On matters of diet, nutrition and weight in ALS

There has been much debate regarding the role of diet and various nutrients in altering the course of ALS. In today’s plenary on Nutritional Assessment and Management researchers researchers aimed to answer some of these questions. Dr. Gennings (USA) opened the session with the talk on the relationship between different types of nutrients and physical function in ALS. Preliminary cross-sectional data from the COSMOS study suggests that micronutrients such as omega, selenium, vitamin E and vitamin K are associated with higher ALSFRS-R and FVC, while foods such as milk and cheese with lower. Due to the cross-sectional data the causal relationships could not be inferred, but it is hoped that the longitudinal data which is currently being collected will provide us with more definitive answers.

It is well known that patients with ALS are at an increased risk of malnutrition due to feeding problems. Dr. Stavroulakis (UK) examined the usefulness and safety of gastrostomy in ALS in an observational study. Main indications for gastrostomy were  difficult meals, unsafe swallowing, weight loss and recurrent aspiration. 30 day mortality after the procedure was significantly higher in patients with preceding weight loss of more than 10% and suggested that gastrostomy should be considered earlier. Although the main benefits of gastrostomy perceived by the clinicians were nutritional stabilisation, half of the patients continued to loose weight despite the intervention. Nonetheless, 60% of patients maintained or improved their quality of life although this was at the expense of the carer burden.

Early identification of patients with potential swallowing problems is important to avoid serious complications such as aspiration pneumonia. Dr. Plowman (USA) reported reliable tools assessing swallowing problems, which can be completed by a patient or carer. There was a high correlation with pharyngeal muscle dysfunction and risk of aspiration confirming validity of the tools. Combining this with the results from gastrostomy study described above, we might be able to detect swallowing problems and treat them to prevent serious complications.

And finally, one would struggle to argue for the benefits of obesity to health unless we are talking about ALS patients. Dr. Rudnicki (USA) hypothesised that patients with higher BMI may have a survival advantage. Indeed, the results of retrospective study showed that premorbid obesity and slower decrease in BMI after diagnosis of ALS is associated with longer survival. Clearly, a randomised controlled trial is needed to evaluate the role of aggressive nutrition on survival in ALS.