FRIDAY, March 30, 2012 (HealthDay News) -- Dietary factors and cigarette smoking may alter the course of disease in patients with a milder form of multiple sclerosis, a new study finds.
Out of nearly 900 patients with what is called "relapsing onset" multiple sclerosis (MS), those who regularly consumed alcohol, caffeine and fish were less likely to progress to the point that they needed help walking, which is considered a milestone in the course of the disease. In contrast, cigarette smoking was associated with an increased risk of becoming disabled.
One explanation is that dietary factors might have a direct protective effect on MS patients, said Dr. Marie D'hooghe, a clinical neurologist in Belgium and lead author of the study. Caffeine, fish and alcohol at low to moderate levels are all known to have anti-inflammatory properties, and focal, or localized, inflammation in the brain and spinal cord is an important aspect of relapsing MS.
However, the study did not prove that caffeine and alcohol will slow MS, an incurable disease of the nervous system, and patients should not use these findings as a reason to suddenly start brewing coffee and sipping cocktails.
Also, the study only saw the associations between diet and smoking and disease progression among patients with relapsing-remitting MS, and not among those with what is known as primary progressive MS.
This suggests that progressive MS is a distinct phase of the disease with different mechanisms, D'hooghe said. "Degeneration [of nerve cells] is probably more relevant in progressive onset and inflammation is not as important," she said.
MS affects more than 350,000 people in the United States and about 2.5 million worldwide. Most patients experience relapsing-remitting MS, which has a variable disease course involving alternating attacks and recovery periods, while about 15 percent of patients have primary progressive MS, marked by a steady worsening of the disease.
The new study is published in the April issue of the European Journal of Neurology.
For the study, researchers mailed questionnaires to patients registered with the Flemish MS Society, asking about their consumption of alcohol, wine, coffee, tea and fish, as well as about cigarette smoking.
The questionnaires also asked patients about their disease (relapsing or progressive), and whether they had reached the stage that they needed a cane or other support to walk about 330 feet, and if so, how long after disease diagnosis they reached that point.
The study included almost 1,400 participants, about 900 with relapsing-remitting MS and almost 500 with primary progressive MS. They were between 17 and 89 years of age.
Researchers found that the association between delayed disease progression and consumption of alcohol, caffeine and fish among relapsing MS patients was stronger for patients with greater consumption.
For example, patients who did not consume any alcohol took about 25 years to progress to the stage of disease where they needed support to walk. However, those who had either less than one drink or at least one alcoholic drink per week reached this stage at around 28 and 32 years, respectively.
In contrast, smoking appeared to accelerate disease progression. Smoking is known to be a risk factor for developing MS, and could also play a role in disease progression, D'hooghe said.
Still, it remains possible that diet and smoking do not affect the disease's course, D'hooghe noted. Instead, people who drink alcohol and caffeine and eat fish might be more likely to make other lifestyle or diet choices that affect the disease.
Another possibility, D'hooghe added, is that the MS patients who are able to enjoy a glass of wine or go out to buy fish are also the ones who have less advanced disease.
But even if dietary factors are not helpful against disease, this study suggests that low to moderate consumption might also not be harmful. "At least we have no argument for an adverse effect," D'hooghe said.
Another expert said it is tricky to know what the findings mean for patients.
Dr. Bianca Weinstock-Guttman, a neurologist at State University of New York at Buffalo, suggested that patients talk with their doctors about whether drinking alcohol might interfere with their medications and about the possibility that drinking caffeine could aggravate bladder problems that are common in MS.
While these dietary components could help early in the course of relapsing MS, it is very difficult to have a clear-cut benefit in the later stages of the disease or in the case of primary progressive MS, said Weinstock-Guttman.
To learn more about multiple sclerosis, head to the National MS Society.