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Infestation of European corn borer (Lepidoptera: Crambidae) in sweet corn as predicted by time of oviposition.

Oviposition by European corn borer, Ostrinia nubilalis Hübn, was examined in relation to sweet corn development from 1994 to 1996, and related to harvest infestation levels. Stepwise multiple regression and linear regression showed that 79-87% of the variability of larvae per ear or proportion of ears infested at harvest was explained by the number of egg masses laid from about anthesis to brown silk stages. The analyses indicated three periods of oviposition with differing implications to harvest infestation level: (1) eggs laid from 784-337 degree-days (DD) before harvest (before green tassel) had very low correlation to harvest infestation; (2) eggs laid from 336-169 DD before harvest (green tassel to green silk) were highly correlated with harvest infestation; and (3) eggs laid during the last 168 DD of sweet corn development (green silk to harvest) had low to moderate correlation with harvest infestation. The 336-169 DD period corresponded to the anthesis to brown silk growth stages, which was approximately 14-21 d long, and would be the likely period for optimum chemical control. The results of this study are compared with existing recommendations from the midwestern and northeastern U.S., and potential explanations for the patterns observed are discussed.

Animals↗

Risks and costs of end-stage renal disease after heart transplantation.

OBJECTIVES: To estimate the risks and costs of end-stage renal disease (ESRD) after heart transplantation. BACKGROUND: Previous studies have shown high rates of ESRD among solid-organ transplant patients, but the relevance of these studies for current transplant practices and policies is unclear. Limitations of prior studies include relatively small, single-center samples and estimates made before implementing suggested practice changes to reduce ESRD risk. METHODS: Medicare beneficiaries who underwent heart transplantation between 1989 and 1994 were eligible for study inclusion (n=2088). Thirty-four patients undergoing dialysis or who had the diagnosis of ESRD before or at transplantation were excluded from the study. ESRD was defined as any patient undergoing renal transplantation or requiring dialysis for more than 3 months. Mortality and ESRD events were recorded up to 1995. ESRD risk was estimated using the Kaplan-Meier product-limit estimator and logistic regression analyses. Linear regression was performed to determine expenditures for treating ESRD, and we developed long-term models of the risk and direct medical costs of ESRD care. RESULTS: The annual risk of ESRD was 0.37% in the first year after transplant and increased to 4.49% by the sixth posttransplant year. There was no significant trend in the risk of ESRD based on the year of transplantation, even after adjusting for patient characteristics. The average cumulative 10-year direct cost of ESRD per patient undergoing heart transplantation exceeded $13,000. CONCLUSIONS: In a large, national sample of patients undergoing heart transplantation, ESRD is not rare, even for patients undergoing transplant after the development of new practices intended to reduce its occurrence. ESRD remains an important component of the costs of heart transplantation.

Adult↗

The association between persistent occiput posterior position and neonatal outcomes.

OBJECTIVE: To examine the effect of persistent occiput posterior position on neonatal outcome. METHODS: This is a retrospective cohort study of 31,392 term, cephalic, singleton births. Women with neonates born in persistent occiput posterior position at delivery were compared to those with occiput anterior position. Women with occiput transverse position were excluded. The association between occiput posterior position and neonatal outcomes, including 5-minute Apgar scores, umbilical cord gases, meconium-stained amniotic fluid, meconium aspiration syndrome, birth trauma, admission to the intensive care nursery, and length of stay were examined using chi(2) and Student t tests. Potential confounders (maternal age, ethnicity, parity, gestational age, epidural anesthesia, labor induction, length of labor, meconium, chorioamnionitis, birth weight, and year of delivery) were controlled for by using multivariable logistic regression and linear regression analyses. RESULTS: There were 2,591 (8.2%) neonates delivered in occiput posterior position of the total cohort of 31,392 deliveries. Compared with occiput anterior, neonates delivered in occiput posterior position had higher risks for adverse outcomes, including 5-minute Apgar score less than 7 (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.17-1.91), acidemic umbilical cord gases (OR 2.05, 95% CI 1.52-2.77), meconium-stained amniotic fluid (OR 1.29, 95% CI 1.17-1.42), birth trauma (OR 1.77, 95% CI 1.22-2.57), admission to the intensive care nursery (OR 1.57, 95% CI 1.28-1.92), and longer neonatal stay in the hospital (OR 2.69, 95% CI 2.22-3.25). CONCLUSION: Persistent occiput posterior position at delivery is associated with higher risks of adverse neonatal outcomes compared with neonates delivered in the occiput anterior position. This information may be important in counseling women who experience persistent occiput posterior position in labor. LEVEL OF EVIDENCE: II-2.

Adult↗

Future orientation and suicide ideation and attempts in depressed adults ages 50 and over.

OBJECTIVE: The objective of this study was to test the hypothesis that future orientation is associated with lower levels of suicide ideation and lower likelihood of suicide attempt in a sample of patients in treatment for major depression. METHODS: Two hundred two participants (116 female, 57%) ages 50-88 years were recruited from inpatient and outpatient settings. All were diagnosed with major depression using a structured diagnostic interview. Suicide ideation was assessed with the Scale for Suicide Ideation (both current and worst point ratings), and a measure of future orientation was created to assess future expectancies. The authors predicted that greater future orientation would be associated with less current and worst point suicide ideation, and would distinguish current and lifetime suicide attempters from nonattempters. Hypotheses were tested using multivariate logistic regression and linear regression analyses that accounted for age, gender, hopelessness, and depression. RESULTS: As hypothesized, higher future orientation scores were associated with lower current suicidal ideation, less intense suicidal ideation at its worst point, and lower probability of a history of attempted suicide after accounting for covariates. Future orientation was not associated with current attempt status. CONCLUSIONS: Future orientation holds promise as a cognitive variable associated with decreased suicide risk; a better understanding of its putative protective role is needed. Treatments designed to enhance future orientation might decrease suicide risk.

Aged↗

Blood flow, temperature, and heat loss of skin exposed to local radiative and convective cooling.

The relationship between skin blood flow (SBF) and temperature was evaluated and the heat loss calculated for locally applied thermal stimuli. In 10 subjects the palm was exposed to room climate, pure convective air currents, and pure radiation, which resulted in skin temperatures between 23 and 36 degrees C. Skin blood flow was estimated by laser Doppler flowmetry and local skin temperature was measured by a thermistor probe. Linear regression of SBF on skin temperature revealed significant correlations (r = 0.87, p less than 0.05) within subjects and large variations in estimated slopes (s/m = 34%) between subjects. Therefore, SBF was normalized to the room climate value in each separate experiment. When skin temperature and normalized SBF from all subjects were included in the regression analysis, a nearly linear relationship was confirmed (r = 0.88, p less than 0.0005). Radiative cooling (17 degrees C) doubled the heat loss, reduced skin temperature by 3.7 degrees C, and left SBF virtually unchanged compared with room climate values. When convective cooling (19 degrees C) was applied at 2 air current velocities (0.5 and 1.0 ms-1), palm blood flow diminished to 60 and 53%, respectively, of room climate values. Corresponding heat losses with convective cooling decreased to 68 and 70%, respectively, of room climate values. Linear regression of local heat loss on normalized SBF gave a significant correlation coefficient of 0.79 (p less than 0.001).

Adolescent↗

Correlation between computer-assisted femoral arteriography and physiological tests in hypercholesterolaemic patients: a methodological study with special reference to clinical trials.

The validity of computer-assisted femoral arteriography, for the study of regression/progression of atherosclerosis in follow-up clinical trials, was investigated by comparison with routine physiological estimates of peripheral circulatory function. Thus, in 114 hypercholesterolaemic patients, the results of aorto-femoral arteriography were compared with those of leg segmental blood pressure measurement, oscillometry, digital pulse plethysmography, and bicycle and treadmill exercise tests. In 107 patients, 18 with symptoms of peripheral vascular disease (PVD) and 89 asymptomatic, magnification arteriograms of a 20 cm segment of the right or left superficial femoral artery were obtained. These arteriograms were digitized and the following variables were calculated: arterial lumen volume (corrected for body size), per cent stenosis, and edge roughness. The correlation between arteriographic and physiological variables was investigated with a linear regression model, taking into account the possible interaction with sex, and presence or absence of symptoms of PVD. Lumen volume correlated significantly with all five physiological variables, and per cent stenosis correlated significantly with four of the physiological variables. For the roughness measure, however a significant correlation was found only with plethysmography. By using logistic multiple regression analysis linear functions of physiological variables were constructed to detect ilio-femoral arterial occlusion. The sensitivity/specificity for detection of right-sided, left-sided, and bilateral occlusion was 0.83/0.98, 0.78/0.98, and 0.60/1.00 respectively (N = 108-111). Systolic blood pressure (ankle-arm ratio) was the single variable most closely correlated to the likelihood of arterial occlusions. It is concluded that arterial lumen volume and per cent stenosis, measured for the digitized femoral arteriogram, correlate well with physiological variables, which reflect the state of atherosclerosis both in the femoral arteries and in other arterial beds including the heart, and that routine physiological tests can be used to identify patients with arterial occlusions in the iliac and femoral arteries.

Adult↗

Tests of stepping as indicators of mobility, balance, and fall risk in balance-impaired older adults.

OBJECTIVES: To determine the relationships between two tests of stepping ability (the maximal step length (MSL) and rapid step test (RST)) and standard tests of standing balance, gait, mobility, and functional impairment in a group of at-risk older adults. DESIGN: Cross-sectional study. SETTING: University-based laboratory. PARTICIPANTS: One hundred sixty-seven mildly balance-impaired older adults recruited for a balance-training and fall-reduction program (mean age 78, range 65-90). MEASUREMENTS: Measures of stepping maximally (MSL, the ability to maximally step out and return to the initial position) and rapidly (RST, the time taken to step out and return in multiple directions as fast as possible); standard measures of balance, gait, and mobility including timed tandem stance (TS), tandem walk (TW, both timing and errors), timed unipedal stance (US), timed up and go (TUG), performance oriented mobility assessment (POMA), and 6-minute walk (SMW); measures of leg strength (peak knee and ankle torque and power at slow and fast speeds); self-report measures of frequent falls (>2 per 12 months), disability (Established Population for Epidemiologic Studies of the Elderly (EPESE) physical function), and confidence to avoid falls (Activity-specific Balance Confidence (ABC) Scale). Spearman and Pearson correlation, intraclass correlation coefficient, logistic regression, and linear regression were used for data analysis. RESULTS: MSL consistently predicted a number of self-report and performance measures at least as well as other standard balance measures. MSL correlations with EPESE physical function, ABC, TUG, and POMA scores; SMW; and peak maximum knee and ankle torque and power were at least as high as those correlations seen with TS, TW, or US. MSL score was associated with the risk of being a frequent faller. In addition, the six MSL directions were highly correlated (up to 0.96), and any one of the leg directions yielded similar relationships with functional measures and a history of falls. Relationships between RST and these measures were relatively modest. CONCLUSION: MSL is as good a predictor of mobility performance, frequent falls, self-reported function, and balance confidence as standard stance tests such as US. MSL simplified to one direction may be a useful clinical indicator of mobility, balance, and fall risk in older adults.

Accidental Falls↗

Dietary intake of antioxidant (pro)-vitamins, respiratory symptoms and pulmonary function: the MORGEN study.

BACKGROUND: A study was undertaken to investigate the relationships between the intake of the antioxidant (pro)-vitamins C, E and beta-carotene and the presence of respiratory symptoms and lung function. METHODS: Complete data were collected in a cross sectional study in a random sample of the Dutch population on 6555 adults during 1994 and 1995. Antioxidant intake was assessed by a semi-quantitative food frequency questionnaire and respiratory symptoms (cough, phlegm, productive cough, wheeze, shortness of breath) were assessed by a self-administered questionnaire. Prevalence odds ratios for symptoms were calculated using logistic regression analysis. Linear regression analysis was used for forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). The results are presented as a comparison between the 90th and 10th percentiles of antioxidant intake. RESULTS: Vitamin C intake was not associated with most symptoms but was inversely related with cough. Subjects with a high intake of vitamin C had a 53 ml (95% CI 23 to 83) higher FEV1 and 79 ml (95% CI 42 to 116) higher FVC than those with a low vitamin C intake. Vitamin E intake showed no association with most symptoms and lung function, but had a positive association with productive cough. The intake of beta-carotene was not associated with most symptoms but had a positive association with wheeze. However, subjects with a high intake of beta-carotene had a 60 ml (95% CI 31 to 89) higher FEV1 and 75 ml (95% CI 40 to 110) higher FVC than those with a low intake of beta-carotene. CONCLUSIONS: The results of this study suggest that a high intake of vitamin C or beta-carotene is protective for FEV1 and FVC compared with a low intake, but not for respiratory symptoms.

Adult↗

Factors associated with length of stay in hospital for suspected community-acquired pneumonia.

OBJECTIVE: To determine factors associated with the length of stay (LOS) for patients with suspected community-acquired pneumonia (CAP) who required hospitalization for treatment. STUDY DESIGN: The authors studied a population-based prospective cohort of 2,757 adults with suspected CAP who were admitted over a two-year period. Logistic regression, multiple linear regression, and classification and regression trees were used to determine the factors associated with LOS. SETTING: The study was conducted in two community and tertiary care hospitals, two community and secondary care hospitals, and two community hospitals in the Capital Health Region of Edmonton, Alberta. RESULTS: Symptoms such as sweats, shaking chills and wheezing were associated with an LOS of seven days or shorter, whereas weight loss, functional impairment, heart, renal or neoplastic diseases and time to first dose of antibiotic were predictive of an LOS greater than seven days. Regression tree analysis indicated that rapid achievement of physiological stability was associated with a shorter LOS. The use of an indwelling urinary catheter was found to be an important determinant of LOS. CONCLUSIONS: The present study found several new associations with increased LOS in patients with CAP, including functional status, time to receipt of first dose of antibiotic therapy, use of certain antibiotics, presence of a urinary catheter and the importance of time to physiological stability. An intervention targeting avoidance of urinary catheters may be associated with a shorter LOS.

Age Factors↗

Relationship between alexithymia, dissociation and personality in psychiatric outpatients.

BACKGROUND: The relationship between alexithymia and dissociation is not known. Both mechanisms ward off overwhelming affective states; hence, this report examines the relationship between dissociation, alexithymia, depressed mood and the five-factor model of personality in a sample of psychiatric outpatients. METHODS: One hundred and sixteen outpatients were evaluated using the Toronto Alexithymia Scale (TAS), the Dissociative Experiences Scale (DES), NEO Five-Factor Inventory and visual analog scales assessing depression and anxiety. Data was analyzed using multivariate analysis of variance, logistic regression and linear regression techniques. RESULTS: Depressed mood accounted for the group differences between the global TAS and DES scores. Using DES both dimensionally and categorically with regression models, there was minimal contribution of DES or its subfactors to predict TAS. CONCLUSIONS: These data reaffirm previous findings that dissociation fundamentally differs from alexithymia. Dissociation involves a change of one's sense, of self, whereas alexithymia reflects a cognitive state of externally oriented thinking with an inability to identify and report discrete emotions.

Adult↗

Progression of chronic renal failure.

The different modes of progression of renal diseases were studied in 73 patients by plotting the reciprocals (1/SCr) and logarithms (logSCr) of their serum creatinine values against time. The regression was linear in the reciprocal plot for 42 patients (57.5%) and in the logarithmic plot for 12 patients (16.4%). The type of renal disease did not predict the mode of progression. The deviations from the linear regression lines were probably most often due to changes in the level of blood pressure and to intensification of treatment for hypertension. The reciprocal plot turned out to be useful for predicting the date when end-stage renal failure was reached. An accuracy of 4 months was reached in 81.5% using the reciprocal plot but only in 25.9% using the logarithmic plot.

Adult↗

Race and sex differences in the correlates of blood pressure change.

Potential predictors of systolic and diastolic blood pressure change between 1960 and 1967 in the biracial population of Evans County, Georgia, were investigated. An all possible regressions multiple linear regression analysis was used. For systolic blood pressure change, the level of systolic blood pressure, age, and change in Quetelet index were significant (p less than 0.05) correlates in white men. The level of systolic blood pressure, the level and change of socioeconomic status, change in Quetelet index, and change in cholesterol were significant correlates for white women. The level of Quetelet index was of borderline significance (p less than 0.055) when the other significant variables were included in the model for white women. The change in Quetelet index was the only significant correlate of systolic blood pressure change in blacks. For diastolic blood pressure change, age, change in hematocrit, and change in Quetelet index were significant correlates for white men. Age, level and change of socioeconomic status, level and change of Quetelet index, and change in hematocrit were the significant correlates in white women. In black men, change in Quetelet index and age were significant. In black women, only age was a significant correlate of diastolic blood pressure change. These results indicate that there may be important differences in these correlates between race-sex groups and thus in the mechanism of blood pressure change for different race-sex groups. groups.

Adult↗

Acculturation and socioeconomic position as predictors of coronary calcification in a multiethnic sample.

BACKGROUND: Coronary calcium has recently emerged as a marker of subclinical coronary heart disease. Although there has been much interest in race differences in calcification, heterogeneity within race or ethnic groups has not been investigated. METHODS AND RESULTS: Data from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based study of coronary calcification, were used to investigate acculturation and socioeconomic position as predictors of coronary calcification within 2553 non-Hispanic whites, 1734 non-Hispanic blacks, 1457 Hispanics, and 797 Chinese residing in the United States. Coronary calcium was assessed by chest CT. Relative risk regression and linear regression were used to estimate adjusted associations of sociodemographic variables with the presence and amount of calcium. Not being born in the United States was associated with a lower prevalence of calcification in blacks (relative prevalence [RP], 0.75; 95% confidence limit [CL], 0.61 to 0.94) and Hispanics (RP, 0.89; 95% CL, 0.81 to 0.98) after adjustment for age, sex, income, and education. Years in the United States was positively associated with prevalence of calcification in non-US-born Chinese (adjusted RP per 10 years in United States, 1.06; 95% CL, 1.01 to 1.11) and non-US-born blacks (RP, 1.59; 95% CL, 1.22 to 2.06). Low education was associated with a higher prevalence of calcification in whites (adjusted RP for no high school versus complete college, 1.17; 95% CL, 1.05 to 1.32) but with lower prevalence of calcification in Hispanics (RP, 0.91; 95% CL, 0.77 to 1.09) (P for interaction=0.02). US birth and time in the United States were also positively associated with the extent of calcification in persons with detectable calcium. These differences did not appear to be accounted for by smoking, body mass index, LDL and HDL cholesterol, hypertension, and diabetes. CONCLUSIONS: Acculturation and socioeconomic factors are associated with differences in the prevalence and amount of coronary calcification within whites, Chinese, blacks, and Hispanics. The presence of this heterogeneity needs to be acknowledged in the quantification and investigation of race/ethnic differences.

Acculturation↗

Detecting outliers when fitting data with nonlinear regression - a new method based on robust nonlinear regression and the false discovery rate.

BACKGROUND: Nonlinear regression, like linear regression, assumes that the scatter of data around the ideal curve follows a Gaussian or normal distribution. This assumption leads to the familiar goal of regression: to minimize the sum of the squares of the vertical or Y-value distances between the points and the curve. Outliers can dominate the sum-of-the-squares calculation, and lead to misleading results. However, we know of no practical method for routinely identifying outliers when fitting curves with nonlinear regression. RESULTS: We describe a new method for identifying outliers when fitting data with nonlinear regression. We first fit the data using a robust form of nonlinear regression, based on the assumption that scatter follows a Lorentzian distribution. We devised a new adaptive method that gradually becomes more robust as the method proceeds. To define outliers, we adapted the false discovery rate approach to handling multiple comparisons. We then remove the outliers, and analyze the data using ordinary least-squares regression. Because the method combines robust regression and outlier removal, we call it the ROUT method. When analyzing simulated data, where all scatter is Gaussian, our method detects (falsely) one or more outlier in only about 1-3% of experiments. When analyzing data contaminated with one or several outliers, the ROUT method performs well at outlier identification, with an average False Discovery Rate less than 1%. CONCLUSION: Our method, which combines a new method of robust nonlinear regression with a new method of outlier identification, identifies outliers from nonlinear curve fits with reasonable power and few false positives.

Computer Simulation↗

Surveillance of duodenal adenomas in familial adenomatous polyposis reveals high cumulative risk of advanced disease.

PURPOSE: The development of high-grade dysplasia (HGD) on duodenal or jejunal adenomas and of late-stage (stage IV) duodenal polyposis are major clinical events for familial adenomatous polyposis (FAP) patients. Our aim was to determine their respective frequency, risk factors, and cumulative risk. PATIENTS AND METHODS: A prospective, optimized, endoscopic surveillance protocol was applied to 58 FAP patients in a university hospital. The number, size, and histology of duodenojejunal polyps were assessed, and the Spigelman's score was calculated at each endoscopy. Cox regression and linear regression analysis were used to determine risk factors for HGD development and the cumulative risk of stage IV duodenal polyposis, respectively. RESULTS: During a median (+/- standard deviation) follow-up of 47.9 +/- 15.6 months, 35 patients with at least two consecutive examinations had 107 duodenojejunal examinations. The Spigelman's score increased in 21 patients (60.0%), and HGD developed in 12 patients (34.2%). High initial Spigelman's score (> 7 points), but not age or APC mutation site, was a risk factor for HGD development. Estimated cumulative risk of developing stage IV duodenal polyposis was of 42.9% at age 60 (95% CI, 35.7% to 50.0%) and 50.0% at age 70 (95% CI, 42.9% to 57.1%). CONCLUSION: This prospective series shows a higher duodenal polyposis progression rate and cumulative risk of late-stage (stage IV) duodenal polyposis in FAP patients compared with previous series. These results suggest that current modalities for surveillance and management of these patients need revision.

Adenoma↗

[Development and evaluation of a spectroscopy system for classification of laser-induced arterial fluorescence spectra].

The present study evaluated the potential of fluorescence guidance of laser angioplasty without using a second laser for fluorescence excitation. A prototype spectroscopy system with a grating spectrograph, microchannel plate, CCD array and digital image processor on a personal computer was developed and coupled to a clinical XeCl excimer laser. Using multifibre catheters, specimens of human aorta were ablated in physiological saline and blood. The spectra thus generated were recorded and validated histologically. Five types of spectra could be differentiated. Based on a training set, classification algorithms were developed using multiple linear regression and linear discriminant analysis with intensity ratios as predictor variables. Discriminant analysis yielded prospective classification of the remaining validation spectra with high sensitivity and specificity for each type. These data demonstrate that fluorescence spectroscopy during excimer laser ablation at 308 nm does not require a diagnostic laser. Principal types of atherosclerotic lesions and the media can be differentiated spectroscopically in physiological saline and blood.

Adult↗

Practical implications of coexistent different technologies in clinical chemical laboratories. Solid phase chemistry and conventional analysis.

If different analytical methods are alternatively used for the determination of the same analyte, basic differences in test methodology can give rise to an increased number of deviating results. Such coexistence of methods might be necessary, for example, during a transition phase while upgrading to new technologies. We have exemplarily investigated this topic for the comparison of solid phase chemistry ("dry chemistry") versus conventional methods ("wet chemistry"). The Kodak Ektachem 700XR clinical chemistry analyser was compared with the Hitachi 737 analyser from Boehringer Mannheim using 18 clinical chemical analytes and specimens submitted for routine analysis. Before the start of the evaluation, the Ektachem 700XR was adjusted ("calibrated") by the manufacturer for optimal agreement with the Hitachi 737. Satisfactory agreement was obtained for most investigated analytes as judged by correlation coefficients and three commonly applied regression methods (linear regression, principal components, and Passing/Bablok method). For some analytes, however, strongly deviating results were often obtained. Quality control-derived limits (maximum acceptable inaccuracy) and data from biological variation (critical differences) were used for the assessment of the inter-instrument bias for diagnosis and patient monitoring, respectively. For enzymes, 0% (amylase) to 22% (creatine kinase) of all pathologic results differed by more than the maximum acceptable analytical inaccuracy (21%-27%) of these analytes. If more stringent limits derived from biological variation were used, 24% (creatine kinase)--62% (aspartate aminotransferase) of all differences between paired measurements exceeded the critical difference for enzymes. Deviations greater than the critical differences were also marked for serum concentrations of sodium, calcium, and creatinine.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Chemical Analysis↗

Changes in the sonographic appearance of the uterus after discontinuation of tamoxifen therapy.

OBJECTIVE: The purpose of this study was to assess the duration of sonographically detected changes in the endometrium of women with a history of tamoxifen use. METHODS: Patients with breast cancer who had a history of tamoxifen use and documented pelvic sonographic studies were identified by means of clinic databases in both the Section of Gynecological Oncology and the Section of Obstetrical and Gynecological Ultrasound, University of Chicago, between January 1, 1996, and March 30, 2004. Of the 99 patients who met study criteria, 34 had discontinued tamoxifen use before the sonographic evaluation. Each patient's age, gravity and parity, weight, ethnicity, duration and dose of drug use, interval from drug discontinuation until sonographic evaluation, and uterine pathologic findings were reviewed. Endometrial thickness as assessed by pelvic sonography was examined in relation to duration of tamoxifen use and time from discontinuation of the drug. Statistical analysis was performed with linear regression and mixed effect linear regression models. RESULTS: Endometrial thickness increased with increasing duration of tamoxifen use at a rate of 0.75 mm/y. The mean endometrial thickness after approximately 5 years of tamoxifen use was 12 mm (range, 6-21 mm). After discontinuation of tamoxifen, endometrial thickness decreased by 1.27 mm/y. CONCLUSIONS: Endometrial thickness as measured by pelvic ultrasound examination increases with the duration of tamoxifen use. After discontinuation of the drug, the measured thickness decreases but at a very slow rate.

Antineoplastic Agents, Hormonal↗