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Purpose: To compare exercise capacity and cardiovascular response to exercise in elderly individuals with coronary artery disease (CAD) who attend ongoing community-based maintenance cardiac rehabilitation (CR) versus age- and gender-matched healthy "very active" (HVA; ≥ 2000 kcal/week) and healthy "less active" (HLA; <2000 kcal/week) individuals., Method: Sixty-three participants (age: 72.3 ± 5.1 years; 62% men; n = 21 per group) completed the following assessments: (1) symptom-limited graded exercise test with expired gas analysis and bioimpedance assessment of cardiovascular function during exercise; (2) walking tests; (3) physical function; (4) anthropometry and (5) 12-month physical activity recall., Results: The CR group achieved 98% (range: 73-154%) of age- and gender-predicted peak oxygen consumption for healthy individuals. Peak oxygen consumption was lower in CR compared to HVA but not HLA group (VO2peak: CR: 19.0 ± 4.5, HVA: 23.7 ± 2.9, HLA: 20.7 ± 4.7 ml ·kg(-1)ċmin(-1), p = 0.001 versus HVA; p = 0.390 versus HLA). Peak heart rate was lower in CR compared to both HVA and HLA. Walking test results and cardiovascular and physical function were not different between the groups., Conclusions: Elderly individuals with CAD participating in maintenance CR have similar exercise capacity and cardiorespiratory response to exercise compared to their age- and gender-matched less active healthy peers. The findings support referral of elderly patients to community-based CR., Implications for Rehabilitation: Fitness benefits of long-term maintenance cardiac rehabilitation (CR) programs remain unknown. Elderly individuals with coronary artery disease participating in maintenance CR have exercise capacity and cardiorespiratory response to exercise similar to their less active healthy peers. Maintenance CR may play an important role prolonging independent living in elderly individuals.

Background: Cardiac rehabilitation (CR) graduates are encouraged to attend maintenance programs to promote long-term physical activity and preserve gains in function. This study describes the characteristics, attendance and physical function of community-based maintenance CR participants, compared to primary prevention participants., Methods: In this cross-sectional study, participants from two programs in New Zealand completed an interview, anthropometry, functional assessments (walking tests, chair stand test, handgrip strength), a 12-month physical activity recall, and a cardiopulmonary exercise test (subsample only). Attendance was ascertained from club records., Results: Participants (n=101, 55.4% Secondary Prevention) attended 37.4±27.9% of sessions annually. Participants were predominately New Zealand-European (93.5%), retired (80.2%), married (68.3%) elderly individuals, with musculoskeletal problems (60.0%), who lived proximate to the clubs. In Secondary but not Primary Prevention participants, first-year attendance was strongly correlated with attendance in subsequent years (p<0.001). In all participants, greater attendance in the previous 12 months was significantly associated with lower waist circumference, and greater shuttle walk test duration, chair stands and balance (p<.05). Session attendance was positively correlated to peak oxygen consumption (p=0.041) in Secondary Prevention participants only., Conclusion: Participation in community-based CR maintenance programs is associated with health benefits but these programs are not accessed by a diversity of patients., (Copyright © 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Purpose: Compared with symptom-limited cardiopulmonary exercise test (CPET), timed walking tests are cheaper, well-tolerated and simpler alternative for assessing exercise capacity in coronary artery disease (CAD) patients. We developed multivariate models for predicting peak oxygen consumption (VO2peak) from 6-minute walk test (6MWT) distance and peak shuttle walk speed for elderly stable CAD patients., Methods: Fifty-eight CAD patients (72 SD 6 years, 66% men) completed: (1) CPET with expired gas analysis on a cycle ergometer, (2) incremental 10-meter shuttle walk test, (3) two 6MWTs, (4) anthropometric assessment and (5) 30-second chair stands. Linear regression models were developed for estimating VO2peak from 6MWT distance and peak shuttle walk speed as well as demographic, anthropometric and functional variables., Results: Measured VO2peak was significantly related to 6MWT distance (r = 0.719, p < 0.001) and peak shuttle walk speed (r = 0.717, p < 0.001). The addition of demographic (age, gender), anthropometric (height, weight, body mass index, body composition) and functional characteristics (30-second chair stands) increased the accuracy of predicting VO2peak from both 6MWT distance and peak shuttle walk speed (from 51% to 73% of VO2peak variance explained)., Conclusions: Addition of demographic, anthropometric and functional characteristics improves the accuracy of VO2peak estimate based on walking tests in elderly individuals with stable CAD. Implications for Rehabilitation Timed walking tests are cheaper, well-tolerated and simpler alternative for assessing exercise capacity in cardiac patients. Walking tests could be used to assess individual's functional capacity and response to therapeutic interventions when symptom-limited cardiopulmonary exercise testing is not practical or not necessary for clinical reasons. Addition of demographic, anthropometric and functional characteristics improves the accuracy of peak oxygen consumption estimate based on 6-minute walk test distance and peak shuttle walk speed in elderly patients with coronary artery disease.

Objective: To examine long-term changes in physical function and body composition in coronary artery disease (CAD) patients participating in ongoing community-based cardiac rehabilitation (CR)., Design: Thirty-four individuals (69.7 ± 8.2 years; 79% men) participated in this longitudinal observational study. Baseline and follow-up assessments included incremental shuttle walk, short physical performance battery, handgrip strength, chair stands, body composition, last year physical activity, and CR attendance., Results: Participants attended 38.5 ± 30.3% sessions during 1.6 ± 0.2 year followup. A significant increase in 30-second chair stands (17.0 ± 4.7 to 19.6 ± 6.4, P < 0.001), body weight (75.8 ± 11.1 to 77.2 ± 12.1 kg, P = 0.001), and body fat (27.0 ± 9.5 to 29.1 ± 9.6%, P < 0.001) and a decline in handgrip strength (36.4 ± 9.4 to 33.0 ± 10.6 kg·f, P < 0.001) and muscle mass (40.8 ± 5.6 to 39.3 ± 5.8%, P < 0.001) were observed during followup. There was no significant change in shuttle walk duration. CR attendance was not correlated to observed changes., Conclusions: Elderly CAD patients participating in a maintenance CR program improve lower-body muscle strength but experience a decline in handgrip strength and unfavourable changes in body composition, irrespective of CR attendance.

There has never been a locally transmitted outbreak of mosquito-borne disease in New Zealand, but the risk of an outbreak occurring is increasing with on-going interceptions of exotic mosquito vectors across its border, increasing traffic of goods and passengers, higher numbers of viremic travelers arriving, and local, regional, and global environmental change. The risk posed to New Zealand by chikungunya virus is potentially high because of the transmissibility of this virus in subtropical climates, compounded by a population that is predominantly immunologically naive to exotic arboviruses. However, risk reduction in New Zealand should not be considered in isolation but must be viewed within a wider South Pacific context. In this report, we discuss the potential threat posed by chikungunya to the region, focusing in particular on New Zealand, and re-emphasizing the need for a South Pacific-wide approach towards mosquito-borne disease prevention.

Some patients with coronary artery disease experience continued progression of one or more coronary lesions despite treatment with drugs that inhibit 3-hydroxy-3-methylglutaryl coenzyme A reductase activity and markedly lower plasma cholesterol levels. We examined relationships between the progression of coronary artery lesions and plasma lipoproteins, in particular intermediate density lipoprotein (IDL) and its composition, in 38 patients with coronary artery disease who had been treated with simvastatin for 2 years. Patients were given lipid-lowering dietary advice; 3 months later they were started on simvastatin therapy (10 mg/d) for 1 month, and after review of their plasma cholesterol levels, the dose was increased to 20 mg/d and later to 40 mg/d if the target level of plasma cholesterol had not been attained. Progression of lesions was determined by serial quantitative coronary angiography (variability of 5.5%) and was defined as an increase in percent diameter stenosis (%S)> or =10%; regression was defined as a decrease in %S > or =10%. The proportions of cholesteryl esters (CEs) and free cholesterol decreased significantly (P<.001), and proportions of protein and triglycerides increased significantly (P<.001) in IDL during simvastatin therapy. The CE content of IDL decreased significantly (-7.2 weight [wt]%, n=20, P<.001) in nonprogressors (patients who did not show progression of any lesions) and did not change significantly (-1.8 wt%, n=14, P=.36) in progressors (patients who showed progression of one or more lesions without regression of any lesion). This decrease in IDL CE content in nonprogressors was significantly (P=.01) different compared with the corresponding change in patients classified as progressors. Mean plasma cholesterol concentration tended to increase in progressors (0.47 mmol/L) and tended to decrease in nonprogressors (-0.39 mmol/L) during the initial 3-month diet period, and these changes were significantly different (P=.02). Furthermore, this change in plasma cholesterol level during the initial diet period was correlated significantly with the change in IDL CE content during the entire study (r=.348, n=38, P=.03). These data suggest that IDL CE content may be a determinant of progression of coronary lesions and may be influenced by compliance with or metabolic response to lipid-lowering dietary advice in patients with coronary artery disease during simvastatin treatment.

Objective: The aim of the study was to compare red blood cell (RBC) fatty acid composition, plasma lipids and lipoproteins and dietary intake between urban and rural Melanesian Fijians., Design: A cross-sectional study was performed in a random subsample (n = 154) from a total survey population of 589 subjects., Setting: Melanesian Fijians living in the relatively urban settlement of Nabua, Suva and On the remote island of Qamea (rural) were studied., Results: The proportions of myristic acid (1.4% versus 0.3%, P < 0.001) and arachidonic acid (10.1% versus 11.4%, P < 0.01) were significantly higher and proportions of oleic acid (14.4% versus 13.2%, P < 0.05) and linoleic acid (11.9% versus 8.1%, P < 0.001) were significantly lower in RBC from rural compared with urban men, and a similar pattern was seen in women. Plasma cholesterol levels were significantly (P < 0.05) higher in the rural subjects. Urban/rural differences in plasma cholesterol levels were not significant when the proportion of RBC myristate was taken into account., Conclusions: The results suggest that consumption of myristic acid from coconut fat is greater and the intake of linoleic acid is less in Fijians living on a remote island and may contribute to their higher plasma cholesterol levels compared with their urban counterparts.

Plasma cholesteryl ester transfer protein (CETP) activity and distribution of red blood cell (RBC) cholesterol among plasma lipoproteins during incubation of blood were determined in 14 distance runners and 10 sedentary men. Mean plasma CETP activity was similar in the runners (31% 10 microliters-1 18 h-1) and the sedentary men (32% 10 microliters-1 18 h-1). There was significantly (P < 0.05) greater accumulation of cell cholesterol in the HDL fraction (runners: 0.33 mmol l-1; sedentary men: 0.23 mmol l-1) which comprised a significantly (P < 0.05) larger proportion of the total amount of cell cholesterol lost to plasma (runners: 89%; sedentary men: 64%) in incubated blood from the runners. The results of this study suggest that in distance runners, high HDL concentrations are not accompanied by reduced plasma CETP levels but in conjunction with low triglyceride-rich lipoprotein levels in plasma, may promote preferential distribution of cell cholesterol into the 'antiatherogenic' HDL fraction.

Blood pressures were measured as part of a health check in a randomly selected sample of the New Zealand population. One thousand, four hundred and ten men and 1605 women over 15 years were studied. Measurements were made by trained observers using the Hawksley Random Zero instrument. Systolic and diastolic pressures increased with age in men and women. There were 29% of men and 24% of women over the age of 45 with pressures over 160/95 mmHg of whom 24% of men and 33% of women were on treatment for hypertension. Of all subjects 9% of men and 12% of women were on treatment for hypertension. Systolic and diastolic pressures correlated significantly with body mass index, waist/hip ratio and skinfold measurements in men and women. The most significant correlation was with the body mass index. No regional or urban/rural differences were seen in systolic or diastolic pressures. A history of hypertension in the fathers of respondents related to blood pressures in the highest tertile of diastolic blood pressures in males, and systolic pressure of females. The association was not seen between mothers of respondents in respect of diastolic pressure.

Faecal steroid excretion, including betasitosterol excretion, whole-body cholesterol synthesis, plasma lipids, and lipoprotein concentrations and habitual diet, were determined in 14 male distance runners and 14 sedentary men. The proportion of cholesterol-derived steroids excreted as bile acids, and the quantity of betasitosterol excreted in the faeces were significantly (P less than 0.05) higher in the runners compared with the sedentary men. Faecal betasitosterol excretion and the proportion of cholesterol-derived steroids excreted as bile acids were correlated significantly in the distance runners and the sedentary men (r = 0.774, n = 28, P less than 0.001). These results suggest that greater dietary intake of plant sterols may contribute to the higher proportion of cholesterol-derived steroids excreted as bile acids in distance runners.

Fecal bile acid concentration, fecal characteristics, bowel habits and habitual food intake were measured in male distance runners (n = 14) and sedentary men (n = 14). Fecal bile acid concentration was significantly (p less than 0.05) lower and stool weight, frequency of defecation and daily intake of fibre, carbohydrate, and protein were significantly (p less than 0.01) higher in the runners. After adjustment for differences in dietary fibre intake, fecal bile acid concentration was no longer significantly different between the distance runners and the sedentary men, but frequency of defecation remained significantly (p less than 0.05) higher in the runners. This study has identified lower fecal bile acid concentration in distance runners, which was probably due mainly to dilution of colon contents by higher consumption of dietary fibre. These findings may be relevant to the reduced incidence of colon cancer in physically active subjects.

Objective: To assess the efficacy of simvastatin in a large patient cohort., Design: In an open multicentre study, after a four week placebo phase, patients were treated with simvastatin for 24 weeks; a subgroup continued therapy for a further 24 weeks. Efficacy of simvastatin (a) with prolonged use over three years, and (b) in combination with bezafibrate was assessed in an open single site study., Setting: Lipid or cardiology specialist hospital outpatient clinics., Patients: For the open multicentre study, 228 patients with primary hypercholesterolaemia (total cholesterol level greater than 6.5 mmol/L) were recruited, of whom 224 met entry criteria and completed the study. Forty-seven of these patients continued therapy for one year. In the open single site study, 22 patients (with low density lipoprotein [LDL] cholesterol levels greater than 4.3 mmol/L) participated in studies of long term use (n = 9) or of combined therapy (n = 13)., Intervention: Therapy in the open multicentre study began with 10 mg of simvastatin per day, doubling to 20 mg after six weeks and then 40 mg after 12 weeks of therapy if total cholesterol levels persisted above 5.2 mmol/L. In the study of long term use, simvastatin (40 mg daily) was taken continuously over three years. In the study of combination therapy, bezafibrate (600 mg daily) was taken in addition to simvastatin (40 mg daily) for 10 months., Main Outcome Measures: Plasma lipid and lipoprotein concentrations., Results: In the multicentre study, total plasma cholesterol levels were reduced by 32.8% from 9.11 +/- 1.84 (in mmol/L, mean +/- SD) to 6.12 +/- 1.25 (P less than 0.001), and LDL cholesterol levels by 41.4% from 6.90 +/- 1.92 to 4.04 +/- 0.31 (P less than 0.001). The effect of therapy was sustained in those patients continuing therapy to 48 weeks. The study of long term use found no significant attenuation of effect over three years of monotherapy. Combined simvastatin/bezafibrate therapy reduced the LDL cholesterol concentration by a further 19.9% (P less than 0.001) from levels achieved on simvastatin alone., Conclusions: Simvastatin is an effective, well tolerated lipid lowering drug, without significant attenuation of effect with prolonged use. Simvastatin plus bezafibrate appears to be a potentially useful drug combination.

Objects: to compare men and women over the age of 35 years in Dunedin (New Zealand) and Uppsala (Sweden) in respect of anthropometric values, dietary habits and certain coronary heart disease risk factors in view of known differences in coronary mortality between the two countries., Methods: one hundred and ninety-five Dunedin and 94 Uppsala residents were chosen randomly from the respective populations, in the former city by electoral roll, in the latter by use of unique personal number. Measurements of height, weight, waist/hip ratio, blood pressure, blood lipids were made and dietary and smoking habits assessed., Results: the Swedes were taller and leaner than the New Zealanders. Blood pressure and smoking habits were not significantly different but total blood cholesterol levels were lower in Uppsala men and women. Blood triglycerides were higher in Dunedin women but high density lipoprotein cholesterol levels tended to be lower in men and women in Uppsala., Conclusions: it was found by analysis of variance that the blood lipid level differences between the two populations could be explained by body mass index. Correction of lipid values for the waist/hip ratio partly explained the higher cholesterol values in Dunedin but diet differences may also have been contributory. The differences in coronary mortality between the population of New Zealand and Sweden are compatible with the view that our blood cholesterol findings reflect the different levels of risk.

Plasma lathosterol concentration is taken to be an index of the rate of cholesterol synthesis and plasma concentrations of plant sterols just as campesterol and betasitosterol are taken to be indeces of cholesterol absorption efficiency. These noncholesterol sterols were measured in plasma from 14 male distance runners and 10 sedentary men. Plasma lathosterol concentration was 30% lower (P less than 0.02) and plasma betasitosterol concentration was 33% higher (P less than 0.02) in the runners compared to the sedentary men. Plasma concentrations of lathosterol and plant sterols were inversely and significantly (P less than 0.05) correlated in both the runners and the sedentary men. Plasma plant sterol concentrations were correlated positively and significantly (P less than 0.01) with plasma high density lipoprotein cholesterol (HDL-C) concentrations in the runners and sedentary men combined. These findings suggest that more efficient cholesterol absorption may lead to higher plasma plant sterol concentrations and may contribute to lower cholesterol synthesis rates, reduced concentrations of plasma lathosterol and higher plasma HDL-C concentration in distance runners.

In order to study the effects of eicosapentaenoic acid (Maxepa), Maxepa placebo and aspirin/dipyridamole combination on the clinical course and restenosis rate of atherosclerotic lesions after percutaneous transluminal coronary angioplasty 79 men and 29 women were randomly divided into three treatment groups and restudied angiographically within one year of the procedure. Angina recurred less in the Maxepa group than in the other groups, although not statistically so. Restenosis rate was significantly reduced in the Maxepa group (11%) compared to the placebo group (30%) but, while less, was not significantly lower than in the aspirin/dipyridamole group (17%). Maxepa treatment appears to reduce restenosis rate of coronary artery lesions after percutaneous transluminal coronary angioplasty and may be an acceptable and equally effective alternative therapy to aspirin/dipyridamole.

Blood pressures (BPs) were measured as part of a health check in a randomly selected sample of the New Zealand population in the Life in New Zealand survey. A total of 1,410 men and 1,605 women over 15 years of age were studied. Measurements were made by trained observers using the Hawksley random zero instrument. Systolic BP (SBP) and diastolic BP (DBP) increased with age in men and women. There were 29% of men and 24% of women over the age of 45 years with BPs over 160/95 mm Hg, of whom 24% of men and 33% of women indicated they were on treatment for hypertension. No regional or urban/rural differences were seen in either SBPs or DBPs. A history of hypertension in the fathers of respondents related to BPs in the highest tertile of SBPs in males, and SBPs in females. The association was not seen between mothers of respondents, except for DBP in women respondents.

The present study examined fasting serum insulin levels in relation to body composition and dietary intake during the initial 4 weeks of a 12-week physical training programme in 26 previously sedentary men. Fasting serum insulin concentrations decreased markedly during the first 4 weeks of training and remained at these reduced levels for the rest of the study. The early fall in serum insulin concentration was significantly correlated with the concomitant decrease in body fat, the increase in lean body weight and the age of the subjects. Body weight and reported dietary intake on the other hand, did not change significantly over this period. These results indicate that the decrease in fasting serum insulin in previously sedentary men with physical training is associated with the concomitant changes in body composition. Increased muscle tissue in particular may contribute to this training-induced decrease in serum insulin.

Lecithin:cholesterol acyltransferase (LCAT) activity, lipid concentration, lipoprotein lipid concentrations and cholesteryl ester linoleic acid proportion were determined in the plasma of 85 subjects randomly selected from a population during a health screen survey. Mean fractional LCAT rate was significantly higher in men than in women. Molar LCAT rate correlated with low density lipoprotein (LDL) cholesterol concentration in men and with nearly all lipoprotein lipid concentrations in women. Most of these relationships were dependent on plasma unesterified cholesterol (UC) concentration. Fractional LCAT rate was correlated only with HDL cholesterol concentration in women and this relation was dependent on the influence of obesity. An inverse relationship between plasma cholesteryl ester (PCE) linoleic acid proportion and molar LCAT rate in women was also explained by influences of obesity on the data. Both fractional and molar LCAT rates were positively correlated with obesity (Quetelet's Index and subscapular skinfold thickness) in women but not in men. This study showed the influence of sex on nearly all correlations involving LCAT activity in combined groups of men and women.

Indices of obesity, plasma lipids, and lipoprotein levels, plasma cholesteryl ester fatty acid composition, reported alcohol consumption and smoking habits were measured in 88 men and 87 women, ages over 15 years, randomly selected from the total respondents (1192) to a health survey. Most indices of obesity were related to plasma triglycerides and high-density lipoprotein levels in both sexes; to very low-density lipoprotein levels in men only; and to plasma cholesteryl ester fatty acid linoleic acid proportions in women only. The correlations with high-density lipoprotein cholesterol levels were dependent on very low-density lipoprotein triglyceride levels in men but not in women. Indices of obesity were significantly higher in nonsmoking women and reported alcohol consumption correlated with Quetelet's index (body mass index) in men. Smoking habits, but not alcohol consumption, influenced correlations between indices of obesity and plasma triglycerides and very low-density lipoprotein triglyceride levels in men. The present results showed several sex-related differences in relationships with indices of obesity. Lower very low-density lipoprotein levels, higher skinfold measurements, higher cholesteryl ester fatty acid linoleic acid proportions and lower alcohol intake in women than in men may be responsible. The data suggested that in women, altered diet composition may be linked with obesity.

To see if the magnitude of carbohydrate extraction by working skeletal muscle in man is inversely correlated with the arterial free fatty acid (FFA) concentration as in the heart, eighteen healthy men were studied during dynamic forearm work with and without nicotinic acid. The extraction or release of glucose, lactate and pyruvate was determined by the simultaneous sampling of blood from the brachial artery (a) and a deep vein (dv) of the active forearm. Nicotinic acid decreased the arterial FFA concentration from 498 +/- 53 to 134 +/- 12 mumol per litre plasma and this caused a decrease in calculated extraction of FFA. However, it did not affect the extraction of glucose, which was of a magnitude similar to one third of the oxidative metabolism in both situations. One of the possible reasons of this difference compared to the human heart muscle is that the exercising skeletal muscle may utilize stored substrate to a greater extent, which makes possible shifts in substrate utilized for oxidation without changes in substrate extraction. Another reason may be that FFA utilization covers a far smaller proportion of oxidative metabolism in skeletal than in heart muscle already before nicotinic acid.

Plasma lipoprotein lipid levels including IDL cholesterol concentration, physical fitness parameters, and anthropometric data were measured in 10 men with primary hypertriglyceridemia during a 12 week program of moderate physical training. Reduced pulse rate at submaximal workload and increased work performed on the treadmill indicated that the men had increased their physical fitness during the training period. Body weight (-4.9%) and total skinfold thickness (-15.6%) fell during the training program. A characteristic fall (-23%) in plasma triglyceride levels was seen over the first 8 weeks training. Plasma IDL cholesterol concentration fell (-18%) after 2 weeks training but then rose after 8 weeks to levels which tended to be higher than baseline values. Our data suggest that regular physical exercise is more likely to raise levels of the "proatherogenic" IDL than to lower them in hypertriglyceridemic patients.

Plasma cholesterol and triglycerides have been measured in 1202 residents of Milton, a rural town in New Zealand. Cholesterol and triglyceride concentrations in the serum lipoprotein classes of a random subgroup of the population are also reported. Mean plasma triglycerides and very low density lipoprotein (VLDL) cholesterol and triglyceride concentrations were higher for men, but mean high density lipoprotein (HDL) cholesterol concentration was higher in women. Urban-rural differences in plasma cholesterol are suggested since mean plasma cholesterol concentration in men reached a maximum in the 50-59 decade in the rural town (Milton) but the maximum for a nearby urban community was in the 40-49 decade. An evaluation of hyperlipidaemia by using arbitrary cut-off values for plasma cholesterol and triglyceride concentrations showed a prevalence of hypertriglyceridaemia in men, resulting in approximately three times as many men as women in some of the categories of hyperlipidaemia. Further, 26% of the 35-59 age group in the population had lipid risk factors for coronary heart disease.

1. Rats were fed for 8 weeks on one of five diets differing in the amount of fatty acids 18:1, 18:2 and 18:3. Lipolysis, in vitro, of epididymal fat from fed and fasted rats was measured both basally and in the presence of noradrenaline with and without prostaglandin E1. 2. Lipolysis was markedly influenced by the type of dietary fat. In particular, lipolysis in adipose tissue from rats given diets rich in the fatty acid 18:3 was higher than in the rats given diets containing 18:2. 3. Results showing the effects of fasting on adipose tissue lipolysis are also presented. 4. The results are discussed in relation to the known effects of unsaturated fats on hyperplasia and protein synthesis in adipose tissue and on the possible role of prostaglandins.

The effects of diets containing 5% of methyl-gamma-linolenate (delta 6,9,12) or 5% of methyl-alpha-linolenate (delta 9,12,15) on the fatty acid composition of lipids in rat plasma were studied. After 10 days the cholesterol esters and total phospholipids in the plasma of rats fed gamma-linolenate contained higher percentages of arachidonic acid than the corresponding lipid classes in the plasma of rats fed the alpha-isomer. A fairly high percentage of gamma-linolenic acid was incorporated into the cholesterol esters of rats fed methyl-gamma-linolenate.

The effect of linoleic acid on the induction of fatal ventricular fibrillation by intravenous CaCl2 (10%), was studied in rats fed for a month from weaning on a diet with either a high or low content of linoleic acid. Studies were performed in the basal state and after pretreatment with noradrenaline, which increased the sensitivity to CaCl2 equally in animals from both diet groups. Despite considerable differences in the linoleic acid levels in the plasma and myocardium, the two groups did not differ in the incidence of fatal ventricular fibrillation. Our conclusions concerning the effect of linoleic acid on cardiac arrhythmias, and sudden death in particular, are compared with those from other studies.

Multiple regression analysis of data on age, blood pressure, adiposity and blood lipids from a rural New Zealand population of over 1200 adults has been undertaken. The results show that rises in blood lipids over time in the population are independent of age and correlate significantly with adiposity. Thus plasma cholesterol and triglycerides correlate with adiposity (expressed as Quetelet's index or skinfold thickness) in men whereas significant correlation in women was only between adiposity and plasma triglycerides. Systolic and diastolic blood pressure in men was strongly correlated with their plasma triglycerides, but not cholesterol, when the effect of age and adiposity was removed. In women however only a weak correlation was observed between plasma triglycerides and systolic blood pressure. The significance of the findings is discussed.

Twelve members of a kindred were studied of whom six showed elevated low-density lipoprotein (LDL) cholesterol levels. Within the blood related group nine showed elevated high density lipoprotein (HDL) cholesterol levels and correspondingly elevated HDL lipoprotein apoprotein levels. The members with elevated LDL also therefore had elevated HDL. There was no family history of premature vascular disease in the kindred and the 74 year old member was clinically free of ischaemic vascular disease. It is considered that the coincidence of a familial tendency to high blood LDL and HDL was not associated with appearance of premature arterial disease in this kindred.

Anthropometric data, plasma lipoprotein lipid levels, and post-heparin lipoprotein lipase (PHLPL) activity were measured in nine patients with type III hyperlipoproteinemia (HLP) and two hypocholesterolemic subjects with the apo-E2/2 phenotype. Five type III HLP patients were treated with clofibrate. Log PHLPL activity was inversely correlated (r = -0.667, p less than 0.05) and age was positively correlated (r = 0.706, p less than 0.05) with cholesterol levels in the VLDL fraction of plasma from type III HLP patients. The correlation between log PHLPL and VLDL cholesterol levels remained significant when age was held constant in partial correlation analysis. Together age and log PHLPL activity accounted for 77% of individual variation in VLDL cholesterol levels in the type III patients. Clofibrate treatment raised PHLPL activity (+48%, p less than 0.05) and reduced the levels of VLDL cholesterol (-67%, P less than 0.05), VLDL triglycerides (-40%, P less than 0.02), and the ratio cholesterol/triglyceride in VLDL (-50%, P less than 0.05) in five type III HLP patients. Mean PHLPL activity was higher in the hypocholesterolemic subjects with the apo-E2/2 phenotype compared to the type III HLP patients. These results suggest that lipoprotein lipase activity and factors associated with age modulate the levels of abnormal and atherogenic remnant particles (beta-VLDL) in the VLDL plasma fraction of type III HLP patients.

Hyperchylomicronaemia and elevated very low density lipoproteins were found in relatively obese 47 year old identical twin brothers. Lipoprotein apoprotein studies showed the presence of apoprotein CII, the activator of lipoprotein lipase, and both men were homozygous E2/2. Studies on the ability of the brothers to clear triglyceride rich particles showed some impairment of post heparin lipase activity, and a slower clearance of infused fat emulsion. The values improved after weight loss. There was some evidence of impaired capacity of the patients' high density lipoprotein to activate post heparin lipoprotein lipase.

This study describes the efficacy of the drug simvastatin. It is likely to be the first HMG CoA reductase inhibitor in Australia and New Zealand available for the treatment of hyperlipidemia. Twenty-four patients, 12 men and 12 women with primary hypercholesterolemia were randomly allocated to treatment by cholestyramine (eight patients) or to simvastatin (16 patients) for a 12-week period. With simvastatin, total cholesterol levels decreased by 37.5% from a baseline mean of 10.33 mmol/L to 6.4 mmol/L after 12 weeks. Low density lipoprotein (LDL) cholesterol concentration decreased by 48.2% from 8.40 mmol/L to 4.39 mmol/L. These effects were better than observed for cholestyramine alone where cholesterol and LDL-cholesterol reductions were 24.9% and 33.1% respectively. Thirteen patients, however, did not achieve target LDL levels of 3.62 mmol/L, or below, and therefore were treated with a combination of cholestyramine and simvastatin, resulting in a decrease of total cholesterol and LDL-cholesterol by 45.5% and 53.5% of baseline values studied over an eight-week period. No major clinical side-effects were encountered. One patient appeared to have had a change in colour vision at the end of the study at 20 weeks, without loss of visual acuity.

This study has measured plasma lipoprotein lipid levels and the in vitro rate of cholesterol synthesis from [2(-14)C]acetate by mononuclear leukocytes in blood from normolipidemic subjects and two patients with Tangier disease. The rate of cholesterol synthesis in blood was related inversely to plasma levels of HDL cholesterol in the normolipidemic subjects. This relationship was mainly due to a similar correlation in the women. The rate of blood cholesterol synthesis was raised in a woman with Tangier disease, which is consistent with the above correlation, but not in a man with this disease. We suggest that this correlation reflects an association between plasma HDL cholesterol levels and whole-body sterol synthesis.

Thirty sedentary men aged 25-52 participated in a 4-month randomized and controlled study of the effects of exercise on plasma lipoproteins and faecal steroid excretion. After 4 months the aerobic training group showed a significant (P = 0.047) increase in physical work capacity (+38 watts) and a significant (P = 0.025) decrease in faecal total steroid excretion (-257 mg/day) compared to corresponding changes in the control group. The drop in faecal total steroid excretion in the men who trained was mainly due to a significant (P less than 0.05) fall in faecal neutral sterol excretion (-240 mg/day). Plasma lipoprotein lipid concentrations did not change significantly during the study although plasma levels of very low density lipoprotein (VLDL) cholesterol and low density lipoprotein (LDL) cholesterol tended to fall in the men who trained. In the aerobic training group individual changes in plasma LDL cholesterol levels were significantly correlated with decreases in faecal total steroid excretion (p = 0.615, P less than 0.05) and faecal neutral sterol excretion (p = 0.627, P less than 0.05). The results of this study show that regular exercise is associated with a drop in faecal neutral sterol excretion which, if sufficiently large, may be associated with a decrease in plasma LDL cholesterol concentration.