Risk Tolerance for Therapies Linked to Age, Sex and Disability

Sex, age, disability level, and current disease-modifying therapy use are linked to how multiple sclerosis (MS) patients weigh the potential benefits and safety risks of treatments, new research from two teams funded by the National Multiple Sclerosis Society shows.

These studies shed light on how MS patients’ tolerance for risk influences their treatment decisions, which can help improve treatment satisfaction and adherence.

The most recent research article, “A survey of risk tolerance to multiple sclerosis therapies,” was published this month in the journal Neurology. This study followed the publication “Probability discounting of treatment decisions in multiple sclerosis: associations with disease knowledge, neuropsychiatric status, and adherence,” in the journal Psychopharmacology in November 2018.

Guiding MS patients to the best treatment requires not only an assessment of benefits and risks, but also an awareness of their — and caregiver and loved ones — preferences regarding risks considered acceptable.

According to a news release, the National MS Society (NMSS) released in 2015 a request for proposals to develop a tool enabling personalized medicine and optimal treatment decision-making. Two Health Care Delivery and Policy Contracts were awarded to Robert J. Fox, MD, with the Cleveland Clinic, and Jared Bruce, PhD, with the University of Missouri.

The Neurology study was conducted by Fox and colleagues. Researchers set focus groups involving MS patients and their caregivers at four geographically distant clinics across the U.S. to gain insight into factors related to their preferences while choosing a disease-modifying therapy (DMT).

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Based on themes emerging from these focus group discussions, researchers created a survey that was then completed by 3,171 MS patients recruited through the National MS Society and the North American Research Committee on MS (NARCOMS) registry.

The survey assessed the level of tolerance that participants had for real-world risks linked with currently available therapies. Participants scored risk levels from mild to severe, with six different hypothetical complications: infection, skin rash, liver injury, kidney injury, thyroid injury, and progressive multifocal leukoencephalopathy (PML) — a viral brain infection that can be lethal or cause severe disability.

Responses showed a highest risk tolerance for thyroid injury and infection, and the least risk tolerance for PML and kidney injury. It is important to note that a large proportion of the group studied was “risk averse” — meaning that, depending on the complication, almost 4 in 10 participants were unwilling to assume any risk for the therapy’s benefit.

Fox’s team found that men were more risk tolerant than women, (and women were 79 percent of those returning the survey). Respondents with greater disability, as well as those taking oral and infusion therapies, also reported a greater risk tolerance in comparison to those using injectables. (Disability was measured using Patient Determined Disease Steps, or PDDS, which evaluates walking ability on a rising disability scale of 0 to 6.)

Increasing age (51 and older) was linked to a lower risk tolerance than in those age 40 or younger, and was especially strong for kidney or liver injury and PML.

No significant difference was found across age groups for infection, skin rash, and thyroid injury.

“Our findings indicate that RT [risk tolerance] differs according to sex, age, disability level, and current DMTs [disease-modifying therapies],” the team wrote.

“Understanding risk perception and RT, as well as its heterogeneity, can ultimately lead to greater satisfaction with treatment choices and perhaps treatment adherence,” researchers added.

The second publication, from Bruce’s team, assessed MS patients in the context of several factors, including “probability discounting” — how quickly someone lowers the value of a reward as it becomes increasingly less likely to occur.

In the study, 208 patients were recruited through the University of Kansas Medical Center MS Clinic and the local office of the National MS Society. They underwent cognitive testing, and completed questionnaires measuring clinical, social, and neuropsychiatric functioning, as well as “probability discounting.”

Results were mixed. Patients who dismissed the potential benefits of therapy quicker citing side effects usually had less knowledge of MS, and showed a poorer adherence to treatment. Of note, those who discounted treatments with higher efficacy were more likely to have cognitive issues.

“High rates of discounting based on risks were associated with poor treatment adherence and less disease-specific knowledge. In contrast, high rates of discounting of benefits was associated with poorer cognitive functioning,” the researchers wrote.

According to Bruce’s team, these results “represent an important early step in understanding individual differences associated with medical decision making in MS.”

Overall, the teams showed that male sex, younger age, and greater disability are associated with a greater risk tolerance, and a lower risk tolerance is associated with poor treatment adherence.

Both studies offer insights into how MS patients perceive treatment decisions, and suggest that a better understanding of choices can help to improve treatment adherence and satisfaction.