Elsevier

Heart & Lung

Volume 32, Issue 1, January–February 2003, Pages 41-51
Heart & Lung

Issues in Cardiovascular Nursing
Six-minute walk performance and quality of life comparisons in North Carolina cardiac rehabilitation programs*,**

https://doi.org/10.1067/mhl.2003.7Get rights and content

Abstract

Objective: The purposes of this study were (1) to determine if six-minute walk (6MW) performance improved after short-term cardiac rehabilitation (CR) across multiple outpatient programs; (2) to examine differences in 6MW performance by patient age, sex, and race; and (3) to determine what relationships existed, if any, between 6MW performance and subscales of the Ferrans and Powers' Quality of Life Index—Cardiac Version III (QOLI). Design: Study design was nonexperimental, prospective, and comparative. Setting: Study setting included 14 outpatient CR programs from urban and rural settings across North Carolina. Patients: Adults aged 40 to 89 years (N = 630; men = 424 [67%], women = 206 [33%]; mean age, 61 ± 10.32 years) with medically or surgically treated coronary heart disease enrolled in outpatient CR. Outcome Measures: Study measures included scores on the QOLI and distance walked (feet) on the 6MW test. Results: Six-minute walk tests and QOLI surveys were administered before and immediately after short-term CR participation. Six-minute walk distance increased for all patients in all age categories across programs after CR (P <.0001). As a group, women improved 6MW distance by 15% (1243.9 ± 301.2 to 1435.3 ± 298.1; P <.001). Men also improved 6MW distance by 15% (1463.3 ± 339.5 to 1683.7 ± 346.9; P <.001) and walked farther than women on both the initial and follow-up 6MW tests (P <.0001). By age, there were no differences in 6MW scores between men and women aged 40 to 49 years (n = 58) and 50 to 59 years (n = 140; P = 0.54). Both of these age groups had greater initial and discharge 6MW scores than those aged 70 to 79 years (n = 183) and 80 to 89 years (n = 22; P <.001). Those aged 60 to 69 years (n = 227) had lower 6MW scores than those aged 40 to 49 years (P = 0.001) and 50 to 59 years (P <.05), and greater scores than those aged 70 to 79 years (P <.05) and 80 to 89 years (P <.05). Those aged 70 to 79 years had greater initial and follow-up 6MW scores than those aged 80 to 89 years(P <.001). Overall improvements in 6MW performance were found in both white subjects (n = 575; P <.001) and African-Americans (n = 54; P <.001). There were no apparent relationships between 6MW performance and overall or Health and Function QOLI scores (r <.21). Conclusions: Participation in short-term outpatient CR improved 6MW performance in patients aged 40 to 89 years across 14 programs in North Carolina. No relationships were found between 6MW performance and any domain of the QOLI, including the Health and Function domain. (Heart Lung® 2003;32:41-51.)

Section snippets

Subjects

The subjects for this investigation consisted of 424 men and 206 women aged 40 to 89 years from 14 North Carolina early outpatient (Phase II) CR programs. Patients were tested between January 1, 1997, and December 31, 2000. Only those patients who completed both the initial and follow-up test procedures were included in this study. Patient age, diagnosis, and ethnicity were typical for North Carolina CR programs (Table II).

. Descriptive characteristics of the sample (N = 630)

Variablen (%)
Gender
 

Six-minute walk

Six-minute walk distance increased for all patients in all age categories across programs after multidisciplinary CR (P <.0001) (Table III).Men walked farther than women on both the initial and follow-up 6MW tests (P <.0001). Although both sexes showed a statistically significant improvements in 6MW distance after CR, men showed a greater overall improvement in walking distance.

Tukey post-hoc analyses showed that there were statistical differences in 6MW performance between specific age groups

Discussion

Timed walking tests have become increasingly popular for quantification of physical function and activity status for patients in CR programs. This popularity results from many factors, one being that CR staff are now more accepting of entering participants without having the results of a symptom-limited graded exercise test. Both timed walking tests and graded exercise tests have limitations because test validity is often hindered by (1) lack of metabolic analysis, (2) treadmill handrail

Limitations

There are some important limitations of this investigation that warrant attention. First, this was a prospective, nonrandomized study. We did not include a control group of patients who did not participate in CR for comparative purposes. For a study of this nature, it was nearly impossible to randomize participants from different programs or to develop a control group of nonparticipating CR patients because we had no control of who entered and who did not enter CR programs from different cities

Clinical implications

The process of measuring outcomes, benchmarking results, and using this information to verify the importance of CR intervention will be critical for the success of CR programs in the 21st century. Collecting patient and program outcomes is recommended by both the AACVPR1 and the Joint Commission on the Accreditation of Hospital Organizations. This information, when collected, analyzed, and reported, documents the progress of patient as well as overall program effectiveness. This study from the

Conclusions

The following conclusions can be drawn from this ongoing NCCRA investigation:

  • 1.

    Men and women from multiple outpatient CR programs improved 6MW performance across all age categories after short-term CR intervention.

  • 2.

    Men walked longer 6MW distances before and after CR intervention than women in all age groups.

  • 3.

    There were no significant relationships observed between 6MW performance and any domain of the Ferrans and Powers QOLI, in particular the Health and Function subscale.

Additional study of 6MW

Acknowledgements

The authors thank the members of the NCCRA for taking the time and effort to measure, quantify, and submit data for this ongoing investigation. We also thank Dr. Carl King, Dr. Derek McEntee, and Dr. Carol Ferrans for their efforts in the development and refinement of a tool to quantify scores on the Ferrans and Powers QOLI for everyday use in cardiac and pulmonary rehabilitation programs across the country.

References (53)

  • DR Southard et al.

    Outcomes as a management tool

    J Cardiopulm Rehabil

    (1999)
  • LK Hall

    Will my cardiac rehabilitation program survive in the new managed-care era? The road map will be drawn by measuring outcomes

    J Cardiopulmon Rehabil

    (1998)
  • P Pashkow et al.

    Outcome measurement in cardiac and pulmonary rehabilitation

    J Cardiopulm Rehabil

    (1995)
  • JS Jungbauer et al.

    Feasibility of a multi-state outcomes program for cardiopulmonary rehabilitation

    J Cardiopulm Rehabil

    (1999)
  • GJ Balady et al.

    Changes in exercise capacity following cardiac rehabilitation in patients stratified according to age and gender—Results of the Massachusetts Association of Cardiovascular and Pulmonary Rehabilitation multicenter database

    J Cardiopulm Rehabil

    (1996)
  • D Verrill et al.

    Quality of life measures and gender comparisons in North Carolina cardiac rehabilitation programs

    J Cardiopulm Rehabil

    (2001)
  • DM Hamilton et al.

    Validity and reliability of the 6-minute walk test in a cardiac rehabilitation population

    J Cardiopulm Rehabil

    (2000)
  • GH Guyatt et al.

    The six-minute walk: a new measure of exercise capacity in patients with chronic heart failure

    Can Med Assoc J

    (1985)
  • V Bittner et al.

    Prediction of mortality and morbidity with a 6-minute walk test in patients with left ventricular dysfunction

    JAMA

    (1993)
  • V Bittner et al.

    Assessing functional capacity as an outcome in cardiac rehabilitation: role of the 6 minute walk test

    Clin Exerc Physiol

    (2000)
  • B Steele

    Timed walking tests of exercise capacity in chronic cardiopulmonary illness

    J Cardiopulm Rehabil

    (1996)
  • WG Herbert et al.

    Usefulness of the timed walking test: an alternative to the GXT in cardiac rehabilitation

    (2002)
  • WJ Gibbons et al.

    Reference values for a multiple repetition 6-minute walk test in healthy adults older than 20 years

    J Cardiopulm Rehabil

    (2001)
  • PL Enright et al.

    Reference equations for the 6-minute walk in healthy adults

    Am J Respir Crit Care Med

    (1998)
  • R Benzo et al.

    Effect of pulmonary rehabilitation on quality of life in patients with COPD: The use of SF-36 summary scores as outcomes measures

    J Cardiopulm Rehabil

    (2000)
  • MC Haggerty et al.

    Functional status in pulmonary rehabilitation patients

    J Cardiopulm Rehabil

    (1999)

    • Cited by (0)

    *

    Reprint requests: David Verrill, MS, RCEP, FAACVPR, Presbyterian Pulmonary Health and Rehabilitation Program, 125 Baldwin Ave, Ste 200, Charlotte, NC 28204.

    **

    0147-9563/2003/$30.00 + 0

    View full text
    Copyright © 2003 Published by Mosby, Inc.