Gastroesophageal Reflux Disease and Atrial Fibrillation: A Nationwide Population-Based Study

Objectives

Precise mechanisms of atrial fibrillation (AF) are uncertain, but their association with esophageal disorders has been recently proposed. The association between gastroesophageal reflux disease (GERD), the most common gastroesophageal disorder, and AF remains undetermined. We therefore aimed to investigate the association between GERD and later development of AF.

Methods and Results

Patients with GERD were identified from the 1,000,000-person cohort dataset sampled from the Taiwan National Health Insurance database. The study cohort comprised 29,688 newly diagnosed adult GERD patients; 29,597 randomly selected age-, gender-, comobidity-matched subjects comprised the comparison cohort. Cox proportional hazard regressions were performed as a means of comparing the AF-free survival rate for the two cohorts. During a maximum three years of follow-up, a total of 351 patients experienced AF, including 184 (0.62%) patients in the GERD cohort and 167 (0.56%) in the control group. The log-rank test showed that patients with GERD had significantly higher incidence of AF than those without GERD (p = 0.024). After Cox proportional hazard regression model analysis, GERD was independently associated with the increased risk of AF (hazard ratio, 1.31; 95% confidence interval, 1.06–1.61, p = 0.013).

Conclusion

GERD was independently associated with an increased risk of future AF in a nationwide population-based cohort.     

Rheumatoid Arthritis and the Risk of Bipolar Disorder: A Nationwide Population-Based Study

Background

Studies have suggested that chronic inflammation plays an essential role in the pathophysiology of both rheumatoid arthritis (RA) and bipolar disorder. The most common clinical features associated with RA are anxiety and depression. The risk of bipolar disorder among patients with RA has not been characterized adequately.

Objective

To determine the association between RA and the subsequent development of bipolar disorder and examine the risk factors for bipolar disorder among patients with RA.

Methods

We identified patients who were diagnosed with RA in the Taiwan National Health Insurance Research Database. A comparison cohort was created by matching patients without RA with those with RA according to age, sex, and comorbidities. The occurrence of bipolar disorder was evaluated in both cohorts.

Results

The RA cohort consisted of 2,570 patients, and the comparison cohort consisted of 2,570 matched control patients without RA. The incidence of bipolar disorder (incidence rate ratio  = 2.13, 95% confidence interval [CI]  = 1.12–4.24, P =  .013) was higher among patients with RA than among control patients. Multivariate, matched regression models revealed that asthma (hazard ratio [HR]  = 2.76, 95% CI 1.27–5.96, P =  .010), liver cirrhosis (HR  = 3.81, 95% CI  = 1.04–14.02, P =  .044), and alcohol use disorders (HR  = 5.29, 95% CI  = 1.71–16.37, P =  .004) were independent risk factors for the development of bipolar disorder among patients with RA.

Conclusion

RA might increase the incidence of bipolar disorder development. Based on our data, we suggest that, following RA diagnosis, greater attention be focused on women with asthma, liver cirrhosis, and alcohol use disorder. Prospective clinical studies of the relationship between RA and bipolar disorder are warranted.     

Hyperthyroidism and Risk for Bipolar Disorders: A Nationwide Population-Based Study

Background

Thyroid disorders have long been associated with psychiatric illness, often with symptoms suggestive of mood disorders. The most common clinical features associated with hyperthyroidism are anxiety and depression. The risk of bipolar disorders, especially bipolar mania, among patients with thyroid disorders has not been well characterized.

Objective

We explored the relationship of hyperthyroidism and the subsequent development of bipolar disorders, and examined the risk factors for bipolar disorders in patients with hyperthyroidism.

Methods

We identified patients who were diagnosed with hyperthyroidism between 2000 and 2010 in the Taiwan National Health Insurance Research Database. A comparison cohort without hyperthyroidism was matched based on age, sex, and comorbidities. The occurrence of bipolar disorders was evaluated in both cohorts based on diagnosis and the use of mood stabilizer drugs.

Results

The hyperthyroidism cohort consisted of 21, 574 patients, and the comparison cohort consisted of 21, 574 matched control patients without hyperthyroidism. The incidence of bipolar disorders (incidence rate ratio [IRR], 2.31, 95% CI 1.80–2.99, P<.001) was higher for the hyperthyroidism patients than the control patients. Multivariate, matched regression models showed that women (HR 2.02, 95% CI 1.34–3.05, P = .001), patients with alcohol use disorders (HR 3.03, 95% CI 1.58–5.79, P = .001), and those with asthma (HR 1.70, 95% CI 1.18–2.43, P = .004) were independent risk factors for the development of bipolar disorders in hyperthyroidism patients.

Conclusions

Although a possibility that the diagnosis of bipolar disorders in this study actually includes "bipolar disorders due to hyperthyroidism" cannot be excluded, this study suggests that hyperthyroidism may increase the risk of developing bipolar disorders.     

The Risk of Cancer in Patients with Generalized Anxiety Disorder: A Nationwide Population-Based Study

Objective

To evaluate the risk of cancer among patients with generalized anxiety disorder (GAD) in a nationwide population-based dataset.

Methods

We recruited newly-diagnosed GAD patients aged 20 years or older without antecedent cancer from the Taiwan National Health Insurance Research database between 2000–2010. Standardized incidence ratios (SIRs) of cancers were calculated in GAD patients, and the subgroup of GAD patients diagnosed by psychiatric specialists.

Results

A total of 559 cancers developed among 19,793 GAD patients with a follow-up of 89,485 person-years (median follow-up of 4.34 years), leading to a significantly increased SIR of 1.14 [95% confidence interval (CI) 1.05–1.24]. Male GAD patients had a significantly increased SIR overall (1.30, 95% CI 1.15–1.46) and for lung and prostate cancer (1.77, 95% CI 1.33–2.30 and 2.17, 95% CI 1.56–2.93, respectively). Patients over 80 years of age also had a significantly increased SIR (1.56, 95% CI 1.25–1.92), especially in males. However, psychiatrist-diagnosed GAD patients did not show increased cancer risk relative to the general population, perhaps due to having fewer physical comorbidities than non-psychiatrist-diagnosed GAD patients.

Conclusion

This study found that overall cancer risk is elevated among patients with GAD. The risk of lung and prostate cancer also increased in male patients with GAD. This increased cancer risk may be due to physical comorbidities and surveillance bias. Further prospective study is necessary to confirm these findings.     

Erectile Dysfunction and Risk of End Stage Renal Disease Requiring Dialysis: A Nationwide Population-Based Study

Background

Previous studies have suggested that erectile dysfunction (ED) is an independent risk factor for macrovascular disease. Very few studies have evaluated the relationship between ED and risk of end stage renal disease (ESRD) requiring dialysis.

Methods

A random sample of 1,000,000 individuals from Taiwan''s National Health Insurance database was collected. We selected the control group by matching the subjects and controls by age, diabetes, hypertension, coronary heart disease, hyperlipidemia, area of residence, monthly income and index date. We identified 3985 patients with newly-diagnosed ED between 2000 and 2008 and compared them with a matched cohort of 23910 patients without ED. All patients were tracked from the index date to identify which patients subsequently developed a need for dialysis.

Results

The incidence rates of dialysis in the ED cohort and comparison groups were 10.85 and 9.06 per 10000 person-years, respectively. Stratified by age, the incidence rate ratio for dialysis was greater in ED patients aged <50 years (3.16, 95% CI: 1.62–6.19, p = 0.0008) but not in aged 50–64 (0.94, 95% CI: 0.52–1.69, p = 0.8397) and those aged ≧65 (0.69, 95% CI: 0.32–1.52, p = 0.3594). After adjustment for patient characteristics and medial comorbidities, the adjusted HR for dialysis remained greater in ED patients aged <50 years (adjusted HR: 2.08, 95% CI: 1.05–4.11, p<0.05). The log-rank test revealed that ED patients <50-years-old had significantly higher cumulative incidence rates of dialysis than those without (p = 0.0004).

Conclusion

Patients with ED, especially younger patients, are at an increased risk for ESRD requiring dialysis later in life.     

Risk of End-Stage Renal Disease after Cancer Nephrectomy in Taiwan: A Nationwide Population-Based Study

BackgroundThe conclusions of population-based studies examining the risk of developing end-stage renal disease (ESRD) after nephrectomy among patients with renal cell carcinoma (RCC) remain inconclusive. In this study, we sought to examine whether patients with RCC undergoing radical nephrectomy (RN) have higher risk of ESRD compared to those undergoing partial nephrectomy (PN).MethodsNationwide population-based retrospective cohort of 7670 patients with RCC who underwent RN or PN between 2000 and 2011 as recorded in the Taiwan National Health Insurance in-patient claims data were analyzed. The primary outcome of interest was the occurrence of ESRD requiring regular renal hemodialysis. Multivariable Cox proportional hazard regression model was performed to assess the risk.FindingsThe median follow-up for the post-propensity matched cohort (1212 PN and 2424 RN) was 48 months. Seventy patients (2.9%) developed ESRD among those who underwent RN, for an incidence rate of 6.9 cases per 1000 person-years. In contrast, only 23 patients (1.9%) developed ESRD among patients who underwent PN, for an incidence rate of 5.5 cases per 1000 person-years. Despite the higher incidence rate of ESRD among RN, the aIRR (RN/PN) was 1.26 (95% CI 0.78-2.01), which was not statistically significant.ConclusionsThis Taiwan nationwide population-based study suggests that patients with RCC undergoing RN do not have significantly higher risk of developing ESRD compared to those undergoing PN.     

Relative Risk of Acute Myocardial Infarction in People with Schizophrenia and Bipolar Disorder: A Population-Based Cohort Study

Objective

Despite high mortality associated with serious mental illness, risk of acute myocardial infarction (AMI) remains unclear, especially for patients with bipolar disorder. The main objective was to investigate the relative risk of AMI associated with schizophrenia and bipolar disorders in a national sample.

Method

Using nationwide administrative data, an 11-year historic cohort study was assembled, comprised of cases aged 18 and above who had received a diagnosis of schizophrenia or bipolar disorder, compared to a random sample of all other adults excluding those with diagnoses of serious mental illness. Incident AMI as a primary diagnosis was ascertained. Hazard ratios stratified by age and gender were calculated and Cox regression models were used to adjust for other covariates.

Results

A total of 70,225 people with schizophrenia or bipolar disorder and 207,592 people without serious mental illness were compared. Hazard ratios in men adjusted for age, income and urbanization were 1.15 (95% CI 1.01~1.32) for schizophrenia and 1.37 (1.08~1.73)for bipolar disorder, and in women, 1.85 (1.58~2.18) and 1.88(1.47~2.41) respectively. Further adjustment for treated hypertension, diabetes and hyperlipidaemia attenuated the hazard ratio for men with schizophrenia but not the other comparison groups. Hazard ratios were significantly stronger in women than men and were stronger in younger compared to older age groups for both disorders; however, gender modification was only significant in people with schizophrenia, and age modification only significant in people with bipolar disorder.

Conclusions

In this large national sample, schizophrenia and bipolar disorder were associated with raised risk of AMI in women and in the younger age groups although showed differences in potential confounding and modifying factors.     

Helicobacter pylori and Gastroesophageal Reflux Disease: A Case–Control Study

Background:  Gastric colonization with Helicobacter pylori is a proposed protective factor against gastroesophageal reflux disease (GERD), but little population-based data exist and other data conflict.
Methods:  We conducted a case–control study within the membership of a large integrated health-care system that compared GERD-free subjects with two groups: subjects with a physician-assigned GERD diagnosis and randomly selected members with self-described weekly GERD symptoms. Subjects completed interviews, GERD questionnaires, and antibody testing for H. pylori and its cagA protein.
Results:  Serologic data were available for 301 physician-assigned GERD patients, 81 general membership subjects with GERD symptoms, and 175 general membership subjects without GERD symptoms. Physician-assigned GERD patients were less likely to have H. pylori antibodies than GERD-free member controls (odds ratio (OR) = 0.27, 95% confidence interval (CI) 0.15–0.47); there was also an inverse association between H. pylori and GERD symptom severity (OR = 0.18, 95% CI 0.08–0.41; severe or very severe symptoms) and GERD frequency (OR = 0.18, 95% CI 0.09–0.38; for symptoms at least weekly). The association was stronger among persons with erosive GERD and was similar between H. pylori -positive subjects with and without cagA. There was no association among persons who were cagA positive, but H. pylori negative. Similar findings were found in analyses of the general membership with self-described GERD symptoms.
Conclusions:  H. pylori antibody status was inversely associated with a GERD diagnosis and GERD symptoms compared with a general membership population.     

Peptic Ulcer Disease in Healthcare Workers: A Nationwide Population-Based Cohort Study

Health care workers (HCWs) in Taiwan have heavy, stressful workloads, are on-call, and have rotating nightshifts, all of which might contribute to peptic ulcer disease (PUD). We wanted to evaluate the PUD risk in HCWs, which is not clear. Using Taiwan’s National Health Insurance Research Database, we identified 50,226 physicians, 122,357 nurses, 20,677 pharmacists, and 25,059 other HCWs (dieticians, technicians, rehabilitation therapists, and social workers) as the study cohort, and randomly selected an identical number of non-HCW patients (i.e., general population) as the comparison cohort. Conditional logistical regression analysis was used to compare the PUD risk between them. Subgroup analysis for physician specialties was also done. Nurses and other HCWs had a significantly higher PUD risk than did the general population (odds ratio [OR]: 1.477; 95% confidence interval [CI]: 1.433–1.521 and OR: 1.328; 95% CI: 1.245–1.418, respectively); pharmacists had a lower risk (OR: 0.884; 95% CI: 0.828–0.945); physicians had a nonsignificantly different risk (OR: 1.029; 95% CI: 0.987–1.072). In the physician specialty subgroup analysis, internal medicine, surgery, Ob/Gyn, and family medicine specialists had a higher PUD risk than other physicians (OR: 1.579; 95% CI: 1.441–1.731, OR: 1.734; 95% CI: 1.565–1.922, OR: 1.336; 95% CI: 1.151–1.550, and OR: 1.615; 95% CI: 1.425–1.831, respectively). In contrast, emergency physicians had a lower risk (OR: 0.544; 95% CI: 0.359–0.822). Heavy workloads, long working hours, workplace stress, rotating nightshifts, and coping skills may explain our epidemiological findings of higher risks for PUD in some HCWs, which might help us improve our health policies for HCWs.     

Type 2 Diabetes : An Independent Risk Factor for Tuberculosis: A Nationwide Population-Based Study

Objective

Tuberculosis continues to be a major global health problem. We wanted to investigate whether Type 2 diabetes was a risk factor for tuberculosis in an Asian population.

Methods

From Taiwan’s National Health Insurance Research Database, we collected data from 31,237 female patients with type 2 diabetes and 92,642 female controls and 32,493 male patients with type 2 diabetes and 96,977 male controls. Cox proportional hazard regression was performed to evaluate independent risk factors for tuberculosis in all patients and to identify risk factors in patients with type 2 diabetes.

Results

During the study period, both female (standardized incidence ratio (SIR): 1.40, p<0.01) and male (SIR: 1.48, p<0.01) patients with type 2 diabetes were found to have a significantly higher rate of incident tuberculosis than the control group. Type 2 diabetes (HR:1.31, 1.23–1.39, p<0.001) was significantly associated with tuberculosis after adjusting sex, age, bronchiectasis, asthma and chronic obstructive lung disease.

Conclusions

Patients with type 2 diabetes have a higher risk of tuberculosis compared to control subjects after adjusting for confounding factors. The current diabetes epidemic may lead to a resurgence of tuberculosis in endemic regions. Therefore, preventive measures, including addressing the possibility that type 2 diabetes increase the individual’s susceptibility for incident TB, should be taken to further reduce the incidence of tuberculosis.     

Increased Risk of Acute Coronary Syndrome among Patients with Urinary Stone Disease: A Nationwide Population-Based Cohort Study

Background/Objectives

Urinary stones (US) are associated with systemic metabolic and endocrine disorders that share risk factors typically associated with acute coronary syndrome (ACS).

Methods

For this investigation, 30 142 patients with US were set as the research group, and 121 768 randomly selected patients were set as the comparison group through frequency matching by age, sex, and index year. Each patient was individually tracked to identify those who developed ACS during the follow-up period. Cox proportional hazards regression and the Kaplan-Meier method were adopted to calculate the hazard ratios of ACS risk and plot the survival curve.

Results

Overall, 275 (13.4 per 10 000 person-y) and 736 events (9.1 per 10 000 person-y) were observed among patients in the research and comparison cohorts, respectively. The patients with US had a substantially lower ACS-free survival rate compared with that of the patients in the comparison cohort (P<.001). After adjusting for potential risk factors, the patients with US were observed to have a 1.22-fold higher risk of ACS compared with patients in the comparison cohort (95% confidence interval = 1.05–1.40, P<.001), particularly among younger patients.

Conclusions

The results indicate that US is associated with increased risk of developing ACS, particularly among young (≤49 years) and male adults. Future studies should examine the possible mechanisms of US-related ACS morbidity by conducting multicenter recruitment and measurements of laboratory data.     

Risk of Developing Depressive Disorders following Rheumatoid Arthritis: A Nationwide Population-Based Study

Background & Aims

To evaluate the risk of depressive disorders among rheumatoid arthritis (RA) by using the Taiwan National Health Insurance Research Database (NHIRD).

Methods

We conducted a retrospective study of a matched cohort of 18 285 participants (3 657 RA patients and 14 628 control patients) who were selected from the NHIRD. Patients were observed for a maximum of 10 years to determine the rates of newly diagnosed depressive disorders, and Cox regression was used to identify the risk factors associated with depressive disorders in RA patients.

Results

During the 10-year follow-up period, 205 (11.2 per 1000 person-years) RA patients and 384 (5.1 per 1000 person-years) control patients were diagnosed with depressive disorders. In RA patients, most depressive disorders (n = 163, 80%) developed with five years of being diagnosed with RA. The incidence risk ratio of depressive disorders between RA patients and control patients was 2.20 (95% confidence interval [CI], 1.84–2.61, P<.001). After adjusting for age, sex, and comorbidities, RA patients were 2.06 times more likely to develop depressive disorders (95% CI, 1.73–2.44, P<.001) compared with the control patients. Hyperthyroidism (HR = 1.67) was an independent risk factor for depressive disorders in patients with RA.

Conclusions

The likelihood of developing depressive disorders is greater among RA patients than among patients without RA. Symptoms of depression should be sought in patients with RA.     

Risk of Developing Depressive Disorders following Hepatocellular Carcinoma: A Nationwide Population-Based Study

Background & Aims

To evaluate the risk of depressive disorders among patients with Hepatocellular Carcinoma (HCC) using the National Health Insurance Research Database (NHIRD) in Taiwan.

Methods

We conducted a retrospective study of a newly diagnosed HCC cohort of 55,973 participants who were selected from the NHIRD. Patients were observed for a maximum of 6 years to determine the rates of newly onset depressive disorders, and Cox regression was used to identify the risk factors associated with depressive disorders in HCC patients.

Results

Of the total 55,973 HCC patients, 1,041 patients (1.86%) were diagnosed with depressive disorders during a mean (SD) follow-up period of 1.1 (1.2) years. The Cox multivariate proportional hazards analysis showed that age of 40–59 (HR 1.376, 95% CI 1.049–1.805, p = 0.021), age of 60–79 (HR 1.341, 95% CI 1.025–1.753, p = 0.032), women (HR 1.474 95% CI 1.301–1.669, p < 0.001), metastasis (HR 1.916, 95% CI 1.243–2.953, p = 0.003), and HCV (HR 1.445, 95% CI 1.231–1.697, p < 0.001) were independent risk factors for developing depressive disorders.

Conclusions

Our study indicated a subsequent risk of depressive disorders in patients with HCC, and the risk increased for those with female gender, aged 40 to 59, aged 60 to 79, with metastasis, or with HCV. Psychological evaluation and support are two critical issues in these HCC patients with the risk factors.     

Risk of Cancer in Patients with Iron Deficiency Anemia: A Nationwide Population-Based Study

ObjectiveThis study evaluated the risk of cancer among patients with iron deficiency anemia (IDA) by using a nationwide population-based data set.MethodPatients newly diagnosed with IDA and without antecedent cancer between 2000 and 2010 were recruited from the Taiwan National Health Insurance Research Database. The standardized incidence ratios (SIRs) of cancer types among patients with IDA were calculated.ResultsPatients with IDA exhibited an increased overall cancer risk (SIR: 2.15). Subgroup analysis showed that patients of both sexes and in all age groups had an increased SIR. After we excluded patients diagnosed with cancer within the first and first 5 years of IDA diagnosis, the SIRs remained significantly elevated at 1.43 and 1.30, respectively. In addition, the risks of pancreatic (SIR: 2.31), kidney (SIR: 2.23), liver (SIR: 1.94), and bladder cancers (SIR: 1.74) remained significantly increased after exclusion of patients diagnosed with cancer within 5 years after IDA diagnosis.ConclusionThe overall cancer risk was significantly elevated among patients with IDA. After we excluded patients diagnosed with IDA and cancer within 1 and 5 years, the SIRs remained significantly elevated compared with those of the general population. The increased risk of cancer was not confined to gastrointestinal cancer when the SIRs of pancreatic, kidney, liver, and bladder cancers significantly increased after exclusion of patients diagnosed with IDA and cancer within the first 5 years. This finding may be caused by immune activities altered by IDA. Further study is necessary to determine the association between IDA and cancer risk.     

Risk of Psychiatric Disorders following Polycystic Ovary Syndrome: A Nationwide Population-Based Cohort Study

Background

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders among women of reproductive age. A higher prevalence of psychiatric comorbidities, including depressive disorder, anxiety disorder, and bipolar disorder has been proved in patients with PCOS. However, a clear temporal causal relationship between PCOS and psychiatric disorders has not been well established.

Objective

We explored the relationship between PCOS and the subsequent development of psychiatric disorders including schizophrenia, bipolar disorder, depressive disorder, anxiety disorder, and sleep disorder.

Methods

We identified patients who were diagnosed with PCOS by an obstetrician-gynecologist in the Taiwan National Health Insurance Research Database. A comparison cohort was constructed of patients without PCOS who were matched according to age and sex. The occurrence of subsequent new-onset psychiatric disorders was evaluated in both cohorts based on diagnoses made by psychiatrists.

Results

The PCOS cohort consisted of 5431 patients, and the comparison cohort consisted of 21,724 matched control patients without PCOS. The incidence of depressive disorder (hazard ratio [HR] 1.296, 95% confidence interval [CI] 1.084–.550), anxiety disorder (HR 1.392, 95% CI 1.121–1.729), and sleep disorder (HR 1.495, 95% CI 1.176–1.899) were higher among the PCOS patients than among the patients in the comparison cohort. In addition, a higher incidence of newly diagnosed depressive disorder, anxiety disorder, and sleep disorder remained significantly increased in all of the stratified follow-up durations (0–1, 1–5, ≥5 y).

Conclusions

PCOS might increase the risk of subsequent newly diagnosed depressive disorder, anxiety disorder, and sleep disorder. The risk of newly diagnosed bipolar disorder, which has often been reported in the literature to be comorbid with PCOS, was not significantly elevated.     

Rheumatoid Arthritis Risk Associated with Periodontitis Exposure: A Nationwide,Population-Based Cohort Study

Background

The risk of periodontitis (PD) is increased in the patient group of rheumatoid arthritis (RA). RA and PD also shared some pathological mechanism. The aim of this study is to investigate the risk of RA associated with PD exposure.

Methods and Findings

This study identified 3 mutually exclusive cohorts using the 1999–2010 Taiwanese National Health Insurance Research Database (NHIRD) to investigate the association between PD and the risk of incident RA. All patients with PD in 2000 were identified from the database of all enrollees as the PD cohort. From the representative database of 1,000,000 enrollees randomly selected in 2010 (LHID2010), individuals without any periodontal disease (PO) during 1999–2010 were selected as the non-PO cohort. Individuals who were not included in the non-PO cohort and received dental scaling (DS) no more than two times per year during 1999–2010 were selected as the DS cohort from LHID2010. Using cox proportional regression analysis, hazard ratios (HRs) with 95% confidence intervals (Cis) were calculated to quantify the association between PD exposure and RA development. In the three-group comparison using the non-PO cohort as reference, we found that the risk of RA was higher in the PD and DS cohorts (HRs, 1.89 and 1.43; 95% CIs, 1.56–2.29 and 1.09–1.87, respectively). For comparisons between two cohorts, the PD cohort had a higher risk of RA than the non-PO and DS cohorts (HRs, 1.91 and 1.35; 95% CIs, 1.57–2.30 and 1.09–1.67, respectively).

Conclusion

PD was associated with an increased risk of RA development.     

Increased Risk of Active Tuberculosis following Acute Kidney Injury: A Nationwide,Population-Based Study

Background

Profound alterations in immune responses associated with uremia and exacerbated by dialysis increase the risk of active tuberculosis (TB). Evidence of the long-term risk and outcome of active TB after acute kidney injury (AKI) is limited.

Methods

This population-based-cohort study used claim records retrieved from the Taiwan National Health Insurance database. We retrieved records of all hospitalized patients, more than 18 years, who underwent dialysis for acute kidney injury (AKI) during 1999–2008 and validated using the NSARF data. Time-dependent Cox proportional hazards model to adjust for the ongoing effect of end-stage renal disease (ESRD) was conducted to predict long-term de novo active TB after discharge from index hospitalization.

Results

Out of 2,909 AKI dialysis patients surviving 90 days after index discharge, 686 did not require dialysis after hospital discharge. The control group included 11,636 hospital patients without AKI, dialysis, or history of TB. The relative risk of active TB in AKI dialysis patients, relative to the general population, after a mean follow-up period of 3.6 years was 7.71. Patients who did (hazard ratio [HR], 3.84; p<0.001) and did not (HR, 6.39; p<0.001) recover from AKI requiring dialysis had significantly higher incidence of TB than patients without AKI. The external validated data also showed nonrecovery subgroup (HR = 4.37; p = 0.049) had high risk of developing active TB compared with non-AKI. Additionally, active TB was associated with long-term all-cause mortality after AKI requiring dialysis (HR, 1.34; p = 0.032).

Conclusions

AKI requiring dialysis seems to independently increase the long-term risk of active TB, even among those who weaned from dialysis at discharge. These results raise concerns that the increasing global burden of AKI will in turn increase the incidence of active TB.     

Retinitis Pigmentosa Reduces the Risk of Proliferative Diabetic Retinopathy: A Nationwide Population-Based Cohort Study

Purpose

To study the association between retinitis pigmentosa (RP) and the progression of diabetic retinopathy (DR).

Methods

Using the Longitudinal Health Insurance Database 2000 of Taiwan, we identified individuals with an initial diagnosis for RP during the period of 1997–2008. A non-RP comparison group, 10-fold frequency matched by sex, age, index year and the year of diabetes diagnosed, were randomly selected from the same database. The occurrence of DR was observed for all subjects until the end of 2009. The Kaplan-Meier curves were used to illustrate the cumulative probability of developing DR for the RP group and comparison groups. The hazard ratio (HR) of DR for the RP group relative to the comparison group was estimated using Cox proportional hazards model after adjusting for potential confounders.

Results

The Kaplan-Meier curves were not statistically significant different between the RP group and the comparison group. However, the RP group had a higher cumulative probability of developing DR during the first six to seven years. The cumulative probability kept increasing and became higher in the comparison group but remained unchanged in the RP group. The HR for the RP patients comparing with the comparison group was 0.96 (95% confidence interval (CI) = 0.43–2.14). Stratified by severity, RP was associated with a non-statistically significant reduced risk of proliferative DR (PDR) (HR = 0.70, 95% CI = 0.16–3.14). The HR for non-proliferative DR (NPDR) was 1.08 (95% CI = 0.40–2.86).

Conclusion

In this study, RP was not statistically significant associated with the incidence of DR.