Cardiorespiratory fitness in relation to self-reported physical function in cancer patients after chemotherapy.
OBJECTIVE
The aim of this study was to estimate the association between objective cardiorespiratory fitness (CRF) and subjective self-reported physical function, taking into account the influence of mental distress. We hypothesized an association between these parameters, since they might be thought to measure parts of the same phenomenon.


METHODS
Approximately 1 month after discontinuation of all primary treatment, 90 cancer patients aged 18-50 years treated with chemotherapy were surveyed. CRF was determined by the Astrand-Ryhming indirect cycle ergometer test, which indicate peak VO2 in mL x kg(-1) x min(-1) (predicted VO2max). Self-reported physical function was assessed by The European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30). The relation between VO2max and self-reported physical function was estimated by multiple linear regression. Mental distress (assessed by The Hospital Anxiety and Depression scale), age, gender, body mass index (BMI), time from treatment to physical test and diagnoses were included as potential confounders.


RESULTS
There was no association between predicted VO2max and self-reported physical function. Mental distress was negatively associated with self-reported physical function (P<0.001), but is not associated with predicted VO2max.


CONCLUSIONS
The results suggest that predicted VO2max does not reflect self-reported physical function and vice versa in cancer patients after chemotherapy. If information about cardiac and/or pulmonary status is required, direct or indirect measures of VO2max should be used.
Thorsen
L
L
Department of Psychosocial Oncology and Rehabilitation, The Norwegian Radium Hospital, Oslo, Norway. lene.torsen@radiumhospitalet.no
Nystad
W
W
Stigum
H
H
Hjermstad
M
M
Oldervoll
L
L
Martinsen
E W
EW
Hornslien
K
K
Strømme
S B
SB
Dahl
A A
AA
Fosså
S D
SD
D000293:Adolescent; D000328:Adult; D000970:Antineoplastic Agents / Q000009:adverse effects*; D005080:Exercise Test; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D010101:Oxygen Consumption / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology* / Q000523:psychology; D011446:Prospective Studies; D013315:Stress, Psychological
D000970:Antineoplastic Agents