Data Interpretation, Statistical

Publication Title: 
Mechanisms of Ageing and Development

Accessible and readily utilized software, tables and approximation formulae have been developed to estimate power and sample size for studies of time to event (survival times) when the survival times are assumed to be exponential. These methods can markedly misestimate power when the distribution is Weibull and not exponential. The Weibull distribution with increasing hazard is common in aging research, especially when the whole life span of the subjects is of interest.

Author(s): 
Heo, M.
Faith, M. S.
Allison, D. B.
Publication Title: 
Annals of the New York Academy of Sciences

Little effort has been directed toward studying the relationship between morbidity and mortality at exceptional ages, perhaps for no better reason than it has been difficult to do given available data resources. Two study innovations/adjustments are required to adequately represent count data with reports of health from aged sample persons. These design features are oversampling of the exceptional group and linkage to detailed administrative reports. The National Long-Term Care Survey (NLTCS) has made it possible to study health and functioning in the context of exceptional longevity.

Author(s): 
Corder, Larry S.
Publication Title: 
Biometrics

In the Georgia Centenarian Study (Poon et al., Exceptional Longevity, 2006), centenarian cases and young controls are classified according to three categories (age, ethnic origin, and single nucleotide polymorphisms [SNPs] of candidate longevity genes), where each factor has two possible levels. Here we provide methodologies to determine the minimum sample size needed to detect dependence in 2 x 2 x 2 tables based on Fisher's exact test evaluated exactly or by Markov chain Monte Carlo (MCMC), assuming only the case total L and the control total N are known.

Author(s): 
Dai, Jianliang
Li, Li
Kim, Sangkyu
Kimball, Beth
Jazwinski, S. Michal
Arnold, Jonathan
Georgia Centenarian Study
Publication Title: 
Advances in Gerontology = Uspekhi Gerontologii / Rossi?skai?a Akademii?a Nauk, Gerontologicheskoe Obshchestvo

We studied the basic indicators of immune status of healthy persons of different age groups living in the monsoon climate in the southern Far East. The analysis shows age-dependent development of immunodepressive status, combined with increasing levels of CD16, CD25 and HLA-DR in the aging organism. Climatic and anthropogenic factors effect profoundly damaging on the body, which results in the severity of disorders of the immune system in old, old age and longevity.

Author(s): 
Gvozdenko, T. A.
Kytikova, O. Iu
Vitkina, T. I.
Borshchev, P. V.
Publication Title: 
Brain, Behavior, and Immunity

Relatively short telomere length may serve as a marker of accelerated aging, and shorter telomeres have been linked to chronic stress. Specific lifestyle behaviors that can mitigate the effects of stress might be associated with longer telomere lengths. Previous research suggests a link between behaviors that focus on the well-being of others, such as volunteering and caregiving, and overall health and longevity.

Author(s): 
Hoge, Elizabeth A.
Chen, Maxine M.
Orr, Esther
Metcalf, Christina A.
Fischer, Laura E.
Pollack, Mark H.
De Vivo, Immaculata
Simon, Naomi M.
Publication Title: 
Aging Cell

Loss of nonshivering thermogenesis in mice by inactivation of the mitochondrial uncoupling protein gene (Ucp1-/- mice) causes increased sensitivity to cold and unexpected resistance to diet-induced obesity at a young age. To clarify the role of UCP1 in body weight regulation throughout life and influence of UCP1 deficiency on longevity, we longitudinally analyzed the phenotypes of Ucp1-/- mice maintained in a room at 23 degrees C.

Author(s): 
Kontani, Y.
Wang, Y.
Kimura, K.
Inokuma, K.-I.
Saito, M.
Suzuki-Miura, T.
Wang, Z.
Sato, Y.
Mori, N.
Yamashita, H.
Publication Title: 
Revista EspaÒola De CardiologÌa

We carried out a multicenter cross-sectional study in Argentina to investigate the prevalence of behavioral and other risk factors for coronary heart disease in patients aged 90 years or more and to study the association between risk factors and longevity. Data were collected on 322 individuals aged 90 years or more, 47% of whom had a family history of longevity. The majority ate meals comprising mainly fruit, milk and vegetables every day and half of the participants drank a moderate amount of red wine.

Author(s): 
Paterno, Carlos A.
Cornelio, Cecilia I.
GimÈnez, Juan C.
Publication Title: 
Aging Cell
Author(s): 
Pollak, Michael
Publication Title: 
Physiology & Behavior

Long-term exposure to stress and its physiological mediators, in particular cortisol, may lead to impaired telomere maintenance. In this study, we examine if greater cortisol responses to an acute stressor and/or dysregulated patterns of daily cortisol secretion are associated with shorter telomere length. Twenty-three postmenopausal women comprising caregivers for dementia partners (n=14) and age- and BMI-matched non-caregivers provided home sampling of cortisol-saliva samples at waking, 30 min after waking, and bedtime, and a 12-hour overnight urine collection.

Author(s): 
Tomiyama, A. Janet
O'Donovan, Aoife
Lin, Jue
Puterman, Eli
Lazaro, Alanie
Chan, Jessica
Dhabhar, Firdaus S.
Wolkowitz, Owen
Kirschbaum, Clemens
Blackburn, Elizabeth
Epel, Elissa
Publication Title: 
Physiology & Behavior

Long-term exposure to stress and its physiological mediators, in particular cortisol, may lead to impaired telomere maintenance. In this study, we examine if greater cortisol responses to an acute stressor and/or dysregulated patterns of daily cortisol secretion are associated with shorter telomere length. Twenty-three postmenopausal women comprising caregivers for dementia partners (n=14) and age- and BMI-matched non-caregivers provided home sampling of cortisol-saliva samples at waking, 30 min after waking, and bedtime, and a 12-hour overnight urine collection.

Author(s): 
Tomiyama, A. Janet
O'Donovan, Aoife
Lin, Jue
Puterman, Eli
Lazaro, Alanie
Chan, Jessica
Dhabhar, Firdaus S.
Wolkowitz, Owen
Kirschbaum, Clemens
Blackburn, Elizabeth
Epel, Elissa

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