1Bureau USC. U.S. Census bureau projections show a slower growing, older, more diverse nation a half century from now, 2012. http://www.census.gov/newsroom/releases/archives/po-pulation/cb 12-243.html (accessed on September 20, 2014).
2Life expectancy, final 2007 data. http://www.cdc.gov/nchs/ fastats/lifexpec.htm. Accessed November 5, 2014.
3Go AS, Mozaffarian D, Roger VL, et al. Heart disease and stroke statistics-2014 update: A report from the American heart association. Circulation 2014; 129: e28-e292.
4Walston J, Hadley EC, Ferrucci L, et al. Research agenda for frailty in older adults: Toward a better understanding of physiology and etiology: Summary from the american geriat- rics society/national institute on aging research conference on frailty in older adults. JAm Geriatr Soc 2006; 54: 991-1001.
5Fried LP, Tangen CM, Walston J, et al. Frailty in older adults: Evidence for a phenotype. J Gerontol A Biol Sci Med Sci 2001; 56: 146-156.
6Ferrucci L, Guralnik JM, Studenski S, et al. Designing ran- domized, controlled trials aimed at preventing or delaying functional decline and disability in frail, older persons: A consensus report. JAm Geriatr Soc 2004; 52:625 -634.
7Chin A, Paw M J, Dekker JM, et al. How to select a frail eld- erly population? A comparison of three working definitions. J ClinEpidemiol 1999; 52:1015- 1021.
8Cigolle CT, Ofstedal MB, Tian Z, et al. Comparing models of frailty: The health and retirement study. J Am Geriatr Soc 2009; 57: 830-839.
9Walston J, McBurnie MA, Newman A, et al. Frailty and acti- vation of the inflammation and coagulation systems with and without clinical comorbidities: Results from the cardiovascu- lar health study. Arch Intern Med 2002; 162:2333-2341.
10Cesari M, Leeuwenburgh C, Lauretani F, et al. Frailty syn- drome and skeletal muscle: Results from the invecchiare in chianti study. Am J Clin Nutr 2006; 83:114-118.
