Hal Morgenstern

Uses of ecologic analysis in epidemiologic research.

Despite the widespread use of ecologic analysis in epidemiologic research and health planning, little attention has been given by health scientists and practitioners to the methodological aspects of this approach. This paper reviews the major types of ecologic study designs, the analytic methods appropriate for each, the limitations of ecologic data for making causal inferences and what can be done to minimize these problems, and the relative advantages of ecologic analysis. Numerous examples are provided to illustrate the important principles and methods. A careful distinction is made between ecologic studies that generate or test etiologic hypotheses and those that evaluate the impact of intervention programs or policies (given adequate knowledge of disease etiology). Failure to recognize this difference in the conduct of ecologic studies can lead to results that are not very informative or that are misinterpreted by others.

Inappropriate Medication Prescribing in Skilled-Nursing Facilities

OBJECTIVE To quantify the appropriateness of medication prescriptions in nursing home residents. DESIGN Prospective, cohort study. SETTING Twelve nursing homes in the greater Los Angeles area. PARTICIPANTS A total of 1106 nursing home residents. MAIN OUTCOME MEASURES The appropriateness of medication prescriptions was evaluated using explicit criteria developed through consensus by 13 experts from the United States and Canada. These experts identified 19 drugs that should generally be avoided and 11 doses, frequencies, or durations of use of specific drugs that generally should not be exceeded. RESULTS Based on the consensus criteria, 40% of residents received at least one inappropriate medication order, and 10% received two or more inappropriate medication orders concurrently; 7% of all prescriptions were inappropriate. Physicians prescribed a greater number of inappropriate medications for female residents. Regression analysis, corrected for clustering effects within facilities, showed that a greater number of inappropriate medication prescriptions were ordered in larger nursing homes. Inappropriate prescriptions were not related to the proportion of Medicaid (Medi-Cal) residents or the number of physicians practicing in the homes. CONCLUSIONS Inappropriate medication prescribing in nursing homes is common. Female residents and residents of large nursing homes are at the greatest risk for receiving an inappropriate prescription.

Strengthening the Reporting of Observational Studies in Epidemiology (STROBE)

Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research.

Heterogeneity of childhood asthma among hispanic children : Puerto rican children bear a disproportionate burden

OBJECTIVES. To estimate differences in asthma prevalence among Hispanic subgroups and non-Hispanic children living in the United States and to explore the association between these differences and risk factors. METHODS. Weighted logistic regression analyses of merged 1997 to 2001 National Health Interview Survey data were used to estimate the prevalence of asthma diagnosis and asthma attacks in a sample of 46511 children (age: 2–17 years) living in the 50 states and the District of Columbia. RESULTS. Puerto Rican children had the highest prevalence of lifetime asthma (26%) and recent asthma attacks (12%), compared with non-Hispanic black children (16% and 7%, respectively), non-Hispanic white children (13% and 6%, respectively), and Mexican children (10% and 4%, respectively). Adjustment for asthma risk factors did not change these comparisons appreciably. Compared with non-Hispanic white children, the adjusted odds ratios (ORs) for a lifetime asthma diagnosis were 2.33 (95% confidence interval [CI]: 1.90–2.84) for Puerto Rican children, 1.16 (95% CI: 1.04–1.29) for non-Hispanic black children, and 0.90 (95% CI: 0.79–1.03) for Mexican children. Birthplace influenced the association between ethnicity and lifetime asthma diagnosis differently for Puerto Rican and Mexican children. Compared with United States-born non-Hispanic white children with United States-born parents, the adjusted ORs were 1.95 (95% CI: 1.48–2.57) for Puerto Rican children in families with the child and parent(s) born in the 50 states/District of Columbia and 2.50 (95% CI: 1.51–4.13) for island-born Puerto Rican children with island-born parents. The corresponding adjusted ORs for Mexican children were 1.05 (95% CI: 0.90–1.22) for families born in the 50 states/District of Columbia and 0.43 (95% CI: 0.29–0.64) for those born in Mexico. The results were similar for recent asthma attacks. CONCLUSIONS. The appreciably higher asthma morbidity rates experienced by Puerto Rican children cannot be explained by sociodemographic and other risk factors measured in the National Health Interview Survey. The heterogeneity of asthma among Hispanic subgroups should be considered in developing effective public health prevention and intervention strategies.

Women, myocardial infarction, and dementia in the very old

Dementia is a major public health problem among the very old. Available information on incidence and prevalence is sparse and variable; however, there appears to be a higher prevalence among very old women. We present data from a prospective study of initially nondemented community-residing elderly. There were 75 incident dementia cases (up to 7 years of follow-up) of which at least 47% were probable Alzheimers disease. Based on a proportional hazards analysis, women were over 3 times more likely to develop dementia than men despite controlling for baseline demographic, psychosocial, and medical history variables. Poor word fluency and a high normal Blessed test score at baseline were also strong predictors of dementia. We did not find age, head trauma, thyroid disease, or family history of dementia to be risk factors. A new finding is that history of myocardial infarction (MI) is associated with dementia, such that women with a history of MI were 5 times more prone to dementia than those without a history. This observation was not true for men.

Risk factors for penile cancer: results of a population-based case-control study in Los Angeles County (United States).

The etiology of penile cancer is poorly understood, with neonatal circumcision being one of the few recognized nondemographic risk factors. Multiple logistic regression was used to analyze interview data from 100 matched case–control pairs; cases of carcinoma in situ (CIS) and invasive carcinoma of the penis were analyzed separately as well as together. Phimosis was strongly associated with invasive carcinoma (adjusted odds ratio [OR] = 16; 95% confidence interval [CI] = 4.5–57) but not CIS (OR = 1.7; 95% CI = 0.32–7.8), and these associations persisted when the analyses were restricted to uncircumcised subjects. Neonatal circumcision was inversely associated with invasive carcinoma (OR = 0.41; 95% CI = 0.13–1.1) but not CIS, and the observed association with invasive carcinoma was weakened appreciably when the analysis was restricted to subjects with no history of phimosis (OR = 0.79; 95% CI = 0.29–2.6). Other factors positively associated with invasive carcinoma or CIS or both were injury to the penis, cigarette smoking, physical inactivity and, to a lesser extent, genital warts and other infections or inflammation of the penis. Conclusions: Although many effects were imprecisely estimated in this study, the protective effect of circumcision on invasive penile cancer appears to be mediated in large part by phimosis; furthermore, the effects of certain factors such as phimosis and circumcision appear to differ for CIS and invasive carcinoma.

A Randomized Trial of Chiropractic Manipulation and Mobilization for Patients With Neck Pain: Clinical Outcomes From the UCLA Neck-Pain Study

OBJECTIVES This study compared the relative effectiveness of cervical spine manipulation and mobilization for neck pain. METHODS Neck-pain patients were randomized to the following conditions: manipulation with or without heat, manipulation with or without electrical muscle stimulation, mobilization with or without heat, and mobilization with or without electrical muscle stimulation. RESULTS Of 960 eligible patients, 336 enrolled in the study. Mean reductions in pain and disability were similar in the manipulation and mobilization groups through 6 months. CONCLUSIONS Cervical spine manipulation and mobilization yield comparable clinical outcomes.

Marijuana Use and the Risk of Lung and Upper Aerodigestive Tract Cancers: Results of a Population-Based Case-Control Study

Background: Despite several lines of evidence suggesting the biological plausibility of marijuana being carcinogenic, epidemiologic findings are inconsistent. We conducted a population-based case-control study of the association between marijuana use and the risk of lung and upper aerodigestive tract cancers in Los Angeles. Methods: Our study included 1,212 incident cancer cases and 1,040 cancer-free controls matched to cases on age, gender, and neighborhood. Subjects were interviewed with a standardized questionnaire. The cumulative use of marijuana was expressed in joint-years, where 1 joint-year is equivalent to smoking one joint per day for 1 year. Results: Although using marijuana for ≥30 joint-years was positively associated in the crude analyses with each cancer type (except pharyngeal cancer), no positive associations were observed when adjusting for several confounders including cigarette smoking. The adjusted odds ratio estimate (and 95% confidence limits) for ≥60 versus 0 joint-years was 1.1 (0.56, 2.1) for oral cancer, 0.84 (0.28, 2.5) for laryngeal cancer, and 0.62 (0.32, 1.2) for lung cancer; the adjusted odds ratio estimate for ≥30 versus 0 joint-years was 0.57 (0.20, 1.6) for pharyngeal cancer, and 0.53 (0.22, 1.3) for esophageal cancer. No association was consistently monotonic across exposure categories, and restriction to subjects who never smoked cigarettes yielded similar findings. Conclusions: Our results may have been affected by selection bias or error in measuring lifetime exposure and confounder histories; but they suggest that the association of these cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits. (Cancer Epidemiol Biomarkers Prev 2006;15(10):1829–34)

A randomized trial of medical care with and without physical therapy and chiropractic care with and without physical modalities for patients with low back pain: 6-Month follow-up outcomes from the UCLA low back pain study

Study Design. A randomized clinical trial. Objectives. To compare the effectiveness of medical and chiropractic care for low back pain patients in managed care; to assess the effectiveness of physical therapy among medical patients; and to assess the effectiveness of physical modalities among chiropractic patients. Summary of Background Data. Despite the burden that low back pain places on patients, providers, and society, the relative effectiveness of common treatment strategies offered in managed care is unknown. Methods. Low back pain patients presenting to a large managed care facility from October 30, 1995, through November 9, 1998, were randomly assigned in a balanced design to medical care with and without physical therapy and to chiropractic care with and without physical modalities. The primary outcome variables are average and most severe low back pain intensity in the past week, assessed with 0 to 10 numerical rating scales, and low back-related disability, assessed with the 24-item Roland-Morris Disability Questionnaire. Results. Of 1,469 eligible patients, 681 were enrolled; 95.7% were followed through 6 months. The mean changes in low back pain intensity and disability of participants in the medical and chiropractic care-only groups were similar at each follow-up assessment (adjusted mean differences at 6 months for most severe pain, 0.27, 95% confidence interval, -0.32–0.86; average pain, 0.22, -0.25–0.69; and disability, 0.75, -0.29–1.79). Physical therapy yielded somewhat better 6-month disability outcomes than did medical care alone (1.26, 0.20–2.32). Conclusions. After 6 months of follow-up, chiropractic care and medical care for low back pain were comparable in their effectiveness. Physical therapy may be marginally more effective than medical care alone for reducing disability in some patients, but the possible benefit is small.

Cessation of alcohol drinking, tobacco smoking and the reversal of head and neck cancer risk

BACKGROUND Quitting tobacco or alcohol use has been reported to reduce the head and neck cancer risk in previous studies. However, it is unclear how many years must pass following cessation of these habits before the risk is reduced, and whether the risk ultimately declines to the level of never smokers or never drinkers. METHODS We pooled individual-level data from case-control studies in the International Head and Neck Cancer Epidemiology Consortium. Data were available from 13 studies on drinking cessation (9167 cases and 12 593 controls), and from 17 studies on smoking cessation (12 040 cases and 16 884 controls). We estimated the effect of quitting smoking and drinking on the risk of head and neck cancer and its subsites, by calculating odds ratios (ORs) using logistic regression models. RESULTS Quitting tobacco smoking for 1-4 years resulted in a head and neck cancer risk reduction [OR 0.70, confidence interval (CI) 0.61-0.81 compared with current smoking], with the risk reduction due to smoking cessation after > or =20 years (OR 0.23, CI 0.18-0.31), reaching the level of never smokers. For alcohol use, a beneficial effect on the risk of head and neck cancer was only observed after > or =20 years of quitting (OR 0.60, CI 0.40-0.89 compared with current drinking), reaching the level of never drinkers. CONCLUSIONS Our results support that cessation of tobacco smoking and cessation of alcohol drinking protect against the development of head and neck cancer.