Hypertension Quite Common Among MS Patients in US, Study Finds
High blood pressure was found to be 42% more common among MS patients than non-patients adjusted for sex and age, with male patients ages 70 and older most at risk. Its prevalence was 25% higher among patients than others when adjusting for race, with Blacks with MS more likely to be affected than whites, the researchers found.
Their study, “The prevalence of hypertension in multiple sclerosis based on 37 million electronic health records from the United States,” was published in the European Journal of Neurology.
Hypertension is a common comorbidity (co-occurring condition) in MS patients, and it is frequently associated with poorer outcomes for patients.
However, its prevalence among people with MS has not been well characterized, with an occurrence reported to range between 0 and 47.8%.
Other studies report contradictory results.
A team at Case Western Reserve University led an extensive study of the American population to better assess the prevalence of hypertension in people with MS.
It analyzed electronic health records from the IBM Explorys Enterprise Performance Management: Explore database (Explorys), a multi-institutional database covering 63 million people in the U.S.
In total, data on 122,660 MS patients (MS group) were analyzed, and compared with data on 37.1 million people without the disease (non-MS group). All were matched by age, sex, and race.
Results showed a significantly greater prevalence of hypertension among MS patients when compared with the non-MS group across ages, sexes, and races.
“The crude prevalence of HTN was 41.5% and 22.7% in the MS and non-MS cohort, respectively. This corresponds to an 82% higher prevalence of HTN in [MS patients] compared to non-MS individuals,” the researchers wrote.
The team then analyzed adjusted prevalence estimates according to age, sex, and race-specific factors.
With adjustments for age and sex, hypertension was 42% more common among patients than non-patients, and 25% more common among patients adjusting for race (Black and white Americans).
“These results emphasize the importance of appropriately adjusting for key demographics in generating comorbidity prevalence estimates related to MS,” the researchers wrote.
In both the MS and non-MS groups, a gradual increase in hypertension’s prevalence was evident with advancing age. Among MS patients, hypertension exceeded 65% starting with people in the 70–74 age group, while among those without MS it did not exceed 60.5% for any age group.
Hypertension was also more prevalent among Black Americans (28.9%) that whites (26.2%), and more prevalent in patients across both these racial groups than in those without the disease. Black MS patients also had a “notably higher burden of HTN” starting at ages 75–79 than did white patients.
The researchers could not clearly identify why Black Americans have this higher prevalence.
“It is likely due to a combination of population differences (e.g., differences in vascular resistance, endothelial vasodilation, response to antihypertensive medications) and social determinants of health (e.g., differences in healthy food access, perceived neighborhood safety, access to health resources),” they suggested.
Researchers also observed a higher prevalence of hypertension in males (24.1%) than females (21.5%) for both MS and non-MS groups. They suggested this was because “compared to males, females tend to have higher rates of awareness, treatment, and control of HTN. Additionally, estrogen is known to decrease blood pressure.”
Overall, data demonstrated that hypertension “is significantly more common in the MS population compared to the non‐MS population, irrespective of sex and race,” the researchers wrote.
Several factors may be behind this greater prevalence.
“Like HTN, MS is associated with obesity, lower socioeconomic status, tobacco smoking, and physical inactivity as a result of disability accrual,” the researchers suggested. “Additionally, there is some evidence that HTN might be a side effect of pharmacological treatment for MS.”
Since hypertension is a major global risk factor for greater disability and death, and for greater loss of ambulation and depression among MS patients specifically, these results highlight the need for a comprehensive approach in managing hypertension in the MS population, the team wrote.
Furthermore, “future research should explore the impact of HTN on cognitive outcomes [and] response to disease-modifying therapies,” the researchers suggested. “Also, there is a need to understand the directionality of the association between MS and HTN.”