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Amanda J Lee

Publications and source records attributed to Amanda J Lee.

35 records · Page 2Linked to original sources
PubMed2004

The obesity epidemic: both energy intake and physical activity contribute.

Recent data from Australia, the United States and Europe show increased self-reported energy intake associated with obesity, in contrast to earlier suggestions that the obesity epidemic has occurred despite minimal or no increase in per capita energy intake from food. The effect of increased energy intake is compounded by sedentary lifestyles. Both physical activity and nutrition must be addressed to reduce the prevalence of obesity and improve the health of Australians.

Adolescent↗
PubMed2004

Bypass versus angioplasty to treat severe limb ischemia: factors that affect treatment preferences of UK surgeons and interventional radiologists.

OBJECTIVE: There is continuing controversy as to whether surgical bypass or angioplasty should be first-line treatment of severe limb ischemia. We undertook this study to examine angiographic and clinical factors that influence the treatment of severe limb ischemia by vascular surgeons and interventional radiologists. METHODS: Twenty consultant vascular surgeons and 17 consultant vascular interventional radiologists evaluated 596 hypothetical clinical or angiographic scenarios, and recorded whether, in their opinion, the most appropriate first-line treatment was surgical bypass, angioplasty, or primary amputation. Stepwise multiple linear regression was used to identify the factors that significantly affected responses from the entire group and from surgeons and radiologists separately. RESULTS: There were significant differences between surgeons and radiologists with regard to how clinical and angiographic variables determined treatment preferences. Increasing disease severity, absence of runoff into the foot, presence of a suitable vein, and tissue loss as opposed to rest pain only (the latter only significant to surgeons) all increased the response score toward surgery. However, surgeons and radiologists weighted each of these factors quite differently. Even in the most complex statistical model, 19% of surgical and 13% of radiologic response variations remained unexplained. CONCLUSIONS: Individual surgeons and radiologists vary considerably in their views of the relative merits of surgery and angioplasty in patients with severe limb ischemia. This broad gray area mandates the need for randomized controlled trial data to inform joint decision-making and to optimize patient outcome.

Amputation, Surgical↗
PubMed2004

The health-related quality of life of people with peripheral arterial disease in the community: the Edinburgh Artery Study.

BACKGROUND: Previous studies investigating the health-related quality of life of those with peripheral arterial disease have focused on patients recruited from hospital clinics. The health-related quality of life of people with peripheral arterial disease in the general population is unknown. AIMS: We aimed to determine the health-related quality of life of people with intermittent claudication and asymptomatic peripheral arterial disease in the general population and to compare it with those with angina and those with no peripheral arterial disease or angina. DESIGN OF STUDY: Analysis of cross-sectional data from the 12-year follow-up of a population-based cohort. SETTING: Edinburgh, Scotland. METHOD: Data from the Edinburgh Artery Study cohort's 12-year follow-up was analysed. Participants' peripheral arterial disease status was measured using the World Health Organisation intermittent claudication questionnaire and the ankle brachial pressure index. Self-assessed health-related quality of life data was collected using the SF-36 generic questionnaire. Health-related quality of life scores were calculated and their associations with peripheral arterial disease status groups were tested. RESULTS: Subjects with intermittent claudication had significantly worse median health-related quality of life scores than patients without claudication in all domains except social functioning and mental health. Patients with claudication had a significantly lower physical component summary score than those without claudication (P </= 0.001). This association remained after adjustment for age, sex, social class, body mass index, smoking, and angina. Those with angina and claudication had significantly worse physical component summary scores than those with no peripheral arterial disease or angina (P </= 0.001). No significant difference was found in health-related quality of life scores between those with asymptomatic peripheral arterial disease and those with no peripheral arterial disease even after multiple adjustment for confounding factors. CONCLUSION: People with intermittent claudication in the community had impaired health-related quality of life related to reduced physical health, but asymptomatic peripheral arterial disease did not significantly affect health-related quality of life.

Aged↗
PubMed2003

Relationship of the platelet glycoprotein PlA and fibrinogen T/G+1689 polymorphisms with peripheral arterial disease and ischaemic heart disease.

INTRODUCTION: Genetic variation in plasma fibrinogen and the platelet receptor GP IIIa locus has been independently associated with increased risks of ischaemic heart disease, but there have been few reports on the relationship with peripheral arterial disease. This study determined the risk of peripheral arterial disease and ischaemic heart disease associated with polymorphisms of fibrinogen T/G(+1689) and platelet glycoprotein Pl(A) genes and the effects of cigarette smoking and fibrinogen. MATERIALS AND METHODS: In the 5-year follow-up phase of the Edinburgh Artery Study, 939 subjects (60-79 years) had DNA extracted from a venous blood sample. One hundred sixteen subjects were identified as having angina, 87 a myocardial infarction, 104 had intermittent claudication and 663 subjects comprised a healthy group. RESULTS: Distribution of the fibrinogen genotype was similar across the disease and healthy groups. Logistic regression analyses found no significant association between fibrinogen genotype and ischaemic heart disease and peripheral arterial disease. A lower percentage of claudicants had the Pl(A2) allele (8.3% vs. 15.2%, p=0.025). After adjustment for age and sex, the risk of IC associated with the Pl(A2) was half that of the homozygous Pl(A1) genotype (OR 0.49, 95% CI 0.25, 0.88; p<==0.05). Adjustment for lifetime smoking and fibrinogen levels increased the odds slightly to nonsignificance. CONCLUSIONS: The Pl(A2) genotype was associated with a decreased risk of developing IC. There was no significant relationship between fibrinogen T/G(+1689) genotype and ischaemic and peripheral heart disease in this older population.

Aged↗
PubMed2003

Changes in ankle brachial index in symptomatic and asymptomatic subjects in the general population.

OBJECTIVE: To determine changes over time in the ankle brachial index (ABI) among subjects with and without intermittent claudication in the general population. DESIGN OF STUDY: Population cohort study. SETTING: General population in Edinburgh, Scotland. SUBJECTS: A total of 1592 men and women aged 55 to 74 years selected at random from age-sex registers of 11 general practices and followed up over 12 years. Main outcome measures Changes in ABI for each leg recorded at baseline in 1988 and at subsequent 5-year and 12-year clinical examinations. RESULTS: Overall, 695 subjects (348 men and 347 women) had valid ABI measurements on both legs at all three examinations. At baseline, the ABI was on average.03 higher in the right leg than the left (P < or =.001). Men had a mean ABI that was.07 higher than women (P < or =.001). Mean ABI in the worse leg showed little change over 12 years in both men and women. However, in the whole population, the ABI in the better leg showed a significant drop, 1.15 to 1.08 (P < or =.001). A total of 179 cases of intermittent claudication were identified during the 12-year follow-up. At baseline, ABI in the worse leg of the claudicants was significantly lower than in healthy subjects (.99 vs 1.08; P < or =.01). In claudicants, mean ABI in the worse leg fell by.04 over 5 years (P < or =.05) and in the better leg showed a highly significant drop of.09 (P < or =.001) to levels similar to those of the worse leg. CONCLUSIONS: The mean ABI in the worse leg of study subjects showed little progression over 12 years. Individuals with intermittent claudication experienced a greater decline in both legs compared with those without claudication. Deterioration occurred more rapidly in the limb with a higher ABI at baseline, which possibly indicates a systemic tendency to atherosclerosis.

Aged↗
PubMed2003

Lifestyle factors and the risk of varicose veins: Edinburgh Vein Study.

The objective of this study was to determine the inter-relationships between a range of lifestyle factors and risk of varicose veins to identify which factors may be implicated in the etiology. An age-stratified random sample of 1566 subjects (699 men and 867 women) aged 18 to 64 years was selected from 12 general practices throughout Edinburgh. A detailed self-administered questionnaire was completed, and a comprehensive physical examination determined the presence and severity of varicose veins. The slightly higher age-adjusted prevalence of varicose veins in men than in women (39.7% versus 32.2%) was not explained by adjustment for an extensive range of lifestyle risk factors (male odds ratio [OR] 2.11, 95% confidence interval [CI] 1.51-2.96). In both sexes, increasing height showed a significant relationship with varicose veins (male OR 1.50, 95% CI 1.18-1.93 and female OR 1.26, 95% CI 1.01-1.58). Among women, body mass index was associated with an increased risk of varicose veins (OR 1.26, 95% CI 1.02-1.54). The current study casts doubt as to whether varicose veins occur predominantly in women. In addition, no consistent relationship with any lifestyle factor was shown. Self-reported evidence suggested a familial susceptibility, thereby warranting future genetic studies.

Adolescent↗
PubMed2003

A prognostic index to predict long-term mortality in patients with mild to moderate chronic heart failure stabilised on angiotensin converting enzyme inhibitors.

BACKGROUND: Mortality in patients with mild to moderate chronic heart failure remains high. At present there is no easy way of identifying patients within this population at increased risk of death in the medium to long term. AIMS: To develop a prognostic index to identify outpatients with mild to moderate chronic heart failure at increased risk of death. METHODS AND RESULTS: Five hundred and fifty-three outpatients mean (S.D.) age 63(+/-10) years with symptoms of chronic heart failure (mean New York Heart Association functional class, 2.3(+/-0.5)), were recruited between December 1993 and April 1995. By April 2000, 201 patients had died. Using data from non-invasive measurements of cardiac size, electrical and autonomic function, renal function and plasma biochemistry we identified eight independent predictors of mortality (all P<0.01). To develop a prognostic index, predictors were dichotomised by group median and awarded 0 or 1 point accordingly. Serum sodium </=140 mmol/l (1 point), creatinine >/=111 micromol/l (1 point), cardiothoracic ratio >/=0.52 (1 point), SDNN </=112 ms (1 point), maximum corrected QT interval >/=487 ms (1 point), QRS dispersion>/=42.7 ms (1 point), the presence of non-sustained ventricular tachycardia (1 point) and voltage criteria for left ventricular hypertrophy on 12-lead ECG (1 point). We calculated risk scores for patients by adding the points of each independent risk factor. In the low-risk group (0-3 points) mortality at 5 years was 20% and in the high-risk group (4-8 points) 53%. The area under the receiver-operator characteristic curve using dichotomised variables was 0.74 and for continuous model 0.78. CONCLUSIONS: Our prognostic index which uses eight non-invasive measurements and a straightforward additive points system, has good discrimination and stratifies outpatients with chronic heart failure into high and low risk. This index may be useful in clinical care and risk stratification.

Adolescent↗
PubMed2003

Cardiac size, autonomic function, and 5-year follow-up of chronic heart failure patients with severe prolongation of ventricular activation.

BACKGROUND: Chronic heart failure is characterized by left ventricular dilation and abnormalities of cardiac autonomic function. Up to 20% of patients with chronic heart failure have QRS prolongation, which can lead to asynchronous left ventricular contraction. We tested the hypotheses that in patients with chronic heart failure, QRS > 150 ms is a risk factor for additional abnormalities of ventricular morphology, heart rate variability, and increased mortality. METHODS AND RESULTS: In 184 patients with left ventricular ejection fraction < 35%, QRS duration was > 150 ms in 53, and </= 150 ms in 131. We evaluated patients with baseline chest radiographs, echocardiograms, and Holter recordings. Patients with QRS duration above and below 150 ms were similar in age, sex, functional class, renal function, serum sodium, and ejection fraction. In patients with QRS > 150 ms, left ventricular end-diastolic and end-systolic diameters were greater than patients with QRS duration </=150 ms (P <.01). Patients with QRS > 150 ms had less low frequency R-R interval spectral power (P <.04). At 5 years 60% of patients with QRS > 150 ms had died compared with 35% of patients with QRS </=150 ms (P <.001). This increase in mortality was predominantly the result of an increase in progressive heart failure. CONCLUSIONS: Chronic heart failure patients with QRS duration > 150 ms have exaggerated disturbance of cardiac autonomic function, and left ventricular remodeling and significantly higher mortality than patients with QRS duration </= 150 ms.

Autonomic Nervous System↗
PubMed2003

The relationship between aortic wall distensibility and rupture of infrarenal abdominal aortic aneurysm.

OBJECTIVE: A more accurate means of prediction of abdominal aortic aneurysm (AAA) rupture would improve the clinical and cost effectiveness of prophylactic repair. The purpose of this study was to determine whether AAA wall distensibility can be used to predict time to rupture independently of other recognized risk factors. METHODS: A prospective, six-center study of 210 patients with AAA in whom blood pressure (BP), maximum AAA diameter (Dmax), and AAA distensibility (pressure strain elastic modulus [Ep] and stiffness [beta]) were measured at 6 months with an ultrasound scan-based echo-tracking technique. A stepwise, time-dependent, Cox proportional hazards model was used to determine the effect on time to rupture of age, gender, BP, Dmax, BP, Ep, beta, and change in Dmax, Ep, and beta adjusted for time between follow-up visits. RESULTS: Median (interquartile range) AAA diameter was 48 mm (41 to 54 mm), median age was 72 years (68 to 77 years), and median follow-up period was 19 months (9 to 30 months). In the Cox model, female gender (hazards ratio [HR], 2.78; 95% CI, 1.23 to 6.28; P =.014), larger Dmax (HR, 1.36 for 10% increase in Dmax; 95% CI, 1.12 to 1.66; P =.002), higher diastolic BP (HR, 1.13 for 10% increase in BP; 95% CI, 1.13 to 1.92; P =.004), and a decrease in Ep (increase in distensibility) over time (HR, 1.38 for 10% decrease in Ep over 6 months; 95% CI, 1.08 to 1.78; P =.010) significantly reduced the time to rupture (had a shorter time to rupture). CONCLUSION: Women have a shorter time to AAA rupture. The measurement of AAA distensibility, diastolic BP, and diameter may provide a more accurate assessment of rupture risk than diameter alone.

Aged↗
PubMed2003

Multisensory integration in speed estimation during self-motion.

This study assessed the relative contributions of visual and proprioceptive/motor information during self-motion in a virtual environment using a speed discrimination task. Subjects wore a head-mounted display and rode a stationary bicycle along a straight path in an empty, seemingly infinite hallway with random surface texture. For each trial, subjects were required to pedal the bicycle along two paths at two different speeds (a standard speed and a comparison speed) and subsequently report whether the second speed travelled was faster than the first. The standard speed remained the same while the comparison speed was varied between trials according to the method of constant stimuli. When visual and proprioceptive/motor cues were provided separately or in combination, the speed discrimination thresholds were comparable, suggesting that either cue alone is sufficient. When the relation between visual and proprioceptive information was made inconsistent by varying optic flow gain, the resulting psychometric functions shifted along the horizontal axis (pedalling speed). The degree of separation between these functions indicated that both optic flow and proprioceptive cues contributed to speed estimation, with proprioceptive cues being dominant. These results suggest an important role for proprioceptive information in speed estimation during self-motion.

Adult↗
PubMed2003

Homocysteine concentrations lowered following dietary intervention in an aboriginal community.

Low circulating folate concentrations lead to elevations of plasma homocysteine. Even mild elevations of plasma homocysteine are associated with significantly increased risk of cardiovascular disease (CVD). Available evidence suggests that poor nutrition contributes to excessive premature CVD mortality in Australian Aboriginal people. The aim of the present study was to examine the effect of a nutrition intervention program conducted in an Aboriginal community on plasma homocysteine concentrations in a community-based cohort. From 1989, a health and nutrition project was developed, implemented and evaluated with the people of a remote Aboriginal community. Plasma homocysteine concentrations were measured in a community-based cohort of 14 men and 21 women screened at baseline, 6 months and 12 months. From baseline to 6 months there was a fall in mean plasma homocysteine of over 2|mol/L (P = 0.006) but no further change thereafter (P = 0.433). These changes were associated with a significant increase in red cell folate concentration from baseline to 6 months (P < 0.001) and a further increase from 6 to 12 months (P < 0.001). In multiple regression analysis, change in homocysteine concentration from baseline to 6 months was predicted by change in red cell folate (P = 0.002) and baseline homocysteine (P < 0.001) concentrations, but not by age, gender or baseline red cell folate concentration. We conclude that modest improvements in dietary quality among populations with poor nutrition (and limited disposable income) can lead to reductions in CVD risk.

Adult↗
PubMed2002

Predicting death due to progressive heart failure in patients with mild-to-moderate chronic heart failure.

OBJECTIVES: The aim of this study was to explore the value of noninvasive predictors of death/mode of death in ambulant outpatients with chronic heart failure (HF). BACKGROUND: Mortality in chronic HF remains high, with a significant number of patients dying of progressive disease. Identification of these patients is important. METHODS: We recruited 553 ambulant outpatients age 63 +/- 10 years with symptoms of chronic HF (New York Heart Association functional class, 2.3 +/- 0.5) and objective evidence of left ventricular dysfunction (ejection fraction <45%, cardiothoracic ratio >0.55, or pulmonary edema on chest radiograph). After 2,365 patient-years of follow-up, 201 patients had died, with 76 events due to progressive HF. RESULTS: Independent predictors of all-cause mortality assessed with the Cox proportional hazards model were as follows: a low standard deviation of all normal-to-normal RR intervals (SDNN); lower serum sodium and higher creatinine levels; higher cardiothoracic ratio; nonsustained ventricular tachycardia; higher left ventricular end-systolic diameter; left ventricular hypertrophy; and increasing age. Independent predictors of death specific to progressive HF were SDNN, serum sodium and creatinine levels. The hazard ratio of progressive HF death for a 10% decrease in SDNN was 1.06 (95% confidence interval [CI], 1.01 to 1.12); for a 2 mmol/l decrease in serum sodium, 1.22 (95% CI, 1.08 to 1.38); and for a 10 micromol/l increase in serum creatinine, 1.14 (95% CI, 1.09 to 1.19) (all p < 0.01). CONCLUSIONS: In ambulant outpatients with chronic HF, low serum sodium and SDNN and high serum creatinine identify patients at increased risk of death due to progressive HF.

Adolescent↗
PubMed2002

Chronic venous insufficiency: clinical and duplex correlations. The Edinburgh Vein Study of venous disorders in the general population.

OBJECTIVE: The objective of this study was to determine the prevalence of chronic venous insufficiency (CVI) in the general population and to correlate its clinical features with sonographically proven venous reflux. DESIGN OF STUDY: The study design was a cross-sectional survey of the general population. SUBJECTS AND METHOD: Ambulatory men and women, aged 18-64 years, were selected randomly from 12 general practices. Subjects were examined for CVI. Eight segments of the deep and superficial veins were assessed for reflux by means of duplex scanning. RESULTS: A total of 1566 subjects were screened (867 women, mean age 44.8 years; 699 men, mean age 45.8 years) of whom 124 were diagnosed as having CVI: 95, grade 1; 19, grade 2; and 10, grade 3. The age-adjusted prevalence for the whole population was 9.4% in men and 6.6% in women. Prevalence of CVI correlated closely with age and sex, being 21.2% in men >50 years and 12.0% in women >50 years. Heaviness and tension, and a feeling of swelling, aching, and itching, were significantly associated with worsening grade of CVI. CVI was significantly associated with reflux in all deep and superficial segments. The frequency of reflux in both superficial and deep segments increased with the clinical severity of disease. In 30.8% of subjects with CVI in the left leg, reflux was limited to the superficial system. CONCLUSIONS: The prevalence of CVI rises steeply with age. There is a strong correlation between venous symptoms and the presence and severity of CVI. CVI is associated in approximately one third of the subjects with incompetence limited to the superficial system and in these a good therapeutic outcome could be expected from surgery to the superficial veins. The severity of clinical features, including Basle CVI grade 1, correlates significantly with prevalence of valvular reflux in the deep and superficial systems. If leg ulcers are to be prevented by timely intervention, a better understanding of the natural history of the association between presenting features and disordered hemodynamics is required.

Adolescent↗
PubMed2002

Patient, operative, and surgeon factors that influence the effect of superficial venous surgery on disease-specific quality of life.

BACKGROUND AND OBJECTIVE: Superficial venous surgery for CEAP 2 disease leads to an improvement in disease-specific quality of life (QoL) in the short term. However, which factors influence the magnitude of this improvement, how surgery affects QoL in patients with CEAP 4 to 6 disease, and whether this improvement is durable are not known. The objective of this study was to identify patient, operative, and surgeon factors that might influence the change in disease-specific QoL in the 2 years after superficial venous surgery. METHODS: This prospective study was comprised of 203 unselected, consecutive patients with CEAP 2 to 6 disease who underwent saphenous with or without subfascial endoscopic perforator surgery and who completed the Aberdeen Varicose Vein Symptoms Severity Score (AVVSSS) before surgery and at 4 weeks, 6 months, and 2 years after surgery. Univariate and multivariate analyses were performed. RESULTS: At baseline, recurrent and ulcer (CEAP 5 and 6) diseases were associated with a higher (worse) AVVSSS. Surgery was associated with a significant improvement in median (interquartile range [IQR]) AVVSSS: baseline, 17.8 (11.8 to 27.2); 4 weeks, 13.8 (7.9 to 21.3); 6 months, 9.6 (4.2 to 15.8); and 2 years, 8.1 (4.0 to 14.7). One hundred seventy-five patients (86%) at 6 months and 177 patients (87%) at 2 years reported an improvement in AVVSSS. Postoperative AVVSSS at both 6 months and 2 years was most significantly influenced by preoperative score (P <.0001). After adjustment for baseline AVVSSS, the following factors were identified in multivariate analysis as having a significant and independent positive (+) or negative (-) impact on AVVSSS: at 6 months, (-) recurrent disease (P =.009), (-) CEAP 4 disease (P =.026); and at 2 years, (+) long saphenous surgery (P =.02), (-) CEAP 5 disease (P =.030). CONCLUSION: In this unselected series, saphenous surgery with or without subfascial endoscopic perforator surgery led to an improvement in disease-specific QoL in 87% of patients out to 2 years. Although univariate analysis results suggested that many baseline factors might be associated with outcome, multivariate analysis results suggested that only surgery for recurrent disease and for CEAP 4/5 disease remained as significant negative, and only long saphenous surgery as significant positive, independent prognostic factors. These data provide evidence of the medium-term clinical effectiveness of venous surgery across the full spectrum of CEAP clinical grades, show the importance of multivariate analysis, and reemphasize the importance of minimization of recurrence.

Female↗
PubMed2002

Food availability, cost disparity and improvement in relation to accessibility and remoteness in Queensland.

This study is the first to describe disparity and change in the food supply between metropolitan, rural and remote stores by Accessibility/Remoteness Index of Australia (ARIA) category. A total of 92 stores (97% response rate) within five aggregate ARIA categories participated throughout Queensland in 2000. There was a strong association between ARIA category and the cost of the basket of basic foods, with prices being significantly higher (20% and 31% respectively) in the 'remote' and 'very remote' categories than in the 'highly accessible' category. The association with ARIA was less marked for fruit and vegetables than for other food groups, but not for tobacco and take-away food items. Basic food items were less available in the more remote stores. Over the past two years, relative improvements in food prices have been seen in stores in the 'very remote' category, with observed increases less than the consumer price index (CPI) for food. Some factors which may have contributed to this improvement are discussed.

Choice Behavior↗
PubMedDate not supplied

Modified comet assay as a biomarker of sodium dichromate-induced oxidative DNA damage: optimization and reproducibility.

Hexavalent chromium (Cr[VI]) is a genotoxic carcinogen that has been associated with an increased risk of nasal and respiratory tract cancers following occupational exposure. Although the precise mechanism(s) remain to be elucidated, there is evidence for a role of oxidative DNA damage in the genotoxicity of Cr(VI). In the current study, human white blood cells were treated in vitro with non-cytotoxic concentrations of sodium dichromate (1-100 microM) for 1 h. Analysis by immunocytochemistry indicated the presence of elevated levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine at concentrations of sodium dichromate greater than 10 microM. In contrast, the lowest concentration of dichromate that resulted in a statistically significant increase in levels of formamidopyrimidine DNA glycosylase (FPG)-dependent DNA strand breaks was 100 nM (p<0.05). In addition, levels of both control and dichromate-induced FPG-dependent strand breaks from blood samples taken from the same individuals over 10 months proved remarkably reproducible in the individuals studied. The coefficients of variation over three different times of the year in control and dichromate-induced oxidative DNA damage for the four individuals were 54, 1, 37 and 4, and 45, 6, 21 and 18%, respectively. In summary, these results indicate that physiologically relevant, nanomolar concentrations of sodium dichromate cause DNA base oxidation in human white blood cells in vitro as assessed by the FPG-modified comet assay. Furthermore, comet assay data from an individual are reproducible over an extended period. This consistency is sufficient to suggest that the modified comet assay might prove to be a useful and sensitive biomonitoring tool for individuals occupationally exposed to hexavalent chromium.

Biomarkers↗