Biomedical subjects

Margaret A K Ryan

Publications and source records attributed to Margaret A K Ryan.

At least 19 recordsLinked to original sources

PubMed2007

Asthma hospitalizations among US military personnel, 1994 to 2004.

BACKGROUND: Acute asthma attacks strike unpredictably and may lead to hospitalization in otherwise healthy individuals. The burden of asthma hospitalization on the US health care system has greatly interested health care workers, many of whom see the incidence of asthma as increasing. OBJECTIVES: To examine the annual incidence of hospitalization and the frequency of subsequent hospitalization for asthma among all active-duty US military personnel between 1994 and 2004 and to determine demographic and occupational risk factors of asthma hospitalization within this generally healthy US population. METHODS: Annual demographic and occupational data were combined with electronic hospitalization records for patients with a discharge diagnosis of asthma. Using Cox proportional hazard modeling, the authors investigated demographic and occupational risk factors for asthma hospitalization. RESULTS: Women, married persons, health care workers, enlisted personnel, US Army personnel, and older persons were found to have a significantly greater risk of asthma hospitalization. Yearly rates of hospitalization declined from 22.3 per 100,000 persons to 12.6 per 100,000 persons between 1994 and 2004. CONCLUSIONS: Although these data have some limitations, they suggest that the burden of asthma hospitalizations in the large, healthy population of US military personnel has declined during the last decade. The decrease in hospitalization potentially reflects improved outpatient management strategies.

Adolescent↗

PubMed2006

Millennium Cohort: enrollment begins a 21-year contribution to understanding the impact of military service.

OBJECTIVE: In response to health concerns of military members about deployment and other service-related exposures, the Department of Defense (DoD) initiated the largest prospective study ever undertaken in the U.S. military. STUDY DESIGN AND SETTING: The Millennium Cohort uses a phased enrollment strategy to eventually include more than 100,000 U.S. service members who will be followed up through the year 2022, even after leaving military service. Subjects will be linked to DoD and Veterans Affairs databases and surveyed every 3 years to obtain objective and self-reported data on exposures and health outcomes. RESULTS: The first enrollment phase was completed in July 2003 and resulted in 77,047 consenting participants, well representative of both active-duty and Reserve/Guard forces. This report documents the baseline characteristics of these Cohort members, describes traditional, postal, and Web-based enrollment methods; and describes the unique challenges of enrolling, retaining, and following such a large Cohort. CONCLUSION: The Millennium Cohort was successfully launched and is becoming especially relevant, given current deployment and exposure concerns. The Cohort is representative of the U.S. military and promises to provide new insight into the long-term effects of military occupations on health for years to come.

Adolescent↗

PubMed2006

Transmission dynamics and prospective environmental sampling of adenovirus in a military recruit setting.

BACKGROUND: High levels of morbidity caused by adenovirus among US military recruits have returned since the loss of adenovirus vaccines in 1999. The transmission dynamics of adenovirus have never been well understood, which complicates prevention efforts. METHODS: Enrollment and end-of-study samples were obtained and active surveillance for febrile respiratory illnesses (FRIs) was performed for 341 recruits and support personnel. Environmental samples were collected simultaneously. Classic and advanced diagnostic techniques were used. RESULTS: Seventy-nine percent (213/271) of new recruits were seronegative for either adenovirus serotype 4 (Ad-4) or adenovirus serotype 7 (Ad-7). FRI caused by Ad-4 was observed in 25% (67/271) of enrolled recruits, with 100% of them occurring in individuals with enrollment titers <1 : 4. The percentage of recruits seropositive for Ad-4 increased from 34% at enrollment to 97% by the end of the study. Adenovirus was most commonly detected in the environment on pillows, lockers, and rifles. CONCLUSIONS: Potential sources of adenovirus transmission among US military recruits included the presence of adenovirus on surfaces in living quarters and extended pharyngeal viral shedding over the course of several days. The introduction of new recruits, who were still shedding adenovirus, into new training groups was documented. Serological screening could identify susceptible recruits for the optimal use of available vaccines. New high-throughput technologies show promise in providing valuable data for clinical and research applications.

Adenovirus Infections, Human↗

PubMed2006

Vaccine-preventable adenoviral respiratory illness in US military recruits, 1999-2004.

BACKGROUND AND METHODS: The high burden of respiratory infections in military populations is well documented throughout history. The primary pathogen responsible for morbidity among US recruits in training was shown to be adenovirus. Highly efficacious oral vaccines were used for 25 years, but vaccine production ceased in 1996, and available stores were depleted by early 1999. Surveillance for acute febrile respiratory illness was performed at eight military recruit training sites throughout the United States from July 1999 through June 2004 to document rates after loss of the vaccines. Laboratory diagnoses complimented the surveillance efforts. RESULTS: Over the 5 years, nearly 12 million person-weeks were followed and an estimated 110,172 febrile respiratory illness cases and 73,748 adenovirus cases were identified. Rates of illness were highest at the Navy and Air Force training centers, with average annual rates of 1.20 and 1.35 cases per 100 recruit-weeks, respectively. Adenoviral-associated illness rates peaked in weeks 3-5 of training, depending upon service. CONCLUSIONS: The burden of adenoviral illness among US recruit populations has returned to high levels since loss of the vaccines. Restoration of an effective adenovirus vaccine effort within the military is anticipated by 2008, potentially reducing the adenovirus morbidity suffered in this vulnerable population. Efforts to determine the burden of adenovirus and potential benefits of vaccination in civilian populations are being renewed.

Adenovirus Infections, Human↗

PubMed2006

Risky alcohol use, age at onset of drinking, and adverse childhood experiences in young men entering the US Marine Corps.

OBJECTIVE: To examine how childhood experiences relate to risky underage drinking. DESIGN: A survey study of men starting military training between June 11, 2002, and April 5, 2006. Multivariate logistic regression models compared risky drinkers with "all others" or with nonrisky drinkers; excluding nondrinkers. SETTING: Marine Corps Recruit Depot, San Diego, Calif. PARTICIPANTS: Forty-one thousand four hundred eighty-two men aged 18 to 20 years. Main Exposures Age at drinking onset; childhood emotional, physical, and sexual abuse; childhood emotional and physical neglect; and household alcohol abuse, mental illness, domestic violence, or divorce. MAIN OUTCOME MEASURES: Risky drinking identified by scoring responses to 3 questions about alcohol consumption. RESULTS: Of 41,482 young men, 6128 (14.8%) were identified as risky drinkers, 18,693 (45.1%) as nonrisky drinkers, and 16 661 (40.2%) as nondrinkers. Among drinkers, early initiation of alcohol use was strongly associated with risky drinking, with a 5.5-fold risk if age at onset of drinking was 13 years or younger. Other associated factors included tobacco use, rural or small hometown, higher education, motivation to join the military for travel or adventure or to leave problems at home, numerous close friends and relatives, household alcohol abuse or mental illness, and childhood sexual or emotional abuse. When the comparison group included nondrinkers, additional associated factors included childhood physical abuse and domestic violence. CONCLUSIONS: These analyses confirm previous findings on risks for alcohol misuse in young adults and quantify these risks in new, large, multivariable models, adding unique perspective from a population of young Marines. Public health efforts to decrease alcohol misuse may be effectively targeted by prevention of underage alcohol use, tobacco use, and childhood abuse.

Adolescent↗

PubMed2006

A comparison of the postdeployment hospitalization experience of U.S. military personnel following service in the 1991 Gulf War, Southwest Asia after the Gulf War, and Bosnia.

Much attention has been given to the impact of deployment on the health of veterans from the 1991 Gulf War. Whereas increases in self-reported symptoms have been common, no specific exposures have been implicated. Some have suggested that stress from deployment is the chief cause for multisymptom conditions among Gulf War veterans, but comparisons with the health of other recent deployers have not been made. We sought to examine the impact of several large military deployments on hospitalization experience. Hospitalization records were examined for all active duty personnel deployed exclusively to the Gulf War, Southwest Asia after the Gulf War, or Bosnia. Cox's hazard modeling was used to assess time until first post-deployment hospitalization, separation from active duty, or December 31, 2000, whichever occurred first, while controlling for influential covariates and temporal changes. Personnel deployed to Southwest Asia after the 1991 Gulf War were at a slight increased risk for any-cause hospitalization and for 3 of the 14 major diagnostic categories when compared with veterans of the 1991 Gulf War. Personnel deployed to Bosnia were at a decreased risk for any-cause hospitalization and 12 of the 14 major diagnostic categories when compared with Gulf War veterans. These findings do not fully explain the complexity of postdeployment health experiences. Although the risk for hospitalization may be associated with regional deployment, it is unlikely that Gulf War veterans are at greater risk of hospitalization due to a specific exposure-related disease.

Adolescent↗

PubMed2006

The mental health of U.S. military women in combat support occupations.

BACKGROUND: The proportion of women in the U.S. military is increasing, and they are being selected into jobs that are more combat related. However, the mental health effects of working in combat support occupations among military women have not been previously evaluated. METHODS: Active-duty enlisted Navy and Marine Corps women in combat support (n = 10,299) and noncombat support (n = 63,478) occupations were followed for 2 years between January 1, 1994, and August 31, 2001. Hospitalization diagnoses were examined and organized into eight categories of mental disorders; Cox proportional hazards modeling was used to describe these outcomes. RESULTS: Women in combat support occupations were found to be significantly less likely to be hospitalized for a mental disorder than women in all other military occupations. CONCLUSIONS: These results are reassuring but may be confounded by a healthy worker selection effect. Further studies are needed to assess how service in combat support occupations affects the long-term health of U.S. military women.

Adolescent↗

PubMed2006

The Neurocognition Deployment Health Study: a prospective cohort study of Army Soldiers.

Questions remain regarding the effects of military operational deployment on health. The Neurocognition Deployment Health Study addresses several gaps in the deployment health literature, including lack of baseline health data, reliance on subjective measures of exposure and health variables, prolonged intervals between redeployment and health assessments, and lack of a uniform case definition. The Neurocognition Deployment Health Study uses a prospective cohort design to assess neuropsychological outcomes associated with Iraq deployment. Methods incorporate administration of performance-based neuropsychological measures to Army soldiers before and after Iraq deployment and to nondeployed Army Soldiers assessed during comparable periods of garrison duty. Findings should have the potential to delineate neuropsychological outcomes related to combat theater deployment and to identify potential risk and protective factors related to health outcomes.

Cognition Disorders↗

PubMed2006

Mefloquine use and hospitalizations among US service members, 2002-2004.

The safety of mefloquine has not been well described in military populations. This study used standard military databases for mefloquine prescriptions and hospitalizations to investigate mefloquine safety among US service members from 2002 through 2004. Mefloquine-prescribed and deployed personnel (N = 8,858) were compared with two reference groups. The reference groups comprised US service members who were not prescribed mefloquine and resided in Europe or Japan (N = 156,203) or had been otherwise deployed (N = 232,381). In comparison with active-duty US service members residing in Europe or Japan, mefloquine-prescribed service members were at statistically significant decreased hazard for any-cause hospitalization, as well as diseases of the respiratory and digestive systems, musculoskeletal system and connective tissue diseases, injuries and poisonings, ill-defined conditions, and mood disorders. These results suggest there is no association between mefloquine prescriptions and severe health effects, as measured by hospitalizations, across a wide range of outcomes.

Adult↗

PubMed2005

Symptomatic respiratory syncytial virus infection in previously healthy young adults living in a crowded military environment.

BACKGROUND: Respiratory syncytial virus (RSV) infection is a potentially important cause of acute respiratory illness in many populations, including military recruits receiving basic training. Understanding the full impact of RSV infection is challenging because of difficulties in diagnosis and the limitations of past epidemiologic studies. In this study, we set out to determine the prevalence and clinical characteristics of RSV infection and infection caused by other common viral agents in a population of previously healthy young adults, namely, military recruits receiving basic training. METHODS: In addition to standard viral culture techniques, we employed serologic testing and a recently described, novel, highly sensitive real-time PCR and a molecular beacon probe assay for the detection of RSV infection. RESULTS: Among 256 military trainees with respiratory symptoms, RSV infection was identified in 11% by means of serologic testing and real-time PCR. Viral culture identified adenovirus in 48% of symptomatic recruits, influenza viruses in 11%, parainfluenza virus 3 in 3%, and enterovirus in <1%. The majority of recruits with RSV infection experienced a nonproductive cough, sore throat, and nasal congestion, and almost half reported symptoms of wheeze or shortness of breath. Almost all (94%) of the recruits lost > or =1 day(s) from training because of illness. CONCLUSIONS: This study demonstrates the challenges of diagnosis and clinical significance of RSV infection in symptomatic young adults. RSV may account for 11% of clinically important respiratory illnesses in this population, which is as much as 25% of previously undiagnosed illness. These results have implications for treatment and prevention of RSV in young adults.

Adolescent↗

PubMed2005

Fatal meningitis in a previously healthy young adult caused by Streptococcus pneumoniae serotype 38: an emerging serotype?

BACKGROUND: In December 2001, a fatal case of pneumococcal meningitis in a Marine Corps recruit was identified. As pneumococcal vaccine usage in recruit populations is being considered, an investigation was initiated into the causative serotype. CASE PRESENTATION: Traditional and molecular methods were utilized to determine the serotype of the infecting pneumococcus. The pneumococcal isolate was identified as serotype 38 (PS38), a serotype not covered by current vaccine formulations. The global significance of this serotype was explored in the medical literature, and found to be a rare but recognized cause of carriage and invasive disease. CONCLUSION: The potential of PS38 to cause severe disease is documented in this report. Current literature does not support the hypothesis that this serotype is increasing in incidence. However, as we monitor the changing epidemiology of pneumococcal illness in the US in this conjugate era, PS38 might find a more prominent and concerning niche as a replacement serotype.

Adolescent↗

PubMed2005

Effectiveness of the 2003-2004 influenza vaccine among U.S. military basic trainees: a year of suboptimal match between vaccine and circulating strain.

Effectiveness of the 2003-2004 influenza vaccine was evaluated at five military basic training centers throughout the United States. Data from surveillance conducted in December and January 2003-2004 in this highly vaccinated population were evaluated. During this period, 10.6% (37/350) of specimens were positive for influenza A. A 14-day period after vaccination was considered the period prior to immune protection; vaccine effectiveness (VE) was calculated based on febrile respiratory illness presentation and laboratory confirmation of influenza before or after this 14-day period. Thirty-two cases presented within 14 days of vaccination, and five cases presented beyond 14 days from vaccination. VE in this population was estimated to be 94.4% for laboratory-confirmed influenza. In contrast, VE was only 13.9% for influenza-like illness (ILI) without a laboratory confirmation.

Adult↗

PubMed2005

Assessing the potential health impact of the 1991 Gulf War on Saudi Arabian National Guard soldiers.

BACKGROUND: There has been considerable publicity that the 1991 Gulf War may have caused a wide array of health problems in military personnel. Although post-war health outcomes have been studied in US, British, Canadian, Danish, and other deployed troops, this issue has not been previously evaluated in coalition forces native to the Gulf region. METHODS: A collaborative team of US and Saudi health researchers was assembled, data sources evaluated, and hospitalizations among Saudi Arabian National Guard (SANG) soldiers between 1991 and 1999 analysed. Multivariate modelling was used to evaluate differences between 8342 soldiers exposed to combat at Al Khafji and a comparison group of 7270 soldiers in the Riyadh area. RESULTS: Among 15 612 SANG soldiers, we identified 148 with at least one hospitalization over the 9 years following the war. The adjusted rate of hospitalization was higher in the combat-exposed group (risk ratio (RR) = 1.80, 95% confidence interval (CI) 1.25-2.59). No unusual patterns of diagnoses were found and, because the overall number of hospitalizations was low, the absolute difference in risk was found to be very small. CONCLUSIONS: This is the first reported epidemiological investigation of post-war hospitalizations among coalition forces native to the Gulf region that participated in the 1991 Gulf War. A very small increase in hospitalizations was identified in SANG soldiers exposed to combat at Al Khafji. However, because of data limitations, the clinical relevance of this finding should be interpreted with caution. Future collaborative studies to better understand the health effects of deployment should be encouraged.

Adolescent↗

PubMed2005

Saudi Arabia-United States collaboration in health research: a formula for success.

The aim of this article is to share our experiences from an international collaborative effort to study health outcomes among Saudi Arabian National Guard (SANG) soldiers following the 1991 Gulf War. By paying particular attention to distinct social and religious customs, geopolitical differences, and unique aspects of the health care system, we achieved a successful international collaboration in health research.

Cultural Characteristics↗

PubMed2005

PCR analysis of egyptian respiratory adenovirus isolates, including identification of species, serotypes, and coinfections.

Eighty-eight adenovirus (Ad) isolates and associated clinical data were collected from walk-in patients with influenza-like illness in Egypt during routine influenza surveillance from 1999 through 2002. Respiratory Ad distributions are geographically variable, and serotype prevalence has not been previously characterized in this region. Serotype identity is clinically relevant because it predicts vaccine efficacy and correlates strongly with both clinical presentation and epidemiological pattern. Species and serotype identities were determined using several well-validated multiplex PCR protocols culled from the literature and supplemented with a few novel primer sets designed to identify rare types. The isolates included common species B1 serotypes (Ad3 and Ad7), common species C serotypes (Ad1, Ad2, and Ad5), the less common species B2 serotype Ad11, and three isolates of the rare species B1 serotype Ad16. Two isolates that appear to be variant Ad16 were also identified. Fifteen coinfections of multiple adenoviral types, primarily AdB/AdC and Ad3/Ad7 dual infections, were detected. The majority of these were verified using redundant PCR tests targeted at multiple genes. PCR is able to resolve coinfections, in contrast to traditional serum neutralization tests. PCR is also comparatively rapid and requires very little equipment. Application of the method allowed an inclusive determination of the serotypes found in the Egyptian respiratory sample set and demonstrated that coinfections are common and may play a previously unrecognized role in adenovirus pathogenesis, evolution, and epidemiology. In particular, coinfections may influence adenoviral evolution, as interserotypic recombination has been identified as a source of emerging strains.

Adenovirus Infections, Human↗

PubMed2004

An outbreak of conjunctivitis due to a novel unencapsulated Streptococcus pneumoniae among military trainees.

BACKGROUND: Bacterial conjunctivitis usually occurs as sporadic cases; outbreaks are uncommon and usually are associated with school campuses. We report an outbreak of Streptococcus pneumoniae conjunctivitis at a military training facility. METHODS: An outbreak investigation was done. Each case of conjunctivitis was evaluated with an assessment tool including demographic and clinical data. Conjunctival swabs were obtained. Pneumococci underwent standard testing, including serotyping with the Quellung reaction, capsular staining, and multilocus sequence typing. Sequence types were compared with previous reported outbreak strains by construction of dendrograms. Carriage rates of S. pneumoniae were determined among previously undiagnosed case patients with conjunctivitis, and a case-control study was performed. Control measures included education to increase hand washing, distribution of alcohol-based hand gel, and prompt treatment of patients with conjunctivitis. RESULTS: During a 6-week period, 92 cases of conjunctivitis occurred among 3500 persons, with an attack rate of 1.75 cases per 100 person-months. Eighty cases (87%) were due to S. pneumoniae; 45 (49%) were confirmed, and 35 (38%) were probable. Ten percent of recruits surveyed carried the outbreak strain. Twenty-two percent self-reported symptoms consistent with conjunctivitis during the outbreak period; sharing washcloths was associated with conjunctivitis (odds ratio, 11.7; P=.03). The causative organism was resistant to azithromycin but susceptible to telithromycin. The outbreak strain was an unencapsulated S. pneumoniae that has not been previously described; it was most closely related to the sequence type causing the Dartmouth College (Hanover, NH) outbreak of conjunctivitis in 2002. CONCLUSIONS: We report a conjunctivitis outbreak among military trainees caused by a novel, unencapsulated strain of S. pneumoniae.

Adolescent↗

PubMed2004

Benefits and harms of doxycycline treatment for Gulf War veterans' illnesses: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: It has been hypothesized that certain Mycoplasma species may cause Gulf War veterans' illnesses (GWVIs), chronic diseases characterized by pain, fatigue, and cognitive symptoms, and that affected patients may benefit from doxycycline treatment. OBJECTIVE: To determine whether a 12-month course of doxycycline improves functional status in Gulf War veterans with GWVIs. DESIGN: A randomized, double-blind, placebo-controlled clinical trial with 12 months of treatment and 6 additional months of follow-up. SETTING: 26 U.S. Department of Veterans Affairs and 2 U.S. Department of Defense medical centers. PARTICIPANTS: 491 deployed Gulf War veterans with GWVIs and detectable Mycoplasma DNA in the blood. INTERVENTION: Doxycycline, 200 mg, or matching placebo daily for 12 months. MEASUREMENTS: The primary outcome was the proportion of participants who improved more than 7 units on the Physical Component Summary score of the Veterans Short Form-36 General Health Survey 12 months after randomization. Secondary outcomes were measures of pain, fatigue, and cognitive function and change in positivity for Mycoplasma species at 6, 12, and 18 months after randomization. RESULTS: No statistically significant differences were found between the doxycycline and placebo groups for the primary outcome measure (43 of 238 participants [18.1%] vs. 42 of 243 participants [17.3%]; difference, 0.8 percentage point [95% CI, -6.5 to 8.0 percentage points]; P > 0.2) or for secondary outcome measures at 1 year. In addition, possible differences in outcomes at 3 and 6 months were not apparent at 9 or 18 months. Participants in the doxycycline group had a higher incidence of nausea and photosensitivity. LIMITATIONS: Adherence to treatment after 6 months was poor. CONCLUSION: Long-term treatment with doxycycline did not improve outcomes of GWVIs at 1 year.

Adult↗

PubMed2004

In-theater hospitalizations of US and allied personnel during the 1991 Gulf War.

The postwar morbidity of Gulf War veterans has been closely examined. However, data have not been available to evaluate morbidity suffered during the 1991 Gulf War. In this report, the authors examine archived records of hospitalizations in US military facilities in the Kuwaiti theater of operations or those medically evacuated to facilities in Europe. Using multivariable logistic regression modeling, the authors determined that service personnel at greatest odds for "in-theater" hospitalization were enlisted, female, White, Reservist, Army, and health care workers. No increase in odds was observed for oil well fire smoke exposure or possible exposure to the nerve agent hazard areas. Although these data may be incomplete, they represent the best-known data reflecting in-theater hospitalizations during the Gulf War of 1991 and show remarkable similarities in risk factors to those for postwar hospitalization.

Adolescent↗