Several experts presented their views of best practices for care of people with ALS at MDA's 2012 Clinical Conference, held in Las Vegas March 4-7.
Best practices outlined in this article include:
- the new diaphragm pacing system;
- nutrition and weight in ALS; and
- the value of supportive care.
'Jury still out' on diaphragm pacing in ALS
Robert Miller, a neurologist who co-directs the MDA/ALS Center at California Pacific Medical Center in San Francisco, discussed the use of the recently developed diaphragm pacing system in ALS.
The NeuRx Diaphragm Pacing System delivers rhythmic electrical signals to the respiratory diaphragm. It has to be inserted surgically. Illustration courtesy of Synapse Biomedical
Miller noted that:
- The NeuRx Diaphragm Pacing System, which electronically stimulates the diaphragm to aid breathing, has received approval from the U.S. Food and Drug Administration (FDA) for humanitarian use in ALS. (This designation means that the FDA believes the probable benefit to health outweighs the risk of injury or illness from use of the device.)
- Data suggest the DPS offers a possible survival benefit to those with ALS, but its effectiveness has not been proven.
- Studies of the DPS in ALS are continuing. The "jury is still out" on whether the device is effective for ALS-related respiratory problems.
Lack of consensus on deliberate weight gain in ALS
Anne-Marie Wills, a neurologist and public health specialist from Massachusetts General Hospital in Boston, presented data on nutrition and weight in ALS.
Wills has previously found that people with ALS who are overweight or moderately obese survive longer than those who are underweight, normal weight or morbidly obese.
Results are expected soon from Wills' MDA-supported study of whether a high-fat, high-calorie diet is superior to a regular diet in ALS.
- Moderate obesity is associated with increased survival time in ALS and therefore may be desirable for people with this disease.
- It isn't clear whether weight loss in ALS, which is associated with shorter survival time, is itself causing people to deteriorate faster or is merely a marker of faster disease progression.
- Conversely, it also isn't clear whether weight maintenance or weight gain in ALS, which is associated with longer survival time, is itself causing people to survive longer or is merely a marker of slower disease progression.
- New data suggest people with ALS do not have a particularly high metabolic rate, something that had previously been suspected. In fact, some may have a low metabolic rate.
- A measurement called total energy expenditure is a poor predictor of caloric needs in ALS.
- Malabsorption (less than optimal passage of nutrients from the gastrointestinal tract into the bloodstream) may be responsible for some ALS-associated weight loss.
- There is no consensus among dieticians on whether or not people with ALS should purposely gain weight. Wills said 40 percent of dieticians surveyed recommended weight gain for people with ALS; 40 percent recommended weight stabilization; and 20 percent said weight loss was all right.
Supportive care may be increasing survival time in ALS
Neurologist Ericka Simpson, co-director of the MDA Clinic at Methodist Neurological Institute in Houston, discussed the "changing natural history of ALS." (Natural history refers to the course of the disease.)
- People with ALS are, on average, declining less rapidly and living longer with the disease than in the past.
- ALS — amyotrophic lateral sclerosis — should now be thought of in the plural, as amyotrophic lateral scleroses, reflecting the large number of subtypes of the disease that are now recognized and the great variability among subtypes.
- Five to 10 percent of people with ALS live more than 10 years.
- It is not known whether longer survival and slower progression are a result of relatively recent improvements in supportive care or a change in the disease itself or some combination of these factors.
- Supportive care in ALS now includes routine use of noninvasive ventilation to support breathing and feeding tube insertion to support nutrition.