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PubMed2004

Prevalence and severity of anemia and iron deficiency: cross-sectional studies in adolescent schoolgirls in western Kenya.

OBJECTIVE: Anemia is a major public health concern in preschool children and pregnant women in the developing world. While many studies have examined these two at-risk groups, there is a paucity of data on anemia in adolescents living in developing countries in the complex ecologic context of poverty, parasitism, and malnutrition. We evaluated the prevalence, severity, and risk factors of anemia in adolescent schoolgirls in an area with intense malaria transmission in western Kenya. DESIGN: Two cross-sectional surveys were conducted, using a multistage random sample design. SETTING: Public primary schools in an area with intense malaria transmission in western Kenya. SUBJECTS: A total of 648 randomly selected adolescent schoolgirls aged 12-18 y. RESULTS: The prevalence of anemia (Hb <120 g/l) was 21.1%; only one girl had an Hb less than 70 g/l. Ferritin levels were available from a subsample of 206 girls. The prevalence of iron deficiency (ferritin <12 microg/l) was 19.8, and 30.4% of anemic girls were iron deficient. Malaria and schistosomiasis were the main risk factors for anemia in younger girls (12-13 y), while menstruation was the principal risk factor in older girls (14-18 y). CONCLUSIONS: Iron deficiency and anemia in school-attending girls in western Kenya were more prevalent than in developed countries, but considerably less prevalent than in preschool children and pregnant women from the same study area. Our findings are consistent with other recent school-based surveys from western Kenya, but not with recent community- and school-based cross-sectional surveys from other parts of sub-Saharan Africa. It deserves further study to determine if adolescent girls not attending school are at higher risk of anemia.

Adolescent↗
PubMed1999

Physiological arousal and sensation-seeking in female fruit machine gamblers.

AIMS: To examine changes in physiological arousal, as indexed by heart rate, during fruit machine gambling while controlling for the confounding effect of movement and as a function of winning and losing, and to examine relationships between sensation-seeking, self-reported arousal during gambling, heart rate during gambling and frequency of gambling. SAMPLE, DESIGN AND MEASUREMENTS: Heart rate and subjective arousal were recorded in a sample of 32 female fruit machine players before, during and after the gambling process. At baseline measures were taken of sensation-seeking, self-reported arousal during gambling and frequency of gambling. A simulation of the behaviour used to operate fruit machines was used during baseline measurement. FINDINGS: Significant increases in heart-rate over movement controlled baselines were observed within participants during gambling, but only in those who won during play. No correlations between HR levels and subjective arousal were found. However, striking negative correlations between sensation-seeking and frequency of gambling, and between subjective arousal and frequency were present. CONCLUSIONS: Gambling alone is not enough to induce increases in HR levels for female fruit machine gamblers; the experience of winning or the anticipation of that experience is necessary to increase HR levels. In addition sensation-seeking appears to be negatively associated with this kind of gambling behaviour.

Adult↗
PubMed2001

Gender differences, physiological arousal and the role of winning in fruit machine gamblers.

AIMS: To examine gender differences in changes in physiological arousal as indexed by heart rate during fruit machine gambling while controlling for the confounding effect of movement and as a function of winning and losing, and to examine relationships between sensation-seeking, self-reported arousal during gambling, heart rate during gambling and loss of control of gambling behaviour. SAMPLE, DESIGN AND MEASUREMENTS: Heart rate and subjective arousal were recorded in a sample of 22 male and 20 female fruit machine players before, during and after the gambling process. At baseline measures were taken of sensation seeking, self-reported arousal during gambling and loss of control of gambling. A simulation of the behaviour used to operate fruit machines was used during baseline measurement. FINDINGS: Significant increases in heart-rate over movement controlled baselines were observed within participants during gambling. However, for the losing group these differences were slight compared to the increases found when participants won during play. Furthermore, winning/losing was the only variable among a range of variables which was a significant predictor of heart-rate increase during play over a baseline control. Additionally HR levels of males and females behaved the same way in relation to the manipulations. Significant correlations between HR during play and the measures of both subjective arousal and sensation seeking were also present. CONCLUSIONS: Winning during gambling is essential in order to maintain increased HR levels over baseline after play. Subjective arousal and sensation seeking may be predictors of levels of arousal experienced during play.

Adult↗
PubMed2004

Estimation of the number of stellate cells in a liver with the smooth fractionator.

To better evaluate the activation and proliferative response of hepatic stellate cells (HSC) in hepatic fibrosis, it is essential to have sound quantitative data in non-pathological conditions. Our aim was to obtain the first precise and unbiased estimate of the total number of HSC in the adult rat, by combining the optical fractionator, in a smooth sampling design, with immunocytochemistry against glial fibrillary acidic protein. Moreover, we wanted to verify whether there was sufficiently relevant specimen inhomogeneity that could jeopardize the high expected estimate precision when using the smooth fractionator design for HSC. Finally, we wanted to address the question of what sampling scheme would be advisable a priori for future studies. Microscopical observations and quantitative data provided no evidence for inhomogeneity of tissue distribution of HSC. Under this scenario, we implemented a baseline sampling strategy estimating the number (N) of HSC as 207E(06) (CV = 0.17). The coefficient of error [CE(N)] was 0.04, as calculated by two formerly proposed approaches. The biological difference among animals contributed congruent with 95% to the observed variability, whereas methodological variance comprised the remaining 5%. We then carried out a half reduction of sampling effort, at the level of both sections and fields. In either occasion, the CE(N) values were low ( congruent with 0.05) and the biological variance continued to be far more important than methodological variance. We concluded that our baseline sampling (counting 650-1000 cells/rat) would be appropriate to assess the lobular distribution and the N of HSC. However, if the latter is the only parameter to be estimated, around half of our baseline sampling (counting 250-600 cells/rat) would still generate precise estimates [CE(N) < 0.1], being in this case more efficient to reduce the number of sections than to reduce the sampled fields.

Animals↗
PubMed1998

Lifetime and twelve-month prevalence rates of major depressive episodes and dysthymia among Chinese Americans in Los Angeles.

OBJECTIVE: The authors' goal was to estimate the lifetime and 12-month rates of major depressive episodes and dysthymia for Chinese Americans who reside in Los Angeles. This effort, the Chinese American Psychiatric Epidemiological Study, is the first large-scale community psychiatric epidemiological study on an Asian American ethnic group that used DSM-III-R criteria for major depressive episodes and dysthymia. METHOD: A multi-stage sampling design was used to select respondents for participation in the survey. The sample included 1,747 adults, 18-65 years of age, who resided in Los Angeles County and who spoke English, Mandarin, or Cantonese. RESULTS: Approximately 6.9% of the respondents had experienced an episode of major depression and 5.2% had had dysthymia in their lifetime. The 12-month rates of depressive episode and dysthymia were 3.4% and 0.9%, respectively. The most consistent correlate of lifetime and 12-month depressive episode and dysthymia was social stress, measured by past traumatic events and recent negative life events. CONCLUSIONS: The Chinese American Psychiatric Epidemiological Study provides a rare opportunity to investigate the heterogeneity within a single Asian American ethnic group, Chinese Americans, and to identify the subgroups among Chinese Americans who may be most at risk for mental health problems.

Acculturation↗
PubMed2003

HER2 status in non-small cell lung cancer: results from patient screening for enrollment to a phase II study of herceptin.

PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease.

Adenocarcinoma↗
PubMed1993

Tobacco and alcohol use among Australian secondary school students in 1990.

OBJECTIVE: To obtain up-to-date prevalence estimates of tobacco smoking and alcohol drinking among Australian secondary students, and to compare these estimates with those obtained from similar studies conducted in 1984 and 1987. DESIGN: Data were collected from 24,892 secondary students aged 12 to 17 years from all Australian States and the Northern Territory. A stratified two-stage sample design was used. First, a random sample of schools was selected and second, for each school a sample of 80 students was randomly selected from predetermined year levels. A total of 351 schools participated in the survey. Students completed an anonymous, self-administered questionnaire on their smoking and drinking behaviours. RESULTS: The prevalence of current smoking (defined as having smoked at least one cigarette in the week preceding the survey) was found to increase with age to reach a peak of 25% among 16-year-old boys and 29% among girls aged 15 years. From the age of 13, smoking was more prevalent among girls than boys. Among current smokers, boys were heavier smokers than were girls. Unlike smoking, drinking was slightly more prevalent among boys than girls; boys were heavier drinkers. The proportion consuming at least one alcoholic drink in the week before the survey rose with age to a peak of 51% of boys and 46% of girls aged 17 years. Comparisons with data obtained from a similar survey conducted in 1987 showed that there had been a decrease in the proportion of 12 to 15 year olds smoking. The prevalence of drinking among both 12 to 15 year olds and 16 to 17 year olds was significantly lower in 1990 than 1987. CONCLUSIONS: While the continuing downward trends in smoking and drinking among younger students is encouraging, the results show that there are still large numbers of students smoking and drinking.

Adolescent↗
PubMed2026

Non-smoked cannabis consumption formats and Cannabis Use Disorder severity in an illicit setting: Evidence from Chile, 2020-2024.

BACKGROUND: Cannabis Use Disorder (CUD) has become an increasing public health burden, particularly in Chile. Non-smoked cannabis formats and products have been independently associated with CUD but remain understudied in the region. This study compares CUD severity among individuals aged 12 to 65 in Chile who consume cannabis via edibles, vaporization or both versus those who exclusively smoke it. METHODS: We obtained secondary data from three waves of the Chilean National Survey on Drugs in the General Population (ENPG), a three-stage stratified probabilistic sampling design study conducted in 2020, 2022, and 2024. Our pooled cross-sectional sample included individuals (n = 3543) who reported cannabis use in vaped, edible, both vaped and edible or exclusively smoked format in the past 12 months. We used a partial proportional odds model to estimate the association between CUD severity and consumption formats. RESULTS: Cannabis vaping group showed higher odds of presenting at least mild CUD (OR = 6.21 [95% CI: 3.75-10.3]), as did the edible group (OR = 1.73 [95% CI: 1.08-2.78]) and both group (OR = 5.92 [95% CI: 2.72-12.87]), compared to exclusive smokers. However, only the vaped group demonstrated higher odds for all severity levels. CONCLUSION: Compared with exclusive smokers, users of vaporizers and/or edibles showed a stronger association with CUD. This association may be explained by consumption patterns and total THC exposure. Further research is needed to characterize the average THC exposure by consumption format, acknowledging contextual confounders such as the legal framework.

Humans↗
PubMedDate not supplied

Comparison of methods for estimating drug coverage for filariasis elimination, Leogane Commune, Haiti.

In the global effort to eliminate lymphatic filariasis, annual mass treatments are conducted with diethylcarbamazine (DEC) or ivermectin, combined with albendazole. The success of this strategy depends on achieving high levels of drug coverage, which reduces the number of persons with circulating microfilariae so that transmission of the parasite is interrupted. Because resources are often limited, a simple, inexpensive, and reliable method to estimate drug coverage is needed. During the period December 2000 to February 2001, three methods were used to assess drug coverage in Leogane Commune, Haiti: a probability survey using a cluster sample design (n = 1421 persons); a distribution-point survey based on a convenience sample of houses near the distribution points (n = 4341 persons); and a survey based on a convenience sample of primary schools (n = 5036 children). The coverage estimations were 71.3% (95% CI 66.7-75.9), 73.6% (95% CI 70.1-77.0), and 77.8% (95% CI 73.5-82.1), respectively. Survey costs for the probability, distribution point, and school surveys were US$2217, US$979, and US$312, respectively. The 2 convenience sampling methods provided point estimates of drug coverage that were similar to those of the probability survey. These methods may have a role for monitoring drug treatment coverage between less frequent, but more costly, probability sample surveys.

Adult↗
PubMed2006

Metal distributions in New Orleans following hurricanes Katrina and Rita: A continuation study.

In late October 2005, twenty-seven metals were determined in soils and sediment layers deposited by floodwaters (flood sediments) within New Orleans, Louisiana. Samples originated from 43 sites along four transects, at an industrial canal, and near the Superdome. The sampling design encompassed flooded and nonflooded areas as well as differing economic strata within the city. Results from this effort confirmed findings of our previous study designed to quantify contaminant profiles in the aftermath of Hurricane Katrina. The expanded sampling from this most recent investigation revealed that arsenic (As) and lead (Pb) concentrations exceeded United States Environmental Protection Agency (USEPA) soil screening criteria indiscriminately throughout the city. However, As and Pb concentrations were lower along St. Charles Avenue, an area largely unaffected by hurricane related flooding. Toxicant concentrations did not exceed soil screening criteria values for lead within any flood sediments or for 32 of 37 soil samples, but arsenic concentrations in 40 of 43 samples exceeded screening criteria.

Arsenic↗
PubMed2002

European adolescent substance use: the roles of family structure, function and gender.

OBJECTIVES: The aim of this study was, first, to explore family structure and measures of family functioning in relation to adolescent substance use and secondly, to establish if these relationships differed according to gender or according to the city of origin of the sample. DESIGN, SETTING, PARTICIPANTS: The study surveyed pupils aged 14-15 years in representative samples drawn from five European cities: Newcastle upon Tyne, Dublin, Rome, Bremen and Groningen. Data were obtained on 3984 participants in relation to their substance use, living with both biological parents, confiding in parents and grandparents. and supervision, as well as other variables representing delinquency, social class and drug availability. RESULTS: Living with both parents was associated with reduced levels of drug use in four cities but not in Dublin, due perhaps to the high availability from peers in that city. It was not associated with reduced levels of regular drinking. The effect of confiding in mother was evident in all cities and in relation to substance use in general. However, when a delinquency variable was added to the logistic regressions, its significance in relation to polydrug use disappeared. Supervision was somewhat more important in relation to male than female drug use. CONCLUSION: Living with both parents is a less robust barrier to substance use than qualitative aspects of family life, particularly attachment to mothers. The latter is a robust inhibitor of substance use irrespective of regional differences in drug availability, weakening only in the face of more generally problematic behaviour. Perhaps because of their greater tendency to risk-taking or rule breaking, supervision appears more important for male than female drug use. These findings underscore the role of families, but especially that of mothers, in regulating the substance-related behaviour of young people.

Adolescent↗
PubMed2000

Non-uniform systematic sampling in stereology.

Non-uniform systematic sampling designs in stereology are studied. Various methods of constructing non-uniform systematic sampling points from prior knowledge of the measurement function are presented. As an example, we consider area estimation from lengths of linear intercepts. The efficiency of two area estimators, based on non-uniform sampling of parallel lines, is compared to that of the classical 2D Cavalieri estimator, based on uniform sampling, in a sample of planar profiles from transverse sections of 41 small myelinated axons. The comparison is based on simulations. It is concluded that for profiles of this type one of the non-uniform sampling schemes is more efficient than the traditional uniform sampling scheme. Other examples where non-uniform systematic sampling may be used are in area estimation from lines emanating from a fixed point, area estimation from concentric circles or spirals and curve length estimation from sweeping lines. It is shown that proportional-to-size sampling is a special case of non-uniform systematic sampling. Finally, the effect of noise in the observations is discussed.

Axons↗
PubMed1997

Chronic disability trends in elderly United States populations: 1982-1994.

Statistically significant declines in chronic disability prevalence rates were observed in the elderly United States population between the 1982 and 1989 National Long Term Care Surveys (NLTCS). The 1994 NLTCS was used to investigate whether disability rate declines continued to 1994. The 1982, 1984, 1989, and 1994 NLTCS employ the same sample design and instrumentation so that trends in disability can be estimated with minimal sampling and measurement bias. Age (5-year categories from 65 to >95)-specific rates were calculated for the 1982 NLTCS and applied to United States Census Bureau estimates of the 1994 population to calculate chronic disability prevalence rates adjusted for aging in the United States population aged > 65. The 1982 age standardized rates were compared with 1994 NLTCS estimates. The prevalence of disability estimated for 1994 (21.3%) was 3.6% lower than the 1982 age standardized rate (24.9%)-a highly significant reduction (t = -8.5; P << 0.0001). Of the 3.6 percentage point decline in prevalence, 1.7% occurred in the 5 years between 1989 and 1994-compared with the 1.9% decline in the 7 years between 1982 and 1989. Both declines are significant. Because of the shorter time period, the per year decline in disability prevalence from 1989 to 1994 was greater than that from 1982 to 1989. Given the higher acute and long-term care service needs of the disabled elderly population, Medicare, Medicaid, and private health expenditures may be dramatically lower than if declines had not occurred.

Activities of Daily Living↗
PubMed2006

Mixed-effect models for evaluating multiple measures of atrazine exposure among custom applicators.

The exposure of custom (or commercial) applicators to the herbicide atrazine was measured in environmental (hand wash and dermal patch) and biological (urine and saliva) samples. Surrogate exposure data, such as amount of atrazine sprayed, were also collected. A systematic sampling design was used that included both spray and nonspray days. Fifteen applicators were sampled 5 to 7 days each during a 6-week spring spray season for a total of 89 sampled days. Mixed-effect regression modeling was used to examine the relationship among the surrogate, environmental, and biological atrazine exposure measures. Surrogate measures of atrazine application (either kg of atrazine sprayed or spray atrazine [yes/no]) were significantly associated with increased levels of atrazine or atrazine equivalents (eq) in hand wash, thigh patch, 4-6 p.m. saliva, and 24-hour urine samples. Two days of spraying information (day of sampling and day before sampling) were needed to optimally estimate atrazine biomarkers in the biological samples, whereas only 1 day of spraying information (day of sampling) was needed to estimate atrazine levels in the environmental samples. Thigh and hand atrazine exposures were significantly associated with increased atrazine and atrazine eq. levels in the 4-6 p.m. saliva and 24-hour urine samples, respectively. Levels of 4-6 p.m. salivary atrazine were also significantly associated with increased levels of 24-hour urinary atrazine eq. Atrazine levels in the 4-6 p.m. saliva samples tracked most closely with evening and next morning urinary atrazine eq. Number of days into the study at the time of sample collection predicted urinary and salivary atrazine levels independent of other fixed effects. These results indicate that either surrogate, environmental, or biological exposure measures can be used in appropriately specified models to estimate urinary and salivary atrazine biomarker levels.

Air Pollutants, Occupational↗
PubMed1998

Role of body mass index in the prediction of all cause mortality in over 62,000 men and women. The Italian RIFLE Pooling Project. Risk Factor and Life Expectancy.

STUDY OBJECTIVE: To evaluate the relation of body mass index (BMI) to short-term mortality in a large Italian population sample. DESIGN: Within the Italian RIFLE pooling project, BMI was measured in 47 population samples made of 32,741 men and 30,305 women ages 20-69 years (young 20-44, mature 45-69). Data on mortality were collected for the next six years. MAIN OUTCOME MEASURES: Age adjusted death rates in quintile classes of BMI and Cox proportional hazards models with six year all causes mortality as end point, BMI as covariate and age, smoking, systolic blood pressure as possible confounders were computed. Multivariate analysis was tested in all subjects and after the exclusion of smokers, early (first two years) deaths, and both categories. RESULTS: The univariate analysis failed to demonstrate in all cases a U or inverse J shaped relation. The Cox coefficients for the linear and quadratic terms of BMI proved significant for both young and mature women. The minimum of the curve was located at 27.0 (24.0, 30.0, 95% confidence limits, CL) and 31.8 (25.5, 38.2, 95% CL) units of BMI, for young and mature women respectively. Similar findings were obtained even when exclusion were performed. No relation was found for young men while for mature adult men only the model for all subjects retained significant curvilinear relation (minimum 29.3; 22.4, 36.2, 95% CL). CONCLUSION: These uncommon high values of BMI carrying the minimum risk of death seems to be in contrast with weight guidelines. A confirmation of these findings in other population groups might induce the consideration of changes in the suggested healthy values of BMI.

Adult↗
PubMed1999

Clinical use of continuous arterial blood gas monitoring in the pediatric intensive care unit.

CONTEXT: Continuous arterial blood gas monitoring is a new technology based on the combination of opto-chemical and fiber-optic detectors that can measure pH, PCO2, PO2, and temperature on a continuous basis via a sensor placed in an artery. OBJECTIVE: To evaluate this technology in pediatric patients who would normally require frequent arterial blood gas sampling. DESIGN: A criterion standard study in which the results of arterial blood gas samples measured by the laboratory analyzer were compared with the sensor readings. SETTING: A pediatric intensive care unit of a tertiary referral center. PATIENTS: Children with severe respiratory failure who required frequent arterial blood gas sampling and who had a 20-gauge arterial line in either a radial or femoral site. RESULTS: Twenty-four patients with a mean age of 6.4 years (range 1-21 years) had a sensor placed. Sensors were in place for a mean of 101 +/- 62 hours. Eighteen patients underwent continuous monitoring for at least 24 hours or until no longer clinically necessary. There were 414 pairs of blood gas samples obtained. The bias/precision for pH was 0.005/0.030; for PCO2, -1.8/6.3 mm Hg; and for PO2, 1.2/24 mm Hg. The correlation (r value) between the sensor readings and the blood gases were pH 0. 960, PCO2 0.927, PO2 0.813 (P <.01 for all values). The bias and precision for PO2 levels < 70 mm Hg were 0.057/9.34 mm Hg. There were no complications from sensor placement. Continuous blood gas monitoring allowed immediate recognition of clinical changes. CONCLUSION: The continuous arterial blood gas sensor is capable of clinically accurate blood gas measurements. This technology provides the clinician with immediate data that can allow rapid interventions in unstable patients.

Adolescent↗
PubMed1991

Outcome of 1500 consecutive chorionic villus samplings.

OBJECTIVE: To evaluate the clinical complications and diagnostic problems of chorionic villus sampling. DESIGN: A pragmatic retrospective analysis. SETTING: Tertiary obstetric referrals mostly to private practice; sampling carried out at Royal Prince Alfred Hospital; diagnostic analysis usually at Oliver Latham Laboratory, or the Clinical Immunology Research Centre, Royal Prince Alfred Hospital, New South Wales. PATIENTS: 1500 women in the first trimester of pregnancy requesting prenatal diagnosis because of a risk of chromosomal or inherited genetic disorder in the fetus. INTERVENTIONS: Ultrasound-guided passage of a catheter into the chorion through the cervix. MAIN OUTCOME MEASURES: Incidence of unintended abortion, preterm births, low weight infants and discrepant karyotypes. RESULTS: There were 42 unintended abortions (3.0%), about 0.4% higher than the background abortion rate in women of similar age. Abortion did not occur more frequently in women with vaginal bleeding earlier in that pregnancy. Rates of preterm births and birth of low birthweight infants did not differ from the general population. A second diagnostic test was required in 68 women (4.5%). Mosaicism and tetraploidy were usually confined to the chorion. CONCLUSION: Chorionic villus sampling is an acceptable diagnostic test. Amniocentesis should be offered to patients who show mosaicism or tetraploidy.

Abortion, Spontaneous↗
PubMed2005

Use of prescribed medications in a South Australian community sample.

OBJECTIVE: To determine the extent of self-reported use of prescription medications in an Australian community sample. DESIGN, SETTING AND PARTICIPANTS: Face-to-face interviews with a random, representative sample of the South Australian population (aged > or = 15 years) living in metropolitan and rural areas. The study, a Health Omnibus Survey, was conducted between March and June 2004. MAIN OUTCOME MEASURES: Reported number of prescribed medications used per person, most common categories of medication, and use by individuals of multiple medications for the same body system. RESULTS: From 4700 households selected, 3015 participants were interviewed (65.9% response rate). Of respondents, 46.8% were using prescribed medications; 171 respondents (5.7%) were taking six or more medications, and four were taking 16 or more; 23.2% were using medications for the cardiovascular system, with 11.9% using agents acting on the renin-angiotensin system. Prescription medication use increased with age, with over 10% of respondents aged > or = 55 years using six or more medications. CONCLUSIONS: Use of multiple prescribed medications was common, with the potential for significant drug interactions. Assuming a similar pattern of medication use Australia-wide, reducing the number of prescribed medications by one for people taking six or more medications would save the federal government about 380 million dollars a year.

Adolescent↗