Trends in HIV Testing Among U.S. Older Adults Prior to and Since Release of CDC's Routine HIV Testing Recommendations: National Findings from the BRFSS

Objective

This study examined temporal trends in HIV testing among U.S. older adults (50–64 years of age) before and after the release of CDC''s routine HIV testing recommendations in 2006.

Methods

The sample (n=872,797; 51.4% female) comprised 2003–2010 Behavioral Risk Factor Surveillance System respondents in the oldest categories to which the recommendations apply: 50–54 years (34.5%, n=301,519), 55–59 years (34.1%, n=297,865), and 60–64 years (31.3%, n=273,413). We calculated (1) four-year pooled prevalences of past-year HIV testing before and after 2006, when the recommendations were released; and (2) annual prevalences of HIV testing overall and by age category from 2003–2010. Using weighted, multivariable logistic regression analyses, we examined binary (pre- vs. post-recommendations) and annual changes in testing, controlling for covariates. We stratified the data by recent doctor visits, examined racial/ethnic differences, and tested for linear and quadratic temporal trends.

Results

Overall and within age categories, the pooled prevalence of past-year HIV testing decreased following release of the recommendations (p<0.001). The annual prevalence decreased monotonically from 2003 (5.5%) to 2006 (3.6%) (b=–0.16, p<0.001) and then increased immediately after release of the recommendations, but decreased to 3.7% after 2009 (b=0.01, p<0.001). By race/ethnicity, testing increased over time among non-Hispanic black people only. Annual prevalence also increased among respondents with recent doctor visits.

Conclusion

CDC''s HIV testing recommendations were associated with a reversal in the downward trend in past-year HIV testing among older adults; however, the gains were neither universal nor sustained over time.In 2006, the Centers for Disease Control and Prevention (CDC) began recommending routine opt-out human immunodeficiency virus (HIV) testing of all adults <65 years of age seeking health care in any setting where HIV prevalence is ≥0.1%.¹ Routine testing is an efficient, cost-effective strategy for early detection of HIV infection.² It involves screening every patient (except those who decline testing) regardless of any reported risk behaviors; therefore, it can facilitate detection of undiagnosed HIV infection among people unlikely to seek an HIV test, including those presumed to have little or no HIV risk.³Routine testing may be particularly important for older adults (i.e., those aged ≥50 years), among whom 11% of U.S. HIV infections occur. Of concern, HIV-infected older adults are disproportionately diagnosed late in the course of HIV disease.^4,5 Late diagnosis is associated with rapid progression to acquired immunodeficiency syndrome (AIDS), and it exacerbates the management of both HIV disease and the non-HIV conditions that are prevalent among older adults (e.g., hypertension).^6–9 Rates of HIV testing generally decrease with age;^10–13 however, it is unclear if the release and implementation of the recommendations have helped to improve HIV testing levels in this age group.^14,15To understand the recommendations'' potential influence on HIV testing among older adults, we examined trends in HIV testing from January 1, 2003, to December 31, 2010, among Behavioral Risk Factor Surveillance System (BRFSS) respondents in the three categories of older adulthood (50–54, 55–59, and 60–64 years of age) to which the routine HIV testing recommendations apply. The study period began four years prior to CDC''s publication of the recommendations and concluded four years thereafter, enabling us to compare HIV testing levels before and after their release. Full implementation should produce a sustained increase in testing that begins in 2007 and is most apparent among people with a recent doctor visit. This study sought to determine if:

1. The annual prevalence of past-year HIV testing increased among older adults since release of the routine HIV testing recommendations,
2. Racial/ethnic differences in past-year HIV testing exist over time among older adults,
3. The odds of testing increased more for those with vs. without a recent doctor visit since release of the recommendations, and
4. The characteristics of older testers changed over time.

     

Predictors of New Airway Obstruction – An 11 Year’s Population-Based Follow-Up Study

In the present study we aimed to investigate the incidence and predictors of spirometry based airway obstruction in a representative population-based sample. Altogether 3,863 subjects, 1,651 males and 2,212 females aged ≥30 years had normal spirometry in year 2000. Fifty-three percent of them were never and 23% current smokers. A re-spirometry was performed 11 years later. Several characteristics, such as level of education, use of alcohol, physical activity, diet using Alternate healthy eating (AHEI) index, body mass index, circumwaist, sensitive C reactive protein (CRP) and cotinine of the laboratory values and co-morbidities including asthma, allergic rhinitis, sleep apnoea and chronic bronchitis, as potential risk factors for airway obstruction were evaluated. Using forced expiratory volume in one second/ forced vital capacity below the lower limit of normal, we observed 124 new cases of airway obstruction showing a cumulative 11-year incidence of 3.2% and corresponding to an incidence rate of 5.6/1,000 per year (PY). The incidence rate was higher in men than in women (6.3/1,000 PY vs. 5.0/1,000 PY, respectively). The strongest risk factors were current smoking (Odds ratio [OR] 2.5) and previously diagnosed asthma (OR 2.1). Sensitive CRP associated with the increased risk and high AHEI index with the decreased risk of airway obstruction. Using the similar study approach our findings on the incidence of airway obstruction are in line with the previously published figures in Europe. We were able to confirm the recent findings on the protective effect of healthy diet.     

Comparison of spherical and realistically shaped boundary element head models for transcranial magnetic stimulation navigation

Objective

MRI-guided real-time transcranial magnetic stimulation (TMS) navigators that apply electromagnetic modeling have improved the utility of TMS. However, their accuracy and speed depends on the assumed volume conductor geometry. Spherical models found in present navigators are computationally fast but may be inaccurate in some areas. Realistically shaped boundary-element models (BEMs) could increase accuracy at a moderate computational cost, but it is unknown which model features have the largest influence on accuracy. Thus, we compared different types of spherical models and BEMs.

Methods

Globally and locally fitted spherical models and different BEMs with either one or three compartments and with different skull-to-brain conductivity ratios (1/1–1/80) were compared against a reference BEM.

Results

The one-compartment BEM at inner skull surface was almost as accurate as the reference BEM. Skull/brain conductivity ratio in the range 1/10–1/80 had only a minor influence. BEMs were superior to spherical models especially in frontal and temporal areas (up to 20 mm localization and 40% intensity improvement); in motor cortex all models provided similar results.

Conclusions

One-compartment BEMs offer a good balance between accuracy and computational cost.

Significance

Realistically shaped BEMs may increase TMS navigation accuracy in several brain areas, such as in prefrontal regions often targeted in clinical applications.