Declining incidence of invasive Streptococcus pneumoniae infections among persons with AIDS in an era of highly active antiretroviral therapy, 1995-2000

BACKGROUND

Our goal was to describe trends in invasive pneumococcal disease incidence among persons with acquired immunodeficiency syndrome (AIDS) since the introduction of highly active antiretroviral therapy (HAART).

METHODS

We used time-trend analysis of annual invasive pneumococcal disease incidence rates from a population-based, active surveillance system. Annual incidence rates were calculated for 5 July-June periods by use of data from San Francisco county, the 6-county Baltimore metropolitan area, and Connecticut. The numerators were the numbers of invasive Streptococcus pneumoniae infections among persons 18-64 years of age with AIDS; the denominators were the numbers of persons living with AIDS, estimated on the basis of AIDS surveillance data.

RESULTS

The annual incidence of invasive pneumococcal disease declined from 1094 cases/100,000 persons with AIDS (July 1995-June 1996) to 467 cases/100,000 persons living with AIDS (July 1999-June 2000). The annual percentage changes in incidence were -34%, -29%, -8%, and -1%. Declines were similar by surveillance area, sex, and race/ethnicity. During the final year of the study, the invasive pneumococcal disease incidence in persons with AIDS was half that of the pre-HAART era but was still 35 times higher than that in similarly aged non-HIV-infected adults.

CONCLUSIONS

In the United States, invasive pneumococcal disease incidence declined sharply across a range of subgroups living with AIDS during the period after widespread introduction of HAART. Despite these gains, persons with AIDS remain at high risk for invasive pneumococcal disease.

Indoor Heating Sources and Respiratory Symptoms in Nonsmoking Women

BACKGROUND

Secondary heating appliances are important indoor sources of air pollution, including particulate matter, nitrogen dioxide (NO2), and sulfur dioxide (SO2). We hypothesized that the use of secondary heating sources increases respiratory symptoms in women living in nonsmoking households and specifically that concentrations of SO2 and NO2 emitted from heating sources are associated with respiratory symptoms.

METHODS

Mothers who delivered babies at 12 hospitals in Connecticut and Virginia (1993-1996) were enrolled. There were 888 women who contributed symptom and exposure information during the winter heating season (15 October to 15 April), for a total of 9783 reporting periods (median = 12 reporting periods per woman, interquartile range 11-12). Adjusted rate ratios (RRs) of effects of source use and measured concentrations on rate of days with symptoms were obtained using generalized estimating equations for a log-linear Poisson model, controlling age, education, race, history of allergies, number of children, dwelling type, and residence state.

RESULTS

In adjusted models, each hour-per-day increase in kerosene heater use is associated with an increase in wheezing (RR = 1.06; 95% confidence interval (CI) = 1.01-1.11). Each hour of fireplace use is associated with increased cough (1.05; 1.01-1.09), sore throat (1.04; 1.00-1.08), and marginally with chest tightness (1.05; 0.99-1.12). Each 10 ppb increase in SO2 (a proxy for sulfate aerosol) is associated with increased wheezing (1.57; 1.10-2.26) and chest tightness (1.32; 1.01-1.71).

CONCLUSIONS

Emissions from fireplaces, gas space heaters, and kerosene heaters may contribute to respiratory symptoms in a population of nonsmoking women.

Consequences of preventing delirium in hospitalized older adults on nursing home costs

OBJECTIVES

To determine whether costs of long-term nursing home (NH) care for patients who received a multicomponent targeted intervention (MTI) to prevent delirium while hospitalized were less than for those who did not receive the intervention.

DESIGN

Longitudinal follow-up from a randomized trial.

SETTING

Posthospital discharge settings: community-based care and NHs.

PARTICIPANTS

Eight hundred one hospitalized patients aged 70 and older.

MEASUREMENTS

Patients were followed for 1 year after discharge, and measures of NH service use and costs were constructed. Total long-term NH costs were estimated using a two-part regression model and compared across intervention and control groups.

RESULTS

Of the 400 patients in the intervention group and 401 patients in the matched control group, 153 (38%) and 148 (37%), respectively, were admitted to a NH during the year, and 54 (13%) and 51 (13%), respectively, were long-term NH patients. The MTI had no effect on the likelihood of receiving long-term NH care, but of patients receiving long-term NH care, those in the MTI group had significantly lower total costs, shorter length of stay and lower cost per survival day. Adjusted total costs were $50,881 per long-term NH patient in the MTI group and $60,327 in the control group, a savings of 15.7% (P=.01).

CONCLUSION

Active methods to prevent delirium are associated with a 15.7% decrease in long-term NH costs. Shorter length of stay of patients receiving long-term NH services was the primary source of these savings.

Cigarette Smoking and Risk of Non-Hodgkin Lymphoma: A Pooled Analysis from the International Lymphoma Epidemiology Consortium (InterLymph)

BACKGROUND

The International Lymphoma Epidemiology Consortium (InterLymph) provides an opportunity to analyze the relationship between cigarette smoking and non-Hodgkin lymphoma with sufficient statistical power to consider non-Hodgkin lymphoma subtype. The results from previous studies of this relationship have been inconsistent, likely due to the small sample sizes that arose from stratification by disease subtype. To clarify the role of cigarette smoking in the etiology of non-Hodgkin lymphoma, we conducted a pooled analysis of original patient data from nine case-control studies of non-Hodgkin lymphoma conducted in the United States, Europe, and Australia.

METHODS

Original data were obtained from each study and uniformly coded. Risk estimates from fixed-effects and two-stage random-effects models were compared to determine the impact of interstudy heterogeneity. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived from unconditional logistic regression models, controlling for study center, age, sex, and race.

RESULTS

In our pooled study population of 6,594 cases and 8,892 controls, smoking was associated with slightly increased risk estimates (OR, 1.07; 95% CI, 1.00-1.15). Stratification by non-Hodgkin lymphoma subtype revealed that the most consistent association between cigarette smoking and non-Hodgkin lymphoma was observed among follicular lymphomas (n = 1452). Compared with nonsmokers, current smokers had a higher OR for follicular lymphoma (1.31; 95% CI, 1.12-1.52) than former smokers (1.06; 95% CI, 0.93-1.22). Current heavy smoking (> or = 36 pack-years) was associated with a 45% increased OR for follicular lymphoma (1.45; 95% CI, 1.15-1.82) compared with nonsmokers.

CONCLUSIONS

Cigarette smoking may increase the risk of developing follicular lymphoma but does not seem to affect risk of the other non-Hodgkin lymphoma subtypes we examined. Future research is needed to determine the biological mechanism responsible for our subtype-specific results.

Transitions between states of disability and independence among older persons

The objectives of this prospective cohort study, conducted in New Haven, Connecticut, from 1998 to 2004, were to describe disability states experienced by older persons, to evaluate the rate of transitions between states and the duration of disability episodes, and to determine whether these findings differ on the basis of physical frailty--a condition of low physical capacity and vulnerability to adverse functional outcomes. Participants included 754 persons aged 70 years or older who were initially independent in four key activities of daily living: bathing, dressing, walking, or transferring. Disability was assessed during monthly telephone interviews for a median of 60 months, and participants were classified each month according to the following four states: no disability, mild disability (one or two activities), severe disability (three or four activities), and death. Transitions between states of disability and independence were common, with a majority of both frail and nonfrail participants experiencing at least one transition. The rate of transitions varied greatly among individuals. Nonfrail participants had lower rates of transition from less to more disability, higher rates of transition from more to less disability, and slightly shorter durations of disability. To fully understand the disabling process, investigators and clinicians must consider the episodic and recurrent nature of disability.

Effect of Climate Change on Lyme Disease Risk in North America

An understanding of the influence of climate change on Ixodes scapularis, the main vector of Lyme disease in North America, is a fundamental component in assessing changes in the spatial distribution of human risk for the disease. We used a climate suitability model of I. scapularis to examine the potential effects of global climate change on future Lyme disease risk in North America. A climate-based logistic model was first used to explain the current distribution of I. scapularis in North America. Climate change scenarios were then applied to extrapolate the model in time and produce forecasts of vector establishment. The spatially modeled relationship between I. scapularis presence and large-scale environmental data generated the current pattern of I. scapularis across North America with an accuracy of 89% (p<0.0001). Extrapolation of the model revealed a significant expansion of I. scapularis north into Canada with an increase in suitable habitat of 213% by the 2080's. Climate change will also result in a retraction of the vector from southern United States, and movement into the central United States. This report predicts the effect of climate change on Lyme disease risk and specifically forecasts the emergence of a tick-borne infectious disease in Canada. Our modeling approach could thus be used to outline where future control strategies and prevention efforts need to be applied.

Breast cancer risk factors according to joint estrogen receptor and progesterone receptor status

BACKGROUND

We investigated risk factor patterns for subtypes of breast cancer characterized by joint estrogen receptor (ER) and progesterone receptor (PR) status in a hospital-based case-control study.

METHODS

ER and PR tumor status were determined immunohisotchemically. Risk factors of interest were entered into a multiple polychotomous logistic regression model simultaneously; odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Using this model, cases in the four tumor subtypes (ER+PR+, ER-PR-, ER+PR-, ER-PR+) were compared simultaneously to controls. A Wald test for heterogeneity across the four subtypes was conducted, as well as a case-case comparison between the two most biologically disparate subtypes, ER+PR+ and ER-PR-.

RESULTS

The receptor status distribution was as follows: 33% ER+PR+, 34% ER-PR-, 20% ER+PR-, and 13% ER-PR+. Among 317 cases and 401 controls, we found significant heterogeneity across the four tumor subtypes for older age at first full-term pregnancy (p=0.04) and post-menopausal status (p=0.04). For older age at first full-term pregnancy, an elevated risk was found for the ER+PR- subtype (OR=2.5; 95% CI: 1.2-5.1). For post-menopausal status, elevated risks were found for both the ER+PR+ (OR=2.4; 95% CI: 1.1-4.9) and ER+PR- (OR=7.2; 95% CI: 2.4-21.7) subtypes. From the case-case comparisons, we found that cases, who had consumed alcohol for more than 1 year were 3.4 times more likely to have ER+PR+ tumors than ER-PR- tumors (95% CI: 1.4-8.4).

CONCLUSIONS

Certain breast cancer risk factors may vary by ER and PR status, and joint ER/PR status should be taken into account in future studies of risk factor estimates.

Serum polychlorinated biphenyls, cytochrome P-450 1A1 polymorphisms, and risk of breast cancer in Connecticut women

Recent epidemiologic studies have suggested that genetic polymorphisms in the cytochrome P-450 1A1 gene (CYP1A1) may affect the relation between environmental exposure to polychlorinated biphenyls (PCBs) and breast cancer risk. The authors report results from a case-control study evaluating the potential effect of gene-environment interaction between CYP1A1 and serum PCB levels on breast cancer risk among Caucasian women in Connecticut. The study included 374 case women with histologically confirmed breast cancer and 406 noncancerous controls with information on both serum PCB level and CYP1A1 genotype (1999-2002). Compared with women who had the homozygous wild-type CYP1A1 m2 genotype, significantly increased risks of breast cancer were found for women with the CYP1A1 m2 variant genotype (odds ratio (OR) = 2.1, 95% confidence interval (CI): 1.1, 3.9), especially postmenopausal women (OR = 2.4, 95% CI: 1.1, 5.0). Risks associated with the CYP1A1 m2 variant genotype were highest for all women (OR = 3.6, 95% CI: 1.5, 8.2) and postmenopausal women (OR = 4.3, 95% CI: 1.6, 12.0) with higher serum PCB levels (611-2,600 ng/g). The CYP1A1 m1 and m4 genotypes were not associated with breast cancer risk independently or in combination with PCB exposure. In summary, the CYP1A1 m2 genetic polymorphism was associated with increased risk of female breast cancer and may modify the relation between PCB exposure and breast cancer risk.

Polychlorinated biphenyls and breast cancer risk by combined estrogen and progesterone receptor status

Studies have suggested that breast cancer risk factor profiles may vary according to joint estrogen receptor (ER) and progesterone receptor (PR) tumor status. Most of the published literature to date which has investigated the association between exposure to organochlorine compounds and breast cancer has reported null or weak associations. If, indeed, the classification by hormonal receptor status identifies different forms of breast cancer, then assessing the risk of exposure to polychlorinated biphenyls (PCBs) on breast cancer as one disease or stratifying based on ER or PR status alone may obscure the association between PCBs and breast cancer. A hospital-based case-control study of 266 cases and 347 benign breast disease controls was conducted to examine the association of blood serum and adipose tissue concentrations of PCBs with breast cancer by joint ER/PR status. Total PCBs were measured in blood serum, and the following PCB congeners were measured in breast adipose tissue: 74, 118, 138, 153, 156, 170, 180, 183, 187. We did not detect any clear relationship or change in breast cancer risk based on joint ER/PR tumor status for body burden of PCBs, whether measured in blood serum or breast adipose tissue, by total PCBs or for specific congeners. These results confirm previous findings in the literature of no positive association between environmental exposure to PCBs and risk of breast cancer.

Hospitalization, restricted activity, and the development of disability among older persons

CONTEXT

Preventing the development of disability in activities of daily living is an important goal in older adults, yet relatively little is known about the disabling process.

OBJECTIVES

To evaluate the relationship between 2 types of intervening events (hospitalization and restricted activity) and the development of disability and to determine whether this relationship is modified by the presence of physical frailty.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study, conducted in the general community in greater New Haven, Conn, from March 1998 to March 2003, of 754 persons aged 70 years or older, who were not disabled (ie, required no personal assistance) in 4 essential activities of daily living: bathing, dressing, walking inside the house, and transferring from a chair. Participants were categorized into 2 groups according to the presence of physical frailty (defined on the basis of slow gait speed) and were followed up with monthly telephone interviews for up to 5 years to ascertain exposure to intervening events and determine the occurrence of disability.

MAIN OUTCOME MEASURE

Disability, defined as the need for personal assistance in bathing, dressing, walking inside the house, or transferring from a chair.

RESULTS

During the 5-year follow-up period, disability developed among 417 (55.3%) participants, 372 (49.3%) were hospitalized and 600 (79.6%) had at least 1 episode of restricted activity. The multivariable hazard ratios for the development of disability were 61.8 (95% confidence interval [CI], 49.0-78.0) within a month of hospitalization and 5.54 (95% CI, 4.27-7.19) within a month of restricted activity. Strong associations were observed for participants who were physically frail and those who were not physically frail. Hospital admissions for falls were most likely to lead to disability. Intervening events occurring more than a month prior to disability onset were not associated with the development of disability. The population-attributable fractions associated with new exposure to hospitalization and restricted activity, respectively, were 0.48 and 0.19; 0.40 and 0.20, respectively, for frail participants and 0.61 and 0.16, respectively, for nonfrail participants.

CONCLUSIONS

Illnesses and injuries leading to either hospitalization or restricted activity represent important sources of disability for older persons living in the community, regardless of the presence of physical frailty. These intervening events may be suitable targets for the prevention of disability.

Strategies for identifying pregnancies in the automated medical records of the General Practice Research Database

PURPOSE

To develop a method for identifying the beginning and ending records of pregnancies in the automated medical records of the General Practice Research Database (GPRD).

METHODS

Women's records from 1991 to 1999 were searched for codes from 17 pregnancy marker and 7 pregnancy outcome categories. Using the retrieved records, all possible pregnancy marker-outcome combinations were formed per woman. For each combination, the difference in days between record event dates was calculated. Restrictions were applied to select the combination with the earliest pregnancy marker mapped to the first outcome for each pregnancy. Iterations of the algorithm identified multiple pregnancies per woman when present. The algorithm was evaluated by analyzing time between marker and outcome event dates of mapped pregnancies and by analyzing unmapped pregnancy markers and outcomes.

RESULTS

A total of 297,082 pregnancies were identified: 80% by general practitioner (GP) visit codes as the earliest pregnancy marker and 14% by laboratory or procedure codes. Limiting pregnancies to one per woman aged 15-44 years yielded 209,266 pregnancies. Pregnancy mapping success was greater than 80%. Plotting the pregnancies by weeks from earliest pregnancy marker to outcome and by pregnancy marker category showed two peaks in the distribution: 2-3 weeks and 33 weeks.

CONCLUSIONS

Arranging codes and time into algorithms provides a useful tool for pregnancy identification in databases whose size prohibits the audit of printed records. Evaluation of our algorithm confirmed a high degree of mapping success and a sensible time distribution from pregnancy marker to outcome.

Menstrual and reproductive factors and risk of non-Hodgkin's lymphoma among Connecticut women

Several recent studies have suggested a potential role of menstrual and reproductive factors in the risk of non-Hodgkin's lymphoma. To further examine the relation, the authors analyzed data from a population-based case-control study of non-Hodgkin's lymphoma in Connecticut women between 1996 and 2000. A total of 601 histologically confirmed cases and 717 randomly selected population-based controls were included in this study. An in-person interview was conducted using a standardized and structured questionnaire to collect information on menstrual and reproductive factors and potential confounding factors. Compared with nulliparous women, women who had four or more pregnancies during their lifetime were found to have a significantly reduced risk of non-Hodgkin's lymphoma (odds ratio (OR) = 0.6, 95% confidence interval (CI): 0.4, 0.9). Risk appeared to decrease with increasing number of pregnancies (p(trend) = 0.03). The authors also observed an increased risk of non-Hodgkin's lymphoma overall (OR = 1.5, 95% CI: 1.0, 2.2) and of diffuse non-Hodgkin's lymphoma (OR = 1.7, 95% CI: 1.1, 2.7) for women who started their first menstrual period at age 15 or more years compared with those who started their first menstrual period before age 12 years. These findings support a reduced risk of non-Hodgkin's lymphoma associated with multiple pregnancies and an increased risk of non-Hodgkin's lymphoma associated with later age at menarche.

The development of insidious disability in activities of daily living among community-living older persons

PURPOSE

To determine how often disability in essential activities of daily living develops insidiously, and to evaluate whether the likelihood of insidious disability differs on the basis of physical frailty.

METHODS

We conducted a prospective study of 754 nondisabled, community-living persons aged 70 years or older. Participants were categorized according to the presence or absence of physical frailty, which was defined on the basis of gait speed. Participants were subsequently followed with monthly telephone interviews for 3 years to determine the occurrence of disability in bathing, dressing, walking, or transferring, and to ascertain exposure to precipitating events, which included acute hospital admissions and other illnesses, injuries, or problems leading to restricted activity.

RESULTS

For first episodes of disability, 73 (36%) of 203 developed insidiously among the 322 participants who were physically frail and 26 (18%) of 141 developed insidiously among the 432 participants who were not physically frail (P <0.001). Physical frailty was the only factor that was associated significantly with the development of insidious disability, with an adjusted odds ratio of 2.4 (95% confidence interval: 1.4 to 4.1). The likelihood that an episode of disability was insidious increased progressively, from 29% of the 344 first episodes to 65% of the 155 fourth or higher episodes (P for trend <0.001).

CONCLUSION

Disability in essential activities of daily living often occurs insidiously, particularly among older persons who are physically frail or who have had prior episodes of disability.

Prior medical conditions and medication use and risk of non-Hodgkin lymphoma in Connecticut United States women

OBJECTIVE

To further investigate the role of prior medical conditions and medication use in the etiology of non-Hodgkin lymphoma (NHL), we analyzed the data from a population-based case-control study of NHL in Connecticut women.

METHODS

A total of 601 histologically confirmed incident cases of NHL and 717 population-based controls were included in this study. In-person interviews were administered using standardized, structured questionnaires to collect information on medical conditions and medication use.

RESULTS

An increased risk was found among women who had a history of autoimmune disorders (such as rheumatoid arthritis, lupus erythematosus, Sjogren's syndrome, and multiple sclerosis), anemia, eczema, or psoriasis. An increased risk was also observed among women who had used steroidal anti-inflammatory drugs and tranquilizers. A reduced risk was found for women who had scarlet fever or who had used estrogen replacement therapy, aspirin, medications for non-insulin dependent diabetes, HMG-CoA reductase inhibitors, or beta-adrenergic blocking agents. Risk associated with past medical history appeared to vary based on NHL subtypes, but the results were based on small number of exposed subjects.

CONCLUSION

A relationship between certain prior medical conditions and medication use and risk of NHL was observed in this study. Further studies are warranted to confirm our findings.

Blood transfusion and risk of non-Hodgkin's lymphoma in Connecticut women

The incidence and mortality rates of non-Hodgkin's lymphoma have been increasing worldwide. Allogeneic blood transfusion has been suggested as a risk factor for non-Hodgkin's lymphoma, but the results from epidemiologic studies have been inconsistent. Data from a population-based case-control study of Connecticut women were analyzed to evaluate this relation. A total of 601 histologically confirmed, non-Hodgkin's lymphoma incident cases identified between 1996 and 2000 and 717 randomly selected controls were included in this study. Allogeneic blood transfusion was not associated with the increased risk of non-Hodgkin's lymphoma overall (odds ratio = 1.0, 95% confidence interval: 0.7, 1.3) or by subtype of the disease. The risk also did not vary by number of allogeneic blood transfusions, age at first transfusion, or time since first transfusion. When the reason for blood transfusion was considered, an increased risk of non-Hodgkin's lymphoma was found only for allogeneic blood transfusion for reason of anemia. In summary, the authors' findings do not support the hypothesis that allogeneic blood transfusion increases the risk of non-Hodgkin's lymphoma.

Enhancing West Nile virus surveillance, United States

We provide a method for constructing a county-level West Nile virus risk map to serve as an early warning system for human cases. We also demonstrate that mosquito surveillance is a more accurate predictor of human risk than monitoring dead and infected wild birds.

Hepatitis C virus and risk of non-Hodgkin lymphoma: a population-based case-control study among Connecticut women

OBJECTIVES

Previous epidemiologic studies of hepatitis C virus (HCV) infection and B-cell non-Hodgkin lymphoma (B-NHL) have yielded conflicting results, perhaps due to differences in the classification of B-NHL and the choice of non-population-based control groups that may not reflect the background population prevalence of HCV. To further investigate the link between HCV and NHL, we conducted HCV testing on serum samples of 998 women (464 cases; 534 controls) from a population-based case-control study of women in Connecticut.

METHODS

Serum samples were screened for HCV antibodies using an enzyme immunoassay; positive samples were confirmed by additional testing for HCV antibodies and for serum HCV RNA.

RESULTS

Approximately 2% (8 of 464) of cases and 1% (5 of 534) of controls tested positive for HCV. The risk of NHL associated with HCV infection appeared to be concentrated among B-cell lymphomas [odds ratio (OR) 2.0; 95% confidence interval (CI) 0.6, 8.2], particularly among follicular lymphomas (OR 4.1, 95% CI 0.8, 19.4).

CONCLUSIONS

The primary strength of this study is our use of a population-based study design, although the low prevalence of HCV among women in Connecticut resulted in wide CIs for the estimated association between HCV and B-NHL subtypes. Our study suggests that HCV may be associated with increased risk of development of B-NHL, and that this risk may vary by B-NHL subtype among women. Due to the relatively low prevalence of HCV in our study population and the scarcity of population-based epidemiological research on this subject, our study highlights the need for additional large, population-based studies of the role of HCV in the etiology of B-NHL.

Hepatitis C Virus and Risk of Non-Hodgkin Lymphoma: A Population-Based Case-Control Study among Connecticut Women

Objective: Previous epidemiologic studies of hepatitis C virus (HCV) infection and B-cell non-Hodgkin lymphoma (B-NHL) have yielded conflicting results, perhaps due to differences in the classification of B-NHL and the choice of non-population-based control groups that may not reflect the background population prevalence of HCV. To further investigate the link between HCV and NHL, we conducted HCV testing on serum samples of 998 women (464 cases; 534 controls) from a population-based case-control study of women in Connecticut. Methods: Serum samples were screened for HCV antibodies using an enzyme immunoassay; positive samples were confirmed by additional testing for HCV antibodies and for serum HCV RNA. Results: Approximately 2% (8 of 464) of cases and 1% (5 of 534) of controls tested positive for HCV. The risk of NHL associated with HCV infection appeared to be concentrated among B-cell lymphomas [odds ratio (OR) 2.0; 95% confidence interval (CI) 0.6, 8.2], particularly among follicular lymphomas (OR 4.1, 95% CI 0.8, 19.4). Conclusion: The primary strength of this study is our use of a population-based study design, although the low prevalence of HCV among women in Connecticut resulted in wide CIs for the estimated association between HCV and B-NHL subtypes. Our study suggests that HCV may be associated with increased risk of development of B-NHL, and that this risk may vary by B-NHL subtype among women. Due to the relatively low prevalence of HCV in our study population and the scarcity of population-based epidemiological research on this subject, our study highlights the need for additional large, population-based studies of the role of HCV in the etiology of B-NHL.

Diet and nutrient intakes and risk of non-Hodgkin's lymphoma in Connecticut women

A population-based case-control study (601 cases and 717 controls) was conducted in 1995-2001 among Connecticut women to evaluate the relation between diet and nutrient intakes and the risk of non-Hodgkin's lymphoma (NHL). When the highest quartile of intake was compared with the lowest, the authors found an increased risk of NHL associated with animal protein (odds ratio = 1.7, 95% confidence interval: 1.2, 2.4) and saturated fat (odds ratio = 1.9, 95% confidence interval: 1.1, 2.3) but a reduced risk for polyunsaturated fat (odds ratio = 0.6, 95% confidence interval: 0.4, 0.9) and no relation for vegetable protein and monounsaturated fat. An increased risk was also observed for higher intakes of retinol, eggs, and dairy products. On the other hand, a reduced risk was found for higher intakes of dietary fiber and for several fruit and vegetable items. Risk of NHL associated with diet and nutrient intakes appeared to vary based on NHL subtype. An association between dietary intake and NHL risk is biologically plausible because diets high in protein and fat may lead to altered immunocompetence, resulting in an increased risk of NHL. The antioxidant or inhibiting nitrosation reaction properties of vegetables and fruits may result in a reduced risk. Further investigation of the role of dietary intakes on the risk of NHL is warranted.

Alcohol use and risk of non-Hodgkin's lymphoma among Connecticut women (United States)

OBJECTIVE

Incidence rates of non-Hodgkin's lymphoma (NHL) have risen dramatically over the past several decades; however, the etiology of NHL remains largely unknown. Previous studies of the relationship between alcohol consumption and NHL have yielded conflicting results. Data from a population-based case-control study among women in Connecticut were analyzed to determine the potential impact of alcohol consumption on risk of NHL.

METHODS

The study included 601 histologically confirmed, incident cases of NHL and 718 population-based controls. In-person interviews were administered using standardized, structured questionnaires to collect data on history of consumption for beer, wine, and liquor.

RESULTS

When compared to non-drinkers, women who reported consumption of at least 12 drinks per year of any type of alcohol experienced slightly reduced risk of NHL (OR: 0.82; 95% CI: 0.65-1.04). Further stratification by alcohol type revealed that the inverse association was mainly limited to wine consumption (OR: 0.75; 95% CI: 0.59-0.96), with no clear association for beer or liquor consumption. Risk of NHL was further reduced with increasing duration of wine consumption (p for linear trend = 0.02). Consumption of wine for greater than 40 years was associated with approximately 40% reduction in risk (OR: 0.63; 95% CI: 0.44-0.91).

CONCLUSION

Our results are consistent with several recent epidemiologic studies that have also suggested an inverse association between wine consumption and risk of NHL. The reduction in risk of NHL associated with increased duration of wine consumption warrants further investigation in other populations.

Hair-coloring product use and risk of non-Hodgkin's lymphoma: a population-based case-control study in Connecticut

A population-based case-control study was conducted in Connecticut in 1996-2002 to test the hypothesis that lifetime hair-coloring product use increases non-Hodgkin's lymphoma risk. A total of 601 histologically confirmed incident female cases and 717 population-based controls were included in the study. An increased risk of non-Hodgkin's lymphoma was observed among women who reported use of hair-coloring products before 1980 (odds ratio = 1.3, 95% confidence interval (CI): 1.0, 1.8). The odds ratios were 2.1 (95% CI: 1.0, 4.0) for those using darker permanent hair-coloring products for more than 25 years and 1.7 (95% CI: 1.0, 2.8) for those who had more than 200 applications. Follicular type, B-cell, and low-grade lymphoma generally showed an increased risk. On the other hand, the authors found no increased risk of non-Hodgkin's lymphoma overall and by subtype of exposure and disease among women who started using hair-coloring products in 1980 or later. It is currently unknown why an increased risk of non-Hodgkin's lymphoma was found only among women who started using hair-coloring products before 1980. Further studies are warranted to show whether the observed association reflects the change in hair dye formula contents during the past two decades or indicates that recent users are still in their induction and latent periods.

Cigarette smoking and risk of non-Hodgkin lymphoma subtypes among women

Previous studies of the relationship between cigarette smoking and non-Hodgkin lymphoma (NHL) have yielded conflicting results, perhaps because most studies have evaluated the risk for all NHL subtypes combined. Data from a population-based case–control study conducted among women in Connecticut were used to evaluate the impact of cigarette smoking on the risk of NHL by histologic type, tumour grade, and immunologic type. A total of 601 histologically confirmed, incident cases of NHL and 718 population-based controls provided in-person interviews. A standardised, structured questionnaire was used to collect information on each subject's current smoking status, age at initiation, duration and intensity of smoking, and cumulative lifetime exposure to smoking. Our data suggest that cigarette smoking does not alter the risk of all NHL subtypes combined. However, increased risk of follicular lymphoma appears to be associated with increased intensity and duration of smoking, and cumulative lifetime exposure to smoking. Compared with nonsmokers, women with a cumulative lifetime exposure of 16–33 pack-years and 34 pack-years or greater experience 50% increased risk (OR=1.5, 95% CI 0.9–2.5) and 80% increased risk (OR=1.8, 95% CI 1.1–3.2), respectively, of follicular lymphoma (P for linear trend=0.05). Our study findings are consistent with several previous epidemiologic studies suggesting that cigarette smoking increases the risk of follicular lymphoma. This research highlights the importance of distinguishing between NHL subtypes in future research on the aetiology of NHL.

Association of low-level ozone and fine particles with respiratory symptoms in children with asthma

CONTEXT

Exposure to ozone and particulate matter of 2.5 microm or less (PM2.5) in air at levels above current US Environmental Protection Agency (EPA) standards is a risk factor for respiratory symptoms in children with asthma.

OBJECTIVE

To examine simultaneous effects of ozone and PM2.5 at levels below EPA standards on daily respiratory symptoms and rescue medication use among children with asthma.

DESIGN, SETTING, AND PARTICIPANTS

Daily respiratory symptoms and medication use were examined prospectively for 271 children younger than 12 years with physician-diagnosed, active asthma residing in southern New England. Exposure to ambient concentrations of ozone and PM2.5 from April 1 through September 30, 2001, was assessed using ozone (peak 1-hour and 8-hour) and 24-hour PM2.5. Logistic regression analyses using generalized estimating equations were performed separately for maintenance medication users (n = 130) and nonusers (n = 141). Associations between pollutants (adjusted for temperature, controlling for same- and previous-day levels) and respiratory symptoms and use of rescue medication were evaluated.

MAIN OUTCOME MEASURES

Respiratory symptoms and rescue medication use recorded on calendars by subjects' mothers.

RESULTS

Mean (SD) levels were 59 (19) ppb (1-hour average) and 51 (16) ppb (8-hour average) for ozone and 13 (8) microg/m3 for PM2.5. In copollutant models, ozone level but not PM2.5 was significantly associated with respiratory symptoms and rescue medication use among children using maintenance medication; a 50-ppb increase in 1-hour ozone was associated with increased likelihood of wheeze (by 35%) and chest tightness (by 47%). The highest levels of ozone (1-hour or 8-hour averages) were associated with increased shortness of breath and rescue medication use. No significant, exposure-dependent associations were observed for any outcome by any pollutant among children who did not use maintenance medication.

CONCLUSION

Asthmatic children using maintenance medication are particularly vulnerable to ozone, controlling for exposure to fine particles, at levels below EPA standards.

A climate-based model predicts the spatial distribution of the Lyme disease vector Ixodes scapularis in the United States

An understanding of the spatial distribution of the black-legged tick, Ixodes scapularis, is a fundamental component in assessing human risk for Lyme disease in much of the United States. Although a county-level vector distribution map exists for the United States, its accuracy is limited by arbitrary categories of its reported presence. It is unknown whether reported positive areas can support established populations and whether negative areas are suitable for established populations. The steadily increasing range of I. scapularis in the United States suggests that all suitable habitats are not currently occupied. Therefore, we developed a spatially predictive logistic model for I. scapularis in the 48 conterminous states to improve the previous vector distribution map. We used ground-observed environmental data to predict the probability of established I. scapularis populations. The autologistic analysis showed that maximum, minimum, and mean temperatures as well as vapor pressure significantly contribute to population maintenance with an accuracy of 95% (p < 0.0001). A cutoff probability for habitat suitability was assessed by sensitivity analysis and was used to reclassify the previous distribution map. The spatially modeled relationship between I. scapularis presence and large-scale environmental data provides a robust suitability model that reveals essential environmental determinants of habitat suitability, predicts emerging areas of Lyme disease risk, and generates the future pattern of I. scapularis across the United States.

Dietary (n-3)/(n-6) fatty acid ratio: possible relationship to premenopausal but not postmenopausal breast cancer risk in U.S. women

Recent research has suggested that an increased (n-3) fatty acid intake and/or increased (n-3)/(n-6) polyunsaturated fatty acid (PUFA) ratio in the diet is associated with a lower breast cancer risk. This case-control study investigated the association between intake of (n-3) and other fatty acids and the (n-3)/(n-6) PUFA ratio and breast cancer risk. After combining data from two related case-control studies in Connecticut, we had information available on a total of 1119 women (565 cases and 554 controls). Cases were all histologically confirmed, incident breast carcinoma patients. Controls were hospital-based (Yale-New Haven Hospital study site) and population-based (Tolland County study site). Information on dietary intake was obtained through a validated food-frequency questionnaire. Standard multivariate methods were used to address the independent effects of specific fatty acids, fat classes and macronutrients on breast cancer risk. In the full study population, there were no significant trends for any macronutrient/fatty acid when comparing the highest to the lowest quartile of intake. When the analysis was restricted to premenopausal women, consumption of the highest compared with the lowest quartile of the (n-3)/(n-6) PUFA ratio was associated with a nonsignificant 41% lower risk of breast cancer [odds ratio (OR) = 0.59, 95% confidence interval (CI) 0.29, 1.19, P for trend = 0.09]. A higher (n-3)/(n-6) PUFA ratio was significantly associated with a lower risk of breast cancer when the data were restricted to the Tolland County (population-based) study site; OR = 0.50, 95% CI 0.27, 0.95, P for trend = 0.02. These results are consistent with the hypothesis that a higher (n-3)/(n-6) PUFA ratio may reduce the risk of breast cancer, especially in premenopausal women.

A case-control study of occupation and breast-cancer risk in Connecticut

BACKGROUND

Several occupations have recently been related to breast-cancer. The results, however, are inconsistent. We analyse data from a case-control study of breast cancer in Connecticut conducted in 1994-97 to further examine the potential relationship between occupation and breast-cancer risk.

METHODS

A total of 608 breast-cancer cases and 609 controls, 31-85 years old, were included in the study. Information regarding occupation and other breast-cancer risk-factors was obtained through in-person interviews by trained interviewers, using a standardised, structured questionnaire.

RESULTS

after adjustment for major breast-cancer risk-factors, a significantly increased risk of breast cancer was observed for teachers and librarians [odds ratio (OR), = 1.9, 95% confidence interval (CI) 1.3-2.7]. A significantly reduced risk, on the other hand, was observed for technicians and related supports (OR = 0.5, 95% CI 0.3-0.9). No other occupational groups showed a significant association with breast-cancer risk.

CONCLUSIONS

The observed increase in breast-cancer risk among teachers and librarians is consistent with most earlier studies. It is currently unknown, however, what factors may explain the observed increase. Considering that teachers and librarians represent one of the largest single occupational groups among employed US women, further investigation of this association is warranted.

Glutathione S-transferase M1 and T1 genetic polymorphisms, alcohol consumption and breast cancer risk

Alcohol consumption has been inconsistently associated with breast cancer risk. Recent studies suggest that genetic polymorphisms of glutathione S-transferases (GSTs) may modify this relation. To determine if breast cancer risk is associated with GSTM1 and GSTT1 genetic polymorphisms, and to evaluate the effect modification between GST genotypes and alcohol consumption in the risk of breast cancer, we conducted a case-control study in the state of Connecticut in the period 1998 and 2001. Cases were histologically confirmed, incident breast cancer patients in New Haven County, CT. Controls were randomly selected from women histologically confirmed to be without breast cancer. The study results show that, while GSTM1 genotypes were not associated with breast cancer risk, GSTT1-null genotype was associated with a significant 90% increased risk for postmenopausal women (OR=1.9, 95% CI 1.2-3.0). Analysis by GST genotypes and alcohol consumption shows that GSTM1A ever-drinking women had a 2.5-fold (OR=2.5, 95% CI 1.1-5.5) increased risk of breast cancer compared to the GSTM1A never-drinkers, and the risk increases with duration and daily amount of alcohol consumption. Postmenopausal women with GSTT1-null genotype, who consumed a lifetime of >250 kg of spirit-equivalents, had an almost seven-fold increased risk (OR=6.8, 95% CI 1.4-33.9), and drinking commencing at younger ages appears to carry a higher risk. An OR of 8.2 (95% CI 1.2-57.4) was observed for those with GSTM1A, and GSTT1-null genotypes who had consumed a lifetime of >250 kg of spirit-equivalents. In conclusion, alcohol consumption may increase breast cancer risk among those who carry susceptible GST genotypes.

Levels of household mold associated with respiratory symptoms in the first year of life in a cohort at risk for asthma

We assessed prospectively the risk of increased incidence of respiratory symptoms after exposure to particular fungal genera in a susceptible population--namely, infants (n = 880) at high risk for developing asthma. Days of wheeze or persistent cough, information on maternal allergy and asthma, socioeconomic variables, and housing characteristics were collected over the course of the infant's first year of life. Exposure to mold was assessed by airborne samples collected at one time early in the infant's life. Fungi were identified to genus level, recorded as colony-forming units per cubic meter (CFU/m3), and then categorized into four levels: 0 (undetectable), 1-499 CFU/m3 (low), 500-999 CFU/m3 (medium), and greater than or equal to 1,000 CFU/m3 (high). Effects of mold on wheeze and persistent cough, adjusting for potential confounding factors, were examined with Poisson regression analyses. The two most commonly found genera were Cladosporium (in 62% of the homes) and Penicillium (41%). Cladosporium was associated with reported mold (p < 0.02) and water leaks (p < 0.003). Rate of persistent cough was associated with reported mold [Rate ratio (RR) = 1.49; 95% CI, 1.18-1.88]. The highest level of Penicillium was associated with higher rates of wheeze (RR = 2.15; 95% CI, 1.34-3.46) and persistent cough (RR = 2.06; 95% CI, 1.31-3.24) in models controlling for maternal history of asthma and allergy, socioeconomic status, season of mold sample, and certain housing characteristics. We conclude that infants in this high-risk group who are exposed to high levels of Penicillium are at significant risk for wheeze and persistent cough.

Infant respiratory symptoms associated with indoor heating sources

This study examined the effects of indoor heating sources on infant respiratory symptoms during the heating season of the first year of life. Mothers delivering babies between 1993 and 1996 at 12 hospitals in Connecticut and Virginia were enrolled. Daily symptom and heating source use information about their infant was obtained every 2 weeks during the first year of life. Heating sources included fireplace, wood stove, kerosene heater, and gas space heater use. Four health outcomes were analyzed by reporting period: days of wheeze, episodes of wheeze, days of cough, and episodes of cough. A large percentage of infants had at least one episode of cough (88%) and wheeze (33%) during the heating season of the first year of life. Wood stove, fireplace, kerosene heater, and gas space heater use was intermittent across the study period. In adjusted Poisson regression models controlling for important confounders, gas space heater use was associated with episodes and days of wheeze. Wood stove use was associated with total days of cough, and kerosene heater use was associated with episodes of cough. Fireplace use was not associated with any of the respiratory symptoms. Use of some heating sources appears related to respiratory symptoms in infants.

Use of hair colouring products and breast cancer risk: a case-control study in Connecticut

This case-control study was designed to test the hypothesis that the risk of breast cancer varies by type and colour of the hair colouring products used. A total of 608 cases and 609 controls were included in the study. We found no increased risk associated with the overall use of hair dye products or exclusive use of permanent or temporary types of hair dye products. Among those who reported to have exclusively used semi-permanent types of hair colouring products, some of the ORs were elevated. However, none of the ORs related to age at first use, duration of use, total number of applications, and years since first use, was statistically significant. There was also no increased risk of breast cancer associated with exclusive use of dark or light hair colouring products, or use of mixed types or colours of hair dye products. We also found no increased risk of breast cancer associated with hair dye use based on an individual's reason for using a hair colouring product, such as to cover grey or to change natural hair colour. These data suggest that the use of hair colouring products does not have a major impact on the risk of breast cancer.

Radiation exposure from diagnostic and therapeutic treatments and risk of breast cancer

An association between low-dose diagnostic X-ray exposure or therapeutic radiation treatment and breast cancer risk has not been established. To further investigate the issue, we analysed data from a case-control study of breast cancer in Connecticut in 1994-1997. A total of 1217 subjects (608 breast cancer cases and 609 controls), 30-80 years old, participated in the study. A standardized, structured questionnaire was used to collect information through in-person interviews on diagnostic or therapeutic radiation and other breast cancer risk factors. An odds ratio (OR) of 1.7 (95% confidence interval (CI) 0.8-3.6) was observed for postmenopausal women with therapeutic radiation treatment for skin problems such as ringworm and acne, and an OR of 2.5 (95% CI 1.0-6.8) for those who reported having been treated six or more times. Radiation treatment received at younger ages seems to carry a higher risk. In earlier studies therapeutic radiation for skin problems has been associated with an increased risk of breast cancer. Therefore, it is possible that scattered radiation from these treatments could increase the risk of breast cancer. Radiation exposure from diagnostic X-rays was not associated with a significantly increased risk of breast cancer in this study.

Interpreting conflicting findings from clinical trials of auricular acupuncture for cocaine addiction: does treatment context influence outcome?

OBJECTIVE

To compare findings from two consecutive clinical trials of auricular acupuncture for cocaine addiction conducted at the same site in order to explore consistency of treatment effects.

SUBJECTS

One hundred and sixty-five (165) cocaine-dependent, methadone-maintained patients (study 1, n = 82; study 2, n = 83).

INTERVENTIONS

Subjects in both studies were randomly assigned to auricular acupuncture, a needle insertion control condition, or a no-needle relaxation control. Treatment sessions were offered five times weekly for 8 weeks. The two studies were equivalent in design, except that unlike study 1, study 2 offered subject payments for attendance and did not include weekly group counseling.

OUTCOME MEASURES

Cocaine use assessed by three times weekly urine screens constituted the primary outcome. Secondary measures included retention in treatment, treatment attendance, treatment credibility, therapeutic alliance, and acute effects of treatments.

RESULTS

Intent-to-treat analysis showed that patients assigned to acupuncture in study 1, but not in study 2, were significantly more likely to provide cocaine-negative urine samples relative to the two control conditions.

CONCLUSIONS

The positive effect for acupuncture found in study 1 was not found in study 2. Even though the two studies were similar, reasons for this inconsistency cannot be determined definitively, but may be because of differences in psychosocial context and payment contingencies between the two studies, or the lack of effectiveness of acupuncture in this application. The need to critically consider the influence of treatment context and other potential moderating variables on outcome in order to draw conclusions regarding treatment effectiveness is discussed.

Neurological and functional status 1 year after acute spinal cord injury: estimates of functional recovery in National Acute Spinal Cord Injury Study II from results modeled in National Acute Spinal Cord Injury Study III

OBJECT

In the second National Acute Spinal Cord Injury Study (NASCIS II) investigators evaluated several standard neurological parameters but not functional activity. This has led to questions concerning the clinical importance of the increase in neurological recovery observed following administration of methylprednisolone (MP) within 8 hours of acute spinal cord injury (SCI). The safety of the therapy has also been questioned.

METHODS

Both neurological and functional recovery were assessed in NASCIS III, a trial that followed an almost identical protocol to NASCIS II. In the current analysis locally weighted scatterplot smoothing (LOESS) nonparametric regression is used to model the extent of recovery in the Functional Independence Measure (FIM) that is predicted by improvement in the NASCIS/American Spinal Cord Injury Association motor scores that were documented in NASCIS III 1 year after SCI, and the models are applied to the extent of motor recovery demonstrated in NASCIS II. The models predict improvement in FIM that would be expected from the motor function recovery observed in NASCIS II. Estimates are provided overall and for patients with complete and incomplete neurological loss at time of injury. The authors review recent evidence obtained from randomized studies documenting adverse effects that may result from high-dose MP therapy. The relationship between motor function and FIM is strongly nonlinear and dependent on initial level of injury and degree of injury severity. In the best statistical model, the expanded motor score could be used to explain 77.2% of the variability in the FIM. Based on the mean MP-related 3.6-unit improvement in the motor score for patients with complete injuries and 7.3 for those with incomplete injuries owed to MP in NASCIS II, 18.6% of patients would improve six or more FIM points and 9% nine or more points, respectively. In those with complete neurological injury, the mean motor improvement of 3.6 predicted that 63.9% of the patients would improve three or more FIM points and 12.1% six or more points to a maximum of eight points. Of those with incomplete neurological injury, a 7.3 mean improvement in motor function predicted that 27.4% would gain six or more FIM points and that 21% would gain nine or more points to a maximum of 15 points. Analysis of the current best evidence from SCI and other randomized surgical trials in which high-dose MP has been administered provides no grounds for concern about commonly studied adverse effects.

CONCLUSIONS

The extent of MP therapy-related motor function recovery observed in NASCIS II predicted clinically important recovery in the FIM. Reasons to be cautious with regard to this prediction include the lack of robustness in statistical modeling, some loss of validity in the FIM, and considerable heterogeneity in the SCI population. Whatever functional activity is ascribed to high-dose MP therapy, it is does not appear to be associated with risk of adverse outcomes.

Restricted activity among community-living older persons: incidence, precipitants, and health care utilization

BACKGROUND

Restricted activity is a potentially important indicator of health and functional status. Yet, relatively little is known about the incidence, precipitants, or health care utilization associated with restricted activity among older persons.

OBJECTIVE

To more accurately estimate the rate of restricted activity among community-living older persons, to identify the health-related and non-health-related problems that lead to restricted activity, and to determine whether restricted activity is associated with increased health care utilization.

DESIGN

Prospective cohort study.

SETTING

New Haven, Connecticut.

PARTICIPANTS

754 nondisabled members of a large health plan, 70 years of age or older, who were categorized according to their risk for disability (low, intermediate, or high).

MEASUREMENTS

Occurrence of restricted activity (defined as having stayed in bed for at least half a day or having cut down on one's usual activities because of an illness, injury, or another problem), problems leading to restricted activity, and health care utilization were ascertained during monthly telephone interviews for up to 2 years.

RESULTS

In median follow-up of 15 months, 76.6% of participants reported restricted activity during at least 1 month and 39.3% reported restricted activity during 2 consecutive months. The rates of restricted activity per 100 person-months were 19.0 episodes for all participants and 16.9, 27.3, and 22.7 episodes for participants at low, intermediate, and high risk for disability, respectively. Of the 24 prespecified health-related and non-health-related problems, the rates per 100 person-months of restricted activity ranged from 0.1 episode for "problem with alcohol" to 65.5 episodes for "been fatigued." On average, participants identified 4.5 different problems as a cause for their restricted activity. Health care utilization was substantially greater during months with restricted activity than months without restricted activity. The corresponding rates per 100 person-months were 63.8 and 45.1 for physician office visits, 12.5 and 1.0 for emergency department visits, 14.1 and 0.3 for hospital admissions, and 67.6 and 45.1 for any health care utilization (P < 0.001 for each pairwise comparison).

CONCLUSIONS

Restricted activity is common among community-living older persons, regardless of risk for disability, and it is usually attributable to several concurrent health-related problems. Although restricted activity is associated with a substantial increase in health care utilization, older persons with restricted activity often do not seek medical attention.

The natural history of periodontal disease in man. Risk factors for progression of attachment loss in individuals receiving no oral health care

BACKGROUND

Few investigations have reported on risk factors for periodontal attachment loss over time in subjects with no home or professional dental care. The purpose of this report was to identify potential risk factors for progression of periodontal attachment loss among male Sri Lankan tea laborers who participated in a 20-year investigation of the natural history of periodontal disease.

METHODS

Data for this report were obtained from the 154 subjects who participated in the 1970 baseline and the final 1990 examinations and included data from their interim examinations performed in 1971, 1973, 1977, 1982, and 1985. Oral health assessments included: 1) attachment levels in millimeters on mesial and mesio-buccal surfaces of all but third molar teeth; 2) plaque index (PI); 3) gingival index (GI); 4) calculus index (CI); 5) caries index (DMFS); and 6) presence or absence of teeth. Other variables included age, history of smoking, and/or use of betel nut. Statistical analyses used multivariate repeated measures analysis of variance (ANOVA).

RESULTS

The final adjusted model indicated that attachment loss increased significantly with age (X2 = 74.0; df = 1), GI (X2 = 45.5; df = 1), CI (X2 = 52.7; df = 1) and follow-up time (X2 = 219.8; df = 6, P<0.0001 for all variables).

CONCLUSIONS

Age, GI, CI, and time were significantly associated with mean attachment loss over 20 years. Neither PI, history of smoking, or history of betel nut use were significantly associated with attachment loss over time.

Lactation and breast cancer risk: a case-control study in Connecticut

In this report, we examined the relationship between lactation and breast cancer risk, in a case-control study of breast cancer, conducted in Connecticut between 1994 and 1998. Included were 608 incident breast cancer cases and 609 age frequency matched controls, aged 30-80 years old. Cases and controls were interviewed by trained study interviewers, using a standardized, structured questionnaire, to obtain information on lactation and other major risk factors. Parous women who reported ever lactation had a borderline significantly reduced risk of breast cancer (OR = 0.83, 95% CI, 0.63-1.09). An OR of 0.53 (95% CI, 0.27-1.04) was observed in those having breastfed more than 3 children compared to those who never lactated. Women having breastfed their first child for more than 13 months had an OR of 0.47 (95% CI, 0.23-0.94) compared to those who never breastfed. Lifetime duration of lactation also showed a risk reduction while none of the ORs were statistically significant. Further stratification by menopausal status showed a risk reduction related to lactation for both pre- and postmenopausal women, while the relationship is less consistent for the latter. These results support an inverse association between breastfeeding and breast cancer risk.

1,1-Dichloro-2,2-bis(p-chlorophenyl)ethylene and Polychlorinated Biphenyls and Breast Cancer: Combined Analysis of Five U.S. Studies

BACKGROUND

Environmental exposure to organochlorines has been examined as a potential risk factor for breast cancer. In 1993, five large U.S. studies of women located mainly in the northeastern United States were funded to evaluate the association of levels of 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE) and polychlorinated biphenyls (PCBs) in blood plasma or serum with breast cancer risk. We present a combined analysis of these results to increase precision and to maximize statistical power to detect effect modification by other breast cancer risk factors.

METHODS

We reanalyzed the data from these five studies, consisting of 1400 case patients with breast cancer and 1642 control subjects, by use of a standardized approach to control for confounding and assess effect modification. We calculated pooled odds ratios (ORs) and 95% confidence intervals (CIs) by use of the random-effects model. All statistical tests were two-sided.

RESULTS

When we compared women in the fifth quintile of lipid-adjusted values with those in the first quintile, the multivariate pooled OR for breast cancer associated with PCBs was 0.94 (95% CI = 0.73 to 1.21), and that associated with DDE was 0.99 (95% CI = 0.77 to 1.27). Although in the original studies there were suggestions of elevated breast cancer risk associated with PCBs in certain groups of women stratified by parity and lactation, these observations were not evident in the pooled analysis. No statistically significant associations were observed in any other stratified analyses, except for an increased risk with higher levels of PCBs among women in the middle tertile of body mass index (25-29.9 kg/m(2)); however, the risk was statistically nonsignificantly decreased among heavier women.

CONCLUSIONS

Combined evidence does not support an association of breast cancer risk with plasma/serum concentrations of PCBs or DDE. Exposure to these compounds, as measured in adult women, is unlikely to explain the high rates of breast cancer experienced in the northeastern United States.

Oxychlordane and trans-nonachlor in breast adipose tissue and risk of female breast cancer

BACKGROUND

Organochlorine compounds, including organochlorine pesticides, have been suggested by some, but not all, studies to be associated with female breast-cancer risk. So far, studies relating organochlorine compounds and breast-cancer risk have mainly focused on polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) as risk factors for female breast cancer. This paper examines the hypothesis that environmental exposure to trans-nonachlor (TNC) and oxychlordane (OCD), a major metabolite of the insecticide chlordane, increases the

METHODS

A total of 304 histologically confirmed, incident primary breast-cancer patients and 186 histologically confirmed incident benign breast-disease controls were included in the study between 1994 and 1997. Breast adipose tissue not needed for diagnostic purposes was collected and analysed for TNC, OCD and other organochlorine compounds. A standardised, structured questionnaire was used to obtain information on major known, or suspected, risk factors for breast cancer.

RESULTS

The age and lipid-adjusted geometric mean adipose-tissue levels of OCD were similar between the cases [36.4 p.p.b., 95% confidence interval (CI) 34.7-38.2 p.p.b.] and controls (38.0 p.p.b., 95% Cl 35.7-40.6 p.p.b.). The age and lipid-adjusted geometric mean adipose-tissue levels of TNC between the cases (55.5 p.p.b., 95% CI 52.6-58.5 p.p.b.) and controls (58.1 p.p.b., 95% CI 54.2-62.3 p.p.b.) were also similar. There was no association between breast-cancer risk and mean adipose-tissue levels of OCD and TNC. The covariate-adjusted odds ratio (OR) was 0.7 (95% CI 0.4-1.3) for OCD and 1.1 (95% CI 0.6-1.9) for TNC, when the highest quartile was compared with the lowest. The risk also did not vary based on oestrogen or progesterone receptor status or menopausal status.

DISCUSSION

We found no significantly increased risk of breast cancer associated with breast adipose-tissue levels of OCD or TNC; this is consistent with recent epidemiological studies, indicating that environmental exposure to organochlorine compounds does not have an overall significant impact on breast-cancer risk.

Joint effects of nine polychlorinated biphenyl (PCB) congeners on breast cancer risk

BACKGROUND

Polychlorinated biphenyls (PCB) have been a major environmental health concern because of their wide distribution and persistence in the environment. Estimating joint effects of all congeners in a single analysis is complicated by correlation among exposure levels, and the resulting collinearity makes the results difficult to interpret.

METHODS

Patients with breast-related surgery at Yale-New Haven Hospital were interviewed using a standardized questionnaire, and breast adipose tissue samples were analysed for nine PCB congeners (74, 118, 138, 153, 156, 170, 180, 183, 187). The study recruited 490 women (304 cases and 186 controls) between 1994 and 1997. Logistic ridge regression was used to analyse the instability caused by collinearity.

RESULTS

Although total PCB did not appear to be associated with breast cancer risk, significant differences in effect were observed among the nine congeners. Logistic ridge regression demonstrated a protective effect on breast cancer risk for a potentially anti-oestrogenic and dioxin-like congener, 156, while two phenobarbital, CYP1A and CYP2B inducers had an adverse effect, 180 and 183. This analysis also suggested that a protective effect for another phenobarbital congener, 153, was largely explained by instability caused by collinearity.

CONCLUSIONS

These results indicate that studies of PCB congeners and health require an in-depth statistical analysis in order to better understand the complex issues related to their collinearity.

Food group intake and the risk of oral epithelial dysplasia in a United States population

OBJECTIVES

Oral epithelial dysplasia (OED) is a histopathologic diagnosis associated with an increased risk of oral cancer. The paper explores the relationship between OED risk and food group intake.

METHODS

In this case-control study, incident cases of OED were identified through two oral pathology laboratories. Controls, pair-matched 1:1 to cases on age (+/- 5 years), gender, appointment date (+/- 1 year), and surgeon, were identified through the office in which the respective case was biopsied. Exposure data were obtained via a telephone interview and mailed food-frequency questionnaire. Conditional logistic regression was used to obtain odds ratio point estimates.

RESULTS

Based upon 87 matched pairs and after controlling for smoking, drinking, and other potential covariates there was an apparent inverse relationship between OED risk and the consumption of fruits and vegetables, with the intake of these foods being associated with a strong attenuating effect among smokers. OED risk decreased with increased poultry consumption, but increased modestly with bread/cereal and dairy food intake.

CONCLUSIONS

This investigation provides evidence that some aspects of diet may be associated with the risk of OED. It also suggests that in oral carcinogenesis the role of diet is not simply one of a late effect.

A randomized controlled trial of auricular acupuncture for cocaine dependence

BACKGROUND

Partly because of a lack of a conventional, effective treatment for cocaine addiction, auricular acupuncture is used to treat this disorder in numerous drug treatment facilities across the country for both primary cocaine-dependent and opiate-dependent populations.

OBJECTIVE

To evaluate the effectiveness of auricular acupuncture for the treatment of cocaine addiction.

METHODS

Eighty-two cocaine-dependent, methadone-maintained patients were randomly assigned to 1 of 3 conditions: auricular acupuncture, a needle-insertion control condition, or a no-needle relaxation control. Treatment sessions were provided 5 times weekly for 8 weeks. The primary outcome was cocaine use assessed by 3-times-weekly urine toxicology screens.

RESULTS

Longitudinal analysis of the urine data for the intent-to-treat sample showed that patients assigned to acupuncture were significantly more likely to provide cocaine-negative urine samples relative to both the relaxation control (odds ratio, 3.41; 95% confidence interval, 1.33-8.72; P =. 01) and the needle-insertion control (odds ratio, 2.40; 95% confidence interval, 1.00-5.75; P =.05).

CONCLUSIONS

Findings from the current study suggest that acupuncture shows promise for the treatment of cocaine dependence. Further investigation of this treatment modality appears to be warranted.

Breast cancer risk associated with congeners of polychlorinated biphenyls

Experimental studies show that hormonal and nonhormonal activities of polychlorinated biphenyls (PCBs) are structure dependent, suggesting that the breast cancer risk associated with PCBs may vary according to specific PCB congeners. In 1994-1997, the authors conducted a case-control study of Connecticut women to investigate whether breast cancer risk is associated with body burden of PCBs and varies by PCB congeners. A total of 304 breast cancer cases and 186 controls aged 40-79 years were recruited into the study. Fresh breast adipose tissue was analyzed for PCBs. The age- and lipid-adjusted geometric mean tissue levels of total PCBs were not significantly different (p = 0.46) for the cases (478.6 parts per billion) and controls (494.1 parts per billion). The covariate-adjusted odds ratio was 0.7 (95% confidence interval: 0.4, 1.1) for all study participants when the third tertile was compared with the lowest tertile. No individual congeners or groups of congeners were associated with a significantly increased risk of breast cancer. Further stratification by type of breast disease; menopausal, parity, and lactation status; and body size also showed no significant association with body levels of PCBs. These results suggest that environmental exposure to PCBs may not substantially affect breast cancer risk.

Pulse pressure and risk for myocardial infarction and heart failure in the elderly

OBJECTIVES

We sought to determine whether pulse pressure (PP), a measure of arterial stiffness, is an independent predictor of the incidence of coronary heart disease (CHD), congestive heart failure (CHF) and overall mortality among community-dwelling elderly.

BACKGROUND

Current hypertension guidelines classify cardiovascular risk on the basis of elevated systolic blood pressure (SBP) or diastolic blood pressure (DBP) without considering their combined effects. Recent studies suggest that PP is a strong predictor of cardiovascular end points, but few data are available among community elderly.

METHODS

The study sample included 2,152 individuals age > or =65 years, who were participants in the Established Populations for Epidemiologic Study of the Elderly program, free of CHD and CHF at baseline and still alive at one year after enrollment. Blood pressure was measured at baseline. Incidence of CHD, incidence of CHF and total mortality were monitored in the following 10 years.

RESULTS

There were 328 incident CHD events, 224 incident CHF events and 1,046 persons who died of any cause. Pulse pressure showed a strong and linear relationship with each end point. After adjusting for demographics, comorbidity and CHD risk factors, a 10-mm Hg increment in PP was associated with a 12% increase in CHD risk (95% confidence interval [CI], 2% to 22%), a 14% increase in CHF risk (95% CI, 5% to 24%), and a 6% increase in overall mortality (95% CI, 0% to 12%). While SBP and mean arterial pressure (MAP) also showed positive associations with the end points, PP yielded the highest likelihood ratio chi-square. When PP was entered in the model in conjunction with other blood pressure parameters (SBP, DBP, MAP or hypertension stage, respectively), the association remained positive for PP but became negative for the other blood pressure variables. The effect of PP persisted after adjusting for current medication use and was present in normotensive individuals and individuals with isolated systolic hypertension but not in individuals with diastolic hypertension.

CONCLUSIONS

Elevated PP is a powerful independent predictor of cardiovascular end points in the elderly.

Exposure to electromagnetic fields from use of electric blankets and other in-home electrical appliances and breast cancer risk

Exposure to electromagnetic fields (EMFs) from use of electric blankets and other in-home electrical appliances has been hypothesized to increase breast cancer risk. To test the hypothesis, the authors analyzed data from a case-control study of female breast cancer conducted in Connecticut in 1994-1997. A total of 608 incident breast cancer patients and 609 age frequency-matched controls, 31-85 years old, were interviewed by trained study interviewers using a standardized, structured questionnaire to obtain information on lifetime use of various in-home electrical appliances. A total of 40% of the cases and 43% of the controls reported regular use of electric blankets in their lifetime, which gave an adjusted odds ratio of 0.9 (95% confidence interval (CI): 0.7, 1.1). For those who reported using electric blankets continuously throughout the night, the adjusted odds ratio was 0.9 (95% CI: 0.7, 1.2) when compared with never users. The risk did not vary according to age at first use, duration of use, or menopausal and estrogen receptor status. The authors also did not find an association between use of other major in-home electrical appliances and breast cancer risk. In conclusion, exposure to EMFs from in-home electrical appliance use was not found to increase breast cancer risk in this study.

Clinical measurement, statistical analysis, and risk-benefit: controversies from trials of spinal injury

BACKGROUND

The National Acute Spinal Cord Injury Studies have been a series of trials assessing the role of pharmacologic agents in the prevention of secondary neuronal damage after acute spinal cord injury.

METHODS

The trials were multicenter randomized, controlled studies.

RESULTS

Two trials have demonstrated the efficacy of high-dose methylprednisolone in improving neurologic and functional recovery and have shown a reassuring safety profile.

CONCLUSION

This study responds to a recent commentary on these trials and examines in particular the roles of clinical measurement, statistical analysis, and risk benefit in assembling evidence for or against innovative therapies.

Risk of female breast cancer associated with serum polychlorinated biphenyls and 1,1-dichloro-2,2'-bis(p-chlorophenyl)ethylene

This case-control study was designed to investigate the relationship between polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2'-bis(p-chlorophenyl)ethylene (DDE) and breast cancer risk in Connecticut. Cases were incident breast cancer patients who were either residents of Tolland County or who had a breast-related surgery at the Yale-New Haven Hospital in New Haven County. Controls were randomly selected from Tolland County residents or from patients who had newly diagnosed benign breast diseases or normal tissue at Yale-New Haven Hospital. A total of 475 cases and 502 controls had their serum samples analyzed for PCBs and DDE in 1995-1997. The age- and lipid-adjusted geometric mean serum level of DDE was comparable between the cases (460.1 ppb) and controls (456.2 ppb). The geometric mean serum level of PCBs was also comparable between cases (733.1 ppb) and controls (747.6 ppb). After adjustment for confounding factors, odds ratios of 0.96 (95% confidence interval, 0.67-1.36) for DDE and 0.95 (95% confidence interval, 0.68-1.32) for PCBs were observed when the third tertile was compared with the lowest. Further stratification by parity, lactation, and menopausal and estrogen receptor status also showed no significant association with serum levels of DDE or PCBs. The results by PCB congener groups also showed no major increased risk associated with any of the congener groups. Our study does not support the hypothesis that DDE and PCBs, as encountered through environmental exposure, increase the risk of female breast cancer.