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Biomedical subjects

J C Anthony

Publications and source records attributed to J C Anthony.

At least 55 records · Page 3Linked to original sources
PubMed1999

APOE-epsilon4 count predicts age when prevalence of AD increases, then declines: the Cache County Study.

OBJECTIVE: To examine the prevalence of Alzheimer's disease (AD) and other dementias in relation to age, education, sex, and genotype at APOE. Recent studies suggest age heterogeneity in the risk of AD associated with the APOE genotype and a possible interaction between APOE-epsilon4 and female sex as risk factors. We studied these topics in the 5,677 elderly residents of Cache County, Utah, a population known for long life expectancy and high participation rates. METHODS: We screened for dementia with a brief cognitive test and structured telephone Dementia Questionnaire, then examined all individuals with apparent cognitive symptoms and a sample of others. We estimated age-specific prevalence of AD and other dementias and used multiple logistic regression models to describe relation of AD prevalence to age, sex, education, and APOE genotype. RESULTS: We found 335 demented individuals, 230 (69%) with definite, probable, or possible AD (positive predictive value versus autopsy confirmation 85%). The adjusted prevalence estimate for AD was 6.5% and for all dementias 9.6%. After age 90, the adjusted prevalence estimate for AD was 28% and for all dementias 38%. Regression models showed strong variation in AD prevalence with age, sex, education, and number of epsilon4 alleles (effect of epsilon2 not significant). Models were improved by a term for age-squared (negative coefficient) and by separate terms for interaction of age with presence of one or two epsilon4 alleles. An association of AD with female sex was ascribable entirely to individuals with epsilon4. CONCLUSIONS: In participants with no epsilon4 alleles, the age-specific prevalence of AD reached a maximum and then declined after age 95. In epsilon4 heterozygotes a similar maximum was noted earlier at age 87, in homozygotes at age 73. Female sex was a risk factor for AD only in those with epsilon4. The epsilon4 allele accounted for 70% of the population attributable risk for AD.

Age Distribution↗
PubMed1999

Level of education and injecting drug use among African Americans.

Drawing upon a nationally representative survey sample of African American (AA) drug injectors and non-injectors, this study tests for a suspected causal association between dropping out of school and the occurrence of injecting drug use (IDU), which remains a major cause of human immunodeficiency virus (HIV) transmission in this population. The data are from public use files of the National Household Surveys on Drug Abuse (NHSDA) conducted between 1991 and 1995. From within the NHSDA's nationally representative sample of adult household residents, a total of 389 AA adults with a history of IDU were matched on neighborhood of residence with 2253 AA adults with no history of IDU. The conditional form of multiple logistic regression was used to estimate the relative risk of having injected a drug for school dropouts relative to a reference category of AA who received the high school diploma but did not go to college. AAs who dropped out of high school were an estimated two times more likely to have injected drugs. With statistical adjustment for age, sex, and Hispanic background, the estimated association was 1.9 (95% confidence interval (C.I.) = 1.3-2.6, P<0.001). Contrary to our advance hypothesis, earning the graduate equivalency certificate (GED) did not seem to affect the magnitude of excess risk for having started IDU (adjusted odds ratio (aOR) = 2.3, 95% C.I. = 1.4-3.8, P<0.001). Hence, school dropout prevention might reduce the risk of IDU per se, in addition to the many other general benefits of educational attainment. The issue of GED-associated reduced risk of IDU remains open for future study.

Adolescent↗
PubMed1999

Job strain and non-medical drug use.

In this study, the Karasek demand/control formulation of job strain, initially used in research on cardiovascular health, has been extended to drug use. Full-time nurses (n = 2375), all participants in a national anonymous mailed survey, were an estimated 1.5 times more likely to be a recent non-medical drug user if they had a high strain job as compared to nurses in low strain jobs. The psychosocial work environment might influence whether nurses become and remain non-medical drug users, over and above the risk-modifying functions related to nurses' individual vulnerabilities and their greater access to controlled substances.

Adult↗
PubMed1999

Cannabis use and cognitive decline in persons under 65 years of age.

The purpose of this study was to investigate possible adverse effects of cannabis use on cognitive decline after 12 years in persons under age 65 years. This was a follow-up study of a probability sample of the adult household residents of East Baltimore. The analyses included 1,318 participants in the Baltimore, Maryland, portion of the Epidemiologic Catchment Area study who completed the Mini-Mental State Examination (MMSE) during three study waves in 1981, 1982, and 1993-1996. Individual MMSE score differences between waves 2 and 3 were calculated for each study participant. After 12 years, study participants' scores declined a mean of 1.20 points on the MMSE (standard deviation 1.90), with 66% having scores that declined by at least one point. Significant numbers of scores declined by three points or more (15% of participants in the 18-29 age group). There were no significant differences in cognitive decline between heavy users, light users, and nonusers of cannabis. There were also no male-female differences in cognitive decline in relation to cannabis use. The authors conclude that over long time periods, in persons under age 65 years, cognitive decline occurs in all age groups. This decline is closely associated with aging and educational level but does not appear to be associated with cannabis use.

Adult↗
PubMed1999

Comparative epidemiology of initial drug opportunities and transitions to first use: marijuana, cocaine, hallucinogens and heroin.

The earliest stages of involvement with illicit drugs have been understudied. In a recent report, we examined initial opportunities to try marijuana and transitions from first opportunity to first use of that drug. This report extends that work by investigating early involvement with cocaine, heroin, and hallucinogens as well. We examine sex and race ethnicity differences in estimates of having a drug opportunity, and in the probability of progressing from having an opportunity to try a drug to actually using the drug. Self-report interview data collected for the National Household Surveys on Drug Abuse (NHSDA) from 1979 to 1994 were analyzed. Results showed that an estimated 51% of US residents have had an opportunity to try marijuana; comparative estimates for cocaine, hallucinogens, and heroin are 23, 14, and 5%, respectively. Among those who eventually used each drug, the vast majority made the transition from first opportunity to first use within 1 year. Males were more likely than females to have opportunities to try these drugs, but were not more likely than females to progress to actual use once an opportunity occurred. Time trends indicate recent increases from 1990 to 1994 in the estimated probability of using an illicit drug once an opportunity occurs, particularly for hallucinogens. Exploratory analyses on race ethnicity yielded some interesting leads for future research. This study sheds light on the epidemiology of the earliest stages of drug involvement in the USA. Implications for prevention efforts and for our understanding of sex differences in drug involvement are discussed.

Adolescent↗
PubMed1999

Sadness in older persons: 13-year follow-up of a community sample in Baltimore, Maryland.

BACKGROUND: Our prior psychometric work suggested that older adults interviewed in 1981 in a community survey were less likely than younger adults to report dysphoria. We hypothesized that this would also be true of older adults interviewed 13 years later. METHODS: This study is a population-based 13-year follow-up survey of community-dwelling adults living in East Baltimore in 1981. Subjects were the continuing participants of the Baltimore Epidemiologic Catchment Area Program. After excluding 269 adults who were 65 years of age and older at initial interview in 1981, 1651 adults remained (347 aged 65 years and older and 1304 who were 30-64 years-old at follow-up). We applied structural equations with a measurement model for dichotomous data (the MIMIC -- multiple indicators, multiple causes -- model) to compare symptoms between adults who were 65 years and older at follow-up with younger adults, in relation to the nine symptom groups comprising the diagnostic criteria for major depression, adjusting for several potentially influential characteristics (namely, gender, self-reported ethnicity, educational attainment, cognitive impairment, marital status and employment). RESULTS: Older adults were less likely to endorse sadness as evidenced by a direct effect coefficient of -0.335 (95% Confidence Interval -0.643, -0.027). After adjusting for several potentially influential characteristics, the direct effect of age was substantially unchanged (-0.298 (95% CI -0.602, 0.006)). CONCLUSIONS: Older adults in 1994, like older adults in 1981, were less likely to endorse sadness than younger persons. This finding suggests, but does not prove, that the observed age difference in reporting depression does not reflect a cohort effect.

Adult↗
PubMed1999

Male-female differences in the earliest stages of drug involvement.

AIMS: To examine whether male-female differences in rates of drug use could be traced back to differences in rates of exposure to initial opportunities to try drugs, rather than to sex differences in the probability of making a transition to use, once opportunity has occurred. DESIGN: Cross-sectional sample survey research with nationally representative samples and retrospective assessments. SETTING: United States, 1979-94. PARTICIPANTS: Respondents were 131,226 residents aged 12 years and older, recruited for the National Household Surveys on Drug Abuse by multi-stage probability sampling at nine time points. MEASUREMENTS: Estimated proportion of males and females with an opportunity to use marijuana, cocaine, hallucinogens and heroin; proportions reporting use among those having an opportunity to use each drug; proportion making a "rapid transition" from initial opportunity to initial use. FINDINGS: For each survey year, males were more likely than females to have an initial opportunity to use drugs. However, few male-female differences were observed in the probability of making a transition into drug use, once an opportunity had occurred. CONCLUSIONS: Previously documented male excess in rates of drug use may be due to greater male exposure to opportunities to try drugs, rather than to greater chance of progressing from initial opportunity to actual use. This suggests that sex differences in drug involvement emerge early in the process. Implications of these findings are discussed in relation to the epidemiology and prevention of drug use, and future research on sex differences in drug involvement.

Adolescent↗
PubMed1999

Leucine supplementation enhances skeletal muscle recovery in rats following exercise.

This study was designed to determine the ability of leucine to enhance muscle recovery after exercise. Male rats (200 g) were divided into five groups: sedentary, food-deprived (SF); exercised, food-deprived (EF); exercised, fed a carbohydrate meal (EC); exercised, fed a leucine meal (EL); and exercised, fed a combination of carbohydrate and leucine (ECL). All meals were administered by oral gavage immediately following exercise. EC and ECL meals were isocaloric and provided 15% of daily energy intake. EL and ECL meals each provided 270 mg leucine. Rats ran on a motor-driven treadmill for 2 h at 36 m/min and were killed 1 h postexercise. Plasma glucose and insulin were measured, and the gastrocnemius and plantaris muscles were excised as a unit to determine glycogen levels and the fractional rate of skeletal muscle protein synthesis (Ks). Exercise did not alter plasma glucose or insulin. In contrast, prolonged exercise reduced muscle glycogen (-51%) and Ks (-18%). Refeeding a combination of carbohydrate and leucine increased plasma insulin relative to the EF and SF groups and produced complete recovery of muscle Ks and glycogen to values not different from those in SF rats. Feeding leucine alone restored Ks to that in the SF group without affecting plasma glucose or insulin concentrations. Feeding carbohydrate alone enhanced the rate of glycogen repletion compared to the EF group, concomitant with increases in plasma glucose and insulin. The degree of glycogen recovery correlated with plasma insulin concentrations (r = 0.58, P < 0.05). These data suggest that leucine stimulates muscle protein synthesis following exercise, independent of increased plasma insulin. This is the first demonstration that orally administered leucine stimulates recovery of skeletal muscle protein synthesis after exercise.

Animals↗
PubMed1999

Enhanced cognitive performance with estrogen use in nondemented community-dwelling older women.

OBJECTIVE: To examine the association between history of postmenopausal estrogen use and cognitive function in a large sample of nondemented community-dwelling older women. SETTING: A community of older residents in Cache County, Utah. PARTICIPANTS: A total of 2338 nondemented women aged 65 and older. MEASUREMENTS: All subjects were administered the Modified Mini-Mental State Examination (3MSE). Self-reported information on current and past use of estrogen after menopause was also obtained using a structured interview. Estrogen use was trichotomized as: no use, past use, and current use. Apolipoprotein E (APOE) genotype was determined and was dichotomized by the presence of an epsilon4 allele. A series of variance/covariance models was conducted with the 3MSE score as the dependent variable, first considering estrogen use alone, then adding, sequentially as covariates, education, age, health status, APOE genotype, current depression status, and history of head injury. RESULTS: In the simplest bivariate model, the 3MSE means (and confidence intervals) were 92.1 (91.7-92.4), 93.5 (93.1-93.9), and 94.4 (94.0-94.7) for never-, past-, and current users, respectively. In the final model (R2 = 0.28), no use of estrogen replacement therapy (P = .006), lower education (P < .001), poorer perceived health status (P = .035), current depression (P = .014), and presence of at least one APOE epsilon4 allele (P < .001) each independently predicted lower 3MSE score. Both current and past estrogen users had significantly higher 3MSE scores than never-users (P = .0063 and P = .0096, respectively). CONCLUSIONS: In this large community study, women who had used estrogen after menopause scored higher on the 3MSE. This finding remained, even after controlling for the effects of age, education, APOE genotype, and other variables that may affect cognition. These data support studies reporting a beneficial role of estrogen on cognition in postmenopausal women, particularly among current estrogen users.

Aged↗
PubMed1999

Cognitive decline in adulthood: an 11.5-year follow-up of the Baltimore Epidemiologic Catchment Area study.

OBJECTIVE: The epidemiology of cognitive decline over 11.5 years was investigated in a large community-residing population, with a special emphasis on the relationship between education and cognitive decline. METHOD: The study was an 11.5-year follow-up of a probability sample of the adult household residents of east Baltimore. From the Baltimore cohort of the Epidemiologic Catchment Area study, 1,488 participants completed the Mini-Mental State during three study waves in 1981, 1982, and 1993-1996. For each study participant, the difference in scores on the Mini-Mental State between waves 2 and 3 was calculated. RESULTS: Over a median interval of 11.5 years, the study participants' scores on the Mini-Mental State declined a mean of 1.41 points, and the scores of 68% of the participants declined by at least 1 Mini-Mental State point. With and without adjustment for age, greater declines were associated with having 8 years or less of formal education and with being African American. CONCLUSIONS: Over a long time period, cognitive decline occurred in all age groups. Having more than 8 years of formal education was associated with less decline. However, beyond 9 years, additional education was not associated with a further reduction in cognitive decline. This suggests that a minimal amount of education during early critical periods might confer protection against cognitive decline later in life.

Adolescent↗
PubMed1999

Panic attacks and suicide attempts in mid-adolescence.

OBJECTIVE: The aim of this study was to investigate the association of panic attacks and suicide attempts in a community-based sample of 13-14-year-old adolescents. METHOD: The data are from a survey of 1,580 students in an urban public school system located in the mid-Atlantic region of the United States. Logistic regression methods were used to estimate associations between panic attacks and suicidal ideation and suicide attempts. RESULTS: Controlling for demographic factors, major depression, the use of alcohol, and the use of illicit drugs, the authors found that adolescents with panic attacks were three times more likely to have expressed suicidal ideation and approximately two times more likely to have made suicide attempts than were adolescents without panic attacks. CONCLUSIONS: This new epidemiologic research adds to the evidence of an association between panic attacks and suicide attempts during the middle years of adolescence.

Adolescent↗
PubMed1999

Physician substance use by medical specialty.

Self-reported past year use of alcohol, tobacco, marijuana, cocaine, and two controlled prescription substances (opiates, benzodiazepines); and self-reported lifetime substance abuse or dependence was estimated and compared for 12 specialties among 5,426 physicians participating in an anonymous mailed survey. Logistic regression models controlled for demographic and other characteristics that might explain observed specialty differences. Emergency medicine physicians used more illicit drugs. Psychiatrists used more benzodiazepines. Comparatively, pediatricians had overall low rates of use, as did surgeons, except for tobacco smoking. Anesthesiologists had higher use only for major opiates. Self-reported substance abuse and dependence were at highest levels among psychiatrists and emergency physicians, and lowest among surgeons. With evidence from studies such as this one, a specialty can organize prevention programs to address patterns of substance use specific to that specialty, the specialty characteristics of its members, and their unique practice environments that may contribute risk of substance abuse and dependence.

Adult↗
PubMed1999

Estimated occurrence of tobacco, alcohol, and other drug use among 12- to 18-year-old students in Panama: results of Panama's 1996 National Youth Survey on Alcohol and Drug Use.

This report provides the first epidemiological evidence on tobacco, alcohol, and other drug use among school students in Panama, using data from a student survey completed in 1996. Specifically, we examine sex, age, grade level, type of school, and urban-rural variations in the occurrence of tobacco, alcohol, and other drug use. Estimates of lifetime prevalence and past-year use of these products were obtained using data from Panama's 1996 National Youth Survey on Alcohol and Drug Use (n = 6,477). To account for the multistage sampling design of the survey, all estimates and respective standard errors are derived by the Taylor series approximation method using Epi Info 6.0 CSAMPLE software. In general, more males, more older students, and more students in higher grades have used licit and illicit drugs, even though male-female differences tend to be small. Public-private school differences and urban-rural trends vary depending on the drug. The findings of this study are discussed in relation to the epidemiology and prevention of drug use in Panama. Based on these data, we seek to provide information to be used by the Government of Panama in its planning for prevention programs directed toward students in Panamanian schools.

Adolescent↗
PubMed1999

Tobacco smoking and depressed mood in late childhood and early adolescence.

OBJECTIVES: This study builds on previous observations about a suspected causal association linking tobacco smoking with depression. With prospective data, the study sheds new light on the temporal sequencing of tobacco smoking and depressed mood in late childhood and early adolescence. METHODS: The epidemiologic sample that was studied consisted of 1731 youths (aged 8-9 to 13-14 years) attending public schools in a mid-Atlantic metropolitan area, who were assessed at least twice from 1989 to 1994. A survival analysis was used to examine the temporal relationship from antecedent tobacco smoking to subsequent onset of depressed mood, as well as from antecedent depressed mood to subsequent initiation of tobacco use. RESULTS: Tobacco smoking signaled a modestly increased risk for the subsequent onset of depressed mood, but antecedent depressed mood was not associated with a later risk of starting to smoke tobacco cigarettes. CONCLUSIONS: This evidence is consistent with a possible causal link from tobacco smoking to later depressed mood in late childhood and early adolescence, but not vice versa.

Adolescent↗
PubMed1999

First opportunities to try drugs and the transition to first drug use: evidence from a national school survey in Panama.

In recent evidence from the United States, there generally are no male-female differences in the probability of drug use among persons who report an opportunity to try the drugs. This is an important observation that might help us understand male-female differences in later drug use and dependence, but the observation needs to be replicated elsewhere. We begin this replication process using data from a 1996 national school survey of drug involvement among 6,477 students age 12-18 in Panama. We first examine the occurrence of an opportunity to use drugs by grade. We then follow these analyses with an examination of male-female differences in drug opportunity patterns. We found opportunities to use drugs and actual drug use to be greater at higher grade levels. Also, we found the probability of making a transition to use, given an opportunity, to be more likely among upper-grade students. Consistent with results observed in the United States, we found males in Panama to be more likely to have an opportunity to use marijuana, crack-cocaine, and other forms of cocaine, but not more likely than females to make a transition into drug use once an opportunity had occurred to try each drug. These findings are discussed in relation to the epidemiology and prevention of drug use in Panama and elsewhere, and future research on male-female differences in drug involvement.

Adolescent↗
PubMed1999

Tobacco smoking and other suspected antecedents of nonmedical psychostimulant use in the United States, 1995.

This study investigates the extent to which tobacco smoking is associated with the nonmedical use of psychostimulants and the temporal order of the age of first use for tobacco and psychostimulants within a nationally representative sample of United States household residents. At the same time, alcohol use and other suspected determinants of psychostimulant use are investigated and held constant, using multiple regression models. Data were taken from public use files of the 1995 National Household Survey on Drug Abuse. Conditional logistic regression analyses were performed to derive estimated relative odds of using stimulants for tobacco smokers versus nonsmokers, holding constant other potentially distorting influences. This study provides recent evidence on tobacco smoking as one of the potentially malleable risk factors for the nonmedical use of stimulant drugs.

Adolescent↗