to collect initial pilot data on the physiological and gastrointestinal responses to breakfast porridges made with two millet varieties and oats and rye grains. A total of n=15 completed the oats and rye, n=9 the finger millet n=12 the pearl millet meals. MRI scans were undertaken at baseline, immediately after consumption and then hourly postprandially. Blood glucose was measured at baseline, immediately after consumption and then every 15min until t=80min, then every 20min until t=120min, followed on each occasion by completion of VAS. Seven participants completed the entire protocol and were included in the final analysis. A subgroup analysis with the n=10 paired comparison between the same individuals that completed the oats, rye and pearl millet was also considered. The gastric volume AUC was higher for pearl millet than oats and rye (n=10, p<0.001). The incremental area under the curve (iAUC) for blood glucose was not significantly different between the meals although this showed a trend to be lower for pearl millet. Hunger was lower for pearl millet compared to oats and rye (n=10, p=0.01). There was a significant correlation between total gastric volume AUC and average appetite AUC r=-0.47, p<0.010. Isoenergetic breakfast porridges from 'ancient' varieties of millet grains showed physiological responses that were comparable with those from common Western varieties known to have beneficial health effects. Pearl millet appeared to induce lower postprandial blood glucose response and appetite scores though the differences were not conclusive compared with the other porridges and further work is needed. Improved knowledge of the effects of different cereal grains could help direct dietary advice and ultimately improve health outcomes in the general population worldwide.

Risk of chronic kidney disease in patients with gout and the impact of urate lowering therapy: a population-based cohort study.

BACKGROUND: An association between gout and renal disease is well-recognised but few studies have examined whether gout is a risk factor for subsequent chronic kidney disease (CKD). Additionally, the impact of urate-lowering therapy (ULT) on development of CKD in gout is unclear. The objective of this study was to quantify the risk of CKD stage ≥ 3 in people with gout and the impact of ULT. METHODS: This was a retrospective cohort study using data from the Clinical Practice Research Datalink (CPRD). Patients with incident gout were identified from general practice medical records between 1998 and 2016 and randomly matched 1:1 to patients without a diagnosis of gout based on age, gender, available follow-up time and practice. Primary outcome was development of CKD stage ≥ 3 based on estimated glomerular filtration rate (eGFR) or recorded diagnosis. Absolute rates (ARs) and adjusted hazard ratios (HRs) were calculated using Cox regression models. Risk of developing CKD was assessed among those prescribed ULT within 1 and 3 years of gout diagnosis. RESULTS: Patients with incident gout (n = 41,446) were matched to patients without gout. Development of CKD stage ≥ 3 was greater in the exposed group than in the unexposed group (AR 28.6 versus 15.8 per 10,000 person-years). Gout was associated with an increased risk of incident CKD (adjusted HR 1.78 95% CI 1.70 to 1.85). Those exposed to ULT had a greater risk of incident CKD, but following adjustment this was attenuated to non-significance in all analyses (except on 3-year analysis of women (adjusted HR 1.31 95% CI 1.09 to 1.59)). CONCLUSIONS: This study has demonstrated gout to be a risk factor for incident CKD stage ≥ 3. Further research examining the mechanisms by which gout may increase risk of CKD and whether optimal use of ULT can reduce the risk or progression of CKD in gout is suggested.

Risk of fragility fracture among patients with gout and the effect of urate-lowering therapy.

BACKGROUND: Previous studies that quantified the risk of fracture among patients with gout and assessed the potential effect of urate-lowering therapy have provided conflicting results. Our study aims to provide better estimates of risk by minimizing the effect of selection bias and confounding on the observed association. METHODS: We used data from the Clinical Practice Research Datalink, which records primary care consultations of patients from across the United Kingdom. We identified patients with incident gout from 1990 to 2004 and followed them up until 2015. Each patient with gout was individually matched to 4 controls on age, sex and general practice. We calculated absolute rate of fracture and hazard ratios (HRs) using Cox regression models. Among patients with gout, we assessed the impact of urate-lowering therapy on fracture, and used landmark analysis and propensity score matching to account for immortal time bias and confounding by indication. RESULTS: We identified 31 781 patients with incident gout matched to 122 961 controls. The absolute rate of fracture was similar in both cases and controls (absolute rate = 53 and 55 per 10 000 person-years, respectively) corresponding to an HR of 0.97 (95% confidence interval 0.92-1.02). Our finding remained unchanged when we stratified our analysis by age and sex. We did not observe statistically significant differences in the risk of fracture among those prescribed urate-lowering therapy within 1 and 3 years after gout diagnosis. INTERPRETATION: Overall, gout was not associated with an increased risk of fracture. Urate-lowering drugs prescribed early during the course of disease had neither adverse nor beneficial effect on the long-term risk of fracture.

Risk of fracture among patients with polymyalgia rheumatica and giant cell arteritis: a population-based study.

BACKGROUND: Glucocorticoids are associated with increased fracture risk and are the mainstay of treatment in polymyalgia rheumatica (PMR) and giant cell arteritis (GCA). However, fracture risk in these conditions has not been previously quantified. The aim of this study was to quantify the risk of fracture among patients with PMR and GCA. METHODS: A retrospective cohort study was conducted using primary care records from the UK-based Clinical Practice Research Datalink. Individuals aged 40 years and over, with incident diagnoses of PMR or GCA were separately identified from 1990-2004 and followed up until 2015. For each exposed individual, four age-, sex- and practice-matched controls were randomly selected. Incidence rates of fracture per 10,000 person-years were calculated for each disease group and hazard rates were compared to the unexposed using Cox regression models. RESULTS: Overall, 12,136 and 2673 cases of PMR and GCA, respectively, were identified. The incidence rate of fracture was 148.05 (95% CI 141.16-155.28) in PMR and 147.15 (132.91-162.91) in GCA per 10,000 person-years. Risk of fracture was increased by 63% in PMR (adjusted hazard ratio 1.63, 95% CI 1.54-1.73) and 67% in GCA (1.67, 1.49-1.88) compared to the control populations. Fewer than 13% of glucocorticoid-treated cases were prescribed bisphosphonates. CONCLUSIONS: This study reports, for the first time, a similar increase in fracture risk for patients with PMR and GCA. More needs to be done to improve adherence to guidelines to co-prescribe bisphosphonates. Further research needs to identify whether lower glucocorticoid starting doses and/or aggressive dose reduction reduces fracture risk.

Development and validation of risk prediction model for venous thromboembolism in postpartum women: multinational cohort study.

OBJECTIVE:  To develop and validate a risk prediction model for venous thromboembolism in the first six weeks after delivery (early postpartum). DESIGN:  Cohort study. SETTING:  Records from England based Clinical Practice Research Datalink (CPRD) linked to Hospital Episode Statistics (HES) and data from Sweden based registry. PARTICIPANTS:  All pregnant women registered with CPRD-HES linked data between 1997 and 2014 and Swedish medical birth registry between 2005 and 2011 with postpartum follow-up. MAIN OUTCOME MEASURE:  Multivariable logistic regression analysis was used to develop a risk prediction model for postpartum venous thromboembolism based on the English data, which was externally validated in the Swedish data. RESULTS:  433 353 deliveries were identified in the English cohort and 662 387 in the Swedish cohort. The absolute rate of venous thromboembolism was 7.2 per 10 000 deliveries in the English cohort and 7.9 per 10 000 in the Swedish cohort. Emergency caesarean delivery, stillbirth, varicose veins, pre-eclampsia/eclampsia, postpartum infection, and comorbidities were the strongest predictors of venous thromboembolism in the final multivariable model. Discrimination of the model was similar in both cohorts, with a C statistic above 0.70, with excellent calibration of observed and predicted risks. The model identified more venous thromboembolism events than the existing national English (sensitivity 68% v 63%) and Swedish guidelines (30% v 21%) at similar thresholds. CONCLUSION:  A new prediction model that quantifies absolute risk of postpartum venous thromboembolism has been developed and externally validated. It is based on clinical variables that are available in many developed countries at the point of delivery and could serve as the basis for real time decisions on obstetric thromboprophylaxis.

Risk of acute appendicitis in and around pregnancy: a population-based cohort study from England.

OBJECTIVE: To determine the absolute and relative risk of acute appendicitis during the antepartum and postpartum periods compared with the time outside pregnancy among women of childbearing age. BACKGROUND: Acute appendicitis is the most common nonobstetric surgical emergency during pregnancy. Estimates of the incidence of acute appendicitis in pregnancy remain imprecise and inconsistent. METHODS: All potential fertile women aged 15 to 44 years registered within Clinical Practice Research Datalink with linkages to the Hospital Episodes Statistics between 1997 and 2012 were identified. Absolute rates of acute appendicitis were calculated during the antepartum and postpartum periods and were compared with the time outside pregnancy in terms of incidence rate ratio (IRR) using a Poisson regression model. RESULTS: Among 1,624,804 women, there were 362,219 pregnancies resulting in live or stillbirths. Compared with the time outside pregnancy, the rate of acute appendicitis was 35% lower during the antepartum period [IRR, 0.65; 95% confidence interval (CI), 0.55-0.76], with the lowest rate reported during the third trimester (IRR, 0.47; 95% CI, 0.35-0.64) for all ages; no increased risk of acute appendicitis was observed in the postpartum period compared with the time outside pregnancy among women aged 15 to 34 years but an 84% increased risk for women older than 35 years (IRR, 1.84; 95% CI, 1.18-2.86). The highest and lowest rates of negative appendectomy were encountered in the second and the third trimesters, respectively. CONCLUSIONS: Pregnant women are less likely to be diagnosed with acute appendicitis than nonpregnant women, with the lowest risk reported during the third trimester.

Women with celiac disease present with fertility problems no more often than women in the general population.

BACKGROUND & AIMS: Studies have associated infertility with celiac disease. However, these included small numbers of women attending infertility specialist services and subsequently screened for celiac disease, and therefore may not have been representative of the general population. We performed a large population-based study of infertility and celiac disease in women from the United Kingdom. METHODS: We identified 2,426,225 women with prospective UK primary care records between 1990 and 2013 during their child-bearing years from The Health Improvement Network database. We estimated age-specific rates of new clinically recorded fertility problems among women with and without diagnosed celiac disease. Rates were stratified by whether celiac disease was diagnosed before the fertility problem or afterward and compared with rates in women without celiac disease using Poisson regression, adjusting for sociodemographics, comorbidities, and calendar time. RESULTS: Age-specific rates of new clinically recorded fertility problems in 6506 women with celiac disease were similar to the rates in women without celiac disease (incidence rate ratio, 1.12; 95% confidence interval, 0.88-1.42 among women age 25-29 years). Rates of infertility among women without celiac disease were similar to those of women with celiac disease before and after diagnosis. However, rates were 41% higher among women diagnosed with celiac disease when they were 25-29 years old, compared with women in the same age group without celiac disease (incidence rate ratio, 1.41; 95% confidence interval, 1.03-1.92). CONCLUSIONS: Women with celiac disease do not have a greater likelihood of clinically recorded fertility problems than women without celiac disease, either before or after diagnosis, except for higher reports of fertility problems between 25-39 years if diagnosed with CD. These findings should assure most women with celiac disease that they do not have an increased risk for fertility problems.

Risk factors for first venous thromboembolism around pregnancy: a population-based cohort study from the United Kingdom.

Knowledge of the absolute risk (AR) for venous thromboembolism (VTE) in women around pregnancy and how potential risk factors modify this risk is crucial in identifying women who would benefit most from thromboprophylaxis. We examined a large primary care database containing 376 154 pregnancies ending in live birth or stillbirth from women aged 15 to 44 years between 1995 and 2009 and assessed the effect of risk factors on the incidence of antepartum and postpartum VTE in terms of ARs and incidence rate ratios (IRR), using Poisson regression. During antepartum, varicose veins, inflammatory bowel disease (IBD), urinary tract infection, and preexisting diabetes were associated with an increased risk for VTE (ARs, ≥139/100 000 person-years; IRRs, ≥1.8/100 000 person-years). Postpartum, the strongest risk factor was stillbirth (AR, 2444/100 000 person-years; IRR, 6.2/100 000 person-years), followed by medical comorbidities (including varicose veins, IBD, or cardiac disease), a body mass index (BMI) of 30 kg/m(2) or higher, obstetric hemorrhage, preterm delivery, and caesarean section (ARs, ≥637/100 000 person-years; IRRs, ≥1.9/100 000 person-years). Our findings suggest that VTE risk varies modestly by recognized factors during antepartum; however, women with stillbirths, preterm births, obstetric hemorrhage, caesarean section delivery, medical comorbidities, or a BMI of 30 kg/m(2) or higher are at much higher risk for VTE after delivery. These risk factors should receive careful consideration when assessing the potential need for thromboprophylaxis during the postpartum period.

Risk of first venous thromboembolism in and around pregnancy: a population-based cohort study.

Knowledge of the absolute and relative risk of venous thromboembolism (VTE) in and around pregnancy would be crucial in identifying when to commence and cease thromboprophylaxis in women who would benefit from such intervention. We addressed this hypothesis using a large prospective primary care database from the United Kingdom, containing details on 972683 women aged 15-44years between 1987 and 2004. Risks of a first VTE during antepartum, postpartum and outside of pregnancy were compared using Poisson regression. The rate of VTE during the third trimester antepartum was six times higher than time outside pregnancy [Incidence Rate Ratio (IRR)=6·1; 95% confidence interval, 4·7-7·9]. In contrast, both the first (IRR=1·6) and second (IRR=2·1) trimesters conferred little increase in risk. The first 6weeks postpartum was associated with a 22-fold increase in risk, with the peak occurring in the first 3weeks. Increased age was found to be associated with VTE during postpartum and outside of pregnancy, but not during antepartum. Our findings of a notably raised risk of VTE persisting for 3 weeks postpartum and of a raised antepartum risk constrained to the third trimester have implications for modifying the current recommendations for VTE prophylaxis in pregnancy and the puerperium.