O6.6 Nutrition

In patients with COPD, both excess and low weight is associated with increased morbidity. Obesity increases the work of breathing and predisposes to sleep apnoea — both central hypoventilation and upper-airway obstruction. Progressive weight loss or body mass index < 20 are important prognostic factors for poor survival (Gray-Donald et al., 1996),(Schols et al., 1998),(Ferreira et al., 2005) [evidence level I]. This may be the result of a relative catabolic state (related to high energy demands of increased work of breathing) added to disturbance of nutritional intake (related to breathlessness while eating). Deleterious consequences include combined protein–energy malnutri­tion,(Schols et al., 1998) and possibly mineral or essential vitamin and anti­oxidant deficiencies.(Schols et al., 1998)

Randomised controlled trials of nutritional support in COPD have not shown significant improvements in nutri­tion, exercise capacity or other outcomes(Ferreira et al., 2005) [evidence level I]. However one recent unblinded RCT of 66 nutritionally at risk patients with a mean BMI of 19.7 kg/m2 found that the combination of dietary counselling and food fortification was associated with significantly improved quality of life and dyspnoea scores (Weekes et al., 2009) [evidence level II]. Patients with COPD should not eat large meals, as this can increase dyspnoea. Several small nutritious (high energy, high protein) meals are better tolerated. Snacks may provide a useful addition to energy and nutrient intake. Referral to a dietitian for individual advice may be beneficial.

Anabolic steroids in patients with COPD with weight loss increase body weight and lean body mass but have little or no effect on exercise capacity. (Yeh et al., 2002), (Weisberg et al., 2002)