Leisure-time physical activity and type 2 diabetes during a 28 year follow-up in twins

Does engagement in frequent physical activity improve diabetes mellitus among older adults in India? A propensity score matching approach

BACKGROUND AND AIMS

Diabetes is a major chronic condition and was identified as one of the four priority non-communicable diseases that the United Nations targeted because of its increasing disease burden. The present study aims to examine the impact of physical activity on improving diabetes mellitus among older adults in India.

METHODS

This study utilizes data from India's first nationally representative longitudinal ageing survey (2017-18). Descriptive along with bivariate analysis was used to present the preliminary results. Additionally, Propensity score matching (PSM) analysis was used.

RESULTS

About 14% of older adults suffered from diabetes. Eighteen percent of older adults did frequent physical activity. The estimated average treatment effect on the treated (ATT) values in treated and control groups were 0.123 and 0.147, respectively, indicating that the prevalence of diabetes among older adults was reduced by 2.5% points because of frequent physical activity. The average treatment effect on the untreated (ATU) results indicates that among older adults who did not do frequent physical activity, if they did frequent physical activity, the prevalence of diabetes is likely to decrease by 2.2% points.

CONCLUSION

Our findings show that frequent physical activity is associated with a lower risk of diabetes in older adults. The results underscore the need to develop strategies of promoting an active lifestyle by maintaining physical activity to combat the diabetes epidemic in the older population.

Effect of Caloric Restriction on Aging: Fixing the Problems of Nutrient Sensing in Postmitotic Cells?

The review discusses the role of metabolic disorders (in particular, insulin resistance) in the development of age-related diseases and normal aging with special emphasis on the changes in postmitotic cells of higher organisms. Caloric restriction helps to prevent such metabolic disorders, which could probably explain its ability to prolong the lifespan of laboratory animals. Maintaining metabolic homeostasis is especially important for the highly differentiated long-lived body cells, whose lifespan is comparable to the lifespan of the organism itself. Normal functioning of these cells can be ensured only upon correct functioning of the cytoplasm clean-up system and availability of all required nutrients and energy sources. One of the central problems in gerontology is the age-related disruption of glucose metabolism leading to obesity, diabetes, metabolic syndrome, and other related pathologies. Along with the adipose tissue, skeletal muscles are the main consumers of insulin; hence the physical activity of muscles, which supports their energy metabolism, delays the onset of insulin resistance. Insulin resistance disrupts the metabolism of cardiomyocytes, so that they fail to utilize the nutrients to perform their functions even being surrounded by a nutrient-rich environment, which contributes to the development of age-related cardiovascular diseases. Metabolic pathologies also alter the nutrient sensitivity of neurons, thus disrupting the action of insulin in the central nervous system. In addition, there is evidence that neurons can develop insulin resistance as well. It has been suggested that affecting nutritional sensors (e.g., AMPK) in postmitotic cells might improve the state of the entire multicellular organism, slow down its aging, and increase the lifespan.

Systemic cross-talk between brain, gut, and peripheral tissues in glucose homeostasis: effects of exercise training (CROSSYS). Exercise training intervention in monozygotic twins discordant for body weight

BACKGROUND

Obesity and physical inactivity are major global public health concerns, both of which increase the risk of insulin resistance and type 2 diabetes. Regulation of glucose homeostasis involves cross-talk between the central nervous system, peripheral tissues, and gut microbiota, and is affected by genetics. Systemic cross-talk between brain, gut, and peripheral tissues in glucose homeostasis: effects of exercise training (CROSSYS) aims to gain new systems-level understanding of the central metabolism in human body, and how exercise training affects this cross-talk.

METHODS

CROSSYS is an exercise training intervention, in which participants are monozygotic twins from pairs discordant for body mass index (BMI) and within a pair at least the other is overweight. Twins are recruited from three population-based longitudinal Finnish twin studies, including twins born in 1983-1987, 1975-1979, and 1945-1958. The participants undergo 6-month-long exercise intervention period, exercising four times a week (including endurance, strength, and high-intensity training). Before and after the exercise intervention, comprehensive measurements are performed in Turku PET Centre, Turku, Finland. The measurements include: two positron emission tomography studies (insulin-stimulated whole-body and tissue-specific glucose uptake and neuroinflammation), magnetic resonance imaging (brain morphology and function, quantification of body fat masses and organ volumes), magnetic resonance spectroscopy (quantification of fat within heart, pancreas, liver and tibialis anterior muscle), echocardiography, skeletal muscle and adipose tissue biopsies, a neuropsychological test battery as well as biosamples from blood, urine and stool. The participants also perform a maximal exercise capacity test and tests of muscular strength.

DISCUSSION

This study addresses the major public health problems related to modern lifestyle, obesity, and physical inactivity. An eminent strength of this project is the possibility to study monozygotic twin pairs that share the genome at the sequence level but are discordant for BMI that is a risk factor for metabolic impairments such as insulin resistance. Thus, this exercise training intervention elucidates the effects of obesity on metabolism and whether regular exercise training is able to reverse obesity-related impairments in metabolism in the absence of the confounding effects of genetic factors.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT03730610 . Prospectively registered 5 November 2018.

Responses to oral glucose challenge differ by physical activity volume and intensity: A pilot study

BACKGROUND

One-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.

METHODS

Thirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m²; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.

RESULTS

There were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).

CONCLUSION

The results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.

Twin studies on the association of physical activity with cognitive and cerebral outcomes

Regular physical activity (PA) offers positive effects on the human body. However, the effects of PA on cognition and in the brain are less clear. In this paper, we narratively review the relationship of PA with cognition and dementia, first from general perspective and then through genetically informed studies on the topic. Then we move on to imaging studies on exercise and brain anatomy first by presenting an overall picture of the topic and then discussing brain imaging studies addressing PA and brain structure in twins in more detailed way. Regarding PA and cognition or dementia, genetically informed studies are uncommon, even though the relationship between PA and cognitive ageing has been extensively studied. It is challenging to find twin pairs discordant for PA and dementia. Concerning brain imaging studies, among PA discordant young adult twin pairs, the more active co-twins showed larger gray matter volumes in striatal, prefrontal, and hippocampal regions and in electrophysiological studies automatic deviance-detection processes differed in brain regions involved with sensorimotor, visual and memory functions.

Different domains of self-reported physical activity and risk of type 2 diabetes in a population-based Swedish cohort: the Malmö diet and Cancer study

BACKGROUND

While a dose-response relationship between physical activity and risk of diabetes has been demonstrated, few studies have assessed the relative importance of different measures of physical activity on diabetes risk. The aim was to examine the association between different self-reported measures of physical activity and risk of type 2 diabetes in a prospective cohort study.

METHODS

Out of 26,615 adults (45-74 years, 60% women) in the population-based Swedish Malmö Diet and Cancer Study cohort, 3791 type 2 diabetes cases were identified from registers during 17 years of follow-up. Leisure-time (17 activities), occupational and domestic physical activity were assessed through a questionnaire, and these and total physical activity were investigated in relation to type 2 diabetes risk.

RESULTS

All physical activity measures showed weak to modest associations with type 2 diabetes risk. The strongest association was found in the lower end of leisure-time physical activity in dose-response analysis at levels approximately below 22 MET-hrs/week (300 min/week) representing around 40% of the population. Compared with the lowest quintile, the moderate leisure-time physical activity category had a 28% (95% CI: 0.71, 0.87) decreased risk of type 2 diabetes. Total physical activity showed a similar, but weaker, association with diabetes risk as to that of leisure-time physical activity. Domestic physical activity was positively and linearly related to diabetes risk, HR = 1.11 (95% CI: 0.99, 1.25) comparing highest to lowest quintile. There was no association between occupational physical activity and diabetes risk.

CONCLUSION

A curvilinear association was observed between leisure-time physical activity and risk of diabetes. Beyond a threshold level of approximately 22 MET-hrs/week or 300 min/week, no additional risk reduction was observed with increase in physical activity.

The Older Finnish Twin Cohort - 45 Years of Follow-up

The older Finnish Twin Cohort (FTC) was established in 1974. The baseline survey was in 1975, with two follow-up health surveys in 1981 and 1990. The fourth wave of assessments was done in three parts, with a questionnaire study of twins born during 1945-1957 in 2011-2012, while older twins were interviewed and screened for dementia in two time periods, between 1999 and 2007 for twins born before 1938 and between 2013 and 2017 for twins born in 1938-1944. The content of these wave 4 assessments is described and some initial results are described. In addition, we have invited twin-pairs, based on response to the cohortwide surveys, to participate in detailed in-person studies; these are described briefly together with key results. We also review other projects based on the older FTC and provide information on the biobanking of biosamples and related phenotypes.

Protective role of physical activity on type 2 diabetes: Analysis of effect modification by race-ethnicity

BACKGROUND

It is well known physical activity (PA) plays a role in the prevention of type 2 diabetes (T2D). However, the extent to which PA may affect T2D risk among different race-ethnic groups is unknown. Therefore, the aim of the present study was to systematically examine the effect modification of race-ethnicity on PA and T2D.

METHODS

The PubMed and Embase databases were systematically searched through June 2016. Study assessment for inclusion was conducted in three phases: title review (n = 13 022), abstract review (n = 2200), and full text review (n = 265). In all, 27 studies met the inclusion criteria and were used in the analysis. Relative risks (RRs) and 95% confidence intervals (CIs) were extracted and analyzed using Comprehensive Meta-Analysis software. All analyses used a random-effects model.

RESULTS

A significant protective summary RR, comparing the most active group with the least active PA group, was found for non-Hispanic White (RR 0.71, 95% CI 0.60-0.85), Asians (RR 0.76, 95% CI 0.67-0.85), Hispanics (RR 0.75, 95% CI 0.64-0.89), and American Indians (RR 0.73, 95% CI 0.60-0.88). The summary effect for non-Hispanic Blacks (RR 0.91, 95% CI 0.76-1.08) was not significant.

CONCLUSIONS

The results of the present study indicate that PA (comparing most to least active groups) provides significant protection from T2D, with the exception of non-Hispanic Blacks. The results also indicate a need for race-ethnicity-specific reporting of RRs in prospective cohort studies that incorporate multiethnic samples.

Lifestyle precision medicine: the next generation in type 2 diabetes prevention?

The driving force behind the current global type 2 diabetes epidemic is insulin resistance in overweight and obese individuals. Dietary factors, physical inactivity, and sedentary behaviors are the major modifiable risk factors for obesity. Nevertheless, many overweight/obese people do not develop diabetes and lifestyle interventions focused on weight loss and diabetes prevention are often ineffective. Traditionally, chronically elevated blood glucose concentrations have been the hallmark of diabetes; however, many individuals will either remain 'prediabetic' or regress to normoglycemia. Thus, there is a growing need for innovative strategies to tackle diabetes at scale. The emergence of biomarker technologies has allowed more targeted therapeutic strategies for diabetes prevention (precision medicine), though largely confined to pharmacotherapy. Unlike most drugs, lifestyle interventions often have systemic health-enhancing effects. Thus, the pursuance of lifestyle precision medicine in diabetes seems rational. Herein, we review the literature on lifestyle interventions and diabetes prevention, describing the biological systems that can be characterized at scale in human populations, linking them to lifestyle in diabetes, and consider some of the challenges impeding the clinical translation of lifestyle precision medicine.

Childhood Socioeconomic Disadvantage, Occupational, Leisure-Time, and Household Physical Activity, and Diabetes in Adulthood

BACKGROUND

Regular physical activity is a key way to prevent disease. However, we have a limited understanding of the socioeconomic precursors and glucoregulatory sequelae of engaging in physical activity in different domains.

METHODS

We examined the associations among life course socioeconomic disadvantage; meeting the physical activity guidelines with leisure-time physical activity, occupational physical activity, or household physical activity; and prediabetes and diabetes in the Midlife in the United States national study (N = 986).

RESULTS

Childhood disadvantage was associated with lower odds of meeting the guidelines with leisure-time physical activity (odds ratio = 0.75; 95% confidence interval, 0.65-0.86). Adulthood disadvantage was associated with higher odds of meeting the guidelines with occupational physical activity (odds ratio = 1.94; 95% confidence interval, 1.49-2.53). Importantly, while meeting the guidelines with leisure-time physical activity was associated with lower odds of prediabetes and diabetes, we found no evidence for associations among occupational physical activity, household physical activity, and glucoregulation.

CONCLUSION

Current US physical activity guidelines do not differentiate between physical activity for leisure or work, assuming that physical activity in any domain confers comparable health benefits. We documented important differences in the associations among lifetime socioeconomic disadvantage, physical activity domain, and diabetes, suggesting that physical activity domain potentially belongs in the guidelines, similar to other characteristics of activity (eg, type, intensity).

Association between Meeting Physical Activity Guidelines and Mortality in Korean Adults: An 8-year Prospective Study

PURPOSE

Although previous studies have investigated the association between physical activity and various health outcomes, limited information is available on the effect of meeting new governmental guidelines for physical activity on the risk of mortality in Korean adults. This study aimed to examine the prospective association between meeting these guidelines and all-cause mortality during an 8-year follow-up using a large nationwide sample of middle-aged and older adults in Korea.

METHODS

This prospective study was conducted based on the Korean Longitudinal Study of Ageing. The study participants included 9,177 adults aged 45 years or older at baseline, and all participants were monitored in a 2-year cycle during an 8-year period (70,873 person-years). The risk of mortality was analyzed by determining physical activity levels using the Cox proportional hazard models, and the hazard ratio (HR) and 95% confidence interval (CI) were estimated using Cox models.

RESULTS

A statistically significant effect of physical activity on the reduced risk of mortality was observed in cases in which the participants met the guidelines compared to the inactive group (HR: 0.68, 95% CI: 0.58-0.81 vs. the inactive group). A strong association between meeting the recommended physical activity levels and the reduced risk of mortality was also found for non-smokers (HR: 0.62; 95% CI: 0.51-0.76 vs. the inactive group), but not for current smokers (HR: 0.93; 95% CI: 0.67-1.29 vs. the inactive group).

CONCLUSION

Meeting physical activity guidelines was associated with a decreased risk of all-cause mortality for Korean adults. Our results also suggest that smoking reduces the protective effect of physical activity on the risk of mortality.

Targeting vascular (endothelial) dysfunction

Cardiovascular diseases are major contributors to global deaths and disability-adjusted life years, with hypertension a significant risk factor for all causes of death. The endothelium that lines the inner wall of the vasculature regulates essential haemostatic functions, such as vascular tone, circulation of blood cells, inflammation and platelet activity. Endothelial dysfunction is an early predictor of atherosclerosis and future cardiovascular events. We review the prognostic value of obtaining measurements of endothelial function, the clinical techniques for its determination, the mechanisms leading to endothelial dysfunction and the therapeutic treatment of endothelial dysfunction. Since vascular oxidative stress and inflammation are major determinants of endothelial function, we have also addressed current antioxidant and anti-inflammatory therapies. In the light of recent data that dispute the prognostic value of endothelial function in healthy human cohorts, we also discuss alternative diagnostic parameters such as vascular stiffness index and intima/media thickness ratio. We also suggest that assessing vascular function, including that of smooth muscle and even perivascular adipose tissue, may be an appropriate parameter for clinical investigations.

LINKED ARTICLES

This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.

Leisure-time, occupational, household physical activity and insulin resistance (HOMAIR) in the Midlife in the United States (MIDUS) national study of adults

Physical activity is a critical cornerstone of successful diabetes prevention and management. Current U.S. physical activity guidelines do not differentiate among physical activity for leisure, work, or other purposes, effectively implying that physical activity in any domain confers the same health benefits. It is currently unknown whether physical activity performed in different domains (leisure-time physical activity = LTPA, occupational physical activity = OPA, and household physical activity = HPA) is associated with insulin resistance. The associations between LTPA, OPA, HPA, and insulin resistance (indexed by homeostatic model assessment of insulin resistance = HOMAIR) were determined in the MIDUS (Midlife in the U.S.; 1995-2006) national study (N = 1229, ages 34-84). Not meeting physical activity guidelines with LTPA was associated with a 34% higher HOMAIR among participants with diabetes, 42% higher HOMAIR among participants with prediabetes, and 17% higher HOMAIR among participants with normal glucoregulation. These associations were slightly attenuated but remained significant after further adjusting for obesity status, education, smoking, and alcohol intake. There was no evidence that engaging in OPA or HPA was significantly associated with HOMAIR. These results confirm the health-promoting role of LTPA and suggest that LTPA may provide unique glucoregulatory benefits, as opposed to HPA and OPA. Physical activity domain is an important dimension that potentially belongs in the guidelines, similarly to intensity, frequency, duration, and type.

Persistent leisure-time physical activity in adulthood and use of antidepressants: A follow-up study among twins

BACKGROUND

To study whether persistent leisure-time physical activity (PA) during adulthood predicts use of antidepressants later in life.

METHODS

The Finnish Twin Cohort comprises same-sex twin pairs born before 1958, of whom 11 325 individuals answered PA questions in 1975, 1981 and 1990 at a mean age of 44 years (range 33-60). PA volume over 15-years was used as the predictor of subsequent use of antidepressants. Antidepressant use (measured as number of purchases) for 1995-2004 were collected from the Finnish Social Insurance Institution (KELA) prescription register. Conditional logistic regression was conducted to calculate odds ratios (OR) with 95% confidence intervals (CI) for the use of antidepressants in pairs discordant for PA (642, including 164 monozygotic (MZ) pairs).

RESULTS

Altogether 229 persons had used at least one prescribed antidepressant during the study period. Active co-twins had a lower risk (unadjusted OR 0.80, 95%CI 0.67-0.95) for using any amount of antidepressants than their inactive co-twins; trends being similar for DZ (0.80, 0.67-0.97) and MZ pairs (0.78, 0.51-1.17). The lowest odds ratio (0.51, 0.26-0.98) was seen among MZ pairs after adjusting for BMI, smoking and binge drinking. The point estimates were similar but non-significant for long-term antidepressant use (4+purchases equivalent to 12 months use).

LIMITATIONS

Self-reported physical activity and low number of discordant MZ pairs.

DISCUSSION

Use of antidepressants was less common among physically active co-twins even when shared childhood experiences and genetic background were controlled for. Physical activity in midlife may therefore be important in preventing mild depression later in life.

Leisure-time physical activity and risk of type 2 diabetes: a meta-analysis of prospective cohort studies

Published articles reported controversial results about the association between leisure-time physical activity (LTPA) and risk of type 2 diabetes. A meta-analysis of prospective cohort studies was conducted to explore the effect of LTPA on the incidence of type 2 diabetes. PubMed and Embase databases were searched from its inception to June 13, 2014. Fixed or random effects models were used to calculate the pooled effect sizes based on between-study heterogeneity that was examined by the Q test and I (2) statistic. A total of eight studies, including 296,395 participants and 10,815 incident cases, were included in this study. Both high-level LTPA [high vs. low: hazard ratio (HR) 0.69, 95 % confidence interval (CI) 0.61-0.78] and moderate-level LTPA (moderate vs. low: HR 0.79, 95 % CI 0.70-0.89) were associated with decreased incidence of type 2 diabetes. In conclusion, LTPA was significantly associated with decreased risk of diabetes; high-level LTPA is more beneficial in decreasing the incidence of type 2 diabetes than moderate-level LTPA.

Cut-off values for step count and TV viewing time as discriminators of hyperglycaemia in Brazilian children and adolescents

BACKGROUND

The use of step count and TV viewing time to discriminate youngsters with hyperglycaemia is still a matter of debate.

AIM

To establish cut-off values for step count and TV viewing time in children and adolescents using glycaemia as the reference criterion.

SUBJECTS AND METHODS

A cross-sectional study was conducted on 1044 schoolchildren aged 6-18 years from Northeastern Brazil. Daily step counts were assessed with a pedometer over 1 week and TV viewing time by self-report.

RESULTS

The area under the curve (AUC) ranged from 0.52-0.61 for step count and from 0.49-0.65 for TV viewing time. The daily step count with the highest discriminatory power for hyperglycaemia was 13 884 (sensitivity = 77.8; specificity = 51.8) for male children and 12 371 (sensitivity = 55.6; specificity = 55.5) and 11 292 (sensitivity = 57.7; specificity = 48.6) for female children and adolescents respectively. The cut-off for TV viewing time with the highest discriminatory capacity for hyperglycaemia was 3 hours/day (sensitivity = 57.7-77.8; specificity = 48.6-53.2).

CONCLUSION

This study represents the first step for the development of criteria based on cardiometabolic risk factors for step count and TV viewing time in youngsters. However, the present cut-off values have limited practical application because of their poor accuracy and low sensitivity and specificity.

Physical activity level and incident type 2 diabetes among Chinese adults

PURPOSE

The objective is to examine the association between physical activity level (PAL) and incident type 2 diabetes among middle-age and older Chinese men and women in urban China.

METHODS

This prospective study included 6348 participants (age 35 to 74 yr) who were free of diabetes and cardiovascular disease at baseline. PAL was estimated on the basis of self-reported overall physical activity on a typical day. According to PAL, participants were classified into four groups: sedentary (PAL, 1.00-1.39), low active (PAL, 1.40-1.59), active (PAL, 1.60-1.89), and very active (PAL, >1.89). The association of PAL with incident diabetes was examined by Cox proportional hazards model.

RESULTS

During 7.9 yr of follow-up (50,293 person-years), 478 incident cases of type 2 diabetes were identified. After adjustment for age, sex, geographic region, educational level, smoking, alcohol use, and family history of diabetes, the HR (95% CI) values for type 2 diabetes across increasing categories of PAL were 1.00 (reference), 0.82 (0.62-1.09), 0.63 (0.47-0.83), and 0.47 (0.36-0.61), respectively (P for trend <0.0001). Additional adjustment for baseline body mass index or waist circumference attenuated the magnitude of risk reduction, but it remained significant. The inverse association between PAL and risk of incident diabetes was persistent in subgroup analyses according to age, sex, hypertension, smoking, body mass index, waist circumference, and fasting plasma glucose level.

CONCLUSIONS

Higher PAL is associated with substantial reduction in risk of type 2 diabetes. Our findings suggest the importance of a physically active lifestyle in the prevention of diabetes.

Physical activity, fitness, glucose homeostasis, and brain morphology in twins

PURPOSE

The main aim of the present study (FITFATTWIN) was to investigate how physical activity level is associated with body composition, glucose homeostasis, and brain morphology in young adult male monozygotic twin pairs discordant for physical activity.

METHODS

From a population-based twin cohort, we systematically selected 10 young adult male monozygotic twin pairs (age range, 32-36 yr) discordant for leisure time physical activity during the past 3 yr. On the basis of interviews, we calculated a mean sum index for leisure time and commuting activity during the past 3 yr (3-yr LTMET index expressed as MET-hours per day). We conducted extensive measurements on body composition (including fat percentage measured by dual-energy x-ray absorptiometry), glucose homeostasis including homeostatic model assessment index and insulin sensitivity index (Matsuda index, calculated from glucose and insulin values from an oral glucose tolerance test), and whole brain magnetic resonance imaging for regional volumetric analyses.

RESULTS

According to pairwise analysis, the active twins had lower body fat percentage (P = 0.029) and homeostatic model assessment index (P = 0.031) and higher Matsuda index (P = 0.021) compared with their inactive co-twins. Striatal and prefrontal cortex (subgyral and inferior frontal gyrus) brain gray matter volumes were larger in the nondominant hemisphere in active twins compared with those in inactive co-twins, with a statistical threshold of P < 0.001.

CONCLUSIONS

Among healthy adult male twins in their mid-30s, a greater level of physical activity is associated with improved glucose homeostasis and modulation of striatum and prefrontal cortex gray matter volume, independent of genetic background. The findings may contribute to later reduced risk of type 2 diabetes and mobility limitations.

Association of Change of Anthropometric Measurements With Incident Type 2 Diabetes Mellitus: A Pooled Analysis of the Prospective Population-Based CARLA and SHIP Cohort Studies

Our objective was to investigate the association of change of anthropometric measurements and the incidence of type 2 diabetes mellitus (T2DM) within a pooled sample of 2 population-based cohorts.A final sample of 1324 women and 1278 men aged 31 to 83 years from 2 prospective cohorts in Germany, the CARLA (Cardiovascular Disease - Living and Ageing in Halle) and the SHIP study (Study of Health in Pomerania), were pooled. The association of change of body weight and waist circumference (WC) with incidence of T2DM was assessed by calculating sex-specific hazard ratios (HRs). We investigated the absolute change of markers of obesity as well as change relative to the baseline value and estimated crude and adjusted HRs. Furthermore, we conducted the analyses stratified by obesity status and age (<60 vs ≥60 years) at baseline.Associations were found for both change of body weight and WC and incidence of T2DM in the crude and adjusted analyses. In the stratified study sample, those participants with a body mass index of <30 kg/m at baseline showed considerably lower HRs compared with obese women and men for both weight and WC. In the age-stratified analysis, we still found associations between change of weight and WC and incident T2DM with only marginal differences between the age groups.Our study showed associations of change of weight and WC as markers of obesity with incidence of T2DM. Keeping a healthy and primarily stable weight should be the goal for preventing the development of T2DM.

Physical activity and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis

We investigated the association between specific types of physical activity and the risk of type 2 diabetes in a systematic review and meta-analysis of published studies. PubMed, Embase and Ovid databases were searched for prospective studies and randomized trials up to 2nd of March 2015. Summary relative risks (RRs) were calculated using a random effects model. Eighty-one studies were included. The summary RRs for high versus low activity were 0.65 (95 % CI 0.59-0.71, I(2) = 18 %, n = 14) for total physical activity, 0.74 (95 % CI 0.70-0.79, I(2) = 84 %, n = 55) for leisure-time activity, 0.61 (95 % CI 0.51-0.74, I(2) = 73 %, n = 8) for vigorous activity, 0.68 (95 % CI 0.52-0.90, I(2) = 93 %, n = 5) for moderate activity, 0.66 (95 % CI 0.47-0.94, I(2) = 47 %, n = 4) for low intensity activity, and 0.85 (95 % CI 0.79-0.91, I(2) = 0 %, n = 7) for walking. Inverse associations were also observed for increasing activity over time, resistance exercise, occupational activity and for cardiorespiratory fitness. Nonlinear relations were observed for leisure-time activity, vigorous activity, walking and resistance exercise (p nonlinearity < 0.0001 for all), with steeper reductions in type 2 diabetes risk at low activity levels than high activity levels. This meta-analysis provides strong evidence for an inverse association between physical activity and risk of type 2 diabetes, which may partly be mediated by reduced adiposity. All subtypes of physical activity appear to be beneficial. Reductions in risk are observed up to 5-7 h of leisure-time, vigorous or low intensity physical activity per week, but further reductions cannot be excluded beyond this range.

Health-Related Findings Among Twin Pairs Discordant for Leisure-Time Physical Activity for 32 Years: The TWINACTIVE Study Synopsis

We are lacking very long-term and controlled intervention studies investigating the effects of habitual physical activity on health-related factors. To address this gap, we performed a natural experiment by identifying same-sex twin pairs in which the co-twins of each pair differed with respect to leisure-time physical-activity habits throughout their adult life. Our criterion for the discordance was that the same co-twin had a higher leisure time-activity volume than that of the other member of the pair at the majority –– if not all –– of the follow-up time points according to reported/interviewed physical-activity data. Overall, we identified and conducted multidimensional health-related measurements (including fitness, body composition, cardiometabolic risk factor levels, bone and arterial status, and exercise motivation) of 16 twin pairs (seven monozygotic (MZ) and nine dizygotic (DZ) pairs, mean age 60 years) who had persistent discordance in leisure-time physical-activity habits over three decades (TWINACTIVE study). In our discordant-pair study design, after adjusting for sequence-level genes, both systemic-level metabolic, and site-specific structural findings differed significantly in the pairwise analysis in MZ pairs only. These findings included intrapair differences in accumulated fat depots and structure of heart, arteries, and bones. In addition, our study revealed intrapair differences in metabolic and regulatory pathways, which may partly explain the mechanistic links between long-term physical activity, phenotypic changes, and decreased risk of cardiometabolic diseases.

Physical activity and dementia: long-term follow-up study of adult twins

INTRODUCTION

Physical activity is associated with a decreased occurrence of dementia. In twins, we investigated the effect of persistent physical activity in adulthood on mortality due to dementia.

MATERIALS AND METHODS

Physical activity was queried in 1975 and 1981 from the members of the older Finnish Twin Cohort (n = 21,791), who were aged 24-60 years at the end of 1981. The subjects were divided into three categories according to the persistence of their vigorous physical activity. Dementia deaths were followed up to the end of 2011.

RESULTS

During the 29-year follow-up, 353 subjects died of dementia. In individual-based analyses the age- and sex-adjusted hazard ratio (HR) was 0.65 (95% CI 0.43-0.98) for subjects partaking in vigorous physical activities in both 1975 and 1981 compared to those who were inactive in both years. No significant change was observed after adjusting for potential confounding factors. The corresponding HR for within-pair comparisons of the less active twin versus the more active co-twin was 0.48 (95% CI 0.17-1.32). The results for analyses of the volume of physical activity were inconclusive.

CONCLUSIONS

Persistent vigorous leisure-time physical activity protects from dementia, and the effect appears to remain after taking into account childhood environment.

Objectively measured physical activity in Finnish employees: a cross-sectional study

OBJECTIVES

To objectively measure the amount of intensity-specific physical activity by gender and age with respect to body mass index (BMI) during workdays and days off among Finnish employees.

DESIGN

A cross-sectional study.

SETTING

Primary care occupational healthcare units.

PARTICIPANTS

A sample of 9554 Finnish employees (4221 men and 5333 women; age range 18-65 years; BMI range 18.5-40 kg/m(2)) who participated in health assessments related to occupational health promotion.

MAIN OUTCOME MEASUREMENTS

The amount of moderate-to-vigorous (MVPA) and vigorous (VPA) physical activity (≥3 and ≥6 metabolic equivalents, respectively) was assessed by estimating the minute-to-minute oxygen consumption from the recorded beat-to-beat R-R interval data. The estimation method used heart rate, respiration rate and on/off response information from R-R interval data calibrated by age, gender, height, weight and self-reported physical activity class. The proportion of participants fulfilling the aerobic physical activity recommendation of ≥150 min/week was calculated on the basis of ≥10 min bouts, by multiplying the VPA minutes by 2.

RESULTS

Both MVPA and VPA were higher among men and during days off, and decreased with increasing age and BMI (p<0.001 for all). Similar results were observed when the probability of having a bout of MVPA or VPA lasting continuously for ≥10 min per measurement day was studied. The total amount of VPA was low among overweight (mean ≤2.6 min/day), obese (mean ≤0.6 min/day) and all women in the age group 51-65 years (mean ≤2.5 min/day) during both types of days. The proportion of participants fulfilling the aerobic physical activity recommendation was highest for normal weight men (65%; 95% CI 62% to 67%) and lowest for obese women (10%; 95% CI 8% to 12%).

CONCLUSIONS

Objectively measured physical activity is higher among men and during days off, and decreases with increasing age and BMI. The amount of VPA is very low among obese, overweight and older women.

Perceived sufficiency of physical activity levels among adults at high risk of type 2 diabetes: the FIN-D2D study

BACKGROUND

Any increase from a low level of physical activity reduces the risk of type 2 diabetes. However, lack of awareness of one's physical activity level insufficiency may act as an obstacle to increased physical activity.

PURPOSE

This study assessed the determinants of perceived physical activity levels (PALs) among adults at high risk of diabetes and the associations with self-reported physical activity.

METHODS

In total, 10,149 adults participated in the FIN-D2D lifestyle intervention at baseline. Opportunistic screening was used in identifying high-risk individuals. Physical activity and perceived PAL sufficiency were assessed and compared. Key risk factors for diabetes and psychosocial and demographic characteristics were analyzed as determinants using logistic regression.

RESULTS

PAL sufficiency was rated realistically by 73 % of men and 75 % of women. Perception of sufficient PAL was more likely among individuals with a smaller waist circumference, a higher level of perceived fitness, and no exercise intention. In men, a higher age, and in women, a lower education, and a lower occupational status, also increased the likelihood of perceiving PAL as sufficient. Out of all the participants, 65 % of men and 66 % of women were inactive. Among the inactive participants, 20 (men) and 16 % (women) overestimated their PAL sufficiency. In both genders, such overestimation was predicted by dyslipidemia, a lower waist circumference, a higher level of perceived fitness, and no exercise intention; also (among men) by a higher age and a family history of diabetes, and (among women) by a lower occupational status, and a lower BMI.

CONCLUSIONS

In diabetes prevention, it is important to recognize the groups that perceive their PAL as sufficient since they may not see increased PAL as a tool for decreasing their risk of diabetes.

Midlife fitness predicts less burden of chronic disease in later life

OBJECTIVE

To investigate the relationship between midlife fitness in healthy adults and the development of nonfatal chronic conditions (CCs) in older age.

DESIGN

Cohort study.

SETTING

Data on participants were drawn from the Cooper Center Longitudinal Study and linked with US Medicare claims made in the years 1999 through 2009.

PARTICIPANTS

The cohort included 18 670 participants (median age, 49 years; 21% women) who had received a comprehensive clinical examination between 1970 and 2009 at the Cooper Center, were ≥65 years of age and covered by Medicare between 1999 and 2009, and who reported no baseline history of CCs such as cardiovascular disease, diabetes, and cancer. The participants tended to be from upper educational and socioeconomic strata.

ASSESSMENT OF RISK FACTORS

Fitness was assessed by maximal treadmill effort using the modified Balke protocol. The participants' treadmill times were classified into age- and sex-specific quintiles (Q) of fitness (Q1, least fit) and converted into metabolic equivalents (MET). Clinical and anthropometric variables and physical activity were measured.

MAIN OUTCOME MEASURES

The main outcome measure was the association between level of fitness in midlife (ie, at study entry) and the development of chronic conditions (specifically, congestive heart failure, ischemic heart disease, stroke, diabetes mellitus, chronic obstructive pulmonary disease, chronic kidney disease, Alzheimer's disease, and colon or lung cancer), recorded by Medicare. The conditions were each assigned a value of 1, and those present were summed for survivors at ages 70, 75, 80, and 85 years. Death was an additional outcome. Total follow-up was 120 780 person-years.

MAIN RESULTS

At study entry the participants had, overall, low levels of traditional risk factors for CCs, with the less fit having somewhat less healthy risk factor profiles. The highest level of midlife fitness (Q5) was associated with developing fewer CCs compared with low midlife fitness (Q1) in men (15.6; 95% confidence interval [CI], 15.0-16.2 vs 28.2; 95% CI, 27.4-29.0 per 100 person-years) and women (11.4; 95% CI, 10.5-12.3 vs 20.1; 95% CI, 18.7-21.6 per 100 person-years). After multivariate adjustment, higher fitness remained associated with a lower risk of developing CCs (men: hazard ratio [HR], 0.95; 95% CI, 0.94-0.96 per MET; and women: HR, 0.94; 95% CI, 0.91-0.96 per MET). Level of fitness was similarly associated with the development of CCs in younger and older participants. Among the 2406 participants who died during the study period, the number of CCs among the more fit persons was significantly lower than that among the less fit; thus, in their final 5 years of life, 58.3% of fitness Q4 and Q5 versus 43.5% of Q1 had ≤1 CC and 9.5% of Q4 and Q5 versus 18.3% of Q1 had ≥4 CCs.

CONCLUSIONS

Healthy, fit, middle-aged adults developed fewer chronic conditions in later life than unfit persons and had a lesser burden of chronic disease before death.

Physically active vs. inactive lifestyle, muscle properties, and glucose homeostasis in middle-aged and older twins

Exercise-induced positive changes in skeletal muscle properties and metabolism decrease the risk for disability, cardiometabolic diseases and mortality. Here, we studied muscle properties and glucose homeostasis in a non-exercise stage in twin pairs with co-twins discordant for physical activity habits for at least 32 years of their adult lives. Isometric knee extension force, MR imaging of midthigh tissue composition and muscle volume, and fasting blood samples were acquired from 16 same-sex (seven monozygotic, nine dizygotic) middle-aged and older twin pairs. The consistently active twins had 20 % higher knee extension forces than their inactive co-twins (p = 0.006) although the active twins had only 4 % higher midthigh muscle cross-sectional areas (p = 0.072). These results were similar in intrapair analysis in which only the seven identical twin pairs were included. The ratio between the area of midthigh fat and muscle tissues was significantly lower among the active twins (0.65 vs. 0.48, p = 0.006). The active twins had also lower fasting plasma glucose levels (5.1 vs 5.6 mmol/l, p = 0.041). The area of midthigh intramuscular (extramyocellular) fat was associated with the markers of glucose homeostasis, especially with glycated hemoglobin, and these associations were emphasized by the diabetic and inactive twins. Regular exercise throughout the adult life retains muscle strength and quality but not necessarily mass. The regular use of muscles also prevents from the accumulation of intramuscular fat which might be related to maintained glucose metabolism and, thus, prevention of metabolic disorders.

Shared genetic influence of BMI, physical activity and type 2 diabetes: a twin study

AIMS/HYPOTHESIS

The aim of this study was to examine the long-term associations of BMI and physical activity with type 2 diabetes, and to estimate shared genetic components of these traits.

METHODS

We used data from the Swedish Twin Registry on 23,539 twins born 1886-1958 who answered questionnaires between 1967 and 1972 and were followed up until 1998. The risk of type 2 diabetes in relation to BMI and physical activity was assessed by Cox regression. Structural equation models were used to estimate genetic and environmental variance components and genetic correlations.

RESULTS

The risk of type 2 diabetes increased with BMI (HR 1.32 [95% CI 1.29, 1.35] per kg/m²) and decreased with physical activity (HR 0.56 [95% CI 0.39, 0.80] for high vs low). Heritability was estimated to be 77% (95% CI 54%, 83%) for type 2 diabetes, 65% (95% CI 58%, 73%) for BMI, and 57% (95% CI 47%, 67%) for physical activity. The genetic correlation with type 2 diabetes was 0.43 (95% CI 0.31, 0.58) for BMI and -0.23 (95% CI -0.46, 0.02) for physical activity, implying that 18% (95% CI 9%, 34%) of the genetic influence on type 2 diabetes is shared with BMI and 5% (95% CI 0%, 20%) with physical activity.

CONCLUSIONS/INTERPRETATION

Indications of shared genetic effects are found for BMI and type 2 diabetes, which suggests that these traits are partly influenced by the same genetic factors. In contrast, our findings suggest that the genes related to physical activity are essentially different from those associated with type 2 diabetes.

A prospective study of weight training and risk of type 2 diabetes mellitus in men

BACKGROUND The role of weight training in the primary prevention of type 2 diabetes mellitus (T2DM) is largely unknown. METHODS To examine the association of weight training with risk of T2DM in US men and to assess the influence of combining weight training and aerobic exercise, we performed a prospective cohort study of 32 002 men from the Health Professionals Follow-up Study observed from 1990 to 2008. Weekly time spent on weight training and aerobic exercise (including brisk walking, jogging, running, bicycling, swimming, tennis, squash, and calisthenics/rowing) was obtained from questionnaires at baseline and biennially during follow-up. RESULTS During 508 332 person-years of follow-up (18 years), we documented 2278 new cases of T2DM. In multivariable-adjusted models, we observed a dose-response relationship between an increasing amount of time spent on weight training or aerobic exercise and lower risk of T2DM (P &lt; .001 for trend). Engaging in weight training or aerobic exercise for at least 150 minutes per week was independently associated with a lower risk of T2DM of 34% (95% CI, 7%-54%) and 52% (95% CI, 45%-58%), respectively. Men who engaged in aerobic exercise and weight training for at least 150 minutes per week had the greatest reduction in T2DM risk (59%; 95% CI, 39%-73%). CONCLUSIONS Weight training was associated with a significantly lower risk of T2DM, independent of aerobic exercise. Combined weight training and aerobic exercise conferred a greater benefit.

Long-term leisure-time physical activity and serum metabolome

BACKGROUND

Long-term physical inactivity seems to cause many health problems. We studied whether persistent physical activity compared with inactivity has a global effect on serum metabolome toward reduced cardiometabolic disease risk.

METHODS AND RESULTS

Sixteen same-sex twin pairs (mean age, 60 years) were selected from a cohort of twin pairs on the basis of their >30-year discordance for physical activity. Persistently (≥5 years) active and inactive groups in 3 population-based cohorts (mean ages, 31-52 years) were also studied (1037 age- and sex-matched pairs). Serum metabolome was quantified by nuclear magnetic resonance spectroscopy. We used permutation analysis to estimate the significance of the multivariate effect combined across all metabolic measures; univariate effects were estimated by paired testing in twins and in matched pairs in the cohorts, and by meta-analysis over all substudies. Persistent physical activity was associated with the multivariate metabolic profile in the twins (P=0.003), and a similar pattern was observed in all 3 population cohorts with differing mean ages. Isoleucine, α1-acid glycoprotein, and glucose were lower in the physically active than in the inactive individuals (P<0.001 in meta-analysis); serum fatty acid composition was shifted toward a less saturated profile; and lipoprotein subclasses were shifted toward lower very-low-density lipoprotein (P<0.001) and higher large and very large high-density lipoprotein (P<0.001) particle concentrations. The findings persisted after adjustment for body mass index.

CONCLUSIONS

The numerous differences found between persistently physically active and inactive individuals in the circulating metabolome together indicate better metabolic health in the physically active than in inactive individuals.

Early determinants of type-2 diabetes

The global prevalence of type-2 diabetes (T2D) has more than doubled in the last 30 years and is predicted to continue to rise at an alarming rate. The associated health and financial burdens are considerable. The aetiology of common forms of T2D is multifactorial and involves a complex interplay between genetic, epigenetic and environmental factors. The influential role of the environment, in particular our diet and sedentary lifestyles, in diabetes risk is well established. Of major concern is the increasing prevalence of early onset T2D or pre-diabetic characteristics in children. In recent years, the role of the early life environment in programming diabetes risk has been the focus of numerous human and animal studies. Historical studies highlighted an association between low birthweight, a proxy for suboptimal in utero growth, and diabetes risk in adulthood. Over more recent years it has become apparent that a variety of expositions, including maternal obesity and/or maternal diabetes, can have a significant effect on offspring health outcomes. Further complicating matters, paternal and transgenerational transmission of T2D can occur thus mediating a perpetuating cycle of disease risk between generations. It is imperative for the underlying mechanisms to be elucidated so that interventions can be introduced. In doing so, it may be possible to prevent, delay or reverse a pre-programmed risk for T2D induced by pre- and/or postnatal environmental factors to improve health outcomes and curb premature metabolic decline. This review presents evidence for how the early life environment may programme T2D risk and suggests some mechanisms by which this may occur.

Perceived need to increase physical activity levels among adults at high risk of type 2 diabetes: a cross-sectional analysis within a community-based diabetes prevention project FIN-D2D

BACKGROUND

Increased physical activity is a cornerstone of type 2 diabetes prevention. The perception of a need to change is considered essential in behaviour change processes. However, the existing literature on individuals' perceived need to change health behaviour is limited. In order to improve understanding of diabetes prevention through increased physical activity levels (PAL), we assessed factors associated with perceiving a need to increase PAL among adults at high risk of diabetes.

METHODS

Opportunistic screening was used within a primary-care based lifestyle intervention covering 10 149 men and women at high risk of type 2 diabetes. Data were obtained at baseline visits. The explored determinants were demographic, anthropometric/clinical, behavioural and psychosocial characteristics, along with four categories of PAL awareness. Logistic regression was used in the analysis.

RESULTS

74% of men (n = 2 577) and 76% of women (n = 4 551) perceived a need to increase their PAL. The participants most likely to perceive this need were inactive, had a larger waist circumference, rated their PAL as insufficient, and were at the contemplation stage of change. Smoking, elevated blood pressure, dyslipidaemia, and a family history of diabetes were not associated with this perception. The likelihood was also greater among women with less perceived fitness and less education. Demographic factors other than education did not determine participants' perceived need to increase PAL. PAL overestimators were less likely to perceive the need to increase their PAL than realistic inactive participants.

CONCLUSIONS

Subjective rather than objective health factors appear to determine the perception of a need to increase PAL among adults at high risk of diabetes. Client perceptions need to be evaluated in health counselling in order to facilitate a change in PAL. Practical descriptions of the associations between metabolic risk factors, PAL, and diabetes are needed in order to make the risk factors concrete for at-risk individuals.

Increase in physical activity and cardiometabolic risk profile change during lifestyle intervention in primary healthcare: 1-year follow-up study among individuals at high risk for type 2 diabetes

Objectives To investigate the association between increase in physical activity and changes in cardiometabolic risk factors during a lifestyle intervention programme in routine clinical settings. Design Prospective follow-up. Setting 400 primary healthcare centres and occupational healthcare outpatient clinics in Finland. Participants Individuals at high risk for type 2 diabetes identified in the implementation project of the national diabetes prevention programme (FIN-D2D) and participating in baseline and 1-year follow-up visits. Final study group comprised the 1871 non-diabetic participants who responded at follow-up visit to a question on stability versus increase of physical activity. Interventions Lifestyle intervention. Primary outcome measures Cardiometabolic risk factors (body composition, blood pressure and those measured from fasting venous blood samples) measured at baseline and follow-up visits. Results Of the participants, 310 (16.6% of all responders) reported at follow-up having clearly increased their physical activity during the past year, while 1380 (73.8%) had been unable to increase their physical activity. Those who increased their activity decreased their weight by 3.6 kg (95% CI 2.9 to 4.3, age and sex adjusted, p<0.001) and waist circumference by 3.6 cm (95% CI 2.9 to 4.3, p<0.001) more than those who did not increase their activity. Similarly, those who increased their physical activity had greater reductions in total cholesterol (group difference in reduction 0.17 mmol/l, 95% CI 0.06 to 0.28, p=0.002), low-density lipoprotein cholesterol (0.16 mmol/l, 95% CI 0.06 to 0.26, p=0.001), low-density lipoprotein/high-density lipoprotein ratio (0.17, 95% CI 0.08 to 0.25, p<0.001) as well as fasting glucose (0.09 mmol/l, 95% CI 0.03 to 0.15, p=0.004) and 2 h glucose levels (0.36 mmol/l, 95% CI 0.17 to 0.55, p=0.023) than those who did not increase their physical activity. Conclusion Increasing physical activity seems to be an important feature of cardiometabolic risk reduction among individuals at high risk for type 2 diabetes participating in preventive interventions in routine clinical settings.

Causes and consequences of obesity: the contribution of recent twin studies

Obesity is a genetically complex disorder that produces a myriad of health problems. Most of the recognized complications of obesity are not only strongly influenced by lifestyle factors, but also present with independent genetic predispositions that are notoriously difficult to disentangle in humans. Most studies on the causes and consequences of acquired obesity are encumbered by the incomplete ability to control for genetic influences. However, utilizing a unique experiment of nature, namely monozygotic twins (MZ) discordant for obesity as 'clonal controls' of obese and non-obese individuals has enabled the fine characterization of the effects and possible antecedents of acquired obesity while controlling for the genetic background, as well as pointed to novel obesity predisposing candidate genes. This review is a distillation of the findings from more than 10 years of research done in an exceptionally well-characterized collection of MZ and dizygotic (DZ) twins, based on the Finnish Twin Cohorts. Topics covered include the nature of development of obesity from the childhood onwards, the role of exercise in modifying the genetic susceptibility, the resulting inflammatory, prediabetic and preatherosclerotic changes in whole body and adipose tissue physiology, as well as the newest insights provided by the omics revolution.

Leisure time physical activity in patients with epilepsy in Seoul, South Korea

The aim of this study was to investigate the frequencies of and barriers to leisure time physical activity (LTPA) of people with epilepsy (PWE), and influencing factors, particularly those related to mood. Data were obtained from 178 PWE who visited the Seoul National University Hospital outpatient clinic in January and February 2007. Most PWE reported not being involved in LTPA as much as they wished. PWE reported hiking (n=32, 18%) and walking (n=25, 14%) as the most common LTPA. Many PWE identified epilepsy-specific barriers such as "the fear of experiencing seizures during activity" and "discouragement from activity by family and/or friends." In multiple logistic regression analysis, PWE who were on antiepileptic drug polytherapy (OR=2.49, 95% CI=1.22-5.08, P=0.01), had anxiety (OR=3.25, 95% CI=1.22-8.60, P=0.02), and had had previous seizure experiences during activities (OR=2.84, 95% CI=1.30-6.20, P=0.01) were significantly more likely to be inactive. Educational programs for reducing anxiety and misunderstanding about activity of PWE and guidelines for promoting LTPA among PWE are needed.

Physical activity, genes, and lifetime predisposition to chronic disease

This mini-review summarizes the main associations between physical activity and chronic diseases and discusses the basic concepts related to the role of genetic factors in studies evaluating the effects of physical activity/exercise therapy on chronic disease prevention/treatment during the life course. Many observational cohort studies have shown that high physical activity during young adulthood or middle age is associated with reduced later life morbidity, mobility limitations and mortality. Physical activity or exercise therapy has a positive effect on health via many disease-specific mechanisms. The most consistent finding of the various randomized controlled studies conducted to date is that aerobic/functional capacity and/or muscle strength can be improved by exercise training among patients with different chronic diseases. Genes are known to play a role in chronic disease predisposition and to contribute to physical fitness levels, physical activity participation and ageing. Physical fitness, physical activity and health outcomes may be partly due to underlying genetic factors that have a favourable effect on all these traits (genetic pleiotropy). This means that in observational studies, the relationship between baseline activity and the later occurrence of diseases may not be interpreted entirely as causal. Increased knowledge on the role of nuclear genome, mitochondrial genome, epigenetics, telomeres and regulation of gene expression will increase our understanding of their relationships with physical activity and morbidity.