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K L Koenig

Publications and source records attributed to K L Koenig.

At least 19 recordsLinked to original sources
PubMed2000

Diet, smoking and anthropometric indices and postmenopausal bone fractures: a prospective study.

OBJECTIVE: Bone fractures are an important cause of morbidity and mortality among the elderly in the US. The present study assesses the possible role of a number of risk factors for postmenopausal bone fractures. METHODS: We analysed the relationships of anthropometric, demographic and lifestyle factors with the risk of bone fracture among 6250 postmenopausal women in a prospective cohort study, the New York University Women's Health Study. RESULTS: After an average of 7.6 years of follow-up, 1025 new incident bone fractures were reported, including 34 hip and 159 wrist fractures (incidence rates; 71.6 and 334.7 per 105 woman-years, respectively). The risk of fracture increased with increasing age, body height and total fat intake, while it was significantly lower among obese and African American women. The relative risk among African Americans was 0.45 (95% CI: 0.32-0.63) compared with non-African Americans. Women taller than 170 cm had a 64% increase in risk of fractures, as compared with those under 155 cm. These associations were generally more pronounced when fractures were limited to those at the hip and wrist. CONCLUSIONS: The present study provides an indication for a potential role of dietary fat in the development of postmenopausal fractures and further evidence to support protective effects of obesity, short stature and African American ethnicity.

Adult↗
PubMed2000

Out-of-hospital intravenous cannulation: the perspective of patients treated by London Ambulance Service paramedics.

OBJECTIVES: Previous research has highlighted concern about infection rates in field-placed intravenous (IV) cannulae. In a study of IV placement by London Ambulance Service (LAS) paramedics, 17% of placements were judged to be inappropriate. Large variations in rates of IV placement between LAS paramedics were found. The authors' hypothesis was that placement of an IV carries disadvantages-pain, discomfort, distress, and infection-which may be unacceptable to patients. METHODS: This was a survey of all patients having an IV placed by LAS paramedics and transported to one of three London emergency departments (EDs) over a three-week period in December 1996. Patients were excluded if they had a self-inflicted injury/illness, were less than 14 years old, had no known address, or were visitors to the UK, or if their family doctor suggested it was not appropriate to contact the patient. Pain, discomfort, and distress; infection; satisfaction; understanding of the reason for cannulation; and out-of-hospital cannula use were all ascertained and analyzed with chi-square analysis. RESULTS: Thirty-nine percent of the respondents experienced some discomfort, 39% some pain, and 17% some distress. No patient reported an infection. Distress was more likely to be reported if there was no understanding of why the IV cannula was placed (chi2 [1] 6.1; p < 0.05). Further unstructured information revealed satisfaction with the IV cannulation and with general care. CONCLUSIONS: Despite the disadvantages of IV placement being reported by some respondents, overall levels of satisfaction were high, suggesting that these disadvantages were not unacceptable to patients. However, in the context of the 24,000 patients cannulated each year by LAS paramedics, "costs" to the patient are considerable.

Adolescent↗
PubMed1999

Comparison of active and cancer registry-based follow-up for breast cancer in a prospective cohort study.

The authors compared the relative effectiveness of two distinct follow-up designs in prospective cohort studies--the active approach, based on direct contact with study subjects, and the passive approach, based on record linkages with population-based cancer registries--utilizing available information from the New York University Women's Health Study (WHS) and the New York State Cancer Registry (NYSCR). The analyses were limited to breast cancer cases identified during the period 1985-1992, for which follow-up was considered reasonably complete by both the WHS and the NYSCR. Among 12,947 cohort members who reported a New York State address, 303 pathologically confirmed cases were identified through active follow-up and 284 through record linkage. Sixty-three percent of cancers were identified by both sources, 21% by the WHS only, and 16% by the NYSCR only. The agreement was appreciably better for invasive cancers. The percentage of cases identified only by the NYSCR was increased among subjects whose active follow-up was incomplete, as well as among nonwhites, obese patients, and parous patients. This suggests that relying on either type of follow-up alone may introduce certain biases in evaluating risk factors for breast cancer. Combining both approaches appears to be a better strategy in prospective cohort studies.

Adult↗
PubMed1999

Epidemiologic correlates with menstrual cycle length in middle aged women.

While irregular menstruations have been associated with lower cumulative exposure to the ovarian steroids, shorter regular cycles have been postulated to increase the cumulative exposure. Epidemiological correlates with menstrual patterns were analyzed among 4900 premenopausal women aged 45 or younger from the New York University Women's Health Study. The length of regular menstrual cycles increased with increasing age at menarche, body mass index and parity, but decreased with age, nonwhite racial background and current smoking. The likelihood of irregular cycles increased with increasing age, body mass index and number of cigarettes smoked per day. With adjustment for age, body mass index and number of cigarettes smoked per day, the risk of irregular cycles was marginally positively associated with total fat intake.

Adult↗
PubMed1999

Body fat distribution and obesity in pre- and postmenopausal breast cancer.

BACKGROUND: Excessive body weight is known to increase the risk of postmenopausal, but not premenopausal breast cancer. Some studies have suggested that being overweight is protective against premenopausal breast cancer, but the evidence is not compelling. Much less is known about the role of body fat distribution in either pre- or postmenopausal breast cancer. METHODS: Breast cancer risk was examined in relation to body weight, height, Quetelet index (kg/m2), and waist/hip ratio (WHR) in the New York University Women's Health Study, a prospective cohort study. Cases were 109 premenopausal and 150 postmenopausal women diagnosed with breast cancer between 1985 and 1994. Non-cases were 8,157 cohort members free of breast cancer. RESULTS: Among premenopausal women, there was an increasing risk of breast cancer with increasing WHR. The relative risk (RR) of breast cancer increased to 1.72 (95% confidence interval [CI]: 1.0-3.1) in the upper quartile of WHR. The association was limited to subjects who had elevated Quetelet index, but not among those with lower weight. Overall, Quetelet index itself was not related to breast cancer risk in the premenopausal group, but there was a protective association among those ranking below the median WHR. In postmenopausal women, the RR for breast cancer increased to 2.36 (95% CI: 1.4-3.9) in the upper quartile of Quetelet index, but there was no association with WHR. Height was not associated with breast cancer in this study. CONCLUSIONS: The study confirms that excessive body weight increases breast cancer risk in postmenopausal women. On the contrary, in premenopausal women, excessive body weight may be protective among women who have a lower-body type of fat accumulation (low WHR). An upper-body fat accumulation (high WHR) is a predictor of breast cancer risk in premenopausal women, and this effect is especially pronounced among subjects who are overweight.

Adipose Tissue↗
PubMed1998

Prospective study of factors influencing the onset of natural menopause.

Late or early menopause has been implicated in risk of several chronic diseases in women. To study factors influencing the onset of natural menopause, the authors analyzed the follow-up data of 4694 premenopausal women who enrolled in the New York University Women Study at ages 34-61. In an average of 5.4 years of observation, there were 2035 incidences of menopause, with the median age of 51.3 years. Current smokers experienced menopause 0.75 years earlier than never-smokers. Those who smoked more than 10 cigarettes per day had a 40% increase in risk of earlier menopause. In contrast, women who had three or more children experienced menopause 0.86 years later than nulliparous women, and Jewish women, 0.66 years later than Catholic women. There was also a modest increase in the age at menopause with increasing body mass index. This prospective study provides solid epidemiologic evidence that several factors other than cigarette smoking have impact on the onset of natural menopause.

Adult↗
PubMed1997

Relation of serum levels of testosterone and dehydroepiandrosterone sulfate to risk of breast cancer in postmenopausal women.

The authors examined the relation between postmenopausal serum levels of testosterone and dehydroepiandrosterone sulfate (DHEAS) and subsequent risk of breast cancer in a case-control study nested within the New York University Women's Health Study cohort. A specific objective of their analysis was to examine whether androgens had an effect on breast cancer risk independent of their effect on the biologic availability of estrogen. A total of 130 cases of breast cancer were diagnosed prior to 1991 in a cohort of 7,054 postmenopausal women who had donated blood and completed questionnaires at a breast cancer screening clinic in New York City between 1985 and 1991. For each case, two controls were selected, matching the case on age at blood donation and length of storage of serum specimens. Biochemical analyses were performed on sera that had been stored at -80 degrees C since sampling. The present report includes a subset of 85 matched sets, for whom at least 6 months had elapsed between blood donation and diagnosis of the case. In univariate analysis, testosterone was positively associated with breast cancer risk (odds ratio (OR) for the highest quartile = 2.7, 95% confidence interval (CI) 1.1-6.8, p < 0.05, test for trend). However, after including % estradiol bound to sex hormone-binding globulin (SHBG) and total estradiol in the statistical model, the odds ratios associated with higher levels of testosterone were considerably reduced, and there was no longer a significant trend (OR for the highest quartile = 1.2, 95% CI 0.4-3.5). Conversely, breast cancer risk remained positively associated with total estradiol levels (OR for the highest quartile = 2.9, 95% CI 1.0-8.3) and negatively associated with % estradiol bound to SHBG (OR for the highest quartile = 0.05, 95% CI 0.01-0.19) after adjustment for serum testosterone levels. These results are consistent with the hypothesis that testosterone has an indirect effect on breast cancer risk, via its influence on the amount of bioavailable estrogen. No evidence was found of an association between DHEAS and risk of breast cancer in postmenopausal women.

Adult↗
PubMed1996

Chromatic and luminance systems deficits in glaucoma.

The purpose of this study was to compare the effects of glaucoma, at different stages of the disease process, on the two color-opponent system and on the luminance system. Discrimination thresholds were measured along the two equiluminant cardinal color axes (RG and YV) and along an achromatic luminance axis (LD) in 27 patients with open-angle glaucoma (OAG) and in 13 glaucoma suspects. Patients with OAG showed increased thresholds along all three axes. The threshold increases correlated significantly with the level of visual field loss. For glaucoma suspects, thresholds were also increased along all three axes. A subgroup of patients with OAG, those with pigmentary glaucoma, showed minimal increases in threshold along the RG axis. To further investigate this finding an additional 15 patients, seven with primary OAG and eight with pigmentary glaucoma were run in a two-alternative forced-choice experiment. For patients with pigmentary glaucoma, thresholds were increased less along the RG axis. The results of the study for OAG patients and glaucoma suspects are consistent with deficits in the two color-opponent systems, and in the luminance system.

Adult↗
PubMed1996

Disaster nomenclature--a functional impact approach: the PICE system.

A standard nomenclature that concisely describes any disaster is currently lacking. This article describes a model taxonomy system. Instead of the term "disaster," a root word "PICE," "potential injury-creating event," is used. Descriptive modifiers to account for all possible scenarios surround this root word, as illustrated. [table: see text] A modifier is chosen from each column and a stage is assigned to each PICE. Column A describes the potential for additional casualties. Column B describes whether resources are overwhelmed and, if so, whether they must simply be augmented (disruptive) or they must first be reconstituted (paralytic). Column C describes the extent of geographic involvement. "Stage" refers strictly to the likelihood that outside medical assistance will be needed. Stage 0 means there is little chance, stage I means there is a small chance (place outside help on "alert"), stage II means there is a moderate chance (place on "standby"), and stage III means local medical resources are clearly overwhelmed (immediately dispatch outside resources, commit personnel, prepare remote hospitals). For example, a multiple vehicle crash in a large city would be a "static, controlled, local PICE, stage 0." In conclusion, a new nomenclature for describing disasters is reported. A short phrase describes the incident and communicates the need for outside assistance. The model may be useful for disaster planning, management, and research.

Disasters↗
PubMed1995

Estimating the reliability of an exposure variable in the presence of confounders.

In this paper we discuss estimation of the reliability of an exposure variable in the presence of confounders measured without error. We give an explicit formula that shows how the exposure becomes less reliable as the degree of correlation between the exposure and confounders increases. We also discuss biases in the corresponding logistic regression estimates and methods for correction. Data from a matched case-control study of hormone levels and risk of breast cancer are used to illustrate the methods.

Breast Neoplasms↗
PubMed1995

A prospective study of endogenous estrogens and breast cancer in postmenopausal women.

BACKGROUND: Circumstantial evidence links endogenous estrogens to increased risk of breast cancer in women, but direct epidemiologic support is limited. In particular, only a few small prospective studies have addressed this issue. PURPOSE: Our purpose was to assess breast cancer risk in relation to circulating levels of the two major endogenous estrogens, estrone and estradiol, measured before the clinical onset of the disease. METHODS: The association between serum levels of estrogens and the risk of breast cancer was examined in a prospective cohort study of 14,291 New York City women, 35-65 years of age, who received screening for breast cancer at the time of blood sampling and who had not been diagnosed with breast cancer. During the first 5 1/2 years of study, we identified 130 breast cancers among the postmenopausal group (7063 women, 35,509 person-years). The case subjects and twice as many postmenopausal control subjects were included in a case-control study nested within the cohort. Biochemical analyses for percent free estradiol, percent estradiol bound to sex hormone-binding globulin (SHBG), total estradiol, estrone, and follicle-stimulating hormone were performed on sera that had been kept at -80 degrees C since sampling. RESULTS: For increasing quartiles of total estradiol, the odds ratio (ORs) of breast cancer, as adjusted for Quetelet index (weight in kilograms divided by the square of the height in meters), were 1.0, 0.9, 1.8, and 1.8 (P value for trend = .06); the ORs for increasing quartiles of estrone were 1.0, 2.2, 3.7, and 2.5 (P value for trend = .06). For increasing quartiles of free estradiol, defined as the fraction of estradiol that is not bound to proteins, the Quetelet index-adjusted ORs of breast cancer were 1.0, 1.4, 3.0, and 2.9 (P value for trend < .01). When we considered the percent of estradiol bound to SHBG, the Quetelet index-adjusted ORs were 1.0, 0.70, 0.40, and 0.32 (P value for trend < .01), thus suggesting a strong protective effect. These associations persisted or became even stronger when analyses were restricted to women whose samples had been drawn 2 or more years before breast cancer diagnosis. CONCLUSIONS: These data represent the first confirmation in a large prospective epidemiologic study of a link between circulating estrogens and breast cancer risk. Although estrogen levels appeared to fall within the conventional limits of normality in all women under study, those who subsequently developed breast cancer tended to show higher levels of estrone, total estradiol, and free estradiol, and a lower percent of estradiol bound to SHBG than women who remained free of cancer. IMPLICATIONS: Factors that increase endogenous estrogen production or reduce the binding of estradiol to SHBG may increase a woman's risk of developing breast cancer later in life.

Breast Neoplasms↗