This paper investigates trends in disability in the U.S. population, particularly among people under age fifty. Even as the elderly have become less disabled, reported disability has risen for younger Americans, especially those ages 30-49. We suggest some possible explanations for rising disability levels, such as obesity, technological advances in medicine, and changing disability insurance laws. Obesity and its attendant disorders seem particularly associated with these trends, although the data are not definitive. Whatever its sources, rising disability among the young could have adverse consequences for public programs such as disability insurance, Medicare, and Medicaid.

The goal of this study was to estimate the incidence of Parkinson's disease by age, gender, and ethnicity. Newly diagnosed Parkinson's disease cases in 1994-1995 were identified among members of the Kaiser Permanente Medical Care Program of Northern California, a large health maintenance organization. Each case met modified standardized criteria/Hughes diagnostic criteria as applied by a movement disorder specialist. Incidence rates per 100,000 person-years were calculated using the Kaiser Permanente membership information as the denominator and adjusted for age and/or gender using the direct method of standardization. A total of 588 newly diagnosed (incident) cases of Parkinson's disease were identified, which gave an overall annualized age- and gender-adjusted incidence rate of 13.4 per 100,000 (95% confidence interval (CI): 11.4, 15.5). The incidence rapidly increased over the age of 60 years, with only 4% of the cases being under the age of 50 years. The rate for men (19.0 per 100,000, 95% CI: 16.1, 21.8) was 91% higher than that for women (9.9 per 100,000, 95% CI: 7.6, 12.2). The age- and gender-adjusted rate per 100,000 was highest among Hispanics (16.6, 95% CI: 12.0, 21.3), followed by non-Hispanic Whites (13.6, 95% CI: 11.5, 15.7), Asians (11.3, 95% CI: 7.2, 15.3), and Blacks (10.2, 95% CI: 6.4, 14.0). These data suggest that the incidence of Parkinson's disease varies by race/ethnicity.

Purpose: C-reactive protein (CRP), Chlamydia pneumonia, Helicobacter pylori, and cytomegalovirus (CMV) have each been associated with atherosclerosis. We assessed how infection and CRP related to risk for subsequent myocardial infarction (MI).

Methods: Using a nested case-control design, we assessed how these factors independently and jointly affected risk for myocardial infarction (MI). Cases of first MI (N = 121) were identified from among participants in a multiphasic health check-up cohort. Controls without MI (N = 204) were matched to cases by gender, age, race, and date of serum collection. Sera collected at enrollment were tested for antibodies to infection and for CRP.

Results: In multivariate analysis (mean follow-up of 5.1 years), CRP was associated with MI only in subjects older than 51 years (p = 0.004). Although H. pylori infection increased risk for MI, this association was modest (OR = 1.90, 95% CI = 0.97-3.71) and was not evident in non-smokers or when adjusted for education. No association between C. pneumoniae or cytomegalovirus and MI was observed, nor was the association between CRP and MI explained by these infections.

Conclusions: Elevated CRP is a risk factor for subsequent MI in older individuals. The relationship between Hp and MI may be due to confounding or co-linearity with socioeconomic status.

Helicobacter pylori (HP) infection can cause hypochlorhydria, a positive risk factor for Mycobacterium tuberculosis (MTB) infection. This study examined the association between HP and MTB infections among persons attending the Policlinico Peruano Japones Gastrointestinal Clinic in Lima, Peru. From 23 June 2000 to 18 August 2000, consenting 18-55 year olds who attended the clinic for gastric biopsy gave blood for HP serologic testing, underwent tuberculin skin testing (TST) and completed a social and medical history. Of 128 participating patients, 78 (61%) were TST positive for MTB, and 107 (84%) were infected with HP by serology. Of the patients who were HP positive, 67 (63%) developed positive TST reactions compared to 11 (52%) of 21 HP-seronegative subjects (OR 1.29; 95% CI 0.54-3.11; P = 0.6). There was no association after adjusting for covariates of H. pylori infection (OR 0.78; 95% CI 0.23-2.71; P = 0.7). However, study power was limited by high prevalence of the two infections.

PURPOSE: To compare the diagnostic accuracy of computed tomography (CT) and positron emission tomography (PET) with 18-fluorodeoxyglucose (FDG) for mediastinal staging in patients with non-small-cell lung cancer and to determine whether test results are conditionally dependent (the sensitivity and specificity of FDG-PET depend on the presence or absence of enlarged mediastinal lymph nodes on CT).

DATA SOURCES: Computerized search of MEDLINE, EMBASE, BIOSIS, and CancerLit through March 2003 and reference lists of retrieved studies and review articles.

STUDY SELECTION: Studies in any language that examined FDG-PET for mediastinal staging in patients with known or suspected non-small-cell lung cancer, enrolled at least 10 participants (including at least 5 participants with mediastinal metastasis), and provided enough data to permit calculation of sensitivity and specificity for identifying lymph node involvement.

DATA EXTRACTION: One reviewer (of non-English-language studies) or 2 reviewers (of English-language studies) independently evaluated studies for inclusion, rated methodologic quality, and abstracted relevant data.

DATA SYNTHESIS: Thirty-nine studies met inclusion criteria. Methodologic quality varied, but few aspects of study quality affected diagnostic accuracy. The authors constructed summary receiver-operating characteristic curves for CT and FDG-PET. Positron emission tomography with 18-fluorodeoxyglucose was more accurate than CT for identifying lymph node involvement (P 0.001). For CT, median sensitivity and specificity were 61% (interquartile range, 50% to 71%) and 79% (interquartile range, 66% to 89%), respectively. For FDG-PET, median sensitivity and specificity were 85% (interquartile range, 67% to 91%) and 90% (interquartile range, 82% to 96%), respectively. Fourteen studies provided information about the conditional test performance of CT and FDG-PET. Positron emission tomography with 18-fluorodeoxyglucose was more sensitive but less specific when CT showed enlarged lymph nodes (median sensitivity, 100% [interquartile range, 90% to 100%]; median specificity, 78% [interquartile range, 68% to 100%]) than when CT showed no lymph node enlargement (median sensitivity, 82% [interquartile range, 65% to 100%]; median specificity, 93% [interquartile range, 92% to 100%]; P = 0.002).

CONCLUSIONS: Positron emission tomography with 18-fluorodeoxyglucose is more accurate than CT for mediastinal staging. Positron emission tomography with 18-fluorodeoxyglucose is more sensitive but less specific when CT shows enlarged mediastinal lymph nodes.

This abstract was presented by Patrick Romano at the Annual Meeting for the International Society of Quality on November 3, 2003.

We analyze the relationship between the supply of new technologies and health care utilization and spending, focusing on diagnostic imaging, cardiac, cancer, and newborn care technologies. As anticipated by previous research, increases in the supply of technology tend to be related to higher utilization and spending on the service in question. In some cases, notably diagnostic imaging, increases in availability appear associated with incremental utilization rather than substitution for other services. Policy efforts to assess and manage the availability of new technologies could benefit society where the additional spending produced by new services is not associated with strong quality improvements.

Using data from the National Health and Nutrition Examination Survey, we examine the relationship between nutritional status, poverty, and food insecurity for household members of various ages. Our most striking result is that, while poverty is predictive of poor nutrition among preschool children, food insecurity does not provide any additional predictive power for this age group. Among school age children, neither poverty nor food insecurity is associated with nutritional outcomes, while among adults and the elderly, both food insecurity and poverty are predictive. These results suggest that researchers should be cautious about assuming connections between food insecurity and nutritional outcomes, particularly among children.

BACKGROUND: Clinicians need self-directed learning skills to maintain competency. The objective of this study was to develop and implement a curriculum to teach physicians self-directed learning skills during inpatient ward rotations. METHODS: Residents and attendings from an internal medicine residency were assigned to intervention or control groups; intervention physicians completed self-directed learning curricular exercises. RESULTS: Among the 43 intervention physicians, 21 (49%) completed pre- and post-curriculum tests; and 10 (23%) completed the one-year test. Immediately after exposure to the curriculum, the proportion of physicians defining short- and long-term learning goals increased [short-term: 1/21 (5%) to 11/21 (52%), p=0.001; long-term: 2/21 (10%) to 15/21 (71%), p=0.001]. There were no significant changes post-curriculum in the quantity or quality of clinical question asking. The physicians' mean self-efficacy (on a 100-point scale)improved for their abilities to develop a plan to keep up with the medical literature (59 vs. 72, p=0.04). The effects of the curriculum on self-reported learning behaviors was maintained from the immediate post-curriculum test to the one-year post-curriculum test: [short-term learning goals: 1/21 (5%) pre-, 11/21 (52%) immediately post-, and 5/10 (50%) one-year after the curriculum (p=0.0075 for the pre- vs one-year comparison); long-term learning goals: 2/21 (10%) pre-, 15/21 (71%) immediately post-, and 7/10 (70%) one-year (p=0.0013 for the pre- vs. one-year comparison). At one year, half of the participants reported changed learning behaviors. CONCLUSION: A four-week curriculum may improve self-directed learning skills.