Background and purpose: We assessed the prevalence and potential association of hypertension with multiple sclerosis (MS)-related disability progression.
Methods: This was a retrospective study of 2,813 patients who were followed for 20 years. We modeled the associations of several risk factors with the pattern of disability progression. The primary end point was the rate of disability progression.
Results: In total, 2,396 patients were available for analysis, of which 1,074 (44.8%) scored 4 (EDSS4) on the Expanded Disability Status Scale (EDSS), 717 (29.9%) scored 6 (EDSS6), and 261 (10.9%) scored 8 (EDSS8). The mean times to reach scores of 4, 6, and 8 were 123.5, 163.1, and 218.9 months, respectively. Hypertension was present in 207 (8.6%) patients during follow-up. Hypertension was associated with a higher probability of reaching each EDSS score compared to non-hypertensive patients: 62% vs. 43% for EDSS4 (p<0.01), 51% vs. 28% for EDSS6 (p<0.01), and 17% vs. 10% for EDSS8 (p<0.01). Nevertheless, hypertensive MS patients experienced longer intervals to reach each EDSS score: longer by 51.6, 38.9, and 62.7 months to EDSS4, EDSS6, and EDSS8, respectively (p<0.01) when compared to non-hypertensive MS patients reaching the same EDSS scores.
Conclusions: Disability progression is more prevalent amongst hypertensive MS patients. However, they experience longer time intervals between the stages of disability progression.
Keywords: atherosclerosis; disability; epidemiology; hypertension; multiple sclerosis; risk factor.