Higher Risk of Vascular Disease Among MS Patients in the UK, Population-based Study Reveals

People in the United Kingdom (U.K.) with multiple sclerosis (MS) have an increased risk of vascular disease affecting the heart and brain that is not accounted for by traditional disease risk factors, a large, population-based study reports. 

The study, “Evaluating the Risk of Macrovascular Events and Mortality Among People With Multiple Sclerosis in England,” was published in the journal JAMA Neurology.  

Compared with the general population, people with MS can have higher blood pressure and increased levels of fat (lipids) in their blood, are overweight, and engage in less physical activity. 

As such, people with MS may be at risk for cardiovascular disease leading to heart attack and stroke. 

However, most studies investigating this link are not based on the general population, while others did not account for lifestyle factors or were conducted before recent advances in available treatments for MS and cardiovascular disease. 

To better understand the current cardiovascular disease risks in MS patients, a team led by researchers at the Imperial College of London and the University College London in the U.K. analyzed the medical records of 12,251 people with MS, diagnosed between January 1987 and September 2018, who were representative of the English population. 

The team looked for outcomes including reduced blood flow to the heart (acute coronary syndrome), vascular disease of the brain (cerebrovascular), and disease of any large blood vessels like the arteries of the heart and the brain (macrovascular). Information on death by any cause (all-cause mortality) and cardiovascular disease-specific mortality also was collected.

Demographic information covering age, sex, ethnicity, smoking status, diagnosis of type 2 diabetes and clinical depression, or the use of cardiovascular disease-related medications also was gathered. As a comparison, clinical data were obtained from the medical records of 72,572 people without MS or related conditions who were similar in age and sex to the MS group analyzed. 

Among those with MS, the mean age was 45 years, 66.9% were women, and the average follow-up time was 10.3 years.

The results were calculated in person years — a measurement representing the number of patients multiplied by the number of years patients have a condition. 

The analysis revealed that MS patients had an incidence of acute coronary syndrome of 204.5 events per 100,000 person years, compared to 116.8 for control subjects. Likewise, people with MS had a higher incidence of cerebrovascular disease (159.6 vs. 81.4 in controls), and macrovascular events (291.8 vs. 159.1).

Interestingly, these differences were more predominant in women with MS vs. those without, compared to men. 

The mortality rate for people with MS was 2,222.3 events per 100,000 person years compared to 619.5 events for controls. 

Overall, those with MS had an almost 3.5 times higher risk of all-cause mortality and about 1.5 times higher risk of cardiovascular disease-related mortality compared to controls. The increased all-cause mortality risk for women was slightly higher than for men — 3.5 times versus 2.7 times in men. 

A comparison of those taking medications to reduce blood lipids — such as statins — to prevent cardiovascular disease, which represented about 3% of the study population, found that people with MS who were taking these medicines had a lower risk of all-cause mortality. They also had and an increased risk of cardiovascular disease mortality compared to patients not taking them. 

MS patients taking these medicines had mortality rates two times higher compared with controls not taking these lipid-lowering medications; while those with MS not using these medications had a 3.6 times higher mortality rate over control subjects. No differences between women and men were identified. 

An additional analysis investigated MS patients who were diagnosed after 2002 when the new MRI-based McDonald Criteria diagnostic criteria were implemented. Overall, most findings from this smaller analysis were consistent with the full study, and confirmed that the differences seen were less pronounced among men than in women with MS.

Overall, “this study suggests that MS is associated with an increased risk of cardiovascular and cerebrovascular disease that is not completely accounted for by traditional vascular risk factors,” the researchers wrote. 

“Given the adverse effects of these comorbidities [co-occuring conditions] on outcomes in patients with MS, further investigation is needed,” they added.