Risk of Second Primary Cancer among Prostate Cancer Patients in Korea: A Population-Based Cohort Study

As patients with prostate cancer have a long life expectancy, there is increasing interest in predicting the risk of development of a second primary cancer (SPC), and we therefore designed this study to estimate the overall risk of developing SPCs among Korean prostate cancer patients. We used a population-based cohort from the Korean Central Cancer Registry composed of 55,378 men diagnosed with a first primary prostate cancer between 1993 and 2011. Standardized incidence ratios (SIRs) of SPCs were analyzed by age at diagnosis, latency period, period of diagnosis, and type of initial treatment. Survival analysis was stratified by development of SPC. Men with primary prostate cancer had an overall lower risk of developing an SPC [SIR = 0.75; 95% CI, 0.72−0.78], which was significant for SPCs of the esophagus, stomach, rectum, liver, gallbladder, bile duct, pancreas, larynx, lung, and bronchus. In contrast, there were significant increases in the risk of bladder and thyroid cancers, which tended to decrease after longer follow-up. Patients who received initial radiation therapy had an increased risk of subsequent rectal cancer, although this was still lower than that of the general male population. Other urinary tract cancers including those of the kidney, renal pelvis, and ureter tended to be associated with a higher risk of developing an SPC, but this difference did not reach statistical significance. The patients with prostate cancer and SPC had lower overall survival rates than those with one primary prostate cancer. Our findings suggest that men with prostate cancer have a 25% lower risk of developing an SPC in Korea, but a higher risk of developing subsequent bladder and thyroid cancers, which suggests the need for continued cancer surveillance among prostate cancer survivors.     

Risk of Breast Cancer in Females With Hypothyroidism: A Nationwide,Population-Based,Cohort Study

ObjectivesThe results of studies investigating the relationship between breast cancer and hypothyroidism vary greatly from study to study. In this study, we analyzed a large and reliable, population-based database to gain a better understanding of the correlation.MethodsThis retrospective cohort study analyzed patients with hypothyroidism between January 1, 2000 and December 31, 2012 (hypothyroidism cohort) from the Longitudinal Health Insurance Database 2000 in Taiwan. For each woman with hypothyroidism, 1 woman without a history of breast cancer was randomly selected from the Longitudinal Health Insurance Database 2000 and frequency matched (1:4) with women without hypothyroidism by age and index year of hypothyroidism. The study outcome was the diagnosis of breast cancer during a 12-year follow-up period.ResultsIn this study, 6665 women with hypothyroidism and 26 660 women without hypothyroidism were identified. The hypothyroidism cohort had a significantly higher risk of breast cancer than the nonhypothyroidism cohort (adjusted hazard ratio [aHR] 1.69 [95% CI, 1.15-2.49]; P = .01), especially in the group aged 40 to 64 years (aHR 2.07 [95% CI, 1.32-3.23]; P = .01). Women in the hypothyroidism cohort taking levothyroxine for a duration ˃588 days showed a significantly decreased risk of breast cancer (aHR 0.37 [95% CI, 0.19-0.71]; P = .003).ConclusionWomen with hypothyroidism are at a higher risk of breast cancer than those without hypothyroidism. Levothyroxine may reduce the risk of breast cancer in a woman with hypothyroidism.     

Hospital Admissions in Children with Down Syndrome: Experience of a Population-Based Cohort Followed from Birth

Objective

Children with Down syndrome, the most common genetic cause of intellectual disability, are prone to multiple and varied health-related problems. This study describes patterns of hospitalisations for children and young people with Down syndrome in Western Australia.

Methods

Birth records were linked to the Western Australian population-based Intellectual Disability database to identify all children born with Down syndrome in Western Australia between 1 January, 1983 and 31 December, 1999. These records were linked to the Hospital Morbidity Data System to provide information on all hospitalisations up to 31 December, 2004. Hospitalisation data, coded using ICD-9CM or ICD-10 (v0.5) were grouped into clinically relevant categories using the primary diagnosis. Rates of hospital admission for all and specific diagnoses were expressed in 1000-person-years at-risk and median age at first admission and length of stay were calculated.

Results

Of the 405 children, 395 had one or more hospital admissions, totalling 3786 admissions for all children and an estimated 39.5 person-years in hospital. On average, children were admitted 9.7 times, with an estimated rate of 757.2 admissions per 1000pyr (95% CI: 680, 843). A quarter of all admissions occurred in the first year of life. The average hospital length of stay was 3.8 days (95% CI: 3.7, 4.1). Upper respiratory tract conditions affected the most children (58.5%) and accounted for 12.1% of all admissions. Other disorders which affected a high percentage of children were ear/hearing conditions (50.6%), disorders of the oral cavity (38.0%) and lower respiratory tract conditions (37.5%). Overall, children with Down syndrome were hospitalised at a rate five times (95% CI = 4.3–6.2) that of the general population.

Conclusion

Children with Down syndrome are at increased risk of morbidity for varied causes underlining the importance of comprehensive and targeted primary care for this group.     

The Risk of Asthma in Patients with Ankylosing Spondylitis: A Population-Based Cohort Study

BackgroundThe relationship between asthma and ankylosing spondylitis (AS) is controversial. We examined the risk of asthma among AS patients in a nationwide population.MethodsWe conducted a retrospective cohort study using data from the National Health Insurance (NHI) system of Taiwan. The cohort included 5,974 patients newly diagnosed with AS from 2000 to 2010. The date of diagnosis was defined as the index date. A 4-fold of general population without AS was randomly selected frequency matched by age, gender and the index year. The occurrence and hazard ratio (HR) of asthma were estimated by the end of 2011.ResultsThe overall incidence of asthma was 1.74 folds greater in the AS cohort than in the non-AS cohort (8.26 versus 4.74 per 1000 person-years) with a multivariable Cox method measured adjusted HR of 1.54 (95% confidence interval (CI), 1.34–1.76). The adjusted HR of asthma associated with AS was higher in women (1.59; 95% CI, 1.33–1.90), those aged 50–64 years (1.66; 95% CI, 1.31–2.09), or those without comorbidities (1.82; 95% CI, 1.54–2.13).ConclusionPatients with AS are at a higher risk of developing asthma than the general population, regardless of gender and age. The pathophysiology needs further investigation.     

Risks of Breast and Endometrial Cancer in Women with Diabetes: A Population-Based Cohort Study

Objective

We investigated the overall and age-specific risks of developing breast and endometrial cancer among women with diabetes in a population-based cohort study.

Methods

Women with diabetes (n = 319310) and age-matched controls (n = 319308), selected from ambulatory care claims and beneficiary registry in 2000, respectively were linked to the in-patient claims (2000–2008) to identify admissions due to breast (ICD-9-CM: 174) and endometrial (ICD-9-CM: 182) cancer. The person-year approach with Poisson assumption was used to estimate the incidence density rate. The age-specific hazard ratios (HRs) of above malignancies in relation to diabetes with multivariate Cox proportional hazard regression.

Results

The overall incidence density rate of breast and endometrial cancer was estimated at 1.21 and 0.21 per 10,000 patient-years, respectively, for diabetes. The corresponding figures for controls were lower at 1.00 and 0.14 per 10,000 patient-years. Compared with the controls, the covariate adjusted HR for breast and endometrial cancer was 1.42 (95% confidence interval (CI) 1.34–1.50) and 1.71 (95% CI 1.48–1.97), respectively in women with diabetes. Elderly (> = 65 years) diabetes had the highest HR (1.61) of breast cancer, while the highest HR (1.85) of endometrial cancer was observed in diabetes aged < = 50 years.

Conclusions

Diabetes may significantly increase the risks of breast and endometrial cancer in all age stratifications. Health education for strict adherence of cancer screening program in women with diabetes is essential.     

Increased Risk of Acute Pancreatitis in Patients with Rheumatoid Arthritis: A Population-Based Cohort Study

The study was conducted to determine whether patients with rheumatoid arthritis (RA) are at increased risk of acute pancreatitis compared with those without RA and to determine if the risk of acute pancreatitis varied by anti-RA drug use. We used the large population-based dataset from the National Health Insurance (NHI) program in Taiwan to conduct a retrospective cohort study. Patients newly diagnosed with RA between 2000 and 2011 were referred to as the RA group. The comparator non-RA group was matched with propensity score, using age and sex, in the same time period. We presented the incidence density by 100,000 person-years. The propensity score and all variables were analyzed in fully adjusted Cox proportional hazard regression. The cumulative incidence of acute pancreatitis was assessed by Kaplan-Meier analysis, with significance based on the log-rank test. From claims data of one million enrollees randomly sampled from the Taiwan NHI database, 29,755 adults with RA were identified and 119,020 non- RA persons were matched as a comparison group. The RA cohort had higher incidence density of acute pancreatitis (185.7 versus 119.0 per 100,000 person-years) than the non-RA cohort. The adjusted hazard ratio (HR) was 1.62 (95% CI [confidence interval] 1.43–1.83) for patients with RA to develop acute pancreatitis. Oral corticosteroid use decreased the risk of acute pancreatitis (adjusted HR 0.83, 95% CI 0.73–0.94) but without a dose-dependent effect. Current use of disease modifying anti-rheumatic drugs or tumor necrosis factor blockers did not decrease the risk of acute pancreatitis. In conclusion, patients with RA are at an elevated risk of acute pancreatitis. Use of oral corticosteroids may reduce the risk of acute pancreatitis.     

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.     

Preeclampsia as a Risk Factor for Diabetes: A Population-Based Cohort Study

Background

Women with preeclampsia (PEC) and gestational hypertension (GH) exhibit insulin resistance during pregnancy, independent of obesity and glucose intolerance. Our aim was to determine whether women with PEC or GH during pregnancy have an increased risk of developing diabetes after pregnancy, and whether the presence of PEC/GH in addition to gestational diabetes (GDM) increases the risk of future (postpartum) diabetes.

Methods and Findings

We performed a population-based, retrospective cohort study for 1,010,068 pregnant women who delivered in Ontario, Canada between April 1994 and March 2008. Women were categorized as having PEC alone (n = 22,933), GH alone (n = 27,605), GDM alone (n = 30,852), GDM+PEC (n = 1,476), GDM+GH (n = 2,100), or none of these conditions (n = 925,102). Our main outcome was a new diagnosis of diabetes postpartum in the following years, up until March 2011, based on new records in the Ontario Diabetes Database. The incidence rate of diabetes per 1,000 person-years was 6.47 for women with PEC and 5.26 for GH compared with 2.81 in women with neither of these conditions. In the multivariable analysis, both PEC alone (hazard ratio [HR] = 2.08; 95% CI 1.97–2.19) and GH alone (HR = 1.95; 95% CI 1.83–2.07) were risk factors for subsequent diabetes. Women with GDM alone were at elevated risk of developing diabetes postpartum (HR = 12.77; 95% CI 12.44–13.10); however, the co–presence of PEC or GH in addition to GDM further elevated this risk (HR = 15.75; 95% CI 14.52–17.07, and HR = 18.49; 95% CI 17.12–19.96, respectively). Data on obesity were not available.

Conclusions

Women with PEC/GH have a 2-fold increased risk of developing diabetes when followed up to 16.5 years after pregnancy, even in the absence of GDM. The presence of PEC/GH in the setting of GDM also raised the risk of diabetes significantly beyond that seen with GDM alone. A history of PEC/GH during pregnancy should alert clinicians to the need for preventative counseling and more vigilant screening for diabetes. Please see later in the article for the Editors'' Summary     

COPD and the Risk of Tuberculosis - A Population-Based Cohort Study

Background

Both chronic obstructive pulmonary disease (COPD) and tuberculosis (TB) primarily affect the lungs and are major causes of morbidity and mortality worldwide. COPD and TB have common risk factors such as smoking, low socioeconomic status and dysregulation of host defence functions. COPD is a prevalent co-morbid condition, especially in elderly with TB but in contrast to other diseases known to increase the risk of TB, relatively little is known about the specific relationship and impact from COPD on TB-incidence and mortality.

Methods and Findings

All individuals ≥40 years of age, discharged with a diagnosis of COPD from Swedish hospitals 1987–2003 were identified in the Swedish Inpatient Register (n = 115,867). Records were linked to the Swedish Tuberculosis Register 1989–2007 and the relative risk of active TB in patients with COPD compared to control subjects randomly selected from the general population (matched for sex, year of birth and county of residence) was estimated using Cox regression. The analyses were stratified by year of birth, sex and county of residence and adjusted for immigration status, socioeconomic status (SES) and inpatient co-morbidities previously known to increase the risk of TB. COPD patients had a three-fold increased hazard ratio (HR) of developing active TB (HR 3.0 (95% confidence interval 2.4 to 4.0)) that was mainly dependent on an increased risk of pulmonary TB. In addition, logistic regression estimates showed that COPD patients who developed active TB had a two-fold increased risk of death from all causes within first year after the TB diagnosis compared to the general population control subjects with TB (OR 2.2, 95% confidence interval 1.2 to 4.1).

Conclusions

This population-based study comprised of a large number of COPD patients shows that these patients have an increased risk of developing active TB compared to the general population. The results raise concerns that the increasing global burden of COPD will increase the incidence of active TB. The underlying contributory factors need to be disentangled in further studies.     

Recipient Age and Mortality Risk after Liver Transplantation: A Population-Based Cohort Study

The aim of the present large population-based cohort study is to explore the risk factors of age-related mortality in liver transplant recipients in Taiwan. Basic information and data on medical comorbidities for 2938 patients who received liver transplants between July 1, 1998, and December 31, 2012, were extracted from the National Health Insurance Research Database on the basis of ICD-9-codes. Mortality risks were analyzed after adjusting for preoperative comorbidities and compared among age cohorts. All patients were followed up until the study endpoint or death. This study finally included 2588 adults and 350 children [2068 (70.4%) male and 870 (29.6%) female patients]. The median age at transplantation was 52 (interquartile range, 43–58) years. Recipients were categorized into the following age cohorts: <20 (n = 350, 11.9%), 20–39 (n = 254, 8.6%), 40–59 (n = 1860, 63.3%), and ≥60 (n = 474, 16.1%) years. In the total population, 428 deaths occurred after liver transplantation, and the median follow-up period was 2.85 years (interquartile range, 1.2–5.5 years). Dialysis patients showed the highest risk of mortality irrespective of age. Further, the risk of death increased with an increase in the age at transplantation. Older liver transplant recipients (≥60 years), especially dialysis patients, have a higher mortality rate, possibly because they have more medical comorbidities. Our findings should make clinicians aware of the need for better risk stratification among elderly liver transplantation candidates.     

Sarcoidosis in Patients with Psoriasis: A Population-Based Cohort Study

Purpose

Psoriasis is a chronic inflammatory disease characterized by a systemic immunological response which is mainly driven by activated T helper (Th) 1 and Th17 lymphocytes. Like psoriasis, sarcoidosis is a chronic inflammatory disorder with Th1/Th17-driven inflammation. Therefore, we investigated the risk of sarcoidosis in patients with psoriasis compared to the background population in a nationwide cohort.

Methods

The study included the entire Danish population aged ≥10 years followed from 1^st January 1997 until diagnosis of sarcoidosis, death or 31^st December 2011. Patients with a history of psoriasis and/or sarcoidosis at baseline were excluded. Information on comorbidity and concomitant medication was identified by individual-level linkage of administrative registers. Incidence rates of sarcoidosis were calculated and adjusted hazard ratios (HRs) were estimated by multivariable Cox regression models adjusted for age, gender, comorbidity, medications and socioeconomic status.

Results

A total of 6,043,518 subjects were eligible for analysis. In the study period 70,125 patients with new-onset psoriasis, including 11,834 patients with severe psoriasis, were identified. The overall incidence rates of sarcoidosis were 1.18, 2.22, and 4.06 per 10,000 person-years for the reference population (9,717 cases), mild psoriasis (78 cases) and severe psoriasis (22 cases), respectively. Compared to the reference population, the age- and gender-adjusted HRs for sarcoidosis were increased in patients with psoriasis with HR 1.49 (95% confidence interval [CI] 1.18–1.87) and HR 2.51 (CI 1.64–3.85) for those with mild and severe disease, respectively.

Conclusion

In this nationwide cohort, psoriasis was associated with a disease severity-dependent increased risk of sarcoidosis.     

Seropositivity of Lyme Borreliosis and Associated Risk Factors: A Population-Based Study in Children and Adolescents in Germany (KiGGS)

Background

Lyme borreliosis (LB) caused by spirochetes of the Borrelia burgdorferi sensu lato complex is the most common tick-borne disease in the northern hemisphere. Data on the distribution and on risk factors in Germany are sketchy.

Methodology/Principal Findings

Blood samples of a nationwide population-based cross-sectional study from 2003–2006 in children and adolescents aged 1 to 17 years in Germany (KiGGS) were analysed (n = 12,614) to assess the seroprevalence of anti-Borrelia antibodies. Data from standardized interviews were used to assess potential risk factors. First, sera were screened for anti-Borrelia antibodies by ELISA. The overall prevalence was 4.8% (95% confidence interval (CI) 4.3–5.4%). Positive and borderline ELISA test results were confirmed by a line blot revealing a combined prevalence of 4.0% (95% CI 3.6–4.5%). Seroprevalence of ELISA was significantly higher in males (odds ratio (OR) = 1.37; CI 1.15–1.63) and in the southern part of Germany (OR = 1.41; CI 1.09–1.83), but significantly lower in children and adolescents with migration background (OR = 0.33; CI 0.24–0.44). Study participants from households with cats had a higher chance of seropositivity (OR = 6.7; CI 5.6–8.0). In a multivariable model the odds of seropositivity increases by 11% for every year of age for boys and 6% for girls.

Conclusions/Significance

This survey is the first nationwide, representative seroprevalence survey of LB in children and young adolescents. The study shows that infections with Borrelia burgdorferi are endemic in all parts of Germany despite regional differences. Even at a young age children are exposed to tick bites including seropositivity. Encouraging a thorough check for ticks and promptly removal of ticks are the key public health strategies to reduce the risk of LB and other tick-borne diseases in children and adolescents. Further epidemiological studies are warranted to better understand the burden of disease related to LB.     

Sleep Duration Trajectories and Body Composition in Adolescents: Prospective Birth Cohort Study

We aimed to estimate the association between sleep duration trajectories and body composition in adolescents. We used data from participants of the 1993 Pelotas (Brazil) Birth Cohort Study who were later followed up at age 18 years (response rate of 81.3%). At the time, 3974 adolescents had complete data on body composition, which was assessed by air displacement plethysmography. Sleep duration was self-reported by participants at ages 11 and 18 years. Analyses were sex-stratified. The mean sleep duration at 11 years was 9.7 (SD 1.4) and 8.4 (SD 1.9) at 18 years. Sleep duration was dichotomized as inadequate (<8 hours/day) or adequate (≥8 hours/day). Mean body mass, fat mass, and fat-free mass indices at 18 years were 23.4 kg/m² (SD 4.5), 6.1 kg/m² (SD 3.9) and 17.3 kg/m² (SD 2.5), respectively. Girls who reported inadequate sleep duration at 11 years of age, but adequate sleep duration at 18, on average experienced an increase in body mass index (β = 0.39 z-scores; 95% CI 0.13, 0.65), fat mass index (β = 0.30 z-scores; 95% CI 0.07, 0.53), and fat-free mass index (β = 0.24 z-scores; 95% CI 0.08, 0.39) compared to those who had adequate sleep duration at both time points. The results suggest that changes in sleep duration across adolescence may impact body composition in later adolescence and that this may differ by sex.     

Maternal Age,Parity and Isolated Birth Defects: A Population-Based Case-Control Study in Shenzhen,China

Background

The etiology of birth defects has been widely studied but is not yet fully clarified, previously published data had suggested that maternal age or parity maybe involved, but without consistent conclusions.

Methods

A population-based, case-control study was nested in a cohort of perinatal infants born from 2010 to 2012 in Baoan District, Shenzhen. Four categories of isolated birth defects were defined as cases: congenital heart defects (CHD, n = 693), polydactyly (n = 352), cleft lip with or without palate (CL/P, n = 159) and equinovarus (n = 119). Controls were non-malformed infants (n = 11,307) randomly selected from the same area and period. Odds ratios (ORs) and the 95% confidence intervals (CIs) were computed by multivariable unconditional logistic regression analysis.

Results

Young maternal age (<25 years old) was associated with a reduced risk of CHD (adjusted OR = 0.73, 95% CI 0.59–0.90), while with an elevated risk of polydactyly (adjusted OR = 1.42, 95% CI 1.09-1.84). Increased risk of CL/P-affected pregnancy was observed in mothers older than 35 years old (adjusted OR = 2.12, 95% CI 1.26–3.57). Compared to primipara, those having their second, and third or more delivery were less likely to have infants with equinovarus, with significant adjusted ORs of 0.59 (0.40–0.89) and 0.42 (0.19–0.93), respectively.

Conclusion

Maternal age was significantly associated with CHD, polydactyly and CL/P relevant pregnancy. Mothers with higher parity might have lower risk of equinovarus occurrence in offsprings.     

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 Obstructive Sleep Apnea in Adult Patients with Asthma: A Population-Based Cohort Study in Taiwan

Background

There are several publications reported that obstructive sleep apnea (OSA) was associated with asthma. However, large-scaled, population-based cohort study has been limited. We aimed to examine the risk of OSA among adult patients with asthma in an Asian population.

Methods

We conducted a retrospective cohort study using data from the National Health Insurance (NHI) of Taiwan. The asthma cohort included 38,840 newly diagnosed patients between 2000 and 2010. The date of diagnosis was defined as the index date. Each patient was randomly matched with four people without asthma according to gender, age, and the index year as the comparison cohort. The occurrence of OSA was followed up until the end of 2011. The risk of OSA was estimated using the Cox proportional hazard model after adjusting for gender, age, and comorbidities.

Results

The overall incidence of OSA was 2.51-fold greater in the asthma cohort than in the comparison cohort (12.1 versus 4.84 per 1000 person-years). Compared to non-asthma subjects, the adjusted hazard ratio (aHR) of OSA increased to 1.78 for asthma patients with one or less annual emergency room (ER) visit, and 23.8 for those who visited ER more than once per year. In addition, aHR in patients with inhaled steroid treatment compared to those without steroid treatment was 1.33 (95% CI = 1.01–1.76).

Conclusion

Patients with asthma have a significantly higher risk of developing OSA than the general population. The results suggest that the risk of OSA is proportional to asthma control and patients with inhaled steroid treatment have a higher risk for OSA than those without steroid treatment.     

The Protective Effect of Adenoidectomy on Pediatric Tympanostomy Tube Re-Insertions: A Population-Based Birth Cohort Study

Objectives

Adenoidectomy in conjunction with tympanostomy tube insertion for treating pediatric otitis media with effusion and recurrent acute otitis media has been debated for decades. Practice differed surgeon from surgeon. This study used population-based data to determine the protective effect of adenoidectomy in preventing tympanostomy tube re-insertion and tried to provide more evidence based information for surgeons when they do decision making.

Study Design

Retrospective birth cohort study.

Methods

This study used the National Health Insurance Research Database for the period 2000–2009 in Taiwan. The tube reinsertion rate and time to tube re-insertion among children who received tympanostomy tubes with or without adenoidectomy were compared. Age stratification analysis was also done to explore the effects of age.

Results

Adenoidectomy showed protective effects on preventing tube re-insertion compared to tympanostomy tubes alone in children who needed tubes for the first time (tube re-insertion rate 9% versus 5.1%, p = 0.002 and longer time to re-insertions, p = 0.01), especially those aged over 4 years when they had their first tube surgery. After controlling the effect of age, adenoidectomy reduced the rate of re-insertion by 40% compared to tympanostomy tubes alone (aHR: 0.60; 95% CI: 0.41–0.89). However, the protective effect of conjunction adenoidectomy was not obvious among children with a second tympanostomy tube insertion. Children who needed their first tube surgery at the age 2–4 years were most prone to have tube re-insertions, followed by the age group of 4–6 years.

Conclusions

Adenoidectomy has protective effect in preventing tympanostomy tube re-insertions compared to tympanostomy tubes alone, especially for children older than 4 years old and who needed tubes for the first time. Nonetheless, clinicians should still weigh the pros and cons of the procedure for their pediatric patients.     

Significantly Increased Risk of Cardiovascular Disease among Patients with Gallstone Disease: A Population-Based Cohort Study

Objective

To investigate whether gallstone disease (GD) increases the risk of developing cardiovascular disease (CVD) in a large population-based cohort.

Methods

A study population including 6,981 patients with GD was identified from The Taiwan National Health Insurance Research Database between 2004 and 2005. GD patients were defined as patients with principal discharge diagnoses of cholelithiasis using the ICD-9-CM code 574. 27,924 patients without GD were randomly selected and matched for age and gender. All patients were followed for 6 years or until diagnosis for CVD. Cox proportional hazards regression model was used to assess the risk of developing CVD with adjustment for age, gender and co-morbid conditions.

Results

During the six years follow-up period, 935 patients with GD and 2,758 patients without GD developed CVD. Patients with GD had an elevated risk of CVD (HR, 1.32; 95% CI, 1.22-1.43) when compared with those without GD. Similar relationship was observed when CVD was categorized i.e. stroke (HR, 1.15; 95% CI, 1.01-1.32), coronary heart disease (HR, 1.42; 95% CI, 1.28-1.58) and heart failure (HR, 1.31; 95% CI, 1.00-1.73). When GD was classified according to the level of severity, using patients without GD as reference, the risks of CVD were elevated in patients with non-severe GD (HR, 1.34; 95% CI, 1.24-1.46) as well as those with severe GD (HR, 1.20, 95% CI, 1.02-1.40), after adjusting for age, gender and comorbidities. In age-stratified analysis, patients aged 18-40 years with GD were at higher risk of developing CVD (HR, 1.42; 95% CI, 1.09-1.84) than older GD patients.

Conclusion

This study found an increased risk of CVD in patients diagnosed with GD. The excess risk was particularly high in younger GD patients. Prevention of GD could help reduce the risk of developing CVD, and the better effect could be achieved for the younger age groups.     

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.