Nationwide Population-based Matched Cohort Study Research Articles

Mental Health Among Patients with Non-Hodgkin Lymphoma: A Danish Nationwide Study of Psychotropic Drug Use in 7,201 Patients and 36,005 Matched Comparators

Introduction: A cancer diagnosis is associated with profound psychological distress that potentially can lead to mental health problems such as depression and anxiety. Non-Hodgkin lymphomas (NHLs) are a heterogenous group of indolent and aggressive cancer diseases with high variability in treatment selections and patient outcomes. Some patients are chronically ill with recurrent need for mild chemotherapy whereas others face immediately life-threatening, yet curable disease. To gain valuable insights into the psychological distress associated with NHLs, the present study investigated the incident psychotropic drug (PD - antidepressants, anxiolytics, and antipsychotics) use, contact patterns to psychiatric departments, and intentional self-harm (including suicide) in Danish NHL patients relative to sex- and age matched individuals from the background population.Methods: The study was carried out as a nationwide population-based matched cohort study based on prospectively collected data from several Danish registries. All adult NHL patients (≥18 years) diagnosed between 2005 and 2015 were identified in the Danish Lymphoma Registry and included if they had not been treated with any kind of PD within the last 10 years prior to date of NHL diagnosis (index date). NHL patients were matched on age and sex with five random comparators from the Danish background population on the index date. Comparators had to be alive and without PD use 10 years prior to the index date. Incident PD use was defined as first redeemed prescription of PD after index date. Prescriptions were captured in the National Prescription Registry and described by cumulative incidences using the Aalen-Johansen estimator with death and NHL relapse as competing risk. Contacts with psychiatric departments and registration of intentional self-harm or completed suicide were captured in the Danish National Patient Registry. Patients were subcategorized according to type of lymphoma (Table 1).Results: In total, 7,201 NHL patients and 36,005 matched comparators were included (median follow-up 7.1 years). Follicular lymphoma (FL, 44.4%) and diffuse large B-cell lymphoma (DLBCL, 41.0%) were the most common subtypes (Table 2). Two-year cumulative incidence of PD use was higher in NHL patients overall (16.2%, 95%CI 15.4-17.0%) compared to matched comparators (5.7%, 95%CI 5.5-5.9%). Patients with aggressive NHL subtypes tended to have the highest incidence of PD use (Figure 1). Antidepressants (two-year cumulative incidence, 9.0%, 95%CI 8.4-9.6) and anxiolytics (8.2%, 95%CI 7.6-8.8) were the most used PDs in all NHL subtypes. The risk of PD use was higher in the first years following diagnosis, but except for patients with indolent NHL subtypes, the risk of PD use normalized over time to that of the background population. As for the risk of any psychiatric department contacts, there was no difference in two-year cumulative incidences between NHL patients (range 0.6-0.9%) and the matched comparators (range 0.6%-0.9%), whereas the two-year cumulative incidence of intentional self-harm and suicide was slightly higher for NHL patients (0.3%) compared to the matched comparators (0.2%, p=0.01).Conclusion: This study suggests that NHL patients have a significantly higher risk of mental health problems compared to the Danish background population, (when) using PD prescriptions as a proxy measure. The risk of intentional self-harm and completed suicide was also higher, but numerical differences were very small. Overall, the results emphasize the need for directing clinical attention on mental health in newly diagnosed NHL patients and screening for relevant symptoms during follow-up to provide best possible support to patients suffering from anxiety and depression. [Display omitted] DisclosuresØvlisen: Abbvie: Other: Travel expenses. Kragholm: Novartis: Honoraria. Nielsen: Lundbeck: Honoraria, Other: Investigator, Research Funding; Otsuka Pharmaceuticals: Honoraria, Other: Prior Advisor, Research Funding; Bristol-Myers Squibb: Honoraria; Astra Zeneca: Honoraria, Other: Prior advisor; Janssen & Cilag: Honoraria, Other: Investigator; Servier: Honoraria; Teva A/S: Honoraria; Eli Lilly: Honoraria, Other: Prior Advisor; Takeda: Other: Prior advisor; Medivir: Other; Boehringer: Other: Investigator. Brown: BMS: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Novartys: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees. Dahl-Soerensen: Takeda: Other: Travel grant. Frederiksen: Novartis: Research Funding; Alexion: Research Funding; Gilead: Research Funding; Abbvie: Research Funding; Janssen Pharmaceuticals: Research Funding. Mannering: Novartis: Research Funding; Swedish Orphan Biovitrum (SOBI): Membership on an entity's Board of Directors or advisory committees. Jørgensen: Gilead: Consultancy; Roche: Consultancy; Novartis: Consultancy; Celgene: Consultancy. Clausen: Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel expences ASH 2019; Gilead: Consultancy, Other: Travel expences 15th ICML . El-Galaly: ROCHE Ltd: Ended employment in the past 24 months; Abbvie: Other: Speakers fee.

Fractures and Osteoporosis in Patients With Diabetes With Charcot Foot.

Charcot foot is a serious complication of diabetes, with degeneration of the bones and joints in the foot and ankle. It is unknown whether patients with diabetes with a Charcot foot have an increased risk of osteoporosis and fractures. The aim of this study was to investigate whether patients with diabetes with a Charcot foot have an increased risk of fracture and/or osteoporosis compared with patients with diabetes without Charcot foot. A Danish register-based, nationwide population-based matched cohort study was conducted. During 1995-2018, we identified 1,602 patients with diabetes with Charcot foot and matched them on sex and date of diagnosis of diabetes with 16,296 patients with diabetes without Charcot foot. We used logistic regression to estimate odds ratios (ORs) with 95% CIs for fracture and osteoporosis. Information about exposure, outcome, and comorbidities was retrieved from the Danish National Patient Register. Diabetes patients with Charcot foot had higher risk of fractures compared with those without Charcot foot (i.e., ORs for any fracture, lower-leg fracture, foot fracture, and osteoporotic fracture were 1.8 [95% CI 1.6-2.0], 2.4 [2.0-2.8], 2.9 [2.6-3.3], and 1.3 [1.1-1.4], respectively). Furthermore, patients with diabetes with Charcot foot had higher risk of osteoporosis compared with the patients without Charcot foot, with an OR of 1.3 (95% CI 1.1-1.5). Patients with diabetes with a Charcot foot have an increased risk of fractures and osteoporosis compared with patients with diabetes without a Charcot foot.

Absence of Association between Previous Mycoplasma pneumoniae Infection and Subsequent Myasthenia Gravis: A Nationwide Population-Based Matched Cohort Study.

Mycoplasma pneumoniae (M. pneumoniae) is not only one of the most common pathogenic bacteria for respiratory infection but also a trigger for many autoimmune diseases. Its infection process shared many similarities with the pathogenesis of myasthenia gravis (MG) at cellular and cytokine levels. Recent case reports demonstrated patients present with MG after M. pneumoniae infection. However, no epidemiological studies ever looked into the association between the two. Our study aimed to investigate the relationship between M. pneumoniae infection and subsequent development of MG. In this population-based retrospective cohort study, the risk of MG was analyzed in patients who were newly diagnosed with M. pneumoniae infection between 2000 and 2013. A total of 2428 M. pneumoniae patients were included and matched with the non-M. pneumoniae control cohort at a 1:4 ratio by age, sex, and index date. Cox proportional hazards regression analysis was applied to analyze the risk of MG development after adjusting for sex, age, and comorbidities, with hazard ratios and 95% confidence intervals. The incidence rates of MG in the non-M. pneumoniae and M. pneumoniae cohorts were 0.96 and 1.97 per 10,000 person-years, respectively. Another case–control study of patients with MG (n = 515) was conducted to analyze the impact of M. pneumoniae on MG occurrence as a sensitivity analysis. The analysis yielded consistent absence of a link between M. pneumoniae and MG. Although previous studies have reported that M. pneumoniae infection and MG may share associated immunologic pathways, we found no statistical significance between M. pneumoniae infection and subsequent development of MG in this study.

Irritable bowel syndrome and subsequent risk of Parkinson's disease: a nationwide population-based matched-cohort study.

Gastrointestinal dysfunction (GI) is the most prevalent non-motor symptom of Parkinson's disease (PD), and its role in the risk of PD has been studied. In this study, we tried to evaluate whether irritable bowel syndrome (IBS) increased the risk of PD development stratified by sex, age, and IBS duration using a large nationwide cohort in Korea. Patients aged ≥ 20years with a primary diagnosis of IBS (ICD-10 codes: G56) more than three times were selected. A randomly matched cohort without IBS was enrolled by exact matching patients for sex, age, socioeconomic status, comorbidities, and year of enrollment to the IBS group with a ratio of 1:3. Cause-specific Cox regression models were used to identify hazards associated with PD development depending on the presence of IBS during the 11-year follow-up period. In total, 285,064 patients were enrolled in the study: 71,806 in the IBS cohort and 213,258 in the comparison cohort. Cause-specific Cox regression model showed a hazard ratio of 1.436 (95% CI, 1.226-1.682) for PD development in the IBS cohort, which is consistent in both male and female sexes. Subgroup analyses according to age groups showed that IBS increased PD risk only in individuals ≥ 65years (HR = 1.449, 95% CI, 1.207-1.741). We found temporal relationship between IBS and PD at aged ≥ 65years. There might be a possibility that IBS was an early manifestation of PD, and future studies for causal link between the two diseases to elucidate biomechanism are warranted.

Increased risk of shoulder calcific tendinopathy in diabetes mellitus: A nationwide, population-based, matched cohort study.

Calcific tendinopathy of the rotator cuff is a common cause of painful disability in the shoulder with unclear aetiology. Diabetes mellitus (DM) is associated with calcific tendinopathy; however, large epidemiological data are lacking. Thus, we conducted a nationwide population-based matched cohort study to investigate the risk for calcific tendinopathy of the shoulder in diabetic patients. The National Health Insurance Research Database of Taiwan was used to include 42915 patients newly diagnosed with DM between 1 January 2000 and 31 December 2015 and randomly extract the data of 171660 individuals, as a matched control group. All individuals were followed-up until the development of calcific tendinopathy or the end of 2015. Overall, 122 patients from the DM group (0.284%) developed calcific tendinopathy compared with 340 individuals from the non-DM group (0.198%). The Kaplan-Meier analysis indicated that patients with DM had a higher risk of calcific tendinopathy since the eighth year of follow-up (log-rank test, P=.006). Cox proportional hazard regression revealed that the adjusted hazard ratio of calcific tendinopathy in diabetic patients to that in non-diabetic patients was 1.276 (95% confidence interval 1.037-1.571, P=.002). Moreover, the stratified analysis disclosed that DM was a strong independent risk factor for calcific tendinopathy irrespective of the existing comorbidities. This study demonstrated that patients with DM had a 27% increased risk of developing calcific tendinopathy of the shoulder, 8years after initially being diagnosed with DM.

Incidence of Psoriasis in Patients with Inflammatory Bowel Disease: A Nationwide Population-Based Matched Cohort Study

Background: Emerging data suggest that inflammatory bowel disease (IBD) and psoriasis are associated, sharing common genetic predispositions and immunological mechanisms. However, concrete data on psoriasis risk in IBD patients compared to the general population are limited. Objective: We investigated the risk of developing psoriasis in IBD patients compared to controls without IBD. Methods: Using the Korean National Health Insurance Database, patients diagnosed with Crohn’s disease (CD) or ulcerative colitis (UC) between 2005 and 2008 were age- and sex-matched 1:4 to non-IBD subjects from 2003 to 2018. IBD patients were defined by combining the International Classification of Diseases 10th revision code and at least one prescription of IBD-specific medications. Disease phenotypes, including psoriasis severity and psoriatic arthritis, were also identified. We investigated newly diagnosed psoriasis from 2009 to 2018. Incidence rates and risk of psoriasis were assessed with multivariate Cox regression models. Subgroup analyses for age and sex, and sensitivity analysis involving tumor necrosis factor (TNF) inhibitor-naïve patients were performed. Results: During nearly a decade of follow-up, 20,152 IBD patients were identified (14,619 [72.54%] UC and 5,533 [27.46%] CD). Among them, 439 patients were newly diagnosed with psoriasis (incidence rate of 217.68 per 100,000 person-years and 228.62 per 100,000 person-years for UC and CD, respectively). The psoriasis risk was higher in IBD patients than in the matched controls (adjusted hazard ratio, aHR, 2.95, 95% confidence interval, CI, 2.60–3.33). Moreover, IBD patients aged <30 years were at an increased risk (aHR 3.35, 95% CI 2.58–4.35), a trend that was unchanged across all psoriasis phenotypes. Sensitivity analysis of TNF inhibitor-naïve patients revealed consistent results. Conclusions: IBD patients were more likely to develop psoriasis compared to non-IBD subjects, including younger patients at an elevated risk regardless of TNF inhibitor use. This advocates the interplay between IBD and psoriasis; thus, inspection of cutaneous manifestation and dermatological consultation may be helpful in IBD patients at risk.

Effects of Hospice Care for Terminal Head and Neck Cancer Patients: A Nationwide Population-Based Matched Cohort Study

Background: Head and neck cancer was the fourth-most common cause of cancer death among Taiwanese men in 2018. Hospice care has been proven to reduce the use of invasive medical interventions and expenditures in caring for cancer patients. Aim: This study examined the effects of hospice care for terminal head and neck cancer patients. Design: A matched cohort study was used to compare the use of invasive interventions and expenditures among hospice care and nonhospice care patients. Setting/Participants: The investigated patients consisted of patients who died of head and neck cancer in Taiwan from 2004 to 2013 and were included in the Registry for Catastrophic Illness Patients in Taiwan and the Taiwan National Health Research Insurance Database. Results: A total of 45,948 terminal head and neck cancer patients were identified, and 9883 patients remained in each group after matching for comorbidities. After that matching, the rates of intensive care unit admission (23.9% vs. 38.94%, p < 0.0001), endotracheal intubation (10.05% vs. 31.32%, p < 0.0001), cardiopulmonary resuscitation (2.93% vs. 20.18%, p < 0.0001), defibrillation (0.51% vs. 4.36%. p < 0.0001), ventilator use (21.92% vs. 46.47%, p < 0.0001), blood transfusion (71.25% vs. 73.45%, p = 0.006), and hemodialysis (1.06% vs. 3.26%. p < 0.0001) were significantly lower in the hospice group than the nonhospice group, although the rates of parenteral nutrition for the two groups were similar (7.74% vs. 7.97%, p = 0.5432). The mean medical expenditure per person in the six months before death was 460,531 New Taiwan Dollar (NTD) for the nonhospice group and 389,079 NTD for those provided hospice care for more than three months, which was the lowest amount among various hospice enrollment durations. Conclusions: Hospice care can effectively reduce the use of invasive medical interventions in caring for terminal head and neck cancer patients and may improve their quality of death. Moreover, hospice care enrollment for more than three months can save on unnecessary medical expenditures for terminal head and neck cancer patients.

Increased risk of dementia in patients with nasopharyngeal cancer treated with radiation therapy: A nationwide population-based cohort study

PurposeWe evaluated the risk of dementia in patients with nasopharyngeal cancer (NPC) after undergoing radiation therapy (RT). MethodsBetween January 1, 2000, and December 31, 2015, 594 patients newly diagnosed with NPC and treated with RT (NPC cohort) were identified from the Longitudinal Health Insurance Database (LHID) for this nationwide population-based matched cohort study. LHID is a subset of the National Health Insurance Research Database of Taiwan. We selected 2376 controls (non-NPC comparison cohort) using a four-fold propensity score-matched by sex, age, comorbidities, education level, tobacco abuse, and index date (the date when the patient received first RT). After adjusting for confounding factors, Fine and Gray's competing risk analysis compared dementia development between the NPC study cohort and non-NPC comparison cohort over the observation period from 2000 to 2015. ResultsDementia development was 6.57% (39 of 594) and 4.42% (105 of 2376) in the NPC study cohort and non-NPC comparison cohort, respectively. Patients with NPC receiving RT were more likely to develop dementia than the comparison cohort, with a crude hazard ratio (HR) of 1.63 [95% confidence interval (CI) = 1.25–2.13, P < 0.001]. After adjusting for age, sex, education level, tobacco abuse, comorbidity, geographic area, urbanization level of the residence, and care level, the adjusted HR was 1.91 (95% CI = 1.42–2.51, P < 0.001). ConclusionsPatients with NPC receiving RT had a 1.91-fold higher risk of dementia than the non-NPC comparison controls.

The mortality rate of Parkinson's disease and related comorbidities: a nationwide population-based matched cohort study in Korea.

previous studies on mortality of Parkinson's disease (PD) enrolled a relatively small number of participants and were conducted in western countries. The objective of this study was to evaluate mortality rate of PD using a large nationwide cohort in Korea and to evaluate effects comorbidities have on mortality in PD. the nationwide population-based cohort study was conducted using the Korean National Health Insurance Service-National Sample Cohort data. Patients with a primary diagnosis of PD were selected from the database. A matched cohort without PD was enrolled through randomly matching patients by sex, age, year of diagnosis, residential area and income level to the PD group with a ratio of 1:9. The Cox proportional hazard model was used to assess mortality risk between the two cohorts. A logistic regression analysis was used to identify mortality risk factors in PD cohort. in total, 25,620 patients were enrolled. The Cox proportional regression model had an adjusted hazard ratio of 2.479 [95% confidence interval (CI), 2.272-2.704] for mortality in PD cohort. Comorbidities, such as ischaemic stroke [odds ratios (OR) = 2.314, 95% CI, 1.895-2.824], haemorrhagic stroke (OR = 2.281, 95% CI, 1.466-3.550) and chronic obstructive pulmonary disease (OR = 1.307, 95% CI, 1.048-1.630) were associated with increased mortality, whereas dyslipidemia (OR = 0.285, 95% CI, 0.227-0.358) was negatively correlated with mortality. over the 10year follow-up period, the PD cohort's mortality rate was 2.5 times higher than the comparison cohort. Understanding the effects that comorbidities have on morality in PD would be useful for predicting mortality in patients with PD.

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.

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.

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.

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.

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.

Incidence and Risk of Carpal Tunnel Syndrome in End-Stage Renal Disease Patients on Dialysis: A Nationwide Population-Based Matched Cohort Study.

Carpal tunnel syndrome (CTS) is a common cause of compression neuropathy of the upper extremities. This retrospective nationwide matched cohort study was conducted using the data from the Taiwan National Health Insurance Research Database between January 2003 and December 2012. The incidence rate of CTS was 975.84 and 544.12/100,000 person-years, respectively, yielding an incidence rate ratio of 1.79 (95% confidence interval, 1.68-1.91, P < 0.0001). CTS patients with End-stage renal disease (ESRD) in the dialysis group were more likely to receive surgical intervention than those the control group (62.41% vs 12.89%, P < 0.0001). The risk of CTS was significantly higher in the ESRD on dialysis cohort (10-year cumulative incidence, 8.0%) than in the control cohort (5.1%), which yielded an adjusted hazard ratio of 13.95 (95% confidence interval, 10.95-17.76, P < 0.0001). The high risk of CTS in ESRD patients on dialysis suggests that timely referral to hand surgeons with appropriate treatment should prevent permanent median nerve damage by CTS and may possibly improve patients' quality of life.

Long-term Mortality and Epilepsy in Patients After Brain Abscess: A Nationwide Population-Based Matched Cohort Study.

We aimed to determine the long-term risks of mortality and new-onset epilepsy after brain abscess. Using nationwide population-based medical registries, we examined all patients with first-time brain abscess in Denmark, 1982-2016. Comparison cohorts individually matched on age, sex, and residence were identified, as were siblings of all study participants. Next, we computed cumulative incidences and hazard rate ratios (HRRs) with 95% confidence intervals of mortality and new-onset epilepsy among study populations. We identified 1384 brain abscess patients (37% females) with a median follow-up time of 5.9 years (interquartile range [IQR] 1.1-14.2). The 1-year, 2-5 year, and 6-30 year mortality of patients after brain abscess was 21%, 16%, and 27% as compared to 1%, 6%, and 20% for population controls. Cox regression analyses adjusted for Charlson comorbidity index score showed 1-year, 2-5 year, and 6-30 year HRRs of 17.5 (13.9-22.0), 2.61 (2.16-3.16), and 1.94 (1.62-2.31). The mortality in brain abscess patients was significantly increased regardless of sex or age group except among subjects 80 years or older, and in both previously healthy individuals and immunocompromised persons.Among the 30-day survivors of brain abscess (median follow-up 7.6 years [IQR 2.2-15.5]), new-onset epilepsy occurred in 32% compared to 2% in matched population controls. Cause-specific Cox regression analysis adjusted for stroke, head trauma, alcohol abuse, and cancer showed 1-year, 2-5 year, and 6-30 year HRRs for new-onset epilepsy of 155 (78.8-304), 37.7 (23.0-59.9), and 8.93 (5.62-14.2). Brain abscess is associated with an increased long-term risk of mortality and new-onset epilepsy for several years after infection.

1402. Long-Term Mortality and Epilepsy in Patients After Brain Abscess: A Nationwide Population-based Matched Cohort Study

BackgroundThe long-term outcome of brain abscess is unclear.MethodsWe used medical registries to conduct a nationwide population-based matched cohort study to examine the long-term risks of mortality and new-onset epilepsy in patients hospitalized with brain abscess in Denmark from 1982 through 2016. Comparison cohorts from the same population individually matched on age, sex, and residence were identified, as were siblings of all study participants (Figure 1). We computed cumulative incidences and hazard rate ratios (HRRs) for mortality and new-onset epilepsy among brain abscess patients, comparison cohorts and siblings. Population and appendicitis controls had similar characteristics and prognosis why only comparisons between brain abscess patients and population controls are detailed here.ResultsWe identified 1,384 brain abscess patients with a median follow-up time of 5.9 years (IQR 1.1–14.2). The 1-year, 2–5 year, and 6–30-year mortality of patients after brain abscess was 21%, 16% and 27% when compared with 1%, 6% and 20% for matched population controls (Figure 2). Cox regression analyses adjusted for Charlson comorbidity index score showed 1-year, 2–5 year, and 6- to 30-year HRRs of 17.5 (95% CI 13.9–22.2), 2.61 (95% CI 2.16–3.16) and 1.94 (95% CI 1.62–2.31). The mortality in brain abscess patients compared with population controls was significantly increased regardless of sex or age group except among subjects 80 years or older, and in both previously healthy individuals and immuno-compromised persons. Among the 30-day survivors of brain abscess (median follow-up 7.6 years [IQR 2.2–15.5]), new-onset epilepsy occurred in 32% compared with 2% in matched population controls. Cause-specific Cox regression analysis adjusted for stroke, head trauma, alcohol abuse, and cancer showed 1-year, 2–5-year, and 6–30-year HRRs for new-onset epilepsy of 155 (95% CI 78.8–304), 37.7 (95% CI 23.0–59.9), and 8.93 (95% CI 5.62–14.2) (Figure 3). Comparisons between sibling cohorts suggested no substantial effect of family-related factors on the long-term risk of death or epilepsy after brain abscess (Figure 4).ConclusionBrain abscess is associated with an increased long-term risk of mortality and new-onset epilepsy for several years after the acute infection. Disclosures All authors: No reported disclosures.

Increased risk of diabetes mellitus five years after an episode of Staphylococcus aureus bacteraemia

Background: Diabetes mellitus is a risk factor for infection with Staphylococcus aureus, but it is unclear whether S. aureus infection is a prediabetic condition.Methods: Nationwide population-based matched cohort study. Incidence rate and ratio with 95% confidence interval of diabetes were estimated by negative binomial regression.Results: Of 19,988 individuals with S. aureus bacteraemia and 185,579 population comparators, 667 and 4974 had a primary diagnose of diabetes within five years after discharge of S. aureus bacteraemia corresponding to a more than double risk of diabetes (adjusted incidence rate ratio 2.28 (95% confidence interval: 2.10–2.46)). Other factors associated with an increased risk of diabetes during follow-up were male sex, increasing age and level of comorbidity. Of the S. aureus bacteraemia and population cohort, 422 (2.11%) and 4048 (2.18%), respectively, developed diabetes without complications, while 245 (1.23%) and 926 (0.50%), respectively, developed diabetes with complications. Rates of diabetes without complication were increased for individuals in the S. aureus bacteraemia cohort compared to the population cohort within the first two years after which rates were comparable while rates of diabetes with complications remained higher throughout the five year follow-up period compared to the population cohort.Conclusions: The risk of diabetes was markedly increased up to five years after S. aureus bacteraemia compared to a population cohort. In addition to screening for diabetes during hospital admittance, screening cases of S. aureus bacteraemia for diabetes in the years following S. aureus bacteraemia may allow for earlier detection of diabetes.

Menopausal hormone therapy and biliary tract cancer: a population-based matched cohort study in Sweden

Background: This study tested the hypothesis that contemporary menopausal hormonal therapy (MHT) increases the risk of biliary tract cancer. The risk of cancer of the biliary tract (gallbladder and extra-hepatic bile ducts) may be increased following estrogen exposure.Material and methods: This was a nationwide population-based matched cohort study in Sweden. Data from the Swedish Prescribed Drug Register identified all women exposed to systemic MHT in 2005–2012. Group-level matching (1:3 ratio) was used to select women unexposed to MHT from the same study base, matched for history of delivery, thrombotic events, hysterectomy, age, smoking- and alcohol related diseases, obesity, and diabetes. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI).Results: Comparing 290,186 women exposed to MHT with 870,165 unexposed, MHT did not increase the OR of biliary tract cancer. The OR of gallbladder cancer was rather decreased in MHT users (OR 0.58, 95% CI 0.43–0.79), but this association became attenuated and statistically non-significant after adjusting for gallstone disease (OR 0.84, 95% CI 0.60–1.15). The OR of extra-hepatic bile duct cancers was 0.83 (95% CI 0.61–1.15). There were no clear differences when the analyses were stratified for estrogen or estrogen/progestogen combinations. MHT increased the risk of gallstone disease (OR 6.95, 95% CI 6.64–7.28).Conclusions: Contemporary MHT does not seem to increase the risk of biliary tract cancer. The decreased risk of gallbladder cancer may be explained by the increased use of surgery for symptomatic gallstones in MHT users.

Utilisation of primary care before a childhood cancer diagnosis: do socioeconomic factors matter?: A Danish nationwide population-based matched cohort study

ObjectivesEarly diagnosis of childhood cancer is critical. Nevertheless, little is known about the potential role of inequality. This study aims to describe the use of primary care 2 years before...