In this blog, our overarching goal has been to keep our readers up to date with the latest research in MS. One of the things I’ve noted in this time is that the vast wealth information out there isn’t insurmountable – you only need to select the ones that appeal to you, or are relevant to your practice. Information/’knowledge’ is probably the last bastion of monetizable commodity in the 21st century. However, with knowledge comes responsibility. So, if you’re reading the latest recommendation on our site or any other site for that matter, ask yourself: is this relevant to me?
There are many drugs and treatments out there (many of which you may have picked up from this blog), but being on all of them together may not be good for you. In a study from Rostock (Germany), they concluded that there is a great potential for drug-drug interactions (DDIs) from polypharmacy (i.e. being on at least 5 drugs at any one time).
“DDIs account for 20% of adverse events, which cause between US$30 and $180 billion annually and are responsible for about 770,000 deaths“.
They found in women of childbearing age with MS, 41% had polypharmacy; the most frequent drug combinations were dietary supplements and osteoporosis drugs (Figure 1). They also found not surprisingly, polypharmacy was related to older age (average age 43 years versus 36 years), disability (average EDSS scores: 6.5 versus 2.0), a progressive disease course and other medical conditions.
In their cohort, a mean of 4.2 drugs per patient (range: 0–15 drugs) resulted in 1033 potential DDIs (Figure 2). It is estimated that the likelihood of detecting at least one DDI in someone correlates with the number of drugs taken: ‘50% for people taking 5–9 drugs, 81% with 10–14 drugs, 92% with 15–19 drugs and 100% with at least 20 drugs’. It is also quite astonishing that the authors report that 80% of their potential drug interactions lacked evidence, so clearly more analysis is needed.
If you’re interested in looking at the potential drug interactions of your medications one useful site is the British National Formulary (BNF): https://bnf.nice.org.uk/interaction/.
Ther Adv Neurol Disord. 2020 Dec 19;13:1756286420969501. doi: 10.1177/1756286420969501. eCollection 2020.
The risk of polypharmacy, comorbidities and drug-drug interactions in women of childbearing age with multiple sclerosis
Background and aims: Multiple sclerosis (MS) is the most common neuroimmunological disease of the central nervous system in young adults. Despite recommended contraception, unplanned pregnancies can occur in women of childbearing age with MS. MS- and comorbidities-related multimedication in these patients represents a potential risk. We aimed to raise awareness regarding the frequency of polypharmacy and drug-drug interactions (DDIs) in female MS patients of childbearing age.
Methods: Sociodemographic, clinical and pharmaceutical data were collected through patient records, clinical investigations and structured patient interviews of 131 women with MS. The clinical decision support software MediQ was used to identify potential DDIs. A medication and DDI profile of the study population was created by statistical analysis of the recorded data.
Results: Of the 131 female MS patients, 41.2% were affected by polypharmacy (concurrent use of ⩾5 drugs). Polypharmacy was associated with higher age, higher degree of disability, chronic progressive MS disease course and comorbidities. With an average intake of 4.2 drugs per patient, a total of 1033 potential DDIs were identified. Clinically relevant DDIs were significantly more frequent in patients with polypharmacy than in patients without polypharmacy (31.5% versus 5.2%; Fisher’s exact test: p < 0.001).
Conclusion: For the first time, a comprehensive range of potential DDIs in women of childbearing age with MS is presented. Polypharmacy is associated with the occurrence of clinically relevant DDIs. This shows the need for effective and regular screening for such interactions in order to prevent avoidable adverse effects.