ABSTRACT
PURPOSE: Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease; however, no study has evaluated the influence of vitamin D status on effects of pulmonary rehabilitation (PR). METHODS: We studied 311 patients, who participated in a 7-week outpatient PR. Vitamin D status was assessed at entry and examined for association with patient characteristics, dropout from PR, and effect on endurance shuttle walk time. RESULTS: Vitamin D level 25 nM was seen in 61 (19.6%) of the patients. They were significantly younger, were more frequently on long-term oxygen therapy, had higher body mass index and fat-free mass index, had worse quality of life score, tended to have lower percent predicted value for forced expiratory volume in the first second of expiration, and more frequently were current smokers. They had a 3-time higher risk of dropout from the PR program (P = .003) compared with patients with normal vitamin D status and a poorer improvement in endurance shuttle walk time (P = .03). DISCUSSION: In conclusion, vitamin D deficiency was significantly associated with higher dropout rates from PR, and there was a tendency toward a poorer improvement in endurance shuttle walk time.
Subject(s)
Patient Participation/psychology , Pulmonary Disease, Chronic Obstructive/rehabilitation , Vitamin D Deficiency/diagnosis , Vitamin D/analogs & derivatives , Aged , Confidence Intervals , Exercise Test , Female , Forced Expiratory Volume , Health Status Indicators , Health Surveys , Humans , Linear Models , Logistic Models , Male , Odds Ratio , Outpatients , Pulmonary Disease, Chronic Obstructive/blood , Pulmonary Disease, Chronic Obstructive/psychology , Statistics as Topic , Statistics, Nonparametric , Surveys and Questionnaires , Vital Capacity , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/pathologyABSTRACT
BACKGROUND: The Incremental Shuttle Walking Test (ISWT) is used to assess exercise capacity in chronic obstructive pulmonary disease (COPD) and is employed as an outcome measure for pulmonary rehabilitation. We studied the value of this test in predicting survival in COPD patients enrolled in a rehabilitation program. METHODS: A total of 416 patients performed an ISWT before entering a 7-week outpatient pulmonary rehabilitation program. Their survival was observed over a mean period of 4.5 years (range = 1.2-7.2 years). RESULTS: During the observation period, 169 (40.6%) patients died. Univariate analyses showed that the ISWT as well as age, gender, present and previous tobacco smoking, forced expiratory volume in 1 second, body mass index, oxygen saturation at rest, long-term oxygen therapy, Medical Research Council dyspnea score, and treatment with oral corticosteroids were significantly associated with survival. Multivariate analysis, including relevant confounders, revealed that low ISWT was independently associated with poor survival (P = .001). The association was not linear and the risk of dying increased markedly when ISWT was lower than 170 m (RR = 2.84, 95% CI: 2.05-3.93). CONCLUSION: This study shows that the ISWT is a strong and independent predictor of survival in patients with COPD enrolled in a rehabilitation program.
Subject(s)
Exercise Test , Pulmonary Disease, Chronic Obstructive/mortality , Walking/physiology , Aged , Body Mass Index , Confidence Intervals , Female , Forced Expiratory Volume , Humans , Male , Multivariate Analysis , Outpatients , Oxygen Consumption , Prognosis , Program Evaluation , Proportional Hazards Models , Pulmonary Disease, Chronic Obstructive/rehabilitation , Risk , Risk Factors , Survival Analysis , Treatment Outcome , United KingdomABSTRACT
PURPOSE: To examine whether maintenance training (MT) for 1 year improved the long-term effects of a 7-week chronic obstructive pulmonary disease (COPD) rehabilitation program. METHODS: After a 7-week outpatient rehabilitation program, 96 patients with COPD were randomized to either an MT group (n = 55) or a control group (n = 41). Both groups were requested to continue unsupervised training at home. The MT group received weekly supervised training the first 6 months, supervised training every second week the next 6 months, and finally no supervised training the last 6 months of the 18-month study period. Primary effect parameters were Endurance Shuttle Walk Test (ESWT) time and health status (St. George's Respiratory Questionnaire, SGRQ). Secondary effect parameters were adherence to supervised training, dropout rates, and hospitalization. RESULTS: Compared with the control group, the MT group had significantly better ESWT times at 3 and 6 months (+43.9 seconds; P= .03, and +75.1 seconds; P= .02) and insignificantly higher ESWT time at 12 months (+66.6 seconds; P= .40). SGRQ total score declined gradually after the 7-week program with no difference between the 2 groups, and after 18 months, the score was 1.7 units (95% confidence interval: -0.7 to 4.1) worse than at randomization. There was no difference between the 2 groups regarding dropout rates or hospitalization. DISCUSSION: Weekly MT for 12 months improved walking time but had no influence on health-related quality of life or hospital admissions, compared with unsupervised daily training at home. The effect of the MT was closely related to adherence to the program.
