Inconclusive findings about infection risks, importantly the use of immunosuppressive medications in patients who have undergone large-joint total joint arthroplasty, challenge efforts to provide evidence-based perioperative total joint arthroplasty recommendations to improve surgical outcomes. Thus, the aim of this study was to describe risk factors for developing a post-operative infection in patients undergoing TJA of a large joint (total hip arthroplasty, total knee arthroplasty, or total shoulder arthroplasty) by identifying clinical and demographic factors, including the use of high-risk medications (i.e., prednisone and immunosuppressive medications) and diagnoses [i.e., rheumatoid arthritis (RA), osteoarthritis (OA), gout, obesity, and diabetes mellitus] that are linked to infection status, controlling for length of follow-up. A retrospective, case-control study (N = 2212) using de-identified patient health claims information from a commercially insured, U.S. dataset representing 15 million patients annually (from January 1, 2007 to December 31, 2009) was conducted. Descriptive statistics, t-test, chi-square test, Fisher's exact test, and multivariate logistic regression were used. Male gender (OR = 1.42, p < 0.001), diagnosis of RA (OR = 1.47, p = 0.031), diabetes mellitus (OR = 1.38, p = 0.001), obesity (OR = 1.66, p < 0.001) or gout (OR = 1.95, p = 0.001), and a prescription for prednisone (OR = 1.59, p < 0.001) predicted a post-operative infection following total joint arthroplasty. Persons with post-operative joint infections were significantly more likely to be prescribed allopurinol (p = 0.002) and colchicine (p = 0.006); no significant difference was found for the use of specific disease-modifying anti-rheumatic drugs and TNF-α inhibitors. High-risk, post-operative joint infection groups were identified allowing for precautionary clinical measures to be taken.

Objective: To examine the association of secondhand smoke (SHS) exposure with susceptibility to smoking, perceived addiction, and psychobehavioral effects of exposure among never- and ever-smoking college students. Participants: Participants were 665 college students at a large, southeastern university in the United States. Methods: This study is a secondary analysis of online cross-sectional survey data from randomly selected students in April 2013. Results: Thirty-eight percent of the sample had moderate to high SHS exposure. Among never-smokers, SHS exposure was associated with increased susceptibility to initiating smoking. Among ever-smokers, SHS exposure was not associated with their perceived addiction to tobacco. In the total sample, SHS exposure was associated with greater psychobehavioral symptoms of exposure. Conclusions: SHS exposure may the increase risk of smoking, especially among never-smoking college students. This study strengthens the need for prevention strategies that limit SHS exposure in college environments.

We combined 71,930 short‐term (median duration 4 days) home radon test results with 1:24,000‐scale bedrock geologic map coverage of Kentucky to produce a statewide geologically based indoor‐radon potential map. The test results were positively skewed with a mean of 266 Bq/m³, median of 122 Bq/m³, and 75th percentile of 289 Bq/m³. We identified 106 formations with ≥10 test results. Analysis of results from 20 predominantly monolithologic formations showed indoor‐radon concentrations to be positively skewed on a formation‐by‐formation basis, with a proportional relationship between sample means and standard deviations. Limestone (median 170 Bq/m³) and dolostone (median 130 Bq/m³) tended to have higher indoor‐radon concentrations than siltstones and sandstones (median 67 Bq/m³) or unlithified surficial deposits (median 63 Bq/m³). Individual shales had median values ranging from 67 to 189 Bq/m³; the median value for all shale values was 85 Bq/m³. Percentages of values falling above the U.S. Environmental Protection Agency (EPA) action level of 148 Bq/m³ were sandstone and siltstone: 24%, unlithified clastic: 21%, dolostone: 46%, limestone: 55%, and shale: 34%. Mississippian limestones, Ordovician limestones, and Devonian black shales had the highest indoor‐radon potential values in Kentucky. Indoor‐radon test mean values for the selected formations were also weakly, but statistically significantly, correlated with mean aeroradiometric uranium concentrations. To produce a map useful to nonspecialists, we classified each of the 106 formations into five radon‐geologic classes on the basis of their 75th percentile radon concentrations. The statewide map is freely available through an interactive internet map service.