«Posture, Mobility, and 30-day Hospital Readmission in Older Adults with Heart Failure by Theresa A. Floegel A Dissertation Presented in Partial ...»
Posture, Mobility, and 30-day Hospital Readmission
in Older Adults with Heart Failure
Theresa A. Floegel
A Dissertation Presented in Partial Fulfillment
of the Requirements for the Degree
Doctor of Philosophy
Approved July 2015 by the
Graduate Supervisory Committee:
Matthew Buman, Chair
Cheryl Der Ananian
ARIZONA STATE UNIVERSITY
Background: Heart failure is the leading cause of hospitalization in older adults and has the highest 30-day readmission rate of all diagnoses. An estimated 30 to 60 percent of older adults lose some degree of physical function in the course of an acute hospital stay.
Few studies have addressed the role of posture and mobility in contributing to, or improving, physical function in older hospitalized adults. No study to date that we are aware of has addressed this in the older heart failure population.
Purpose: To investigate the predictive value of mobility during a hospital stay and patterns of mobility during the month following discharge on hospital readmission and 30-day changes in functional status in older heart failure patients.
Methods: This was a prospective observational study of 21 older (ages 60+) patients admitted with a primary diagnosis of heart failure. Patients wore two inclinometric accelerometers (rib area and thigh) to record posture and an accelerometer placed at the ankle to record ambulatory activity. Patients wore all sensors continuously during hospitalization and the ankle accelerometer for 30 days after hospital discharge. Function was assessed in all patients the day after hospital discharge and again at 30 days postdischarge.
Results: Five patients (23.8%) were readmitted within the 30 day post-discharge period.
None of the hospital or post-discharge mobility measures were associated with readmission after adjustment for covariates. Higher percent lying time in the hospital was associated with slower Timed Up and Go (TUG) time (b =.08, p =.01) and poorer hand grip strength (b = -13.94, p =.02) at 30 days post-discharge. Higher daily stepping i activity during the 30 day post-discharge period was marginally associated with improvements in SPPB scores at 30 days (b =.001, p =.06).
Conclusion: For older heart failure patients, increased time lying while hospitalized is associated with slower walking time and poor hand grip strength 30 days after discharge.
Higher daily stepping after discharge may be associated with improvements in physical function at 30 days.
This dissertation would have remained a dream for me had it not been for the many people at Arizona State University who stood behind and beside me. It is with immense gratitude that I acknowledge my committee chair and mentor, Dr. Matthew Buman, for encouraging me to pursue my interests and push myself to achieve the most that I could in this program. You gave me the freedom to explore areas I found interesting, while providing the support to refine and develop my ideas. Your passion to share your research knowledge is not matched by anyone else I know. Because of you I feel I am prepared to embark on a new career in research.
Each of my committee members has played an important role in helping me transform into a true scientific researcher. Dr. Steven Hooker, Dr. Cheryl DerAnanian, Dr. Jared Dickinson, and Dr. Marianne McCarthy, many thanks to each of you for helping me realize my passion for Gerontological research, support along the way with your sound advice, critique, and encouragement, and professional friendship.
My research was supported by the Hartford Center for Gerontological Nursing Excellence Scholarship Program. Thank you Dr. Nelma Shearer and Dr. Adrianna Perez for your encouragement to apply to the program. You both have supported my development into a budding Gerontological nursing scholar.
Erin Krzywicki, my research assistant and colleague, who has been with me through my dissertation research journey, thank you for your professional support, hard work, and humor. You kept us sane and I could not have done this with you. Cheryl Dodson, Serena Roberts, heart failure coordinators, and Dr. Sabbath and Dr. Birkholz
their patients. I am deeply thankful for your support and professional friendship.
I am indebted to my doctoral cohort colleagues, Alberto Florez, Jessica Knurick, Andrew Miller, Wesley Tucker, and Wenfei Zhu, who helped me through this journey providing both academic and research support and personal friendship.
Lastly, and most importantly, I want to acknowledge and thank my husband, Michael, for his tireless support, love, and willingness to be my punching bag when needed. And my children, Courtney and Thomas, who have been schooling side-by-side with me, for their love and support, and ability to slip in humorous breaks from schoolwork (mine, not theirs) when I needed it.
LIST OF TABLES
LIST OF FIGURES
CHAPTER 1 INTRODUCTION
Statement of the Problem
Specific Aim 1...
Specific Aim 2…..
2 LITERATURE REVIEW
Normal Aging versus Chronic Disease
Heart Failure in an Aging Population
Mobility Decline in an Aging Population
Mobility/Function Measurement in Hospitalized Older Adults and Associated Outcomes.
Mobility/Functional Interventions for Acute Hospitalization and Rehabilitation…………………………………………………………43 3 METHODS
Data Selection for Prediction Models
Summary of Findings
Specific Aim 1
Specific Aim 2
Strengths and Limitations
APPENDIX A PHOTOS AND PLACEMENT DIAGRAM OF MONITORS............... 120 B PATIENT AND STAFF INFORMATION
C TRACTIVITY INFORMATION FOR HOME MONITORING............ 126
1. Normative Values for Timed Up and Go Test
2. Hospital Metrics for Analysis……………….…………………………………….58
3. Post discharge Metrics for Analysis
4. Pearson Correlation Coefficients for Activity Measures
5. Covariates, Aim 1
6. Covariates, Aim 2
7. Demographic and Health History of Heart Failure Participants
8. Hospital Characteristics of Participants
9. Percent of Hospital Day in Three Postures, Number Transitions, Steps/Day........ 78 10. 30 Day Post Discharge Step Activity
11. Functional Outcomes
12. Associations and Odds Ratios of Hospital Metrics
13. Associations between Hospital Metrics and Function
14. Associations and Odds Ratios of Discharge Metrics……………………………...86
15. Associations between Changes in Mobility and Function ……………......……..87
1. Measurement of Physical Function and Physical Activity in Older Adults …... 23
2. Study Timeline
3. Normality Plot I …..
4. Normality Plot II
5. Normality Plot III
6. Flow Diagram of Participant Recruitment and Retention …..
7. Association between Lying Time and TUG Scores
8. Association between Lying Time and Hand grip Strength
9. SPPB Score Increase and Mean Stepping from Post-Discharge Day 1 to 30.…. 88
Mobility— the ability of an individual to purposively move about his or her environment (Rosso, Taylor, Tabb, & Michael, 2013).
Functional decline—the decrement in physical and/or cognitive functioning that occurs when a person is unable to engage in activities of daily living.
Functional independence—the ability to perform daily living activities safely and autonomously (Covinsky et al., 2003).
Length of stay—based on 24-hour clock, the number of days residing in the hospital, including day of admission and day of discharge.
Comorbidity—the simultaneous presence of 2+ morbid conditions or diseases in the same person (Segen, 2002).
Readmission—a subsequent unplanned hospital admission within 30 days following an original admission.
Heart failure class I, II, III, IV— the New York Heart Association Functional
Classification System (NYHA) classifies heart failure patients according to three criteria:
1) limitations on physical activity, 2) symptoms (e.g. fatigue) and, 3) patient status at rest.
Class I patients have cardiac disease present but suffer no symptoms during rest or
physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea or anginal pain. Class III patients have cardiac disease resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes fatigue, palpitation, dyspnea or anginal pain. Class IV patients suffer symptoms of fatigue, dyspnea, or angina pain to a degree at rest and with any level of physical activity (Dolgin, 1994).
Ejection Fraction—a measurement of how much blood the left ventricle pumps out with each contraction (Huether & McCance, 2008). For example, an ejection fraction of 60 percent means that 60 percent of the total amount of blood in the left ventricle is pushed out to the systemic circulation with each heartbeat.
Brain-Type Natriuretic Peptide (BNP)—a blood marker for prognosis and risk stratification in heart failure. BNP levels are highly correlated with the severity of heart failure but does not provide a definitive diagnosis (Kim & Januzzi, 2011).
Hand-Held Dynamometry—portable device that can be used to obtain objective measures of upper extremity strength during manual muscle testing (Roberts et al., 2014).
Over the next two decades, the older adult population (ages 65+) in the United States will more than double from 30 million to 80 million and older elderly adults— those more than 75 years of age —will soon have the highest growth rate of any age group (U. S. Centers for Disease Control and Prevention, 2012). Aging is associated with a higher prevalence of chronic disease that can negatively affect the older adult’s physical and functional abilities (Covinsky et al., 2003). An estimated 80 percent of older adults in the U. S. currently suffer from one or more chronic conditions (U. S. Centers for Disease Control and Prevention, 2011). Heart failure—a major chronic health condition of older age—greatly contributes to decline in the older adult’s physical function level, thus affecting self-care abilities. As heart failure progresses older adults often experience frequent exacerbations from which they may not fully recover. This continued decline places the heart failure population at a high risk for dependence on others and is a catalyst to frequent hospitalization and long-term institutionalization. In spite of modern therapies, half of older adults diagnosed with heart failure will die within five years (Go et al., 2014) and quality of life deteriorates quickly in another one third of this population (Blecker, Paul, Taksler, Ogedegbe, & Katz, 2013).
Heart failure is the leading cause of hospitalization in older adults, accounting for more than one million U.S. hospitalizations annually and contributing to an additional two to three million admissions (Go et al., 2014; Blecker et al., 2013). In 2007, older adults with heart failure accounted for 14 percent of the Medicare population yet consumed 43 percent of the Medicare budget, with much of the cost burden attributed to hospitalization (Linden & Adler-Milstein, 2008). The current medical cost of caring for heart failure patients in the U. S. is $32 billion annually and with the explosive growth of the older population is predicted to be more than $77 billion by 2030 (Heidenreich et al., 2011).
The compounding of physiologic events related to heart failure often causes a greater loss of physical function for the patient and they may require hospitalization.