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Biomedical subjects

T Heeren

Publications and source records attributed to T Heeren.

71 records · Page 4Linked to original sources
PubMed1984

Adenocarcinoma and Barrett's esophagus. An overrated risk?

The risk of developing esophageal cancer in Barrett's esophagus has been estimated at about 10%. This estimate is based primarily on data concerning the prevalence of that association in series of hospitalized patients and autopsies--a practice that tends to exaggerate the risk. We have reviewed retrospectively our experience with 115 patients whom we treated for Barrett's esophagus between September 1962 and March 1983, and have distinguished our data on the prevalence of esophageal cancer from that on incidence. For 8 patients, we found both Barrett's esophagus and esophageal adenocarcinoma during the initial evaluations for a prevalence ratio of 7%. We followed 105 patients not found to have esophageal cancer initially for a total of 350 person-years. Only 2 patients developed adenocarcinoma during that follow-up period for an incidence of 1 case per 175 person-years. This incidence, although some 40-fold greater than that of the general population, is substantially lower than previously estimated. Routine endoscopic and histologic surveillance has been recommended for patients with Barrett's esophagus because of the alleged high incidence of esophageal cancer. Inasmuch as that incidence now appears to be low, we question the value of such surveillance for these patients.

Adenocarcinoma↗
PubMed1983

Impact of legislation raising the legal drinking age in Massachusetts from 18 to 20.

On April 16, 1979, Massachusetts raised its legal drinking age from 18 to 20 years. Massachusetts was compared with New York State, exclusive of New York City and Nassau County. New York State retained an 18-year-old drinking age. Random telephone surveys with approximately 1,000 16-19 year olds in each state were undertaken prior to the law's enactment and twice at yearly intervals after the law to assess the law's impact on teenage drinking, driving after drinking, and non-fatal accident involvement. Fatal crash data reported to the US Department of Transportation by each state from April 16, 1976-April 15, 1981 were also analyzed. After the law, although the modes of procuring alcohol changed. No significant changes were observed in Massachusetts relative to New York in the proportion of surveyed teenagers who reported that they drank or in the volume of their consumption. The proportion of teenagers who drove after drinking heavily (six or more drinks at one time) did not decline in Massachusetts relative to New York. However, the frequency that teenagers reported driving after any drinking declined significantly in Massachusetts. Frequency of teenage driving after marijuana use and non-fatal teenage accidents declined at comparable rates in both states. The numbers of teenage nighttime single vehicle fatal accidents declined more in Massachusetts than New York, in the 18-19 year age group. Overall fatal accident trends among 16-19 year olds in the two states were similar.

Accidents, Traffic↗
PubMed1982

Maternal cigarette smoking, psychoactive substance use, and infant Apgar scores.

A study of 1,709 mother/child pairs at Boston City Hospital examined whether maternal cigarette smoking, drinking, or the use of other psychoactive substances was associated with low infant Apgar scores. The potential confounding effects of other labor and delivery risks were controlled in the analysis. In contrast to previous reports, univariate and stepwise multiple regression analyses did not identify a significant negative association between cigarette smoking and 1- or 5-minute Apgar scores. None of the substance use variables was significantly associated with low infant Apgar scores at 1 and 5 minutes. Other labor and delivery risks, such as short length of gestation, abnormal delivery presentation, placental abnormalities, nuchal cord, and exposure to general anesthesia during delivery, were associated with low Apgar scores.

Adult↗
PubMedDate not supplied

Comorbidities, complications, and coding bias. Does the number of diagnosis codes matter in predicting in-hospital mortality?

OBJECTIVE: Incomplete coding of secondary diagnoses may bias assessments of patient risks of poor outcomes using administrative health care databases, most of which allow only five diagnoses. The Medicare program is expanding the number of possible diagnoses from five to nine, aiming to improve coding completeness. We examined the impact of having more diagnosis codes available on assessments of risk of death. DESIGN: We used 1988 computerized hospital discharge abstract data from California, which allow up to 25 diagnoses per discharge, to select a sample of hospitalized patients and assessed the relationship between the presence of 29 specific secondary diagnoses and the risk of in-hospital death. SETTING: Nonfederal acute-care hospitals in California. STUDY POPULATION: All patients at least 65 years of age who were hospitalized for stroke, pneumonia, acute myocardial infarction, or congestive heart failure in California in 1988 (N = 162,790). MAIN OUTCOME MEASURES: Relative risk of death for each specific secondary diagnosis. RESULTS: Many conditions that on a clinical basis would be expected to increase the risk of death, such as adult-onset diabetes mellitus, previous myocardial infarction, angina, and ventricular premature beats, were associated with a lower risk of in-hospital death. CONCLUSIONS: Bias against coding of chronic or comorbid conditions on the computerized discharge abstracts of patients who die best explains these results. Efforts to improve diagnosis coding completeness solely by increasing the number of available coding spaces may not succeed.

Aged↗
PubMedDate not supplied

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.

Adult↗
PubMedDate not supplied

Robustness of the two independent samples t-test when applied to ordinal scaled data.

One may encounter the application of the two independent samples t-test to ordinal scaled data (for example, data that assume only the values 0, 1, 2, 3) from small samples. This situation clearly violates the underlying normality assumption for the t-test and one cannot appeal to large sample theory for validity. In this paper we report the results of an investigation of the t-test's robustness when applied to data of this form for samples of sizes 5 to 20. Our approach consists of complete enumeration of the sampling distributions and comparison of actual levels of significance with the significance level expected if the data followed a normal distribution. We demonstrate under general conditions the robustness of the t-test in that the maximum actual level of significance is close to the declared level.

Biometry↗
PubMedDate not supplied

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.

Adolescent↗
PubMedDate not supplied

Relationship of psychiatric status to Gulf War veterans' health problems.

OBJECTIVE: A growing body of research has shown that there are important links between certain psychiatric disorders and health symptom reporting. Two disorders in particular (posttraumatic stress disorder (PTSD) and major depression) have been the most widely implicated to date, and this association has sometimes been used to explain the occurrence of ill-defined medical problems and increased somatic symptoms in certain groups, most recently Gulf War veterans. METHODS: Structured psychiatric diagnostic interviews were used to examine the presence of major psychiatric (axis I) disorders and their relation to health symptom reporting in a well-characterized, stratified subset of Gulf War veterans and a non-Gulf-deployed veteran comparison group. RESULTS: Rates of most psychiatric disorders were substantially lower than national comorbidity estimates, consistent with prior studies showing heightened physical and emotional well-being among active-duty military personnel. Rates of PTSD and major depression, however, were significantly elevated relative to the veteran comparison group. The diagnosis of PTSD showed a small but significant association with increased health symptom reports. However, nearly two-thirds of Gulf participants reporting moderate to high health symptoms had no axis I psychiatric diagnosis. CONCLUSIONS: Results suggest that rates of psychiatric illness were generally low with the exception of PTSD and major depression. Although PTSD was associated with higher rates of reported health problems, this disorder did not entirely account for symptoms reported by participants. Factors other than psychiatric status may play a role in Gulf War health problems.

Cohort Studies↗
PubMedDate not supplied

A mediational model for the impact of exposure to community violence on early child behavior problems.

This study examined how maternal distress mediates the link between exposure to community violence (CV) and the development of early child behavior problems. Research was conducted among 160 children, 3,0 to 5,11 in age, who resided in high-crime neighborhoods. Using structural equation modeling, latent variables were constructed to identify model components: maternal socioeconomic status (SES) and public assistance status, exposure to CV (maternal perceptions of local violence, social disorder, and fear of crime; and frequency of child cowitnessing violent events), family aggression (partner aggression toward mother and partner aggression toward child), maternal distress (global distress and posttraumatic stress disorder symptoms), and early child behavior problems (internalizing and externalizing). Bivariate correlations indicated that CV, maternal distress, and early child behavior problems were significantly intercorrelated. A series of structural equation models was specified to estimate the direct and indirect effect of CV on early child behavior problems. A direct model indicated a significant path from CV to early child behavior problems, after controlling for maternal SES and family aggression. The direct CV-early child behavior problems path diminished, however, when maternal distress was included in the model, after controlling for maternal SES and family aggression. Results are consistent with a mediation model of the impact of maternal distress symptoms on the link between CV and early child behavior problems.

Black or African American↗
PubMedDate not supplied

Treatment of malignant pleural mesothelioma with cisplatin, mitomycin C and alpha interferon.

From October 1990 to September 1991, 20 consecutive patients with histologically proven malignant pleural mesothelioma (MPM), secondary to environmental exposure to asbestos or erionite, were treated with cisplatin, mitomycin C and alpha interferon (cisplatin 50 mg/m2 i.v. on day 1 of a 21-day cycle; mitomycin C 10 mg/m2 i.v. day 1 of cycles 1,3 and 5; alpha-2b-interferon 10 x 10(6) units i.m., 4 h prior to cisplatin and 10 x 10(6) units i.v. immediately prior to cisplatin day 1 of each cycle). Eighty-two treatment cycles were administered to 19 evaluable patients. Two patients attained a partial response. Eleven patients had stable disease and 6 had disease progression. Toxicities included interferon-related fever and flu-like symptoms, and vomiting. Actuarial median survival was 15 months. Three patients are alive at 20+, 21+ and 27+ months. We conclude that while the addition of alpha interferon to cisplatin and mitomycin C did not result in an objective response higher than previously reported with the cytotoxic agents alone, the trend towards an improvement in median survival as compared to a well-matched historical group suggests some benefit from the inclusion of interferon.

Adult↗
PubMedDate not supplied

The social epidemiology of alcohol use by urban older adults.

A sample survey of 928 Bostonians, aged sixty years or older, indicates that there are low levels of alcohol consumption: more than half report that they are abstainers; 6 percent indicate that they have two or more drinks daily. Levels of abstinence are particularly high among women, blacks, Jews, widows and widowers, the foreign-born, those with low levels of formal education, and those aged seventy-five years or older. Among social psychological variables, locus of control is most consistently associated with drinking: those who report little influence upon their futures--in terms of work, marriage, income, and leisure activities--are more likely to abstain. There is also an association with optimisim; those who are least optimistic about their prospects for work and leisure activities are most likely to abstain. Analysis of variance shows that gender, education, ethnicity, religion, age, and locus of control regarding work are independent correlates of alcohol use. The data suggest that older people drink mainly in social contexts and to facilitate social interaction.

Age Factors↗
PubMedDate not supplied

A cross-national study of acute otitis media: risk factors, severity, and treatment at initial visit. Report from the International Primary Care Network (IPCN) and the Ambulatory Sentinel Practice Network (ASPN).

BACKGROUND: Treatment of acute otitis media (AOM) differs worldwide. The Dutch avoid antimicrobials unless fever and pain persist; the British use them for 5 to 7 days, and Americans use them for 10 days. If effects of therapies are to be compared, it is necessary to evaluate rates of risk factors, severity of attacks, and their influence on treatment decisions. We wanted to compare the prevalence of risk factors for AOM and evaluate their association with severity of attacks and of severity with antimicrobial treatment. METHODS: We undertook a prospective cohort study of 2,165 patients with AOM enrolled by primary care physicians; 895 were enrolled from North America, 571 were enrolled from the United Kingdom, and 699 were enrolled from The Netherlands. The literature was searched using the key words "acute otitis media," "severity," and "international comparisons." RESULTS: The prevalence of several AOM risk factors differs significantly among patients from the three country networks; these factors include race, parent smoking habits, previous episodes, previous episodes without a physician visit, tonsillectomy or adenoidectomy, frequency of upper respiratory tract infections, day care, and recumbent bottle-feeding. Dutch children have the most severe attacks as defined by fever, ear discharge, decreased hearing during the previous week, and moderate or severe ear pain. In country-adjusted univariate analyses, increasing age, exposure to tobacco smoke, day care, previous attacks of AOM, previous attacks without physician care, past prophylactic antimicrobials, ear tubes, adenoidectomy, and tonsillectomy all contribute to severity. Only country network, age, history of AOM, previous episode without physician care, and history of adenoidectomy and tympanostomy tubes are independently related to increased severity, while current breast-feeding is protective. Severity of attacks influences treatment decisions. Dutch children are least likely to receive antimicrobials, and even for severe attacks the British and Dutch physicians usually use amoxicillin or trimethoprim-sulfa; North American children with severe attacks are more likely to receive a broad-spectrum second-line antimicrobial. CONCLUSION: Dutch children have the highest ratings in all severity measures, possibly reflecting parental decisions about care seeking for earaches. When comparing groups of patients with AOM, it is necessary to adjust for baseline characteristics. Severity of episode affects physician treatment decisions. Adoption of Dutch guidelines restricting use of antimicrobials for AOM in the United States could result in annual savings of about $185 million.

Acute Disease↗
PubMedDate not supplied

Lower legal blood alcohol limits for young drivers.

To reduce the involvement of young drivers in alcohol-related crashes, 29 States and the District of Columbia have established lower legal blood alcohol limits for drivers younger than age 21 than for adult drivers. Of these, 12 lowered the legal limit for young people prior to 1991. To assess the impact, these 12 States were paired for comparison with 12 nearby States matched for legal drinking age and timing of changes in that law. Among drivers ages 15-20, fatal crashes involving a single vehicle at night are three times more likely than other fatal crashes to be alcohol-related. Whether the proportion of fatal crashes that involved single vehicles at night declined more among young drivers targeted by lower blood alcohol limits than among young drivers of the same age in comparison States was examined. The maximum available equal number of pre- and post-law years were compared in each pair of States. During the post-law period, the proportion of fatal crashes that involved single vehicles at night declined 16 percent among young drivers targeted by lower blood alcohol laws, whereas it rose 1 percent among drivers of the same age in comparison States where blood alcohol limits were not changed (P < .001). Among adults, the proportion of fatal nocturnal crashes that involved single vehicles declined 5 percent in the group of States with the lowered levels for young people during the period after the law was enacted and 6 percent in the group of neighboring comparison States. The proportion of fatal crashes that involved single vehicles at night declined 22 percent among drivers in States with .00 percent limits, whereas it declined only 2 percent among drivers of the same age in comparison States (P <.003). Among those targeted by .02 percent BAL limits, the proportion of fatal crashes that involved single vehicles at night declined 17 percent. It rose 4 percent in comparison States(P = .005). No significant difference appeared between States that lowered blood alcohol levels to the range of .04-.06 percent relative to comparison States.If all States adopted .00 or .02 percent limits for drivers ages 15-20, at least 375 fatal single vehicle crashes at night would be prevented each year.

Accidents, Traffic↗
PubMedDate not supplied

HIV and hepatitis B infection and risk behavior in young gay and bisexual men.

OBJECTIVES: To estimate the prevalence of and identify risk factors for human immunodeficiency virus type 1 (HIV-1) and hepatitis B virus (HBV) infections and unprotected anal intercourse among young homosexual and bisexual men. METHODS: The authors performed a cross-sectional analysis of data from a prospective cohort of 508 young gay and bisexual men ages 18-29. RESULTS: HIV-1 seroprevalence was 2.4%, with five (1.3%) of 390 college students and seven (6.0%) of 117 non-students infected. After adjusting for confounders, HIV-1 infection was associated with having a history of a sexually transmitted disease other than HIV-1 or hepatitis B. The prevalence of hepatitis B markers in unvaccinated men was 12.9%. The presence of hepatitis B markers in unvaccinated men was significantly associated with Asian ethnicity, off-campus residence, and history of a sexually transmitted disease other than HIV-1 or hepatitis B and inversely associated with recent non-intravenous drug use. Eighteen percent of the participants reported having had sex with women during the previous 12 months, and 26.4% reported a history of unprotected anal intercourse during the previous six months. Men who reported unprotected anal intercourse were more likely to have at least one steady partner, to have met their partners in anonymous settings, and to be identified as probably alcohol dependent. CONCLUSIONS: Although the prevalence of HIV-1 infection among young homosexual and bisexual men in Boston was relatively low, the high rates of unprotected anal intercourse suggest a potential for future HIV-1 and hepatitis B transmission. Interventions should focus on young men with histories of sexually transmitted diseases, alcohol abuse, and depression.

Adolescent↗
PubMedDate not supplied

Effects of Maine's 0.05% legal blood alcohol level for drivers with DWI convictions.

OBJECTIVE: To determine whether a Maine law lowering the legal blood alcohol limit (BAL) from 0.10% to 0.05% for people convicted of driving while intoxicated (DWI) reduced the involvement of this group in fatal crashes. METHODS: The authors calculated changes in the proportions of fatal crashes involving drivers with prior DWI convictions from the six-year period before enactment of the law to the six-year period following enactment of the law, comparing Maine with the other New England states. RESULTS: In Maine, the proportion of fetal crashes involving drivers with recorded prior DWI convictions declined 25% following passage of the 0.05% DWI law, while the proportion rose in the rest of New England during the same years. The proportion of fatal crashes involving drivers with recorded prior DWI convictions and illegal alcohol levels also declined significantly in Maine, as did the proportion of fatal crashes involving fatally injured drivers with recorded prior DWI convictions and illegal alcohol levels. Most of the latter decline was due to a decline in alcohol-related fatalities of previously convicted drivers with very high BALs, of 0.15% or higher, at the time of the fatal crash. Each of these declines in Maine was significant relative to the rest of New England. CONCLUSION: Other states should consider instituting 0.05% BAL limits for convicted DWI offenders.

Accidents, Traffic↗