Population-based Matched Cohort Study Research Articles

Investigating the risk of malignancy in elderly patients with psoriasis: A population-based retrospective matched cohort study

Investigating the risk of malignancy in elderly patients with psoriasis: A population-based retrospective matched cohort study

Outpatients prescribed with fluvoxamine around the time of COVID-19 diagnosis are not at a reduced risk of subsequent hospitalization and death compared to their non-prescribed peers: population-based matched cohort study.

To assess the effect of exposure to fluvoxamine around the COVID-19 diagnosis on subsequent hospitalizations and mortality in COVID-19 outpatients in a real-life setting. Using nationwide administrative data, we identified adult COVID-19 outpatients diagnosed up to August 15, 2021 and conducted two cohort studies. Study 1 included subjects prescribed fluvoxamine around the index COVID-19 diagnosis (Cohort A), their peers suffering similar psychiatric difficulties but not prescribed fluvoxamine (Cohort B) and those free of psychiatric difficulties/treatments (Cohort C). Study 2 included subjects prescribed fluvoxamine (Cohort Fluvoxamine) and their peers prescribed paroxetine (Cohort Paroxetine). Cohorts were mutually exactly matched and incidence of COVID-19-related hospitalization, 30-day all-cause hospitalization and of COVID-19-related mortality was estimated. Of the 416,030 first-episode outpatients, Study 1 included 1016 Cohort A, 95,984 Cohort B and 275,804 Cohort C patients. Matched Cohort A (n = 749) vs. Cohort B (n = 31,336) relative risks (95%CI/CrI), frequentist and Bayes with skeptical, otpimistic and pesimistic priors, were COVID-related hospitalization 1.37 (0.56-3.33), 1.15 (0.55-2.11), 1.03 (0.56.1.96) and 1.43 (0.63-2.94), respectively; 30-day all-cause hospitalization 1.88 (0.76-4.67), 1.76 (1.39-2.25), 1.76 (1.39-2.24) and 1.86 (1.43-2.38), respectively; COVID-19-related mortality 0.73 (0.35-1.55), 0.93 (0.53-1.76), 0.79 (0.40-1.54) and 0.88 (0.37-2.11), respectively. Matched Cohort A vs. C (866 vs. 222,792) comparison yielded similar estimates, as did the matched Cohort Fluvoxamine vs. Paroxetine comparison in Study 2 (344 of 994 matched to 535 of 1796 patients). Outpatients prescribed fluvoxamine around the time of COVID-19 diagnosis were not at a reduced risk of hospitalizations and mortality compared to their non-prescribed peers.

Risk of pancreatic cancer in individuals with celiac disease in the United States: A population-based matched cohort study

Celiac disease (CD) has been associated with gastrointestinal malignancies. However, the magnitude of the risk of pancreatic cancer (PC) associated with CD is much less clear, and risks have not been estimated from large populations. To assess the risk of PC in CD patients. We conducted a population-based, multicenter, propensity score-matched cohort study with consecutive patients diagnosed with CD using the TriNeTx research network platform. We examined the incidence of PC in patients with CD compared with a matched cohort of patients without CD (non-CD, controls). Each patient in the main group (CD) was matched to a patient in the control group using 1:1 propensity score matching to reduce confounding effects. The incidence of PC was estimated using a Cox proportional hazards model with a hazard ratio (HR) and 95% confidence interval (CI). A total of 389980 patients were included in this study. Among them, 155877 patients had a diagnosis of CD, and the remaining 234103 individuals without CD were considered a control cohort. The mean duration of follow-up for patients in the CD and control cohorts was 5.8 ± 1.8 and 5.9 ± 1.1 years, respectively. During the follow-up, 309 patients with CD developed PC, whereas 240 patients developed PC in the control group (HR = 1.29; 95%CI: 1.09-1.53). In the secondary analyses in the first year after diagnosis of CD, patients with CD were at a significant increase in risk for PC; 151 patients with CD had an incidence of PC compared with 96 incidences of PC among the patients in the non-CD control group (HR = 1.56; 95%CI: 1.20-2.01) and sensitivity analysis showed similar magnitude to the one generated in the primary and secondary analysis. Patients with CD are at increased risk of PC. Risk elevation persists beyond the first year after diagnosis to reference individuals without CD from the general population.

Celiac disease and risk of microscopic colitis: A nationwide population-based matched cohort study.

An association has been reported between celiac disease (CD) and microscopic colitis (MC). However, large, population-based cohort studies are rare. To systematically examine the association between CD and MC in a large, nationwide cohort. We conducted a nationwide population-based matched cohort study in Sweden of 45,138 patients with biopsy-verified CD (diagnosed in 1990-2016), 223,149 reference individuals, and 51,449 siblings of CD patients. Data on CD and MC were obtained from all (n=28) pathology departments in Sweden. Adjusted hazard ratios (aHRs) were calculated using Cox regression. During follow-up, 452 CD patients and 197 reference individuals received an MC diagnosis (86.1 vs. 7.5 per 100,000person-years). This difference corresponded to an aHR of 11.6 (95% confidence interval [CI]=9.8-13.8) or eight extra MC cases in 1000 CD patients followed up for 10years. Although the risk of MC was highest during the first year of follow-up (aHR 35.2; 95% CI=20.1-61.6), it remained elevated even after 10years (aHR 8.1; 95% CI=6.0-10.9). Examining MC subtypes lymphocytic colitis (LC) and collagenous colitis (CC) separately, the aHR was 12.4 (95% CI=10.0-15.3) for LC and 10.2 (95% CI=7.7-13.6) for CC. MC was also more common before CD (adjusted odds ratio [aOR]=52.7; 95% CI=31.4-88.4). Compared to siblings, risk estimates decreased but remained elevated (CD and later MC: HR=6.2; CD and earlier MC: aOR=7.9). Our study demonstrated a very strong association of MC with CD with an increased risk of future and previous MC in CD patients. The magnitude of the associations underscores the need to consider the concomitance of these diagnoses in cases in which gastrointestinal symptoms persist or recur despite a gluten-free diet or conventional MC treatment. The comparatively lower risk estimates in sibling comparisons suggest that shared genetic and early environmental factors may contribute to the association between CD and MC.

Morbidity Associated With Primary Hyperparathyroidism-A Population-based Study With a Subanalysis on Vitamin D.

Primary hyperparathyroidism (PHPT) is associated with increased risk of morbidity and death, and vitamin D levels are a potentially confounding variable. The aim of this study was to assess morbidity and mortality associated with primary hyperparathyroidism (PHPT). In this population-based retrospective matched cohort study, data linkage of biochemistry, hospital admissions, prescribing, imaging, pathology, and deaths was used to identify patients across the region of Tayside, Scotland, who had PHPT from 1997 to 2019. Cox proportional hazards models and hazards ratios (HR) were used to explore the relationship between exposure to PHPT and several clinical outcomes. Comparisons were made with an age- and gender-matched cohort. In 11 616 people with PHPT (66.8% female), with a mean follow-up period of 8.8 years, there was an adjusted HR of death of 2.05 (95% CI, 1.97-2.13) for those exposed to PHPT. There was also an increased risk of cardiovascular disease (HR = 1.34; 95% CI, 1.24-1.45), cerebrovascular disease (HR = 1.29; 95% CI, 1.15-1.45), diabetes (HR = 1.39; 95% CI, 1.26-1.54), renal stones (HR = 3.02; 95% CI, 2.19-4.17) and osteoporosis (HR = 1.31; 95% CI, 1.16-1.49). Following adjustment for serum vitamin D concentrations (n = 2748), increased risks for death, diabetes, renal stones, and osteoporosis persisted, but not for cardiovascular or cerebrovascular disease. In a large population-based study, PHPT was associated with death, diabetes, renal stones, and osteoporosis, independent of serum vitamin D concentration.

Increased risk of cardiovascular disease associated with diabetes among adult cancer survivors: a population-based matched cohort study.

Diabetes is a well-established risk factor for cardiovascular disease (CVD), but little is known about the differences in contribution of diabetes to incident CVD between adult cancer survivors and those without history of cancer. The aim of this study was to evaluate the magnitude of association between diabetes and CVD risk among adult cancer survivors and their general population counterparts. The National Health Insurance Service database was used to abstract data on 5199 adult cancer survivors and their general population controls in a 1:1 age- and sex-matched cohort setting. The Cox proportional hazards model adjusted for socioeconomic status, health status, lifestyle, and clinical characteristics was used to calculate hazard ratios (HR) and 95% confidence intervals (95% CI) of incident CVD associated with glycaemic status in adult cancer survivors and the general population. The partial likelihood ratio test was used to compare the magnitude of the association between diabetes and CVD risk in the two groups. Compared to those without diabetes, adult cancer survivors (adjusted HR = 2.30; 95% CI: 1.24-4.30) and their general population controls (adjusted HR = 1.91; 95% CI: 1.02-3.58) with diabetes had a higher risk of incident cardiovascular outcomes. The magnitude of diabetes-CVD association was significantly stronger in adult cancer survivors than that in those without history of cancer (P = 0.011). The magnitude of association between diabetes and incident CVD was stronger in adult cancer survivors as compared to that in their general population counterparts, supporting evidence for the importance of glycaemic control for prevention of CVD among those with history of cancer diagnosis and treatment.

Effect of Epidural Block in the Incidence of Postherpetic Neuralgia: A Population-Based Matched-Cohort Study.

Incidence of postherpetic neuralgia (PHN) increases with age. Epidural block in patients with herpes zoster (HZ) is expected to decrease the risk of PHN. The purpose of this study was to evaluate the effectiveness of epidural block on PHN incidence in a population-based study. This was a retrospective matched cohort study and data were sourced from the Korean National Health Insurance Service. The study cohort comprised 427 patients diagnosed with HZ who received epidural block within 30 days after a diagnosis of HZ. The matched control cohort included 427 patients without epidural block and were randomly matched to the study cohort at a 1:1 ratio based on covariates such as sociodemographic factors. The log-rank test was used to assess differences in the incidence of PHN. Cox proportional hazards regression models were used to estimate the hazard ratio (HR) for subsequent PHN, while controlling for potential comorbidities. Among the 854 sampled patients, 30 (7.03%) from the study cohort and 18 (4.22%) from the match-control developed PHN during follow-up. There were no significant differences in the incidence of PHN between the two cohorts (p=0.08). Cox proportional hazard regressions showed that the HR for PHN in patients with epidural block was 1.66 (95% confidence interval, 0.91-3.02; p=0.10). Our study indicates that epidural block did not effectively prevent PHN. However, further studies are needed to determine the effect of epidural block in patients with HZ for the prevention of PHN.

The epidemiology and healthcare costs of community-acquired pneumonia in Ontario, Canada: a population-based cohort study

ObjectivesThe aim of the present study was to determine incidence-based short- and long-term healthcare costs attributable to community-acquired pneumonia (CAP) from the healthcare payer perspective in Ontario, Canada.MethodsWe conducted a retrospective population-based matched cohort study of residents in Ontario, Canada using health administrative data. We identified subjects with an incident episode of CAP (exposed subjects) between 1 January 2012 and 31 December 2014. The index date of each episode was based on the first inpatient or outpatient claim for pneumonia. Exposed subjects were matched without replacement to unexposed subjects from the general population using hard and propensity score matching on age, sex, income quintile, rural residence, comorbidities, and healthcare costs prior to index date. Attributable costs represented the mean difference in costs between the exposed subjects and their matched pairs.ResultsWe identified 692,090 subjects with at least one episode of CAP between 1 January 2012 and 31 December 2014. Adults aged 65 years and older had the highest annual incidence rate of 50.1 episodes per 1,000 person-years, while adults aged 18–64 years and children (aged 0–17) had incidence rates of 12.9 and 24.7 episodes per 1,000 person-years, respectively. The majority of episodes involved care exclusively in the outpatient setting (92.6%), with most of these episodes involving a single physician visit. The mean attributable costs were $1,595 (95% CI: $1,572–$1,616) per outpatient CAP episode and $12,576 (95% CI: $12.392–$12,761) per inpatient CAP episode. Attributable costs were significantly higher for adult subjects and those with time spent in the intensive care unit. Alternative case definitions yielded different results, although demonstrated the same overall trends across groups.ConclusionCAP is associated with substantially increased acute and long-term healthcare costs compared to unexposed subjects. This study highlights the burden of CAP in both the inpatient and outpatient setting, and will serve to inform strategic healthcare planning for future interventions and healthcare programs.

P851 Impact of an integrated model of care for inflammatory bowel disease on direct healthcare costs: A population-based matched cohort study from Saskatchewan, Canada

Abstract Background Integrated models of care (IMC) for IBD lead to reduced hospitalizations, surgeries, comorbidities, and overall improved outcomes. There are limited studies assessing the impact of IMC on direct healthcare costs. We aimed to estimate the impact of exposure to an IMC on direct healthcare costs among individuals diagnosed with IBD. Methods We conducted a quasi-experimental difference-in-difference (DID) cost analysis using administrative health data from Saskatchewan, Canada. We included individuals ≥18 years old meeting a validated administrative IBD case definition between January 2009 and March 2015. IBD cases were classified as exposed or non-exposed to the Saskatchewan IMC and required to have three years of healthcare coverage after baseline (i.e., first visit with an IMC [exposed] or a non-IMC [non-exposed] gastroenterologist). The direct healthcare costs were derived from the administrative databases, adjusted to 2014/15 Canadian dollars, and categorized into hospitalizations, physician visits, and medication claim costs (i.e., immunomodulators [IMM], biologics [BIOL], aminosalicylates[5-ASA]). Propensity scores (PS) were calculated based on healthcare utilization and comorbidities in the 12 months before baseline. Cases (exposed) were matched 1:5 controls (non-exposed) based on PS and disease duration. DID estimators were determined for each cost category using mixed linear regression models including age, sex, disease type, and area of residence as covariables. Results In total, 2905 IBD cases were included in the study, 597 exposed and 2308 non-exposed individuals (Figure); the majority were females (52%), lived in urban areas (74%), and had Crohn’s Disease (61%). The mean age was 44.6 years (SD=15.5) and the average disease duration at baseline was 5.7 years (SD=5). In comparison to the non-exposed group, the costs of physician visits (IBD-related [DID= $-139, 95%CI -209 to -68], IBD-specific [DID=$-155, 95%CI -212 to -97], and specialty visits [DID=$-135, 95%CI -201 to -69]); and IMM dispensations (DID=$-18, 95%CI -35 to -2) were lower in the exposed group. Conversely, we identified higher total healthcare costs (DID=$1707, 95%CI 369 to 3044); IBD-related medication (DID=$2341, 95%CI 1484 to 3197) and BIOL (DID= $2467, 95%CI 1605 to 3328) dispensations costs in the exposed group. There were no other statistically significant differences between the groups. Conclusion We identified lower physician visit and IMM costs in the exposed group than in the non-exposed one. Total healthcare costs were higher among the exposed group, largely driven by higher BIOL costs. These results highlight the potential cost impact of IMC for IBD and the need for cost-effectiveness studies of IMC to further assess value of this care model.

Clinical characteristics and outcomes of COVID-19 in patients with autoimmune hepatitis: A population-based matched cohort study.

Patients with autoimmune hepatitis (AIH) require life-long immunosuppressive agents that may increase the risk of poor coronavirus disease 2019 (COVID-19) outcomes. There is a paucity of large data at the population level to assess whether patients with AIH have an increased risk of severe diseases. To evaluate the impact of pre-existing AIH on the clinical outcomes of patients with COVID-19. We conducted a population-based, multicenter, propensity score-matched cohort study with consecutive adult patients (≥ 18 years) diagnosed with COVID-19 using the TriNeTx research network platform. The outcomes of patients with AIH (main group) were compared to a propensity score-matched cohort of patients: (1) Without chronic liver disease (CLD); and (2) Patients with CLD except AIH (non-AIH CLD) control groups. Each patient in the main group was matched to a patient in the control group using 1:1 propensity score matching to reduce confounding effects. The primary outcome was all-cause mortality, and secondary outcomes were hospitalization rate, need for critical care, severe disease, mechanical ventilation, and acute kidney injury (AKI). For each outcome, the risk ratio (RR) and confidence intervals (CI) were calculated to compare the association of AIH with the outcome. We identified 375 patients with AIH, 1647915 patients with non-CLD, and 15790 patients with non-AIH CLD with COVID-19 infection. Compared to non-CLD patients, the AIH cohort had an increased risk of all-cause mortality (RR = 2.22; 95%CI: 1.07-4.61), hospitalization rate (RR = 1.78; 95%CI: 1.17-2.69), and severe disease (RR = 1.98; 95%CI: 1.19-3.26). The AIH cohort had a lower risk of hospitalization rate (RR = 0.72; 95%CI: 0.56-0.92), critical care (RR = 0.50; 95%CI: 0.32-0.79), and AKI (RR = 0.56; 95%CI: 0.35-0.88) compared to the non-AIH CLD patients. Patients with AIH are associated with increased hospitalization risk, severe disease, and all-cause mortality compared to patients without pre-existing CLD from the diagnosis of COVID-19. However, patients with AIH were not at risk for worse outcomes with COVID-19 than other causes of CLD.

Disparities in the medical expenditures of patients with cancer and concomitant mental disorder: analyzing the effects of diagnosis sequence order

BackgroundCancer is the leading cause of death in Taiwan. Medical expenditures related to cancer accounted for 44.8% of all major illness insurance claims in Taiwan. Prior research has indicated that the dual presence of cancer and mental disorder in patients led to increased medical burden. Furthermore, patients with cancer and concomitant mental disorder could incur as much as 50% more annual costs than those without. Although previous studies have investigated the utilization of patients with both diseases, the effects of morbidity sequence order on patient costs are, however, uncertain. This study explored medical expenditures linked with the comorbidity of cancer and mental disorder, with a focus on the impact of diagnosis sequence order.MethodsThis population-based retrospective matched cohort study retrieved patients with cancer and mental disorder (aged ≥ 20 years) from the Ministry of Health and Welfare Data Science Center 2005–2015 database. 321,045 patients were divided based on having one or both diseases, as well as on the sequence of mental disorder and cancer diagnosis. Study subjects were paired with comparison counterparts free of both diseases using Propensity Score Matching at a 1:1 ratio. Annual Cost per Patient Linear Model (with a log-link function and gamma distribution) was used to assess the average annual cost, covarying for socio-demographic and clinical factors. Binomial Logistic Regression was used to evaluate factors associated with the risk of high-utilization.ResultsThe “Cancer only” group had higher adjusted mean annual costs (NT$126,198), more than 5-times that of the reference group (e^β: 5.45, p < 0.001). However, after exclusion of patients with non-cancer and inclusion of diagnosis sequence order for patients with cancer and concomitant mental disorder, the post-cancer mental disorder group had the highest expenditures at over 13% higher than those diagnosed with only cancer on per capita basis (e^β: 1.13, p < 0.001), whereas patients with cancer and any pre-existing mental disorder incurred lower expenditures than those with only cancer. The diagnosis of post-cancer mental disorder was significantly associated with high-utilization (OR = 1.24; 95% CI: 1.047–1.469). Other covariates associated with high-utilizer status included female sex, middle to old age, and late stage cancer.ConclusionPresence of mental disorder prior to cancer had a diminishing effect on medical utilization in patients, possibly indicating low medical compliance or adherence in patients with mental disorder on initial treatments after cancer diagnosis. Patients with post-cancer mental disorder had the highest average annual cost. Similar results were found in the odds of reaching high-utilizer status. The follow-up of cancer treatment for patients with pre-existing mental disorders warrants more emphasis in an attempt to effectively allocate medical resources.

A population-based matched cohort study of major congenital anomalies following COVID-19 vaccination and SARS-CoV-2 infection

Evidence on associations between COVID-19 vaccination or SARS-CoV-2 infection and the risk of congenital anomalies is limited. Here we report a national, population-based, matched cohort study using linked electronic health records from Scotland (May 2020-April 2022) to estimate the association between COVID-19 vaccination and, separately, SARS-CoV-2 infection between six weeks pre-conception and 19 weeks and six days gestation and the risk of [1] any major congenital anomaly and [2] any non-genetic major congenital anomaly. Mothers vaccinated in this pregnancy exposure period mostly received an mRNA vaccine (73.7% Pfizer-BioNTech BNT162b2 and 7.9% Moderna mRNA-1273). Of the 6731 babies whose mothers were vaccinated in the pregnancy exposure period, 153 had any anomaly and 120 had a non-genetic anomaly. Primary analyses find no association between any vaccination and any anomaly (adjusted Odds Ratio [aOR] = 1.01, 95% Confidence Interval [CI] = 0.83-1.24) or non-genetic anomalies (aOR = 1.00, 95% CI = 0.81-1.22). Primary analyses also find no association between SARS-CoV-2 infection and any anomaly (aOR = 1.02, 95% CI = 0.66-1.60) or non-genetic anomalies (aOR = 0.94, 95% CI = 0.57-1.54). Findings are robust to sensitivity analyses. These data provide reassurance on the safety of vaccination, in particular mRNA vaccines, just before or in early pregnancy.

Metformin use and associated risk of total joint replacement in patients with type 2 diabetes: a population-based matched cohort study.

It is uncertain whether metformin use is associated with reduced risk of joint replacement in patients with type 2 diabetes mellitus. We aimed to establish whether metformin use was associated with a reduced risk of total knee replacement (TKR) or total hip replacement (THR) among these patients. We selected patients with type 2 diabetes mellitus that was diagnosed between 2000 and 2012 from the Taiwan National Health Insurance Research Database. We used prescription time-distribution matching and propensity-score matching to balance potential confounders between metformin users and nonusers. We assessed the risks of TKR or THR using Cox proportional hazards regression. We included 20 347 participants who were not treated with metformin and 20 347 who were treated with metformin, for a total of 40 694 participants (mean age 63 yr, standard deviation 11 yr; 49.8% were women) after prescription time-distribution matching. Compared with participants who did not use metformin, those who used metformin had lower risks of TKR or THR (adjusted hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.60-0.81 for TKR or THR; adjusted HR 0.71, 95% CI 0.61-0.84 for TKR; adjusted HR 0.61, 95% CI 0.41-0.92 for THR) after adjustment for covariates. Propensity-score matching analyses (10 163 participants not treated with metformin v. 10 163 treated with metformin) and sensitivity analyses using inverse probability of treatment weighting and competing risk regression showed similar results. Metformin use in patients with type 2 diabetes mellitus was associated with a significantly reduced risk of total joint replacement. Randomized controlled clinical trials in patients with osteoarthritis are warranted to determine whether metformin is effective in decreasing the need for joint replacement.

Characteristics and Evolution of Cerebral Aneurysms Among Adults Living With HIV: A Retrospective, Longitudinal Case Series

Objective To describe the characteristics and evolution of cerebral aneurysms in a large cohort of adults living with human immunodeficiency virus (ALWH). Background HIV-associated vasculopathy, which can predispose to cerebral aneurysm development, may result from an inflammatory process whereby HIV viral proteins lead to increased chemoattractant and adhesion particles in the vessel wall. Additionally, adventitial layer inflammation has been shown to be strongly associated with HIV infection and vascular changes that may lead to cerebral aneurysm formation. A recent population-based matched cohort study demonstrated a higher rate of subarachnoid hemorrhage in ALWH. It is important to expand the current understanding of risk factors for aneurysm development and the longitudinal course of patients with HIV-associated vasculopathy to help reduce this source of potential morbidity. Design/Methods The Clinical Data Warehouse was queried for all adult patients evaluated at Boston Medical Center between January 1, 2000, and October 22, 2021 with a history of HIV and at least one cerebral aneurysm. Charts were reviewed for variables including timing of HIV and aneurysm diagnoses, antiretroviral (ART) duration, additional aneurysm risk factors, development of new aneurysms/growth of existing aneurysms, interventions, and clinical outcomes. Results A total of 50 patients (52% female) were identified, including 82 cerebral aneurysms. Forty-six percent of patients with a nadir CD4 count less than 200 cells/mm3 (N = 13) developed new aneurysms or were found to have aneurysm growth over time compared with 29% of patients with a CD4 nadir above 200 cells/mm3 (N = 21). New aneurysms were found or existing aneurysms grew in 67% of those not on ART at time of aneurysm diagnosis (N = 6), 38% of those with inconsistent ART use (N = 8), and 21% of those with consistent ART (N = 19). Conclusions Among ALWH, lower CD4 nadir and inconsistent ART use may contribute to aneurysm formation or growth. Further studies are needed to more thoroughly characterize this trend.

Health service use for young males and females with a mental disorder is higher than their peers in a population-level matched cohort

BackgroundTo inform healthcare planning and resourcing, population-level information is required on the use of health services among young people with a mental disorder. This study aims to identify the health service use associated with mental disorders among young people using a population-level matched cohort.MethodA population-based matched case-comparison retrospective cohort study of young people aged ≤ 18 years hospitalised for a mental disorder during 2005–2018 in New South Wales, Australia was conducted using linked birth, health, and mortality records. The comparison cohort was matched on age, sex and residential postcode. Adjusted rate ratios (ARR) were calculated for key demographics and mental disorder type by sex.ResultsEmergency department visits, hospital admissions and ambulatory mental health service contacts were all higher for males and females with a mental disorder than matched peers. Further hospitalisation risk was over 10-fold higher for males with psychotic (ARR 13.69; 95%CI 8.95–20.94) and anxiety (ARR 11.44; 95%CI 8.70-15.04) disorders, and for both males and females with cognitive and behavioural delays (ARR 10.79; 95%CI 9.30-12.53 and ARR 14.62; 95%CI 11.20-19.08, respectively), intellectual disability (ARR 10.47; 95%CI 8.04–13.64 and ARR 11.35; 95%CI 7.83–16.45, respectively), and mood disorders (ARR 10.23; 95%CI 8.17–12.80 and ARR 10.12; 95%CI 8.58–11.93, respectively) compared to peers.ConclusionThe high healthcare utilisation of young people with mental disorder supports the need for the development of community and hospital-based services that both prevent unnecessary hospital admissions in childhood and adolescence that can potentially reduce the burden and loss arising from mental disorders in adult life.

Childhood diabetes mellitus and early-onset kidney diseases later in life: a nationwide population-based matched cohort study

BackgroundThe empirical evidence remains inconclusive for an association between diabetes mellitus (DM) in children and early-onset kidney disease later in life, and little is known about the effects of DM types (i.e., type 1 diabetes [T1DM] and type 2 diabetes [T2DM]) in childhood on type-specific kidney diseases. We aimed to evaluate the association of childhood DM with overall and type-specific early-onset kidney diseases later in life.MethodsThe population-based matched cohort study included 9356 individuals with DM (T1DM: 8470, T2DM: 886) diagnosed in childhood (< 18 years) who were born between 1977 and 2016, and 93,560 individuals without DM matched on sex and year of birth in Denmark. The main outcomes were overall and type-specific early-onset kidney diseases. The follow-up period of all included participants was from the date of DM diagnosis in the exposure group until the first diagnosis of kidney disease, emigration, or 31 December 2018, whichever came first.ResultsDuring a median follow-up of 13 years, children with DM had a 154% increased risk of early-onset kidney diseases than children without DM (adjusted hazard ratios 2.54, 95% confidence intervals 2.38–2.72), and T1DM (2.48, 2.31–2.67) and T2DM (2.75, 2.28–3.31) showed similar results. Children with DM also had a higher risk of multiple specific kidney diseases including glomerular diseases, renal tubulo-interstitial diseases, renal failure, and urolithiasis. The risks of type-specific kidney diseases including glomerular diseases and renal failure tended to be higher for children with T2DM (glomerular diseases: 5.84, 3.69–9.24; renal failure: 14.77, 8.53–25.59) than those with T1DM (glomerular diseases: 3.14, 2.57–3.83; renal failure: 8.24, 6.66–10.20).ConclusionsChildren with DM had a higher increased risk of early-onset overall and specific kidney diseases later in life. Early prevention and treatment of both T1DM and T2DM in childhood may significantly reduce the risk of kidney diseases later in life.

Sex and age differences in the Multiple Sclerosis prodrome.

Little is known of the potential sex and age differences in the MS prodrome. We investigated sex and age differences in healthcare utilization during the MS prodrome. This was a population-based matched cohort study linking administrative and clinical data from British Columbia, Canada (population = 5 million). MS cases in the 5 years preceding a first demyelinating event ("administrative cohort;" n = 6,863) or MS symptom onset ("clinical cohort;" n = 966) were compared to age-, sex- and geographically-matched controls (n = 31,865/4,534). Negative binomial and modified Poisson models were used to compare the rates of physician visits and hospitalizations per international classification of diseases chapter, and prescriptions filled per drug class, between MS cases and controls across sex and age-groups (< 30, 30-49, ≥50 years). In the administrative cohort, males with MS had a higher relative rate for genitourinary-related visits (males: adjusted Rate Ratio (aRR) = 1.65, females: aRR = 1.19, likelihood ratio test P = 0.02) and antivertigo prescriptions (males: aRR = 4.72, females: aRR = 3.01 P < 0.01). Injury and infection-related hospitalizations were relatively more frequent for ≥50-year-olds (injuries < 30/30-49/≥50: aRR = 1.16/1.39/2.12, P < 0.01; infections 30-49/≥50: aRR = 1.43/2.72, P = 0.03), while sensory-related visits and cardiovascular prescriptions were relatively more common in younger persons (sensory 30-49/≥50: aRR = 1.67/1.45, P = 0.03; cardiovascular < 30/30-49/≥50: aRR = 1.56/1.39/1.18, P < 0.01). General practitioner visits were relatively more frequent in males (males: aRR = 1.63, females: aRR = 1.40, P < 0.01) and ≥50-year-olds (< 30/≥50: aRR = 1.32/1.55, P = 0.02), while differences in ophthalmologist visits were disproportionally larger among younger persons, < 50-years-old (< 30/30-49/≥50: aRR = 2.25/2.20/1.55, P < 0.01). None of the sex and age-related differences in the smaller clinical cohort reached significance (P ≥ 0.05). Sex and age-specific differences in healthcare use were observed in the 5 years before MS onset. Findings demonstrate fundamental heterogeneity in the MS prodromal presentation.

The impact of concussion on school performance in Australian children: a population-based matched cohort study

Introduction: School children who sustain a concussion may experience cognitive and behavioural changes that may impact on their ability to learn, which may lead to poorer educational outcomes. This study aimed to compare academic performance and high school completion of young people hospitalised with concussion and matched peers not hospitalised with concussion.

Association between childhood maltreatment and atopy in the UK: A population based retrospective cohort study.

Childhood maltreatment affects over one in three children worldwide and is associated with a substantial disease burden. This study explores the association between childhood maltreatment and the development of atopic disease. We did a population-based retrospective matched open cohort study using participating general practices between 1st January 1995 and 30th September 2019. Read codes were utilised to identify patients exposed to childhood maltreatment (either suspected or confirmed) who were matched to up to four unexposed patients by age, sex, general practice, and Townsend deprivation quintile. Cox regression analysis was used to calculate adjusted (age, sex, Townsend deprivation quintile) hazard ratios (aHR) for development of atopy (asthma, atopic dermatitis, or allergic rhino conjunctivitis) during follow up in those without atopy at study entry. 183,897 exposed patients were matched to 621,699 unexposed patients. During the follow up period, 18,555 patients (incidence rate (IR) 28.18 per 1000 person-years) in the exposed group developed atopic disease compared to the 68,368 (IR 23.58 per 1000 person-years) in the unexposed group, translating to an adjusted HR of 1.14 (95% CI 1.12-1.15). Notably, the risk of developing asthma was aHR 1.42 (95% CI 1.37-1.46). Associations were more pronounced in analyses restricted to females and confirmed cases of childhood maltreatment only. Considering the substantial health burden associated with childhood maltreatment, it is important to implement public health policies aimed at enhancing: 1) detection and primary prevention of childhood maltreatment, 2) secondary and tertiary prevention interventions to reduce the burden of ill health associated with exposure to maltreatment and 3) clinical awareness of such associations and subsequent knowledge of management. None.

Incidence of cognitive impairment and dementia after hospitalisation for pneumonia: a UK population-based matched cohort study.

Survivors of common infections may develop cognitive impairment or dementia; however, the risk of these conditions in people hospitalised with pneumonia is not well established. A matched cohort study was conducted using Hospital Episode Statistics (HES) data linked to the Clinical Practice Research Database (CPRD). Adults with the first International Classification of Diseases (10th Revision) code for pneumonia recorded in the HES between 1 July 2002 and 30 June 2017 were included, and up to four controls without hospitalisation for pneumonia in the CPRD were matched by sex, age and practice. Cognitive impairment and dementia incidence rates were calculated and survival analysis was performed comparing those hospitalised with pneumonia to the general population. The incidence rates of cognitive impairment and dementia were 18 (95% CI 17.3-18.7) and 13.2 (95% CI 13-13.5) per 1000 person-years among persons previously hospitalised with pneumonia and the matched cohort respectively. People previously hospitalised with pneumonia had 53% higher incidence of cognitive impairment and dementia (adjusted hazard ratio (aHR) 1.53, 95% CI 1.46-1.61) than their matched cohort. The highest incidence was observed within 1 year of hospitalisation for pneumonia compared to the general population (aHR 1.89, 95% CI 1.75-2.05). Age modified the effect of hospitalisation for pneumonia on cognitive impairment and dementia such that the size of effect was stronger in people between 45 and 60 years old (p-value for interaction <0.0001). Cognitive impairment and dementia are more likely to be diagnosed in people who have been hospitalised for pneumonia, especially in the first year after discharge, than in the general population.