Personalized Activity Intelligence (PAI) for prevention of cardiovascular disease and promotion of physical activity

Purpose To derive and validate a single metric of activity tracking that associates with lower risk of cardiovascular disease mortality. Methods We derived an algorithm, Personalized Activity Intelligence (PAI), using the HUNT Fitness Study (n\ua0= 4631), and validated it in the general HUNT population (n\ua0= 39,298) aged 20-74 years. The PAI was divided into three sex-specific groups (≤50, 51-99, and ≥100), and the inactive group (0 PAI) was used as the referent. Hazard ratios for all-cause and cardiovascular disease mortality were estimated using Cox proportional hazard regressions. Results After >1 million person-years of observations during a mean follow-up time of 26.2 (SD 5.9) years, there were 10,062 deaths, including 3867 deaths (2207 men and 1660 women) from cardiovascular disease. Men and women with a PAI level ≥100 had 17% (95% confidence interval [CI], 7%-27%) and 23% (95% CI, 4%-38%) reduced risk of cardiovascular disease mortality, respectively, compared with the inactive groups. Obtaining ≥100 PAI was associated with significantly lower risk for cardiovascular disease mortality in all prespecified age groups, and in participants with known cardiovascular disease risk factors (all P-trend

Risk of atrial fibrillation and stroke among older men exposed to prolonged endurance sport practice: a 10-year follow-up. The Birkebeiner Ageing Study and the Tromsø Study

Aims Endurance sport practice is associated with a high prevalence of atrial fibrillation (AF), which increases the risk of stroke in the general population. However, stroke risk in endurance athletes with AF is sparsely investigated. Most studies have been limited by design and are largely restricted to younger and middle-aged populations. Thus, we aimed to investigate AF and stroke risk in older athletes exposed to prolonged endurance training. Method During a 10-year period, 505 male athletes aged ≥65 years frequently participating in a long-distance ski race were compared with 1867 men of the same age from the general population. The main exposure was endurance sport practice with self-reported AF and stroke as outcomes. Stroke risk was further examined by joint modelling of AF and endurance practice. Statistical analysis was conducted with a modified Poisson model. Results Athletes (median age: 68, range: 65–90) participated in a long-distance ski race over a median of 14 years (range: 1–53). Prevalence (28.5% vs 17.8%) and adjusted risk of AF (risk ratio (RR): 1.88, 95% CI: 1.49 to 2.37) were higher in athletes compared with non-athletes, whereas the prevalence (5.4% vs 9.7%) and risk of stroke were lower (RR: 0.60, 95% CI: 0.37 to 0.95). Compared with athletes without AF, risk of stroke was twofold in athletes (RR: 2.38, 95% CI: 1.08 to 5.24) and nearly fourfold in non-athletes (RR: 3.87, 95% CI: 1.98 to 7.57) with AF. Conclusion Although older male endurance athletes experienced an increased risk of AF, the long-term risk of stroke was substantially reduced compared with non-athletes

Peak oxygen uptake and habitual exercise as a basis for primary prevention

Maksimalt oksygenopptak (VO2peak) er rekna som ein av dei viktigaste prognostiske markørane for framtidig hjarte-/karsjukdom og tidleg død. Ettersom direkte måling av VO2peak er tidkrevjande og kostbart har implementeringa i førebyggjande helsearbeid og klinisk praksis vore begrensa. Både VO2peak og ei rekkje andre sentrale helseparameter, kan betrast ved ei viss mengd fysisk aktivitet i kvardagen, og dagens globale anbefalingar er at alle vaksne bør utføre minst 150 minutt med moderat intensitet eller minst 75 minutt med høg intensitet per veke. Utforminga av anbefalingane inneber at det totale energiforbruket, og dermed helsegevinstane, kan oppnås ved ulike tilnærmingar der kortare varigheit kan kompenserast med høgare intensitet og vice versa. I dette prosjektet nytta me data på direkte målt VO2peak frå 4631 deltakarar i den siste Helseundersøkelsen i Nord-Trøndelag (HUNT 3, 2006-08) til først å utvikle ein prediksjonsmodell for å kunne estimere VO2peak og vidare undersøke om denne modellen kunne predikere framtidig hjerte-/kardødeligheit og død uansett årsak i ein stor befolkning. Me såg vidare på korleis ulike tilnærmingar til dagens anbefalingar for fysisk aktivitet var assosiert med direkte målt VO2peak i utvalet frå HUNT. Hovedfunna i avhandlinga er at VO2peak kan estimerast relativt nøyaktig ved ein regresjonsmodell med lett tilgjengelige variablar som alder, kroppssamansetning, fysisk aktivitetsnivå og kvilepuls og at modellen kan nyttast til å kategorisere personar med låg eller høg direkte målt VO2peak. Denne modellen vart nytta til å estimere VO2peak i eit stort utval friske deltakarar frå HUNT 1 (1984-86) som vart fulgt fram til registrert dødsdato eller slutten av 2010. For kvar 3,5 mL∙kg-1∙min-1 høgare estimert VO2peak var risikoen for død av hjarte- /karsjukdom 21 % lågare for personar av begge kjønn som var under 60 år ved undersøkelsen, medan risikoen uansett dødsårsak var henholdsvis 15 % og 8 % lågare for menn og kvinner. Vidare viser me at grupper som rapporterer fysisk aktivitetsvanar i tråd med dagens anbefalingar, anten ved moderat relativ intensitet over lengre tid eller høg intensitet over kortare tid, i gjennomsnitt hadde tilfredsstillande høg og tilnærma lik VO2peak. Samtidig viser me at eit relativt begrensa antal personar som rapporterte ein tidsbruk under minimum anbefaling, men med svært høg relativ intensitet, også hadde tilsvarande høg VO2peak. Også når tidsbruken eller det samla energiforbruket var konstant fann me at dei som rapporterte høg intensitet hadde høgare VO2peak enn dei som rapporterte låg eller moderate intensitet.Directly measured peak oxygen uptake (VO2peak) is established as an important prognostic marker of cardiovascular disease and premature mortality, but is rarely evaluated for prevention purposes or in primary care settings due to costly and time-consuming procedures. Both VO2peak and several other health parameters can, however, be improved and maintained by regular exercise, and today`s recommendations suggest that all adults should do at least 150 minutes of moderate intensity or 75 minutes or vigorous intensity exercise per week. Hence, the total recommended volume or energy expenditure may be reached by strictly different approaches. In the current thesis, data on directly measured VO2peak in 4631 individuals from the third wave of the Nord-Trøndelag Health Study (HUNT 3, 2006-08), were used to first derive a simple prediction model for VO2peak that potentially could supplement direct measurements in healthcare settings and for research purposes. Next, the clinical utility of this model was examined by its ability to predict all-cause and cardiovascular mortality in a large sample of healthy men and women from the HUNT 1 (1984-86) cohort. Furthermore, we examined how different combinations of intensity and total time spent at habitual exercise were associated with VO2peak in apparently healthy, community dwelling individuals from HUNT 3. The findings in this thesis indicate that VO2peak can be predicted with reasonable accuracy by using easily available clinical and selfreported variables such as age, body composition, self-reported physical activity and resting heart rate, and that the model can be used to correctly classify subjects in the correct tail of the VO2peak distribution. For each metabolic equivalent (i.e. MET, ~3.5 mL∙kg-1∙min-1) higher CRF, the risk of CVD mortality was 21% lower in both men and women who were below 60 years at baseline, while the corresponding risk of all-cause mortality was 15% and 8% lower in men and women, respectively, for each MET higher CRF. Furthermore, we demonstrate that habitual exercise patterns of moderate intensity for a long total duration or vigorous intensity for a relatively short duration, adding up to the total volume as recommended by the health authorities, both were associated with a beneficial VO2peak –level. However, a higher VO2peak was observed among those reporting vigorous intensity compared to low and moderate intensity for a similar time spent, and energy expenditure used during exercise

Predicting VO2peak from Submaximal- and Peak Exercise Models: The HUNT 3 Fitness Study, Norway

Purpose Peak oxygen uptake (VO2peak) is seldom assessed in health care settings although being inversely linked to cardiovascular risk and all-cause mortality. The aim of this study was to develop VO2peak prediction models for men and women based on directly measured VO2peak from a large healthy population Methods VO2peak prediction models based on submaximal- and peak performance treadmill work were derived from multiple regression analysis. 4637 healthy men and women aged 20–90 years were included. Data splitting was used to generate validation and cross-validation samples. Results The accuracy for the peak performance models were 10.5% (SEE = 4.63 mL⋅kg-1⋅min-1) and 11.5% (SEE = 4.11 mL⋅kg-1⋅min-1) for men and women, respectively, with 75% and 72% of the variance explained. For the submaximal performance models accuracy were 14.1% (SEE = 6.24 mL⋅kg-1⋅min-1) and 14.4% (SEE = 5.17 mL⋅kg-1⋅min-1) for men and women, respectively, with 55% and 56% of the variance explained. The validation and cross-validation samples displayed SEE and variance explained in agreement with the total sample. Cross-classification between measured and predicted VO2peak accurately classified 91% of the participants within the correct or nearest quintile of measured VO2peak. Conclusion Judicious use of the exercise prediction models presented in this study offers valuable information in providing a fairly accurate assessment of VO2peak, which may be beneficial for risk stratification in health care settings

A review of the factual basis of interactions between farmed and wild salmon as it applies to salmon lice

The report entails a critical review of the factual basis(*) concerning interactions between farmed and wild salmonids as it applies to salmon lice, with specific relevance to Norway. The summary is in accordance with the report roughly divided into three main areas: i) Population dynamics; various factors that affect stocks of wild (anadromous) salmonids ii) Evaluation of the current knowledge concerning salmon lice; about occurrence of salmon lice, vectors and dispersion models iii) Evaluation of the current knowledge concerning status reporting that forms the basis for decision makers / the management of wild salmonid stocks. *This report is a translation of the report published in Norwegian in April 2011. Hence, studies performed and published after April 2011 are not included in this review.A review of the factual basis of interactions between farmed and wild salmon as it applies to salmon licepublishedVersio

Age-related decline in peak oxygen uptake: Cross-sectional vs. longitudinal findings. A review

Cardiorespiratory fitness is established as an important prognostic factor for cardiovascular and general health. In clinical settings cardiorespiratory fitness is often measured by cardiopulmonary exercise testing determining the gold-standard peak oxygen uptake (VO2peak). Due to the considerable impact of age and sex on VO2peak, results from cardiopulmonary exercise testing are typically assessed in the context of age- and sex-specific reference values, and multiple studies have been conducted establishing reference materials by age and sex using cross-sectional designs. However, crossectional and longitudinal studies have shown somewhat conflicting results regarding age-related declines of VO2peak, with larger declines reported in longitudinal studies. In this brief review, we compare findings from crossectional and longitudinal studies on age-related trajectories in VO2peak to highlight differences in these estimates which should be acknowledged when clinicians interpret VO2peak measurements repeated over time

Non-Smoking tobacco affects endothelial function in healthy men in one of the largest health studies ever performed; the nord-trøndelag health study in Norway; HUNT3

Background Oral tobacco (snuff) is taking a large market share in Scandinavia, especially with young users. However, long-term health effects are unknown. Small studies show association between snuff and reduced endothelial function, representing an early stage of vascular injury that often precedes manifest cardiovascular disease by several years. We therefore determined the associations between snuff and endothelial function in a large sample of healthy Norwegian men. Methods and Design In the Fitness substudy of the Nord-Trøndelag Health Study (HUNT3), endothelial function was measured by flow-mediated dilation (FMD). Aerobic fitness was measured by peak oxygen uptake (VO2peak). A cross-sectional design including 1 592 self-reported healthy men compared these observations with records of present tobacco use, standard cardiovascular risk factors, and socioeconomic status, using general linear models. Results FMD was lower in snuff users (FMD: 4.12%, 3.63, 4.61) compared to non-users (FMD: 4.52%, 4.27, 4.78) after adjustment for age (difference: -0.57%, -1.12, -0.01). After further adjustment for potential confounders, FMD still tended to be lower in snuff users than in non-users (difference: -0.53%, -1.09, 0.02). This difference was even more pronounced in the inactive snuff users (-0.83%, -1.59, -0.06) and in the low fit snuff users (-0.74%, CI -0.55, 0.079). Conclusions Oral tobacco is associated with a tendency towards reduced endothelial function, indicating vascular changes that precede cardiovascular disease. The strongest associations were found in men with low physical activity or reduced aerobic fitness

Non-Smoking Tobacco Affects Endothelial Function in Healthy Men in One of the Largest Health Studies Ever Performed; The Nord-Trøndelag Health Study in Norway; HUNT3.

Oral tobacco (snuff) is taking a large market share in Scandinavia, especially with young users. However, long-term health effects are unknown. Small studies show association between snuff and reduced endothelial function, representing an early stage of vascular injury that often precedes manifest cardiovascular disease by several years. We therefore determined the associations between snuff and endothelial function in a large sample of healthy Norwegian men.In the Fitness substudy of the Nord-Trøndelag Health Study (HUNT3), endothelial function was measured by flow-mediated dilation (FMD). Aerobic fitness was measured by peak oxygen uptake (VO2peak). A cross-sectional design including 1 592 self-reported healthy men compared these observations with records of present tobacco use, standard cardiovascular risk factors, and socioeconomic status, using general linear models.FMD was lower in snuff users (FMD: 4.12%, 3.63, 4.61) compared to non-users (FMD: 4.52%, 4.27, 4.78) after adjustment for age (difference: -0.57%, -1.12, -0.01). After further adjustment for potential confounders, FMD still tended to be lower in snuff users than in non-users (difference: -0.53%, -1.09, 0.02). This difference was even more pronounced in the inactive snuff users (-0.83%, -1.59, -0.06) and in the low fit snuff users (-0.74%, CI -0.55, 0.079).Oral tobacco is associated with a tendency towards reduced endothelial function, indicating vascular changes that precede cardiovascular disease. The strongest associations were found in men with low physical activity or reduced aerobic fitness

Correlation plots between measured and predicted VO_2peak with 95% prediction bands from peak treadmill performance (A and B), and submaximal treadmill performance (C and D).

<p>Correlation plots between measured and predicted VO_2peak with 95% prediction bands from peak treadmill performance (A and B), and submaximal treadmill performance (C and D).</p

A simple nonexercise model of cardiorespiratory fitness predicts long-term mortality

Purpose: Cardiorespiratory fitness (CRF) is a strong predictor of future health, but measurements of CRF are time consuming and involve costly test procedures. We assessed whether a simple, non-exercise-based test of CRF predicted long-term all-cause and cardiovascular disease (CVD) mortality. Methods: In this prospective cohort study, we used a previously published nonexercise test to estimate CRF in healthy men (n = 18,348) and women (n = 18,764) from the first HUNT study (1984-1986) in Norway. We used Cox regression to obtain HR for mortality during a mean follow-up of 24 yr. Assessment of model validity was performed by standard procedures of discrimination and calibration. Results: CRF was inversely associated with all-cause and CVD mortality in men and women below 60 yr of age at baseline, after adjustment for confounders. For each MET-higher CRF (MET, approximately 3.5 mL.kg(-1.)min(-1)), HR for CVD mortality was 21% lower in both men (95% confidence interval (CI), 17%-26%) and women (95% CI, 12%-29%). HR for all-cause mortality was 15% (95% CI, 12%-17%) lower in men and 8% (95% CI, 3%-3%) lower in women for each MET-higher CRF. The ability of the model to discriminate mortality risk among participants below 60 yr was better for CRF (area under the curve (AUC), 0.70-0.77) compared with that for each variable that constituted the model (AUC, 0.55-0.63) and an aggregated sum of z-scores for each variable (AUC, 0.61-0.65). Comparison of observed and predicted risk indicated good model calibration. Conclusions: This method of assessing CRF is feasible and practically useful in primary care for identification of apparently healthy individuals at increased risk of premature CVD disease and all-cause mortality