Population-based Matched Cohort Study Research Articles

Montelukast does not increase the risk of attention-deficit/hyperactivity disorder in pediatric asthma patients: A nationwide population-based matched cohort study

Attention-deficit/hyperactivity disorder (ADHD) has been linked to pediatric asthma patients treated with montelukast. This study is the first to use a nationwide health insurance research database (NHIRD) to study whether asthmatic children using montelukast are at an increased risk of ADHD. We used data from the Taiwan NHIRD, which is a longitudinal database of one million randomly selected subjects. The enrolled patients were followed up until 2013. Patients younger than and equal to 12 years old with new-onset asthma (ICD-9 CM code 493.X) diagnosed between 1997 and 2013 were enrolled. A multivariate Cox regression analysis was conducted to evaluate the association between montelukast treatment and the risk of ADHD (ICD-9-CM code 314.X). We enrolled a total of 54,487 asthmatic children younger than and equal to 12 years old who had at least one claim of inpatient admission or at least three claims of an ambulatory visit. Montelukast users and match controls were identified by matching age, gender, residence, the comorbidities including allergic rhinitis and atopic dermatitis, admission or emergency department visits due to asthma attack, and index date of starting montelukast in a 1:1 ratio, with 12,806 in the montelukast group and 12,806 in the non-montelukast group. The montelukast group had a similar risk of ADHD (n=632, 4.94%) as the non-montelukast group (n=610, 4.76%) [adjusted hazard ratio 1.04; 95% confidence interval, 0.93 to 1.17]. In children treated with montelukast, high cumulative days of montelukast use did not increase the risk of ADHD. This nationwide population-based cohort study reveals that asthma children treated with montelukast were not at an increased risk of developing ADHD. Nevertheless, validation of our retrospective survey requires further prospective study.

Advanced Access scheduling in general practice and use of primary care: a Danish population-based matched cohort study.

BackgroundAdvanced access scheduling (AAS) allows patients to receive care from their GP at the time chosen by the patient. AAS has shown to increase the accessibility to general practice, but little is known about how AAS implementation affects the use of in-hours and out-of-hours (OOH) services.AimTo describe the impact of AAS on the use of in-hours and OOH services in primary care.Design & settingA population-based matched cohort study using Danish register data.MethodA total of 161 901 patients listed in 33 general practices with AAS were matched with 287 837 reference patients listed in 66 reference practices without AAS. Outcomes of interest were use of daytime face-to-face consultations, and use of OOH face-to-face and phone consultations in a 2-year period preceding and following AAS implementation.ResultsNo significant differences were seen between AAS practices and reference practices. During the year following AAS implementation, the number of daytime face-to-face consultations was 3% (adjusted incidence rate ratio [aIRR] = 1.03; 95% confidence interval [CI] = 0.99 to 1.07) higher in the AAS practices compared with the number in the reference practices. Patients listed with an AAS practice had 2% (aIRR = 0.98; 95% CI = 0.92 to 1.04) fewer OOH phone consultations and 6% (aIRR = 0.94; 95% CI = 0.86 to 1.02) fewer OOH face-to-face consultations compared with patients listed with a reference practice.ConclusionThis study showed no significant differences following AAS implementation. However, a trend was seen towards slightly higher use of daytime primary care and lower use of OOH primary care.

Annals for Educators - 3 November 2020.

Annals for Educators - 3 November 2020.

Effects of socioeconomic status on mortality after Parkinson's disease: A nationwide population-based matched cohort study in Korean populations

IntroductionTo evaluate the mortality rate and impact of SES on mortality in PD using a nationwide cohort in Korea. MethodsWe selected patients diagnosed with PD (ICD-10 code: G20) and registration code for PD (V124) in the program for rare intractable diseases between 2004 and 2015. After that, atypical parkinsonism was excluded. A matched cohort of individuals without PD were enrolled by randomly matching patients by sex, age, and year of diagnosis to the PD group with a ratio of 1:9. Cox proportional hazard models were used to identify the effects of SES on mortality using Hazard Ratios and 95% confidence intervals. ResultsIn total, 26,570 participants were enrolled. The mortality rate was 30.37% in PD cohort and 16.69% in the comparison cohort. According to income level, PD patients in low-middle group revealed significantly decreased HRs of 0.704 (95% CI, 0.533–0.930) compared to those in the lowest group. The medical aid group showed an increased mortality rate (HR = 1.552, 95% CI, 1.191–2.021) compared to the national health insurance group. In the subgroup analyses, medical aid was associated with mortality only in PD with female (HR = 1.740, 95% CI, 1.242–2.438) or aged 60–79 years (HR = 1.434, 95% CI 1.005–2.045). There was no significant difference in mortality rate according to residential area in PD. ConclusionsIn Korea, individual level low SES including income level and insurance type were significantly associated with increased mortality, whereas regional level SES (residential area) was not related with mortality on PD.

Are anticholinergic medications used for overactive bladder associated with new onset depression? A population-based matched cohort study.

Prior research has suggested that anticholinergic medications used for overactive bladder are associated with depression. Our objective was to test this hypothesis by comparing rates of new onset depression among anticholinergic medication users and those who were prescribed an alternative class of overactive bladder medication. We used administrative data records from the province of Ontario, Canada and a matched cohort design. We matched patients who were newly prescribed an oral anticholinergic to those prescribed a beta-3 agonist medication in a 2:1 ratio which included a propensity score that incorportated 75 baseline characteristics. The primary outcome of depression was measured using a validated definition, and the at-risk period for our outcome of interest was between the initial date the prescription was filled, and up to 3 months after the end of continuous usage of that medication. Hazard ratios (HRs) were estimated using Cox proportional hazards regression. We matched 23 622 beta-3 agonist users (mirabegron) to 47 324 anticholinergic users (most commonly tolterodine, oxybutynin, and solifenacin). The rate of depression was similar among beta-3 agonist users (11.2 per 1000 patient-years) and anticholinergic users (11.9 per 1000 patient-years). In our primary analysis, the risk of depression among anticholinergic users was not significantly different compared to beta-3 agonist users (HR 1.08 [95% CI 0.92-1.28, P = .35]). Contrary to a previous report, overactive bladder anticholinergic medications do not appear to be associated with new onset depression.

Assessment of the Risk of Psychiatric Disorders, Use of Psychiatric Hospitals, and Receipt of Psychiatric Medication Among Patients With Lyme Neuroborreliosis in Denmark

The association of Lyme neuroborreliosis with the development of psychiatric disease is unknown and remains a subject of debate. To investigate the risk of psychiatric disease, the percentage of psychiatric hospital inpatient and outpatient contacts, and the receipt of prescribed psychiatric medications among patients with Lyme neuroborreliosis compared with individuals in a matched comparison cohort. This nationwide population-based matched cohort study included all residents of Denmark who received a positive result on an intrathecal antibody index test for Borrelia burgdorferi (patient cohort) between January 1, 1995, and December 31, 2015. Patients were matched by age and sex to a comparison cohort of individuals without Lyme neuroborreliosis from the general population of Denmark. Data were analyzed from February 2019 to March 2020. Diagnosis of Lyme neuroborreliosis, defined as a positive result on an intrathecal antibody index test for B burgdorferi. The 0- to 15-year hazard ratios for the assignment of psychiatric diagnostic codes, the difference in the percentage of psychiatric inpatient and outpatient hospital contacts, and the difference in the percentage of prescribed psychiatric medications received among the patient cohort vs the comparison cohort. Among 2897 patients with Lyme neuroborreliosis (1646 men [56.8%]) and 28 970 individuals in the matched comparison cohort (16 460 men [56.8%]), the median age was 45.7 years (interquartile range [IQR], 11.5-62.0 years) for both groups. The risk of a psychiatric disease diagnosis and the percentage of hospital contacts for psychiatric disease were not higher among patients with Lyme neuroborreliosis compared with individuals in the comparison cohort. A higher percentage of patients with Lyme neuroborreliosis compared with individuals in the comparison cohort received anxiolytic (7.2% vs 4.7%; difference, 2.6%; 95% CI, 1.6%-3.5%), hypnotic and sedative (11.0% vs 5.3%; difference, 5.7%; 95% CI, 4.5%-6.8%), and antidepressant (11.4% vs 6.0%; difference, 5.4%; 95% CI, 4.3%-6.6%) medications within the first year after diagnosis, after which the receipt of psychiatric medication returned to the same level as the comparison cohort. In this population-based matched cohort study, patients with Lyme neuroborreliosis did not have an increased risk of developing psychiatric diseases that required hospital care or treatment with prescription medication. The increased receipt of psychiatric medication among patients with Lyme neuroborreliosis within the first year after diagnosis, but not thereafter, suggests that most symptoms associated with the diagnosis subside within a short period.

Health service use among Manitobans with alcohol use disorder: a population-based matched cohort study.

Alcohol is the drug most commonly used by Canadians, with multiple impacts on health and health service use. We examined patterns of short- and long-term health service use among people with a diagnosis of alcohol use disorder. In this retrospective matched cohort study, we used population-based administrative data from the province of Manitoba, Canada, to identify individuals aged 12 years or older with a first indication of alcohol use disorder (index date) in the period 1990 to 2015. We matched cases (those with diagnosis of alcohol use disorder) to controls (those without this diagnosis), at a 1:5 ratio, on the basis of age, sex, geographic region and income quintile at the index date. The outcome measures were inpatient hospital admission, outpatient physician visits, emergency department visits and use of prescription medications. We modelled crude rates using generalized estimating equations with either a negative binomial or a Poisson distribution RESULTS: We identified 53 410 people with alcohol use disorder and 264 857 matched controls. All outcomes occurred at a higher rate among people with the disorder than among controls. For example, during the year of diagnosis, the rate ratio for hospital admission was 4.0 (95% confidence interval [CI] 3.9-4.2) for women and 4.5 (95% CI 4.4-4.7) for men. All rates of health service use peaked close to the index date, but remained significantly higher among people with alcohol use disorder than among controls for 20 years. Among people with alcohol use disorder, the most commonly filled prescriptions were for psycholeptics, whereas among controls, the most commonly filled prescriptions were for sex hormones (women) and antihypertensives (men). Compared with controls, people with alcohol use disorder used significantly more health services from the time of diagnosis and over the next 20 years. This finding highlights the need for better detection and early intervention to reduce the need for acute and emergency care, as well as the need for improved management of alcohol use disorder over the longer term.

The impact of systemic lupus erythematosus on the risk of infection after total hip arthroplasty: a nationwide population-based matched cohort study

BackgroundWe aimed to assess the impact of systemic lupus erythematosus (SLE) on the risk of infection after total hip arthroplasty (THA).MethodsWe identified patients undergoing primary THA (1996–2013) in Taiwan National Health Insurance Research Database (NHIRD). Patients were then divided into the SLE and control groups according to the diagnosis of SLE. We used 1:1 propensity score to match the control to the SLE group by age, sex, and comorbidities. The primary outcome was infection, including early and late superficial wound infection and periprosthetic joint infection (PJI). The secondary outcome was in-hospital complications.ResultsWe enrolled 325 patients in each group. In the primary outcome, the incidence of early superficial wound infection and PJI was comparable between the SLE and matched-control group. However, the incidence of late superficial wound infection and PJI in the SLE group was higher than that in matched-control group (11.4% vs. 5.5%, P = 0.01; 5.2% vs 2.2%, P = 0.04, respectively). Furthermore, the SLE group had a higher risk for late superficial wound infection and PJI (hazard ratio = 2.37, 95% confidence interval (CI) 1.35–4.16; HR = 2.74, 95% CI 1.14–6.64, respectively) than the matched-control. Complications other than infection and in-hospital mortality cannot be compared because of very low incidence.ConclusionsSLE is a risk factor for developing late superficial wound infection and PJI, but not for early postoperative complications following THA. Clinical presentations should be monitored to avoid misdiagnosis of PJI in SLE patients after THA.

Does the NHS Diabetes Prevention Programme prevent diabetes? A population-based matched cohort study

Abstract Background To reduce the incidence of type 2 diabetes (T2DM) in England, the National Health Service piloted the Diabetes Prevention Programme (DPP). The DPP aims to prevent T2DM by providing high-risk adults with access to 13 face-to-face sessions over nine months that focus on diet and weight management. The DPP has been shown to improve intermediate outcomes for T2DM prevention (weight loss and glycated haemoglobin (HbA1c) reduction). However, there is a lack of evidence examining incident T2DM as the outcome. Methods We conducted a retrospective observational cohort study using linked electronic health records from primary (Clinical Practice Research Datalink) and secondary (Hospital Episode Statistics) care for June 2016 to January 2019. We compared rates of new T2DM diagnoses among eligible adults who were referred to the DPP with rates for propensity score-matched (ratio of 1:4) controls who were eligible for the DPP but were not invited. DPP eligibility was defined as having HbA1c levels of 42-47 mmol/mol or fasting plasma glucose (FPG) levels of 5.5-6.9 mmol/L. Adults with pre-existing T2DM were excluded. Time to the first record of T2DM was modelled using Cox regression with age, alcohol intake, body mass index, ethnicity, sex, HbA1c, index of multiple deprivation and smoking status included as covariates. Results We identified 2205 individuals who participated in the DPP and 8820 matched controls with a similar breakdown in age, sex, HbA1c and FPG. During the 2.5-year study period, 4.13% of DPP individuals developed T2DM vs 6.42% of controls. Our results indicate that DPP referrals were associated with a 59% reduction T2DM incidence rates [adjusted hazard ratio=0.41;95%CI=0.38-0.44]. Conclusions This is the first study to investigate the impact of the DPP on T2DM, relative to usual care. Our results provide support for the effectiveness of DPP in preventing T2DM onset and are compatible with findings for similar interventions in other settings. Key messages The evidence suggests that providing consistent face-to-face sessions which concentrate on diet and weight management can reduce short-term T2DM incidences in high-risk adults. With a 59% reduction in T2DM rates in DPP referees relative to eligible adults who were not referred, the DPP is effective in reducing short-term T2DM incidences in high-risk adults.

Trajectories of sickness absence and disability pension in colorectal cancer: a Swedish cohort study

Abstract Background Working-aged colorectal cancer (CRC) patients have a much better survival nowadays, indicating the importance of their future work situation. We aimed to investigate trajectories of sickness absence and disability pension (SADP) days before and after CRC diagnosis and in references, and risk factors associated with different trajectories. Methods A longitudinal, population-based matched cohort study of 4735 CRC survivors in Sweden aged 19-62 when first diagnosed with CRC in 2008-2011, and 18,230 matched references was conducted, using microdata linked from several nationwide registers. The annual SADP net days for 2 years before through 5 years after diagnosis date were computed. A group-based trajectory model was used to depict SADP trajectories. Associations between trajectory membership, and sociodemographic and clinical variables were tested by chi2 test and multinomial logistic regression. Results Four trajectories of SADP days/year for CRC survivors were identified: “only increase around diagnosis” (52% of all, n = 2481), “slight increase after diagnosis” (27%), “high then decrease moderately after diagnosis” (13%), and “constantly very high” (8%). Educational level (R2=0.022), Charlson's Comorbidity Index (R2=0.029), and prediagnostic mental disorders (R2=0.066) were the strongest factors determining the SADP trajectory groups. In references, three trajectories (”constantly low” (80% of all), “constantly moderate and decrease gradually” (12%), and “very high then decrease overtime” (8%)) were identified. Conclusions Approximately 80% of CRC survivors return to a low level of SADP (0-60 days/year) at 5 years postdiagnosis. Prediagnostic status of mental disorders, somatic comorbidity, and low educational level are good indicators of future high SADP levels for CRC survivors. Key messages Most of working-age colorectal cancer survivors have low levels of sickness absence and disability pension days five years after their diagnosis. Trajectory analyses based on population-based register data can be used as a good approach in understanding future work situation regarding sick leave among working-age cancer survivors.

Constipation and risk of cardiovascular diseases: a Danish population-based matched cohort study.

ObjectivesTo assess the risks of myocardial infarction, stroke, peripheral artery disease, venous thromboembolism, atrial fibrillation or atrial flutter and heart failure in patients with constipation compared with a general population cohort.DesignPopulation-based matched cohort study.SettingAll Danish hospitals and hospital outpatient clinics from 2004 to 2013.ParticipantsPatients with a constipation diagnosis matched on age, sex and calendar year to 10 individuals without constipation from the general population.Main outcomes measuresComorbidity-adjusted and medication-adjusted hazard ratios (aHRs) for cardiovascular outcomes based on Cox regression analysis.Results83 239 patients with constipation were matched to 832 384 individuals without constipation. The median age at constipation diagnosis was 46.5% and 41% were men. Constipation was strongly associated with venous thromboembolism (aHR 2.04, 95% CI 1.89 to 2.20), especially splanchnic venous thrombosis (4.23, 95% CI 2.45 to 7.31). Constipation was also associated with arterial events, including myocardial infarction (1.24, 95% CI 1.14 to 1.35), ischaemic stroke (1.50, 95% CI 1.41 to 1.60), haemorrhagic stroke (1.46, 95% CI 1.26 to 1.69), peripheral artery disease (1.34, 95% CI 1.20 to 1.50), atrial fibrillation or atrial flutter (1.27, 95% CI 1.20 to 1.34) and heart failure (1.52, 95% CI 1.42 to 1.62). The associations were strongest during the first year after the constipation diagnosis and strengthened with an increased number of laxative prescriptions.ConclusionsConstipation was associated with an increased risk of several cardiovascular diseases, in particular venous thromboembolism.

Costs Associated with Nontuberculous Mycobacteria Infection, Ontario, Canada, 2001–2012

To determine incidence-based healthcare costs attributable to nontuberculous mycobacterial (NTM) pulmonary disease (PD) and NTM pulmonary isolation (PI), from the healthcare payer perspective, we conducted a population-based matched cohort study in Ontario, Canada. We established cohorts of patients with incident NTM-PD and NTM-PI during 2001–2012 by using individually linked laboratory data and health administrative data, matched to unexposed persons from the general population. To estimate attributable costs for acute and long-term illness, we used a phase-of-care approach. Costs were stratified by age, sex, and healthcare resource, and reported in 2018 Canadian dollars (CAD) and US dollars (USD), standardized to 10 days. Costs were highest during the before-death phase (NTM-PD CAD $1,352 [USD $1,044]; NTM-PI CAD $731 [USD $565]). The cumulative mean attributable 1-year costs were CAD $14,953 (USD $11,541) for NTM-PD and CAD $8,729 (USD $6,737) for NTM-PI. Costs for patients with NTM-PD and NTM-PI were higher than those for unexposed persons.

Association Between Bariatric Surgery and All-Cause Mortality: A Population-Based Matched Cohort Study in a Universal Health Care System.

Mortality after bariatric surgery has been previously studied, but cohort selection bias, completeness of follow-up, and collection of confounders have limited the inference of results. To determine the association between bariatric surgery and all-cause mortality. Population-based matched cohort study. Ontario, Canada. 13679 patients who underwent bariatric surgery from January 2010 to December 2016 and 13679 matched nonsurgical patients. Bariatric surgery. The primary outcome was all-cause mortality, with cause-specific mortality as the secondary outcome. Patients were matched according to age, sex, body mass index, and diabetes duration. 13679 patients who underwent bariatric surgery were matched to 13679 nonsurgical patients. After a median follow-up of 4.9 years, the overall mortality rate was 1.4% (n= 197) in the surgery group and 2.5% (n= 340) in the nonsurgery group, with a lower adjusted hazard ratio (HR) of overall all-cause mortality (HR, 0.68 [95% CI, 0.57 to 0.81]). Patients aged 55 years or older had an absolute risk reduction of 3.3% (CI, 2.3% to 4.3%), with a lower HR of mortality in the surgery group (HR, 0.53 [CI, 0.41 to 0.69]). Observed relative effects were similar across sex; however, the observed association in absolute terms was greater in men. Surgery also was associated with lower cardiovascular mortality (HR, 0.53 [CI, 0.34 to 0.84]) and lower cancer mortality (HR, 0.54 [CI, 0.36 to 0.80]). The observational design limits causal inference. Bariatric surgery was associated with substantially lower all-cause, cardiovascular, and cancer mortality. The lowered observed mortality of surgery was significant across most subgroups. The largest absolute effects were for men and patients aged 55 years or older. Ontario Bariatric Network.

Incidence of osteoporosis and fragility fractures in asthma: a UK population-based matched cohort study.

Osteoporosis and fragility fractures are associated with corticosteroids which are the mainstay treatment for asthma; however, these bone comorbidities within asthma need to be better described. A matched cohort study was conducted using the UK Clinical Practice Research Database (CPRD). Adults with an incident asthma code were identified and matched, with up to four randomly selected people without asthma, by age, sex and practice. Osteoporosis and fragility fracture incidence rates were calculated, and Cox regression was performed comparing hazard rates to the general population. We report the impact of age, sex, glucocorticoids and the risk of specific fractures. Patients with asthma had a higher risk of osteoporosis (adjusted hazard ratio (aHR) 1.18, 95% CI 1.13-1.23) and were 12% (aHR 1.12, 95% CI 1.07-1.16) more likely to sustain fragility fractures than the general population. Age modified the effect of asthma on osteoporosis and fragility fractures, such that the effect was stronger in younger people (pinteraction<0.0001). The vertebra (aHR 1.40, 95% CI 1.33-1.48) and forearm/wrist (aHR 1.27, 95% CI 1.22-1.32) were the sites linked with a larger incidence. A dose-response relationship between oral corticosteroids (OCS) and osteoporosis was observed, whereas the risk of fragility fractures increased in those with six or more OCS courses per year. Regular use of inhaled corticosteroids (ICS) increased the risk of both bone conditions. Patients with asthma are more likely to develop osteoporosis or sustain fragility fractures than the general population, with a particular concern in younger people and those more frequently using OCS and ICS.

Increased risk of perinatal complications in women with cirrhosis: a population-based matched cohort study

Increased risk of perinatal complications in women with cirrhosis: a population-based matched cohort study

Risk of chronic kidney disease in patients with kidney stones\u2014a nationwide cohort study

BackgroundChronic kidney disease (CKD) and kidney stones are common in Taiwan; in particular, CKD has a high prevalence but low self-awareness rate. CKD-related risk factors such as diabetes, hypertension, and nephrotoxic drugs are well-known and uncontested; however, kidney stones are relatively less studied and easily overlooked as a risk factor. The objective of this study was to investigate whether kidney stones are a risk factor for CKD.MethodsWe conducted a nationwide population-based matched cohort study to assess the risk of incident CKD in people with kidney stones. Data on incident stones formers in the year 2001—excluding those with a history of CKD—were obtained from Taiwan’s National Health Insurance database. Stone formers were matched (1:4) to control subjects according to sex, age, and index date. The total observation period of the study was 10 years, and the primary end-point was the occurrence of CKD. Student’s t-test and Chi-squared test were used to compare continuous and categorical data, respectively. Logistic regression was used to calculate the odds ratio of kidney stone patients with incident CKD relative to the control group. Cox proportional hazard regression model was used to obtain the hazard ratio for development of incident CKD among patients with kidney stones.ResultsThe incidence of CKD in the kidney stone cohort was 11.2%, which was significantly higher than that of the control group (P < .001). Survival analysis showed that the stones cohort was 1.82 times more likely to experience CKD than the controls. Age, sex, hypertension, diabetes mellitus, and hyperlipidemia increased the risk of CKD incidence (1.04, 1.27, 1.55, 3.31, and 1.25 times, respectively).ConclusionKidney stones are a definite risk factor for CKD; therefore, patients with stones are suggested to undergo regular renal function monitoring and receive appropriate treatment to avoid CKD.

The Occurrence of Metabolic Risk Factors Stratified by Psoriasis Severity: A Swedish Population-Based Matched Cohort Study.

PurposeTo assess the relative risk of metabolic risk factors in patients stratified by psoriasis severity compared with population controls.Patients and MethodsA retrospective cohort study was conducted using national Swedish registers. Adult patients with psoriasis were selected if they had a dispensing of anti-psoriasis prescription (2007–2013) and at least one diagnosis within five years before the dispensing date. The patients with psoriasis were matched 1:10 to controls from the general population on birth year, sex, and county. The cohort was further divided into three disease severity groups (mild, moderate, or severe) based on their dispensed anti-psoriasis medication. Subjects were followed from the index date until censoring. We applied flexible parametric modeling to understand the risks of the incident comorbidities hypertension, hypercholesterolemia, and diabetes mellitus among patients with psoriasis from 6 months through 10 years. Hazard ratios and predicted risk (ie, 1 minus the survival probability) of comorbidities were reported.ResultsThe hazard of hypertension, hypercholesterolemia, and diabetes mellitus is higher among psoriasis patients compared with population controls, and the hazard ratio increases with psoriasis severity. For example, HRs of hypertension for patients with mild, moderate, and severe psoriasis are 1.29 (95% CI: 1.27–1.32), 1.35 (95% CI: 1.32–1.38), and 1.73 (95% CI: 1.64–1.82), respectively. The predicted risk of hypertension, hypercholesterolemia, and diabetes mellitus among patients with severe psoriasis at year ten was 0.58 (95% CI: 0.56, 0.59), 0.33 (95% CI: 0.32, 0.35), and 0.21 (95% CI: 0.20, 0.23), respectively, while it was 0.42 (0.41, 0.43), 0.23 (0.22, 0.23), 0.11 (0.10, 0.11) among controls, respectively. The predicted risk at year ten was similar among patients with mild or moderate psoriasis.ConclusionThe HRs and predicted risks of metabolic risk factors are higher among patients with psoriasis compared with matched controls and are more prominent among the severe psoriasis group.

Risk of infections in patients with myeloproliferative neoplasms-a population-based cohort study of 8363 patients.

Infections are a common complication in patients with many hematologic malignancies, however, whether patients with myeloproliferative neoplasms (MPN) also are at an increased risk of infections is largely unknown. To assess the risk of serious infections, we performed a large population-based matched cohort study in Sweden including 8 363 MPN patients and 32,405 controls using high-quality registers between the years 1992-2013 with follow-up until 2015. The hazard ratio (HR) of any infection was 2.0 (95% confidence interval 1.9-2.0), of bacterial infections 1.9 (1.8-2.0), and of viral infections 2.1 (1.9-2.3). One of the largest risk increases was that of sepsis, HR 2.6 (2.4-2.9). The HR of any infection was highest in primary myelofibrosis 3.7 (3.2-4.1), and significantly elevated in all MPN subtypes; 1.7 (1.6-1.8) in polycythemia vera and 1.7 (1.5-1.8) in essential thrombocythemia. There was no significant difference in risk of infections between untreated patients and patients treated with hydroxyurea or interferon-α during the years 2006-2013. These novel findings of an overall increased risk of infections in MPN patients, irrespective of common cytoreductive treatments, suggest the increased risk of infection is inherent to the MPN.

How "benign" is cutaneous mastocytosis? A Danish registry-based matched cohort study.

BackgroundThere are limited estimates of the incidence rates (IRs) of mastocytosis, and only a few studies have addressed the long-term consequences of living with these diagnoses. Previous reports have shown that systemic mastocytosis is associated with leukemic transformations and an increased risk of death as opposed to cutaneous mastocytosis (CM) and indolent systemic mastocytosis (ISM), which have benign diagnoses with life expectancy rates similar to those of the background population.ObjectiveThis study aimed to analyze the incidence and mortality of mastocytosis.MethodsA population-based matched cohort study of patients with mastocytosis between 1 January 1, 1977 and 31 December 31, 2014 was identified from the Danish National Health Registries. IRs of CM, ISM, and pediatric mastocytosis were highlighted. Survival estimates were compared with those of a healthy background population, using a Cox proportional hazard model.ResultsA total of 1461 patients with mastocytosis were identified. The annual IR of overall mastocytosis was 1.1 per 100,000 person years (95% confidence interval [CI], 1.0–1.2). Among children, the IR was 1.8 per 100,000 person years (95% CI, 1.6–2.1). The prevalence of any comorbidity was twice as high among patients with mastocytosis compared with the population without mastocytosis (odds ratio: 2.1; 95% CI, 1.8–2.5). The Charlson Comorbidity Index–adjusted mortality among adult patients with mastocytosis was HRCutaneous Mastocytosis 1.2 (95% CI, 0.8–1.9), HRIndolent Systemic Mastocytosis 1.9 (95% CI 1.4–2.5), and HRSystemic Mastocytosis 4.2 (95%, CI 1.9–9.4), respectively.ConclusionBased on an entire nation, with free health care at the point of access, we estimated an annual IR of mastocytosis and its subgroups. We discovered that patients with ISM had an increased risk of death compared with the general population. Our data supported the overall benign nature of CM diagnosed after age 2 years.

Evaluating the Risk of Macrovascular Events and Mortality Among People With Multiple Sclerosis in England

People with multiple sclerosis (MS) are associated with an increased risk of cardiovascular disease and mortality; however, evidence from population-based studies is sparse. To assess whether the risk of macrovascular events and mortality differs among people with MS compared with a matched population without MS in England. A population-based retrospective matched cohort study was conducted in general practices registered with the Clinical Practice Research Datalink in England between January 1, 1987, and September 30, 2018, with a mean (SD) follow-up of 11.3 (6.5) years. A total of 12 251 patients with MS were matched with up to 6 people without MS (n = 72 572) by age, sex, and general practice. People with 3 or more diagnoses of MS recorded during the study period were included. The first MS diagnosis was considered as index date. Multiple sclerosis status. Analyses were also stratified by sex. Main outcomes were acute coronary syndrome, cerebrovascular disease, any macrovascular disease (including peripheral arterial disease), and mortality (all-cause mortality and cardiovascular disease-specific mortality). Cox proportional hazards regression and Fine and Gray proportional subhazard regression models were used to assess differences in rates. A total of 12 251 people with MS (66.9% women; mean [SD] age, 44.9 [13.3] years) were matched with 72 572 people without MS (69.8% women; mean [SD] age, 44.9 [13.3] years). As compared with people without MS, people with MS were associated with a 28% increased hazard of acute coronary syndrome (hazard ratio [HR], 1.28; 95% CI, 1.09-1.51), 59% increased hazard of cerebrovascular disease (HR, 1.59; 95% CI, 1.32-1.92), 32% increased hazard of any macrovascular disease (HR, 1.32; 95% CI, 1.15-1.52), 3.5-fold increased hazard of all-cause mortality (HR, 3.46; 95% CI, 3.28-3.65), and 1.5-fold increased hazard in cardiovascular disease mortality (HR, 1.47; 95% CI, 1.27-1.71). Differences in macrovascular events were more pronounced among women than men. Mortality risk was also higher for women than men. Treatment with lipid-lowering medications (mainly statins) was associated with lower mortality rates among people with MS. This study suggests that MS is associated with an increased risk of cardiovascular and cerebrovascular disease that is not completely accounted for by traditional vascular risk factors. Given the adverse effects of these comorbidities on outcomes in patients with MS, further investigation is needed.