Nutrition and diet
Optimum nutrition is crucial as part of the overall treatment plan for patients with bronchiectasis. Nourishing foods and fluids provide the body with the energy (kilojoules or calories), macronutrients (protein, fat and carbohydrate) and micronutrients (vitamins and minerals) for the body’s needs including the increased work of breathing associated with the condition.
Ideally, all patients with bronchiectasis should receive individualised nutritional education and counseling by a qualified dietitian (see box below) as part of their overall therapy to maintain or achieve a normal nutritional state. This may be through the optimisation of their diet and assessing the need for oral nutritional supplementation or enteral nutrition if energy and protein deficits are apparent, and cannot be met by diet or food fortification especially during times of exacerbations.
Finding a qualified dietitian:
Dietitians work in a wide variety of settings, helping people to improve their health & lifestyle through optimal nutrition. Dietitians provide specialist services in hospitals, community health centres, private practices, aged care facilities and other settings.
A qualified dietitian assesses the patient’s global nutrition status and nutrition risk factors by considering weight and body mass index, history of weight loss or weight gain; and assessing food intake to determine nutritional adequacy, factors influencing food intake such as appetite and other symptoms such as breathlessness, food intolerances or restrictions, health status and practical influences on shopping, food preparation or intake. They may also consider body composition (the proportion of muscle and fat in the body); results of blood and other tests; exercise levels and medications. They use this information to identify if dietary changes are required and if so, to develop a plan in conjunction with the patient to address the identified nutrition issues.
Classification of weight status: adults
In adults, weight status is classified using the Body Mass Index (BMI), which is calculated by dividing weight by the square of height: BMI (kg/m2) = Weight(kg) ÷ Height (m) squared
Weight = 70kg, height = 1.72m
Height squared = 2.96.
BMI = 70 / 2.96 = 23.6 kg/m2
As defined by the World Health Organisation, a normal BMI for adults is traditionally classified between the range 18.5kg/m2 to 24.99kg/m2, while overweight is a BMI between 25.00-29.99kg/m2 and >30.00kg/m2 is classified as obese. A BMI of <18.5kg/m2 is classified as underweight. Being underweight increases the risk of morbidity and mortality.
More recently, evidence has emerged that these WHO cut-offs may not be appropriate in older adults (>65 years). The relationship between BMI and mortality is different in older adult populations, with mortality risk lowest at BMI 24-31kg/m2. Older adults face a higher risk of undernutrition and sarcopaenia (loss of muscle mass and function with ageing).
Whilst the BMI is useful for classifying weight status, it has some limitations, including that it does not distinguish fat mass from muscle mass; and thus assessment of body composition may be useful to augment the information provided by weight and BMI. Simple body composition measures include circumferences (waist, mid-arm); skinfold thickness measurements, whilst more sophisticated techniques include bioelectrical impedance and dual-energy X-ray absorptiometry. There are not yet any published reference ranges for body composition measurements specific to bronchiectasis, but sequential monitoring over time may help clinicians to interpret the tissue composition of weight gained or lost (intentionally or unintentionally). Adapted from WHO, 1995, WHO, 2000 and WHO 2004 and Australian and New Zealand Society for Geriatric Medicine, Position Statement No. 19: Obesity and the Older Person
Assessment of growth and weight – children
Children with acute and chronic illnesses face a risk of suboptimal growth and weight gain. Routine measurement of height and weight, and plotting on the growth chart used locally, play an important role in the early detection and management of nutrition and growth deficits. Further information on the use of both the CDC and WHO growth charts is available at this link.
Underweight and unintentional weight loss
Patients with bronchiectasis may present underweight and/or with malnutrition, which impacts on lung function, immune function, physical function and strength. Energy (kilojoule, calorie) requirements are increased in people with bronchiectasis due to increased work of breathing, chronic inflammation and infection. This, coupled with reduced appetite (anorexia), breathlessness and general fatigue, increases the risk of weight loss (particularly loss of muscle mass. Where infections are severe and/or frequent, a vicious cycle of recurrent and progressive weight loss can occur. If weight and muscle mass are not regained in between, malnutrition may is likely to evolve, which in turn increases the risk of infection. Malnutrition is associated with higher mortality; longer and more frequent hospitalisations and increased health care costs (Australian and New Zealand Society for Geriatric Medicine, Position Statement No. 6: Undernutrition and the Older Person).
It is important to recognise that it is not only underweight individuals who are at risk of malnutrition. Unintentional weight loss is a risk for the development of malnutrition, even in patients who are of normal weight or even overweight. Weight should be regularly monitored so that unintentional weight loss is identified early.
Inadequate nutritional intake, infection and increased work of breathing can individually or collectively contribute to negative energy balance resulting in unintentional weight loss and increased malnutrition risk. Nutrition support interventions for bronchiectasis patients who are underweight, losing weight, or at risk of malnutrition include:
Eating frequent nutrient dense (high energy, high protein) meals and snacks. During hospital admissions, availability of between-meal snacks and nourishing drinks is particularly important for meeting nutrition requirements when appetite is impaired.
Food fortification strategies
When dyspnoea or fatigue are issues, choose softer foods that are less effortful to chew or swallow
Use of nutrient dense drinks (home-prepared milk-based drinks and/or oral nutritional supplements)
For some individuals, these strategies are required only during infection or exacerbation or as part of recovery; while others require nutrition support strategies on a longer-term basis. Patients unable to meet nutrition requirements with oral nutrition support should be considered for enteral nutrition (for example, supplementary feeding via a gastrostomy tube.
Being overweight or obese increases the pressure on the patient’s heart and lungs to supply oxygen. Being overweight also increases the risk of developing diabetes, heart disease and some cancers and can impair mobility. Intentional weight loss through a healthy diet and exercise may reduce the increased work of breathing linked to an increased BMI. In the presence of obesity or increased BMI, a weight loss goal can be set, aiming to reduce fat mass whilst preserving muscle mass. Aim for 0.5-1.0kg/week and monitor carefully for unintentional weight loss and/or loss of muscle mass. More rapid weight loss is associated with higher risk of muscle mass loss and nutrient inadequacy. Weight loss can be achieved through kilojoule (calorie) restriction and an emphasis on healthy eating and an increase in energy expenditure through exercise/activity within the patient’s limits, and as guided by a physiotherapist or other suitably qualified professional with experience in chronic lung disease.
Other Nutritional Considerations
Adequate micronutrient status in people with bronchiectasis is important for the functioning of all organs. This can be achieved by enjoying a wide variety of nutritious foods from the five food groups outlined in the Australian Guide to Healthy Eating.
The five food groups are:
Bread, Cereal, Rice, Pasta, Noodles
Milk, Yoghurt, Cheese
Meat, Fish, Poultry, Eggs, Nuts, Legumes
There are no evidence-based recommendations that specific foods should be avoided by people with bronchiectasis. Unnecessary restriction of foods or food groups can increase the risk of weight loss or micronutrient inadequacy. A dietitian can discuss any nutritional concerns and give more detailed advice. The box above outlines how to find a dietitian in Australia or New Zealand.
If medications require the restriction of certain foods or drinks, this should be clearly indicated on the packaging, including specific considerations such as timing of intake. Further advice can be sought from a pharmacist; and a dietitian can provide guidance on how to maintain an adequate diet in periods of medication-related restrictions.
Reduced bone mineral density (osteoporosis and osteopaenia) are common in bronchiectasis. Refer to the Musculoskeletal issues section of this website for more information. Adequate calcium intake and vitamin D status are both important for maintaining bone density. In Australia, people receive most of their vitamin D from exposure of the skin to sunlight, rather than through the diet. Thus, people with limited sunlight exposure are at risk of vitamin D deficiency, and may require supplementation. For more information about vitamin D and osteoporosis, go to these links:
Adequate fluid intake is important for people with bronchiectasis to ensure secretions in the lungs are easy to expectorate. Thick and sticky secretions are often associated with dehydration and increase the risk of infection.
It is recommended to have at least 8 cups of fluid (non-alcoholic and non-caffeinated) per day e.g. water, milk, juice.