Biomedical subjects

Alison M Duncan

Publications and source records attributed to Alison M Duncan.

17 recordsLinked to original sources

PubMed2006

Comparison of segmental and global markers of dyssynchrony in predicting clinical response to cardiac resynchronization.

AIMS: Cardiac resynchronization therapy (CRT) reduces inter- and intraventricular dyssynchrony and shortens total isovolumic time (t-IVT). We compared the extent to which the values of ventricular dyssynchrony and t-IVT predict clinical benefits of CRT. METHODS AND RESULTS: Ventricular dyssynchrony was assessed in 39 patients with heart failure before and 6 months after CRT. Segmental dyssynchrony was identified from time to onset and peak systolic velocity of wall motion. T-IVT (s/min) was derived as [60-(total ejection time+total filling time)]. The difference between ventricular pre-ejection periods (D-PEP) was calculated. Outcome measures were fall in New York Heart Association (NYHA) class and increase in cardiac output (CO). Following CRT, NYHA class fell in 29/39 patients, CO increased (by 1.0 L/min, P < 0.001), and intraventricular delay (Intra-VD), interventricular delay (Inter-VD), t-IVT, and D-PEP shortened (by 25 ms, 72 ms, 6 s/min, and 38 ms, P < 0.01). NYHA class and CO were unchanged with CRT in 10/39, and Intra-VD, Inter-VD, t-IVT, and D-PEP lengthened (by 43 ms, 52 ms, 7 s/min, and 35 ms, P < 0.05). Though univariate predictors of CO increment with CRT were Intra-VD, Inter-VD, t-IVT, and D-PEP, only pre-CRT values of CO (P < 0.001), t-IVT (P < 0.001), and D-PEP (P = 0.025) were independent. CONCLUSION: Global, rather than segmental, measures of ventricular dyssynchrony are powerful, independent predictors of clinical response to CRT.

Aged↗

PubMed2006

Effect of soy protein varying in isoflavone content on serum lipids in healthy young men.

BACKGROUND: Previous research supports a role for soy protein in reducing serum lipids; however, few studies involved healthy male subjects or focused on soy isoflavones (or did both). OBJECTIVE: The objective was to ascertain the effects of soy protein varying in isoflavone content on serum lipids in healthy young men. DESIGN: Thirty-five males (x +/- SD age: 27.9 +/- 5.7 y) consumed milk protein isolate (MPI), low-isoflavone soy protein isolate (low-iso SPI; 1.64 +/- 0.19 mg aglycone isoflavones/d), and high-isoflavone SPI (high-iso SPI; 61.7 +/- 7.4 mg aglycone isoflavones/d) for 57 d each, separated by 4-wk washout periods, in a randomized crossover design. Blood samples were collected at the beginning and end of each treatment period, and total, LDL, and HDL cholesterol; triacylglycerols; apolipoprotein (apo) B; apo A-I; and C-reactive protein (CRP) were measured in serum. Twenty-four-hour urine samples were collected for 3 consecutive days at the end of each treatment period and analyzed for isoflavones. RESULTS: Urinary isoflavones were significantly greater with consumption of the high-iso SPI than with that of the low-iso SPI or MPI. The differences between the 3 treatments with respect to individual serum lipids were not significant, but the ratios of total to HDL cholesterol, LDL to HDL cholesterol, and apo B to apo A-I were significantly lower with both SPI treatments than with MPI treatment. CONCLUSION: Soy protein, regardless of isoflavone content, modulates serum lipid ratios in a direction beneficial for cardiovascular disease risk in healthy young men.

Adult↗

PubMed2005

Effect of dobutamine stress on left ventricular filling in ischemic dilated cardiomyopathy: pathophysiology and prognostic implications.

OBJECTIVES: The purpose of this research was to study the effect of dobutamine on left ventricular (LV) filling in ischemic cardiomyopathy (ICM) and to determine whether restrictive filling pattern (RFP) at peak stress has prognostic value. BACKGROUND: The prognostic value of RFP at peak stress in ICM is unknown. METHODS: A total of 69 patients with ICM were studied by Doppler echocardiography at rest and stress; RFP was defined as transmitral E:A ratio > or =1.0, isovolumic relaxation time (IVRT) <80 ms, and E-wave deceleration time (EDT) <120 ms. RESULTS: A total of 42 of 69 had RFP at rest, which reverted to non-RFP at stress in 24 (EA), but persisted in 18 (EE); 27 of 69 had non-RFP at rest and peak stress (AA). In EA, IVRT and EDT lengthened (by 43 ms and 46 ms), and tricuspid regurgitation (TR) decreased (by 26 mm Hg, p < 0.01), suggesting a fall in left atrial (LA) pressure. The stress response in AA was similar to EA. In EE, IVRT and EDT shortened (by 21 ms) and TR increased (by 13 mm Hg, p < 0.01), suggesting a rise in LA pressure. Peak aortic acceleration (LV inotropy) increased by 0.8 g in EA but only by 0.2 g in EE (difference p < 0.001). Median follow-up (interquartile range) was 34 (20 to 57) months. Three-year survival for EE, EA, and AA was 49%, 79%, and 89%, respectively (p < 0.001). Compared with AA, the hazard ratio for EE was 9.5 (p < 0.001) and for EA was 1.9 (p = 0.30). CONCLUSIONS: In ischemic cardiomyopathy, persistence of restrictive filling during stress implies a striking rise in LA pressure, greatly attenuated LV inotropic response, and markedly reduced survival. Stress echocardiography uniquely identifies these high-risk patients.

Aged↗

PubMed2005

Opposite effects of coronary artery disease and hypertrophic cardiomyopathy on left ventricular long axis function during dobutamine stress.

BACKGROUND: The mechanism for reduced early diastolic long axis lengthening velocity in hypertrophic cardiomyopathy (HCM) is not known. METHODS: We measured simultaneous septal long axis amplitude and early lengthening velocity in 23 patients with HCM, 23 normal subjects and 22 patients with coronary artery disease (CAD) of left anterior descending artery. RESULTS: Resting amplitude and lengthening velocity were reduced in HCM 0.9+/-0.2 cm, 3.5+/-1.9 cm/s but equally in CAD 1.0+/-0.3 cm, 4.1+/-2.5 cm/s vs. 1.3+/-0.2 cm, 6.3+/-1.7 cm/s in normals, p < 0.01 for both vs. normal. With dobutamine stress, lengthening velocity increased by 2.7+/-1.9 cm/s (p < 0.001) in normals, by 2.8+/-2.5 cm/s (p < 0.001) in HCM but not in patients with CAD 0.5+/-2.1, p = NS. Increment in total long axis amplitude was subnormal in CAD and HCM. However, increment in lengthening velocity was higher with stress for corresponding change in amplitude in HCM compared with CAD (chi2) = 16.5, p < 0.001). An increase in early lengthening velocity by 2 cm/s was 77% sensitive and 70% specific in discriminating between HCM and CAD. Post-ejection shortening developed or worsened in all CAD patients indicating ischemia but not in any with HCM. CONCLUSIONS: Reduced peak early lengthening velocity is not specific for HCM but also occurs in CAD. Unlike CAD, lengthening velocity increases in HCM with stress and there is no aggravation of post-ejection shortening, suggesting that the abnormal relaxation is not due to subendocardial ischemia in HCM. The greater recoil velocity per unit deformation in HCM compared with CAD, indicates elastic mechanism with increased passive muscle stiffness due to fibrosis or fibre disarray.

Cardiomyopathy, Hypertrophic↗

PubMed2005

Prevalence of dietary supplement use in adults with chronic renal insufficiency.

OBJECTIVE: There are currently no studies that have investigated dietary supplement use in the chronic renal insufficiency (CRI) population. The objectives of this study were to determine the prevalence of dietary supplement use in a sample of adults with CRI and to examine whether the prevalence of dietary supplement use was higher in the earlier stages of CRI. DESIGN AND SETTING: Cross-sectional survey conducted at an outpatient nephrology clinic. PATIENTS: Adults (n = 100) with varying degrees of CRI. INTERVENTION: Interview-administered questionnaire. MAIN OUTCOME MEASURES: The questionnaire contained questions related to the use of dietary supplements, attitudes, and beliefs about dietary supplements, as well as medical and demographic data including gender, age, body weight, smoking status, concurrent chronic conditions, prescribed medications, serum creatinine, estimated glomerular filtration rate (GFR), etiology of CRI, income, and education level. RESULTS: The prevalence of dietary supplement use was 45%, with the most frequent use occurring in subjects with a mild to moderate degree of renal insufficiency. There were no significant differences in gender, age, body mass index, smoking status, number of concurrent chronic conditions, number of prescribed medications, income, or education level between supplement users and supplement nonusers. Further analysis of dietary supplement use showed that the number of supplements used ranged from 1 to 5 or more supplements per day, with an overall total of 36 different supplements. Dietary supplement users were significantly more concerned with their health than were supplement nonusers. The most frequent sources of supplement information were physicians and printed material; however, 75% of the dietary supplement users desired further information about their dietary supplements. CONCLUSION: This is the first study to investigate the use of dietary supplements in adults with CRI, and it provides valuable information for health care professionals regarding the dietary supplement use of their patients with CRI.

Aged↗

PubMed2005

Soy protein isolates of varying isoflavone content exert minor effects on serum reproductive hormones in healthy young men.

Inverse associations between soy and prostate cancer and the contribution of hormones to prostate cancer prompted the current study to determine whether soy protein could alter serum hormones in men. Thirty-five men consumed milk protein isolate (MPI), low-isoflavone soy protein isolate (SPI) (low-iso SPI; 1.64 +/- 0.19 mg isoflavones/d), and high-iso SPI (61.7 +/- 7.35 mg isoflavones/d) for 57 d each in a randomized crossover design. Twenty-four-hour urine samples indicated that urinary isoflavones were significantly increased by the high-iso SPI relative to the low-iso SPI and MPI. Serum collected on d 1, 29, and 57 of each treatment revealed that dihydrotestosterone (DHT) and DHT/testosterone were significantly decreased by the low-iso SPI [9.4% (P = 0.036) and 9.0% (P = 0.004), respectively] and the high-iso SPI [15% (P = 0.047) and 14% (P = 0.013), respectively], compared with the MPI at d 57. Other significant effects included a decrease in testosterone by the low-iso SPI relative to the MPI (P = 0.023) and high-iso SPI (P = 0.020) at d 29; an increase in dehydroepiandrosterone sulfate by the low-iso SPI relative to the MPI at d 29 (P = 0.001) and relative to the MPI (P = 0.0003) and high-iso SPI (P = 0.005) at d 57; and increases in estradiol and estrone by the low-iso SPI relative to the MPI at d 57 (P = 0.010 and P = 0.005, respectively). In conclusion, soy protein, regardless of isoflavone content, decreased DHT and DHT/testosterone with minor effects on other hormones, providing evidence for some effects of soy protein on hormones. The relevance of the magnitude of these effects to future prostate cancer risk requires further investigation.

Adult↗

PubMed2004

Comparison of energy and nutrient intakes among meals and snacks of adolescent males.

BACKGROUND: Eating behaviors developed during adolescence can have immediate health implications and influence future chronic disease risk. The objectives of this study were to determine and compare the distribution of energy and nutrient intakes among meals and snacks, and relate eating occasion frequency to body mass index (BMI) of adolescent males. METHODS: Healthy adolescent males (n = 180) completed 3-day food records. Following analysis for energy and nutrient intakes, 3-day averages and frequencies were computed for all meals and snacks. RESULTS: Dinner was the largest contributor of energy, macronutrients, cholesterol, dietary fiber, and sodium, whereas both dinner and breakfast were the largest contributors of calcium and iron. On average, subjects consumed 1.63 snacks/day, with 77% consuming > or = 1 snack/day. BMI was significantly greater and energy intake was significantly lower in subjects having < or = 3 eating occasions/day relative to 4 or > or = 6 eating occasions/day. The 26% of subjects classified as inconsistent breakfast consumers had significantly higher BMIs and lower iron intakes relative to consistent breakfast consumers. CONCLUSIONS: This study provides valuable information regarding eating occasion frequency and contribution of meals and snacks to energy and nutrient intakes in adolescent males. Such information could be used to improve nutrition education programs for adolescents aimed at chronic disease prevention.

Adolescent↗

PubMed2004

Limitation of exercise tolerance in chronic heart failure: distinct effects of left bundle-branch block and coronary artery disease.

OBJECTIVES: The aim of this study was to identify resting measurements of left ventricular (LV) function that predict exercise capacity in dilated cardiomyopathy (DCM); in particular, the effects of left bundle branch block (LBBB), coronary artery disease (CAD), and total isovolumic time (t-IVT). BACKGROUND: The t-IVT is a major determinant of cardiac output during dobutamine stress in DCM, and is itself determined by the presence or absence of LBBB and CAD. METHODS: A total of 111 patients with DCM, 51 with CAD (29 LBBB), and 60 without CAD (30 LBBB) were studied with echocardiography and cardiopulmonary exercise testing. The t-IVT (in s/min) was measured by Doppler echocardiography, and maximal oxygen consumption (peak Vo(2)) and percentage of the normal predicted peak Vo(2) (%predicted peak Vo(2)) were obtained from exercise testing. RESULTS: Left bundle branch block reduced peak Vo(2) (by 10.5 ml.kg(-1)min(-1)) and %predicted peak Vo(2) (by 33%, both p < 0.001) compared with patients without LBBB. Coronary artery disease reduced peak Vo(2) (by 5.5 ml.kg(-1)min(-1), p < 0.001) and %predicted peak Vo(2) (by 14%, p < 0.01) compared with those without CAD (p < 0.01). The t-IVT, CAD, LBBB, and QRS duration were univariate predictors of exercise tolerance, but only t-IVT and CAD were independent predictors. The t-IVT at rest correlated with peak Vo(2) (r = -0.68) and %predicted peak Vo(2) (r = -0.74, both p < 0.001). The combination of t-IVT and CAD explained 57% (r = 0.75, p < 0.001) of the total variance in exercise capacity. CONCLUSIONS: Resting t-IVT and less prominently, CAD, are major determinants of exercise tolerance in DCM. Left bundle branch block significantly determines resting t-IVT and thus peak Vo(2). Prediction of maximum exercise capacity in DCM is therefore possible from time-domain analysis of LV function at rest.

Adrenergic beta-Antagonists↗

PubMed2004

Systole-diastole mismatch in hypertrophic cardiomyopathy is caused by stress induced left ventricular outflow tract obstruction.

BACKGROUND: Pharmacological stress is used to assess the degree of left ventricular (LV) subvalvular gradient in patients with hypertrophic cardiomyopathy (HCM), but there is little information about associated physiological changes. METHODS: Echocardiography-Doppler ultrasound scanning measurements in 23 patients with HCM and 23 control subjects of similar age were studied at rest and at the end point of dobutamine stress. RESULTS: In patients, the systolic time was normal at rest, but increased abnormally with stress. In patients, the total isovolumic contraction time failed to shorten, and the total ejection time increased abnormally. Changes in total ejection time correlated with an increase in peak subvalvular gradient in control subjects and patients (r = 0.52 and r = 0.66, respectively; P <.01 for both). In patients, the diastolic time was normal at rest, but shortened abnormally with stress. In patients, the isovolumic relaxation time fell abnormally, as did the filling time. Mitral E wave acceleration and left atrium size were unchanged with stress in control subjects, but consistently increased in patients with HCM, which indicates an increased early diastolic atrioventricular pressure gradient. CONCLUSION: In HCM, systolic period increases abnormally with stress. This is not because of a loss of inotropy, but is directly related to the degree of LV outflow tract obstruction. As a result, the diastolic period fails to increase, reducing the time available for coronary flow, the LV filling pattern is modified, and the diastolic atrioventricular pressure gradient increases. These changes may contribute to symptom development and suggest why reducing LV outflow tract obstruction per se may be therapeutically useful in HCM.

Cardiomyopathy, Hypertrophic↗

PubMed2004

Importance of left ventricular activation in determining myocardial performance (Tei) index: comparison with total isovolumic time.

BACKGROUND: The Tei index is commonly used as a measure of "combined systolic and diastolic function". A sensitive and specific index of intrinsic myocardial contraction and relaxation would be independent of abnormal activation. We aimed to determine whether the Tei index fulfils this criterion in patients with normal activation or left bundle branch block (LBBB), normal or dilated left ventricular (LV) cavities, with or without coronary artery disease (CAD). METHODS: We studied 32 controls and 124 patients; 49 had CAD and normal LV size (11 LBBB), 27 had non-ischaemic dilated cardiomyopathy (DCM, 11 LBBB), and 48 had ischaemic DCM (17 LBBB). Tei index (isovolumic contraction time+isovolumic relaxation time/ejection time) and total isovolumic time (t-IVT: [60-(total ejection time+total filling time]) were measured using Doppler echocardiography. RESULTS: Tei index and t-IVT were prolonged in LBBB (by 0.6 and 9.1 s/min, P<0.001). T-IVT identified LBBB with greater predictive accuracy than Tei index (sensitivity 97% vs. 90%, specificity 93% vs. 91%, P<0.05). Tei index and t-IVT were also prolonged in DCM (by 0.2 and 3.1 s/min, both P<0.001). Although Tei index identified DCM with sensitivity 71%, this fell to 53% when LBBB was excluded (P<0.05). CAD had no effect on Tei index or t-IVT. CONCLUSIONS: The Tei index is not a measure of intrinsic myocardial systolic and diastolic function, since its main determinant is ventricular activation rather than cavity size. T-IVT, however, is more sensitive to activation, is unrelated to cavity size or CAD, and may thus be a more accurate measure of the mechanical consequences of ventricular activation in a variety of cardiac conditions.

Aged↗

PubMed2004

Caffeine ingestion increases the insulin response to an oral-glucose-tolerance test in obese men before and after weight loss.

BACKGROUND: Caffeine ingestion decreases the insulin sensitivity index (ISI) for an oral-glucose-tolerance test (OGTT) and decreases insulin-induced glucose disposal in lean male subjects during a hyperinsulinemic clamp. OBJECTIVE: We examined the effects of caffeine ingestion on insulin and glucose homeostasis in obese men before and after a nutrition and exercise intervention. DESIGN: Nine sedentary, obese [body mass index (in kg/m(2)): 34.0 +/- 1.0] men who had refrained from exercise and caffeine ingestion for 48 h underwent 2 oral-glucose-tolerance tests (OGTTs). The subjects randomly received caffeine (5 mg/kg) or placebo 1 h before each OGTT. After a 12-wk nutrition and exercise intervention, during which time the subjects avoided dietary caffeine, the OGTTs were repeated. RESULTS: The intervention resulted in decreases (P < or = 0.05) in body weight (8.5 +/- 1.5 kg), percentage body fat (2.8 +/- 0.7%), and fasting glucose, insulin, and proinsulin concentrations and increases in the ISI for the placebo OGTT (P < or = 0.05). Caffeine caused a greater (P < or = 0.05) OGTT insulin response and a lower (P < or = 0.05) ISI both before and after weight loss. The proinsulin-insulin ratio indicated that neither weight loss nor caffeine affected the nature of the beta cell secretion of insulin. CONCLUSIONS: A nutrition and exercise intervention improved, whereas caffeine ingestion impaired, insulin-glucose homeostasis in obese men. The results are consistent with previous findings that caffeine ingestion contributes to insulin resistance.

Administration, Oral↗

PubMed2003

Differentiation of ischemic from nonischemic cardiomyopathy during dobutamine stress by left ventricular long-axis function: additional effect of left bundle-branch block.

BACKGROUND: Resting regional wall-motion abnormalities do not reliably distinguish ischemic from nonischemic cardiomyopathy. Dobutamine stress echocardiography with use of the wall-motion score index (WMSI) identifies coronary artery disease (CAD) in dilated cardiomyopathy (DCM), but the technique is subjective and further complicated by left bundle-branch block (LBBB). Long-axis motion is sensitive to ischemia and can be assessed quantitatively. We aimed to compare long-axis function with WMSI for detecting CAD in DCM with or without LBBB. METHODS AND RESULTS: Seventy-three patients with DCM, 48 with CAD (16 with LBBB), and 25 without CAD (10 with LBBB) were studied. Long-axis M-mode, pulsed-wave tissue Doppler echograms (lateral, septal, and posterior walls), and WMSI were assessed at rest and at peak dobutamine stress. Failure to increase systolic amplitude (total amplitude minus postejection shortening) by 2 mm or early diastolic velocity by 1.1 cm/s was the best discriminator for CAD (systolic amplitude, sensitivity 85%, specificity 86%; lengthening velocity, 71% and 94%, respectively; P=NS). Both had greater predictive accuracy than did WMSI (sensitivity 67%, specificity 76%; P<0.001). The predictive accuracy of changes in septal long-axis function was similar to those of average long-axis function (systolic amplitude cutoff=1.5 mm, lengthening velocity cutoff=1.5 cm/s). However in LBBB, systolic amplitude proved to be the only significant discriminator for CAD, with sensitivity and specificity reaching 94% and 100%, respectively (P<0.01 versus early diastolic lengthening velocity). CONCLUSIONS: Quantified stress long-axis function identifies CAD in DCM with greater sensitivity and specificity than does standard WMSI, particularly in the presence of LBBB.

Bundle-Branch Block↗

PubMed2003

Limitation of cardiac output by total isovolumic time during pharmacologic stress in patients with dilated cardiomyopathy: activation-mediated effects of left bundle branch block and coronary artery disease.

OBJECTIVES: We sought to separate the effects of associated left bundle branch block (LBBB) and coronary artery disease (CAD) on peak cardiac output (CO) during dobutamine stress in patients with dilated cardiomyopathy (DCM). BACKGROUND: The mechanisms limiting CO during stress in patients with DCM are unclear. Both LBBB and CAD may do so by prolonging the total isovolumic time (t-IVT). METHODS: A total of 59 patients with DCM-34 with CAD (20 normal activation [NA], 14 LBBB) and 25 without CAD (15 NA, 10 LBBB)-were studied. The total IVT (s/min; calculated as: 60 - [total ejection time + total filling time] ) and CO were measured by Doppler echocardiography. RESULTS: At rest, t-IVT was 8 s/min longer with LBBB (p < 0.001), was unaffected by CAD, and did not correlate with rest CO. During stress, CO correlated with t-IVT (r = -0.73, p < 0.001) in all four patient groups. In the absence of CAD, t-IVT became shortened (NA by 7 +/- 3 s/min; LBBB by 9 +/- 4 s/min) and correlated with a fall in the QRS duration (NA: r = 0.87; LBBB: r = 0.91), and CO increased with stress (NA by 4.7 +/- 2.7 l/min; LBBB by 4.0 +/- 2.3 l/min; all p < 0.001). With CAD, t-IVT did not shorten normally with stress. Instead, t-IVT was 5.6 s/min longer and CO was 3.3 l/min lower than in those without CAD (both p < 0.001), and t-IVT did not correlate with the QRS duration. CONCLUSIONS: In patients with DCM, t-IVT during pharmacologic stress depends on changes in ventricular activation induced by LBBB or CAD and is, by itself, a major determinant of peak CO during stress.

Aged↗

PubMed2003

Phyto-oestrogens.

Phyto-oestrogens are oestrogenic compounds found in plants and consist of isoflavones, lignans and coumestans. Epidemiological studies provide evidence for a protective role of isoflavones, and to a lesser extent lignans, against the development of numerous chronic diseases, including several cancers, cardiovascular disease and osteoporosis. The structural similarity of phyto-oestrogens to endogenous oestrogens has prompted the hypothesis that phyto-oestrogens exert hormonal or anti-hormonal effects relevant to the risk of hormone-dependent disease and/or their suitability as a dietary alternative to hormone replacement therapy. The many human studies that have evaluated the effects of isoflavones and lignans on various endpoints relating to risk of various diseases have greatly increased knowledge of how these compounds behave. At the same time, additional questions have been generated. For example, the increasing interest in extracting isoflavones from the soybean for incorporation into dietary supplements has raised important concerns regarding safety and efficacy. Overall, it is clear that phyto-oestrogens are an area of active and advancing research with great potential to continue to affect human health.

Animals↗

PubMed2002

Isoflavones and postmenopausal women: a critical review.

Isoflavonic phytoestrogens, or isoflavones, constitute a class of phytoestrogens that have properties similar to selective estrogen receptor modulators, and have attracted a substantial degree of attention in recent years, particularly as a possible alternative to the conventional hormone replacement therapy regimens used by postmenopausal women. Despite great promise, it is difficult to make many specific recommendations about their use at the current time, in light of the many outstanding questions that hopefully will be answered in the future by focused interventional studies involving humans. Studies to date indicate that the use of isoflavones to address vasomotor symptoms provides at most small benefits beyond a placebo effect, and no benefit for genital atrophy. As for postmenopausal women whose primary concern is cardiovascular disease, the recommendation of the American Heart Association to include soy protein foods as part of an otherwise healthy diet is well justified, and similarly the substitution of supplements containing soy protein for animal protein can also be recommended. The use of purified isoflavone supplements not containing soy protein may have some cardiovascular benefits, but these appear to be less substantial in degree than those provided by soy protein with isoflavones. In particular, more research is needed to assess the effects of isoflavones on osteoporosis, for which no recommendation regarding isoflavones can be made based on the current data. Also, isoflavones should not be taken by postmenopausal women for the specific purpose of decreasing their risk of breast or endometrial cancer, although, at least for those without pre-existing disease or at high risk, it seems quite unlikely that isoflavone use is harmful in this regard.

Cardiovascular Diseases↗

PubMedDate not supplied

The role of nutrition in the prevention of breast cancer.

Nutrition has been widely studied as a leading environmental factor in the prevention of breast cancer (BC). Despite the challenges in relating consumption of specific nutrients to BC risk, particularly in the context of a total diet, many investigators have contributed valuable information. Dietary fat has received the most attention and also created the most uncertainty. Specific types of fat, particularly monounsaturated fat and the ratio of omega-3 to omega-6 fatty acids, demonstrate more potential to influence BC risk. A wide variety of other dietary factors have been studied in relation to BC including total energy, dietary fiber, alcohol, micronutrients, phytochemicals, specific foods, and food constituents. Results of epidemiological studies relating consumption of these dietary factors to BC have increased the knowledge base that provides rationale for various nutritional strategies to contribute to BC prevention.

Breast Neoplasms↗

PubMedDate not supplied

Prevalence of natural health product use in healthy postmenopausal women.

OBJECTIVES: Population studies examining dietary supplement use reveal that users are more likely to be women of older age, yet there are few focused studies among postmenopausal women. The purpose of this study was to determine the prevalence of natural health product (NHP) use, as well as the attitudes and motivations associated with NHP use, among postmenopausal women. DESIGN: Healthy postmenopausal women were recruited from shopping malls and community centers to complete a questionnaire that collected information regarding use of NHPs; attitudes and motivations about NHPs; and demographic, health, and lifestyle characteristics. RESULTS: The prevalence of NHP use among the 204 subjects was 83.3%. There were no significant differences in characteristics between NHP users and non-users, with the exception of a lower body mass index among NHP users (P = 0.01). The most commonly consumed NHP was calcium, followed by multivitamins/minerals, vitamin C, and vitamin E. Almost all NHP users (98.8%) believed that NHPs improved their overall health, and most (70.6%) attributed specific positive effects to their NHPs. Three quarters of NHP users believed that their NHPs could not cause adverse effects, and 64.2% believed that their NHPs could not interact negatively with medications. The most common source of NHP information was magazines/books, and 71.8% of NHP users indicated they did not need further information about their NHPs. CONCLUSIONS: In this study, we found that the prevalence of NHP use among a sample of 204 healthy postmenopausal women was 83.3% and that, apart from body mass index, there were no variables that predicted NHP use.

Aged↗