Cessation from Smoking Improves Innate Host Defense and Clearance of Experimentally Inoculated Nasal Staphylococcus aureus.

Staphylococcus aureus nasal carriage is transient in most humans and usually benign, but dissemination of S. aureus to extranasal sites causes the majority of clinical infections, and S. aureus is a major cause of serious infections in the United States. A better understanding of innate nasal decolonization mechanisms is urgently needed, as are relevant models for studying S. aureus clearance. Here, we screened a population of healthy smokers for nasal S. aureus carriage and compared the participants' abilities to clear experimentally applied nasal S. aureus before and after completion of a smoking cessation program. We determined that cigarette smoking increases the mean nasal S. aureus load (2.6 × 104 CFU/swab) compared to the load observed in healthy nonsmokers (1.7 × 103 CFU/swab) and might increase the rate of S. aureus nasal carriage in otherwise-healthy adults: 22 of 99 smokers carried S. aureus at the screening visit, while only 4 of 30 nonsmokers screened positive during the same time period. Only 6 of 19 experimental inoculation studies in active smokers resulted in S. aureus clearance within the month of follow-up, while in the cessation group, 6 of 9 subjects cleared nasal S. aureus and carriage duration averaged 21 ± 4 days. Smoking cessation associated with enhanced expression of S. aureus-associated interleukin-1ß (IL-1ß) and granulocyte colony-stimulating factor (G-CSF) in nasal fluids. Participants who failed to clear S. aureus exhibited a higher nasal S. aureus load and elevated nasal interleukin-1 receptor antagonist (IL-1RA) expression at the preexperiment study visits. We conclude that smokers exhibit higher S. aureus loads than nonsmokers and that innate immune pathways, including G-CSF expression and signaling through the IL-1 axis, are important mediators of nasal S. aureus clearance.

Genetic assessment of Staphylococcus aureus in an underreported locality: Ambulatory care clinic.

BACKGROUND: Staphylococcus aureus has strong association with anthropogenic environments. This association has not been well supported by use of genetic tools. The aim of this study was to phylogenetically relate numerous isolates from three environments - NCBI samples from hospitals, a community, and a previously unexplored healthcare environment: an ambulatory care clinic (ACC). METHODS: This study incorporated hospital samples from NCBI, a community database from the University of Central Florida (UCF), and newly added samples taken from employees of an ambulatory care clinic located at UCF. Samples were collected from nasal swabs of employees, and positive samples were cultured, extracted, and sequenced at seven MLST loci and one virulence locus (spa). MLST sequences were used in eBURST and TCS population structure analyses and all sequences were incorporated into a phylogenetic reconstruction of relationships. RESULTS: A total of 185 samples were incorporated in this study (15 NCBI sequences from hospital infections, 29 from the ACC, and 141 from the community). In both phylogenetic and population genetics analyses, samples proved to be panmixic, with samples not segregating monophyletically based on sample origin. CONCLUSION: Samples isolated from ambulatory care clinics are not significantly differentiated from either community or hospital samples at the representative loci chosen. These results strengthen previous conclusions that S. aureus may exhibit high genetic similarity across anthropogenic environments.

The Relationship of Undergraduate Major and Housing with Depression in Undergraduate Students.

INTRODUCTION: Past literature has shown that college undergraduates are particularly vulnerable to depression. The objective of this study is to find if certain majors and housing arrangements are associated with major depression as assessed by the Patient Health Questionnaire (PHQ-9), after adjustment for age, gender, and family history of depression. METHODS: Participants were undergraduates at a large public university that used the university health center from April 1 - November 4, 2013. Participants completed a survey which included the PHQ-2, a validated screening test for depression. Those who scored positive were asked to take the longer PHQ-9 survey to assess for major depression. Logistic regression was used to test the significance of associations between several prescribed variables (namely, college major, housing arrangement, age, gender, and family history of depression) and outcome (major depression as assessed by the PHQ-9). RESULTS: Of 541 students, 71 (13.1%) scored positive on the PHQ-9 for depression. Family history was significantly associated (OR 4.20, 95% CI, 2.42, 7.29) with major depressive disorder, as was a major in the College of Arts and Humanities (OR 3.84, 95% CI, 1.18, 12.46) compared to the baseline of an undecided/interdisciplinary major. CONCLUSIONS: A major in the College of Arts and Humanities was significantly associated with major depression. This may be significant for future efforts to target mental health interventions on college campuses.

Screening for high-risk drinking in a college student health center: characterizing students based on quantity, frequency, and harms.

OBJECTIVE: This study examined characteristics of students who presented to a college health center and screened positive for the 5/4 definition of high-risk drinking (five or more drinks in a row for men, or four or more drinks in a row for women, on at least one occasion in the past 2 weeks) and analyzed the students' data according to their reporting of alcohol-related harms. METHOD: Secondary analysis of data obtained for an intervention study to reduce high-risk drinking in college students was used. Data on alcohol use and alcohol-related harms were obtained from Web-based Healthy Lifestyle Questionnaires and 30-day alcohol recall diaries (Timeline Followback calendar). Students (N = 363; 52% female) were classified as nonheavy, heavy, and heavy and frequent drinkers, based on their self-reported alcohol use. Alcohol-related harms were measured using the Rutgers Alcohol Problem Index and eight additional items derived from the Drinker Inventory of Consequences-2L. RESULTS: Students in the nonheavy, heavy, and heavy and frequent groups had mean Rutgers Alcohol Problem Index scores of 10, 14, and 23, respectively. The heavy-and-frequent drinking group comprised 20% of the sample but experienced 31% of the total harms. CONCLUSIONS: The 5/4 screening question accurately identified college students presenting to a college health center who were already experiencing significant alcohol-related harms. The addition of a frequency question (drinking 3 or more days per week) to the 5/4 screening question provided a simple method for identifying those students at highest risk and in greatest need of intervention.

Alcohol screening and brief intervention in a college student health center: a randomized controlled trial.

OBJECTIVE: This study tested the effectiveness of brief primary care provider interventions delivered in a college student health center to a sample of college students who screened positive for high-risk drinking. METHOD: Between November 2005 and August 2006, 8,753 students who presented as new patients to the health service at a large public university were screened for high-risk drinking, and 2,484 students (28%) screened positive on the 5/4 gender-specific high-risk drinking question (i.e., five or more drinks per occasion for men and four or more for women). Students who screened positive for high-risk drinking and consented to participate (N= 363; 52% female) were randomly assigned either to a control group (n = 182) or to an experimental group (n = 181). Participants in the experimental group received two brief intervention sessions that were founded in motivational interviewing techniques and delivered by four specially trained providers within the student health center. Data on alcohol use and related harms were obtained from a Web-based Healthy Lifestyle Questionnaire, 30-day Timeline Followback alcohol-use diaries, the Rutgers Alcohol Problem Index (RAPI), and eight items from the Drinker Inventory of Consequences-2L. RESULTS: Repeated measures analysis showed that, compared with the control group (C), the intervention group (I) had significant reductions in typical estimated blood alcohol concentration (BAC) (C = .071 vs I = .057 at 3 months; C = .073 vs I = .057 at 6 months), peak BAC (C = . 142 vs I = .112 at 3 months; C = .145 vs I = .108 at 6 months), peak number of drinks per sitting (C = 8.03 vs I = 6.87 at 3 months; C = 7.98 vs I = 6.52 at 6 months), average number of drinks per week (C = 9.47 vs I = 7.33 at 3 months; C = 8.90 vs I = 6.16 at 6 months), number of drunk episodes in a typical week (C = 1.24 vs I = 0.85 at 3 months; C = 1.10 vs I = 0.71 at 6 months), number of times taken foolish risks (C = 2.24 vs I = 1.12 at 3 months), and RAPI sum scores (C = 6.55 vs I = 4.96 at 6 months; C = 6.17 vs I = 4.58 at 9 months). CONCLUSIONS: Brief interventions delivered by primary care providers in a student health center to high-risk-drinking students may result in significantly decreased alcohol consumption, high-risk drinking, and alcohol-related harms.