Women’s Health Initiative Observational Study (WHI-OS)38 examined as many as 23 variables, but did not investigate cognitive, nutritional, or blood measurement variables. In this study, all factors, with only 5 exceptions, were found to be associated with frailty in bivariate analyses, consistent with those reported in the WHI-OS. Other studies also have reported positive associations of frailty with age, stroke, COPD/asthma, visual impairment, and anemia.2, 18, 19, 39, 40 and 41 Interestingly, both Akt inhibitor this study and the WHI-OS found that cancer was not associated with frailty. Depression in particular appeared to be an important contributor, in agreement with other studies.16, 17, 18, 42 and 43 On the other hand, the association of cognitive impairment with frailty, as reported in other studies,12, 44 and 45 was observed only in bivariate analyses, but failed to be selected in the final model, plausibly because it was substituted by depression, stroke, and congestive heart failure, with which it also shares common pathophysiologic factors, such as atherosclerosis and chronic inflammation.46 and 47
Inadequate dietary intake and nutritional PLX4032 deficiencies are considered important causes of age-related sarcopenia, dynapenia, and frailty.48 and 49 Studies have shown that obesity, increased number of micronutrient deficiencies and low serum beta-carotenoids were significant risk factors for frailty,13 and 22 although one study using a detailed dietary questionnaire failed to demonstrate that low energy intake was significantly associated with frailty.49 Our study shows that in place of these nutritional variables, a simple screening measure of poor nutritional risk was independently associated with frailty. Elevated levels of immune markers of chronic inflammation, such as CRP and IL-6, Neratinib ic50 have been shown to be associated with frailty. In turn, circulating IL-6 level is inversely
associated with hemoglobin concentration in frail older adults, and low hemoglobin has been found to be independently associated with frailty. WCC is a well-recognized cellular marker of systemic inflammation and found in 2 studies to be associated with greater risk for cardiovascular disease, mortality, and frailty.15 and 20 Our study replicates the significant independent association of increased WCC with frailty. These results hence support the use of hemoglobin and WCC as simple, inexpensive, and routinely available clinical indicators of systemic inflammation and age-associated immune system decline associated with frailty. The 13 independent predictors selected in the final regression model represent an essential set of salient clinical risk indicators of prefrailty and frailty. It is noteworthy that these frailty risk factors are reflective of multiple system involvements for frailty.