General Population Subgroups Research Articles

The link between elevated long-term resting heart rate and SBP variability for all-cause mortality.

Resting heart rate (RHR) and SBP are important risk markers for all-cause mortality. However, the link between increased RHR and SBP for all causes of death remained unclear. We investigated the link between an increased visit-to-visit variation of RHR and SBP for risk of all-cause mortality in the general population. We examined long-term visit-to-visit variation of RHR and blood pressure among 46 751 residents of Tangshan city, China (mean age: 52.58 ± 11.64 years; 78% men). Cox proportional hazard model was used to estimate the hazard ratios and 95% confidence interval (CI) adjusting for clinical characteristics assessed at the last examination (2010-2011). A total of 1667 deaths were recorded over 4.97 ± 0.69 years follow-up. A rise in 1 SD of heart rate (4 bpm) was associated with an increased risk of death among the participants in third and fourth quartile of SBP-SD in the subgroups of general population [hazard ratio (95% CI) = 1.10 (1.03-1.67) and 1.16 (1.03-1.30), respectively], men [hazard ratio (95% CI) = 1.10 (1.02-1.17) and 1.16 (1.03-1.30), respectively], and participants under 65 years of age [hazard ratio (95% CI) = 1.16 (1.02-1.33) and 1.20 (1.03-1.39), respectively]. Similarly, 1-SD increase of SBP (7 mmHg) was associated with an increased risk of death among the participants in the highest quartiles of RHR-SD in the subgroups of the general population, men, and under 65 years of age. An elevated long-term SBP variability combined with an increased RHR variability or vice versa may amplify the risk of all-cause mortality in general population, as well as in men and middle-age group.

Implementing an Internet-Delivered Skin Cancer Genetic Testing Intervention to Improve Sun Protection Behavior in a Diverse Population: Protocol for a Randomized Controlled Trial.

BackgroundLimited translational genomic research currently exists to guide the availability, comprehension, and appropriate use of personalized genomics in diverse general population subgroups. Melanoma skin cancers are preventable, curable, common in the general population, and disproportionately increasing in Hispanics.ObjectiveVariants in the melanocortin-1 receptor (MC1R) gene are present in approximately 50% of the population, are major factors in determining sun sensitivity, and confer a 2-to-3-fold increase in melanoma risk in the general population, even in populations with darker skin. Therefore, feedback regarding MC1R risk status may raise risk awareness and protective behavior in the general population.MethodsWe are conducting a randomized controlled trial examining Internet presentation of the risks and benefits of personalized genomic testing for MC1R gene variants that are associated with increased melanoma risk. We will enroll a total of 885 participants (462 participants are currently enrolled), who will be randomized 6:1 to personalized genomic testing for melanoma risk versus waiting list control. Control participants will be offered testing after outcome assessments. Participants will be balanced across self-reported Hispanic versus non-Hispanic ethnicity (n=750 in personalized genomic testing for melanoma risk arm; n=135 in control arm), and will be recruited from a general population cohort in Albuquerque, New Mexico, which is subject to year-round sun exposure. Baseline surveys will be completed in-person with study staff and follow-up measures will be completed via telephone.ResultsAim 1 of the trial will examine the personal utility of personalized genomic testing for melanoma risk in terms of short-term (3-month) sun protection and skin screening behaviors, family and physician communication, and melanoma threat and control beliefs (ie, putative mediators of behavior change). We will also examine potential unintended consequences of testing among those who receive average-risk personalized genomic testing for melanoma risk findings, and examine predictors of sun protection at 3 months as the outcome. These findings will be used to develop messages for groups that receive average-risk feedback. Aim 2 will compare rates of test consideration in Hispanics versus non-Hispanics, including consideration of testing pros and cons and registration of a decision to either accept or decline testing. Aim 3 will examine personalized genomic testing for melanoma risk feedback comprehension, recall, satisfaction, and cancer-related distress in those who undergo testing, and whether these outcomes differ by ethnicity (Hispanic vs non-Hispanic), or sociocultural or demographic factors. Final outcome data collection is anticipated to be complete by October 2017, at which point data analysis will commence.ConclusionsThis study has important implications for personalized genomics in the context of melanoma risk, and may be broadly applicable as a model for delivery of personalized genomic feedback for other health conditions.

Pressure to change drinking behavior: An exploratory analysis of US general population subgroups.

General population studies have shown that pressure from others to change drinking can come from different sources. Receipt of informal pressure (IP) and formal pressure (FP) is known to vary by quantity and consequences of drinking, but less is known about how pressure varies among subgroups of the population. This exploratory study utilizes data from the National Alcohol Surveys from 1995-2010 (N=26,311) and examines associations between receipt of pressure and subgroups of drinkers. Increased relative risk of receiving IP and FP were observed for individuals reporting an arrest for driving after drinking and illicit drug use while poverty and lack of private health insurance increased risk of receipt of formal pressures. Regular marijuana use increased IP. The subgroups that were studied received increased pressures to change drinking behavior, though disentangling the societal role of pressure and how it may assist with interventions, help seeking, and natural recovery is needed.

O13.2 Can the UNAIDS Modes of Transmission Model Be Improved? A Comparison of the Original and Revised Model Projections Using Data from Nigeria

Mathematical modelling has increased our understanding of the HIV epidemic and played a key role in decision making. The UNAIDS Modes of Transmission (MoT) model has been used by 29 countries to analyse their HIV epidemics, with the results helping to guide and focus interventions. However, the simplistic compartmentalisation of the population within the model has raised concerns over its reliability.We compared the MoT model projections for Cross River, Nigeria, with a revised MoT model that incorporates additional heterogeneity (including subgroups for sero-discordant partnerships and individuals engaging in transactional sex) and updated parameters. We categorised population subgroups into ‘high-risk’, representing core groups, their bridging partners and sero-discordant partnerships; ‘medium-risk’, who are regular partners of ‘high-risk’ individuals; and ‘general population’, who are not linked to ‘high-risk’ or ‘medium-risk’ groups. Sensitivity analyses were undertaken and model projections assessed which population categories generated the highest incidence of HIV.The original MoT model projections suggest 73% of HIV infections occur in general population subgroups and 21% amongst ‘high-risk’ groups. Following revisions to the MoT, model projections estimate 76–94% (95%CrI) of new HIV infections are expected to occur in high-risk groups, who make up just 23% of the population, compared to 6–24% amongst general population subgroups. Changes in the distribution of infections result from the introduction of sero-discordant partnerships and ‘transactional sex’ groups (a relatively large subset of the population, often ignored in modelling analysis) in the model, which are classified as ‘high-risk’.The UNAIDS MoT remains an accessible and potentially useful model that can help inform intervention priorities. However, our findings strongly suggest that the current model may produce misleading findings, especially in more concentrated HIV epidemic settings. Results from this study indicate the need for UNAIDS to conduct a formal review of the MoT, and for further revisions to be made.

Environmental and lifestyle factors affect benzene uptake biomonitoring of residents near a petrochemical plant

Background We monitored urinary benzene excretion to examine factors affecting benzene uptake in a sample of the general population living near a petrochemical plant. Methods Our study population included 143 subjects: 33 petrochemical plant workers (W) with low level occupational benzene exposure; 30 residents in a small town 2 km from the plant (2kmR); 26 residents in a second small town located 2 to 4 km from the plant (4kmR); and 54 urban residents 25 km from the plant (25kmR). Exposure to benzene was evaluated by personal air sampling during one work-shift for the W group, and from 8.00 to 20:00 for general population subgroups, and by urinary benzene (BEN-U). Results Median airborne benzene exposure was 25, 9, 7 and 6 μg/m 3 benzene among the W, 2kmR, 4kmR, and 25kmR subgroups, respectively; the highest level was found among the workers, while there was no significant difference among the other groups. Median BEN-U was 2 to 14-fold higher in smokers compared to non-smokers; among non-smokers BEN-U was the highest in W (median 236 ng/L), and lower in the 2kmR (48 ng/L) and 4kmR (63 ng/L) subgroups than in the 25kmR (120 ng/L) subgroup. A multiple linear regression analysis, explaining up to 73% of BEN-U variability, confirmed that active smoking and airborne benzene most strongly affected BEN-U. Among the non-smoking, non-occupationally exposed study subjects, a positive association was found between BEN-U and the distance of residence from the plant. This association was explained by increased exposure to urban traffic emissions in the study group residing at a greater distance from the plant. Environmental tobacco smoke had a marginally positive role. Conclusion Among factors affecting benzene uptake in non-occupationally exposed individuals, urban residence contributes to benzene exposure more than residing in close proximity to a petrochemical plant.

Neck pain and anxiety do not always go together

Chronic pain and psychosocial distress are generally thought to be associated in chronic musculoskeletal disorders such as non-specific neck pain. However, it is unclear whether a raised level of anxiety is necessarily a feature of longstanding, intense pain amongst patient and general population sub-groups. In a cohort of 70 self-selected female, non-specific neck pain sufferers, we observed relatively high levels of self-reported pain of 4.46 (measured on the 11 point numerical pain rating scale (NRS-101)) and a longstanding duration of symptoms (156 days/year). However, the mean anxiety scores observed (5.49), fell well below the clinically relevant threshold of 21 required by the Beck Anxiety Inventory. The cohort was stratified to further distinguish individuals with higher pain intensity (NRS>6) and longer symptom duration (>90 days). Although a highly statistically significant difference (p = 0.000) was subsequently observed with respect to pain intensity, in the resulting sub-groups, none such a difference was noted with respect to anxiety levels. Our results indicate that chronic, intense pain and anxiety do not always appear to be related. Explanations for these findings may include that anxiety is not triggered in socially functional individuals, that individual coping strategies have come into play or in some instances that a psychological disorder like alexithymia could be a confounder. More studies are needed to clarify the specific role of anxiety in chronic non-specific musculoskeletal pain before general evidence-driven clinical extrapolations can be made.

A simple and fast method for the determination of selected organohalogenated compounds in serum samples from the general population

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) have been widely used in industry and agriculture. Due to their persistence and bioaccumulation, they were globally spread in the environment and may still be found in environmental and biological media, despite the international restrictions on production and use. The main aim of our study was to develop a simple and fast method suitable for the establishment of the reference values for 15 PCB congeners and 16 OCPs in general population subgroups. A cost- and time-saving screening procedure using gas chromatography coupled with low-resolution mass spectrometry, was improved and validated before application to the analysis of real samples. The overall method was validated including uncertainty measurement. Preliminary field data were collected from 95 volunteers living in two Italian areas. HCB, p,p′-DDE, PCB 153, PCB 138 and PCB 180 were the most frequently detected compounds. Age and residence area were found to be significant variables for the most abundant compounds, while no correlation between serum concentrations and gender was observed. Our results suggest that long-banned substances, including PCBs and the pesticides HCB and DDT's breakdown product, are still detectable in the general population.