The association between body mass index and arthritis among US adults: CDC's surveillance case definition.

INTRODUCTION: The Centers for Disease Control and Prevention modified the surveillance case definition of arthritis to a more stringent form in 2002. To date, the association between arthritis and obesity (an established risk factor for arthritis) has not been examined with the new definition. We describe the association between body mass index (BMI) (kg/m(2)) and arthritis using the new arthritis case definition to provide a more accurate assessment of the relationship between weight and arthritis among US adults. METHODS: We used data from the 2005 Behavioral Risk Factor Surveillance System (N = 356,112) and univariate and multivariate analyses to assess the relationship between BMI and arthritis among US adults. RESULTS: Overall, 26% of US adults had self-reported arthritis. Obese respondents (BMI >or=30.0 kg/m(2)) were 1.9 times more likely to report arthritis compared with normal-weight respondents (BMI <25.0 kg/m(2)), and distinguishing between obese levels revealed an even greater association between BMI and arthritis (class III obesity [BMI >or=40.0], odds ratio [OR] = 3.3, 95% confidence interval [CI] = 3.1-3.6; class II obesity [BMI 35.0-39.9 kg/m2], OR = 2.5, 95% CI = 2.3-2.7; class I obesity [BMI 30.0-34.9], OR = 1.9, 95% CI = 1.8-2.0). CONCLUSION: BMI is an independent risk factor for self-reported arthritis. Maintaining a healthy weight may delay the onset of arthritis. More research is needed to determine the effect of weight loss on the progression of arthritis in overweight individuals.

Correlation between high risk obesity groups and low socioeconomic status in school children.

OBJECTIVE: Obesity is a major health problem among children and adolescents which is potentially affected by socioeconomic status (SES). The high risk group (HRG) comprises those youths with a body mass index (BMI) between the 85th and 95th percentile (at risk for overweight) and > or = 95th percentile (overweight). We sought a potential link between the HRG and SES. METHODS: Public schools in Chesterfield County, Virginia measured BMI among students in kindergarten and third, seventh, and tenth grades. We assessed SES based on eligibility for the National School Lunch Program and the percentage of the school-age population living in poverty based on per capita income from the 2000 Census. RESULTS: From 28 to 38% of children and adolescents were in the high risk group. Low SES had robust and highly significant correlations with HRG status with r-values ranging from 0.565 to 0.842, P < 0.0001. CONCLUSIONS: Low SES appears to be an important factor in childhood and adolescent obesity.

Toxicology findings in child and adolescent suicides in virginia: 1987-2003.

OBJECTIVE: In a follow-up report of child and adolescent suicides in Virginia, we describe postmortem toxicology findings in a subset of these youths. METHOD: We analyzed "unnatural" deaths from Virginia's Office of the Chief Medical Examiner for 1987 to 2003. There were 2818 unnatural deaths in children and adolescents. We grouped unnatural deaths as accidents, homicides, and suicides. Toxicology records were available for 753 cases, of which 732 were black or white youths. RESULTS: There were no age differences among suicide victims and accident or homicide victims. Whites were more likely than blacks to die by accident and suicide. White females were more likely than black females to commit suicide. Black males were more likely than white males to suffer homicide. For all unexpected deaths, antidepressants were more commonly found among whites than blacks. Suicide by poisoning occurred more commonly among whites. Recreational drugs were more commonly found among blacks than whites. Suicide by gun occurred more commonly among blacks. Antidepressants were found in 39 black and white suicide victims. Anti-depressants (all tricyclic antidepressants) were causally related in 17 cases of suicide by poisoning. No other antidepressants were found in lethal levels in suicide by poisoning. Selective serotonin reuptake inhibitors (SSRIs)/venlafaxine appeared more commonly in the suicides (p < .0001) than in accidents or homicides. For suicides, SSRIs appeared no more commonly in poisoning than in gun or hanging deaths (p = .695). CONCLUSIONS: Antidepressants appeared more commonly among youths committing suicide than those dying by accident or homicide. SSRIs did not appear more commonly among youths committing suicide by poisoning than those committing suicide by gun or hanging. Because our data are descriptive, they are subject to over-interpretation. Cause-effect inferences should not be drawn.

Straight talk. New approaches in healthcare.

Not-for-profit health systems are under the public microscope. Sen. Charles Grassley, (D-Iowa) chairman of the Senate Finance Committee, has been critical of the charity care and billing practices of not-for-profit health systems, and vows to introduce legislation to correct abuses throughout the tax-exempt sector. The House has studied the issue as well. Not-for-profit health systems also have been accused in hundreds of lawsuits of overcharging uninsured patients and aggressively pursuing debt collection. In this installment of Straight Talk, we explore the issues surrounding tax-exempt status and how health systems should publicize their charitable work. Modern Healthcare and PricewaterhouseCoopers present Straight Talk. The session on charity care and tax-exempt status was held on October 4, 2005 at Modern Healthcare's Chicago headquarters. Fawn Lopez, publisher of Modern Healthcare, was the moderator.

Predicting premature mortality from new power plant development in Virginia.

The authors estimated the number of premature deaths from particulate matter less than 2.5 microm (PM2.5) that would result from making 29 proposed fossil fuel power plants in Virginia operational. We used a U.S. Environmental Protection Agency air quality model (Climatological Regional Dispersion model) to calculate changes in ambient concentrations of PM2.5 and Cox proportional hazard modeling to calculate the resulting premature mortality. The model predicted that if all 29 plants were operational, PM2.5 concentrations would rise in 271 counties across 19 states 5 and increased average annual PM2.5 concentrations would result in a rate of 17 deaths per 37,900,026 people aged 30 yr and older (0.45 deaths per million, 95% confidence interval = 0.31, 0.59) per year by the end of 2004, increasing thereafter. Over a 6 yr period, 104 cumulative excess deaths would occur due to operations of these proposed plants. The authors recommend that precautionary principles be considered when policy decisions related to energy production from fossil fuels are made.

Saltating motion of a bead in a rapid water stream.

This paper experimentally and numerically investigates the two-dimensional saltating motion of a single large particle in a shallow water stream down a steep rough bed. The experiment is prototypical of sediment transport on sloping beds. Similar to the earlier experimental results on fine particles entrained by a turbulent stream, we found that most features of the particle motion were controlled by a dimensionless shear stress (also called the Shields number) N(Sh) defined as the ratio of the bottom shear stress exerted by the water flow to the buoyant weight of the particle (scaled by its cross-sectional area to obtain a stress). We did not observe a clear transition from rest to motion, but on the contrary there was a fairly wide range of N(Sh) (typically 0.001-0.005 for gentle slopes) for which the particle could be set in motion or come to rest. When the particle was set in motion, it systematically began to roll. The rolling regime was marginal in that it occurred for a narrow range of N(Sh) (typically 0.005-0.01 for gentle slopes). For sufficiently high Shields numbers (N(Sh)>0.3), the particle was in saltation. The mean particle velocity was found to vary linearly with the square root of the bottom shear stress and here, surprisingly enough, was a decreasing function of the channel slope. We also performed numerical simulations based on Lagrangian equations of motion. A qualitative agreement was found between the experimental data and numerical simulations but, from a quantitative point of view, the relative deviation was sometimes substantial (as high as 50%). An explanation for the partial agreement is the significant modification in the water flow near the particle.