SARS-CoV-2 Receptor-Binding Domain IgG Response to AstraZeneca AZD1222 COVID-19 Vaccination, Jamaica.

The Caribbean region is lacking an assessment of the antibody response and side effects experienced after AstraZeneca COVID-19 vaccination (AZD1222). We examined severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike receptor-binding domain (RBD) IgG levels and report the side effects noted in a Jamaican population after AZD1222 vaccination. Median RBD IgG levels for persons without evidence of previous SARS-CoV-2 infection were 43.1 binding international units (bIU)/mL 3 to 7 weeks after the first dose, increasing to 100.1 bIU/mL 3 to 7 weeks after the second dose, and decreasing to 46.9 bIU/mL 16 to 22 weeks after the second dose. The median RBD IgG level 2 to 8 weeks after symptom onset for unvaccinated SARS-CoV-2-infected persons of all disease severities was 411.6 bIU/mL. Common AZD1222 side effects after the first dose were injection site pain, headache, and chills. Most people reported no side effects after the second dose. AZD1222 is widely used across the English-speaking Caribbean, and our study provides evidence for its continued safe and effective use in vaccination programs.

A single baroreceptor unit consists of multiple sensors.

Arterial baroreceptors (BRs) play a vital role in the regulation of the cardiopulmonary system. What is known about how these sensors operate at the subcellular level is limited, however. Until recently, one afferent axon was considered to be connected to a single baroreceptor (one-sensor theory). However, in the lung, a single airway mechanosensory unit is now known to house many sensors (multiple-sensor theory). Here we tested the hypothesis that multiple-sensor theory also operates in BR units, using both morphological and electrophysiological approaches in rabbit aortic arch (in whole mount) labeled with Na+/K+-ATPase, as well as myelin basic protein antibodies, and examined microscopically. Sensory structures presented in compact clusters, similar to bunches of grapes. Sensory terminals, like those in the airways, formed leaf-like or knob-like expansions. That is, a single myelinated axon connected with multiple sensors forming a network. We also recorded single-unit activities from aortic baroreceptors in the depressor nerve in anesthetized rabbits and examined the unit response to a bolus intravenous injection of phenylephrine. Unit activity increased progressively as blood pressure (BP) increased. Five of eleven units abruptly changed their discharge pattern to a lower activity level after BP attained a plateau for a minute or two (when BP was maintained at the high level). These findings clearly show that the high discharge baroreceptor deactivates after over-excitation and unit activity falls to a low discharge sensor. In conclusion, our morphological and physiological data support the hypothesis that multiple-sensory theory can be applied to BR units.

A direct injection technique for investigation of lung sensory properties and reflex functions.

NEW FINDINGS: This article reviews a unique direct injection technique that complements the more conventional right atrial injection and aerosol delivery methods to study sensory and reflex effects of the lung sensors. Used in combination with other methods, this technique should contribute to the pulmonary sensory research. ABSTRACT: The lungs house sensory receptors (sensors) that mediate a variety of sensory and reflex responses to mechanical or chemical changes. These reflexes are mainly carried through pulmonary sympathetic and vagal afferent pathways. The chemosensors in the lung periphery are especially important in pulmonary diseases and their reflex responses have traditionally been studied either by aerosol delivery, which also activates receptors in the central airways, or by right atrial injection, which also activates receptors lying outside the lung. Thus, these techniques may confound the interpretation of sensory function. Our laboratory has developed a direct injection technique to deliver agents into the lung parenchyma, which complements the conventional techniques with some important advantages. This article reviews the technique.

Assessment of commercial SARS-CoV-2 antibody assays, Jamaica.

BACKGROUND: The performance of the Roche Elecsys® Anti-SARS-CoV-2, Abbott Architect SARS-CoV-2 IgM, Abbott Architect SARS-CoV-2 IgG, Euroimmun SARS-CoV-2 IgA, Euroimmun SARS-CoV-2 IgG ELISA, and Trillium IgG/IgM rapid assays was evaluated in Jamaica. METHODS: Diagnostic sensitivities of the assays were assessed by testing serum samples from SARS-CoV-2 PCR-confirmed persons and diagnostic specificity was assessed by testing serum samples collected during 2018-2019 from healthy persons and from persons with antibodies to a wide range of viral infections. RESULTS: Serum samples collected ≥14 days after onset of symptoms, or an initial SARS-CoV-2 RT-PCR positive test for asymptomatics, showed diagnostic sensitivities ranging from 67.9 to 75.0% when including all possible disease severities and increased to 90.0-95.0% when examining those with moderate to critical disease. Grouping moderate to critical disease showed a significant association with a SARS-CoV-2 antibody positive result for all assays. Diagnostic specificity ranged from 96.7 to 100.0%. For all assays examined, SARS-CoV-2 real-time PCR cycle threshold (Ct) values of the initial nasopharyngeal swab sample testing positive were significantly different for samples testing antibody positive versus negative. CONCLUSIONS: These data from a predominantly African descent Caribbean population show comparable diagnostic sensitivities and specificities for all testing platforms assessed and limited utility of these tests for persons with asymptomatic and mild infections.

Association of BMI Changes Between Adolescence and Young Adulthood With Smoking Cessation.

PURPOSE: Weight gain frequently accompanies smoking cessation. This study examined if increasing body mass index (BMI) during the early years of smoking influences quitting by young adulthood. DESIGN: Longitudinal, observational study using in-home interview data. SETTING: National Longitudinal Study of Adolescent and Adult Health (Add Health) 1994 to 2008. SUBJECTS: Nine hundred forty-nine adolescent smokers (12-19 years) followed into young adulthood (20-32 years) through 4 waves of in-home interviews. MEASURES: Outcome variable: Young adult smoking status (yes or no) reported at in-home interviews. Factors: Gender and 4 longitudinal adolescent/young adult BMI trajectories-normal/normal, normal/overweight, normal/obese, and overweight/obese. Covariates: Race-ethnicity, education, household income, and recent quit attempt in adolescence. ANALYSIS: Binary logistic regression analysis. RESULTS: Overall, the rate at which young adults quit smoking was not significantly different based on gender. However, longitudinal changes in BMI trajectory and gender interact to influence young adult smoking status. Women having normal/overweight and normal/obese BMI trajectories were less likely to quit smoking than men. Odds that young adults having some college or post-high school education quit smoking were greater than those with high school education or less. CONCLUSION: At a minimum, providing direct information regarding anticipated weight changes after quitting is indicated in smoking cessation intervention, in addition to strategies to mitigate postcessation weight gain. Faced with weight gain, younger smokers, particularly women, may be more resistant to quitting smoking.

Muscle strengthening activity associates with reduced all-cause mortality in COPD.

Objective Emerging research suggests that aerobic-based physical activity may help to promote survival among chronic obstructive pulmonary disease patients. However, the extent to which engagement in resistance training on survival among chronic obstructive pulmonary disease patients is relatively unknown. Therefore, the purpose of this study was to examine the independent associations of muscle strengthening activities on all-cause mortality among a national sample of U.S. adults with chronic obstructive pulmonary disease. We hypothesize that muscle strengthening activities will be inversely associated with all-cause mortality. Methods Data from the 2003-2006 NHANES were employed, with follow-up through 2011. Aerobic-based physical activity was objectively measured via accelerometry, muscle strengthening activities engagement was assessed via self-report, and chronic obstructive pulmonary disease was assessed via physician-diagnosis. Results Analysis included 385 adults (20 + yrs) with chronic obstructive pulmonary disease, who represent 13.3 million chronic obstructive pulmonary disease patients in the USA. The median follow-up period was 78 months (IQR=64-90), with 82 chronic obstructive pulmonary disease patients dying during this period. For a two muscle strengthening activity sessions/week increase (consistent with national guidelines), chronic obstructive pulmonary disease patients had a 29% reduced risk of all-cause mortality (HR=0.71; 95% CI: 0.51-0.99; P = 0.04). Conclusion Participation in muscle strengthening activities, independent of aerobic-based physical activity and other potential confounders, is associated with greater survival among chronic obstructive pulmonary disease patients.

Association of Longitudinal Changes of Physical Activity on Smoking Cessation Among Young Daily Smokers.

OBJECTIVE: To our knowledge, no longitudinal epidemiological study among daily smokers has examined the effects of physical activity change/ trajectory on smoking cessation. The purpose of this study was to examine the longitudinal effects of changes in physical activity on smoking cessation among a national sample of young (16-24 y) daily smokers. METHODS: Data from the 2003-2005 National Youth Smoking Cessation Survey were used (N = 1178). Using hierarchical agglomerative cluster analysis, 5 distinct self-reported physical activity trajectories over 3 time periods (baseline, 12-month, and 24-month follow-up) were observed, including stable low physical activity, decreasing physical activity, curvilinear physical activity, stable high physical activity, and increasing physical activity. Nicotine dependence (Heaviness of Smoking Index) and demographic parameters were assessed via survey. RESULTS: With stable low physical activity (16.2% quit smoking) serving as the referent group, those in the stable high physical activity (24.8% quit smoking) group had 1.8 greater odds of not smoking at the 24-month follow-up period (odds ratio = 1.81; 95% confidence interval, 1.12-2.91) after adjusting for nicotine dependence, age, gender, race-ethnicity, and education. CONCLUSIONS: Maintenance of regular physical activity among young daily smokers may help to facilitate smoking cessation.

Adolescent and Young Adult Smokers Who Self-Identify as Nonsmokers: Relationship With Cigarette-Related Withdrawal and Cravings.

PURPOSE: Examine the extent to which low-nicotine dependent daily smokers identify themselves as nonsmokers (smoking nonsmokers) over time, and examine the effect of nicotine-related withdrawal symptoms and cravings in predicting self-identified smoking status. DESIGN: Longitudinal. SETTING: National Youth Smoking Cessation Survey 2003-2005. SUBJECTS: One hundred thirty-two adolescents and young adults (16-24 years). MEASURES: A questionnaire was used to assess smoking identity, withdrawal, cravings, and smoking intensity parameters. ANALYSIS: Multivariable logistic regression analysis. RESULTS: Among the 132 smoking nonsmokers at baseline, 45% remained smoking nonsmokers at the 2-year follow-up, with 55% transitioning to smoking (i.e., self-identified as smoking smokers in the interim). After adjustments, participants exhibiting greater restlessness and cravings over time, respectively, had 3.59 (p = .01) and 4.31 (p = .008) greater odds of being a smoking nonsmoker at baseline but then transitioning into a smoking smoker at 2-year follow-up. CONCLUSION: These findings may have implications with respect to interventions emphasizing withdrawal and craving symptoms. Further, given that some youth smokers self-identify as nonsmokers, and do so over time, potential intervention efforts may be pointed toward cognitive-related strategies at improving self-perceptions.

Free-living physical activity characteristics, activity-related air trapping and breathlessness, and utilization of transtheoretical constructs in COPD: A pilot study.

OBJECTIVE: Many patients with Chronic Obstructive Pulmonary Disease (COPD) experience air trapping at rest and during exercise. This study examined the relationship between air trapping and air hunger breathlessness during acute physical activity (PA) engagement. In addition, we examined free-living movement patterns of COPD patients, as well as their utilization of psycho-behavioral factors known to influence PA behavior. METHODS: Ten current or former smokers with COPD (M age=70 years) participated. Baseline pulmonary function measurements were gathered and participants completed a graded exercise test (2, 2.5, and 3 mph; 5 min each). At each stage, air hunger breathlessness was rated using the Multidimensional Dyspnea Profile (MDP). Inspiratory capacity (IC) measurements were also collected to monitor air trapping. Data regarding PA and sedentary behavior was measured over 7 days using accelerometry. RESULTS: The results (mean [SD]) showed air trapping during exercise. IC levels across baseline and the 3 stages, respectively, were 1.66 (.62) L, 1.33 (.52) L, 1.35 (.58) L, and 1.28 (.57) L. A significant difference occurred between baseline and stage 1 (p=.01). Coincident low-to-moderate air-hunger breathlessness was observed across baseline and the 3 stages (Likert scale 0-10): 0.44 (1.01), 1.44 (2.12), 2.33 (2.59), and 2.67 (2.64). Participants utilized few PA-related psycho-behavioral strategies and spent the majority (67.4%) of their waking hours in sedentary behavior, while only engaging 5 min a day of moderate intensity PA and 0 min at vigorous-intensity PA. CONCLUSIONS: These COPD patients were intolerant to low levels of exercise intensity, resulting in little PA engagement, and also utilized few PA-related psycho-behavioral strategies.

Development of a Conceptual Model for Smoking Cessation: Physical Activity, Neurocognition, and Executive Functioning.

PURPOSE: Considerable research has shown adverse neurobiological effects of chronic alcohol use, including long-term and potentially permanent changes in the structure and function of the brain; however, much less is known about the neurobiological consequences of chronic smoking, as it has largely been ignored until recently. In this article, we present a conceptual model proposing the effects of smoking on neurocognition and the role that physical activity may play in this relationship as well as its role in smoking cessation. METHODS: Pertinent published peer-reviewed articles deposited in PubMed delineating the pathways in the proposed model were reviewed. RESULTS: The proposed model, which is supported by emerging research, demonstrates a bidirectional relationship between smoking and executive functioning. In support of our conceptual model, physical activity may moderate this relationship and indirectly influence smoking behavior through physical activity-induced changes in executive functioning. CONCLUSIONS: Our model may have implications for aiding smoking cessation efforts through the promotion of physical activity as a mechanism for preventing smoking-induced deficits in neurocognition and executive function.

Exercise facilitates smoking cessation indirectly via improvements in smoking-specific self-efficacy: Prospective cohort study among a national sample of young smokers.

OBJECTIVE: The purpose of this study was to examine whether exercise is associated with 2-year follow-up smoking status through its influence on smoking-specific self-efficacy. METHODS: Longitudinal data from the 2003-2005 National Youth Smoking Cessation Survey were used, including 1,228 participants (16-24 years). A questionnaire was used to examine baseline exercise levels, baseline smoking-specific self-efficacy, follow-up smoking status, and the covariates. RESULTS: Baseline exercise was associated with baseline self-efficacy (ß=0.04, p<0.001) after adjusting for age category, sex, race-ethnicity, education, and nicotine dependence. Baseline self-efficacy, in turn, was associated with 2-year smoking status (ß=0.23, p<0.001) after adjustments. There was no adjusted direct effect of baseline exercise on 2-year smoking status (ß=0.001, p=0.95); however, the adjusted indirect effect of baseline self-efficacy on the relationship between exercise and 2-year smoking status was significant (ß=0.008, bootstrapped lower and upper CI: 0.002-0.02; p<0.05). The mediation ratio was 0.837, which indicates that smoking-specific self-efficacy mediates 84% of the total effect of exercise on smoking status. CONCLUSIONS: Among daily smokers, exercise may help to facilitate smoking cessation via exercise-induced increases in smoking-specific self-efficacy.

Combined association of physical activity and diet with C-reactive protein among smokers.

BACKGROUND: In the general population, both physical activity and dietary behavior are independently associated with less systemic inflammation, with this relationship less examined among smokers. To our knowledge, no study has examined the combined association of both physical activity and dietary behavior on systemic inflammation among daily smokers, which was the purpose of this study. METHODS: Data from the 2003-2006 NHANES were employed. 810 adult smokers provided C-reactive protein data (CRP; a marker of inflammation), and sufficient physical activity (accelerometry) and dietary data (healthy eating index). RESULTS: The fully adjusted model showed that participants meeting physical activity guidelines and eating a healthy diet (ß = -0.34, p = 0.03) had lower CRP levels when compared to those not engaging in these health behaviors, but only having one health behavior was not a significant predictor of CRP (ß = -0.19, p = 0.14). CONCLUSIONS: Smokers engaging in regular physical activity while consuming a healthy diet demonstrate lower CRP levels than their counterparts. When taken together, these behaviors may mitigate inflammation associated with various chronic diseases, which is of particular importance as very few smokers successfully quit smoking.

Nicotine Dependence, Physical Activity, and Sedentary Behavior among Adult Smokers.

BACKGROUND: Research has previously demonstrated an inverse association between smoking status and physical activity; however, few studies have examined the association between nicotine dependence and physical activity or sedentary behavior. AIM: This study examined the association between nicotine dependence and accelerometer-determined physical activity and sedentary behavior. MATERIALS AND METHODS: Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used. A total of 851 adult (≥20 years) smokers wore an accelerometer for ≥4 days and completed the Fagerstrom Test for Nicotine Dependence scale. Regression models were used to examine the association between nicotine dependence and physical activity/sedentary behavior. RESULTS: After adjusting for age, gender, race-ethnicity, poverty level, hypertension, emphysema, bronchitis, body mass index (BMI), cotinine, and accelerometer wear time, smokers 50 + years of age with greater nicotine dependence engaged in more sedentary behavior (ß = 11.4, P = 0.02) and less light-intensity physical activity (ß = -9.6, P = 0.03) and moderate-to-vigorous physical activity (MVPA; ß = -0.14, P = 0.003) than their less nicotine dependent counterparts. CONCLUSION: Older adults who are more nicotine dependent engage in less physical activity (both MVPA and light-intensity) and more sedentary behavior than their less nicotine dependent counterparts.

Physical activity and nicotine dependence among a national sample of young U.S. adults who smoke daily: evaluation of cross-sectional and longitudinal associations to determine which behavior drives this relationship.

The association between nicotine dependence and physical activity (PA) is relatively unknown. No study has concurrently examined the cross-sectional and longitudinal associations between PA and nicotine dependence, which was the primary purpose of this study. A secondary purpose was to examine how well nicotine dependence and PA behavior track over a two-year period. Data from the 2003-2005 National Youth Smoking Cessation Survey (NYSCS) were used, with young adults (18-24 yrs; n=1168) being followed over a two-year period. Physical activity was assessed using a questionnaire and nicotine dependence was assessed using the modified Fagerstrom Test for Nicotine Dependence scale. This study identified three notable findings: 1) baseline PA and nicotine dependence demonstrated a bidirectional, cross-sectional association (e.g., ß=-0.23; 95% CI: -0.44 to -0.02; p=0.02); 2) when examined longitudinally, nicotine dependence influenced PA (OR=0.90; 95% CI: 0.82-0.99; p=0.04), but there was no evidence of the reverse pathway (i.e., PA influencing 2-year follow-up smoking status [OR=0.95; 95% CI: 0.66-1.39; p=0.82) or nicotine dependence (ß=0.05; 95% CI: -0.14 to 0.24, p=0.61]); and 3) both PA (OR=3.52, 95% CI: 2.68-4.69; p<0.001) and nicotine dependence (ß=0.52; 95% CI: 0.46-0.58, p<0.001) tracked relatively well over a two-year period during early adulthood. These findings suggest that both behaviors (physical activity and nicotine dependence) track over time, but nicotine dependence appears to be driving the cross-sectional relationship between nicotine dependence and physical activity, as opposed to the reverse pathway.

Nicotine dependence and transitional shifts in exercise behavior among young U.S. adult smokers.

OBJECTIVE: The aim of this study is to examine the association between nicotine dependence and longitudinal exercise transitional shift patterns among young U.S. adult daily smokers. METHODS: Data from the 2003-2005 National Youth Smoking Cessation Survey was used, which is a longitudinal study over a two year period. Participants included 1168 US adult daily smokers (18-24years). Nicotine dependence was assessed using the modified Fagerstrom Test for Nicotine Dependence. Four transitional shift patterns were created based on meeting current exercise guidelines; stable inactive (inactive across time), activity relapsers (starts out active and then becomes inactive), activity adopters (inactive and then becomes active), and stable active (active across time). RESULTS: After adjustments, for every 1-unit increase in baseline nicotine dependence, participants had 16% (OR=1.16, p=0.01) greater odds of being in the stable inactive group compared to the stable active group. CONCLUSIONS: Nicotine dependence appears to play an important role in shaping longitudinal exercise patterns among young U.S. adult smokers.

Longitudinal examination of predictors of smoking cessation in a national sample of U.S. adolescent and young adult smokers.

INTRODUCTION: To better inform the development of smoking cessation programs for adolescents and young adults, a prospective study was employed to systematically examine behavioral, demographic, health, and psychosocial determinants of smoking cessation. METHODS: Data from the 2003-2005 National Youth Smoking Cessation Survey were used. Of 2,582 smokers aged 16-24 years sampled, 1,354 provided complete baseline telephone interview data on the study variables, and their self-reported smoking status at 2-year follow-up was known (currently smoking vs. not smoking). Multivariable logistic regression analysis was employed to examine independent predictors of smoking status (outcome variable) at the 2-year follow-up period. RESULTS: Four of 5 participants remained smokers after 2 years. Of the high nicotine dependence smokers, 90% remained smokers at follow-up; of the low nicotine dependence smokers, 77% remained smokers at follow-up. Higher nicotine dependence smokers started smoking earlier in life (13.2 vs. 14.3 years; p < .05). Similarly, those not smoking at the 2-year follow-up period started smoking later in life than those still smoking (14.5 vs. 13.7 years). Along with nicotine dependence, various psychosocial and demographic variables at baseline predicted smoking status at the 2-year follow-up period. CONCLUSIONS: Identifiable demographic and psychosocial factors influence smoking behavior among U.S. adolescents and young adults. Even low nicotine dependence is a strong predictor of follow-up smoking behavior. This, coupled with the early smoking age of high nicotine dependence smokers, underscores the importance of early nicotine avoidance among youth.

Physical activity moderates the association between nicotine dependence and depression among U.S. smokers.

PURPOSE: Research demonstrates that nicotine dependence and depression are associated and that physical activity is effective in reducing depression symptoms. However, our understanding of the potential beneficial effects of physical activity on depression in current smokers is more limited. The purpose of this study was to examine whether physical activity moderates the association between nicotine dependence and depression in U.S. smokers. DESIGN: Cross-sectional. SETTING: National Health and Nutrition Examination Survey 2005-2006. SUBJECTS: Four hundred forty-one current adult smokers. MEASURES: Participants wore an accelerometer for at least 4 days and completed questionnaires to assess nicotine dependence and depression. ANALYSIS: Effect modification and statistical interaction models were used. RESULTS: Both models were significant. With regard to the statistical interaction model, and after controlling for age, gender, race/ethnicity, education, comorbidity index, homocysteine, cotinine, total cholesterol, sedentary behavior, and vitamins C, D, and E, objectively measured physical activity moderated the association between nicotine dependence and depression (interaction variable: odds ratio = 3.43; 95% confidence interval: 1.02-11.51; p = .04). CONCLUSION: In this national sample of current smokers, physical activity moderated the association between nicotine dependence and depression. These results suggest that those individuals with nicotine dependence and who are less physically active are more likely to be depressed than what would be expected on the basis of the individual effects of nicotine and physical inactivity separately.

Association between physical activity and inflammatory markers among U.S. adults with chronic obstructive pulmonary disease.

PURPOSE: Chronic obstructive pulmonary disease (COPD) may cause not only inflammation in the lungs but also systemic effects. One potential strategy to reduce systemic inflammation and attenuate disease progression is physical activity (PA). However, no nationally representative studies, to our knowledge, have examined the association between objectively measured physical activity and inflammation among those with COPD. DESIGN: Cross-sectional. SETTING: National Health and Nutrition Examination Survey 2003-2006. SUBJECTS: Two hundred thirty-eight former or current smokers with self-reported COPD who had complete data on study variables. MEASURES: Participants wore an accelerometer for ≥4 days to assess light-intensity PA (LPA), moderate-to-vigorous PA (MVPA), and total physical activity (TPA); completed questionnaires to assess self-reported COPD and smoking status; and had their blood taken to assess white blood cell (WBC) and neutrophil levels. ANALYSIS: Multivariable linear regression analysis was used. RESULTS: LPA (ß = -.0004), MVPA (ß = -.04), and TPA (ß = -.0004) were significantly inversely associated with WBC level. Similarly, LPA (ß = -.001) and TPA (ß = -.001) were significantly inversely associated with neutrophils; however, MVPA was marginally associated with neutrophils (ß = -.05; p =.06). CONCLUSION: These analyses demonstrate an inverse association between objectively measured PA and inflammation among current or former smokers with COPD. If these findings are confirmed elsewhere, then PA among those with COPD may serve as an anti-inflammatory strategy to possibly decrease cardiovascular and metabolic disease occurrence.

Association between physical activity and major depressive disorder among current or former smokers with pulmonary disease.

OBJECTIVE: To examine the association between physical activity and major depressive disorder (MDD) in a nationally representative sample of current or former smokers with pulmonary impairments. METHODS: The analyzed sample from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 included 536 adults who indicated that they were current or former smokers, had at least mild pulmonary impairment (FEV1/FVC<0.70), and provided depression and physical activity data. RESULTS: After controlling for asthma status, pulmonary impairment, age, poverty-to-income ratio (PIR), education, gender, marital status, body mass index (BMI), cotinine, comorbidity index, race-ethnicity, and smoking status, those who met physical activity guidelines had a 59% (odds ratio (OR)=0.41; 95% confidence interval (CI): 0.18-0.94) lower odds of having MDD. Using multivariate linear regression with depression symptoms as the outcome variable, and after adjustments, physical activity was inversely associated with depression symptoms in a dose-response manner; lowest tertile was the referent group, middle tertile coefficient: -1.06 (95% CI: -1.98 to -0.14), and highest tertile coefficient: -1.10 (95% CI: -1.84 to -0.34). CONCLUSIONS: Physical activity inversely associates with MDD in adults with pulmonary impairments, and does so in a dose-response manner. This suggests that individuals with pulmonary impairments should be encouraged to engage in enjoyable, safe forms of physical activity in a progressive manner.

Do nicotine intake and acute heart rate response to smoking rank nicotine dependence the same?

In this study, two proposed scales of nicotine dependence were compared: self-administered nicotine intake and acute heart rate sensitivity to smoking. Our aim was to determine if these nicotine dependence scales would rank relative dependence the same in a sample of 15 male chronic smokers who smoked their first cigarette in the morning after overnight abstinence. Heart rate and plasma nicotine levels were measured before and 5, 10, 15, and 30 min after smoking. The results of this pilot study suggest that heart rate sensitivity and nicotine intake do not have a direct linear relationship, but rather a curvilinear relationship. A marked increase in heart rate sensitivity was observed at approximately the 70th percentile of nicotine intake.