Hospital-associated venous thromboembolism in children: incidence and clinical characteristics

OBJECTIVE

To determine incidence and clinical characteristics of hospital-associated venous thromboembolism (VTE) in pediatric patients.

STUDY DESIGN

A retrospective analysis of patients with hospital-associated VTE at the Johns Hopkins Hospital from 1994 to 2009 was performed. Clinical characteristics of patients aged 21 years and younger who developed VTE symptoms after 2 days of hospitalization or <90 days after hospital discharge were examined. International Classification of Diseases, Ninth Revision codes were used to categorize patients with complex chronic medical conditions and trauma.

RESULTS

There were 270 episodes of hospital-associated VTE in 90,485 admissions (rate 30 per 10,000 admissions). Young adults (18-21 years) and adolescents (14-17 years) had significantly increased rates of VTE compared with children (2-9 years) (incidence rate ratio [IRR] 7.7, 95% CI 5.1-12.0; IRR 4.3, 95% CI 2.7-6.8, respectively). A central venous catheter (CVC) was present in 50% of patients, and a surgical procedure was performed in 45% of patients before VTE diagnosis. For patients without a CVC, trauma was the most common admitting diagnosis. CVC-related VTE was diagnosed most frequently in infants (<1 year old) and in patients with malignancy. Renal and cardiac diseases were associated with the highest rates of VTE (51 and 48 per 10,000, respectively). Rates were significantly higher among those with ≥ 4 medical conditions compared with those with 1 medical condition (IRR 4.0, 95% CI 1.4-8.9).

CONCLUSION

Older age and multiple medical conditions were associated with increased rates of hospital-associated VTE. These data can contribute to the design of future clinical trials to prevent hospital-associated VTE in high-risk children.

Association of a genetic variant of carnitine palmitoyltransferase 1A with infections in Alaska Native children

OBJECTIVE

To evaluate whether the arctic variant (c.1436C→T) of carnitine palmitoyltransferase type 1A (CPT1A) is associated with a higher incidence of adverse health outcomes in Alaska Native infants and children.

STUDY DESIGN

We evaluated health measures from birth certificates (n = 605) and Alaska Medicaid billing claims (n = 427) collected from birth to 2.5 years of age for a cohort of Alaska Native infants with known CPT1A genotype. To account for geographic variations in gene distribution and other variables, data also were evaluated in cohorts.

RESULTS

When analysis was restricted to residents of nonhub communities in Western and Northern Alaska, children homozygous for the arctic variant experienced more episodes of lower respiratory tract infection than did heterozygous or noncarrier children (5.5 vs 3.7, P = .067) and were more likely to have had otitis media (86% vs 69%, 95% CI 1.4-8.9). Associations were weaker for more homogeneous cohorts.

CONCLUSIONS

The association of the arctic variant of CPT1A with infectious disease outcomes in children between birth and 2.5 years of age suggests that this variant may play a role in the historically high incidence of these health outcomes among indigenous Arctic populations; further studies will need to assess if this association was confounded by other risk factors.

Risk of lymphoma in patients with ulcerative colitis treated with thiopurines: a nationwide retrospective cohort study

BACKGROUND & AIMS

There is controversy over whether the treatment of patients with ulcerative colitis (UC) with thiopurines increases their risk of lymphoma. We evaluated the risk of lymphoma (ongoing, residual, and per year of therapy) among thiopurine-treated patients with UC.

METHODS

We obtained nationwide data from the Veterans Affairs (VA) health care system from 2001 to 2011. We performed a retrospective cohort study, analyzing data on 36,891 patients from their date of diagnosis of UC in the VA health care system to a diagnosis of lymphoma or October 1, 2011 (subjects followed up for a median of 6.7 years). Thiopurine exposure was assessed using the VA pharmacy database. Patients who developed lymphoma were identified based on ICD-9 codes and confirmed by manual chart review.

RESULTS

In total, 4734 patients with UC (13%) were treated with thiopurines for a median of 1 year. Lymphoma developed in 119 patients who had not been treated with thiopurines, 18 who were treated with thiopurines, and 5 who had discontinued treatment with thiopurines. The incidence rates of lymphoma were 0.60 per 1000 person-years among patients who had not been treated with thiopurines, 2.31 among patients who were treated with thiopurines, and 0.28 among patients who had discontinued treatment with thiopurines. The incidence rates of lymphoma during the first year, second year, third year, fourth year, and >4 years of thiopurine therapy were 0.9, 1.6, 1.6, 5, and 8.9 per 1000 person-years, respectively. The age-, sex-, and race-adjusted hazard ratios of developing lymphoma were 4.2 (95% confidence interval, 2.5-6.8; P < .0001) while being treated with thiopurines and 0.5 (95% confidence interval, 0.2-1.3; P = .17) after discontinuing treatment with thiopurines compared with patients who had not been treated with thiopurines.

CONCLUSIONS

Based on a retrospective, nationwide cohort study, patients with UC have a 4-fold increase in risk of lymphoma while being treated with thiopurines compared with patients who have not been treated with thiopurines. The risk increases gradually for successive years of therapy. Discontinuing thiopurine therapy reduces the risk of lymphoma.

Chronic obstructive pulmonary disease and association with mild cognitive impairment: the Mayo Clinic Study of Aging

OBJECTIVE

To investigate the association of chronic obstructive pulmonary disease (COPD) with mild cognitive impairment (MCI) and MCI subtype: amnestic MCI and nonamnestic MCI, in a population-based study of elderly patients.

PATIENTS AND METHODS

Participants included 1927 individuals aged 70 to 89 years enrolled in the population-based Mayo Clinic Study of Aging. Participants were evaluated by using a nurse assessment, neurological evaluation, and neuropsychological testing, and the diagnosis of MCI was made by a consensus panel according to the standardized criteria. Chronic obstructive pulmonary disease was identified by the review of medical records. The study was conducted from October 1, 2004, through July 31, 2007. The associations of COPD and disease duration with MCI and its subtypes were evaluated by using logistic regression models adjusted for potential covariates.

RESULTS

Of 1927 participants, 288 had COPD (men vs women: 18% vs 12%; P<.001). As compared with patients without COPD, patients with COPD had a higher prevalence of MCI (27% vs 15%; P<.001). The odds ratio (OR) for MCI was almost 2 times higher in patients with COPD than in those without (OR, 1.87; 95% CI, 1.34-2.61), with a similar effect in men and women. The OR for MCI increased from 1.60 (95% CI, 0.97-2.57) in patients with a COPD duration of 5 years or less to 2.10 (95% CI, 1.38-3.14) in patients with a COPD duration of more than 5 years.

CONCLUSION

This population-based study suggests that COPD is associated with increased odds of having MCI and its subtypes. There was a dose-response relationship with the duration of COPD after controlling for the potential covariates.

Characteristics of resistant hypertension in a large, ethnically diverse hypertension population of an integrated health system

OBJECTIVE

To evaluate the prevalence of and characterize resistant hypertension in a large representative population with successful hypertension management and reliable health information.

PATIENT AND METHODS

We performed a cross-sectional study using clinical encounter, laboratory, and administrative information from the Kaiser Permanente Southern California health system between January 1, 2006, and December 31, 2007. From individuals older than 17 years with hypertension, resistant hypertension was identified and prevalence was determined. Multivariable logistic regression was used to calculate odds ratios (ORs), with adjustments for demographic characteristics, clinical variables, and medication use.

RESULTS

Of 470,386 hypertensive individuals, 60,327 (12.8%) were identified as having resistant disease, representing 15.3% of those taking medications. Overall, 37,061 patients (7.9%) had uncontrolled hypertension while taking 3 or more medicines. The ORs (95% CIs) for resistant hypertension were greater for black race (1.68 [1.62-1.75]), older age (1.11 [1.10-1.11] for every 5-year increase), male sex (1.06 [1.03-1.10]), and obesity (1.46 [1.42-1.51]). Medication adherence rates were higher in those with resistant hypertension (93% vs 89.8%; P<.001). Chronic kidney disease (OR, 1.84; 95% CI, 1.78-1.90), diabetes mellitus (OR, 1.58; 95% CI, 1.53-1.63), and cardiovascular disease (OR, 1.34; 95% CI, 1.30-1.39) were also associated with higher risk of resistant hypertension.

CONCLUSION

In a more standardized hypertension treatment environment, we observed a rate of resistant hypertension comparable with that of previous studies using more fragmented data sources. Past observations have been limited due to nonrepresentative populations, reliability of the data, heterogeneity of the treatment environments, and less than ideal control rates. This cohort, which was established using an electronic medical record-based approach, has the potential to provide a better understanding of resistant hypertension and outcomes.

Low morbidity and mortality in children with diabetic ketoacidosis treated with isotonic fluids

OBJECTIVE

To assess current rates of complications of diabetic ketoacidosis (DKA), particularly cerebral edema, in a large tertiary-care pediatric hospital with a consistent management protocol.

STUDY DESIGN

We report our single-center retrospective experience with 3712 admissions with DKA in 1999-2011. Our DKA protocol features a "3-bag" system using 2 bags of rehydration fluids, identical except for the presence in 1 bag of 10% dextrose, to allow rapid adjustment of glucose infusion rate. The third bag contains insulin. Fluids are administered at a total rate of 2-2.5 times "maintenance" fluid requirements. Total electrolyte concentration is kept approximately isotonic. Billing and medical records databases at Children's Medical Center Dallas were examined for cases of DKA, cerebral edema, other morbidities, and death.

RESULTS

We ascertained 20 cases of cerebral edema (0.5%). Most presented early (median duration of treatment 2 hours). Only 10 of 20 computed tomography scans were graded as moderate edema or worse. Only 10 patients received treatment other than routine DKA management. There was 1 death in a patient with sickle cell trait who developed intravascular sickling. Two patients had neurologic sequelae at hospital discharge but both recovered fully.

CONCLUSIONS

Compared with data in recent consensus statements, the Dallas protocol is associated with extremely low rates of death and disability (0.08% vs 0.3%) from DKA.

Atopic diathesis in patients with Kawasaki disease

OBJECTIVE

To determine the association between Kawasaki disease (KD) and atopic diathesis (atopic dermatitis [AD], allergic rhinitis, and asthma) in children younger than 5 years of age.

STUDY DESIGN

In this nationwide study, we aimed to analyze the association and temporal relationship between KD and atopic diathesis. Data were obtained from the National Health Insurance Research Database of Taiwan from 1997 to 2010. In total, 200 patients with KD younger than 5 years of age and 800 age- and sex-matched control subjects were enrolled.

RESULTS

In the whole study population, an increased risk of any concomitant atopic diseases was observed in patients with KD (OR 1.61, 95% CI 1.15-2.26). The risk of AD was increased in male patients between 1 and 5 years of age (OR 3.02, 95% CI 1.22-7.50). More than 60% of the patients developed atopic diseases after the diagnosis of KD.

CONCLUSION

There appears to be an association between KD and risk of AD. Most of the atopic diseases occurred after the episode of KD.

Neonatal health of infants born to mothers with asthma

BACKGROUND

Maternal asthma is associated with serious pregnancy complications, but newborn morbidity is understudied.

OBJECTIVE

We wanted to determine whether infants of asthmatic mothers have more neonatal complications.

METHODS

The Consortium on Safe Labor (2002-2008), a retrospective cohort, included 223,512 singleton deliveries at ≥ 23 weeks' gestation. Newborns of mothers with asthma (n = 17,044) were compared with newborns of women without asthma by using logistic regression models with generalized estimating equations to calculate adjusted odds ratios (ORs) and 95% CIs. Electronic medical record data included gestational week at delivery, birth weight, resuscitation, neonatal intensive care unit (NICU) admission, NICU length of stay, hyperbilirubinemia, respiratory distress syndrome, apnea, sepsis, anemia, transient tachypnea of the newborn, infective pneumonia, asphyxia, intracerebral hemorrhage, seizure, cardiomyopathy, periventricular or intraventricular hemorrhage, necrotizing enterocolitis, aspiration, retinopathy of prematurity, and perinatal mortality.

RESULTS

Preterm delivery was associated with maternal asthma for each week after 33 completed weeks of gestation and not earlier. Maternal asthma also increased the adjusted odds of small for gestational age (OR = 1.10; 95% CI, 1.05-1.16), NICU admission (OR = 1.12; 95% CI, 1.07-1.17), hyperbilirubinemia (OR = 1.09; 95% CI, 1.04-1.14), respiratory distress syndrome (OR = 1.09; 95% CI, 1.01-1.19), transient tachypnea of the newborn (OR = 1.10; 95% CI, 1.02-1.19), and asphyxia (OR = 1.34; 95% CI, 1.03-1.75). Findings persisted for term infants (≥ 37 weeks) who had additional increased odds of intracerebral hemorrhage (OR = 1.84; 95% CI, 1.11-3.03) and anemia (OR = 1.30; 95% CI, 1.04-1.62).

CONCLUSIONS

Maternal asthma was associated with prematurity and small for gestational age. Adverse neonatal outcomes, including respiratory complications, hyperbilirubinemia, and NICU admission, were increased in association with maternal asthma even among term deliveries.

Association between consistent omalizumab treatment and asthma control

BACKGROUND

Omalizumab is indicated for patients with moderate-to-severe allergic asthma with inadequately controlled symptoms.

OBJECTIVE

We evaluated the association between consistent omalizumab treatment and asthma control.

METHODS

Health insurance claims from the MarketScan database (2002Q1-2011Q2) were analyzed. Asthmatic patients with ≥12 months of continuous insurance coverage after the first omalizumab claim (index date) after 6 months of continuous omalizumab use were included. A 12-month landmark period was used to assess treatment consistency, defined as uninterrupted treatment without a gap of ≥28 days in omalizumab use. The effect of consistent omalizumab treatment on asthma control between months 13 and 24 was evaluated. Multivariate time-varying Cox regressions were also conducted to assess the adjusted effect of treatment interruption on asthma control from month 1 to month 24.

RESULTS

A total of 3044 patients (mean age, 48.5 years; female, 62%) formed the study population. Patients consistent with omalizumab treatment at 12 months (39% of patients) were less likely to have an uncontrolled asthma event during months 13 to 24 with only 49% of patients experiencing one event compared with 54% in the non consistent subgroup (P = .02). In addition, consistent omalizumab treatment at 12 months was associated with a 51% reduction in the mean number of asthma-related emergency department (ED) visits per patient and a 28% reduction in asthma-related hospitalizations. Multivariate analyses corroborated these findings (hazard ratio for consistent vs non-consistent: risk of short-acting β2-agonists prescription, oral corticosteroids prescription, ED visit, or hospitalization, 0.76; 95% CI, 0.69-0.83]).

CONCLUSION

This analysis showed that consistent omalizumab treatment was associated with significant reductions in ED visits and hospitalizations.