Chronic multisystem illness among Gulf War veterans.
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Humans↗
Biomedical subjects
R W Haley
Publications and source records attributed to R W Haley.
Association of low PON1 type Q (type A) arylesterase activity with neurologic symptom complexes in Gulf War veterans.
Previously Haley et al. described six possible syndromes identified by factor analysis of symptoms in Gulf War veterans and demonstrated that veterans with these symptom complexes were more neurologically impaired than age-sex-education-matched well controls. They also uncovered strong associations (relative risks 4-8) suggesting that these symptom complexes were related to wartime exposure to combinations of organophosphate pesticides, chemical nerve agents, high concentration DEET insect repellant, and symptoms of advanced acute toxicity after taking pyridostigmine. Here we have shown that compared to controls, ill veterans with the neurologic symptom complexes were more likely to have the R allele (heterozygous QR or homozygous R) than to be homozygous Q for the paraoxonase/arylesterase 1 (PON1) gene. Moreover, low activity of the PON1 type Q (Gln192, formerly designated type A) arylesterase allozyme distinguished ill veterans from controls better than just the PON1 genotype or the activity levels of the type R (Arg192, formerly designated type B) arylesterase allozyme, total arylesterase, total paraoxonase, or butyrylcholinesterase. A history of advanced acute toxicity after taking pyridostigmine was also correlated with low PON1 type Q arylesterase activity. Type Q is the allozyme of paraoxonase/arylesterase that most efficiently hydrolyzes several organophosphates including sarin, soman, and diazinon. These findings further support the proposal that neurologic symptoms in some Gulf War veterans were caused by environmental chemical exposures.
Adult↗
Point: bias from the "healthy-warrior effect" and unequal follow-up in three government studies of health effects of the Gulf War.
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Bias↗
Is Gulf War syndrome due to stress? The evidence reexamined.
Medical policy-makers have concluded that stress from wartime trauma and deployment constitutes an important cause of the chronic physical symptoms observed in US veterans who served in the Persian Gulf War. The author reviewed scientific articles from peer-reviewed journals referenced in the final report of the Presidential Advisory Committee on Gulf War Veterans' illnesses and conducted a MEDLINE literature search. All reported prevalence rates of post-traumatic stress disorder (PTSD) in Gulf War veterans were defined by critical cutpoints on psychometric scales constructed by summing veterans' responses on standardized symptom questionnaires rather than by clinical psychiatric interviews. Observed PTSD rates varied from 0% to 36% (mean, 9%). Correcting for measurement errors with previously determined values of the sensitivity (range 0.77 to 0.96) and specificity (range 0.62 to 0.89) of the psychometric tests yielded estimated true PTSD rates of 0% for 18 of the 20 reported rates. Mean scores on the Mississippi PTSD scale in all subgroups of Gulf War veterans were within the range of values for well-adjusted Vietnam veterans (50-89) and far below that of Vietnam veterans with psychiatrically confirmed PTSD (120-140). Most PTSD and "stress-related symptoms" reported in studies of Gulf War veterans appear to represent false-positive errors of measurement reflecting nonspecific symptoms of other conditions.
Diagnosis, Differential↗
Is there a Gulf War Syndrome? Searching for syndromes by factor analysis of symptoms.
OBJECTIVE: To search for syndromes in Persian Gulf War veterans. PARTICIPANTS: Two hundred forty-nine (41%) of the 606 Gulf War veterans of the Twenty-fourth Reserve Naval Mobile Construction Battalion living in 5 southeastern states participated; 145 (58%) had retired from service, and the rest were still serving in the battalion. DESIGN: Participants completed a standardized survey booklet measuring the anatomical distributions or characteristics of each symptom, a booklet measuring wartime exposures, and a standard psychological personality assessment inventory. Two-stage factor analysis was used to disentangle ambiguous symptoms and identify syndromes. MAIN OUTCOME MEASURES: Factor analysis-derived syndromes. RESULTS: Of 249 participants, 175 (70%) reported having had serious health problems that most attributed to the war, and 74 (30%) reported no serious health problems. Principal factor analysis yielded 6 syndrome factors, explaining 71% of the variance. Dichotomized syndrome indicators identified the syndromes in 63 veterans (25%). Syndromes 1 ("impaired cognition," characterized by problems with attention, memory, and reasoning, as well as insomnia, depression, daytime sleepiness, and headaches), 2 ("confusion-ataxia," characterized by problems with thinking, disorientation, balance disturbances, vertigo, and impotence), and 3 ("arthro-myo-neuropathy," characterized by joint and muscle pains, muscle fatigue, difficulty lifting, and extremity paresthesias) represented strongly clustered symptoms; whereas, syndromes 4 ("phobia-apraxia"), 5 ("fever-adenopathy"), and 6 ("weakness-incontinence") involved weaker clustering and mostly overlapped syndromes 2 and 3. Veterans with syndrome 2 were 12.5 times (95% confidence interval, 3.5-44.8) more likely to be unemployed than those with no health problems. A psychological profile, found in 48.4% of those with the syndromes, differed from posttraumatic stress disorder, depression, somatoform disorder, and malingering. CONCLUSION: These findings support the hypothesis that clusters of symptoms of many Gulf War veterans represent discrete factor analysis-derived syndromes that appear to reflect a spectrum of neurologic injury involving the central, peripheral, and autonomic nervous systems.
Adult↗
Evaluation of neurologic function in Gulf War veterans. A blinded case-control study.
OBJECTIVE: To determine whether Gulf War-related illnesses are associated with central or peripheral nervous system dysfunction. DESIGN: Nested case-control study. PARTICIPANTS: Twenty-three veterans with factor analysis-derived syndromes (the cases), 10 well veterans deployed to the Gulf War (the deployed controls), and 10 well veterans not deployed to the Gulf War (the nondeployed controls). METHOD: With investigators blinded to group identities, participants underwent objective neurophysiological, audiovestibular, neuroradiological, neuropsychological, and blood tests. MAIN OUTCOME MEASURES: Evidence of neurologic dysfunction. RESULTS: Compared with the 20 controls, the 23 cases had significantly more neuropsychological evidence of brain dysfunction on the Halstead Impairment Index (P=.01), greater interside asymmetry of the wave I to wave III interpeak latency of brain stem auditory evoked potentials (P=.02), greater interocular asymmetry of nystagmic velocity on rotational testing, increased asymmetry of saccadic velocity (P=.04), more prolonged interpeak latency of the lumbar-to-cerebral peaks on posterior tibial somatosensory evoked potentials (on right side, P=.03, and on the left side, P=.005), and diminished nystagmic velocity after caloric stimulation bilaterally (P values range from .02 to .04). Cases (n=5) with syndrome 1 ("impaired cognition") were the most impaired on brain stem auditory evoked potentials (P=.005); those (n=13) with syndrome 2 ("confusion-ataxia") were the most impaired on the Halstead Impairment Index (P=.006), rotational testing (P=.01), asymmetry of saccadic velocity (P=.03), and somatosensory evoked potentials (P< or =.01); and those (n=5) with syndrome 3 ("arthro-myo-neuropathy") were the most impaired on caloric stimulation (P< or =.01). CONCLUSIONS: The 3 factor-derived syndromes identified among Gulf War veterans appear to represent variants of a generalized injury to the nervous system.
Adult↗
Self-reported exposure to neurotoxic chemical combinations in the Gulf War. A cross-sectional epidemiologic study.
OBJECTIVE: To identify risk factors of factor analysis-derived Gulf War-related syndromes. DESIGN: A cross-sectional survey. PARTICIPANTS: A total of 249 Gulf War veterans from the Twenty-fourth Reserve Naval Mobile Construction Battalion. DATA COLLECTION: Participants completed standardized booklets measuring self-reported wartime exposures and present symptoms. MAIN OUTCOME MEASURES: Associations of factor analysis-derived syndromes with risk factors for chemical interactions that inhibit butyrylcholinesterase and neuropathy target esterase. RESULTS: Risk of syndrome 1 ("impaired cognition") was greater in veterans who reported wearing flea collars during the war (5 of 20, 25%) than in those who never wore them (7 of 229, 3%; relative risk [RR], 8.7; 95% confidence interval [CI], 3.0-24.7; P<.001). Risk of syndrome 2 ("confusion-ataxia") increased with a scale of advanced adverse effects from pyridostigmine bromide (chi2 for trend, P<.001), was greater among veterans who believed they had been involved in chemical weapons exposure (18 of 108, 17%) than in those who did not (3 of 141, 2%; RR, 7.8; 95% CI, 2.3-25.9; P<.001), and was increased in veterans who had been in a sector of far northeastern Saudi Arabia on the fourth day of the air war (6 of 21, 29%) than in those who had not been (15 of 228, 7%; RR, 4.3; 95% CI, 1.9-10.0; P=.004). Effects of perceived chemical weapons exposure and advanced adverse effects from pyridostigmine were synergistic (Rothman S, 5.3; 95% CI, 1.04-26.7). Risk of syndrome 3 ("arthro-myo-neuropathy") increased with an index of frequency and amount of government-issued insect repellent containing 75% DEET (N,N-diethyl-m-toluamide) in ethanol applied during the war (chi2 for trend, P<.001) and with advanced adverse effects from pyridostigmine (chi2 for trend, P<.001). CONCLUSION: Some Gulf War veterans may have delayed, chronic neurotoxic syndromes from wartime exposure to combinations of chemicals that inhibit butyrylcholinesterase and neuropathy target esterase.
Adult↗
Neuropsychological correlates of Gulf War syndrome.
As part of a comprehensive multispecialty project, the present study reports on the neurocognitive and psychological function of veterans who report Persian Gulf War-related symptoms. The neuropsychological and psychological performances of 26 ill Gulf War veterans were compared to 20 well veterans from the same military unit. Neurocognitive functions assessed included intelligence, abstraction and problem-solving, attention and concentration, memory and learning, language and visual-spatial function, and sensorimotor abilities. Psychological function was measured by self-report questionnaires. Results indicated global and consistently poorer intellectual and neurocognitive function among the ill veterans compared to the control veterans. A generalized pattern of neuropsychological deficit was evident for the ill veterans. Psychological profiles of the ill veterans were similar to those in general medical patients. Based on these findings and results from the multispecialty investigation, we conclude that some of the ill veterans have experienced neurotoxic injury resulting in chronic neuropsychological impairment that is related to their service in the Persian Gulf War.
Journal Article↗
The scientific basis for using surveillance and risk factor data to reduce nosocomial infection rates.
Research over the past 20 years has demonstrated that an active programme of surveillance with feedback of surgical wound infection rates to surgeons can reduce subsequent rates by 30-40%. For surveillance data and feedback to be meaningful and influential, however, certain rigorous methodological principles must be observed. First, surveillance data must be collected in an accurate, efficient and confidential manner. This requires written definitions of infection, regular clinical case-finding, post-discharge follow up for short-staying patients, and computer storage, analysis and reporting of the data in coded form that does not publicly identify individuals. Second, the variation in intrinsic risk of the patients of the various surgeons must be controlled for by stratifying the final infection rates on a multivariate risk index, which combines the traditional classes of wound contamination with measures of intrinsic patient susceptibility. This can be accomplished with a relatively small commitment of time by the Infection Control Nurse with the aid of sophisticated computer software that is now available.
Confidentiality↗
Eradication of endemic methicillin-resistant Staphylococcus aureus infections from a neonatal intensive care unit.
To control infections with endemic methicillin-resistant Staphylococcus aureus (MRSA) in a neonatal intensive care unit (NICU), triple dye was applied to the umbilical cords of infants in the intermediate-care but not the intensive-care area. The rate of MRSA infection, adjusted for time and intensity of care, decreased in the intermediate-care area (rate ratio, 0.35; 95% confidence interval [CI], 0.14-0.87; P < .01) but not in the intensive-care area (rate ratio, 0.92; 95% CI, 0.41-2.24; P = .48). After 22 months, the rate increased in both areas (Mantel-Haenszel rate ratio, 1.7; 95% CI, 1.0-2.8; P < .05) after overcrowding and understaffing increased. After temporary reduction of overcrowding and understaffing, extension of triple dye use to the intensive-care area and dedication of an infection control nurse to the NICU, MRSA colonization and infection rates decreased to near zero in both areas (infection rate ratios, 0.09 and 0.11, respectively; P < .005). The endemic MRSA strain, identified by pulsed-field gel electrophoresis, was eradicated.
Birth Weight↗
Initial STD visits by adolescent females, Dallas County, Texas.
Sexually active adolescents are at high risk for unintended pregnancy and sexually transmitted diseases. We identified a cohort of 6089 women aged 13 to 21 years who in 1985 either delivered an infant at Parkland Hospital (3154) or used the outpatient clinics (2935). We reviewed those records and others in the Dallas County sexually transmitted disease (STD) clinic for the period 1983 through 1988 to determine the prevalence of visits to the Dallas County STD clinic by pregnant and nonpregnant adolescents, STD diagnoses at initial visit, whether STD visits and diagnoses varied by pregnancy status or ethnic background, and how the women were referred to the STD clinic. Similar percentages of nonpregnant (13%) and pregnant (11%) women had an STD visit, and most adolescents who visited the STD clinic had an STD diagnosis made. Gonorrhea and syphilis were the STDs diagnosed most frequently in both pregnant and nonpregnant adolescents. Regardless of pregnancy status, black adolescents were 7.3 times more likely to have an STD visit. Referral by a sexual partner was the second most common reason that adolescents sought STD care. Our study provides only minimal estimates of STDs among adolescents but indicates STDs, regardless of pregnancy status, are a more common medical problem than has been reported previously. Referral by sexual partners may be an important way to reach adolescents at risk for STDs.
Adolescent↗
The necessity and efficiency of wound surveillance after discharge.
A surgical wound surveillance program followed up 16,453 consecutive patients from 1983 through 1988. Patients were followed up for 30 days after operation, and 516 (35%) of the surgical wound infections first became manifest after discharge. In-hospital surveillance alone would have estimated the surgical wound infection rate to be 5.8% when the true rate was 8.9%. Infections that occurred after discharge were more likely in clean operations, in shorter operations, in obese patients, and in nonalcoholic patients. The probability that infections would begin after discharge was inversely associated with the duration of postoperative stay in the hospital. Postdischarge follow-up of patients who previously have undergone surgery is necessary to avoid underestimated of the infection rates and biases related to known risk factors. The most efficient time to survey patients appears to be at 21 days after the operation, at which time 90% of surgical wound infections have occurred.
Alcoholism↗
Measuring the costs of nosocomial infections: methods for estimating economic burden on the hospital.
To compete more effectively for resources, it is increasingly important for infection control practitioners to estimate the costs of nosocomial infections and the amount of money their infection control programs save the hospital. Studies on costs should estimate both extra length of stay and extra costs attributable to infectious complications. Cost estimates should either adjust charges by a cost to charge ratio, which is relatively easy, or estimate hospital costs directly by detailed cost-accounting, which is comparatively more difficult. If there is insufficient time to measure costs concurrently in every infected patient, comparative studies can be done by comparing infected and uninfected patients matched on characteristics that control for the preexisting differences between them. Diagnosis-related groups and the number of diagnoses appear to be useful matching variables because they are strongly associated with both nosocomial infection and length of stay. The final results should be expressed as either potential or actual savings to the hospital, depending on whether significant reductions in nosocomial infection rates have been achieved.
Cost Savings↗
Nosocomial infections in surgical patients: developing valid measures of intrinsic patient risk.
For surgeons or hospitals to compare their rates of wound infection meaningfully, the analysis must first control for the mix of intrinsic infection risk of their patients. Research over the past century has led to the development of several intrinsic risk indexes that can be used to stratify the wound infection rates so that valid comparisons can be made within risk strata. For an intrinsic risk index to be useful for comparing rates, it must control for all of the important intrinsic risk constructs; merely being statistically associated with infection rates does not ensure that a risk index will be useful. Understanding how a risk index can be both parsimonious and comprehensive requires consideration of the competing principles of multicollinearity and orthogonality. Various techniques of multivariate analysis are used to develop multivariate risk indexes, but the success of the process depends on having all of the important orthogonal risk constructs represented in the pool of predictor variables available for the analysis, either directly by variables in the pool or by demonstrated multicollinearity. Despite recent advances in risk measurement, many important questions remain.
Cross Infection↗
Methicillin-resistant Staphylococcus aureus: do we just have to live with it?
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Cross Infection↗
Tuberculosis epidemic among hospital personnel.
Six employees of the emergency department at Parkland Memorial Hospital developed active tuberculosis in 1983-1984. Five of the cases occurred four to 12 months after exposure to the index case, a patient with severe cavitary tuberculosis seen in the emergency department in April 1983. One resident physician developed cavitary disease after exposure to this patient. An additional employee case may have resulted from transmission from one of the initial employee cases. One immunocompromised patient may have acquired tuberculosis as a result of exposure to the index case. In addition, the tuberculin skin tests of at least 47 employees exposed to the index case converted from negative to positive. Of 112 previously tuberculin-negative emergency department employees who were tested in October 1983, 16 developed positive skin tests, including the 5 employees with active disease. Fifteen of these new positives had worked on April 7, 1983, while the index case was in the emergency department (X2 = 20.6, P less than 0.001). Factors related to the genesis of the epidemic included the disease characteristics in the index case and the recirculation of air in the emergency department. This investigation indicates that city-county hospital emergency department employees should be screened at least twice a year for evidence of tuberculosis and that the employee health services of such hospitals should regard the surveillance of tuberculosis infection among personnel at a high-priority level.
Aged↗
Surgical wound infections.
At the last meeting of the SURGIKOS Operating Room/Infection Control Combined Advisory Panel, guest speakers reviewed current thinking and practices that have an impact on surgical wound infections. Presentation topics included the role of the CDC, nursing and classification systems in controlling wound infections; cost effective epidemiologic methods of reducing infections; and outcomes of surgical wound infection prevention practices deemed critical by the Joint Commission on Accreditation of Healthcare Organizations. The following is a brief overview of the presentations that guided panel discussions on these topics.
Antisepsis↗
Does infection control control infection?
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Centers for Disease Control and Prevention, U.S.↗