Machine Learning-Driven Phenogrouping and Cardiorespiratory Fitness Response in Metastatic Breast Cancer.

PURPOSE: The magnitude of cardiorespiratory fitness (CRF) impairment during anticancer treatment and CRF response to aerobic exercise training (AT) are highly variable. The aim of this ancillary analysis was to leverage machine learning approaches to identify patients at high risk of impaired CRF and poor CRF response to AT. METHODS: We evaluated heterogeneity in CRF among 64 women with metastatic breast cancer randomly assigned to 12 weeks of highly structured AT (n = 33) or control (n = 31). Unsupervised hierarchical cluster analyses were used to identify representative variables from multidimensional prerandomization (baseline) data, and to categorize patients into mutually exclusive subgroups (ie, phenogroups). Logistic and linear regression evaluated the association between phenogroups and impaired CRF (ie, ≤16 mL O2·kg-1·min-1) and CRF response. RESULTS: Baseline CRF ranged from 10.2 to 38.8 mL O2·kg-1·min-1; CRF response ranged from -15.7 to 4.1 mL O2·kg-1·min-1. Of the n = 120 candidate baseline variables, n = 32 representative variables were identified. Patients were categorized into two phenogroups. Compared with phenogroup 1 (n = 27), phenogroup 2 (n = 37) contained a higher number of patients with none or >three lines of previous anticancer therapy for metastatic disease and had lower resting left ventricular systolic and diastolic function, cardiac output reserve, hematocrit, lymphocyte count, patient-reported outcomes, and CRF (P < .05) at baseline. Among patients allocated to AT (phenogroup 1, n = 12; 44%; phenogroup 2, n = 21; 57%), CRF response (-1.94 ± 3.80 mL O2·kg-1·min-1 v 0.70 ± 2.22 mL O2·kg-1·min-1) was blunted in phenogroup 2 compared with phenogroup 1. CONCLUSION: Phenotypic clustering identified two subgroups with unique baseline characteristics and CRF outcomes. The identification of CRF phenogroups could help improve cardiovascular risk stratification and guide investigation of targeted exercise interventions among patients with cancer.

Correction: Effects of Aerobic Exercise on Cardiorespiratory Fitness, Cardiovascular Risk Factors, and Patient-Reported Outcomes in Long-Term Breast Cancer Survivors: Protocol for a Randomized Controlled Trial.

[This corrects the article DOI: 10.2196/45244.].

Systolic myocardial function measured by echocardiographic speckle-tracking and peak oxygen consumption in pediatric childhood cancer survivors-a PACCS study.

Background: Cancer therapy-related cardiotoxicity is a major cause of cardiovascular morbidity in childhood cancer survivors. The aims of this study were to investigate systolic myocardial function and its association to cardiorespiratory fitness in pediatric childhood cancer survivors. Methods: In this sub-study of the international study "Physical Activity and fitness in Childhood Cancer Survivors" (PACCS), echocardiographic measures of left ventricular global longitudinal strain (LV-GLS) and right ventricular longitudinal strain (RV-LS) were measured in 128 childhood cancer survivors aged 9-18 years and in 23 age- and sex-matched controls. Cardiorespiratory fitness was measured as peak oxygen consumption achieved on treadmill and correlated to myocardial function. Results: Mean LV-GLS was reduced in the childhood cancer survivors compared to the controls, -19.7% [95% confidence interval (CI) -20.1% to -19.3%] vs. -21.3% (95% CI: -22.2% to -20.3%) (p = 0.004), however, mainly within normal range. Only 13% of the childhood cancer survivors had reduced LV longitudinal strain z-score. Mean RV-LS was similar in the childhood cancer survivors and the controls, -23.2% (95% CI: -23.7% to -22.6%) vs. -23.3% (95% CI: -24.6% to -22.0%) (p = 0.8). In the childhood cancer survivors, lower myocardial function was associated with lower peak oxygen consumption [correlation coefficient (r) = -0.3 for LV-GLS]. Higher doses of anthracyclines (r = 0.5 for LV-GLS and 0.2 for RV-LS) and increasing time after treatment (r = 0.3 for LV-GLS and 0.2 for RV-LS) were associated with lower myocardial function. Conclusions: Left ventricular function, but not right ventricular function, was reduced in pediatric childhood cancer survivors compared to controls, and a lower left ventricular myocardial function was associated with lower peak oxygen consumption. Furthermore, higher anthracycline doses and increasing time after treatment were associated with lower myocardial function, implying that long-term follow-up is important in this population at risk.

Effects of Aerobic Exercise on Cardiorespiratory Fitness, Cardiovascular Risk Factors, and Patient-Reported Outcomes in Long-Term Breast Cancer Survivors: Protocol for a Randomized Controlled Trial.

BACKGROUND: Anthracycline-based chemotherapy has been mainstay of adjuvant breast cancer therapy for decades. Although effective, anthracyclines place long-term breast cancer survivors at risk of late effects, such as reduced cardiorespiratory fitness and increased risk of cardiovascular disease. Previous research has shown beneficial effects of exercise training on cardiorespiratory fitness, but the effects of exercise on limiting factors for cardiorespiratory fitness, cardiovascular risk factors, and patient-reported outcomes in long-term survivors are less clear. Whether previous exposure to breast cancer therapy modulates the effects of exercise is also unknown. OBJECTIVE: The primary aim of the CAUSE (Cardiovascular Survivors Exercise) trial is to examine the effect of aerobic exercise on cardiorespiratory fitness in anthracycline-treated long-term breast cancer survivors. Secondary aims are to examine effects of exercise training on limiting factors for cardiorespiratory fitness, cardiovascular risk factors, and patient-reported outcomes, and to compare baseline values and effects of exercise training between similar-aged women with and those without prior breast cancer. A third aim is to examine the 24-month postintervention effects of aerobic exercise on primary and secondary outcomes. METHODS: The CAUSE trial is a 2-armed randomized controlled trial, where 140 long-term breast cancer survivors, 8-12 years post diagnosis, are assigned to a 5-month nonlinear aerobic exercise program with 3 weekly sessions or to standard care. Seventy similar-aged women with no history of cancer will undergo the same exercise program. Cardiorespiratory fitness measured as peak oxygen consumption (VO2peak), limiting factors for VO2peak (eg, cardiac function, pulmonary function, hemoglobin mass, blood volume, and skeletal muscle characteristics), cardiovascular risk factors (eg, hypertension, diabetes, dyslipidemia, obesity, physical activity level, and smoking status), and patient-reported outcomes (eg, body image, fatigue, mental health, and health-related quality of life) will be assessed at baseline, post intervention, and 24 months post intervention. RESULTS: A total of 209 patients were included from October 2020 to August 2022, and postintervention assessments were completed in January 2023. The 24-month follow-up will be completed in February 2025. CONCLUSIONS: The findings from the CAUSE trial will provide novel scientific understanding of the potential benefits of exercise training in long-term breast cancer survivors. TRIAL REGISTRATION: ClinicalTrials.gov NCT04307407; https://clinicaltrials.gov/ct2/show/NCT04307407. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/45244.

Polyneuropathy in Adolescent Childhood Cancer Survivors: The PACCS Study.

BACKGROUND: Childhood cancer survivors (CCS) are at risk of polyneuropathy due to chemotherapy, but studies in young survivors are scarce and diagnosis is challenging. We aimed to study the presence of polyneuropathy and the possible effect of cumulative doses of chemotherapeutic agents in a representative group of adolescent survivors. METHODS: CCS aged nine to 18 years and age- and sex-matched controls were recruited from the cross-sectional Physical Activity and Fitness among Childhood Cancer Survivors (PACCS) study. CCS with various cancer diagnoses who had ended cancer treatment one year or more before study were included. Polyneuropathy was evaluated clinically and with nerve conduction studies (NCSs) in three motor and five sensory nerves. We used mixed-effects linear regression models to compare CCS and controls, and investigate possible associations between cumulative chemotherapy doses and NCS amplitudes. RESULTS: A total of 127 CCS and 87 controls were included, with 14% CCS having probable or confirmed polyneuropathy. NCS amplitudes were lower in survivors compared with controls in all nerves. The largest mean difference was 3.47 µV (95% confidence interval [CI], 2.18 to 4.75) in the tibial plantar medial sensory and 1.91 mV (95% CI, 0.78 to 3.04) in the tibial motor nerve. The cumulative dose of platinum derivatives was associated with lower tibial motor nerve amplitude (-0.20; 95% CI, -0.35 to -0.04 mV for 100 mg/m2 dose increase) but not in other nerves. We found no significant associations between vinca alkaloids cumulative dose and amplitudes. CONCLUSIONS: CCS without clinical signs or symptoms of polyneuropathy may have subtle nerve affection. The clinical long-term impact of this novel observation should be evaluated in larger, longitudinal studies.

Validity of Estimated Cardiorespiratory Fitness in Patients With Primary Breast Cancer.

Background: Estimated peak oxygen consumption (Vo2peak) is widely used in oncology; however, estimated Vo2peak equations were developed in noncancer settings. Objectives: The aim of this study was to evaluate the validity of estimated Vo2peak in women with primary breast cancer and to develop oncology-specific estimated Vo2peak equations. Methods: Vo2peak was directly measured (TrueOne 2400, Parvo Medics) during 380 cardiopulmonary exercise tests in women previously treated for breast cancer (mean age: 59 ± 10 years; 3.1 ± 1.2 years post-therapy). The American College of Sports Medicine (ACSM), the Fitness Registry and the Importance of Exercise National Database (FRIEND), and heart failure (HF)-FRIEND equations were used to estimate Vo2peak. New equations were developed using patient and peak (Oncpeak) or submaximal (Oncsub) exercise test characteristics. Results: The median differences between measured and estimated Vo2peak were 7.0 mL O2·kg-1·min-1, 3.9 mL O2·kg-1·min-1, and -0.2 mL O2·kg-1·min-1 for ACSM, FRIEND, and HF-FRIEND, respectively. The number of estimated Vo2peak values within ±3.5 mL O2·kg-1·min-1 of the measured values was 70 (18%), 164 (43%), and 306 (81%) for ACSM, FRIEND, and HF-FRIEND, respectively. The Oncpeak and OncSub models included body mass index, age, a history of chemotherapy or radiation, the peak measured heart rate, and the treadmill grade and/or speed. The median differences between measured and estimated Vo2peak were 0.02 mL O2·kg-1·min-1 (Oncpeak) and -0.2 mL O2·kg-1·min-1 (Oncsub). Eighty-six percent (n = 325) and 76% (n = 283) estimated Vo2peak values were within ±3.5 mL O2·kg-1·min-1 of the measured Vo2peak values for Oncpeak and Oncsub, respectively. Conclusions: HF-FRIEND or oncology-specific equations could be applied to estimate Vo2peak in patients previously treated for breast cancer in settings where cardiopulmonary exercise tests are not available. (Trial Comparing the Effects of Linear Versus Nonlinear Aerobic Training in Women With Operable Breast Cancer [EXCITE]; NCT01186367.

The Physical Activity and Fitness in Childhood Cancer Survivors (PACCS) Study: Protocol for an International Mixed Methods Study.

BACKGROUND: Survivors of childhood cancer represent a growing population with a long life expectancy but high risks of treatment-induced morbidity and premature mortality. Regular physical activity (PA) may improve their long-term health; however, high-quality empirical knowledge is sparse. OBJECTIVE: The Physical Activity and Fitness in Childhood Cancer Survivors (PACCS) study comprises 4 work packages (WPs) aiming for the objective determination of PA and self-reported health behavior, fatigue, and quality of life (WP 1); physical fitness determination (WP 2); the evaluation of barriers to and facilitators of PA (WP 1 and 3); and the feasibility testing of an intervention to increase PA and physical fitness (WP 4). METHODS: The PACCS study will use a mixed methods design, combining patient-reported outcome measures and objective clinical and physiological assessments with qualitative data gathering methods. A total of 500 survivors of childhood cancer aged 9 to 18 years with ≥1 year after treatment completion will be recruited in follow-up care clinics in Norway, Denmark, Finland, Germany, and Switzerland. All participants will participate in WP 1, of which approximately 150, 40, and 30 will be recruited to WP 2, WP3, and WP 4, respectively. The reference material for WP 1 is available from existing studies, whereas WP 2 will recruit healthy controls. PA levels will be measured using ActiGraph accelerometers and self-reports. Validated questionnaires will be used to assess health behaviors, fatigue, and quality of life. Physical fitness will be measured by a cardiopulmonary exercise test, isometric muscle strength tests, and muscle power and endurance tests. Limiting factors will be identified via neurological, pulmonary, and cardiac evaluations and the assessment of body composition and muscle size. Semistructured, qualitative interviews, analyzed using systematic text condensation, will identify the perceived barriers to and facilitators of PA for survivors of childhood cancer. In WP 4, we will evaluate the feasibility of a 6-month personalized PA intervention with the involvement of local structures. RESULTS: Ethical approvals have been secured at all participating sites (Norwegian Regional Committee for Medical Research Ethics [2016/953 and 2018/739]; the Oslo University Hospital Data Protection Officer; equivalent institutions in Finland, Denmark [file H-19032270], Germany, and Switzerland [Ethics Committee of Northwestern and Central Switzerland, project ID: 2019-00410]). Data collection for WP 1 to 3 is complete. This will be completed by July 2022 for WP 4. Several publications are already in preparation, and 2 have been published. CONCLUSIONS: The PACCS study will generate high-quality knowledge that will contribute to the development of an evidence-based PA intervention for young survivors of childhood cancer to improve their long-term care and health. We will identify physiological, psychological, and social barriers to PA that can be targeted in interventions with immediate benefits for young survivors of childhood cancer in need of rehabilitation. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/35838.

Effects and tolerability of exercise therapy modality on cardiorespiratory fitness in lung cancer: a randomized controlled trial.

BACKGROUND: Poor cardiorespiratory fitness (CRF) is a cardinal feature of post-treatment primary lung cancer. The most effective exercise therapy regimen to improve CRF has not been determined. METHODS: In this parallel-group factorial randomized controlled trial, lung cancer survivors with poor CRF (below age-sex sedentary values) were randomly allocated to receive 48 consecutive supervised sessions thrice weekly of (i) aerobic training (AT)-cycle ergometry at 55% to >95% of peak oxygen consumption (VO2 peak); (ii) resistance training (RT)-lower and upper extremity exercises at 50-85% of maximal strength; (iii) combination training (CT)-AT plus RT; or (iv) stretching attention control (AC) for 16 weeks. The primary endpoint was change in CRF (VO2 peak, mL O2 ·kg-1 ·min-1 ). Secondary endpoints were body composition, muscle strength, patient-reported outcomes, tolerability (relative dose intensity of exercise), and safety. Analysis of covariance determined change in primary and secondary endpoints from baseline to post-intervention (Week 17) with adjustment for baseline values of the endpoint and other relevant clinical covariates. RESULTS: Ninety patients (65 ± 9 years; 66% female) were randomized (AT, n = 24; RT, n = 23; CT, n = 20; and AC, n = 23) of the planned n = 160. No serious adverse events were observed. For the overall cohort, the lost-to-follow-up rate was 10%. Mean attendance was ≥75% in all groups. In intention-to-treat analysis, VO2 peak increased 1.1 mL O2 ·kg-1 ·min-1 [95% confidence interval (CI): 0.0, 2.2, P = 0.04] and 1.4 mL O2 ·kg-1 ·min-1 (95% CI: 0.2, 2.5, P = 0.02) in AT and CT, respectively, compared with AC. There was no difference in VO2 peak change between RT and AC (-0.1 mL O2 ·kg-1 ·min-1 , 95% CI: -1.2, 1.0, P = 0.88). Favourable improvements in maximal strength and body composition were observed in RT and CT groups compared with AT and AC groups (Ps < 0.05). No between-group changes were observed for any patient-reported outcomes. Relative dose intensity of exercise was lower in RT and CT compared with AT (Ps < 0.05). CONCLUSIONS: In the context of a smaller than planned sample size, AT and CT significantly improved VO2 peak in lung cancer survivors; however, the tolerability-to-benefit ratio was superior for AT and hence may be the preferred modality to target impaired CRF in post-treatment lung cancer survivors.

Effect of high-intensity training on bone health and body composition in lung transplant recipients: A secondary analysis of a randomized controlled trial.

BACKGROUND: Loss of bone mineral and skeletal muscle mass is common after lung transplantation (LTx), and physical activity (PA) may prevent further deterioration. We aimed to assess the effects of 20-week high-intensity training (HIT) on body composition, bone health, and PA in LTx recipients, 6-60 months after surgery. METHODS: In a randomized controlled trial, 51 LTx recipients underwent Dual-energy X-ray absorptiometry (DXA), and PA level and sedentary time were objectively recorded by accelerometers for seven consecutive days. Of these, 39 participants completed the study, including 19 participants in the HIT group and 20 participants in the standard care group. RESULTS: Following the intervention, ANCOVA models revealed a nonsignificant between-group difference for change in lean body mass (LBM) and bone mineral density (BMD) of the lumbar spine of 0.4% (95% CI = -3.2, 1.5) (p = .464) and 1.0% (95% CI=-1.3, 3.4) (p = .373), respectively. Trabecular bone score (TBS) of the lumbar spine (L1-L4), however, increased by 2.2 ± 5.0% in the exercise group and decreased by -1.6 ± 5.9% in the control group, giving a between-group difference of 3.8% (95% CI=0.1, 7.5) (p = .043). There were no between-group differences in PA or sedentary time. CONCLUSION: High-intensity training after LTx improved TBS significantly, but not PA, LBM or BMD.

Determinants of cardiorespiratory fitness in very long-term survivors of allogeneic hematopoietic stem cell transplantation: a national cohort study.

PURPOSE: Survivors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) are at risk for cardiopulmonary adverse events. Data on long-term effects on cardiorespiratory fitness are limited. To address the gap in knowledge, we aimed to determine peak oxygen uptake (V̇O2peak) and identify associations between cardiorespiratory fitness and clinical characteristics, self-reported physical activity, cardiac, and pulmonary function. METHODS: In a nationwide, single-center cross-sectional study, 90 survivors [aged median (range) 35 (17-54) years, 56% females] were examined, 17 (6-26) years after allo-HSCT. Myeloablative conditioning comprised busulfan/cyclophosphamide or cyclophosphamide only. Methods included pulmonary function tests, echocardiography, and cardiopulmonary exercise test. RESULTS: Chronic graft-versus-host disease (cGVHD) was found in 31% of the subjects, of whom 40% had bronchiolitis obliterans syndrome (BOS). Seventy-one percent of the survivors did not meet WHO recommendations for physical activity and 42% were overweight. Reduced gas diffusion (DLCO) and systolic ventricular dysfunction (LVEF) were found in 44% and 31%, respectively. For the group, mean (95% CI), V̇O2peak was 36.4 (34.7-38.0) mL/min/kg [89 (85-93)% of predicted]. V̇O2peak was low at 43%. Cardiopulmonary factors and deconditioning were equally common limitations for exercise. In a multiple linear regression model, low V̇O2peak was associated with low DLCO, low LVEF, BOS, overweight, and inactivity. CONCLUSION: Half of the survivors had reduced cardiorespiratory fitness median 17 years after allo-HSCT. Cardiopulmonary factors and deconditioning were equally common limitations to exercise. We encourage long-term cardiopulmonary monitoring of allo-HSCT survivors and targeted advice on modifiable lifestyle factors.

Cardiorespiratory fitness on a treadmill in an adult cystic fibrosis population.

OBJECTIVES: (1) To describe the cardiorespiratory fitness (CRF) in an adult cystic fibrosis population related to sex and age, (2) to evaluate the cause of low CRF and (3) to study the association between peak oxygen uptake (VO2peak) and forced expiratory volume in 1 s (FEV1). METHODS: A total of 204 cardiopulmonary treadmill exercise tests (CPETs) performed by 116 patients were included. VO2peak, gas exchange, heart rate, oxygen saturation and ventilatory variables were measured.A low CRF was defined as a VO2peak <80% of predicted, ventilatory limitation was defined as a breathing reserve <15%, exercise hypoxaemia was defined as an oxygen saturation <88% and ventilation-perfusion mismatch was defined as a minute ventilation/ventilatory equivalent for carbon dioxide slope ≥34. In patients who had performed three or more CPETs, the annual change in FEV1 and VO2peak were calculated using linear regression. RESULTS: The VO2peak was 40.6±11.5 and 35.2±8.9 mL kg-1 min-1, which was 87±23 and 93±20 in percentage of predicted for men and women, respectively. VO2peak was moderately affected by age, for men (r=-0.36, p<0.001) and women (r=-0.53, p<0.001), respectively. In 45 of 101 tests where CRF was low, no cardiorespiratory limiting factors were identified. The correlation coefficient between VO2peak and FEV1 was r=0.64 (p<0.001). In participants with a low CRF, FEV1 ranged from 20% to 112% of predicted. CONCLUSIONS: The correlation between VO2peak and FEV1 was moderate. The majority of the tests resulted in a VO2peak within normal limits. Interestingly, 44% of the tests with a low VO2peak could be explained by deconditioning. Thus, exercise therapy may be beneficial for these patients.

Thromboembolic events after high-intensity training during cisplatin-based chemotherapy for testicular cancer: Case reports and review of the literature.

The randomized "Testicular cancer and Aerobic and Strength Training trial" (TAST-trial) aimed to evaluate the effect of high-intensity interval training (HIIT) on cardiorespiratory fitness during cisplatin-based chemotherapy (CBCT) for testicular cancer (TC). Here, we report on an unexpected high number of thromboembolic (TE) events among patients randomized to the intervention arm, and on a review of the literature on TE events in TC patients undergoing CBCT. Patients aged 18 to 60 years with a diagnosis of metastatic germ cell TC, planned for 3 to 4 CBCT cycles, were randomized to a 9 to 12 weeks exercise intervention, or to a single lifestyle counseling session. The exercise intervention included two weekly HIIT sessions, each with 2 to 4 intervals of 2 to 4 minutes at 85% to 95% of peak heart rate. The study was prematurely discontinued after inclusion of 19 of the planned 94 patients, with nine patients randomized to the intervention arm and 10 to the control arm. Three patients in the intervention arm developed TE complications; two with pulmonary embolism and one with myocardial infarction. All three patients had clinical stage IIA TC. No TE complications were observed among patients in the control arm. Our observations indicate that high-intensity aerobic training during CBCT might increase the risk of TE events in TC patients, leading to premature closure of the TAST-trial.

Cardiorespiratory Fitness and Physical Activity following Lung Transplantation: A National Cohort Study.

BACKGROUND: Low cardiorespiratory fitness and inactivity are common after lung transplantation (LTx). The causes of exercise intolerance are incompletely understood. OBJECTIVES: The aim of this study was to objectively assess cardiorespiratory fitness and physical activity, evaluate causes of exercise intolerance, and explore clinical factors associated with cardiorespiratory fitness after bilateral LTx (BLTx). MATERIALS AND METHODS: Peak oxygen uptake (V∙O2peak) and exercise-limiting factors were evaluated by a treadmill cardiopulmonary exercise test (CPET) 6-60 months after BLTx. Physical activity was measured with accelerometers, and results were compared with Norwegian normative data and the World Health Organization's (WHO) recommendations for physical activity. RESULTS: In 54 included BLTx recipients (mean age 50 ± 15 years, 50% females), V∙O2peak (mL × kg-1 × min-1) was 21.8 ± 7.7 for men and 22.4 ± 6.2 for women, corresponding to 57 ± 17 and 70 ± 12% of predicted, respectively. Three patients (6%) met criteria for normal V∙O2peak. Deconditioning limited V∙O2peak in 22 patients (41%), while ventilatory limitation and abnormal gas exchange were observed in 14 (26%) and 20 (37%) patients, respectively (some had more than 1 finding). Forty-three patients (86%) did not meet the WHO physical activity recommendations. There was a moderate correlation between V∙O2peak and physical activity (r = 0.642, p < 0.01). Body mass index, physical activity, forced expiratory volume after 1 second, sex, and hemoglobin together accounted for 73% of the variability in V∙O2peak. CONCLUSIONS: Low cardiorespiratory fitness was observed in the majority of BLTx recipients. Both deconditioning and cardiopulmonary limitations were common findings. Nearly 90% were classified as being inactive according to physical activity recommendations. CPET appears to identify a deconditioned subgroup of BLTx recipients for whom exercise training may be especially beneficial.

Cardiorespiratory fitness, incidence and mortality of lung cancer in men: A prospective cohort study.

OBJECTIVES: To evaluate the association between cardiorespiratory fitness (CRF), lung cancer incidence and cancer mortality in men. DESIGN: Prospective cohort study. METHODS: Maximal exercise testing was performed in 4920 men (59.2±11.4years) free from malignancy at baseline. Multivariate Cox hazard models adjusted for established cancer risk factors including smoking were analyzed for lung cancer incidence and cancer mortality among those who were diagnosed with lung cancer. Population attributable risks (PAR) of low CRF (<5 METs) were determined. RESULTS: During 12.7±7.5years follow-up, 105 (2.1%) participants were diagnosed with lung cancer and 83 (79%) of those died from cancer after 3.6±4.6 years from diagnosis. CRF was inversely and independently associated with cancer outcomes. A 1-MET increase and categories of moderate and high CRF were associated with 10%, 47% and 65% reduction in lung cancer incidence (p=0.002), and 13%, 58% and 76% reduction in cancer mortality (p=0.002), respectively. Also, individuals who were diagnosed with lung cancer and were at moderate or high CRF categories at baseline exhibited longer survival time (p<0.001). The PARs% for lung cancer incidence and cancer mortality were 8.7% and 18.5%, respectively. CONCLUSIONS: Higher CRF is associated with lower lung cancer incidence in men. Among individuals who were diagnosed with lung cancer, higher CRF was associated with reduced cancer mortality and longer survival time. These results support the protective benefits of higher CRF in the prevention of lung cancer outcomes. Eliminating low CRF as a risk factor would potentially prevent considerable lung cancer morbidity and mortality.

Risk factors for impaired pulmonary function and cardiorespiratory fitness in very long-term adult survivors of childhood acute lymphoblastic leukemia after treatment with chemotherapy only.

BACKGROUND: Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk of late treatment-related side-effects. Data regarding prevalence and risk factors for impairments in pulmonary function and cardiorespiratory fitness are limited, and reported findings are inconsistent and inconclusive. MATERIAL AND METHODS: In a cross-sectional study, 116 ALL survivors (median 5 years at diagnosis, 29 years at follow-up, 53% females) were examined, median 23 years after treatment with chemotherapy only. Individual cumulative doses of cytostatic agents were calculated. Methods included blood tests, echocardiography, pulmonary function tests and cardiorespiratory exercise test. RESULTS: Females had lower % predicted gas diffusing capacity (DLCO) than males (mean [SD] 84 [13] versus 97 [14], p < .001). Impairment in DLCO was found in 34% females versus 7% males, p < .001. In a multiple linear regression model, female gender, body mass index (BMI) and smoking were risk factors for reduced % predicted DLCO, with a borderline significant effect of left ventricular ejection fraction (LVEF). Impaired cardiorespiratory fitness was found in 42% of the survivors, with a borderline increased risk in females, p = .06. Smoking and BMI were risk factors for reduced % predicted VO2peak. Subjects exposed to anthracyclines had lower LVEF% and % predicted VO2peak than those not exposed, (mean [SD] 56.2 [4.3] versus 59.2 [5.2], p = .01 and 86.9 [18.4] versus 92.8 [18.4], p = .03, respectively). CONCLUSIONS: Impairments in pulmonary function and cardiorespiratory fitness are common in very long-term survivors of childhood ALL. Risk factors are female gender, BMI and smoking. In order to preserve pulmonary function and cardiorespiratory fitness, we suggest increased attention and targeted advice on modifiable lifestyle factors such as smoking, inactivity and overweight.

Feasibility of a physical activity intervention during and shortly after chemotherapy for testicular cancer.

BACKGROUND: Given the risk of developing acute and long-term adverse effects in patients receiving cisplatin-based chemotherapy for testicular cancer (TC), risk-reducing interventions, such as physical activity (PA), may be relevant. Limited knowledge is available on the challenges met when conducting PA intervention trials in patients with TC during and shortly after chemotherapy. The aims of the present feasibility study are therefore to determine patient recruitment, compliance and adherence to a PA intervention. RESULTS: Patients with metastatic TC referred to cisplatin-based chemotherapy were eligible. They followed an individual low-threshold PA intervention, including counseling from a personal coach during and 3 months after chemotherapy. Outcomes were recruitment rate, compliance rate and adherence to the intervention including preferences for type of PA and barriers for PA. During 8 months 12 of 18 eligible patients were invited, all consented, but three dropped out. Walking and low intensity activities were preferred and nausea and feeling unwell were the most often reported barriers towards PA. DISCUSSION: In order to achieve adequate recruitment, compliance and complete data in future PA intervention trials, close cooperation with treating physicians, individual PA plans and availability of personalized coaching are required. Trial registration NCT01749774, November 2012, ClinicalTrials.gov.

Pre-flight evaluation of adult patients with cystic fibrosis: a cross-sectional study.

BACKGROUND: Air travel may imply a health hazard for patients with cystic fibrosis (CF) due to hypobaric environment in the aircraft cabin. The objective was to identify pre-flight variables, which might predict severe hypoxaemia in adult CF patients during air travel. METHODS: Thirty adult CF-patients underwent pre-flight evaluation with spirometry, arterial oxygen tension (PaO2), pulse oximetry (SpO2) and cardiopulmonary exercise testing (CPET) at sea level (SL). The results were related to the PaO2 obtained during a hypoxia-altitude simulation test (HAST) in which a cabin altitude of 2438 m (8000 ft) was simulated by breathing 15.1% oxygen. RESULTS: Four patients fulfilled the criteria for supplemental oxygen during air travel (PaO2 HAST < 6.6 kPa). While walking slowly during HAST, another eleven patients dropped below PaO2 HAST 6.6 kPa. Variables obtained during CPET (PaO2 CPET, SpO2 CPET, minute ventilation/carbon dioxide output, maximal oxygen uptake) showed the strongest correlation to PaO2 HAST. CONCLUSIONS: Exercise testing might be of value for predicting in-flight hypoxaemia and thus the need for supplemental oxygen during air travel in CF patients. Trial registration The study is retrospectively listed in the ClinicalTrials.gov Protocol Registration System: NCT01569880 (date; 30/3/2012).

Reduction in cardiorespiratory fitness after lung resection is not related to the number of lung segments removed.

AIM: To evaluate the effect of lung cancer surgery on cardiorespiratory fitness (CRF), and to assess the agreement between the predicted postoperative (ppo) V̇O2peak and actually measured postoperative peak oxygen uptake (V̇O2peak). METHODS: Before and 4-6 weeks after lung cancer surgery, 70 patients (35 women) underwent measurements of pulmonary function and CRF via a cardiopulmonary exercise test. In addition, the 23 non-exercising patients underwent measurements after 6 months. The ppo V̇O2peak calculated from the number of functional segments removed was compared with the actually measured postoperative values of V̇O2peak for accuracy and precision. RESULTS: After surgery, the V̇O2peak decreased from 23.9±5.8 to 19.2±5.5 mL/kg/min (-19.6±15.7%) (p<0.001). The breathing reserve increased by 5% (p=0.001); the oxygen saturation remained unchanged (p=0.30); the oxygen pulse decreased by -1.9 mL/beat (p<0.001); the haemoglobin concentration decreased by 0.7 g/dL (p=0.001). The oxygen pulse was the strongest predictor for change in V̇O2peak; adjusted linear squared: r2=0.77. Six months after surgery, the V̇O2peak remained unchanged (-3±15%, p=0.27). The ppo V̇O2peak (mL/kg/min) was 18.6±5.4, and the actually measured V̇O2peak was 19.2±5.5 (p=0.24). However, the limits of agreement were large (CI -7.4 to 8.2). The segment method miscalculated the ppo V̇O2peak by more than ±10 and ±20% in 54% and 25% of the patients, respectively. CONCLUSIONS: The reduction in V̇O2peak and lack of improvement 6 months after lung cancer surgery cannot be explained by the loss of functional lung tissue. Predicting postoperative V̇O2peak based on the amount of lung tissue removed is not recommendable due to poor precision. TRIAL REGISTRATION NUMBER: NCT01748981.

Insulin levels and HOMA index are associated with exercise capacity in patients with type 2 diabetes and coronary artery disease.

BACKGROUND: Previous studies on type 2 diabetes have shown an association between exercise capacity and insulin resistance. In patients with coronary artery disease (CAD) exercise capacity is often reduced due to exercise-induced ischemia. We have investigated the association between glucometabolic control, including the homeostatic model assessment (HOMA) of insulin resistance, and exercise capacity in patients with type 2 diabetes and CAD with and without exercise-induced ischemia. METHODS: In 137 patients (age 63.1 ± 7.9) cardiopulmonary exercise testing on treadmill was performed using a modified Balke protocol. The highest oxygen uptake (VO2peak) was reported as 30-s average. Fasting blood samples were drawn for determination of glucose, insulin and HbA1c. Insulin resistance (IR) was assessed by the HOMA2-IR computer model. Exercise-induced ischemia was defined as angina and/ or ST-depression in ECG ≥ 0.1 mV during the exercise test. RESULTS: HOMA2-IR was inversely correlated to VO2peak (r = -0.328, p < 0.001), still significant after adjusting for age, gender, smoking and BMI. Patients with HOMA2-IR above the median value (1.3) had an adjusted odds ratio of 3.26 (95 % CI 1.35 to 7.83, p = 0.008) for having VO2peak below median (23.8 mL/kg/min). Insulin levels were inversely correlated to VO2peak (r = -0.245, p = 0.010), also after adjusting for age and gender, but not after additional adjustment for BMI. The correlation between HOMA2-IR and VO2peak was also significant in the subgroups with (n = 51) and without exercise-induced ischemia (n = 86), being numerically stronger in the group with ischemia (r = -0.430, p = 0.003 and r = -0.276, p = 0.014, respectively). Fasting glucose and HbA1c were not correlated with VO2peak or AT. CONCLUSIONS: Insulin resistance, as estimated by fasting insulin and the HOMA index, was inversely associated with exercise capacity in patients with type 2 diabetes and CAD, the association being more pronounced in the subgroup with exercise-induced ischemia. These results indicate that insulin resistance is related to exercise capacity in type 2 diabetic patients with CAD, possibly even more so in patients with exercise-induced ischemia compared to those without.