<LEAP> highlights the findings and application of Cochrane reviews and other evidence pertinent to the practice of physical therapy. The Cochrane Library is a respected source of reliable evidence related to health care. Cochrane systematic reviews explore the evidence for and against the effectiveness and appropriateness of interventions—medications, surgery, education, nutrition, exercise—and the evidence for and against the use of diagnostic tests for specific conditions. Cochrane reviews are designed to facilitate the decisions of clinicians, patients, and others in health care by providing a careful review and interpretation of research studies published in the scientific literature.1 Each article in this PTJ series summarizes a Cochrane review or other scientific evidence on a single topic and presents clinical scenarios based on real patients or programs to illustrate how the results of the review can be used to directly inform clinical decisions. This article focuses on an 80-year-old woman with heart failure and the impact of exercise training on adverse event risk and quality of life. Can exercise training reduce the risk of adverse events and improve the quality of life in individuals with heart failure?
Approximately 5.7 million Americans are now diagnosed with heart failure (HF), with a current incidence of 670,000 new cases each year.2 Approximately 1 million hospital discharges were attributable to HF in 2007, a trend that has not changed since 1997.2 Similar statistics have been observed throughout the world, and the cost of medical care for HF constitutes a substantial proportion of total health care expenditure.2,3 Given the aging trends in the US population and other nations and the fact that HF primarily affects the elderly population, the incidence, prevalence, and hospitalization and mortality rates of this cardiac condition will likely increase.2,3 These statistics clearly demonstrate the magnitude of HF's current effect on health care systems on a global scale.2,3
Functional impairment and diminished quality of life are hallmark characteristics of HF.4–7 The cardiovascular, pulmonary, and musculoskeletal systems are all negatively affected by HF to varying degrees, and the magnitude by which they are impacted correlates with the degree of functional impairment observed clinically.4,5 The muscle hypothesis of chronic heart failure provides a comprehensive rationale of how left ventricular dysfunction, over time, can have substantial detrimental effects on multiple physiologic systems and produce the signs and symptoms associated with HF.6,7 Fortunately, exercise training has repeatedly been shown to improve aerobic capacity and muscle strength in patients diagnosed with HF when appropriate training stimuli are provided.8–12
The impact of exercise rehabilitation on risk of adverse events and quality of life in patients with HF was not addressed in a Cochrane review published in 2004 due to a lack of data at the time of publication.12 Thus, the 2010 Cochrane review by Davies et al13 sought to extend the initial review conducted in 2004 and determine the effects of exercise-based rehabilitation on mortality, hospitalizations, and quality of life in patients with HF. Nineteen randomized controlled trials, with a total of 3,674 participants, were included in this analysis. A single trial (Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing [HF-ACTION]) contributed more than 60% of the participants included in the final analysis.14 The Table outlines the findings of the 2010 Cochrane review.
Key Results From the 2010 Cochrane Review13,a
Take-Home Message
The Cochrane review by Davies et al13 showed no significant difference in mortality between exercise and usual care. Importantly, exercise training did not result in an increase in mortality. The number of HF-related hospitalizations was significantly less in individuals participating in exercise training. Lastly, studies assessing the impact of exercise training on quality of life clearly demonstrated a significant improvement following exercise intervention compared with usual care. The improvement in quality of life was consistent regardless of the tool that was utilized to quantify this important clinical variable. These findings add valuable information to the previous Cochrane review that clearly demonstrated exercise training significantly improves functional capacity in patients with HF.12
Case #11: Applying Evidence to a Patient With Acute HF
Is an exercise training program likely to benefit an 80-year-old woman with recurrent episodes of acute HF requiring frequent hospital admission?
Mrs X is an 80-year-old woman with a recent admission to a skilled nursing facility (SNF) after 1 week of hospitalization for acute decompensated HF accompanied by marked dyspnea, fatigue, and activity intolerance. Over the previous 6 months, she was admitted to the hospital with acute decompensated HF 4 times. She reported difficulty sleeping in bed over the past several months due to an abrupt need to urinate and difficulty breathing after lying supine for approximately 30 minutes and had been sleeping in a reclining chair in a minimally reclined position (almost upright) for the month prior to admission to the hospital. The patient has been using a rolling walker to assist ambulation for the past several months, but she has fallen several times during ambulation, reporting that her “legs just give out.” She was unable to participate in gait training during the recent hospitalization due to fear of falling, but initiated a strength and gait/balance training program at the SNF. Mrs X's home ambulation had been limited to her bedroom, bathroom, and living room, occupying a total area of approximately 18 to 24 m (60–80 ft). The patient reports that she could ambulate only about 6 m (20 ft) with the rolling walker, requiring minimal assistance of one person, before stopping to rest due to dyspnea and fatigue. Physical therapist assessment of her lower-extremity strength was graded as 4/5 throughout the muscle groups of the right lower extremity and as 3/5 throughout the muscle groups of the left lower extremity.
Mrs X's past medical history included long-standing hypertension, hypercholesterolemia, third-degree heart block requiring a permanent pacemaker, depression and anxiety, and systolic as well as diastolic HF (ejection fraction=38% with elevated filling pressures). Her medications included 100 mg of losartan (Cozaar, Merck & Co Inc, West Point, Pennsylvania), 40 mg of simvastatin (Zocor, Merck & Co Inc), 5 mg of Coumadin (Bristol-Myers Squibb Co, Princeton, New Jersey), and 40 mg of controlled-release carvedilol (Coreg CR, GlaxoSmithKline, Research Triangle Park, North Carolina) on a daily basis and Ativan (Wyeth Laboratories Inc, Collegeville, Pennsylvania) as needed.
Mrs X lived with her husband in a ranch-style home with 3 steps to enter the home. Her husband has been assisting her with all basic and instrumental activities of daily living for the past 3 months. She completed the Minnesota Living With Heart Failure Questionnaire (MLWHFQ) upon admission to the SNF, revealing the effects of HF on her quality of life. The maximum total score using the 5-point Likert scale from the 21 questions of the MLWHFQ is 105 points (range=0–105; higher scores equate to poorer quality of life, with a minimal clinically important difference of 5 points on the total score), and the patient was observed to have a total score of 90 points (eAppendix). The physical therapist at the SNF administered the MLWHFQ to identify the patient's perceived limitations and to focus on specific exercises to alleviate the limitations. On examination, there was no evidence of acute HF (no third heart sound, evidence of crackles in any lung field, peripheral edema, or dyspnea at rest; a hospital discharge B-type natriuretic peptide [BNP] value of 68 pg/mL confirmed an absence of acute HF).
Mrs X received 2 weeks of daily physical therapy at the SNF consisting of, on average, 10 minutes of strengthening exercises (using 0.45- and 0.91-kg [1- and 2-lb] ankle weights for the upper and lower extremities, respectively, with an average of 10 repetitions per extremity) and 20 minutes of gait and balance training (using parallel bars initially and progressing to her rolling walker), after which the medical team discharged her home with physical therapy and nursing services. Home health physical therapy consisted of similar exercises (however, strengthening exercises were administered with yellow Thera-Band [The Hygenic Corporation, Akron, Ohio]) in addition to diaphragmatic breathing exercises 2 to 3 times per week for 8 weeks. Exercise intensity at the SNF and at home was established at a rating of 3 to 4 using the 0 to 10 Modified Borg Dyspnea Scale, which was facilitated by giving Mrs X adequate rest periods between all exercise bouts.
How did the physical therapist apply the results of the Cochrane Systematic Review to the patient?
The physical therapist at the SNF was concerned about exercising Mrs X with HF and applied the Cochrane review findings using the PICO (Patient, Intervention, Comparison, Outcome) format. In regard to “Patient Relevance,” the physical therapist was most concerned about her sex and age, recent hospitalization for acute HF, and recurrent hospitalizations for HF. The therapist attempted to make sound clinical judgments regarding exercise based on the Cochrane review meta-regression results in which age, sex, and left ventricular ejection fraction were significant predictors of mortality or improvement in quality of life.13
In regard to “Intervention and Comparison Relevance,” the therapist used the Cochrane review to develop the exercise prescription, but applied a more conservative prescription than those reported in the review. The Cochrane review showed that the duration of exercise was 15 to 120 minutes per session, 2 to 7 days per week, at an intensity that varied considerably (40% of maximal heart rate to 85% of peak oxygen consumption). Thus, the physical therapist in the SNF decided to implement a low-level exercise program with frequent rest periods because of Mrs X's clinical status and acuity and the meta-regression findings that exercise training methods had no influence on outcomes. The meta-regression analyses revealed that exercise type and dose were not significant predictors of mortality or improvement in quality of life.13
The exercise prescription provided an average duration, frequency, and intensity of 30 minutes per day, 7 days per week, and 3 to 4 on the 0 to 10 Modified Borg Dyspnea Scale, respectively, and, therefore, was very much in keeping with the Cochrane review. The physical therapist also was concerned about administering resistance training in the SNF and home setting, but discovered that 5 studies used in the Cochrane review included resistance training and that a combination of rehabilitation center and home exercise was included in 8 of the Cochrane review studies. Furthermore, the Cochrane review reported that all studies included aerobic exercise, with exercise also being performed solely in rehabilitation centers (10 studies) and at home (1 study).
In regard to “Outcome Relevance,” the therapist realized that no adverse events were reported in the Cochrane review and again used the meta-regression results that no significant predictor of mortality was observed to support the exercise prescription that was administered. Furthermore, the significant improvement in quality of life with exercise rehabilitation that remained when all studies were pooled, regardless of the tool used, reassured the therapist that a good quality of life outcome was likely to occur for the patient as a result of the exercise program.
How well do the outcomes of the intervention provided to the patient match those suggested by the systematic review?
After 2 weeks of daily physical therapy at the SNF and 8 weeks of home physical therapy, Mrs X increased the strength in her upper and lower extremities by 0.5 to 1 point. Furthermore, she increased the distance ambulated in her home from 6.1 m (20 ft) to 12.2 m (40 ft) with a rolling walker and required only standby assistance while demonstrating less dyspnea and fatigue. Accompanying these improvements was a substantial decrease in the MLWHFQ total score (from 90 to 62 points; the mean change in the Cochrane review was 10 points), with similar improvements in the physical and psychological domains (see eAppendix). The number of hospital readmissions for HF was observed to decrease by half during the 6-month period following the initiation of exercise rehabilitation compared with the 6 months preceding the intervention. These outcomes contributed to an improved quality of life matching those of the systematic review.
Can you apply the results of the systematic review to your own patients?
The results of the PICO analysis described earlier suggest that the results of the Cochrane review can be cautiously applied to patients such as Mrs X. However, the results of the systematic review apply well to patients with systolic HF alone who are younger, male, and not recently hospitalized for acute HF. Although patients with diastolic HF were not included in the systematic review, it is likely that a number of the patients in the review had combined systolic and diastolic HF.15 Also, an emerging literature appears to support the role of exercise training in patients with diastolic HF.16–19 In view of these issues, the health care team believed it was reasonable to extrapolate the findings from the Cochrane review to this case.
Based on evidence from the systematic review described in this article, Mrs X, her physician, and the physical therapist agreed for exercise to be administered in the SNF and for Mrs X to begin a home-based program of exercise performed 2 to 3 times per week for 8 weeks that consisted of gait training, strengthening exercises with Thera-Band, and diaphragmatic breathing.
What can be advised based on the results of this systematic review?
The results of this systematic review suggest that patients with HF who are clinically stable are likely to benefit from an exercise training program. The beneficial results of exercise training in people with chronic HF include an improvement in quality of life and reduced hospitalizations. Although functional performance was not discussed in the current systematic review, patients with HF have been found to have improved functional, musculoskeletal, and cardiorespiratory performance after exercise training.8–12,14 Similar benefits appear to occur in patients with systolic and diastolic HF.17–19 Exercise training, therefore, has the potential to improve functional performance, quality of life, and rehospitalization rates for patients with HF.
- Received April 11, 2011.
- Accepted June 20, 2012.
- © 2012 American Physical Therapy Association