Predictors of fatigue in healthy young adults: moderating effects of cigarette smoking and gender

Musculoskeletal crosstalk in chronic obstructive pulmonary disease and comorbidities: Emerging roles and therapeutic potentials

Chronic Obstructive Pulmonary Disease (COPD) is a multifaceted respiratory disorder characterized by progressive airflow limitation and systemic implications. It has become increasingly apparent that COPD exerts its influence far beyond the respiratory system, extending its impact to various organ systems. Among these, the musculoskeletal system emerges as a central player in both the pathogenesis and management of COPD and its associated comorbidities. Muscle dysfunction and osteoporosis are prevalent musculoskeletal disorders in COPD patients, leading to a substantial decline in exercise capacity and overall health. These manifestations are influenced by systemic inflammation, oxidative stress, and hormonal imbalances, all hallmarks of COPD. Recent research has uncovered an intricate interplay between COPD and musculoskeletal comorbidities, suggesting that muscle and bone tissues may cross-communicate through the release of signalling molecules, known as "myokines" and "osteokines". We explored this dynamic relationship, with a particular focus on the role of the immune system in mediating the cross-communication between muscle and bone in COPD. Moreover, we delved into existing and emerging therapeutic strategies for managing musculoskeletal disorders in COPD. It underscores the development of personalized treatment approaches that target both the respiratory and musculoskeletal aspects of COPD, offering the promise of improved well-being and quality of life for individuals grappling with this complex condition. This comprehensive review underscores the significance of recognizing the profound impact of COPD on the musculoskeletal system and its comorbidities. By unravelling the intricate connections between these systems and exploring innovative treatment avenues, we can aspire to enhance the overall care and outcomes for COPD patients, ultimately offering hope for improved health and well-being.

Exploring causal effects of smoking and alcohol related lifestyle factors on self-report tiredness: A Mendelian randomization study

Self-reported tiredness or low energy, often referred to as fatigue, has been linked to lifestyle factors, although data from randomized-controlled trials are lacking. We investigate whether modifiable lifestyle factors including smoking and alcohol intake related exposures (SAIEs) are causal factors for fatigue using Mendelian randomization (MR). A two-sample MR study was performed by using genome-wide association summary results from UK Biobank (UKBB), and each of the sample size is more than 100,000. We used the inverse variance weighted method, and sensitivity analyses (MR Egger, weighted median, penalized median estimators, and multivariable MR) to account for pleiotropy. The two-sample MR analyses showed inverse causal effect of never-smoking status and positive effect of current smoking status on the risk of fatigue. Similarly, genetically predicted alcoholic intake was positively associated with fatigue. The results were consistent across the different MR methods. Our Mendelian randomization analyses do support that the cessation of smoking and alcohol can decrease the risk of fatigue, and limit alcohol intake frequency can also reduce the risk.

Dimensionality, psychometric properties, and population-based norms of the Turkish version of the Chalder Fatigue Scale among adults

BACKGROUND

Fatigue is emerging as a major public health problem that is highly associated with poor health-related quality of life and disability. Among adults, fatigue has become increasingly common because of workload or lifestyle changes. This study aimed to cross-culturally adapt the Chalder Fatigue Scale (CFS) into Turkish, to investigate its psychometric properties, and to establish normative data in healthy adults by age and gender.

METHODS

The validity of the CFS was tested with a total sample of 476 healthy adults aged 20-40 years (264 males and 212 females) and test-retest/measurement error analyses were performed with 161 participants (94 males and 67 females). The test-retest reliability was examined using the intraclass correlation coefficient (ICC), and internal consistency was determined using Cronbach's α-coefficient. Predictive validity was assessed using the Receiver Operating Characteristic to validate the cut-off value of the CFS for non-fatigued and fatigued participants. Factor analyses and hypothesis testing were conducted to assess construct validity. Hypothesis testing examined convergent and known-group validity by testing 14 predefined hypotheses.

RESULTS

The mean (SD) and median (25-75%) CFS scores were 10.7 (4.9) and 11 (7-14) for the total sample (n = 476). The cut-off point for CFS was set at ≥ 12 with a sensitivity of 65.8% and a specificity of 85.9%. The CFS provided evidence of excellent fit of the two-factor structure (CFI = 0.963, RMSEA = 0.06, SRMR = 0.02). There was evidence of strong internal consistency demonstrated by Cronbach's α = 0.863 and good test-retest reliability by ICC = 0.76. Thirteen out of 14 hypotheses (92.9%) were confirmed and the scale showed low to moderate correlation with other measurement instruments (r = 0.31-0.51).

CONCLUSIONS

The CFS has been shown to be a reliable and valid instrument that can be used in various populations for the assessment of fatigue.

LEVEL OF EVIDENCE

Level II.

Resistance training prevents damage to the mitochondrial function of the skeletal muscle of rats exposed to secondary cigarette smoke

AIM

To analyze the consumption of oxygen and to quantify the mitochondrial respiratory chain proteins (OXPHOS) in the gastrocnemius muscle of rats exposed to cigarette smoke and/or RT practitioners.

MAIN METHODS

Wistar rats were divided into groups: Control (C), Smoker (S), Exercise (E) and Exercise Smoker (ES). Groups F and ES were exposed to the smoke of 4 cigarettes for 30 min, 2× a day, 5× a week, for 16 weeks. Groups E and ES performed four climbs with progressive load, 1× per day, 5× per week, for 16 weeks. The gastrocnemius muscle was collected for analysis of OXPHOS content and oxygen consumption. Groups S (vs. C) and ES (vs. C and E) showed lower body weight gain when observing the evolution curve.

KEY FINDINGS

The S rats showed a reduction in the NDUFB8 proteins of complex 1, SDHB of complex 2, MTC01 of complex 4 and ATP5A of complex 5 (ATP Synthase) compared to Group C. Additionally, S rats also showed increased consumption of O2 in Basal, Leak, Complex I and I/II combined measures compared to the other groups, suggesting that the activity of the mitochondria of these animals increased in terms of coupling and uncoupling parameters.

SIGNIFICANCE

Our data suggest that exposure to cigarette smoke for 16 weeks is capable of causing impairment of mitochondrial function with reduced expression of respiratory chain proteins in skeletal muscle. However, the RT was effective in preventing impairment of mitochondrial function in the skeletal muscle of rats exposed to secondary cigarette smoke.

Acute aerobic exercise to recover from mental exhaustion - a randomized controlled trial

PURPOSE

Prolonged periods of intense cognitive activity lead to a state of mental exhaustion. While widespread strategies to recover from mental exhaustion (i.e., watching TV) are non-effective, aerobic exercise seems to be a promising approach. This can be explained by the acute and chronic aerobic exercise-induced benefits on the central nervous system.

METHODS

This study investigated the potential of a single bout of moderate aerobic exercise (65-75% of each participants' individual V˙O2peak) to recover from experimentally induced mental exhaustion. A randomized controlled trial on healthy adults (N = 99) was conducted. They performed 60 min of a cognitively demanding test battery, in order to induce mental exhaustion. Subsequently, they were randomized to one of three treatments: 30 min of moderate aerobic exercise on a cycle ergometer, 30 min of a simple lower body stretching routine (= active control treatment) or watching a popular sitcom (= passive control treatment). Cognitive flexibility performance, mood, tiredness, restlessness, self-perceived cognitive capacity, and motivation were assessed before and after treatment.

RESULTS

The empirical results showed that moderate aerobic exercise led to a better recovery for cognitive flexibility (mean difference divided by pooled standard deviation, Cohen's d= 0.737), mood (d= 0.405), tiredness (d= 0.480), self-perceived cognitive capacity (d= 0.214), and motivation (d= 0.524) compared to active control treatment. Moderate aerobic exercise was also more effective than passive control treatment (d= 0.102 - 0.286) with the exemption of tiredness (d= 0.015) and restlessness (d = -0.473).

CONCLUSION

In conclusion, this study suggests that a single bout of acute aerobic exercise supports regeneration of cognitive flexibility performance and of subjective well-being. This holds true not just compared to artificial active control treatment but also compared to widespread leisure time activity, namely watching TV.

Apocynin prevents cigarette smoking-induced loss of skeletal muscle mass and function in mice by preserving proteostatic signalling

Background and Purpose

Skeletal muscle dysfunction is a major comorbidity of chronic obstructive pulmonary disease (COPD). This type of muscle dysfunction may be a direct consequence of oxidative insults evoked by cigarette smoke (CS) exposure. The present study examined the effects of a potent Nox inhibitor and reactive oxygen species (ROS) scavenger, apocynin, on CS‐induced muscle dysfunction.

Experimental Approach

Male BALB/c mice were exposed to either room air (sham) or CS generated from nine cigarettes per day, 5 days a week for 8 weeks, with or without the coadministration of apocynin (5 mg·kg⁻¹, i.p.). C2C12 myotubes exposed to either hydrogen peroxide (H₂O₂) or water‐soluble cigarette smoke extract (CSE) with or without apocynin (500 nM) were used as an experimental model in vitro.

Key Results

Eight weeks of CS exposure caused muscle dysfunction in mice, reflected by 10% loss of muscle mass and 54% loss of strength of tibialis anterior which were prevented by apocynin administration. In C2C12 myotubes, direct exposure to H₂O₂ or CSE caused myofibre wasting, accompanied by ~50% loss of muscle‐derived insulin‐like growth factor (IGF)‐1 and two‐fold induction of Cybb, independent of cellular inflammation. Expression of myostatin and MAFbx, negative regulators of muscle mass, were up‐regulated under H₂O₂ but not CSE conditions. Apocynin treatment abolished CSE‐induced Cybb expression, preserving muscle‐derived IGF‐1 expression and signalling pathway downstream of mammalian target of rapamycin (mTOR), thereby preventing myofibre wasting.

Conclusion and Implications

Targeted pharmacological inhibition of Nox‐derived ROS may alleviate the lung and systemic manifestations in smokers with COPD.

Emotion dysregulation, fatigue, and electronic cigarette expectancies

Emotion dysregulation and the experience of fatigue have both been linked to the maintenance of substance use. However, limited empirical data has evaluated individual differences in these constructs in terms of e-cigarette use expectancies. The present study examined a theoretically relevant model focused on whether the experience of more severe fatigue explains, in part, the relation between individual differences in emotion dysregulation and positive and negative e-cigarette expectancies among 525 adult e-cigarette users (50.9% female, Mage = 35.25 years, SD = 10.10). It was hypothesized that emotion dysregulation, via fatigue severity, would significantly predict greater positive and negative e-cigarette expectancies, which was examined in two separate mediation models. Fatigue severity significantly explained, in part, the relation between emotion dysregulation and positive (b = 0.02, CI [0.01, 0.02]) and negative expectancies of e-cigarette use (b = 0.02, 95% CI [0.02, 0.03]). The current findings suggest that the experience of fatigue helps explain the relation between emotion dysregulation and positive and negative e-cigarette expectancies among adult e-cigarette users. Future work is needed to explicate how reducing fatigue severity in the context of emotion dysregulation may change expectancies about e-cigarette expectancies.

Sarcopenia in patients with chronic obstructive pulmonary disease: A study of prevalence and associated factors in Western Greek population

Background:

Chronic obstructive pulmonary disease (COPD) is associated with a progressive loss of muscle mass and function and a systemic inflammatory process that can cause sarcopenia.

Objective:

The objective of this study is to estimate the prevalence rate of sarcopenia in COPD patients and to determine the factors associated with sarcopenic patients living in Western Greece.

Methods:

European Working Group on Sarcopenia in Older People criteria were applied to 69 outpatients with stable COPD. Body composition, exercise capacity, functional performance, physical activity, and health status were also assessed. COPD disease severity (COPD stage) was evaluated with the Global Initiative for chronic obstructive lung disease. The study protocol was approved by the Ethical Committee of the Technological Educational Institute of Western Greece.

Results:

The sample comprised 69 patients (59 women and 10 men), with a mean age of 71.33 ± 7.48 years. The prevalence of sarcopenia was 24.6% (n = 17). A high percentage (82.6%; n = 57) of the 69 Greek participants did not perform any regular exercise. The findings of this study demonstrated that sarcopenia was positively associated with COPD, age, body mass index, skeletal muscle mass, hand grip strength, and 4 m test.

Conclusions:

In conclusion, there is a 24.6% prevalence of sarcopenia in patients with COPD. Further research with larger samples would be indicated to clarify the precise association of specific characteristics of patients with sarcopenia and COPD.

Sleep Disturbances in Young Adults with Childhood Traumatic Brain Injury: Relationship with Fatigue, Depression, and Quality of Life

OBJECTIVE

This study assessed the consequences of childhood traumatic brain injury (TBI) on sleep, fatigue, depression, and quality of life (QoL) outcomes and explored the relationships between these variables at 20 years following childhood TBI.

PARTICIPANTS

We followed up 54 young adults with mild, moderate, and severe TBI, and 13 typically developing control (TDC) participants, recruited at the time of TBI.

METHODS

Sleep was assessed with the Pittsburgh Sleep Quality Index and actigraphy.

RESULTS

At 20 years postinjury, results showed no significant difference between whole TBI group and TDC participants on subjective sleep quality; however, the moderate TBI group reported significantly poorer subjective sleep quality compared to those with severe TBI. Poorer subjective sleep was associated with increased symptoms of fatigue, depression, and poorer perceptions of General Health in the TBI group. Actigraphic sleep efficiency, fatigue, depression, and QoL outcomes were not significantly different between TBI and TDC or among TBI severity groups.

CONCLUSIONS

These preliminary findings underscore associations between subjective sleep disturbance, fatigue, depression, and QoL in this TBI sample, and mostly comparable outcomes in sleep, fatigue, depression, and QoL between the TBI and TDC groups. Further research is required to clarify these findings.

The acute effects of cigarette smoke exposure on muscle fiber type dynamics in rats

Reduced exercise capacity is common in people with chronic obstructive pulmonary diseases (COPD) and chronic smokers and is suggested to be related to skeletal muscle dysfunction. Previous studies using human muscle biopsies have shown fiber-type shifting in chronic smokers particularly those with COPD. These results, however, are confounded with aging effects because people with COPD tend to be older. In the present study, we implemented an acute 7-day cigarette smoke-exposed model using Sprague-Dawley rats to evaluate early effects of cigarette smoking on soleus muscles. Rats (n = 5 per group) were randomly assigned to either a sham air (SA) or cigarette smoking (CS) groups of three different concentrations of total particulate matters (TPM) (CS_TPM2.5, CS_TPM5, CS_TPM10). Significantly lower percentages of type I and higher type IIa fiber were detected in the soleus muscle in CS groups when compared with SA group. Of these, only CS_TMP10 group exhibited significantly lower citrate synthase activity and higher muscle tumor necrosis factor-α level than that of SA group. Tumor necrosis factor-α level was correlated with the percentage of type I and IIa fibers. However, no significant between-group differences were found in fiber cross-sectional area, physical activities, or lung function assessments. In conclusion, acute smoking may directly trigger the onset of glycolytic fiber type shift in skeletal muscle independent of aging.

The effects of oral nicotine administration and abstinence on sleep in male C57BL/6J mice

BACKGROUND

Sleep disturbances are common in smoking cessation attempts and are predictive of relapse. Despite this knowledge, there is no established animal model to study the effect of nicotine abstinence on sleep and EEG parameters.

OBJECTIVES

The present study was conducted to characterize sleep and wakefulness in male C57BL/6J mice during periods of oral nicotine administration and abstinence.

METHODS

Male C57BL/6J mice were implanted with EEG/EMG recording devices. EEG/EMG data were recorded continuously for a period of 4 weeks. At the beginning of week 2, 200 μg/ml of nicotine was added to the 0.2% saccharin vehicle drinking solution. Following a 2-week period of oral nicotine administration, abstinence was initiated by excluding the nicotine from the 0.2% saccharin vehicle drinking solution. EEG/EMG were analyzed at pre-nicotine baseline, during nicotine administration, and on days 1, 2, and 5 of abstinence from nicotine.

RESULTS

Oral nicotine administration decreased total sleep time during the active phase, consistent with the stimulant actions of nicotine. In contrast, NREM sleep quantity was increased during the active phase on nicotine abstinence day 1 and REM sleep was decreased during days 2 and 5 of abstinence. Further, sleep fragmentation was increased during the inactive phase on all days of abstinence. Oral nicotine administration and abstinence from nicotine also altered EEG relative power frequencies during the inactive and active phase.

CONCLUSIONS

Both oral nicotine administration and abstinence lead to sleep disturbances in mice. Similarities between this model and human reports on the effect of nicotine/nicotine withdrawal on sleep support its utility in examining the molecular mechanisms that modulate the relationship between sleep, nicotine, and nicotine abstinence/withdrawal.

Muscle Dysfunction in Smokers and Patients With Mild COPD: A SYSTEMATIC REVIEW

PURPOSE

To describe and discuss the available evidence in the literature concerning muscle function and the association between smoking and muscle dysfunction in smokers and patients with mild chronic obstructive pulmonary disease (COPD).

METHODS

The literature search involved the following databases: PubMed, Pedro, CINAHL, Cochrane Library, Lilacs, and EMBASE. Studies were included if they investigated muscle strength and/or endurance and/or cross-sectional area (CSA) in smokers and/or patients with COPD classified as Global Initiative for Obstructive Lung Disease (GOLD) I and without lung cancer. Two authors screened and identified the studies for inclusion.

RESULTS

Eighteen studies were identified. Some studies found lower values in a variety of muscle strength variables in smokers compared with nonsmoking controls, whereas others found similar values between these groups. When comparing patients with COPD classified as GOLD I with smokers, COPD patients showed lower muscle strength. Two studies found no differences in muscle CSA between smokers compared with nonsmoking controls. Some preliminary evidence also shows that patients with COPD classified as GOLD I had lower CSA in comparison with smokers.

CONCLUSION

Results concerning muscle dysfunction in smokers are divergent, since some studies have shown worse results in a variety of muscle strength variables in smokers compared with nonsmoking controls, whereas other studies have not. Moreover, there is rather preliminary evidence indicating worse muscle dysfunction and lower CSA in patients with mild COPD in comparison with healthy (or non-COPD) smokers.

An integrative review of the theory of unpleasant symptoms

AIMS

The aim of this study was to explore how the theory of unpleasant symptoms (TOUS) has been used in the methodological design and analysis of symptom research.

DESIGN

An integrative review, using Whittemore and Knafl's approach.

DATA SOURCES

Searches were conducted between 26 January-10 February 2018. Databases included CINAHL Complete, PubMed, Proquest Nursing and Allied Health Source, Health Source: Nursing/Academic Edition, Academic Search Complete and Google Scholar.

REVIEW METHODS

A systematic approach to searching, screening and analysing the literature was applied. The matrix method, content analysis, constant comparison, counting and clustering were used.

RESULTS

Sixty-four records were included. Most studies were quantitative, cross-sectional, instrument-based and conducted in the USA. Various symptoms and patient populations were represented and each of the TOUS concepts were explored.

CONCLUSION

Although the theory has a role to play in furthering symptom science, attention should be paid to the areas of the model and of symptom research that have received less attention. More complex statistical approaches and big data will help to illuminate symptom experiences. Additional focus on intervention studies and all symptom dimensions will help to advance symptom science research.

IMPACT

This review is the first to provide a comprehensive, systematic summary of the uses of the TOUS across the research literature to date. This theory is a diverse, holistic middle-range theory capable of being applied to multiple symptoms and populations. Researchers should consider using the theory as a conceptual framework for studies to advance symptom science and explore symptoms holistically.

Nutritional status and muscle dysfunction in chronic respiratory diseases: stable phase versus acute exacerbations

Nutritional abnormalities are frequent in different chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), bronchiectasis, cystic fibrosis (CF), interstitial fibrosis and lung cancer, having important clinical consequences. However, nutritional abnormalities often remained underdiagnosed due to the relative lack of awareness of health professionals. Therefore, systematic anthropometry or even better, assessment of body composition, should be performed in all patients with chronic respiratory conditions, especially following exacerbation periods when malnutrition becomes more accentuated. Nutritional abnormalities very often include the loss of muscle mass, which is an important factor for the occurrence of muscle dysfunction. The latter can be easily detected with the specific assessment of muscle strength and endurance, and also negatively influences patients' quality of life and prognosis. Both nutritional abnormalities and muscle dysfunction result from the interaction of several factors, including tobacco smoking, low physical activity-sedentarism, systemic inflammation and the imbalance between energy supply and requirements, which essentially lead to a negative balance between protein breakdown and synthesis. Therapeutic approaches include improvements in lifestyle, nutritional supplementation and training. Anabolic drugs may be administered in some cases.

Waterpipe use in adolescents in Northern Sweden: Association with mental well-being and risk and health behaviours

AIMS

There is a lack of studies examining the association between waterpipe smoking and mental well-being among adolescents. This study sought to determine whether waterpipe smoking is associated with mental well-being and other risk and health behaviours in adolescents.

METHODS

A questionnaire was distributed to 1006 adolescents in grades 9-12 (with a response rate of >95%), containing questions on measures of stress, mental energy and sleep. In addition, the questionnaire assessed risk and health behaviours, including use of a waterpipe, cigarettes, e-cigarettes, snus, alcohol, narcotics, gambling and exercise. Logistic regression was used to assess factors associated with waterpipe use.

RESULTS

Thirty-seven per cent ( n=371) of the participants had used a waterpipe at some point. Waterpipe use was associated with lower mental energy (odds ratio [OR] = 0.90, 95% confidence interval [CI] 0.81-0.99), higher stress (OR = 1.10, 95% CI 1.02-1.20) and use of cigarettes (OR = 3.82, 95% CI 2.33-6.03), e-cigarettes (OR = 3.26, 95% CI 2.12-4.99), snus (OR = 2.29, 95% CI 2.12-4.99), alcohol (OR = 1.92, 95% CI 1.07-3.44) and narcotics (OR = 3.64, 95% CI 1.75-7.58). Waterpipe use was not significantly associated with gambling, exercise or sleep quality.

CONCLUSIONS

Waterpipe use in adolescents is associated with worse mental well-being, as well as use of other nicotine products, alcohol and narcotics. Prospective studies are needed to delineate causal and temporal relationships further between waterpipe use and mental well-being and its relationship to other risky behaviours in order to design effective prevention programs.

A survey of the prevalence of fatigue, its precursors and individual coping mechanisms among U.S. manufacturing workers

Advanced manufacturing has resulted in significant changes on the shop-floor, influencing work demands and the working environment. The corresponding safety-related effects, including fatigue, have not been captured on an industry-wide scale. This paper presents results of a survey of U.S. manufacturing workers for the: prevalence of fatigue, its root causes and significant factors, and adopted individual fatigue coping methods. The responses from 451 manufacturing employees were analyzed using descriptive data analysis, bivariate analysis and Market Basket Analysis. 57.9% of respondents indicated that they were somewhat fatigued during the past week. They reported the ankles/feet, lower back and eyes were frequently affected body parts and a lack of sleep, work stress and shift schedule were top selected root causes for fatigue. In order to respond to fatigue when it is present, respondents reported coping by drinking caffeinated drinks, stretching/doing exercises and talking with coworkers. Frequent combinations of fatigue causes and individual coping methods were identified. These results may inform the design of fatigue monitoring and mitigation strategies and future research related to fatigue development.

iLid: Low-power Sensing of Fatigue and Drowsiness Measures on a Computational Eyeglass

The ability to monitor eye closures and blink patterns has long been known to enable accurate assessment of fatigue and drowsiness in individuals. Many measures of the eye are known to be correlated with fatigue including coarse-grained measures like the rate of blinks as well as fine-grained measures like the duration of blinks and the extent of eye closures. Despite a plethora of research validating these measures, we lack wearable devices that can continually and reliably monitor them in the natural environment. In this work, we present a low-power system, iLid, that can continually sense fine-grained measures such as blink duration and Percentage of Eye Closures (PERCLOS) at high frame rates of 100fps. We present a complete solution including design of the sensing, signal processing, and machine learning pipeline; implementation on a prototype computational eyeglass platform; and extensive evaluation under many conditions including illumination changes, eyeglass shifts, and mobility. Our results are very encouraging, showing that we can detect blinks, blink duration, eyelid location, and fatigue-related metrics such as PERCLOS with less than a few percent error.

Modifiable Factors Associated With Aging Phenotypes Among Adult Survivors of Childhood Acute Lymphoblastic Leukemia

PURPOSE

Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for low bone mineral density (BMD) and frail health, outcomes potentially modifiable by altering health behaviors and/or treating endocrine abnormalities. We evaluated associations between lifestyle and hormonal deficits with risk of low BMD and frailty among survivors of ALL.

PATIENTS AND METHODS

Participants included 862 survivors of ALL (median age, 31.3 years [range, 18.4 to 59.7 years]) enrolled in the St Jude Lifetime Cohort study. Bone density was measured using quantitative computed tomography of L1 through L2 vertebrae; low BMD was defined as an age- and sex-standardized z score < -1. The presence of frailty or prefrailty was defined as having at least two of the following: low muscle mass, self-reported exhaustion, low energy expenditure, slow walking speed, and weakness. Hormonal deficiencies were determined according to medical history, medications, and laboratory findings (insulin-like growth factor 1, follicle-stimulating hormone, luteinizing hormone, and testosterone levels). Logistic regression was used to examine associations between lifestyle (smoking, alcohol consumption, and activity levels) and deficiencies in growth hormone (GHD) and/or sex steroids with low BMD and frailty.

RESULTS

Thirty percent of survivors met criteria for low BMD, and 18.6% for frailty/prefrailty. After adjusting for body mass index, low BMD was associated with GHD (odds ratio [OR], 1.59; 95% CI, 1.02 to 2.13) and current smoking (OR, 1.71; 95% CI, 1.02 to 2.85) among men; and GHD (OR, 2.18; 95% CI, 1.26 to 3.78) and moderate alcohol consumption (OR, 2.09; 95% CI, 1.14 to 3.83) among women. After adjusting for current age, the odds of frailty/prefrailty were increased among men with GHD (OR, 2.97; 95% CI, 1.56 to 5.67) and those who smoked (OR, 3.26; 95% CI, 1.65 to 6.43); there were no significant associations among women.

CONCLUSION

The findings suggest that survivors of ALL should receive counseling regarding lifestyle and undergo screening for hormonal deficits to minimize the risk of low BMD and frailty.

Muscle dysfunction in chronic obstructive pulmonary disease: update on causes and biological findings

Respiratory and/or limb muscle dysfunction, which are frequently observed in chronic obstructive pulmonary disease (COPD) patients, contribute to their disease prognosis irrespective of the lung function. Muscle dysfunction is caused by the interaction of local and systemic factors. The key deleterious etiologic factors are pulmonary hyperinflation for the respiratory muscles and deconditioning secondary to reduced physical activity for limb muscles. Nonetheless, cigarette smoke, systemic inflammation, nutritional abnormalities, exercise, exacerbations, anabolic insufficiency, drugs and comorbidities also seem to play a relevant role. All these factors modify the phenotype of the muscles, through the induction of several biological phenomena in patients with COPD. While respiratory muscles improve their aerobic phenotype (percentage of oxidative fibers, capillarization, mitochondrial density, enzyme activity in the aerobic pathways, etc.), limb muscles exhibit the opposite phenotype. In addition, both muscle groups show oxidative stress, signs of damage and epigenetic changes. However, fiber atrophy, increased number of inflammatory cells, altered regenerative capacity; signs of apoptosis and autophagy, and an imbalance between protein synthesis and breakdown are rather characteristic features of the limb muscles, mostly in patients with reduced body weight. Despite that significant progress has been achieved in the last decades, full elucidation of the specific roles of the target biological mechanisms involved in COPD muscle dysfunction is still required. Such an achievement will be crucial to adequately tackle with this relevant clinical problem of COPD patients in the near-future.

Association of C-reactive protein and interleukin-6 with new-onset fatigue in the Whitehall II prospective cohort study

BACKGROUND

Although basic research on neuroimmune interactions suggests that inflammatory processes may play a role in the development of fatigue, population-based evidence on this association is limited. This study examined whether plasma C-reactive protein (CRP) and interleukin-6 (IL-6), biomarkers of systemic inflammation, predict fatigue onset.

METHOD

The Whitehall II study is a large-scale cohort study conducted in 20 civil service departments in London. Plasma CRP and IL-6 were measured in 4847 non-fatigued participants at phase 3 (1991-1993, aged 39-63 years). Fatigue was assessed using the Vitality subscale of the 36-item Short Form Health Survey (SF-36) at phase 3 and phase 4 (1995-1996).

RESULTS

During a mean follow-up of 3.1 years, 957 new fatigue cases (19.7%) were identified using the pre-established cut-off score of ≤ 50 on the Vitality subscale. CRP values were dichotomized as low (<1.0 mg/l ) or high (≥ 1.0 mg/l) using the Centers for Disease Control/American Heart Association recommendations. Similarly, IL-6 values were also dichotomized as low (<1.5 pg/ml) or high (≥ 1.5 pg/ml). After full adjustment for sociodemographic and biobehavioral covariates, the odds ratios for new-onset fatigue were 1.28 [95% confidence interval (CI) 1.09-1.49, p = 0.003] for high CRP and 1.24 (95% CI 1.06-1.45, p = 0.008) for high IL-6. Similar results were found when CRP and IL-6 were treated as continuous variables.

CONCLUSIONS

Plasma CRP and IL-6 were prospectively associated with new-onset fatigue, supporting the hypothesis that low-grade inflammation has a role in the development of fatigue.

Pathophysiology of muscle dysfunction in COPD

Muscle dysfunction often occurs in patients with chronic obstructive pulmonary disease (COPD) and may involve both respiratory and locomotor (peripheral) muscles. The loss of strength and/or endurance in the former can lead to ventilatory insufficiency, whereas in the latter it limits exercise capacity and activities of daily life. Muscle dysfunction is the consequence of complex interactions between local and systemic factors, frequently coexisting in COPD patients. Pulmonary hyperinflation along with the increase in work of breathing that occur in COPD appear as the main contributing factors to respiratory muscle dysfunction. By contrast, deconditioning seems to play a key role in peripheral muscle dysfunction. However, additional systemic factors, including tobacco smoking, systemic inflammation, exercise, exacerbations, nutritional and gas exchange abnormalities, anabolic insufficiency, comorbidities and drugs, can also influence the function of both respiratory and peripheral muscles, by inducing modifications in their local microenvironment. Under all these circumstances, protein metabolism imbalance, oxidative stress, inflammatory events, as well as muscle injury may occur, determining the final structure and modulating the function of different muscle groups. Respiratory muscles show signs of injury as well as an increase in several elements involved in aerobic metabolism (proportion of type I fibers, capillary density, and aerobic enzyme activity) whereas limb muscles exhibit a loss of the same elements, injury, and a reduction in fiber size. In the present review we examine the current state of the art of the pathophysiology of muscle dysfunction in COPD.

Tobacco use or body mass--do they predict tuberculosis mortality in Mumbai, India? Results from a population-based cohort study

Tobacco use and under-nutrition are major public health concerns and tuberculosis is a major cause of morbidity and mortality in India. Using a cohort of 148,173 persons (recruited 1991-1997 and followed-up 1997-2003) the joint effects of tobacco use and BMI on tuberculosis mortality was studied. Tobacco use in any form and low-BMI had joint effect on tuberculosis mortality and the interaction effect was synergistic in men and antagonistic in women. Self-reported tuberculosis was associated with increased risk of tuberculosis mortality. In contrast, no such association was observed for self-reported diabetes persons. The risk pattern remained unchanged even after excluding tuberculosis deaths occurred within 1(st) two years of follow-up. This study highlights importance of age consideration of individual while excluding early deaths. Around 27% male tuberculosis deaths were attributable to their being underweight and smoker, while 22% male and 37% female deaths were attributable to their being underweight and smokeless tobacco user.

Behavioral factors related to fatigue among persons with spinal cord injury

OBJECTIVE

To examine behavioral risk factors in relation to fatigue after spinal cord injury (SCI), specifically cardiovascular-related behaviors, prescription medication use, and alcohol and cigarette use.

DESIGN

Cross-sectional.

SETTING

A medical university in the southeastern United States.

PARTICIPANTS

Adults (N=2245) at least 1 year post-SCI from a large specialty hospital in the Southeast responded to a mail-in survey.

INTERVENTION

Not applicable.

MAIN OUTCOMES MEASURE

The Modified Fatigue Impact Scale-5-item version was used to assess disabling fatigue.

RESULTS

Of participants, 8.3% had disabling fatigue, 45.3% reported fatigue rarely to never impacted their life, and 46.4% reported having some fatigue. Persons who reported having less exercise than others with a similar injury level were 2.49 times as likely to have disabling fatigue as persons who reported more exercise. Those with a fair or poor diet were also more likely to have disabling fatigue. Use of prescription medication to treat pain was associated with disabling fatigue, as was being CAGE positive. Among nonbehavioral variables, race and injury severity were significantly associated with disabling fatigue.

CONCLUSIONS

We identified several behavioral predictors of disabling fatigue, including cardiovascular risk factors, prescription medication use, and alcohol use. These factors are important because they are able to be modified and could be potential factors for prevention or intervention.

Sex differences in effects of cigarette smoking and 24-hr abstinence on plasma arginine vasopressin

The present study examined plasma arginine vasopressin (AVP) levels in 18 smokers (10 men, 8 women) and in 22 non-smokers (12 men, 10 women). Non-smokers came to the laboratory once, whereas smokers came twice: while smoking freely and following 24-hr abstinence. Plasma was collected for AVP assessment; salivary cotinine and expired carbon monoxide levels confirmed smoking status. Among non-smokers, men had higher AVP levels than did women (p<0.05). Among smokers, however, women displayed higher AVP levels than did men both while smoking and following abstinence (p's<0.05). Among men, smoking resulted in lower AVP levels compared to non-smoking men. In contrast, women who smoked displayed higher AVP levels compared to their non-smoking counterparts. AVP levels were not affected by 24-hr abstinence among smokers, regardless of sex, which suggests that dysregulation in AVP levels in tobacco smokers continues even following 24-hr abstinence. Findings are consistent with previous reports of elevated Th1/Th2 immune function among female smokers compared to male smokers and to male and female non-smokers. Data suggest sex-dependent AVP changes during smoking that could contribute to negative impact of smoking on cardiovascular health.

The associations of adiposity, physical activity and inflammation with fatigue in older adults

Persistent feelings of fatigue are a widespread complaint reported by older adults, and are associated with detriments in health and quality of life. The aim of this study was to determine the influence of weight status, habitual physical activity and inflammation, after controlling for common psychosocial variables such as depression, on perceptions of fatigue in relatively healthy older adults. Older men and women (N=182, age=69.2±6.7 years, 98 men) were assessed for adiposity via dual-energy X-ray absorptiometry, physical activity (PA) using accelerometers, systemic inflammation [serum C-reactive protein (CRP), interleukin-6 (IL-6), sIL-6R and WBC count], fatigue according to the Multidimensional Fatigue Inventory (MFI), sleep using the Pittsburgh Sleep Quality Index (PSQI) and depression via the Geriatric Depression Scale (GDS). Men and women reported similar levels of fatigue in all dimensions (p>0.05) except women reported higher levels of mental fatigue than men (p=0.049). With the exception of mental fatigue, adiposity was positively, and physical activity was inversely associated with all other dimension of fatigue (r range=0.20-0.42, and -0.18 to -0.37, respectively). CRP, IL-6 and WBC were also related to several dimensions of fatigue (r range=0.15-0.26). Regression analyses revealed that after controlling for other factors, including depression and sleep quality, adiposity independently explained a significant amount of the variance in general and physical fatigue. In addition to depression and sleep quality, adiposity may represent a potential target for reducing fatigue in older adults.

Guided imagery as a treatment option for fatigue: a literature review

PURPOSE

Fatigue is one of the most common complaints experienced among the general population. Because fatigue is recognized as a biobehavioral occurrence, a biobehavioral intervention such as guided imagery may be effective in reducing self-reported fatigue. Therefore, the purpose of this study was to explore the research literature related to the use of guided imagery as a nonpharmacological mind-body intervention for the symptom of fatigue.

METHOD

The electronic databases MEDLINE, CINAHL, PsychInfo, Psychology and Behavioral Sciences Collection and the Cochrane Library were searched from January 1980 to June 2010.

FINDINGS

Of 24 articles retrieved, eight met the inclusion criteria and were included in this systematic literature review. FINDINGS were inconsistent regarding the effectiveness of guided imagery on fatigue. Studies varied in study length, duration of the applied guided imagery intervention, dosage, and whether the images were targeted to the purpose of the intervention.

IMPLICATIONS

Guided imagery is a simple, economic intervention with the potential to effectively treat fatigue, thus further research is warranted using systematic, well-designed methodologies Standardizing guided imagery interventions according to total duration of exposure and targeted imagery in a variety of different populations adequately powered to detect changes will contribute to and strengthen nursing's symptom-management armamentarium.

Prospective association between C-reactive protein and fatigue in the coronary artery risk development in young adults study

BACKGROUND

Fatigue is highly prevalent and causes serious disruption in quality of life. Although the underlying biological mechanism is unknown, increases in inflammation have been implicated. This prospective study examined the association between C-reactive protein (CRP), a biomarker of systemic inflammation, and fatigue 5 years later.

METHODS

The Coronary Artery Risk Development in Young Adults (CARDIA) study is a population-based longitudinal study conducted in four U.S. cities. Highly sensitive CRP concentration and fatigue were measured in 2983 African American and white adults at both year 15 (2000-2001, ages 33-45 years) and year 20 (2005-2006) examinations. Fatigue was assessed using the vitality subscale of the 12-item Short Form Health Survey.

RESULTS

Plasma CRP concentration at baseline (i.e., CARDIA year 15) was a significant predictor of fatigue level 5 years later (unadjusted beta = .126, p < .001). After adjustment for potential confounders, this association remained significant (adjusted beta = .044, p = .033). Additionally, baseline CRP independently predicted fatigue in the subgroup of participants without medical comorbidity (adjusted beta = .051, p = .039). Fatigue was associated with a persistent elevation of CRP at both examinations but not with a transient elevation of CRP at only one of the examinations.

CONCLUSIONS

This is the first study to demonstrate a prospective association between an inflammatory marker and fatigue in a general population. Furthermore, the association between low-grade systemic inflammation and fatigue seems primarily driven by persistent immune activation and not explained by the presence or development of medical comorbidity.

Correlates and outcomes of fatigue among incident dialysis patients

BACKGROUND & OBJECTIVES

Fatigue is a debilitating symptom experienced by patients undergoing dialysis, but there is only limited information on its prevalence and its association with patient outcomes. This study examines the correlates of self-reported fatigue at initiation of dialysis and after 1 yr and assesses the extent to which fatigue was associated with health-related quality of life and survival.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A longitudinal cohort of 917 incident hemodialysis and peritoneal dialysis patients who completed the CHOICE Health Experience Questionnaire (CHEQ) participated in the study. Fatigue was assessed using the SF-36 vitality scale. Known predictors of fatigue including sociodemographic and psychosocial factors, dialysis-related factors, biochemical variables including inflammatory markers, comorbidities, and medications were used as covariates.

RESULTS

A low vitality score was independently associated with white race, higher Index of Coexistent Disease score, higher body mass index, lack of physical exercise, antidepressant use, and higher C-reactive protein levels (CRP). A lower vitality score was strongly associated with lower SF-36 physical functioning, mental health, bodily pain scores, and decreased sleep quality (all P < 0.001) at baseline. Among surviving participants, higher serum creatinine at baseline was associated with preserved vitality at 1 yr. Patients with the highest baseline vitality scores were associated with longer survival (hazard ratio 0.75; 95% CI 0.58 to 0.96, P = 0.03).

CONCLUSIONS

The findings of this study demonstrate that ESRD patients experience profound levels of fatigue and elucidate its correlates. Also, the association of fatigue with survival may have significant implications for this population.

Fatigue before and after mild traumatic brain injury: Pre–post-injury comparisons in relation toApolipoproteinE

PRIMARY OBJECTIVE

To assess the incidence of fatigue for persons following a mild traumatic brain injury (MTBI) and to evaluate the relationship between fatigue and APOE genotype. As fatigue is often found to be influenced by anxiety, depression and sleep disturbance, these factors were also measured.

METHODS AND PROCEDURES

Thirty-one persons who sustained a MTBI were drawn from a population-based longitudinal study. Each person who sustained a MTBI was matched by age, gender, education and APOE genotype with two non-head injury controls. Self-reported pre- and post-injury incidence of fatigue, anxiety, depression and sleep disturbance was compared within-group and between groups.

RESULTS

For the MTBI group, incidence of fatigue was almost twice as common post- than pre-injury, whereas there was no corresponding change in a non-injured control group. Within the MTBI-group, post-injury fatigue was particularly common for carriers of the APOE epsilon4 allele.

CONCLUSIONS

Fatigue is common sequela after a MTBI and especially pronounced for carriers of the APOE epsilon4 allele.

Mitochondrial DNA adducts in the lung and liver of F344 rats chronically treated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and (S)-4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol

Two recent studies conducted in our laboratory have demonstrated formation and accumulation of pyridyloxobutyl (POB) and pyridylhydroxybutyl (PHB) adducts in lung and liver total DNA of F344 rats chronically treated with the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and (R)- and (S)-enantiomers of its metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). In this study, we measured POB and PHB adducts in lung and liver mitochondrial DNA (mtDNA), as previous studies suggest a potentially important role of mtDNA in carcinogenesis. Rats were sacrificed after 1, 2, 5, 10, 16, and 20 weeks of treatment with 10 ppm of NNK or (S)-NNAL in drinking water, and mtDNA and nuclear DNA (nDNA) adduct levels in the lung and liver were determined by LC-ESI-MS/MS-SRM. The mean levels of individual POB adducts in mtDNA at all time points were slightly higher than those in nDNA for both NNK and (S)-NNAL-treated rats in the lung (P < 0.001 for both treatments) but not in the liver (P > 0.05). Lung mtDNA of both NNK- and (S)-NNAL-treated rats contained higher concentrations of the sum of three POB adducts (P < 0.001 for both treatments) than nDNA, while the levels of mtDNA and nDNA total POB adducts in the liver were not significantly different in either NNK- or (S)-NNAL-treated rats. Analysis of PHB adducts in mtDNA and nDNA produced results similar to those obtained for POB adducts. The steady accumulation of the lung and liver mtDNA adducts over the course of the study indicates inefficient repair of these adducts in mtDNA. This is the first study to examine the formation of NNK- and (S)-NNAL-derived adducts in rat mtDNA. The results support the hypothesis that preferential binding of tobacco carcinogens to mtDNA of the lung might be functionally important in the development of smoking-induced lung cancer.

Abnormal liver function and central obesity associate with work-related fatigue among the Taiwanese workers

AIM: To examine the associations between objective health indicators and high need for recovery (NFR) after work, one of the subjective presentations of work related-fatigue, among apparently healthy workers in modern workplaces.

METHODS: From October to December, 2007, an annual health examination was performed for the workers from an electronics manufacturing factory in Taiwan. Health records of 1216 workers with a relatively homogeneous socioeconomic status were used for analysis. The health checkups included personal and NFR scale questionnaires, physical examinations, blood tests for biochemistry and hematology. The workers within the top tertile NFR score were defined as high-NFR workers.

RESULTS: After adjusted for potential confounders, the workers with elevated alanine aminotransferase (ALT) and central obesity had a significantly higher NFR after work, with increased risks of 1.4-fold [95% confidence interval (CI) = 1.01-2.0] and 1.8-fold (95% CI = 1.2-2.7), respectively. Shiftworkers had a 2.0-fold (95% CI = 1.5-2.6) increased risk for high-NFR. The associations between high-NFR and lipid profiles, blood sugar, hematology indexes or blood pressure were insignificant after controlling for confounders.

CONCLUSION: For apparently healthy workers, high NFR after work is not simply a subjective experience. Objective health measures, such as elevated ALT and increased waist circumference, should be carefully evaluated for the apparently healthy workers having a higher NFR after work.

Skeletal muscle properties and fatigue resistance in relation to smoking history

Although smoking-related diseases, such as chronic obstructive pulmonary disease (COPD), are often accompanied by increased peripheral muscle fatigability, the extent to which this is a feature of the disease or a direct effect of smoking per se is not known. Skeletal muscle function was investigated in terms of maximal voluntary isometric torque, activation, contractile properties and fatigability, using electrically evoked contractions of the quadriceps muscle of 40 smokers [19 men and 21 women; mean (SD) cigarette pack years: 9.9 (10.7)] and age- and physical activity level matched non-smokers (22 men and 23 women). Maximal strength and isometric contractile speed did not differ significantly between smokers and non-smokers. Muscle fatigue (measured as torque decline during a series of repetitive contractions) was greater in smokers (P = 0.014), but did not correlate with cigarette pack years (r = 0.094, P = 0.615), cigarettes smoked per day (r = 10.092, P = 0.628), respiratory function (%FEV_1pred) (r = −0.187, P = 0.416), or physical activity level (r = −0.029, P = 0.877). While muscle mass and contractile properties are similar in smokers and non-smokers, smokers do suffer from greater peripheral muscle fatigue. The observation that the cigarette smoking history did not correlate with fatigability suggests that the effect is either acute and/or reaches a ceiling, rather than being cumulative. An acute and reversible effect of smoking could be caused by carbon monoxide and/or other substances in smoke hampering oxygen delivery and mitochondrial function.

Disruption in Th1/Th2 immune response in young adult smokers

Interferon (IFN)-gamma and IL-10 cytokines, measures of Th1 and Th2 immunity, were examined in 20 healthy nonsmokers (12 males, 8 females) and 19 smokers (11 males, 8 females), aged 19-41 years (23.46+/-0.82 years). Nonsmokers came to the laboratory once; smokers came to the laboratory after ad lib smoking and following 24-h smoking abstinence. Salivary cotinine and expired CO confirmed smoking status. Plasma was collected at the end of each lab session and assayed for peripheral IFN-gamma and IL-10 levels. Among smokers, peripheral IFN-gamma, IL-10, or IFN-gamma/IL-10 ratio levels did not change in response to 24-h smoking abstinence. IFN-gamma levels and IFN-gamma/IL-10 ratios were higher among female smokers while smoking and following 24-h abstinence compared to male smokers in both conditions and compared to male and female nonsmokers. There was no sex or smoking status difference in IL-10 levels. Results suggest that cigarette smoking may have at least short-term damaging effects on the body's normal immune balance, particularly for women.

Association between tobacco use and body mass index in urban Indian population: implications for public health in India

BACKGROUND

Body mass index [BMI, weight (kg)/height (m2)], a measure of relative weight, is a good overall indicator of nutritional status and predictor of overall health. As in many developing countries, the high prevalence of very low BMIs in India represents an important public health risk. Tobacco, smoked in the form of cigarettes or bidis (handmade by rolling a dried rectangular piece of temburni leaf with 0.15-0.25 g of tobacco) or chewed, is another important determinant of health. Tobacco use also may exert a strong influence on BMI.

METHODS

The relationship between very low BMI (< 18.5 kg/m2) and tobacco use was examined using data from a representative cross-sectional survey of 99,598 adults (40,071 men and 59,527 women) carried out in the city of Mumbai (formerly known as Bombay) in western India. Participants were men and women aged > or = 35 years who were residents of the main city of Mumbai.

RESULTS

All forms of tobacco use were associated with low BMI. The prevalence of low BMI was highest in bidi-smokers (32% compared to 13% in non-users). For smokers, the adjusted odds ratio (OR) and 95% confidence interval (CI) were OR = 1.80(1.65 to 1.96) for men and OR = 1.59(1.09 to 2.32) for women, respectively, relative to non-users. For smokeless tobacco and mixed habits (smoking and smokeless tobacco), OR = 1.28(1.19 to 1.38) and OR = 1.83(1.67 to 2.00) for men and OR = 1.50(1.43 to 1.59) and OR = 2.19(1.90 to 3.41) for women, respectively.

CONCLUSION

Tobacco use appears to be an independent risk factor for low BMI in this population. We conclude that in such populations tobacco control research and interventions will need to be conducted in concert with nutrition research and interventions in order to improve the overall health status of the population.

Risk indicators of metabolic syndrome in young adults: A preliminary investigation on the influence of tobacco smoke exposure and gender

BACKGROUND

Metabolic syndrome is characterized by hypertension, dyslipidemia, insulin resistance, and obesity. Limited investigations have studied early indicators of metabolic syndrome in healthy young adults before diagnosis of disease.

PURPOSE

The purpose of this investigation is to identify shifts in cardiovascular (CV), metabolic, and immune variables consistent with metabolic syndrome but occurring before development of the disorder, and to determine whether these variables are influenced by gender or cigarette smoking.

METHODS

A pilot study of 41 subjects ages 18 to 39 years, with 20 smokers and 21 nonsmokers, was undertaken. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured to evaluate CV status; cholesterol, body mass index, leptin, percent glycated albumin, and homocysteine were measured to evaluate metabolic status; C-reactive protein, interleukin-1beta, and interleukin-10 were measured to evaluate immunologic status. Risk scores were assigned to each indicator, and total risk score was computed.

RESULTS

Men had higher SBP (P<.001), DBP (P=.046), and body mass index (P=.01), whereas women had higher leptin (P=.002). Total risk scores in men were greater (P=.02). There was no effect of smoking on risk score, related to the increase in two risks for smokers (SBP, P=.04, DBP; P=.027) reciprocated by a decrease in another (percentage of glycated albumin; P=.02).

CONCLUSION

Risk factors contributing to metabolic syndrome are present and highest in young men compared with women, whereas the effects of cigarette smoking on the syndrome are mixed. Early intervention to reduce modifiable risks may prevent full expression of disease.

Fatigue and physical activity in older women after myocardial infarction

BACKGROUND

Within 6 years of a myocardial infarction (MI) more women (35%) than men (18%) will have another MI. Participation in physical activity is one of the most effective methods to reduce cardiac risks; however, few older women participate. One of the most frequently reported barriers to physical activity is fatigue.

OBJECTIVES

The specific aims of this study were to (1) describe factors related to fatigue in older women after MI and (2) examine the relationship of fatigue to physical activity in older women after MI.

METHODS

This descriptive correlational study examined the effects of age, body mass index, comorbidities, sleep, beta-blocker medication, depression, and social support on fatigue and physical activity in women (N = 84), ages 65 to 88 years old, 6 to 12 months post-MI. All women had their height and weight measured and completed (1) a health form on comorbidities, physical activity, and medication history; (2) the Geriatric Depression Scale; (3) the Epworth Sleepiness Scale; (4) the Revised Piper Fatigue Scale; and (5) the Social Provisions Scale.

RESULTS

The majority (67%) of the women reported fatigue that they perceived as different from fatigue before their MI. Moderately strong correlations were noted among depression, sleep, and fatigue, and multivariate analysis indicated that depression and sleep significantly accounted for 32.7% of the variance in fatigue. Although only 61% of the women reported participating in physical activity for exercise, most were meeting minimal kilocalories per week for secondary prevention. Fatigue was not significantly associated with participation in physical activity.

CONCLUSION

Describing correlates to fatigue and older women's participation in physical activity after MI are important to develop interventions targeted at increasing women's participation in physical activity, thus decreasing their risk for recurrent MIs.

Leptin, hunger, and body weight: Influence of gender, tobacco smoking, and smoking abstinence

Leptin is a hormone involved in body weight and hunger regulation, and may contribute to the inverse relationship between cigarette smoking and body weight. Leptin levels, body mass indices (BMIs), and hunger ratings were determined in 22 nonsmokers (12 male, 10 female) and 19 cigarette smokers (11 male, 8 female). Smokers were tested after ad lib smoking and following a 24-h smoking abstinence period; nonsmokers came to the laboratory once. Leptin levels were not different among the groups. Hunger ratings, however, were higher after smoking abstinence compared to after ad lib smoking and nonsmokers (Ps<.05); levels of hunger did not differ between ad lib smokers and nonsmokers. Men reported higher hunger levels than did women, but women had higher serum leptin levels than did men, regardless of smoking condition (P<.05). Leptin levels were correlated with BMI (P<.05) among smokers only. This first study on leptin responses in female smokers suggests that leptin levels do not change following a 24-h smoking abstinence period and that leptin may not contribute to increased hunger following smoking abstinence.

C-reactive protein and depressed mood in a sub-group of smokers during nicotine abstinence

Cigarette smokers frequently fail multiple attempts to quit smoking, often because of the unpleasant symptoms that accompany quitting. Similar unpleasant symptoms accompany inflammatory responses during infection and autoimmune disease. The hypothesis that smoking abstinence induces inflammation was tested. Eighteen smokers (n = 18) were evaluated while smoking freely and after 24 h of nicotine abstinence. Immune, cardiovascular and psychological measures were collected. Hunger, nervousness, anxiety, restlessness and irritability increased during abstinence (p < 0.05); systolic blood pressure and heart rate levels decreased (p < 0.05). Analysis demonstrated a split among smokers in response to abstinence compared with smoking freely; some smokers (n = 10) displayed increased C-reactive protein (CRP, p < 0.05) whereas others (n = 8) responded with decreased CRP (p < 0.05). An increase in symptoms of depressed mood and a fall in heart rate occurred only in those who displayed increased CRP with nicotine abstinence ( p < 0.05), while systolic blood pressure fell only in those whose CRP levels decreased with abstinence ( p < 0.05). Interleukin-1 and interleukin-6 did not change with abstinence. The results suggest that 24 h nicotine abstinence does not stimulate inflammation among all smokers, but that a sub-group of smokers do demonstrate an inflammatory response with significant negative psychological and physiological symptomatology.