Habitual physical activity and cardiometabolic risk factors in adults with cerebral palsy.

Adults with cerebral palsy (CP) are known to participate in reduced levels of total physical activity. There is no information available however, regarding levels of moderate-to-vigorous physical activity (MVPA) in this population. Reduced participation in MVPA is associated with several cardiometabolic risk factors. The purpose of this study was firstly to compare levels of sedentary, light, MVPA and total activity in adults with CP to adults without CP. Secondly, the objective was to investigate the association between physical activity components, sedentary behavior and cardiometabolic risk factors in adults with CP. Adults with CP (n=41) age 18-62 yr (mean ± SD=36.5 ± 12.5 yr), classified in Gross Motor Function Classification System level I (n=13), II (n=18) and III (n=10) participated in this study. Physical activity was measured by accelerometry in adults with CP and in age- and sex-matched adults without CP over 7 days. Anthropometric indicators of obesity, blood pressure and several biomarkers of cardiometabolic disease were also measured in adults with CP. Adults with CP spent less time in light, moderate, vigorous and total activity, and more time in sedentary activity than adults without CP (p<0.01 for all). Moderate physical activity was associated with waist-height ratio when adjusted for age and sex (ß=-0.314, p<0.05). When further adjustment was made for total activity, moderate activity was associated with waist-height ratio (ß=-0.538, p<0.05), waist circumference (ß=-0.518, p<0.05), systolic blood pressure (ß=-0.592, p<0.05) and diastolic blood pressure (ß=-0.636, p<0.05). Sedentary activity was not associated with any risk factor. The findings provide evidence that relatively young adults with CP participate in reduced levels of MVPA and spend increased time in sedentary behavior, potentially increasing their risk of developing cardiometabolic disease.

Waist circumference provides an indication of numerous cardiometabolic risk factors in adults with cerebral palsy.

OBJECTIVE: To report the prevalence of cardiometabolic risk factors in a cohort of adults with cerebral palsy (CP) and to investigate the ability of anthropometric measures to predict these factors. DESIGN: Cross-sectional study. SETTING: Testing took place in a laboratory setting. PARTICIPANTS: Adults with CP (N=55; mean age, 37.5±13.3 y; Gross Motor Function Classification System levels, I-V) participated in this study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, insulin, and C-reactive protein levels were measured from a fasting venous blood sample. Insulin resistance was calculated using the Homeostasis Model Assessment (HOMA-IR) index. Blood pressure, body mass index (BMI), waist circumference (WC), waist-hip ratio, and waist-height ratio were also measured. The metabolic syndrome (MetS) was defined according to the 2009 Joint Interim Statement. RESULTS: The prevalence of the MetS was 20.5% in ambulatory adults and 28.6% in nonambulatory adults. BMI was associated with HOMA-IR only (ß=.451; P<.01). WC was associated with HOMA-IR (ß=.480; P<.01), triglycerides (ß=.450; P<.01), and systolic blood pressure (ß=.352; P<.05). Receiver operating characteristic curve analysis revealed that WC provided the best indication of hypertensive blood pressure, dyslipidemia, HOMA-IR, and the presence of multiple risk factors (area under the curve, .713-.763). CONCLUSIONS: A high prevalence of the MetS was observed in this relatively young sample of adults with CP. WC was a better indicator of a number of risk factors than was BMI and presents as a clinically useful method of screening for cardiometabolic risk among adults with CP.

Overview of human obesity and central mechanisms regulating energy homeostasis.

Obesity is now regarded as a global epidemic affecting both adults and children, and is associated with significant morbidity and mortality. Thus the effective management of obesity has become an important clinical focus. Therefore, an understanding of the pathways controlling appetite, satiety and food intake is critical for gaining an insight into the pathogenesis of obesity and also for the development of diagnostic tests and therapeutic agents for use in the clinical management of this condition. Over the last decade or more research using both mouse and human genetic models has elucidated the critical role of the leptin-melanocortin pathway in the hypothalamus, in regulating mammalian energy balance. In tandem with this, a clearer understanding of the regulation of gut-derived hormones and their interaction with the central nervous system has further illuminated the complex interplay between central and peripheral aspects of energy regulation. The obesity epidemic and the expanded knowledge base relating to its aetiopathogenesis have specific implications for clinical biochemistry. In particular, an increase in workload may be expected due to biochemical investigation of obesity and its co-morbidities. Moreover, advice on the in-depth investigation of complex cases of obesity may be sought, including information on newer diagnostic tests, such as serum leptin or molecular genetic analysis. There may also be a substantive role for chemical pathologists in establishing and running clinical obesity services. Finally, clinical biochemistry has a role in research pertaining to obesity and cardiometabolic risk.

PGC-1alpha genotype modifies the association of volitional energy expenditure with [OV0312]O2max.

UNLABELLED: Sedentary lifestyles are increasingly common and result in low cardiorespiratory fitness ([OV0312]O2max), a well-established predictor of early mortality and coronary heart disease (CHD). Adaptation in [OV0312]O2max after exercise training varies considerably between people. Because there are hereditary components to fitness, it is likely that genetic factors explain some of this variability. PPARGC1 (PGC-1alpha) coactivates genes involved in energy transduction and mitochondrial biogenesis. Transgenic mouse data demonstrate that overexpression of PGC-1alpha mRNA increases endurance capacity by transformation of nonoxidative to oxidative skeletal muscle tissue. Other murine studies demonstrate that exercise increases PGC-1alpha mRNA expression. PURPOSE: To explore whether a candidate polymorphism in the PGC-1alpha gene modifies the association between physical activity energy expenditure (PAEE) and predicted [OV0312]O2max ([OV0312]O2max.pred). METHOD: We examined whether the Gly482Ser polymorphism of PGC-1alpha modified the relationship between objectively measured PAEE and [OV0312]O2max.pred in a population-based sample of 599 healthy middle-aged people. PAEE was assessed using individual calibration with 4 d of heart rate monitoring. [OV0312]O2max.pred was measured during a submaximal exercise stress test on a bicycle ergometer. RESULTS: Homozygosity at the Ser482 allele was found in 12.7% of the cohort, whereas 38.9% and 48.4% carried the Gly482Gly and Gly482Ser genotypes, respectively. The association between PAEE and [OV0312]O2max.pred (mL x kg(-1) x min(-1)) was strongest in people homozygous for the Ser482 allele (beta = 12.03; P < 0.00001) compared with carriers of the Gly allele (beta = 5.61; P < 0.00001). In a recessive model for the Ser482 allele, the interaction between PAEE and genotype on [OV0312]O2max.pred (L x min(-1)) was highly significant (P = 0.009). CONCLUSION: Our results indicate that Ser482 homozygotes may be most capable of improving cardiorespiratory fitness when physically active, and that Gly482Ser may explain some of the between-person variance previously reported in cardiorespiratory adaptation after exercise training.

Obesity therapy: altering the energy intake-and-expenditure balance sheet.

Obesity is associated with numerous health complications, which range from non-fatal debilitating conditions such as osteoarthritis, to life-threatening chronic diseases such as coronary heart disease, diabetes and certain cancers. The psychological consequences of obesity can range from lowered self-esteem to clinical depression. Despite the high prevalence of obesity and the many advances in our understanding of how it develops, current therapies have persistently failed to achieve long-term success. This review focuses on how fat mass can be reduced by altering the balance between energy intake and expenditure.