• Diabetes, Sarcopenia, Peripheral Nerve & Lower Extremity Function in Older Adults

      Chiles Shaffer, Nancy; Orwig, Denise L. (2014)
      Diabetes is associated with lower extremity dysfunction. Sarcopenia, a geriatric syndrome that indicates loss of muscle mass and strength, is also associated with lower extremity dysfunction. Sarcopenia may be more prevalent among diabetic older adults. Peripheral nerve dysfunction (PND) has been suggested as a mechanistic cause of sarcopenia. This relationship between PND and sarcopenia has not been examined longitudinally in any cohort. Additionally, research has not examined the association between diabetes, sarcopenia, and lower extremity function (LEF) longitudinally. The specific aims of this study were to: 1) Examine the prevalence of sarcopenia among a US population of diabetic and non-diabetic older adults, and effect modification of sex and race, using multivariable logistic regression; 2) Examine the relationship between PND and sarcopenia among diabetic and non-diabetic older adults over time and determine if race and sex modify the relationship using generalized estimating equations; 3) Identify the relationship of PND and sarcopenia on LEF among diabetic compared to non-diabetic older adults, and examine if race or sex modify the relationship, using generalized linear models. A secondary analysis of the Health, Aging, and Body Composition (Health ABC) study (1997-2008) was conducted on 2388 (1884 non diabetics and 504 diabetics) community-dwelling black (932) and white (1456) individuals aged 70 years and older, over study years 1-11. Diabetes was determined from blood glucose, use of antidiabetic medications, and/or self-report of a previous diagnosis. Sarcopenia classification was based on DXA-measured appendicular lean mass normalized for height, and grip strength. LEF was measured by gait speed. Sarcopenia prevalence was lower for diabetics than non-diabetics older adults. Adjusting for covariates, neither diabetes nor PND were associated with increased prevalence of sarcopenia. Sarcopenia prevalence was significantly associated with a slower gait speed over time. Sex and race did not modify any of the relationships. Our findings indicate that diabetes is not predictive of sarcopenia prevalence over time; however sarcopenia is predictive of slower gait speed. Further refinement of the definition of sarcopenia may be necessary to account for muscle quality, specifically fat infiltration, which may exist among diabetic older adults. quality, specifically fat infiltration, which may exist among diabetic older adults.
    • Sarcopenia and PRAISEDD-2 Intervention's Impact on Diet, Physical Activity, and Body Composition

      Hammersla, Margaret; Resnick, Barbara (2017)
      Background: Older adults with a low socioeconomic status and African Americans are more sedentary than the general population. This contributes to the development of sarcopenia and has a negative impact on the health and function of these individuals. PRAISEDD-2 was a 24-month quasi-experimetnal study of low income adults living in senior housing. A focused 3-month intervention included education about stroke prevention and heart health through adherence to heart healthy diets, regular exercise, and prescribed medication combined with exercise classes that included verbal encouragement, blood pressure feedback, and role modeling. Classes continued to be offered in months 4-24 but only included a monthly motivational intervention. The impact of the PRAISEDD-2 intervention on diet (fat, sodium, and protein intake), time spent in physical activity, and body composition are examined in the study reported here. Design: Diet and body composition measures were collected at baseline, 3, 6, 12, and 24 months. Sample included 29 residents of a low-income senior housing complex in Baltimore, MD. Complete data was obtain from 13 participants. Generalized estimating equations (GEE) were used to examine change over the time periods. An intention-to-treat (ITT) paradigm was followed. Results: At 3 months, participants experienced a decrease in sodium (p<0.01) and fat intake (p<0.01), as well as in a decrease in percent body fat (p<.001). However, at 24 months, fat intake (p<0.001) and percent body fat (p<0.001) increased, although protein intake increased (p<.001). No significant change was noted in physical activity (p=.056) or sodium intake (p=0.69) at 24 months. Conclusions: The findings from this study provided some support for the feasibility and preliminary efficacy of the PRAISEDD-2 intervention. The changes that occurred in the early 3 month period were likely due to the intensive nature of the education and exercise classes. Future research should focus on building a stronger self-efficacy based motivational component into the exercise classes to strengthen long term adherence to the recommended dietary change and physical activity, essential to promote decrease in body fat and increases in muscle mass. Interventions may need to be sustained longer to achieve more permanent changes in diet and exercise.