Biomedical subjects

Aaron Cohen

Publications and source records attributed to Aaron Cohen.

15 recordsLinked to original sources

PubMed2006

Closure of a home hospital program: impact on hospitalization rates.

Home hospitalization (HH), as a substitute to in-patient care, is an area of growing interest, particularly amongst the elderly. Debate nonetheless exists concerning its economic justification. This study describes a natural experiment that arose following spending cuts and closure of the 400 patient Jerusalem HH program. It examines the hypothesis that HH closure would cause increasing geriatric and general medical hospital utilization amongst the 45,000 beneficiaries of the Jerusalem Clalit Health Fund (HMO) aged 65 years and over. Hospitalization rates were measured prior to and following HH closure, and analysis of variance confirmed the significance of the differences in both geriatric (p<0.0001) and general medical hospitalization rates (p=0.02) over the study period. Linear regression analyses of the hospitalization rates prior to HH closure were performed to determine the expected trajectory of hospitalization rates following HH closure. The observed hospital utilization in the year following HH closure cost 6.2 million US dollars in excess of predicted expenditure; closure of the HH resulted in the saving of 1.3 million USdollars. The ratio of direct increased costs to savings was 5:1 thus confirming the hypothesis that HH closure would result in increased hospital utilization rates among the local elderly population.

Aged↗

PubMed2006

Exposure to diesel and gasoline engine emissions and the risk of lung cancer.

Pollution from motor vehicles constitutes a major environmental health problem. The present paper describes associations between diesel and gasoline engine emissions and lung cancer, as evidenced in a 1979-1985 population-based case-control study in Montreal, Canada. Cases were 857 male lung cancer patients. Controls were 533 population controls and 1,349 patients with other cancer types. Subjects were interviewed to obtain a detailed lifetime job history and relevant data on potential confounders. Industrial hygienists translated each job description into indices of exposure to several agents, including engine emissions. There was no evidence of excess risks of lung cancer with exposure to gasoline exhaust. For diesel engine emissions, results differed by control group. When cancer controls were considered, there was no excess risk. When population controls were studied, the odds ratios, after adjustments for potential confounders, were 1.2 (95% confidence interval: 0.8, 1.8) for any exposure and 1.6 (95% confidence interval: 0.9, 2.8) for substantial exposure. Confidence intervals between risk estimates derived from the two control groups overlapped considerably. These results provide some limited support for the hypothesis of an excess lung cancer risk due to diesel exhaust but no support for an increase in risk due to gasoline exhaust.

Adult↗

PubMed2006

Chronic back pain among the elderly: prevalence, associations, and predictors.

STUDY DESIGN: A longitudinal age homogeneous cohort study. OBJECTIVE: To describe the prevalence, nature, and predictors of chronic back pain (CBP) in older people. SUMMARY OF BACKGROUND DATA: CBP is a growing source of morbidity among the elderly. Few longitudinal studies exist, and its time course and predictors are largely undefined. METHODS: The Jerusalem Longitudinal Study assessed 277 subjects aged 70 years at baseline and 77 years at follow-up. Data collection included back pain symptoms, psychosocial, functional, and physical domains. RESULTS: The prevalence of CBP increased from 44% to 58% at ages 70 and 77 years, respectively, while frequency and severity decreased. CBP was associated with female gender, economic difficulties, loneliness, fatigue, poor self-rated health, dependence in activities of daily living, joint pain, and obesity. Depression was associated at age 70 years, and unemployment, not leaving the house for leisure, poor sleep satisfaction, hypertension, and osteoporosis were at age 77 years. Predictors of CBP at age 77 years were female gender, loneliness, joint pain, hypertension, and preexisting CBP. Unemployment and not leaving the house for leisure showed a trend toward significance. CONCLUSION: CBP is increasingly common in the elderly. Psychosocial factors, female gender, hypertension, and existing joint pain identify individuals most at risk.

Age Factors↗

PubMed2006

Toward guidelines for the ethical reanalysis and reinterpretation of another's research.

Reanalysis and reinterpretation occur when a person other than the original investigator obtains an epidemiologic data set and conducts analyses to evaluate the quality, reliability or validity of the dataset, methods, results or conclusions reported by the original investigator. We propose ethical guidelines with regard to the duty of original investigators to cooperate with competent impartial reanalysis and for the sponsors of reanalysis and reinterpretation and the epidemiologists who carry it out. The rights and interests of these parties and of the public interest need to be protected.

Cooperative Behavior↗

PubMed2006

Global sleep satisfaction of older people: the Jerusalem Cohort Study.

OBJECTIVES: To describe the nature of global sleep satisfaction (GSS) of older people and the factors associated with it. DESIGN: A 7-year follow-up of an age-homogenous cohort. SETTING: Community based. PARTICIPANTS: Two hundred ninety subjects aged 70 at baseline and 77 at follow-up. MEASUREMENTS: Self-reported sleep domains and a comprehensive assessment of health variables, including psychosocial, physical, and functional factors, at ages 70 and 77. RESULTS: GSS was found to be poor in 25% of subjects at ages 70 and 77, with an estimated average annual remission rate of 7% and an annual incidence of 2.4%. Poor GSS at ages 70 and 77 was significantly associated with difficulty falling asleep, awakening feeling tired, two or more nocturnal awakenings, and taking sleeping tablets. Significant cross-sectional associations were found at age 70 and 77 between poor GSS and poor self-rated health, general fatigue, depression, dependence in one or more activities of daily living, and low level of physical activity. In a regression analysis, risk factors at age 70 for subsequent poor GSS were loneliness, depression, poor self-rated health, economic difficulties, back pain, obesity, and prior poor GSS. The only significant long-term association was between poor GSS and poor self-rated health. GSS did not influence mortality data. CONCLUSION: Poor GSS in older people is common and chronic. Its chief determinants are loneliness, depression, poor self-rated health, economic difficulties, back pain, and obesity. It predicts poor self-rated health but not increased mortality.

Age Factors↗

PubMed2005

The impact of visual impairment on health, function and mortality.

BACKGROUND AND AIMS: Our aim was to determine the impact of visual impairment on self-rated health, function and mortality amongst a community-dwelling elderly cohort. METHODS: The study design was prospective and longitudinal, subjects being taken from an age-homogeneous, community-dwelling cohort comprising 452 subjects aged 70 in 1990 and 839 subjects aged 77 in 1998. Comprehensive data were collected by structured interviews and medical examinations carried out during home visits. Data included each subject's demographic and socio-economic profile, medical history, physical findings, functional status and self-rated health status. Visual acuity was measured using a Snellen chart and visual impairment was defined as best-eye corrected visual acuity of 20/40 or worse on Snellen chart testing. RESULTS: Measured and self-reported visual impairment correlated closely, and were significantly more prevalent amongst subjects with low education and poor financial status. Visually impaired subjects showed significantly greater dependence in ADL and IADL, poor self-rated health, less ability to rely on friends, increased loneliness and, in men aged 77, increased visits to the emergency room and hospital admissions. Visual impairment at age 70 significantly predicted poor self-rated health (p=0.029, OR 2.36, 95% CI 1.09-5.10), dependence in ADL (p=0.007, OR 2.91, 95% CI 1.34-6.33), general tiredness (p=0.037, OR 2.40, 95% CI 1.06-5.44), and mortality, with a two-and-a-half-fold increase in risk of death at seven years (p=0.0017,OR 2.84, 95% CI 1.48-5.46). CONCLUSIONS: Visual impairment in the elderly increases the risk of social, functional and medical decline.

Aged↗

PubMed2005

Working late: the impact of work after 70 on longevity, health and function.

BACKGROUND AND AIMS: Although many older persons choose to postpone retirement, the health consequences of this decision are still debated. This study aimed at determining the impact of continued employment on life-style, well-being, health and survival in a cohort of community-dwelling 70-year-olds. METHODS: A longitudinal study of a homogeneously aged cohort was conducted in two stages. Data from extensive interviews, physical examinations and clinical laboratory information were obtained from west Jerusalem residents born in 1920-1 through home-based examinations. In 1990-1, 162 women and 218 men were examined, at age 70, and in 1997-8, 390 women and 398 men at age 77. Two hundred and thirty one subjects participated in both study stages and were available for longitudinal analysis. For each subject at each study stage, a comprehensive profile detailed social characteristics, including life-style and personal functions, and medical status including illnesses and use of medical services. At each stage, employed subjects were compared with those who neither worked for compensation nor as volunteers. Logistic regression compared health outcomes at age 77 for subjects who worked at age 70 with those of subjects who had not. RESULTS: At age 70, 37 women and 98 men were gainfully employed, whereas 125 women and 120 men did not work. At age 77, wage-earners numbered 26 women and 95 men, and non-workers 364 women and 303 men. In the cross-sectional analyses at ages 70 and 77, work correlated with better perceived health and greater independence for both women and men. Independent of pre-existing economic difficulties, education, illnesses, functional dependence and self-assessed health, workers at age 70 after seven years were in better health (OR 2.12, 95% CI 1.04, 4.30), had more ADL independence, (OR 2.60, 95% CI 1.08, 6.29) and increased survival rates (OR 2.13, 95% CI 1.06, 4.28). CONCLUSIONS: Independent of baseline status, working at age 70 correlates with health, self-sufficiency and longevity.

Activities of Daily Living↗

PubMed2005

Strategies to enhance longevity and independent function: the Jerusalem Longitudinal Study.

PURPOSE: To analyze the impact of medical and social factors on survival and function from age 70 to 82 and point to possible genetic basis for differences. MATERIALS AND METHODS: Longitudinal, cohort study of a representative sample of Jerusalem residents, born 1920-1921. At age 70, 463 subjects underwent a thorough interview eliciting social determinants as well as a medical history and examination and laboratory investigation. At age 77,265 of the survivors, 71%, were re-examined. In 2002, all death certificates in Israel were reviewed. End points were performance of basic and advanced tasks with ease at age 77 and survival to age 82 or life span in subjects who had succumbed. The independent influence of each factor was tested using logistic regression. RESULTS: 89.6% of women were alive after 6 years and 77.4% after 12. Survival for men was 79.9% and 59.8%, respectively. Social factors predominated in the correlation with longer life: financial security, p=.0004; volunteer activity, p=.0002; regular exercise, p=.0002; positive self-assessed health, p<.0001; and activities of daily living (ADL) independence, p<.0001. Less striking but significant correlation for longevity was noted for avoiding naps, p=.04 and instrumental activities of daily living (IADL) independence, p=.048. Medical conditions associated with increased mortality included diabetes, p<.0001; coronary artery disease, p=.0002; impaired vision, p=.0007; and renal insufficiency, p=.008. Anemia and disturbed sleep did not independently correlate with mortality while the association with hypertension did not reach statistical significance, p=.056. In a regression to determine the independent impact of medical and social factors on mortality, unimpaired renal function, good vision, avoiding afternoon naps, volunteer or compensated work, physical activity and IADL independence all correlated with improved survival. Moreover, good vision, volunteer work or work for pay and physical activity were independently associated with continued ADL independence after 7 years. CONCLUSIONS: These findings highlight the ability of social, economic and functional factors to modify genetic influence on survival and function. Increased physical and social activity is an important tool to lengthen the span of robust function. The role of heredity in determining function and mortality may be expressed through diverse pathways.

Activities of Daily Living↗

PubMed2005

Candidate genes associated with ageing and life expectancy in the Jerusalem longitudinal study.

In an exploratory study, 11 common polymorphisms were examined for contributing to longevity including: apolipoprotein E (apoE), methylenetetrahydrofolate reductase (MTHFR), cathepsin D (CAD), superoxide dismutase 2 (SOD2), angiotensinogen (AGT) and insulin-like growth factor 2 (IGF2), Leiden factor 7, p53 oncogene, dopamine D4 receptor (DRD4) and the serotonin transporter (SERT). Genotype and allele frequencies of these genes were compared in 224 older (75 years) Jewish Jerusalem residents of Ashkenazi ethnicity to a group of 441 younger subjects (22 years). Nominally significant results provide suggestive evidence in the Ashkenazi group that apoE, MHTFR, SOD2, IGF2 ApaI, and factor VII are risk factors for a single outcome, survival to 75. Overall, the more genetically homogenous Ashkenazi ethnic group showed evidence for association in five genes examined suggesting that future studies in this population would gainfully focus on this ethnic group.

Adolescent↗

PubMed2003

On the relationship between time-series studies, dynamic population studies, and estimating loss of life due to short-term exposure to environmental risks.

There is a growing concern that short-term exposure to combustion-related air pollution is associated with increased risk of death. This finding is based largely on time-series studies that estimate associations between daily variations in ambient air pollution concentrations and in the number of nonaccidental deaths within a community. Because these results are not based on cohort or dynamic population designs, where individuals are followed in time, it has been suggested that estimates of effect from these time-series studies cannot be used to determine the amount of life lost because of short-term exposures. We show that results from time-series studies are equivalent to estimates obtained from a dynamic population when each individual's survival experience can be summarized as the daily number of deaths. This occurs when the following conditions are satisfied: a) the environmental covariates vary in time and not between individuals; b) on any given day, the probability of death is small; c) on any given day and after adjusting for known risk factors for mortality such age, sex, smoking habits, and environmental exposures, each subject of the at-risk population has the same probability of death; d) environmental covariates have a common effect on mortality of all members of at-risk population; and e) the averages of individual risk factors, such as smoking habits, over the at-risk population vary smoothly with time. Under these conditions, the association between temporal variation in the environmental covariates and the survival experience of members of the dynamic population can be estimated by regressing the daily number of deaths on the daily value of the environmental covariates, as is done in time-series mortality studies. Issues in extrapolating risk estimates based on time-series studies in one population to estimate the amount of life lost in another population are also discussed.

Air Pollutants↗

PubMed2002

Antibody levels against galactosyl (alpha1 --> 3) galactose epitopes in cervical mucus from patients with human papillomavirus infection.

OBJECTIVES: The general objective of the present study is to quantify antigalactosyl (alpha1 --> 3) galactose (anti-Gal) antibody levels in the cervical mucus of patients with/without human papillomavirus (HPV) infection and, as specific objectives, to compare these levels in the different HPV subgroups and with the presence of intraepithelial lesions. METHODS: Sixty women between 18 and 35 years old (mean: 26 years) were studied through the following methods: vaginal cytology, colposcopy, biopsy of suspicious lesions, sample taking for evaluating HPV presence through PCR and hybridization, and quantification of anti-Gal levels using ELISA with laminin antigen extracted from the Engelbreth-Horm-Swarm cell line. RESULTS: The presence of HPV was detected in 55% of patients; 45% of them had intermediate/high oncogenic risk HPV, 12% had low oncogenic risk HPV, and the other 43% had both subgroups. There were significantly higher anti-Gal levels in the HPV+ group when compared with the HPV- group (P < 0.0001); also, when dividing the HPV+ group into one subgroup with normal cytology and another with cervical intraepithelial neoplasia (CIN) 1, we found higher values in the latter group (P < 0.0001). There was no significant difference in anti-Gal levels in the various HPV subgroups. CONCLUSION: High anti-Gal levels are found in the cervical mucus of patients with HPV infection and CIN 1, which suggests the participation of local humoral immunity in cervical lesions.

Adolescent↗

PubMed2002

Effect of exercise on ease in performing activities of daily living and instrumental activities of daily living from age 70 to 77: the Jerusalem longitudinal study.

OBJECTIVES: To determine the prevalence of independence and ease of performance in activities of daily living (ADLs) and instrumental activities of daily living (IADLs) at ages 70 and 77 in a well-characterized cohort and to measure the effect of regular exercise at age 70 on independence and ease of performance 7 years later. DESIGN: Two stages of a longitudinal study of an age-homogeneous cohort employing extensive interview data, physical examination, and clinical laboratory investigation. SETTING: Home-based interviews and examinations in Jerusalem. PARTICIPANTS: Two hundred eighty-seven west Jerusalem residents, born between June 1920 and May 1921, who participated fully in two phases of an ongoing longitudinal cohort study. Subjects were culled from a larger study population of 605 in the first phase and 1,021 in the second phase. MEASUREMENTS: Two-stage comprehensive demographic, social, and economic profile; medical history and examination; cognitive and affective assessment; and clinical laboratory studies performed in 1990-91 and 1997-98. The investigation questionnaire included details of ADL and IADLs and voluntary exercise. RESULTS: Most aspects of personal and social life did not change from age 70 to 77. Independence in ADLs remained high, as did self-reliance in IADLs for women. A more-sensitive marker of diminished function was reported ease in performance, which declined for use of the toilet, dressing, and all spheres of IADLs. For nearly every task, subjects who reported exercising 4 days a week at age 70 were more likely to report ease in performance at age 77. In a logistic regression accounting for the presence of diabetes mellitus, hypertension, obesity, chronic back pain, loneliness, and performance with ease at age 70 and deterioration in self-assessed health from age 70 to 77, ease of performance in at least three of four ADL tasks was independently related to exercise at age 70 for women (odds ratio (OR) = 8.5, 95% confidence interval (CI) = 2.0-36.2) and for men (OR = 4.3, 95% CI = 1.1-17.1). Ease of independent function in at least four of five IADL tasks also correlated to exercise for men in this regression (OR = 3.7, 95% CI = 1.1-12.2) but not for women (OR = 2.0, 95% CI = 0.6-6.3). Ease in shopping, alternatively, correlated with physical activity for men (OR = 4.3, 95% CI = 1.5-12.0) and women (OR = 2.6, 95% CI = 1.1-6.1). CONCLUSIONS: Subjects remained active and independent at age 77. Reported ease of performance declined and revealed changes in function. Exercise at least four times a week at age 70 preserved ease of performance at age 77 independent of the influence of specific disease or general self-assessed health.

Activities of Daily Living↗

PubMed2002

International expert workshop on the analysis of the economic and public health impacts of air pollution: workshop summary.

Forty-nine experts from 18 industrial and developing countries met on 6 September 2001 in Garmisch-Partenkirchen, Germany, to discuss the economic and public health impacts of air pollution, particularly with respect to assessing the public health benefits from technologies and policies that reduce greenhouse gas (GHG) emissions. Such measures would provide immediate public health benefits, such as reduced premature mortality and chronic morbidity, through improved local air quality. These mitigation strategies also allow long-term goals--for example, reducing the buildup of GHG emissions--to be achieved alongside short-term aims, such as immediate improvements in air quality, and therefore benefits to public health. The workshop aimed to foster research partnerships by improving collaboration and communication among various agencies and researchers; providing a forum for presentations by sponsoring agencies and researchers regarding research efforts and agency activities; identifying key issues, knowledge gaps, methodological shortcomings, and research needs; and recommending activities and initiatives for research, collaboration, and communication. This workshop summary briefly describes presentations made by workshop participants and the conclusions of three separate working groups: economics, benefits transfer, and policy; indoor air quality issues and susceptible populations; and development and transfer of dose-response relationships and exposure models in developing countries. Several common themes emerged from the working group sessions and subsequent discussion. Key recommendations include the need for improved communication and extended collaboration, guidance and support for researchers, advances in methods, and resource support for data collection, assessment, and research.

Air Pollutants↗

PubMed2002

An empirical examination among Canadian teachers of determinants of the need for employees' assistance programs.

The goal of this study was to propose and test a model of the determinants of the need for employees' assistance programs. The research model proposed six independent variables related to employees' assistance programs: organizational support, personal coping, negative spillover, occupational commitment, job satisfaction, and tenure. The model proposed that the relationship between the independent variables and the need for employees' assistance programs was not direct but was mediated by work-nonwork conflict and job stress. Questionnaires were mailed to employees of a school district in western Canada, and 300 usable questionnaires were returned, a response rate of 42%. The research model received modest support from the data. Some of the fit indices were not as strong as expected. On the other hand, the conceptual model was supported.

Adaptation, Psychological↗

PubMedDate not supplied

Home hospitalization.

CONTEXT: Home Hospital is a worldwide phenomenon that provides acute and subacute medical care in the home in an attempt to reduce the need for hospitalization. OBJECTIVE: To evaluate the clinical parameters of a home hospitalization program operating in Jerusalem for 8 years. DESIGN: The Jerusalem Home Hospitalization (HH) program admits inpatients for early discharge from the hospital or accepts patients from the community when hospitalization is imminent. A clinical profile of HH was obtained from a chart review. OUTCOME MEASURES: Demographic data, diagnoses, duration of HH and the nature of the care required by patients at the end of HH were surveyed in 1995. RESULTS: From November 1991 until the end of 1999, 6297 patients over age 65 were admitted to HH. As reflected in 1995 data, the most common disease categories in HH were heart disease, malignancy and infection; 51% of HH lasted less than one month, 69% less than two. CONCLUSION: For 8 years, HH in Jerusalem has provided intensive home care with high levels of patient and family satisfaction.

Journal Article↗