Energy expenditure and substrate utilization in adults with cystic fibrosis and diabetes mellitus.
BACKGROUND
The onset of cystic fibrosis-related diabetes mellitus (CFDM) is often associated with a decline in clinical and nutritional status.


OBJECTIVE
The purpose of this study was to characterize energy expenditure (EE) and substrate utilization during rest, exercise, and recovery from exercise in patients with CF diagnosed with diabetes mellitus.


METHODS
EE, substrate utilization, minute ventilation, tidal volume, and respiratory rate were calculated by indirect calorimetry durng rest; a 30-min, low-to-medium-intensity exercise bout on a treadmill; and a 45-min postexercise recovery period (in reclining position) in 10 CF, 7 CFDM, and 10 control subjects between 18 and 45 y of age.


RESULTS
In all 3 periods, minute ventilation was higher in the CF and CFDM groups than in the control subjects (P < 0.01). During rest and exercise, the CF and CFDM groups maintained EE values at the high end of the normal range of the control subjects. However, during recovery, EE was higher in the CF and CFDM groups than in the control group (P < 0.01).


CONCLUSIONS
EE may be higher than usual for the patients with CF and CFDM during periods of recovery from mild exercise or activity because of increased work of breathing consistent with higher ventilatory requirements. This information may be useful for patients receiving nutritional counseling who may choose to exercise regularly, but are concerned about possible weight loss.
Ward
S A
SA
Pediatric Pulmonary Center, Hahnemann University Hospital, Philadelphia, USA. sward@vger.nsu.edu
Tomezsko
J L
JL
Holsclaw
D S
DS
Paolone
A M
AM
D000328:Adult; D001823:Body Composition; D003550:Cystic Fibrosis / Q000150:complications / Q000378:metabolism*; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000378:metabolism*; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise; D006801:Humans; D009752:Nutritional Status; D010101:Oxygen Consumption; D012129:Respiratory Function Tests; D012146:Rest; D014939:Work of Breathing