PubMed Health⌕ Search

Biomedical subjects

L Blizzard

Publications and source records attributed to L Blizzard.

31 records · Page 2Linked to original sources

Differences in HDL cholesterol concentrations in Japanese, American, and Australian children.

BACKGROUND: Mortality from coronary heart disease is relatively low in Japan compared with other developed countries and has remained low despite an increasing standard of living and an apparent increase in mean plasma cholesterol concentration in adults over the past three decades. Important differences in childhood plasma lipoprotein profile might contribute to some of the difference in coronary heart disease mortality seen between Japan and both Australia and North America. METHODS AND RESULTS: Plasma HDL cholesterol and total cholesterol were surveyed in representative populations of schoolchildren in Australia, Japan, and Bogalusa, La. The mean concentration of plasma HDL cholesterol (but not total cholesterol) was higher for Japanese schoolchildren than for Australian or US schoolchildren (P<.001). In addition, the difference in plasma HDL cholesterol between the ages of 8 to 10 years and 12 to 15 years was much greater for Australian (boys, 15.2%; girls, 2.6%) and US (boys, 9.1%; girls, 2.7%) children than for their Japanese counterparts (boys, 4.2%; girls, 1.9%). An examination of potential explanatory factors revealed little difference in body mass index between samples, higher physical activity levels for the Japanese compared with the Australians, and substantial differences in dietary intake between Japanese and Australian schoolchildren. CONCLUSIONS: The relatively high ratio of plasma HDL cholesterol to total cholesterol in Japanese schoolchildren and the relatively small negative difference of plasma HDL cholesterol with age may help to explain why the coronary heart disease mortality rate in Japan is low compared with that in other developed countries.

Adolescent↗

Association between blood pressure and dietary factors in the dietary and nutritional survey of British adults.

OBJECTIVES: To measure the associations among blood pressure, hypertension, and recorded dietary factors. METHODS: Data were analyzed from the computer file of the Dietary and Nutritional Survey of British Adults, in which persons of both sexes aged 16 to 64 years living in private households (excluding pregnant women) had been randomly selected from the United Kingdom Electoral Register. Main outcome measures were systolic blood pressure, diastolic blood pressure, and hypertension (defined as systolic blood pressure of > or = 140 mm Hg, diastolic blood pressure of > or = 90 mm Hg, or both, or receiving antihypertensive medication). RESULTS: After controlling for 24-hour urinary potassium excretion, age, obesity, alcohol intake, and season of interview, a single measure of 24-hour urinary sodium excretion was significantly associated with systolic blood pressure (P < or = .001), diastolic blood pressure (P < .05), and hypertension (P = .009). These associations persisted after controlling for many variables of blood chemistry and dietary intake. CONCLUSIONS: Sodium is positively associated with blood pressure over a range of sodium excretion rates from 70 to 400 mmol/d. This finding supports the international consensus that the risk of hypertension is lower when salt intake is lower and suggests that a proportion of the British population has a sodium excretion rate that is habitually low enough to have some preventive effect.

Adult↗

Adolescent-parent communication in self-harm.

PURPOSE: To examine the association between communication with parents and self-harm in 14-19-year-old adolescents. METHODS: A total of 36 female and 16 male adolescents presenting to the accident and emergency department of a general hospital; 52 hospital-based controls were interviewed and studied using the following scales: Parent-Adolescent Communication Scale, Family Adaptability and Cohesion Evaluation Scale, Adolescent-Family Inventory of Life Events and Changes Scale, Children's Depression Index, and Nowicki-Strickland Locus of Control Scale. RESULTS: The absence of a family confidant was very strongly associated with adolescent self-harm. Despite controlling for a wide range of possible causal factors, poorer parent-adolescent communication remained strongly associated with self-harm. The effect of poorer communication on self-harm was strongest in the group with and internal locus of control. CONCLUSIONS: Impairment of communication between adolescents and their parents may be important in the origins of adolescent self-harm.

Adolescent↗

Changes in self-reported skin type associated with experience of sunburning in 14-15 year old children of northern European descent.

Melanoma risk differs by sun-sensitive phenotype, of which self-reported skin type (tendency to burn, inability to tan) is an indicator. If self-reports of skin type are influenced by the amount of sun exposure subjects have had, the two principal determinants of risk are linked, and stratifying by skin type would bias the estimated effect of sun exposure. Our objective was to determine whether teenagers changed their self-reports of skin type after being sunburnt. A random sample (n = 364) of 14-15 year old schoolchildren of northern European ancestry self-assessed and self-reported their skin type before and after their summer holidays. Their responses had high correlation coefficients (girls 0.71, boys 0.54) for repeatability at 4 months, but subjects who sunburnt less (more) frequently than usual that summer revised their skin type assessment to be less (more) sun-sensitive afterwards. We conclude that these 14-15 year olds were influenced by a recent experience of sunburn when reporting their skin type. A more objective measure of phenotype is needed.

Adolescent↗

Assessment of habitual sun exposure in adolescents via questionnaire--a comparison with objective measurement using polysulphone badges.

The reliability and validity of sun exposure questions were examined in a group of 125 schoolchildren aged 14-15 years of northern European ancestry. We compared estimates of erythemally effective dose (EED) obtained from polysulphone badges worn on four consecutive weekend days in late spring to answers to several questions on habitual sun exposure. The polysulphone badge estimates accurately reflected the reported sun exposure of children and were highly correlated with responses to questions on habitual sun exposure obtained 12 months earlier. For the question "During weekends and school holidays, how much time do you usually spend in the sun each day", the Pearson correlation coefficients for the association with EED were 0.36 (girls) and 0.23 (boys). Adjusted for within-person variation in the EED measurements, the correlation coefficients were 0.65 (girls) and 0.43 (boys). For the question "Weekends and school holidays, where do you spend your time", the correlation coefficients were 0.18 (girls) and 0.32 (boys); the adjusted coefficients were 0.30 (girls) and 0.53 (boys). The findings suggest that "habitual' sun exposure in teenage children is a temporally stable behaviour that is reported with an acceptable degree of reliability and validity.

Adolescent↗

The contribution of changes in the prevalence of prone sleeping position to the decline in sudden infant death syndrome in Tasmania.

OBJECTIVE: To determine the independent contribution of changes in infant sleep position to the recent decline in sudden infant death syndrome (SIDS) rate in Tasmania. DESIGN: (1) A comparison of the whole population incidence of SIDS before and after an intervention to reduce the prevalence of prone sleeping position. (2) A within-cohort analysis of the contribution of sleep position and other exposures to the decline in SIDS after the intervention. SETTING: Tasmania, Australia. PARTICIPANTS: (1) All SIDS cases from 1975 through 1992. (2) A sample of one in five infants born in Tasmania who at perinatal assessment were scored to be at higher risk for SIDS since January 1988. Of 5534 infants included in the study, 39 later died of SIDS. INTERVENTIONS: Multiple public health activities to reduce the prevalence of the prone infant sleeping position in Tasmania and verbal information on the association between prone position and SIDS to cohort participants from May 1, 1991. MAIN OUTCOME MEASURE: Sudden infant death syndrome incidence. RESULTS: The Tasmanian SIDS rate decreased (P < .01) from 3.8 (95% confidence interval [CI], 3.5 to 4.2) deaths per 1000 live births from 1975 through 1990 to a rate of 1.5 (95% CI, 0.9 to 2.2) deaths per 1000 live births in 1991 through 1992. The SIDS mortality rate in the cohort by period of birth was 7.6 (95% CI, 4.9 to 10.3) deaths per 1000 live births for those born from May 1, 1988, through April 30, 1991, and 4.1 (95% CI, 1.3 to 7.0) deaths per 1000 infants for those born from May 1, 1991, through October 31, 1992. The prevalence of usual prone sleeping position at 1 month of age was 29.9% and 4.3% in these two cohorts, respectively (adjusted odds ratio, 0.11; 95% CI, 0.08 to 0.13). Logistic regression demonstrated that 70% of the SIDS rate reduction in the cohort could be accounted for by the decreased prevalence of the prone sleeping position. Other factors examined individually contributed to less than 10% of the SIDS rate reduction. CONCLUSIONS: The major contributing factor to the recent SIDS rate decline in Tasmania has been the reduction in the proportion of infants usually sleeping prone.

Cohort Studies↗

Comparative validity of a food frequency questionnaire for adults with IDDM.

OBJECTIVE: To investigate the characteristics of a food frequency questionnaire (FFQ) in measuring dietary intake in an adult insulin-dependent diabetes mellitus (IDDM) population. FFQs have been widely used in developed countries to assess usual dietary intake; however, information regarding the application of the method to individuals advised to follow a specific dietary regimen (such as people with IDDM) is scarce. RESEARCH DESIGN AND METHODS: The measurement of energy and macronutrients by an interviewer-administered FFQ was assessed in 84 adults, who were representative of adults with IDDM in Tasmania, Australia, by comparing it with 2 days of weighed dietary records. Mean daily energy and macronutrient intakes by each method were compared, and Pearson correlation coefficients were calculated for both unadjusted and energy-adjusted macronutrient intakes. RESULTS: The ratio of within-person to between-person variance in dietary estimates from weighed records was 0.53 for energy, 0.70 for fat, 2.55 for protein, 0.50 for carbohydrate, 0.78 for saturated fat, and 3.56 for dietary cholesterol. The correlation coefficient between the FFQ and a 2-day weighed dietary record for the same nutrients ranged from 0.38 for protein intake to 0.60 for saturated fat intake. The correlation coefficient between the FFQ and true usual dietary intake was estimated to be 0.60 for energy-adjusted fat intake, 0.36 for energy-adjusted protein intake, 0.72 for energy-adjusted carbohydrate intake, 0.55 for energy-adjusted saturated fat intake, and 0.77 for energy-adjusted cholesterol intake. CONCLUSIONS: People with IDDM had a low ratio of within-person to between-person variance in daily energy, fat, carbohydrate, saturate fat, and cholesterol intake. The performance of the FFQ in the IDDM population is consistent with similar questionnaires in nondiabetic populations; however, there was a significant decrease in the dietary energy estimate upon readministration of the questionnaire. Validation studies such as this are important to provide information to guide the design and analysis of investigations that use dietary questionnaires.

Adolescent↗

Victims of violence in Fiji.

OBJECTIVE: The aim of the paper is to examine the statistics for violence performed by self or others in Fiji during the period 1969-1989 in the following sub-classifications: (1) fatal vs non-fatal; (2) Fijian vs Indian; and (3) male vs female. METHOD: Crude rates per 100,000 were determined and the data sets were statistically examined. RESULTS: (1) Violence by self, which includes suicide and non-fatal injury by self, has significantly increased; (2) Indian violence by self has increased in both males and females; (3) suicide is 4 times more common than homicide, whereas non-fatal injury by others is 4 times more common than non-fatal injury by self; (4) non-fatal injury by self is 8 times more common than suicide, whereas non-fatal injury by others is over 100 times more common than homicide; (5) Indian violence by self is 6 times more common than Fijian violence by self, whereas Fijians experience violence by others 2.5 times more commonly than Indians; (6) female violence by self is 1.5 times more common than male violence by self, whereas male violence by others is 3 times more common than female violence by others; (7) the rates of suicide and homicide are low by international standards; and (8) Fijian violence by self is particularly low, but consistent with the low suicide rate of the indigenous populations in surrounding geographical regions. CONCLUSION: Our findings suggest that racial differences in violence are likely to be due to cultural factors.

Cause of Death↗

Sunburn associated with increased number of nevi in darker as well as lighter skinned adolescents of northern European descent.

The associations of sun exposure, sunburn, skin color, and other constitutional characteristics with the density of nevi (2 mm or more in diameter) were assessed in a study of 410 secondary school children ages 14-15 years in Tasmania, Australia. Skin color was estimated by using a chromameter that measures across the visible light spectrum (400-700 nm). Skin color and lifetime history of sunburn were significant predictors of nevus density on the arms and legs of girls and boys and on the shoulders and backs of boys. The nevus density ratios between the highest and lowest exposure groups were 2.85 for the arms and legs of boys (P < 0.01), 2.19 for the arms and legs of girls (P < 0.01), and 1.72 (P = 0.03) for the shoulders and backs of boys. The increase in nevus density appeared to occur at lower levels of lifetime sunburn in children with light or medium skin than it did in children with darker skin. Darker-skinned children with a history of many sunburns ( > or = 11 lifetime sunburns) had a similar number of nevi compared with their lighter-skinned peers.

Adolescent↗

Brain cancer incidence, mortality and case survival: observations from two Australian cancer registries.

Data from 2 Australian cancer registries covering a population of 1.7 million people were combined for the purposes of analysing brain cancer incidence, mortality and survival patterns for the time period 1978 through 1992. A total of 1,752 cases of primary brain cancer were registered, representing age-standardised incidence rates of 6.7 per 100,000 in men and 4.6 in women. Histological confirmation was available for 94% of cases. The incidence rate among persons aged 75 or over was higher during 1986-1992 than during 1978-1985, the rate for men increasing from 16.3 to 26.2 and that for women increasing from 9.7 to 18.0. The largest increases in this age group occurred for cases of glioblastoma multiforme. During the study period, 1,411 brain cancer deaths were notified to the 2 registries at age-standardised rates of 5.3 in men and 3.4 in women. Mortality rates among persons aged 75 years or older were higher during 1986-1992 than 1978-1985, increasing from 15.7 to 28.4 in men and from 10.1 to 15.3 in women. Only among men aged 15-49 years was a decline in mortality rates observed, from 3.3 to 2.4. Survival analyses indicated that age and histological type were the most powerful prognostic indicators. There was no improvement in 5-year survival for any of the age groups or histological types. An improvement in 36-month survival was noted for the 15-49 year age group diagnosed with gliomas other than glioblastoma multiforme.

Adolescent↗

Suicide and self-harm in Tasmanian children and adolescents.

OBJECTIVES: To examine rates of suicide by Tasmanians less than 20 years of age, to compare them with rates for Australia as a whole, and to report a clinical study of child and adolescent self-harm in Tasmania. DESIGN: Australian Bureau of Statistics data on suicides by 0-19-year-olds in Tasmania and Australia and population estimates were used to calculate and compare suicide rates for the period 1965-1991. The self-harm study involved 36 females and 16 males presenting to the accident and emergency department of a general hospital. They were studied by means of structured interview and scales of personal/family functioning and beliefs. Controls were individually matched with patients with no psychiatric condition. RESULTS: During 1965-1991, the suicide rate in Tasmanian males aged 15-19 years was higher than that of mainland Australian males and had increased during the last 10 years of this period. Suicide rates for males, both in Tasmania and mainland Australia, were higher than the corresponding rates for females. Among females aged 10-14 years or 15-19 years, the rates for Tasmania were not different from those of the mainland counterparts. The rate for 15-19-year-old Tasmanian females was higher during the last decade of the study period than in earlier years. Common motivations for self-harm were to die or to escape an impossible situation, rather than to attract the attention of others. Most adolescents had serious personal and interpersonal problems, usually involving family dysfunction, including parental separation, physical abuse and lack of a family confidant, when compared with controls. Ingestion of medication (most frequently paracetamol) was the most common method of self-harm. CONCLUSIONS: The suicide rate in 15-19-year-old Tasmanian males is higher than the mainland rate and rising. Self-harm in adolescence is associated with serious personal and interpersonal problems which must be identified before effective counselling can begin. The formation of multidisciplinary teams for the immediate assessment and support of self-harming adolescents and their parents is recommended.

Adolescent↗

Higher lung cancer rates in young women than young men: Tasmania, 1983 to 1992.

In a background of changing lung cancer rates in the past decade, mean incidence and mortality rates for persons aged 25-44 in Tasmania for the decade 1983 through 1992 were examined using Tasmanian Cancer Registry data. The smoking behavior of Tasmanian adults and schoolchildren was also investigated, using data from a social survey conducted by the Australian Bureau of Statistics and from five secondary school smoking surveys. The Tasmanian age-standardized lung cancer incidence rates in 25-44 year olds for the 10-year period were 6.2 per 100,000 females and 3.3 per 100,000 males. Mean rates of incidence were higher for females than for males (P = 0.02). The corresponding mortality rates were 4.2 in females and 2.4 in males (P = 0.08). The prevalence of smoking by adult Tasmanian women is higher than that for other Australian women (P < 0.05), and their duration of smoking is longer (P < 0.01). Tasmanian schoolgirls have a higher smoking prevalence than Australian mainland schoolgirls (P = 0.01) and higher prevalence than Tasmanian schoolboys (P = 0.01). The data suggest that smoking prevalence among teenagers passed that for males only a decade before the observed excess of female incident cases among 25-44 year olds in Tasmania.

Adenocarcinoma↗