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Research showed that HSCT in MS was associated with long-term improvements in quality of life but may cause short-term cognitive decline post-treatment.

Hematopoietic stem cell transplantation (HSCT) appeared to be associated with improved quality of life (QOL) in people with multiple sclerosis (MS), but limited evidence suggests these benefits may come with a short-term cognitive decline after treatment, according to findings published in Multiple Sclerosis and Related Disorders.

“Research on HSCT in MS to date has predominantly focused on disease outcome measures, such as MRI activity and relapse rate, and physical disability symptoms,” researchers wrote. “Although neuropsychological symptoms such as fatigue, cognition, and mood can disproportionately impact MS patients’ quality of life, there is a dearth of research exploring neuropsychological outcomes following HSCT in people with MS.”

Important neuropsychologic factors to consider for these patients include mood, cognition, fatigue and QOL—all of which may be affected by HSCT, they continued.

Reviewing The Literature

The literature review included longitudinal studies reporting neuropsychologic outcomes in patients with MS who underwent HSCT. The goal of the study was to identify statistically significant changes in cognition, mood, fatigue, and QOL after receipt of stem cell therapy.

Among the 11 studies included, a major finding was that evidence regarding neuropsychologic effects of HSCT is quite limited.

Quality of life was the most studied neuropsychologic outcome. Others assessed were objective cognitive fatigue, subjective cognitive fatigue, objective cognitive function, and changes in mood.

Impact of HSCT on QOL, Mood, & Cognitive Function

Patients’ QOL improved after stem cell transplantation in all studies that included this outcome. Some found that QOL improvements were maintained for several years after treatment, with one study monitoring patients for up to 5 years, and others monitoring them for at least 2 years. Researchers wrote that the findings “consistently highlight long-term improvements in quality of life following HSCT in people with MS.”

Fatigue also appeared to be reduced after HSCT. Two studies found that fatigue measures improved both in patients with relapsing/remitting and those with progressive MS. These effects were not immediately apparent in one study; however, by 12 months, patients generally experienced reductions in fatigue beginning at 1 year, and these improvements were sustained at 2 years. Older age and a higher Expanded Disability Status Scale score were both linked with weaker improvements in fatigue measurements. Three studies also found that cognitive fatigue seemed to be decreased after HSCT.

The reviewers described the evidence surrounding HSCT’s effect on cognitive function as “inconclusive.” Patients appeared to experience a short-term deterioration in cognitive function after HSCT, only to bounce back months later, they wrote. In one study, after an initial decline in cognitive measurements, patients experienced improvement until there was only a statistically insignificant decline in cognitive function score after about 3 months following HSCT, and cognition improved significantly in certain areas at 1 year after transplant compared with baseline. In another extremely small study of 7 patients, 5 patients reportedly demonstrated significant declines in executive function at 2 months but function appeared to return to baseline by 24 months.

Two more studies indicated that mood was not affected by HSCT, according to the researchers. However, this evidence was limited, with one of the studies including only 7 patients, they noted.

Interpreting the Data

In an interview with Physician’s Weekly, David E. Freedman, MD, who was not involved in the study, says the study makes “an important contribution to the HSCT literature, identifying that there is limited evidence on this topic, evidence of bias in available investigations, and that most studies involved a small number of participants.”

However, he adds, “This review revealed promising evidence of a possible benefit of HSCT for quality of life and subjective fatigue, and possible adverse short-term effects of HSCT on cognition.”

Freedman is a researcher specializing in the psychologic and neurologic effects of MS. He emphasized that HSCT is a physically and psychologically rigorous therapy.

He notes that because HSCT is an invasive treatment with physical and psychologic risks, the results of the review should be interpreted with caution and that treatment decisions should be made in the context of a patient’s overall health.

“HSCT can be a very strenuous treatment process,” he tells Physician’s Weekly. “Although there is promising evidence of possible benefits for quality of life and fatigue, the available weak evidence must be balanced against the potential for risks and complications with HSCT, including adverse effects on cognition. The authors of this review appropriately note the importance of regular evaluation of neuropsychological outcomes before and after treatment. Notably, depression, anxiety, and cognitive dysfunction are common among people with MS. This review highlights how little is known about the impact of HSCT on these outcomes and the need for further study.”