Body mass, cardiorespiratory fitness, and cardiometabolic risk over time: Findings from the Cooper Center Longitudinal Study.

Few studies have adequately assessed the simultaneous effects of changes in cardiorespiratory fitness (fitness) and body mass on cardiometabolic risk. Hence, the current study's aims were twofold: (1) To determine whether increases in body mass result in higher cardiometabolic risk after controlling for fitness changes; and (2) To assess whether increases in fitness result in lower cardiometabolic risk after controlling for weight changes. The study consisted of 3534 patients who came for preventive medicine visits ≥4 times over any 10-year period (1979-2019). The primary independent variables were body mass and fitness, and the dependent variable was metabolic syndrome (MetS) and its components. Mixed-effects regression was used to model the relationship between changes in body mass, fitness, and MetS. Results indicate that increasing body mass up to a 10-year period was significantly related to increasing risk of MetS while controlling for changes in fitness. Specifically, a 1-kg increase in body mass was associated with a 17% (OR = 1.17; 95% CI 1.15-1.19) increased odds for MetS, while adjusting for fitness changes. A 1-MET increase in fitness was related to a 23% (OR = 0.77; 95% CI 0.70-0.84) decrease in odds for MetS, while adjusting for body mass changes up to 10 years. Moreover, body mass change was significantly related to changes in all cardiometabolic components of MetS. Fitness change was significantly associated with changes in MetS components. Future interventions should focus concurrently on increasing fitness and on body mass loss (or maintenance) to improve cardiometabolic health.

Relation of Coronary Artery Diameters With Cardiorespiratory Fitness.

Cardiorespiratory fitness is associated with reduced cardiovascular morbidity and mortality when adjusted for traditional risk factors. Mechanisms by which fitness reduces risk have been studied but remain incompletely understood. We hypothesize that higher fitness is associated with larger coronary artery diameters independent of its effect on traditional risk factors. Two independent measurements of the proximal diameters of the left main, left anterior descending, left circumflex, and right coronary arteries were obtained from gated multidetector computed tomography scans in 500 men from the Cooper Center Longitudinal Study (CCLS). Men with coronary artery calcium scores ≥10 were excluded. Fitness was measured with a maximal exercise treadmill test and reported by quintiles and as a function of METs. We then evaluated the relation between coronary artery diameters and fitness using mixed effect regression models. Higher fitness was associated with larger coronary artery diameters after adjustment for body surface area, smoking status, low-density lipoprotein and high-density lipoprotein cholesterol, resting systolic blood pressure, and serum glucose. When examined continuously, each MET increase in fitness was associated with a mean 0.03 ± 0.01 mm larger diameter of the left main, a 0.04 ± 0.01 mm larger diameter of the left anterior descending, a 0.05 ± 0.01 mm larger diameter of the left circumflex, and a 0.07 ± 0.01 mm larger diameter of the right coronary artery (p = 0.002). This correlation between fitness and coronary artery diameters was most prominent for fitness levels above 10 METs. In conclusion, higher fitness is associated with larger coronary artery diameters.

Dietary Patterns and Long-Term Survival: A Retrospective Study of Healthy Primary Care Patients.

BACKGROUND: Dietary patterns are related to mortality in selected populations with comorbidities. We studied whether dietary patterns are associated with long-term survival in a middle-aged, healthy population. METHODS: In this observational cohort study at the Cooper Clinic preventive medicine center (Dallas, Tex), a volunteer sample of 11,376 men and women with no history of myocardial infarction or stroke completed a baseline dietary assessment between 1987 and 1999 and were observed for an average of 18 years. Proportional hazard regressions, including a tree-augmented model, were used to assess the association of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern, Mediterranean dietary pattern, and individual dietary components with mortality. The primary outcome was all-cause mortality. The secondary outcome was cardiovascular mortality. RESULTS: Mean baseline age was 47 years. Each quintile increase in the DASH diet score was associated with a 6% lower adjusted risk for all-cause mortality (P < .02). The Mediterranean diet was not independently associated with all-cause or cardiovascular mortality. Solid fats and added sugars were the most predictive of mortality. Individuals who consumed >34% of their daily calories as solid fats had the highest risk for all-cause mortality. CONCLUSIONS: The DASH dietary pattern was associated with significantly lower all-cause mortality over approximately 2 decades of follow-up in a middle-aged, generally healthy population. Added solid fat and added sugar intake were the most predictive of all-cause mortality. These results suggest that promotion of a healthy dietary pattern should begin in middle age, before the development of comorbid risk factors.

Moderate to High Levels of Cardiorespiratory Fitness Attenuate the Effects of Triglyceride to High-Density Lipoprotein Cholesterol Ratio on Coronary Heart Disease Mortality in Men.

OBJECTIVE: To examine the prospective relationships among cardiorespiratory fitness (CRF), fasting blood triglyceride to high density lipoprotein cholesterol ratio (TG:HDL-C), and coronary heart disease (CHD) mortality in men. METHODS: A total of 40,269 men received a comprehensive baseline clinical examination between January 1, 1978, and December 31, 2010. Their CRF was determined from a maximal treadmill exercise test. Participants were divided into CRF categories of low, moderate, and high fit by age group and by TG:HDL-C quartiles. Hazard ratios for CHD mortality were computed using Cox regression analysis. RESULTS: A total of 556 deaths due to CHD occurred during a mean ± SD of 16.6±9.7 years (669,678 man-years) of follow-up. A significant positive trend in adjusted CHD mortality was shown across decreasing CRF categories (P for trend<.01). Adjusted hazard ratios were significantly higher across increasing TG:HDL-C quartiles as well (P for trend<.01). When grouped by CRF category and TG:HDL-C quartile, there was a significant positive trend (P=.04) in CHD mortality across decreasing CRF categories in each TG:HDL-C quartile. CONCLUSION: Both CRF and TG:HDL-C are significantly associated with CHD mortality in men. The risk of CHD mortality in each TG:HDL-C quartile was significantly attenuated in men with moderate to high CRF compared with men with low CRF. These results suggest that assessment of CRF and TG:HDL-C should be included for routine CHD mortality risk assessment and risk management.

High Cardiorespiratory Fitness Is Associated with Reduced Risk of Low Bone Density in Postmenopausal Women.

PURPOSE: The goal of this study was to determine the association between cardiorespiratory fitness (CRF) and bone mineral density (BMD) of the femoral neck (FN) in postmenopausal women using existing Cooper Center Longitudinal Study data. MATERIALS AND METHODS: A cohort of 1,720 predominantly healthy Caucasian women (57.1 ± 6.9 years) underwent preventive medical examinations that included CRF assessment by maximal Balke treadmill testing and measurement of BMD by dual-energy X-ray absorptiometry. CRF was estimated from total treadmill time and categorized into five categories of CRF (further defined as fitness category 1 = low fitness, 2-3 = moderate fitness, and 4-5 = high fitness). Logistic regression was used to characterize the association between CRF and BMD, adjusting for age, weight, and resistance activity level. RESULTS: Overall, the mean body-mass index (BMI) for all subjects was 25.0 ± 4.5 kg/m2, although BMI was in the obese range in the low fitness group. The prevalence of osteoporosis (T-score ≤ -2.5 at the FN) was greater in the low fit group than moderate or high fit (5.8% vs. 3.0% or 3.9%, respectively); with a similar pattern seen for prevalence of osteopenia (T-score > -2.5 and ≤ -1.0 at the FN) (47.5% vs. 46.4% or 44.8%, respectively). Higher age and lower weight were associated with low BMD. Fully adjusted logistic regression models showed an inverse association between CRF and low BMD of the FN. For T-score ≤ -1.0, the primary outcome, the odds ratio (OR) was 0.50 (95% confidence interval [CI] 0.32-0.79) for moderate fitness, and OR of 0.32 (95% CI 0.21-0.51) for high fitness was seen. For T-score ≤ -2.5 at the FN, OR was 0.30 (95% CI 0.11-0.80) for moderate fitness, and OR was 0.29 (95% CI 0.12-0.71) for high fitness. CONCLUSION: Increased CRF levels are associated with reduced risk for low bone density in postmenopausal women.

The Relationship Between Cardiorespiratory Fitness and Bone Mineral Density in Men: A Cross-sectional Study.

OBJECTIVE: To determine the relationship between estimated cardiorespiratory fitness (CRF) and femoral neck (FN) bone mineral density (BMD) in men. PATIENTS AND METHODS: This cross-sectional study included 2569 men aged 50 to 90 years (mean, 63.5 years) who had at least 1 health examination at a preventive medicine clinic between January 27, 1998, and February 24, 2015. Maximal treadmill tests were conducted using the Balke protocol and were used to estimate CRF. We stratified patients into low, moderate, and high CRF categories. The FN BMD was measured by dual-energy x-ray absorptiometry. Odds ratios (ORs) for T-scores of -2.5 or less (osteoporosis) and -1.0 or less (low BMD) were calculated for categorical CRF and were adjusted for weight, age, and days per week of resistance activity. RESULTS: The sample prevalence of osteoporosis in the FN was 4.1% and of low BMD was 49.4%. There was a significant inverse association between higher CRF category and osteoporosis measured at the FN (moderate vs low: OR=0.34; 95% CI, 0.16-0.74; high vs low: OR=0.19; 95% CI, 0.09-0.42) and low BMD (moderate vs low: OR=0.64; 95% CI, 0.43-0.96; high vs low: OR=0.43; 95% CI, 0.29-0.65). CONCLUSION: In men, CRF is directly associated with BMD. These results suggest that moderate-to-high CRF levels attained through regular physical activity may attenuate age-related decline in BMD. Further studies are needed to determine whether this translates to a lower risk of osteoporotic fracture in more fit men.

Association between omega-3 fatty acids and serum prostate-specific antigen.

We examined the association between omega-3 fatty acids (O3FAs) and prostate-specific antigen (PSA) in a cross-sectional analysis of 6219 men examined at the Cooper Clinic from 2009 to 2013. We assayed O3FAs from red blood cell membranes and measured PSA levels in study participants. Multiple logistic regression was used to examine the association between O3FAs and PSA. The mean age of study participants was 55.5 years (SD = 9.8) with a mean PSA level of 1.31 ng/mL (SD = 1.5). Unadjusted analyses indicated that there was a slight, direct association with PSA and each of the O3FAs tested. However, after adjusting for age and body mass index (BMI), the associations were reversed but nonsignificant [odds ratio (OR) for PSA > 4 ng/mL: total omega-3 OR = 0.98 per each 1% of total fatty acids, 95% confidence interval (CI) = 0.93-1.03; docosahexaenoic acid OR = 1.01, 95% CI = 0.92-1.11; omega-3 index OR = 0.99, 95% CI = 0.93-1.05). Similar results were obtained after age and BMI adjustment when the omega-3 index was divided into undesirable (0.01-3.99%), intermediate (4.0-7.99%), and desirable ranges ( ≥ 8.0%). Given that the study had >80% power to detect an odds ratio <0.9 or >1.1, we conclude that associations between O3FAs and PSA levels are either nonexistent or quite weak in the population that this healthy sample represents.

Independent and joint effects of sedentary time and cardiorespiratory fitness on all-cause mortality: the Cooper Center Longitudinal Study.

OBJECTIVES: To examine the independent and joint effects of sedentary time and cardiorespiratory fitness (fitness) on all-cause mortality. DESIGN, SETTING, PARTICIPANTS: A prospective study of 3141 Cooper Center Longitudinal Study participants. Participants provided information on television (TV) viewing and car time in 1982 and completed a maximal exercise test during a 1-year time frame; they were then followed until mortality or through 2010. TV viewing, car time, total sedentary time and fitness were the primary exposures and all-cause mortality was the outcome. The relationship between the exposures and outcome was examined utilising Cox proportional hazard models. RESULTS: A total of 581 deaths occurred over a median follow-up period of 28.7 years (SD=4.4). At baseline, participants' mean age was 45.0 years (SD=9.6), 86.5% were men and their mean body mass index was 24.6 (SD=3.0). Multivariable analyses revealed a significant linear relationship between increased fitness and lower mortality risk, even while adjusting for total sedentary time and covariates (p=0.02). The effects of total sedentary time on increased mortality risk did not quite reach statistical significance once fitness and covariates were adjusted for (p=0.05). When examining this relationship categorically, in comparison to the reference category (≤10 h/week), being sedentary for ≥23 h weekly increased mortality risk by 29% without controlling for fitness (HR=1.29, 95% CI 1.03 to 1.63); however, once fitness and covariates were taken into account this relationship did not reach statistical significance (HR=1.20, 95% CI 0.95 to 1.51). Moreover, spending >10 h in the car weekly significantly increased mortality risk by 27% in the fully adjusted model. The association between TV viewing and mortality was not significant. CONCLUSIONS: The relationship between total sedentary time and higher mortality risk is less pronounced when fitness is taken into account. Increased car time, but not TV viewing, is significantly related to higher mortality risk, even when taking fitness into account, in this cohort.

Standing, Obesity, and Metabolic Syndrome: Findings From the Cooper Center Longitudinal Study.

OBJECTIVE: To examine the cross-sectional relationships between standing time, obesity, and metabolic syndrome alongside and independent of leisure-time physical activity (LTPA). PARTICIPANTS AND METHODS: The primary study sample consisted of 7075 adult patients (aged 20-79 years) from Cooper Clinic (Dallas, Texas). In this cross-sectional study we assessed the associations between reported standing time and directly measured obesity (body mass index ≥ 30), elevated waist circumference (men: ≥ 102 cm; women: ≥ 88 cm), body fat percentage (men: ≥ 25%; women ≥ 30%), and metabolic syndrome (yes/no). In addition, the joint associations of standing and LTPA on each outcome were examined. Multivariable logistic regression adjusting for confounders was used for statistical analyses. RESULTS: Standing a quarter of the time or more was significantly associated with reduced odds of an elevated body fat percentage in men (P < .001) and a reduced likelihood of obesity (P < .009) and abdominal obesity (P=.04) in women. In addition, joint association analyses indicated that compared with the reference group (ie, not meeting the physical activity guidelines/standing almost none of the time), men and women who met the physical activity guidelines had lower odds of all obesity outcomes and metabolic syndrome with incremental additions of standing time (ie, a dose-response relationship). CONCLUSION: Standing a quarter of the time per day or more is associated with reduced odds of obesity. The inverse relationship of standing to obesity and metabolic syndrome is more robust when combined with health-promoting LTPA. Prospective studies are warranted to confirm these findings and establish a causal relationship.

The association of fitness with reduced cardiometabolic risk among smokers.

INTRODUCTION: Despite the health benefits associated with smoking cessation, continued smoking and relapse following cessation are common. Physical activity is associated with reduced risk of cardiovascular disease in general, though less is known about how cardiorespiratory fitness may influence cardiometabolic risk among smokers. Strategies are needed to protect against the health consequences of smoking among those unwilling or unable to quit smoking. The purpose of this study is to determine whether greater cardiorespiratory fitness is associated with reduced metabolic risk among smokers. METHODS: The prospective influence of estimated cardiorespiratory fitness (i.e., maximal METs) on the development of metabolic syndrome and its components were examined among adult smokers (N=1,249) who completed at least two preventive medical visits at the Cooper Clinic (Dallas TX) between 1979 and 2011. Statistical analyses were completed in 2013 and 2014. RESULTS: The rate and risk for metabolic syndrome, as well as abnormal fasting glucose and high-density lipoprotein cholesterol levels declined linearly with increases in cardiorespiratory fitness (all p<0.05). Smokers in the moderate and high fitness categories had significantly reduced risk of developing metabolic syndrome and elevated fasting glucose relative to smokers in the lowest fitness category. In addition, smokers in the high fitness category were less likely to develop abnormal high-density lipoprotein cholesterol levels. CONCLUSIONS: Moderate to high cardiorespiratory fitness among smokers is associated with a reduced likelihood of developing certain cardiovascular disease risk factors and metabolic syndrome.

Is There a Gradient of Mortality Risk among Men with Low Cardiorespiratory Fitness?

PURPOSE: A low level of cardiorespiratory fitness (CRF) is a strong and independent predictor of all-cause mortality in men; however, it is unknown whether a gradient of mortality risk exists within the lowest CRF category. METHODS: A total of 6251 apparently healthy men (mean age, 48.7 ± 6.3 yr) completed a comprehensive baseline clinical examination, including a maximal treadmill exercise test at Cooper Clinic between 1971 and 2006. In accord with previous studies using this cohort, low CRF was defined as a treadmill time in the first quintile within each age category of 40-49, 50-59, and 60-69 yr. The low CRF cohort was then grouped by tertiles (low/low, LL; mid/low, ML; and high/low, HL) using the same age categories. RESULTS: After a mean follow-up period of 19.1 ± 10.4 yr, 1259 deaths occurred. Adjusted all-cause mortality rates were 57.0, 31.1, and 34.4 deaths per 10,000 man-years across LL, ML, and HL CRF categories for the 40- to 49-yr-old age group (P trend = 0.007). Similar trends were seen across low CRF categories for the 50- to 59-yr-old and 60- to 69-yr-old age groups (P trend = 0.02 and 0.09, respectively). When using treadmill time as a continuous variable, each 1-min increment in treadmill time was associated with a 9%, 11%, and 15% reduction in risk of all-cause mortality among low-CRF men in the 40-49, 50-59, and 60-69 age groups, respectively. CONCLUSIONS: An inverse trend in all-cause mortality exists among men across LL, ML, and HL CRF groups. Although all low-fit men should be targeted for physical activity intervention, it is especially important to target the LL CRF group.

Physical activity versus cardiorespiratory fitness: two (partly) distinct components of cardiovascular health?

Physical activity (PA) and cardiorespiratory fitness (CRF) both have inverse relationships to cardiovascular (CV) morbidity and mortality. Recent position papers and guidelines have identified the important role of both of these factors in CV health. The benefits of PA and CRF in the prevention of CV disease and risk factors are reviewed. In addition, assessment methodology and utilization in the research and clinical arenas are discussed. Finally, the benefits, methodology, and utilization are compared and contrasted to better understand the two (partly) distinct components and their impact on CV health.

Sedentary behavior, cardiorespiratory fitness, physical activity, and cardiometabolic risk in men: the cooper center longitudinal study.

OBJECTIVE: To examine the association between sedentary behavior and cardiometabolic risk, while taking into account cardiorespiratory fitness (fitness) and physical activity. PARTICIPANTS AND METHODS: We examined the association of sedentary behavior, physical activity, and fitness (exposure variables) to cardiometabolic biomarkers and metabolic syndrome (outcome measures) among a historic cohort (January 2, 1981, through October 16, 2012) of men. First, we estimated the association (cross-sectionally and longitudinally) of sedentary behavior along with physical activity and fitness to lipids and lipoproteins, glucose, blood pressure, and markers of adiposity, including body mass index, waist circumference, and body fat percentage. We then prospectively examined the effects of baseline sedentary time on the incidence of metabolic syndrome, while adjusting for physical activity, fitness, and other covariates in multivariate models. RESULTS: Multivariate analysis of baseline data revealed that in comparison with the reference group (≤9 h/wk of sedentary time), more sedentary behavior was significantly associated with a higher triglyceride level, a higher triglycerides-high-density lipoprotein cholesterol ratio, and a higher body mass index, waist circumference, and body fat percentage (P<.05 for trend), after adjusting for physical activity and covariates. When adjusting for fitness and covariates, prolonged sedentary time was only associated with a higher triglyceride-high-density lipoprotein cholesterol ratio (P=.02 for trend). Sedentary time was not associated with the incidence of metabolic syndrome in multivariate models. Longitudinal analyses revealed that a 1-metabolic equivalent increase in fitness was significantly (P<.05) associated with almost all biomarkers when adjusting for sedentary behavior, with little moderation observed. CONCLUSION: The association between prolonged sedentary time and cardiometabolic biomarkers is markedly less pronounced when taking fitness into account. Further exploration of the effects of sedentary behavior on cardiometabolic risk is warranted in cohorts with available fitness data. Furthermore, our findings underscore the need to encourage achieving higher fitness levels through meeting physical activity guidelines to decrease disease risk factors.

Association of multiple adiposity exposures and cardiorespiratory fitness with all-cause mortality in men: the Cooper Center Longitudinal Study.

OBJECTIVE: To examine the additive effects of an increased number of positive adiposity exposures on all-cause mortality in men before and after stratification by cardiorespiratory fitness (CRF) level. PATIENTS AND METHODS: A total of 36,836 men underwent a physical examination at the Cooper Clinic from January 1, 1971, through December 31, 2006. Exposures included body mass index, waist circumference, percentage of body fat, and CRF as determined by duration of a maximal exercise test. Participants were identified as being either obese (positive) or nonobese (negative) for each adiposity exposure and then grouped into 4 categories: group 1, negative for all adiposity exposures; group 2, positive for any 1 exposure; group 3, positive for any 2 exposures; and group 4, positive for all exposures. Then CRF was grouped as fit or unfit on the basis of the upper 80% and lower 20% of the age-standardized CRF distribution as previously reported in the Cooper Center Longitudinal Study. Hazard ratios were computed with Cox regression analysis. RESULTS: A total of 2294 deaths occurred during a mean ± SD of 15.5 ± 8.1 years of follow-up. Adjusted hazard ratios across adiposity groups were 1.0 (referent), 1.05, 1.37, and 1.87 for groups 1 through 4, respectively (P for trend <.001). Mortality rates were significantly lower within each of the first 3 adiposity groups in fit compared with unfit men (P<.009 for all comparisons). CONCLUSION: An increasing number of positive adiposity exposures were associated with increased mortality in men. Because moderate to high CRF attenuated mortality rates in all adiposity groups, measurement of CRF should be included for identifying men at increased risk for all-cause mortality.

Cardiorespiratory fitness, body mass index, and heart failure mortality in men: Cooper Center Longitudinal Study.

BACKGROUND: We evaluated the individual and joint associations among cardiorespiratory fitness (CRF), body mass index, and heart failure (HF) mortality, as well as the additive effect of an increasing number of cardiovascular risk factors on HF mortality in fit versus unfit men. METHODS AND RESULTS: A total of 44 674 men without a history of cardiovascular disease underwent a baseline examination between 1971 and 2010. Measures included body mass index and CRF quantified as duration of maximal treadmill exercise testing. Participants were divided into age-specific low, moderate, and high CRF categories. Hazard ratios were computed with Cox regression analysis. During a mean follow-up of 19.8±10.4 years, 153 HF deaths occurred. Adjusted hazard ratios across high, moderate, and low CRF categories were 1.0, 1.63, and 3.97, respectively, whereas those of normal, overweight, and obese body mass index categories were 1.0, 1.56, and 3.71, respectively (P for trend <0.0001 for each). When grouped into categories of fit and unfit (upper 80% and lower 20% of CRF distribution, respectively), hazard ratios were significantly lower in fit compared with unfit men in normal and overweight body mass index strata (P<0.002) but not in obese men. Within men matched for the same number of HF risk factors, fit men had significantly lower HF mortality than unfit men (P≤0.02). CONCLUSIONS: Higher baseline CRF is associated with lower HF mortality risk in men, regardless of the number of HF risk factors present. Men should be counseled on physical activity with the goal of achieving at least a moderate level of CRF, thereby presumably decreasing their risk of HF mortality.

Cardiorespiratory fitness, alcohol intake, and metabolic syndrome incidence in men.

PURPOSE: The objective of this study is to prospectively examine the independent and joint effects of alcohol consumption and cardiorespiratory fitness on the incidence of metabolic syndrome (MetS) in a cohort of men. METHODS: A prospective examination was done of 3411 apparently healthy men at baseline, who came to the Cooper Clinic (Dallas, TX) for at least two preventive visits (1979-2010). Primary exposure variables were cardiorespiratory fitness and alcohol intake; the outcome measure was MetS and the components thereof. Cox proportional hazards models were computed to assess the relation between the exposure variables and the incidence of MetS while adjusting for confounders. RESULTS: For a mean follow-up period of 9 yr (SD = 7.8), 276 men developed MetS. In multivariable analysis, a dose-response relationship was observed between increased levels of fitness and reduced MetS risk (moderate fitness: HR = 0.60; 95% confidence interval (CI), 0.43-0.82; high fitness: HR = 0.49, 95% CI, 0.35-0.69). When examining the independent effects of alcohol, light drinking increased the risk for MetS by 66% (HR = 1.66, 95% CI, 1.11-2.48). No statistically significant interaction effect was observed between alcohol and fitness in relation to MetS (P = 0.32). When assessing the relation between each exposure and the components of MetS, higher fitness consistently reduced the risk of all components, whereas lower alcohol intake reduced the risk of elevated glucose and blood pressure and increased the risk for low HDL cholesterol. CONCLUSIONS: Among this cohort of men, higher fitness levels reduced the risk for MetS and its components. The relation between alcohol intake levels and metabolic risk was more complex and not reflected when examining MetS as a whole.

Cardiorespiratory fitness, LDL cholesterol, and CHD mortality in men.

INTRODUCTION: There are no published data regarding the joint association of cardiorespiratory fitness (CRF) and LDL cholesterol concentration with subsequent CHD mortality in men. METHODS: A total of 40,718 healthy men received a comprehensive baseline clinical examination between 1971 and 2006. CRF was determined from a maximal treadmill exercise test. Participants were divided into categories of low (quintile 1), moderate (quintiles 2-3), and high (quintiles 4-5) CRF by age group, as well as by Adult Treatment Panel III-defined LDL categories. HRs for CHD mortality were computed with Cox regression analysis. RESULTS: A total of 557 deaths due to CHD occurred during 16.7 ± 9.0 yr (681,731 man-years) of follow-up. After adjustment for age, examination year, smoking status, family history, and body mass index, a significant positive trend in CHD mortality was shown across decreasing categories of CRF. HRs with 95% confidence interval were 1.0 (referent), 1.18 (0.94-1.47), and 2.10 (1.65-2.67) for high, moderate, and low fit groups, P trend <0.0001. Adjusted HRs were significantly higher across increasing LDL categories: 1.0 (referent), 1.30 (0.87-1.95), 1.54 (1.04-2.28), 2.16 (1.45-3.21), and 2.02 (1.31-3.13), P trend <0.0001. When grouped by CRF category as well as by LDL category, there was a significant positive trend (P < 0.02) in adjusted mortality across decreasing categories of CRF within each LDL category. CONCLUSIONS: CRF is strongly and inversely associated with CHD mortality in men. Compared with men with low CRF, at a moderate to high level of CRF, the risk of mortality within each LDL category is significantly attenuated. This study suggests that measurement of CRF should be considered for routine cardiovascular risk assessment and risk management.

Computerized self-monitoring and technology-assisted feedback for weight loss with and without an enhanced behavioral component.

OBJECTIVE: The purpose of this study was to develop and evaluate a 12-week weight management intervention involving computerized self-monitoring and technology-assisted feedback with and without an enhanced behavioral component. METHODS: 120 overweight (30.5±2.6kg/m(2)) adults (45.0±10.3 years) were randomized to one of three groups: computerized self-monitoring with Basic feedback (n=45), Enhanced behavioral feedback (n=45), or wait-list control (n=30). Intervention participants used a computer software program to record dietary and physical activity information. Weekly e-mail feedback was based on computer-generated reports, and participants attended monthly measurement visits. RESULTS: The Basic and Enhanced groups experienced significant weight reduction (-2.7±3.3kg and -2.5±3.1kg) in comparison to the Control group (0.3±2.2; p<0.05). Waist circumference and systolic blood pressure also decreased in intervention groups compared to Control (p<0.01). CONCLUSIONS: A program using computerized self-monitoring, technology-assisted feedback, and monthly measurement visits produced significant weight loss after 12 weeks. However, the addition of an enhanced behavioral component did not improve the effectiveness of the program. PRACTICE IMPLICATIONS: This study suggests that healthcare professionals can effectively deliver a weight management intervention using technology-assisted strategies in a format that may complement and reduce face-to-face sessions.

Cardiorespiratory fitness, different measures of adiposity, and total cancer mortality in women.

The objective was to examine associations among cardiorespiratory fitness (CRF), adiposity, and cancer mortality in women. Healthy women (N = 14,256) without cancer history completed a baseline health examination 1970-2005. Measures included BMI, percent body fat (%Fat), and CRF quantified as duration of a maximal treadmill test. CRF was classified as low (quintile 1), moderate (Q2-3), and high fit (Q4-5) by age. Standard BMI cutpoints were used, while participants were classified by %Fat quintiles. Cancer mortality rates were calculated following age, exam year, and smoking adjustment. During a mean follow-up period of 15.2 ± 9.4 years, 250 cancer deaths occurred. Adjusted mortality rates across BMI groups were 4.6, 5.7, and 8.8 (P trend 0.08); %Fat 3.0, 4.9, 2.9, 3.8, and 6.9 (P trend 0.17); and CRF 7.9, 5.5, and 2.9 (P trend 0.003). When grouped into categories of fit and unfit (upper 80% and lower 20% of CRF distribution), and using BMI as the adiposity exposure, cancer mortality rates of unfit-obese women were significantly higher than fit-normal weight women (9.8 vs. 4.1 deaths/10,000 woman-years; P = 0.02), while fit-overweight and fit-obese women had no greater risk of mortality than fit-normal weight women. Using %Fat as the adiposity exposure, unfit-obese women tended to have higher cancer mortality than fit-normal weight women (7.0 vs. 3.3 deaths/10,000 woman-years, P = 0.10). Higher levels of CRF are associated with lower cancer mortality risk in women and attenuate the risk of cancer mortality in overweight women. Using adiposity measures to estimate cancer mortality risk in women can be potentially misleading unless CRF is considered.

Glycemic index, glycemic load, and prevalence of the metabolic syndrome in the cooper center longitudinal study.

OBJECTIVE: Previous research examining the relationships among glycemic index, glycemic load, and the metabolic syndrome has resulted in inconsistent findings. The objective of this study was to examine whether glycemic index and glycemic load are associated with prevalent metabolic syndrome and its components after adjustment for cardiorespiratory fitness, an objective measure of physical activity habitus. DESIGN: Cross-sectional study. SUBJECTS/SETTING: Women (n=1,775) and men (n=9,137) who completed a comprehensive medical examination between October 1987 and March 1999, including maximal treadmill exercise test and 3-day dietary records at the Cooper Clinic, Dallas, TX. MAIN OUTCOME MEASURES: Metabolic syndrome and its components, defined by the revised Adult Treatment Panel III criteria. STATISTICAL ANALYSIS: Multiple logistic regression models were used to estimate sex-specific odds ratios and 95% confidence intervals to evaluate the associations among glycemic index, glycemic load, and prevalent metabolic syndrome and its components, while adjusting for potential confounding variables. RESULTS: Prevalence of metabolic syndrome was 24% in men and 9% in women. A positive association across quintiles of glycemic index and metabolic syndrome, elevated triglycerides, and low high-density lipoprotein cholesterol (HDL-C) in men was observed in the fully adjusted model (P for trend<0.05). In women, glycemic index was positively associated with large waist girth, low HDL-C, and elevated triglycerides (P for trend<0.05 for all) after multivariate adjustment including cardiorespiratory fitness. Glycemic load was positively associated with elevated triglycerides and low HDL-C (P for trend<0.0001) and inversely associated with prevalence of large waist girth and elevated glucose (P for trend<0.0001) in men. Among women, glycemic load was positively associated with elevated triglycerides (P for trend=0.04) and low HDL-C (P for trend<0.0001) in the multivariate model including cardiorespiratory fitness. CONCLUSIONS: A lifestyle that includes a low glycemic diet can improve metabolic risk profiles in men and women. Prospective studies examining glycemic index, glycemic load, and metabolic syndrome that control for cardiorespiratory fitness are needed.