Depression, high blood pressure, other chronic conditions may be common at MS diagnosis

"These findings are interesting for several reasons," said study author Ruth Ann Marrie, MD, of the University of Manitoba in Winnipeg, Canada, and member of the American Academy of Neurology. "It raises the question of whether there are shared risk factors for both MS and these other diseases, and if so, whether we could eventually find ways to reduce the risk of both MS and the other diseases. Also, studies have shown that MS may progress faster for people who also have other chronic conditions, so it's important for people and their doctors to be aware of this and try to manage these conditions."

For the study, researchers examined how common several chronic conditions were in 23,382 people with MS at the time of their diagnosis and 116,638 people of the same age and sex without the disease. The conditions included high blood pressure, diabetes, high cholesterol, heart disease, chronic lung disease, epilepsy, fibromyalgia, inflammatory bowel disease, depression, anxiety, bipolar disorder and schizophrenia.

The people with MS had higher rates of all of the conditions except high cholesterol. The rates were especially high for mental illness. The most common condition was depression. At least 19 percent of those with MS had depression compared to 9 percent of those without the disease. As depression and anxiety can affect quality of life and can increase the risk of hospitalization, the ability of people to be adherent to their medication regimens is important. Marrie said these conditions should be closely monitored.

For many of the conditions, the rates differed for men and women with MS. For men with MS, the rate of high blood pressure was 48 percent higher than for men without the disease: 22 percent of men with MS versus 15 percent of men without MS. For women with MS, the rate was 16 percent higher than for women without the disease: 14 percent of women with MS versus 12 percent of women without MS.

Men with MS also had disproportionately higher levels of diabetes, epilepsy, depression and anxiety than women with MS. Women with MS had disproportionately higher levels of chronic lung disease than men with MS.

Marrie said further study is needed about the differences between men and women and whether the safety of MS treatments differs for those with additional chronic illnesses.

"One possible reason for the finding is that these chronic illnesses and MS share many of the same risk factors," said William B. Grant, PhD, of the Sunlight, Nutrition and Health Research Center in San Francisco, Calif., who wrote a corresponding editorial. "Smoking, obesity, low vitamin D and low omega-3 fatty acids have been shown to contribute to the severity of MS and, in various combinations, these other illnesses as well. Doctors will want to stress to those with MS the importance of correcting these problems."

It is important to note that the age of the people in the study when they were diagnosed was high and may not represent the MS population as a whole.

The researchers also looked at how common the conditions were five years before the people were diagnosed with MS and found that people who were later diagnosed with MS were still more likely to have the other conditions.