Shahed Iqbal

Racial and Ethnic Disparities in Current Asthma and Emergency Department Visits: Findings from the National Health Interview Survey, 2001–2010

Objectives. Racial/ethnic disparities in current asthma prevalence and medical care are a major public health concern. We examined the differences in asthma prevalence and morbidity among major racial/ethnic populations in the US. Methods. We analyzed data from the 2001–2010 National Health Interview Survey for adults (≥18 years) and children and adolescents (<18 years). Outcome variables were current asthma prevalence, at least one attack in the past 12 months, and at least one asthma-related emergency department/urgent care center (ED/UCC) visit in the past 12 months. We used multivariate logistic regression to calculate the model-adjusted prevalence and risk ratios (ARR). Results. In our study, 9.0% of the children and 7.2% of the adults had current asthma. Non-Hispanic black and Puerto Rican children were more likely to have current asthma (ARR 1.46, 1.66, respectively) and to visit the ED/UCC (ARR 1.61, 1.67, respectively) than non-Hispanic whites. American Indian/Alaskan Native children were more likely to have current asthma (ARR 1.76) than non-Hispanic whites. Mexican/Mexican American children and adults had lower prevalence of current asthma but higher ED/UCC use (adults only) than non-Hispanic whites. Among adults, Puerto Ricans and American Indian/Alaskan Natives were more likely to have current asthma (ARR 1.60, 1.39, respectively) than non-Hispanic whites, and all the studied racial/ethnic groups except Asians were more likely to have visited the ED/UCC than non-Hispanic whites. Adults and children who received emergency care for asthma in the past 12 months more frequently received multiple components of asthma management and control (e.g., taking long-term medication, having an asthma management plan) compared to those without emergency care. Conclusions. Racial/ethnic differences in current asthma prevalence, asthma attacks, and increased utilization of emergency room visits for asthma among minorities persist among children and adults. Appropriate and effective asthma management and education may lead to better asthma control and reduce emergency care utilization.

Guillain-Barré Syndrome, Influenza and Influenza Vaccination—the Epidemiologic Evidence

Guillain-Barré syndrome (GBS) is the most common cause of acute flaccid paralysis worldwide, and is thought to be immune-mediated. It is preceded by upper respiratory or gastrointestinal infection in about two-thirds of cases and is associated with some viral infections, including influenza. GBS has also been associated with the 1976 swine-influenza vaccine. Thereafter, some studies have shown a small increased risk of GBS following receipt of seasonal and 2009 H1N1 monovalent influenza vaccines. Studies over the years have also shown an increased risk of GBS following influenza infection, and the magnitude of risk is several times greater than that following influenza vaccination. Because GBS is rare, and even rarer following vaccination, it is difficult to estimate precise risk. We try to shed light on the complex relationship of GBS and its association with influenza and influenza vaccines over the past 35 years.

Factors Associated with Asthma Control among Adults in Five New England States, 2006–2007

Background. Despite the National Asthma Education and Prevention Program (NAEPP) guidelines that specify the goals of asthma control and management strategies, the number of patients with uncontrolled asthma remains high, and factors associated with uncontrolled asthma are unknown. Objective. The aim was to examine the relationship between asthma control and socio-demographic characteristics, health-care access and use, asthma education, and medication use among adults with active asthma residing in New England. Methods. Data from the 2006–2007 Behavior Risk Factor Surveillance System Adult Asthma Call-Back Survey were analyzed using multinomial logistic regression. Asthma control was categorized as “well controlled,” “not well controlled,” or “very poorly controlled” according to the NAEPP guidelines. Results. Of the respondents (n = 3079), 30% met the criteria for well-controlled asthma, 46% for not well-controlled asthma, and 24% for very poorly controlled asthma. Being of Hispanic ethnicity (odds ratio [OR] = 4.0; 95% confidence interval [CI] = 1.2–13.7), unemployed or unable to work (OR = 17.9; 95% CI = 6.0–53.4), high school educated or less (OR = 2.8; 95% CI = 1.6–4.7), current smokers (OR = 2.5; 95% CI = 1.3–5.1), or being unable to see a doctor or specialist for asthma care or unable to buy medication for asthma because of cost (OR = 7.6; 95% CI = 3.4–17.1) were associated with very poorly controlled asthma. In addition, having Coronary Obstructive Pulmonary Disease (COPD) (OR = 2.6; 95% CI = 1.5–4.5), two or more routine checkups for asthma (OR = 4.5; 95% CI = 2.3–8.9), or an emergency department visit, urgent care facility visit, and hospitalization in the past year (OR = 3.9; 95% CI = 2.1–7.3) were also associated with having very poorly controlled asthma. Using controller medication in the past year (OR = 2.6; 95% CI = 1.6–4.2) and taking a course on how to manage asthma (OR = 3.0; 95% CI = 1.2–7.8) were significantly associated with poor asthma control. Conclusion. The high prevalence (70%) of not well-controlled asthma and poorly controlled asthma in this study emphasizes the need to identify factors associated with poor asthma control for development of targeted intervention. A health policy of increasing asthma education, health-care access, and smoking cessation may be effective and result in better asthma control and management.

A Review of Disaster-Related Carbon Monoxide Poisoning: Surveillance, Epidemiology, and Opportunities for Prevention

OBJECTIVES We conducted a systematic literature review to better understand aspects of disaster-related carbon monoxide (CO) poisoning surveillance and determine potentially effective prevention strategies. METHODS This review included information from 28 journal articles on disaster-related CO poisoning cases occurring between 1991 and 2009 in the United States. RESULTS We identified 362 incidents and 1888 disaster-related CO poisoning cases, including 75 fatalities. Fatalities occurred primarily among persons who were aged 18 years or older (88%) and male (79%). Hispanics and Asians accounted for 20% and 14% of fatal cases and 21% and 7% of nonfatal cases, respectively. Generators were the primary exposure source for 83% of fatal and 54% of nonfatal cases; 67% of these fatal cases were caused by indoor generator placement. Charcoal grills were a major source of exposure during winter storms. Most fatalities (94%) occurred at home. Nearly 89% of fatal and 53% of nonfatal cases occurred within 3 days of disaster onset. CONCLUSIONS Public health prevention efforts could benefit from emphasizing predisaster risk communication and tailoring interventions for racial, ethnic, and linguistic minorities. These findings highlight the need for surveillance and CO-related information as components of disaster preparedness, response, and prevention.

Carbon monoxide-related hospitalizations in the U.S.: evaluation of a web-based query system for public health surveillance.

Objective. Carbon monoxide (CO) poisoning is preventable, yet it remains one of the most common causes of poisoning in the U.S. In the absence of a national data reporting system for CO-poisoning surveillance, the burden of CO-related hospitalizations is unknown. Our objective was to generate the first national estimates of CO-related hospitalizations and to evaluate the use of a Web-based query system for public health surveillance. Methods. The Healthcare Cost and Utilization Projects (HCUPs) 2005 Nationwide Inpatient Sample (NIS) data were used for CO-related hospitalization estimates. Data for confirmed, probable, and suspected cases were generated using the HCUPnet Web-based query system. We used data from 1993 through 2005 NIS to describe trends in CO-related hospitalizations. We used the Centers for Disease Control and Preventions surveillance evaluation guidelines to evaluate the system. Results. In 2005, there were 24,891 CO-related hospitalizations nationwide: 16.9% (n=4,216) were confirmed, 1.1% (n=279) were probable, and 81.9% (n=20,396) were suspected CO-poisoning cases. Of the confirmed cases (1.42/100,000 population), the highest hospitalization rates occurred among males, older adults (aged ≥85 years), and Midwestern residents. CO-related hospitalization rates declined from 1993 through 2000 and plateaued from 2001 through 2005. The simplicity, acceptability, sensitivity, and representativeness of the HCUPnet surveillance system were excellent. However, HCUPnet showed limited flexibility and specificity. Conclusions. Nationwide, the burden of CO exposure resulting in hospitalization is substantial. HCUPnet is a useful surveillance tool that efficiently characterized CO-related hospitalizations for the first time. Public health practitioners can utilize this data source for state-level surveillance.

Carbon Monoxide Poisoning After an Ice Storm in Kentucky, 2009

Objectives. Carbon monoxide (CO) poisoning is a leading cause of morbidity and mortality during natural disasters. On January 26–27, 2009, a severe ice storm occurred in Kentucky, causing widespread, extended power outages and disrupting transportation and communications. After the storm, CO poisonings were reported throughout the state. The objectives of this investigation were to determine the extent of the problem, identify sources of CO poisoning, characterize cases, make recommendations to reduce morbidity and mortality, and develop prevention strategies. Methods. We obtained data from the Kentucky Regional Poison Center (KRPC), hyperbaric oxygen treatment (HBOT) facilities, and coroners. Additionally, the Kentucky Department for Public Health provided statewide emergency department (ED) and hospitalization data. Results. During the two weeks after the storm, KRPC identified 144 cases of CO poisoning; exposure sources included kerosene heaters, generators, and propane heaters. Hospitals reported 202 ED visits and 26 admissions. Twenty-eight people received HBOT. Ten deaths were attributed to CO poisoning, eight of which were related to inappropriate generator location. Higher rates of CO poisoning were reported in areas with the most ice accumulation. Conclusions. Although CO poisonings are preventable, they continue to occur in postdisaster situations. Recommendations include encouraging use of CO alarms, exploring use of engineering controls on generators to decrease CO exposure, providing specific information regarding safe use and placement of CO-producing devices, and using multiple communication methods to reach people without electricity.

National carbon monoxide poisoning surveillance framework and recent estimates.

Objectives. Unintentional, non-fire-related (UNFR) carbon monoxide (CO) poisoning is a leading cause of poisoning in the United States. A comprehensive national CO poisoning surveillance framework is needed to obtain accurate estimates of CO poisoning burden and guide prevention efforts. This article describes the current national CO poisoning surveillance framework and reports the most recent national estimates. Methods. We analyzed mortality data from the National Vital Statistics System multiple cause-of-death file, emergency department (ED) and hospitalization data from the Healthcare Cost and Utilization Projects Nationwide Emergency Department Sample and Nationwide Inpatient Sample, hyperbaric oxygen treatment (HBOT) data from HBOT facilities, exposure data from the National Poison Data System, and CO alarm prevalence data from the American Housing Survey and the National Health Interview Survey. Results. In the United States, 2,631 UNFR CO deaths occurred from 1999 to 2004, an average of 439 deaths annually. In 2007, there were 21,304 (71 per one million population) ED visits and 2,302 (eight per one million population) hospitalizations for confirmed cases of CO poisoning. In 2009, 552 patients received HBOT, and from 2000 to 2009, 68,316 UNFR CO exposures were reported to poison centers. Most nonfatal poisonings were among children (<18 years of age) and females; hospitalizations and deaths occurred more frequently among males and elderly people (>65 years of age). More poisonings occurred during winter months and in the Midwest and Northeast. Conclusions. UNFR CO poisoning poses a significant public health burden. Systematic evaluation of data sources coupled with modification and expansion of the surveillance framework might assist in developing effective prevention strategies.

Cumulative Risk of Guillain–Barré Syndrome Among Vaccinated and Unvaccinated Populations During the 2009 H1N1 Influenza Pandemic

OBJECTIVES We sought to assess risk of Guillain-Barré syndrome (GBS) among influenza A (H1N1) 2009 monovalent (pH1N1) vaccinated and unvaccinated populations at the end of the 2009 pandemic. METHODS We applied GBS surveillance data from a US population catchment area of 45 million from October 15, 2009, through May 31, 2010. GBS cases meeting Brighton Collaboration criteria were included. We calculated the incidence density ratio (IDR) among pH1N1 vaccinated and unvaccinated populations. We also estimated cumulative GBS risk using life table analysis. Additionally, we used vaccine coverage data and census population estimates to calculate denominators. RESULTS There were 392 GBS cases; 64 (16%) occurred after pH1N1vaccination. The vaccinated population had lower average risk (IDR = 0.83, 95% confidence interval = 0.63, 1.08) and lower cumulative risk (6.6 vs 9.2 cases per million persons, P = .012) of GBS. CONCLUSIONS Our findings suggest that at the end of the influenza season cumulative GBS risk was less among the pH1N1vaccinated than the unvaccinated population, suggesting the benefit of vaccination as it relates to GBS. The observed potential protective effect on GBS attributed to vaccination warrants further study.

Recipients of hyperbaric oxygen treatment for carbon monoxide poisoning and exposure circumstances

BACKGROUND Unintentional carbon monoxide poisoning is preventable. Severe cases are often referred for hyperbaric oxygen treatment. To guide prevention efforts and treatment practices, this study provides some of the most detailed current information about patients with carbon monoxide poisoning who have been treated at hyperbaric facilities across the United States and the circumstances surrounding their exposures. This study can help improve efforts to prevent carbon monoxide poisoning and enhance treatment practices. METHODS From August 2008 to January 2010, nonidentifiable, patient-level data were reported by 87 hyperbaric facilities in 39 states via an online reporting system. This reporting system was developed collaboratively by the Undersea and Hyperbaric Medical Society and the Centers for Disease Control and Prevention. RESULTS Among the 864 patients reported to receive hyperbaric oxygen treatment for unintentional, non-fire-related, carbon monoxide poisoning, most of the patients were white men aged between 18 and 44 years. Only 10% of patients reported the presence of a carbon monoxide alarm at their exposure location, and 75% reported being part of a group exposure. Nineteen patients (2%) reported a prior carbon monoxide exposure. About half (55%) of the patients treated were discharged after treatment; 41% were hospitalized. CONCLUSIONS The findings in this report expand the knowledge about patients with carbon monoxide poisoning. These results suggest that prevention efforts, such as educating the public about using carbon monoxide alarms and targeting the most at-risk populations, may help reduce the number of exposures, the number of persons with chronic cognitive sequelae, and the resulting burden on the health care system.

Number of antigens in early childhood vaccines and neuropsychological outcomes at age 7–10 years

Concerns have been raised that children may be receiving too many immunizations under the recommended schedule in the USA. We used a publicly available dataset to evaluate the association between antibody‐stimulating proteins and polysaccharides from early childhood vaccines and neuropsychological outcomes at age 7–10 years.