Invasive group A streptococcal infection and nonsteroidal antiinflammatory drug use among children with primary varicella.

OBJECTIONS: To test the hypothesis that nonsteroidal antiinflammatory drug use increases the risk of necrotizing soft tissue infections and, secondarily, all invasive group A streptococcal (GAS) infections in children with primary varicella infection. METHODS: We conducted a prospective, multicenter case-control study among children <19 years old. Cases were children hospitalized with primary varicella complicated by invasive GAS infection or necrotizing soft tissue infection identified by a network of 45 pediatric infectious disease specialists located throughout the United States. Controls were children with uncomplicated primary varicella residing in the same communities as the cases. Data on medical history, clinical features of the varicella infection, signs and symptoms of infectious complications, and medication use were collected by structured telephone interviews. Univariate and multivariate matched odds ratios were calculated using conditional logistic regression. RESULTS: Between June 1996 and September 1998, 52 cases of invasive GAS infection, including 21 with necrotizing soft tissue infection, and 172 controls with uncomplicated primary varicella were enrolled. Risk of invasive GAS infection was increased among children who were nonwhite (multivariate odds ratio [OR] 3.8, 95% confidence interval [CI]: 1.4-11), living in low-income households (OR 5.1, 95% CI: 1.7-15), exposed to varicella at home (OR 6.4, 95% CI: 2.6-16), or had a persistent high fever (OR 9.6, 95% CI: 2.8-33). Antipyretic regimen was associated with several measures of varicella illness severity among the controls. The risk of necrotizing soft tissue infection was not associated with the use of ibuprofen before the development of signs or symptoms of this complication (OR 1.3, 95% CI: 0.33-5.3). Risk of any invasive GAS infection was increased among children who had received ibuprofen (OR 3.9, 95% CI: 1.3-12), but not acetaminophen (OR 1.2, 95% CI: 0.50-3.0). However, there was no evidence of increasing risk with increasing duration of ibuprofen use. Subgroup analyses revealed that the risk of invasive GAS infection was increased only among children who had received both acetaminophen and ibuprofen. CONCLUSIONS: These data do not support the hypothesis that nonsteroidal antiinflammatory drugs, or ibuprofen in particular, increase the risk of necrotizing GAS infections. A statistically significant association was observed between nonnecrotizing invasive GAS infection and ibuprofen use; however, because of potential confounding, the meaning of this unexpected result is unclear. Nonetheless, these data suggest that parents use ibuprofen or ibuprofen together with acetaminophen to treat high fever and severe illness, which seems to identify children at high risk for invasive GAS infection.

Vasectomy and prostate cancer.

PURPOSE: Vasectomy has been associated with an increased risk of prostate cancer in some previous studies but not in others. We evaluated the association in a population based, case control study in Massachusetts. MATERIALS AND METHODS: Included in our study were 1,216 patients younger than 70 years with newly diagnosed prostate cancer and 1,400 controls with no history of prostate cancer who were matched to patients by age and town of residence. Data on vasectomy and potential confounding factors were obtained by telephone interview, and confounding was controlled by conditional logistic regression analysis. RESULTS: Overall 16% of patients and 15% of controls had undergone vasectomy. Compared with no vasectomy the odds ratio for ever having undergone vasectomy was 1.0 (95% confidence interval [CI] 0.8 to 1.3), which did not vary significantly by age at or interval since vasectomy. In men who reported urological symptoms and those without symptoms the odds ratio was 0.9 (95% CI 0.7 to 1.2) and 1.4 (1.0 to 1.9), respectively. In men younger than 55 years and those 55 years old or older at diagnosis of prostate cancer the odds ratio was 1.9 (95% CI 1.2 to 3.2) and 1.0 (0.8 to 1.3), respectively [corrected]. In the younger men with stages A or B and C or D disease the odds ratio was 2.3 (95% CI 1.2 to 4.3) and 1.3 (0.5 to 3.5), respectively. CONCLUSIONS: Our findings do not support the hypothesis that vasectomy increases the risk of prostate cancer in men older than 55 years. Further study is needed to determine whether the observed association between vasectomy and prostate cancer in men younger than 55 years is due to chance, detection bias or a causal effect.

Changes in sleep position during infancy: a prospective longitudinal assessment.

CONTEXT: Prone sleeping by infants has been associated with an increased risk of sudden infant death syndrome. OBJECTIVE: To document the prevalence of and identify risk factors for prone sleeping during the first 6 months of life. DESIGN: Prospective cohort study. SETTING: Eastern Massachusetts and northwest Ohio. STUDY PARTICIPANTS: A total of 7796 mothers of infants weighing 2500 g or more at birth. MAIN OUTCOME MEASURES: Maternal and infant characteristics related to prone sleeping at 1 month and 3 months of age. RESULTS: Between 1 month and 3 months of age, prone sleeping increased from 18% to 29%. At 1 month, prone sleeping was associated with the following maternal characteristics: non-Hispanic black or Hispanic race/ethnicity, younger age, less education, and higher parity. At 3 months, switching from nonprone to prone position was associated with mother's race/ethnicity of non-Hispanic black (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.2-2.3) or Hispanic (OR, 1.5; 95% CI, 1.1-2.2); younger maternal age (compared with mothers >34 years: 18-24 years, OR, 1.6; 95% CI, 1.2-2.2; <18 years, OR, 2.2; 95% CI, 1.2-4.3); increasing parity (compared with 1 child: 2 children, OR, 1.5; 95% CI, 1.2-1.8; > or =3 children, OR, 1.7; 95% CI, 1.4-2.2); and infant sex (male sex, OR, 1.4; 95% CI, 1.2-1.7). CONCLUSIONS: If infant sleeping practices in the study communities are representative of practices throughout the United States, a substantial number of infants who slept nonprone at 1 month sleep prone at 3 months.

Calcium channel blocker use and the risk of prostate cancer.

A recent study suggested that the risk of all cancers, including prostate cancer, is increased by the use of calcium channel blockers. The objective of this study was to determine whether prostate cancer is associated with calcium channel blocker use. A case-control study was conducted in Massachusetts using cases diagnosed from December 1992 through February 1995. Cases were men identified by tumor registrars who were less than 70 years old with newly diagnosed prostate cancer. Controls were men with no history of prostate cancer or symptoms of undiagnosed prostate cancer, and were matched to the cases on precinct of residence and half-decade of age. A total of 1217 cases of prostate cancer and 1400 community controls are included in this analysis. Data were collected by telephone interview. Multiple logistic regression was used to estimate relative risks for calcium channel blockers use while controlling for confounding. The relative risk for prostate cancer for any use of calcium channel blockers relative to nonuse was 1.2 (95% confidence interval [CI], 0.9-1.5). There was no evidence of a trend according to duration of use. When the analysis was confined to symptomatic men, the relative risk estimate was 1.1 (0.8-1.4) overall and 1.2 (0.8-1.7) among those aged 65 to 69 years. Relative risk estimates for the use of other classes of antihypertensive drugs among symptomatic men were close to 1.0; the corresponding estimates among asymptomatic men were generally further from 1.0. These findings suggest that calcium channel blockers do not increase the risk of prostate cancer. The differences in the relative risk estimates between symptomatic and asymptomatic men are compatible with detection bias. Because of the widespread use of Prostate-Specific Antigen testing for early detection of prostate cancer, potential detection bias needs to be considered in future studies of prostate cancer.

Cancer risk and residential proximity to cranberry cultivation in Massachusetts.

OBJECTIVES: This study evaluated the relationship between cancer risk and residential proximity to cranberry cultivation. METHODS: A population-based case-control study was conducted. Cases, diagnosed during 1983 through 1986 among residents of the Upper Cape Cod area of Massachusetts, involved incident cancers of the lung (n = 252), breast (n = 265), colon-rectum (n = 326), bladder (n = 63), kidney (n = 35), pancreas (n = 37), and brain (n = 37), along with leukemia (n = 35). Control subjects were randomly selected from among telephone subscribers (n = 184), Medicare beneficiaries (n = 464), and deceased individuals (n = 723). RESULTS: No meaningful increases in risk were seen for any of the cancer sites except for the brain. When latency was considered, subjects who had ever lived within 2600 ft (780 m) of a cranberry bog had a twofold increased risk of brain cancer overall (95% confidence interval [CI] = 0.8, 4.9) and a 6.7-fold increased risk of astrocytoma (95% CI = 1.6, 27.8). CONCLUSIONS: Residential proximity to cranberry bog cultivation was not associated with seven of the eight cancers investigated; however, an association was observed with brain cancer, particularly astrocytoma. Larger, more detailed studies are necessary to elucidate this relationship.

Cancer risk and tetrachloroethylene-contaminated drinking water in Massachusetts.

A population-based case-control study was used to evaluate the relationship between cases of bladder cancer (n = 61), kidney cancer (n = 35), and leukemia (n = 34) and exposure to tetrachloroethylene from public drinking water. Subjects were exposed to tetrachloroethylene when it leached from the plastic lining of drinking water distribution pipes. Relative delivered dose of tetrachloroethylene was estimated, using an algorithm that accounted for (1) residential history and duration, (2) whether lined pipe served the neighborhood, (3) distribution system flow characteristics, and (4) pipe age and dimensions. Whether or not latency was considered, an elevated relative risk of leukemia was observed among ever exposed subjects (adjusted OR = 1.96, 95% CI = 0.71-5.37, with latency; adjusted OR = 2.13, 95% CI = 0.88-5.19, without latency) that increased further among subjects whose exposure level was over the 90th percentile (adjusted OR = 5.84, 95% CI = 1.37-24.91, with latency; adjusted OR = 8.33, 95% CI = 1.53-45.29, without latency). When latency was ignored, there was also an increased relative risk of bladder cancer among subjects whose exposure level was over the 90th percentile (adjusted OR = 4.03, 95% CI = 0.65-25.10). Given that tetrachloroethylene is a common environmental and workplace contaminant in the United States, its carcinogenic potential is a matter of public health concern.

Maternal ethnicity and birthweight among blacks.

This paper examines the association of ethnicity and birthweight, adjusted for other maternal and infant characteristics, among black women who gave birth in Massachusetts from 1987 through 1989. Data are drawn from the standard certificate of live birth, which includes questions on race and ethnicity/ancestry as well as birthweight; maternal sociodemographic and biological characteristics; access to prenatal care; and infant characteristics. The study cohort consists of 18,571 black infants and a comparison group of 206,358 non-Hispanic white infants. Infants whose mothers reported their race as black were further categorized into six ethnic groups: American, Haitian, West Indian, Cape Verdean, Hispanic, and other black. In addition to descriptive analyses, we used multiple linear regression to measure the association between ethnicity, other characteristics, and birthweight; and we used multiple logistic regression to measure the odds ratio of low birthweight (ranging from 500 g to 2499 g) for the six black ethnic groups, adjusted for other characteristics. Results indicate that Americans have lower mean birthweight and generally higher levels of risk than other black ethnic groups. Compared to the reference group of non-Hispanic whites, Americans (OR = 1.49), other blacks (OR = 1.41), and West Indians (OR = 1.37) have significantly elevated relative risks of low birthweight.

The predictive value of bone marrow morphologic characteristics and immunostaining in primary (AL) amyloidosis.

The authors previously demonstrated that bone marrow plasmacytosis in primary (AL) amyloidosis may be monoclonal or polyclonal. However, the clinical implications of the degree of plasmacytosis and its clonality have not been studied. The authors evaluated 62 patients with AL amyloidosis, 40 of whom had monoclonal medullary plasma cells. There was complete concordance between the light chain class of the plasma cells in the monoclonal cases and that of the circulating paraprotein in the 22 cases associated with a paraprotein. The remaining 22 patients had polyclonal plasma cells, although a paraprotein was detected in 6. The degree of plasmacytosis was significantly higher among patients with monoclonal plasma cells and correlated inversely with length of survival. The authors' findings indicate that the quantitation of bone marrow plasma cells in AL amyloidosis by immunoperoxidase studies may predict the clinical course.

Combined ionizing radiation and thermal injury in the rat. Evaluation of early excision and closure of the burn wound.

The present study was undertaken to establish an animal model of combined whole-body irradiation and thermal injury and to determine the effectiveness of early excision and closure of the burn wound in such a model. Whole-body irradiation over a range of doses resulted in a predictable mortality rate, with an LD50/30 of 783 rad with 95% confidence limits of 737 and 823 rad. A controlled 10% body surface area full-thickness thermal injury resulted in no deaths in 30 animals. When combined with a standard nonlethal 10% thermal injury, varying doses of whole-body irradiation resulted in widely differing LD50/30 values in three separate cohorts of rats. Excision and closure of a 10% burn 24 hours after exposure to 200 rads did not improve survival. (J BURN CARE REHABIL 1990;11:42-5)

Vasoactive neurochemicals identified in omentum: a preliminary report.

There has been increasing interest in biologic, immunologic, and chemical activity originating from omental tissue. Since clinical improvement has been observed in some patients very shortly after surgically transposing their omentum to the spinal cord or brain, the question arose as to whether neurochemicals might be present in omental tissue; a possible explanation for some of these neurological changes. This paper reports the presence of vasoactive neurochemicals in canine omental tissue. It remains unclear, however, whether the omentum produces or simply concentrates these and other neurochemicals.

Endorphins in primate hemorrhagic shock: beneficial action of opiate antagonists.

The endogenous opiate beta-endorphin is released concomitantly with adrenocorticotropin from the pituitary during stress. In the present study we investigated the possible involvement of opiate receptors in the cardiovascular depression associated with hypovolemic shock in the nonhuman primate. Changes in circulating levels in beta-endorphin were monitored during hemorrhagic shock in 18 female baboons. Plasma levels of beta-endorphin increased significantly during hemorrhagic shock and were significantly correlated with a decrease in cardiac output (P less than 0.05). Single bolus administration of the opiate receptor antagonist naloxone (2 or 5 mg/kg) produced a transient but significant improvement in cardiac output (P less than 0.05) and mean arterial pressure (P less than 0.05). Hemodynamic improvement was maintained with a constant infusion of naloxone. Opiate receptor blockade with the longer acting antagonist naltrexone (2 or 5 mg/kg) significantly increased mean arterial pressure (MAP; P less than 0.05), and CO (P less than 0.05), and decreased heart rate. Our results suggest that the baboon is an excellent model for the study of hemorrhagic shock and provide further evidence for endogenous opiate involvement in the cardiovascular pathophysiology of hemorrhagic shock.

Effect of an opiate antagonist (naloxone) and an agonist/antagonist (nalbuphine) in primate hemorrhagic shock: relationship to catecholamine release.

Recent evidence has suggested a relationship between the endogenous opioid peptides and the pathophysiology of various shock states. In the present study, we investigated the relationship between the effectiveness of naloxone (an opiate antagonist) and nalbuphine (an opiate agonist/antagonist), and the changes in circulating levels of catecholamines in the nonhuman primate subjected to hemorrhagic shock. Plasma levels of catecholamines were measured using high-performance liquid chromatography (HPLC) during hemorrhagic shock in 15 female baboons. Plasma levels of both epinephrine and norepinephrine increased significantly during hemorrhagic shock (p less than 0.05), which correlated with an increase in heart rate. Bolus administration of naloxone (5 mg/kg) significantly increased both plasma epinephrine (p less than 0.01) and norepinephrine (p less than 0.05) over shock levels along with a transient but significant increase in cardiac output (p less than 0.05) and mean arterial pressure (p less than 0.05), and a significant decrease in heart rate (p less than 0.05). Improvements in hemodynamics were maintained with a constant infusion of naloxone (5 mg/kg/hr), which also caused a further significant increase in plasma epinephrine (p less than 0.01). Administration of a single bolus of the opiate agonist/antagonist nalbuphine (5 mg/kg) dramatically decreased cardiac output and mean arterial pressure and had no effect on circulating catecholamines. Our results suggest that (1) the beneficial action of high-dose naloxone in primate hemorrhagic shock may be attributable in part to a drug-induced increase in circulating endogenous catecholamines; and (2) the failure of high-dose nalbuphine to improve cardiovascular function may be related to its partial agonist (cardiodepressant) properties at higher doses.