Biomedical subjects

W D King

Publications and source records attributed to W D King.

At least 19 recordsLinked to original sources

PubMed2002

Coffee and tea consumption and cancers of the bladder, colon and rectum.

Coffee has been observed to be associated weakly or not at all with bladder cancer risk, inversely with colon cancer risk, and inconsistently with rectal cancer risk. The association between these cancers and consumption of coffee and tea was examined in a single case-control study conducted in Ontario, Canada from 1992 to 1994. A questionnaire was filled out by 927 bladder cancer cases, 991 colon cancer cases, 875 rectal cancer cases, and 2118 population controls. Although bladder cancer risk was not associated with coffee or tea, risk estimates associated with coffee among subjects who had never smoked were non-significantly increased. Colon cancer risk was inversely associated with coffee. Relative to those drinking less than 1 cup of coffee per day, the odds ratios (OR) for those drinking 1-2 cups was 0.9 (95% CI 0.8-1.1), for those drinking 3-4 cups was 0.8 (95% CI 0.7-1.0), and for those drinking 5 or more cups was 0.7 (95% CI 0.5-0.9); these ORs decreased linearly (P = 0.008). The reduced risk estimates were more pronounced with cancer of the proximal colon than the distal colon. Rectal cancer risk was not associated with either coffee or tea. Coffee consumption was observed to have a different relationship for each of the cancer sites and tea consumption was not related to any cancer site.

Case-Control Studies↗

PubMed2001

An ecologic study of childhood leukemia and population mixing in Ontario, Canada.

OBJECTIVE: To examine the association between population mixing and the incidence of childhood leukemia, specifically the acute lymphocytic leukemia (ALL) subtype among young children. METHODS: This ecologic study was based on incidence rates of leukemia in children aged 0-14 years. The Ontario Cancer Registry was used to identify the residence of 1394 leukemia cases between 1978 and 1992. Ecologic units were composed of census subdivisions in a 5-year period. Percent population change, determined from the Census of Canada, was employed as a measure of population mixing. The relationship between population mixing and childhood leukemia was examined separately after stratifying by the level of geographic isolation, defined according to urban-rural status. Analyses were also conducted separately in specific age groups and for the ALL subtype. RESULTS: Population growth in rural areas was associated with an increased incidence of leukemia, particularly for the ALL subtype in children aged 0-4 years (rate ratio = 1.8, 95% confidence interval 1.1-2.8, for a greater than 20% population change relative to no increase in population). In contrast, an elevated risk due to population mixing was not observed in urban areas. CONCLUSIONS: Results from this study are consistent with results from similar studies conducted in the United Kingdom, which are suggestive of a role for an infectious agent in the etiology of childhood leukemia, as proposed in the Kinlen hypothesis.

Adolescent↗

PubMed2001

Relation between trihalomethane compounds and birth defects.

OBJECTIVES: To evaluate the risk of birth defects relative to exposure to specific trihalomethanes in public water supplies. METHODS: A retrospective cohort study was conducted based on data from a population based perinatal database in Nova Scotia, Canada and from the results of routine water monitoring tests. The cohort consisted of women who had a singleton birth in Nova Scotia between 1988 and 1995 and who lived in an area with a municipal water supply. The birth defects analyzed included neural tube defects, cardiovascular defects, cleft defects, and chromosomal abnormalities. Two of the four trihalomethane compounds occur in large enough concentrations to be analyzed (chloroform and bromodichloromethane (BDCM)). RESULTS: Exposure to BDCM at concentrations of 20 microg/l or over was associated with an increased risk of neural tube defects (adjusted relative risk (RR) 2.5, 95% confidence interval (95% CI) 1.2 to 5.1) whereas exposure to chloroform was not. Exposure to BDCM of 20 microg/l and over was associated with decreased risks of cardiovascular anomalies (RR 0.3, 95% CI 0.2 to 0.7). There was a suggestion of an increased risk of chromosomal abnormalities associated with exposure to chloroform, and no evidence of any association between either trihalomethane compound and cleft defects. CONCLUSIONS: In this cohort, differences were found in the RR associated with exposure to chloroform and BDCM for each of the congenital anomalies under study. These findings point to the importance of examining specific byproduct compounds relative to risk for these birth outcomes and in particular implicate BDCM and other correlated disinfection byproducts in the aetiology of neural tube defects.

Abnormalities, Drug-Induced↗

PubMed2000

Relation between stillbirth and specific chlorination by-products in public water supplies.

During water treatment, chlorine reacts with naturally occurring organic matter in surface water to produce a number of by-products. Of the by-products formed, trihalomethanes (THMs) are among the highest in concentration. We conducted a retrospective cohort study to evaluate the relationship between the level of total THM and specific THMs in public water supplies and risk for stillbirth. The cohort was assembled from a population-based perinatal database in the Canadian province of Nova Scotia and consisted of almost 50,000 singleton deliveries between 1988 and 1995. Individual exposures were assigned by linking mother's residence at the time of delivery to the levels of specific THMs monitored in public water supplies. Analysis was conducted for all stillbirths and for cause-of-death categories based on the physiologic process responsible for the fetal death. Total THMs and the specific THMs were each associated with increased stillbirth risk. The strongest association was observed for bromodichloromethane exposure, where risk doubled for those exposed to a level of [greater and equal to] 20 microg/L compared to those exposed to a level < 5 microg/L (relative risk = 1. 98, 95% confidence interval, 1.23-3.49). Relative risk estimates associated with THM exposures were larger for asphyxia-related deaths than for unexplained deaths or for stillbirths overall. These findings suggest a need to consider specific chlorination by-products in relation to stillbirth risk, in particular bromodichloromethane and other by-product correlates. The finding of a stronger effect for asphyxia deaths requires confirmation and research into possible mechanisms.

Adult↗

PubMed2000

Evaluation of emergency department referrals by telephone triage.

OBJECTIVE: Telephone triage programs are becoming very common at children's hospitals across the nation. One of the proposed benefits of these programs is the more efficient use of health care resources by triaging patients to the appropriate level of health care. The purpose of this study is to examine the appropriateness of referrals to a pediatric emergency department (ED) by the Pediatric Health Information Line (PHIL), a hospital-based telephone triage program, versus all other sources of referrals. METHODS: A blinded Delphi rating system was used to review the physician's sheets of 133 consecutive ED referrals by PHIL for medical appropriateness. A total of 260 randomly selected control patients seen in the ED during the same period were similarly reviewed. If 2 of 3 pediatric emergency medicine physicians agreed that an ED visit was appropriate, then it was considered appropriate. A comparison of the 2 groups' ED appropriateness was made using a contingency table chi(2) test. An odds ratio with confidence limits was also calculated. Demographic data were collected for both groups including age, race, gender, and insurance status. RESULTS: The PHIL group had an appropriateness rate of 80.2%, compared with 60.5% for the control group (chi(2) = 14.6369; odds ratio = 2.65; 95% confidence interval [1.5759,4.5008]). CONCLUSIONS: This demonstrated that for the period studied, PHIL referrals to the ED had a 33% higher rate of appropriateness than controls. This evidence supports telephone triage as an efficient gatekeeper for health care resources.

Alabama↗

PubMed2000

Case-control study of colon and rectal cancers and chlorination by-products in treated water.

This population-based case-control study was conducted in southern Ontario, Canada from 1992 to 1994 to assess the relationship between chlorination by-products in public water supplies and cancers of the colon and rectum. Interviews providing residence and water source histories were completed by 76% of eligible cancer cases and 72% of eligible controls. Supplemental data from municipal water supplies were used to estimate individual exposure to water source, chlorination status, and by-product levels as represented by trihalomethanes (THMs) during the 40-year period before the interview. The analyses included 767 colon cases, 661 rectal cases, and 1545 controls with exposure information for at least 30 of these years (75% of subjects with completed interviews). Among males, colon cancer risk was associated with cumulative exposure to THMs, duration of exposure to chlorinated surface water, and duration of exposure to a THM level > or = 50 microg/liter and 75 microg/liter. Males exposed to chlorinated surface water for 35-40 years had an increased risk of colon cancer compared with those exposed for < 10 years (odds ratio, 1.53; 95% confidence interval, 1.13-2.09). Males exposed to an estimated THM level of 75 microg/liter for > or = 35 years had double the risk of those exposed for < 10 years (odds ratio, 2.10; 95% confidence interval, 1.21-3.66). In contrast, these relationships were not observed among females. No relationship was observed between rectal cancer risk and any of the measures of exposure to chlorination by-products. The results of this study should be interpreted with caution because they are only partially congruent with the limited amount of literature addressing this issue.

Adult↗

PubMed1999

Association of cutaneous malignant melanoma with intermittent exposure to ultraviolet radiation: results of a case-control study in Ontario, Canada.

BACKGROUND: Although solar radiation is well established as a risk factor for melanoma, it is less clear how the pattern and timing of exposure to ultraviolet (UV) radiation might be important. The particular objective of this study was to evaluate the association of melanoma risk with various measures of intermittent and chronic exposures to UV radiation, and to assess how these exposures interact with other risk factors such as skin type. METHODS: Data were analysed from a large case-control study (583 cases, 608 controls) of malignant melanoma, carried out in southern Ontario, Canada. RESULTS: Significant risk increases were identified with several measures of intermittent exposure, including beach vacations in adolescence and in the past 5 years, previous sunburn, and use of sunbeds and sunlamps. Chronic exposure, indicated by days of outdoor activity during adolescence and by occupation in recent adult life, was associated with significantly reduced risk. Subgroup analyses showed: no major risk differences by body site of melanoma; stronger association of lentigo maligna melanoma with intermittent exposure; more pronounced effects of beach vacations and sunburn in younger subjects; and consistently higher risks for intermittent exposures among subjects with skin more susceptible to burning. CONCLUSIONS: The data lend limited support to the hypothesis of increased risk associated with intermittent UV exposure. The findings suggest that future studies should take age at diagnosis, host susceptibility and histological subtype into account.

Adult↗

PubMed1999

Effect of ketorolac in pediatric sickle cell vaso-occlusive pain crisis.

BACKGROUND: Ketorolac is a parenteral, nonsteroidal analgesic that does not have a narcotic's risks of respiratory depression, hypotension, or dependence. Its usefulness in providing pain relief in pediatric patients with acute vaso-occlusive crisis of sickle cell disease has not been studied to date. METHODS: Twenty-nine patients with sickle cell disease between the ages of 5 and 18 years who presented to The Children's Hospital of Alabama emergency department (ED) with 41 distinct episodes of acute vaso-occlusive pain crisis were enrolled prospectively and randomized to receive either 0.9 mg/kg intravenous (IV) ketorolac or placebo in a double-blind fashion. All patients also received IV fluids and an initial 0.1 mg/kg of IV morphine. Subsequent standardized doses of morphine were given every 2 hours over a 6-hour observation period based upon severity of pain as scored by a 10-cm linear visual analog scale (VAS). Vital signs and pain severity were recorded initially and assessed hourly. Disposition was made at the end of the observation period. RESULTS: Patients receiving ketorolac and those receiving placebo were of similar age, weight, gender, number of prior ED visits, number of prior hospital admissions, duration of pain prior to presentation, and initial pain score. The total dose of morphine received, reduction in severity of pain as measured by VAS, rate of hospital admission, and rate of return to the ED for discharged patients did not differ significantly between the two groups. CONCLUSION: We were unable to demonstrate a synergistic analgesic effect for ketorolac in the treatment of pain from acute vaso-occlusive crisis in pediatric sickle cell disease. Further investigations involving larger samples of sickle cell patients may be needed to further define a role for ketorolac in the acute management of sickle cell vaso-occlusive pain.

Adolescent↗

PubMed1999

Survey of the stocking of poison antidotes in Alabama hospitals.

BACKGROUND: We wanted to estimate the current antidote supply in Alabama hospitals, establish if certain antidotes were stocked more than others, and identify certain parameters (eg, treatment level of care, licensed bed size, or county population) as predictors for the current antidote supply. METHODS: We faxed surveys to treatment level I/II hospitals and a random sample of treatment level III hospitals. Antidote supply was reported for digoxin immune Fab, pyridoxine, ethanol, pralidoxime, antivenin (Crotalidae), deferoxamine, cyanide, naloxone, and fomepizole. RESULTS: Of treatment level I/II and level III hospitals surveyed, 28 (100%) and 20 (71.4%) responded, respectively. None (0%) of the hospitals surveyed had adequate stocking for all nine antidotes. The results illustrate the common practice of understocking poison antidotes. CONCLUSIONS: Hospitals must reevaluate their current antidote inventories for meeting the needs of acutely poisoned patients. Policy containing specific guidelines must be developed and uniformly adopted as standard of practice.

Alabama↗

PubMed1999

Suicides among Canadian farm operators.

The objective of this epidemiologic study was to describe rates of suicide among male farm operators in Canada and to compare rates with those in the general male population. The data were obtained from the Canadian Farm Operator Cohort (CFOC) database. Outcome measures were age-specific and age-standardized rates of completed suicide (ICD-9-CM E-codes 950-959). A total of 1,457 cases of suicide were identified from the CFOC for the years 1971- 1987. Age-standardized rates of suicide for those aged 30-69 were 29.2 (95% CI = 27.3-31.1) per 100,000 person-years (PYs) in the CFOC, 24. 0 (95% CI = 22.1-25.8) per 100,000 PYs in the CFOC excluding Quebec (which had data linkage concerns) and 27.0 (95% CI = 26.6-27.3) per 100,000 PYs among Canadian males in general. Age-specific rates of suicide in the CFOC increased over time. After adjustment for age differences, provincial suicide rates among farm operators were generally lower than or equivalent to those observed in the comparison populations of Canadian males. The implications of these results are discussed. We speculate that high levels of social support traditionally available in Canadian farm communities may protect farm operators from abnormally high rates of suicide.

Adult↗

PubMed1998

Suicide mortality and pesticide use among Canadian farmers.

BACKGROUND: An exploratory, case-control study was used to investigate a new hypothesis about suicide among farm operators. This hypothesis suggested a biologically plausible link between exposures to certain pesticides and the occurrence of suicide among farm operators. These analyses were based on data from the Canadian Farm Operator Cohort. METHODS: Canadian male farm operators who committed suicide between 1971-1987 (n = 1,457) were compared with a frequency matched (by age and province) sample of control farm operators (n = 11,656) who were alive at the time of death of individual cases. Comparisons focused on past exposures to pesticides reported to the 1971 Canada Census of Agriculture. RESULTS: Multivariate logistic regression analyses indicated no associations between suicide and (1) acres sprayed with herbicides, (2) acres sprayed with insecticides, and (3) the costs of agricultural chemicals purchased; after controlling for important covariates. There was, however, a suggestive increase in risk for suicide associated with herbicide and insecticide spraying among a subgroup of farm operators who were most likely to be directly exposed to pesticides: OR = 1.71 (95% CI = 1.08-2.71) for 1-48 vs. 0 acres sprayed. Additional risk factors that were identified included seasonal vs. year-round farm work (OR = 1.68; 95% CI = 1.15-2.46); and high levels of paid labor on the farm (e.g., OR = 1.61; 95% CI = 1.24-2.10, for > 13 vs. 0 weeks per year). Factors that were protective included marriage (odds ratio (OR) = 0.69; 95% confidence interval (CI) = 0.58-0.81), having more than one person resident in the farm house (e.g., two vs. one person; OR = 0.62; 95% CI = 0.42-0.92); and higher levels of education (e.g., postsecondary vs. primary; OR = 0.40; 95% CI = 0.17-0.96). CONCLUSIONS: This study does not provide strong support for the main hypothesis under study, that exposure to pesticides is an important risk factor for suicide among farmers. Although secondary to the main hypothesis, a number of other risk factors for suicide were suggested. These have implications for the future study and targeting of suicide prevention programs in rural Canada.

Adult↗

PubMed1998

Epidemiology of hospitalization for near-drowning.

BACKGROUND: Although drowning is the third leading cause of accidental death among children less than 4 years of age, few studies have described the hospitalization of near-drowning victims. Our study emphasizes the local epidemiology and charges associated with pediatric hospitalization in cases of near-drowning. METHODS: Data regarding time, place, injury severity, circumstances, outcome, and hospital charges were collected by retrospective medical record review. Cross tabulation of datasets with descriptive statistical analysis was done using R:Base System V. RESULTS: Between 1987 and 1991, 53 victims of near-drowning were admitted or transferred to Children's Hospital of Alabama in Birmingham. Thirty-three of the incidents occurred during the months of June, July, and August; 32 occurred in pools, 11 in lakes and rivers, 6 in bathtubs, 3 in mop buckets, and 1 in a cesspool. The mean hospital stay was 8 days (combined total, 439 days), accounting for total charges of $749,507 (mean $14,141). Outcomes included 15 deaths, 5 discharges with neurologic sequelae, and 33 discharges without sequelae. Private insurance covered 31 patients, 7 were Medicaid patients, and 15 had no coverage. CONCLUSION: Near-drowning injuries have high case fatality rates, a high case sequelae rate, and high hospitalization charges.

Alabama↗

PubMed1998

Pediatric pedestrian injuries: a community assessment using a hospital surveillance system.

OBJECTIVE: To provide a descriptive demographic and environmental account of pedestrian injuries among children aged < or =15 years in Jefferson County, Alabama. METHODS: This was a retrospective study with a case definition for inclusion of individuals, aged < or =15 years, who suffered a pedestrian injury and sought care at The Children's Hospital of Alabama between 1989 and 1991. Demographic and injury-related information was obtained from the medical record and analyses were performed using t-test and a simple correlation. RESULTS: The majority of the cases were nonwhite, and nearly half had Medicaid or were uninsured. The most common injuries were fractures and closed head trauma. The geographic locations of injury events were not uniformly distributed: a comparison of areas wherein an injury occurred with those that were injury-free revealed a number of significant differences with regard to specific demographic, socioeconomic, and ecological factors. CONCLUSIONS: Some of the possible manageable environmental risk factors identified in this study were relatively high posted speed limits; sidewalks that were narrow, absent, or in a state of disrepair; vehicular parking on both sides of the street; and the absence of a divided highway. In this community, the most cost-effective educational intervention may best be targeted to elementary-aged schoolchildren living in areas with low-income families and that have a high density of children.

Accidents, Traffic↗

PubMed1998

Toppled television sets cause significant pediatric morbidity and mortality.

OBJECTIVE: To quantify pediatric injuries and deaths that result from toppled television sets. DESIGN: Retrospective analysis of incident files compiled by the US Consumer Product Safety Commission (CPSC) data systems and The Children's Hospital of Alabama (TCHA) inpatient medical records. SETTING: United States, January 1990-June 1997. TCHA, May 1995-October 1997. MAIN OUTCOME MEASURES: Morbidity or mortality as a result of a television set falling onto a child. RESULTS: Over the 7-year period from January 1990 to June 1997, 73 cases that involved falling television sets were reported to the CPSC, including 28 deaths. The mean age of all victims was 36 months (SD +/- 25.4 months). The mean age of those who died was 31 months (SD +/- 22 months). Females accounted for 42 incidents (58%) and 19 deaths (68%). The most common anatomic site of injury was the head, which accounted for 72% of cases investigated by CPSC personnel. Of the 14 deaths further investigated by the CPSC, head injury was responsible for 13, with a generalized crushing injury accounting for the other. Of the 45 cases in which data were available, dressers or stands were identified as the television support 76% of the time. The TCHA database yielded five additional cases, including one death, with demographics similar to the CPSC data. CONCLUSION: Serious injury and death can occur as a result of children toppling television sets from elevated locations in the home. The furniture on which a television set is situated is of fundamental importance. An estimate of overall risk to the population is impossible to determine from these data. In light of 73 reported cases with 28 deaths; however, injury prevention counseling and other strategies supporting in-home safety should include a secure and child-safe location for television sets. Attention should be paid to safer design and placement of this ubiquitous product. television, wounds and injuries, accidents, human, infants, children.

Accidental Falls↗

PubMed1997

Clonidine poisoning in Jefferson County, Alabama.

STUDY OBJECTIVE: To describe the epidemiology of clonidine-related hospitalization in children, to evaluate the efficacy of naloxone, and to review the clinical effects of clonidine toxicity. METHODS: This was a retrospective analysis in an urban teaching pediatric emergency department with an annual census of 55,000 involving 80 children younger than 6 years who were admitted for clonidine ingestion during a 6-year period. RESULTS: Clonidine commonly belonged to the patient's grand-mother (54%). Black children were twice as likely to be hospitalized for clonidine ingestion than white children compared with children hospitalized for any injury. Average time to onset of symptoms was 35 minutes. Decreased level of consciousness was the most common presenting symptom (96%). Mean ED vital signs were systolic blood pressure, 102 mm Hg; pulse, 98; respirations, 25 (six patients intubated); and temperature, 36.6 degrees C, Naloxone was administered to 49% of patients, 84% of whom demonstrated no response. CONCLUSION: Clonidine ingestion is endemic in our area. Serious clinical effects mandate that all children with clonidine ingestion be triaged to a health care facility. Naloxone as an antidote for clonidine remains controversial.

Black or African American↗

PubMed1997

Respiratory depression in a child unintentionally exposed to transdermal fentanyl patch.

A 2-year-old boy was found unresponsive after sleeping in bed with his grandmother. After the patient was intubated and ventilated, paramedics discovered a transdermal fentanyl patch on the victim's back. Removal of the patch and treatment with naloxone resolved symptoms. This is the first reported case of secondary exposure to a fentanyl patch causing clinically significant respiratory depression in the pediatric population, and it emphasizes a new hazard of such drug use.

Administration, Cutaneous↗

PubMed1997

Fatal iron intoxication in an infant.

Iron ingestion continues to be one of the major contributors to pediatric poisoning deaths. In 1995, more than 22,000 children unintentionally received preparations containing iron. Despite child-resistant packaging and education of both the public and medical personnel, the number of deaths has not significantly declined. Our patient, a 13-month-old child, ingested prenatal vitamins and despite aggressive efforts died 13 hours after his initial presentation. The patient's 3-year-old sibling had been evaluated at a local hospital 12 hours earlier for iron ingestion. Although there have been previous reports of death from iron ingestion, this case report is important because of the sibling's presentation and medical evaluation 12 hours before our patient's presentation. This case illustrates the need for physicians to inquire about other children in the home, possibly preventing further tragic outcomes.

Fatal Outcome↗

PubMed1996

Case-control study of bladder cancer and chlorination by-products in treated water (Ontario, Canada).

Chlorine is by far the most commonly used chemical for the disinfection of water supplies in North America. However, chlorine reacts with organic material in the raw water producing a number of halogenated hydrocarbon by-products. This population-based case-control study in Ontario, Canada examined the relationship between bladder cancer and exposure to chlorination by-products in public water supplies. Residence and water source histories and data from municipal water supplies were used to estimate individual exposure according to water source, chlorination status, and by-product levels (represented by trihalomethane [THM] concentration). Exposures were estimated for the 40-year period prior to the interview, using 696 cases diagnosed with bladder cancer between 1 September 1992 and 1 May 1994 and 1,545 controls with at least 30 years of exposure information. Odds ratios (OR) adjusted for potential confounders were used to estimate relative risk. Those exposed to chlorinated surface water for 35 or more years had an increased risk of bladder cancer compared with those exposed for less than 10 years (OR = 1.41, 95 percent confidence interval [CI] = 1.10-1.81). Those exposed to an estimated THM level > or = 50 micrograms/liter for 35 or more years had 1.63 times the risk of those exposed for less than 10 years (CI = 1.08-2.46). These results indicate that the risk of bladder cancer increases with both duration and concentration of exposure to chlorination by-products, with population attributable risks of about 14 to 16 percent. Chlorination by-products represent a potentially important risk factor for bladder cancer.

Case-Control Studies↗