Early versus later treatment start in multiple sclerosis: a register-based cohort study

BACKGROUND AND PURPOSE

To assess long-term treatment effectiveness of disease-modifying therapy (DMT) initiated early in disease course versus later treatment start.

METHODS

We included all Danish patients with multiple sclerosis (MS) treated with DMT through two nationwide population-based MS registries. Patients were categorized as early treated if treatment started within 2 years after the first MS symptom (n = 2316) and later treated if treatment started between 2 and 8 years after clinical onset (n = 1479). We compared time from treatment start to progression to an Expanded Disability Status Scale (EDSS) score of 6 and mortality between cohorts as hazard ratio (HR) using a Cox proportional hazards model with adjustment for stabilized inverse probability of treatment weights. Several sensitivity analyses were conducted.

RESULTS

The median follow-up time of 3795 patients was 7.0 (range 0.6-19.5) years for the EDSS score of 6 outcome and 10.4 (range 1.2-20.1) years for the mortality outcome. Patients with later treatment start showed a 42% increased hazard rate of reaching an EDSS score of 6 compared with the early-treated patients [HR, 1.42; 95% confidence interval (CI), 1.18-1.70; P < 0.001]. When stratified by sex, the increased hazard among later-treated women persisted (HR, 1.53; 95% CI, 1.22-1.93; P < 0.001), whereas the HR was lower in men (1.25; 95% CI, 0.93-1.69; P = 0.15). Mortality was increased by 38% in later starters (HR, 1.38; 95% CI, 0.96-1.99; P = 0.08).

CONCLUSIONS

Patients who started treatment with DMT later reached an EDSS score of 6 more quickly compared with patients who started early and the delay showed a tendency to shorten time to death. Our results support the use of early treatment.

Registers of multiple sclerosis in Denmark

There are two nationwide population-based registers for multiple sclerosis (MS) in Denmark. The oldest register is The Danish Multiple Sclerosis Registry (DMSR), which is an epidemiological register for estimation of prevalence and incidence of MS and survival, and for identifying exposures earlier in life that may affect the risk of MS. This register has no systematic follow-up data except for survival. The DMSR has over the years published nationwide incidence- and prevalence data from Denmark and has been involved in a number of 'historical prospective' studies to elucidate the association between a number of different environmental exposures in the past and the subsequent risk of MS. Some of these studies have been able to exonerate suspected risk factors. The other register, the nationwide Danish Multiple Sclerosis Treatment Register, is a follow-up register for all patients who have received disease-modifying treatments since 1996. It has, in particular, contributed to the knowledge of the role of antibodies against the biological drugs used for the treatment of MS.

Anti-CD20 antibody therapy and risk of infection in patients with demyelinating diseases

BACKGROUND

Anti-CD20 antibody therapy may be associated with an increased risk of infections. We therefore investigated risk factors for infection in patients with demyelinating diseases treated with anti-CD20 antibody therapy.

METHODS

In this retrospective uncontrolled study, patients ever treated with anti-CD20 antibodies at an academic clinic were identified through the Danish Multiple Sclerosis Registry (DMSR). Data were collected from medical charts and the DMSR. We assessed occurrence of severe infections (requiring hospitalization), varicella zoster virus (VZV), major comorbidities and routine laboratory values for lymphocytes, IgG and IgM.

RESULTS

A total of 447 patients ever treated with anti-CD20 antibody therapy were identified; of these 416 with 649 patient years of follow-up were still under therapy. In this group, seven patients had VZV infections, and 16 patients had been hospitalized with infections during up to three years of follow-up on anti-CD20 therapy. Comorbidity was recorded in 80 patients. The risk of severe infection was associated with comorbidities, higher age, longer duration of treatment, and higher Expanded Disability Status Scale (EDSS) scores. In multivariable analyses treatment duration, EDSS scores and presence of comorbidity were independently associated with risk of severe infections. Serum concentrations of IgG and IgM decreased with increasing duration of therapy but were not associated with risk of severe infections. Patients with VZV infection had lower lymphocyte counts and lower serum concentrations of IgM. In multivariable analyses only lymphocyte counts were independently associated with risk of VZV infection.

CONCLUSIONS

In this retrospective study of patients treated with anti-CD20 antibodies, the risk of infections requiring hospitalization was independently associated with comorbidities, duration of treatment, and higher EDSS scores. Risk of VZV infection was independently associated with lymphopenia. Future studies investigating strategies for mitigating risk of infection in patients treated with anti-CD20 antibodies are warranted, especially for older patients, patients with higher levels of disability and for patients with a longer duration of treatment.

Shift work at young age is associated with increased risk of multiple sclerosis in a Danish population

BACKGROUND

Epidemiological studies suggest an important role for environmental factors in developing multiple sclerosis (MS). Furthermore several studies have indicated that the effect of environmental factors may be especially pronounced in adolescents. Recently only one study investigated and found that shift work at young age is associated with an increased risk of developing MS. In this study we focused on the effect of shift work in the vulnerable period between 15-19 years.

OBJECTIVE

The aim of this study was to investigate the association between shift work at young age and the risk of developing MS.

METHODS

We performed a large case-control study including 1723 patients diagnosed with MS and 4067 controls. MS patients were recruited from the Danish Multiple Sclerosis Biobank and controls from The Danish Blood Donor Study. Information on working patterns and lifestyle factors was obtained using a comprehensive lifestyle-environmental factor questionnaire with participants enrolled between 2009 and 2014. Logistic regression models were used to investigate the association between shift work at age 15-19 years and the subsequent risk of MS and were controlled for effects due to established MS risk factors.

RESULTS

We found a statistically significant association when total numbers of night shifts were compared with non-shift workers. For every additional 100 night shifts the odds ratio (OR) for MS was 1.20 (95% confidence interval (CI), 1.08-1.34, p=0.001). Increasing intensity of shift work also increased MS risk. For every additional night per month the OR was 1.04 (95% CI, 1.01-1.06, p=0.002). Duration of shift work in years was not associated with risk of MS.

CONCLUSION

This study supports a statistically significant association between shift work at age 15-19 years and MS risk.

Role of socio-economic and reproductive factors in the risk of multiple sclerosis

The incidence of multiple sclerosis is increasing in Danish women. Their risk of developing multiple sclerosis has more than doubled in 25 years while it has remained virtually unchanged for men. The explanation for these epidemiological changes should be sought in the environment as they are too rapid to be explained by gene alterations. We investigated the effect of numerous biological social physical and chemical environmental exposures in different periods of life. These data were available from population-based registries and were used in a case-control approach. This study database included all multiple sclerosis cases (n = 1403) from the Danish MS Registry with clinical onset between 2000 and 2004 as well as 35,045 controls drawn by random from the Danish Civil Registration System and matched by sex year of birth and residential municipality at the reference year. Having newborn children reduced the risk of multiple sclerosis (MS) in women but not in men. Childbirths reduced the risk of MS by about 46% during the following 5 years. Even pregnancies terminated early had a protective effect on the risk of developing MS suggesting a temporary immunosuppression during pregnancy. Our data on social behaviour regarding educational level income and relationship stability did not indicate reverse causality. A greater likelihood to be exposed to common infections did not show any effect on the risk of MS neither in puberty nor in adulthood. Socio-economic status and lifestyle expressed in educational level and sanitary conditions in youth were not associated with the risk of MS.

Gender effects on treatment response to interferon-beta in multiple sclerosis

BACKGROUND

Gender appears to play a role in incidence and disease course of multiple sclerosis (MS).

OBJECTIVE

The objective was to determine whether male and female patients with MS respond differently to interferon-beta treatment in terms of reduction in relapse rates.

METHODS

We included all 2033 patients with relapsing-remitting MS who started treatment with interferon-beta from 1996 to 2003, identified from the Danish Multiple Sclerosis Treatment Register. We defined neutralizing antibody (NAb)-positive and NAb-negative periods in the single patient by the results of the NAb tests. Patients served as their own controls, and relapse rates were compared between NAb-negative and NAb-positive periods.

RESULTS

NAbs significantly abrogated the interferon-beta treatment efficacy in both genders. The all-over women:men relapse rate ratio irrespective of NAb status was 1.47 (95%CI; 1.28-1.68). In a generalized linear Poisson models analysis with relapse counts as response variable, the main effects NAbs, sex, age at treatment start and number of relapses in 2 years before treatment start were strongly significant, but the effect of NAbs on relapse rates did not differ significantly between men and women.

CONCLUSION

As NAbs influenced the on-treatment relapse rates strongly in both sexes but without statistical significant difference, there is no indication of different effects of interferon-beta in men or women.

Mitochondrial mutation as a probable causative factor in familial progressive tubulointerstitial nephritis

Renal biopsy of two children and a maternal relative, diagnosed with severe progressive tubulointerstitial nephritis, has shown the presence of distorted mitochondria. Mitochondrial DNA from the blood of these patients was analysed. No major deletions were found, but an A to G mutation was detected in position 5656. It is proposed that this mutation might play a causative role in the renal disease of the patients.

Early safety and efficacy of fingolimod treatment in Denmark

BACKGROUND

Initiation of fingolimod treatment is associated with a transient decrease of heart rate, and atrioventricular (AV) conduction block may occur.

OBJECTIVE

To evaluate the therapeutic effect and safety of fingolimod treatment in MS patients in Denmark with focus on cardiac and pulmonary side effects at treatment onset.

MATERIALS & METHODS

We analysed data from the first 496 fingolimod-treated Danish patients, observed for at least 3 months. In a subset of 204 patients, we monitored cardiac and pulmonary adverse effects following treatment initiation.

RESULTS

The overall annualized relapse rate (ARR) was 0.37 (95% CI 0.31-0.44); 0.22 (95% CI 0.03-0.81) in de novo-treated patients, 0.29 (95% CI; 0.23-0.37) in patients switching from IFN-beta or GA and 0.46 (9 5% CI 0.34-0.60) after natalizumab. In the subset of 204 patients, 8 (3.9%) required prolonged cardiac monitoring due to bradycardia and/or second-degree AV block type I. All patients recovered spontaneously. Two patients discontinued fingolimod. Eleven (5.4%) patients reported respiratory complaints and two of these patients discontinued treatment.

CONCLUSIONS

Fingolimod appears to be safe and effective in MS patients in a clinical setting. Mild cardiac adverse effects occurred at a similar rate as in clinical trials.

Educational achievements of children of parents with multiple sclerosis: A nationwide register-based cohort study

Little is known about the impact of parental multiple sclerosis (MS) on offspring's educational attainment. The objective of the study was to examine educational achievements in offspring of parents with MS compared with matched children of parents without MS in a nationwide register-based cohort study. Children of all Danish-born residents with onset between 1950 and 1986 were identified by linking the Danish Multiple Sclerosis Registry with the Civil Registration System. Twins, children with MS, and emigrated persons were excluded. The reference cohort consisted of randomly drawn individuals from the Civil Registration System without parental MS matched 8:1 to the MS offspring by sex and year of birth. Information about education was linked to the cohorts from nationwide educational registries. We included 4177 children of MS parents and 33,416 reference persons. Children of MS parents achieved statistically significant higher average grades than the reference cohort in their final exam of basic school with a mean grade difference of 0.46 (95 % CI 0.22-0.69; p = 0.0002). We found no difference in achievement of educational level above basic school (OR 1.04; 95 % CI 0.98-1.10; p = 0.20). There was a trend toward more MS offspring attaining health-related educations (OR 1.10; 95 % CI 1.00-1.21; p = 0.06). In conclusion, children of MS parents showed a small advantage in grade point average in final examinations in basic school, and they more often tended toward health-related educations. This study revealed no negative consequences of parental MS on grades and highest educational level achieved.

Impact of methodological choices in comparative effectiveness studies: application in natalizumab versus fingolimod comparison among patients with multiple sclerosis

Background

Natalizumab and fingolimod are used as high-efficacy treatments in relapsing–remitting multiple sclerosis. Several observational studies comparing these two drugs have shown variable results, using different methods to control treatment indication bias and manage censoring. The objective of this empirical study was to elucidate the impact of methods of causal inference on the results of comparative effectiveness studies.

Methods

Data from three observational multiple sclerosis registries (MSBase, the Danish MS Registry and French OFSEP registry) were combined. Four clinical outcomes were studied. Propensity scores were used to match or weigh the compared groups, allowing for estimating average treatment effect for treated or average treatment effect for the entire population. Analyses were conducted both in intention-to-treat and per-protocol frameworks. The impact of the positivity assumption was also assessed.

Results

Overall, 5,148 relapsing–remitting multiple sclerosis patients were included. In this well-powered sample, the 95% confidence intervals of the estimates overlapped widely. Propensity scores weighting and propensity scores matching procedures led to consistent results. Some differences were observed between average treatment effect for the entire population and average treatment effect for treated estimates. Intention-to-treat analyses were more conservative than per-protocol analyses. The most pronounced irregularities in outcomes and propensity scores were introduced by violation of the positivity assumption.

Conclusions

This applied study elucidates the influence of methodological decisions on the results of comparative effectiveness studies of treatments for multiple sclerosis. According to our results, there are no material differences between conclusions obtained with propensity scores matching or propensity scores weighting given that a study is sufficiently powered, models are correctly specified and positivity assumption is fulfilled.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01623-8.

Disability in progressive MS is associated with T2 lesion changes

BACKGROUND

Progressive multiple sclerosis (MS) is characterised by diffuse changes on brain magnetic resonance imaging (MRI), which complicates the use of MRI as a diagnostic and prognostic marker. The relationship between MRI measures (conventional and non-conventional) and clinical disability in progressive MS therefore warrants further investigation.

OBJECTIVE

To investigate the relationship between clinical disability and MRI measures in patients with progressive MS.

METHODS

Data from 93 primary and secondary progressive MS patients who had participated in 3 phase 2 clinical trials were included in this cross-sectional study. From 3T MRI baseline scans we calculated total T2 lesion volume and analysed magnetisation transfer ratio (MTR) and the diffusion tensor imaging indices fractional anisotropy (FA) and mean diffusivity (MD) in T2 lesions, normal-appearing white matter (NAWM) and cortical grey matter. Disability was assessed by the Expanded Disability Status Scale (EDSS) and the MS functional composite.

RESULTS

T2 lesion volume was associated with impairment by all clinical measures. MD and MTR in T2 lesions were significantly related to disability, and lower FA values correlated with worse hand function in NAWM. In multivariable analyses, increasing clinical disability was independently correlated with increasing T2 lesion volumes and MTR in T2 lesions.

CONCLUSION

In progressive MS, clinical disability is related to lesion volume and microstructure.

Plasma factors influencing prostacyclin-like activity in patients with diabetic microangiopathy

Plasma factors influencing PGI2-like activity in 19 patients with diabetes mellitus /Dm/ and 17 controls were studied through a comparison with the signs of retinal and glomerular angiopathy. The plasma PGI2 supporting activity /PSA/ was lower in 15 Dm cases than in the controls. Inhibitory activity against PGI2 production was detected in 6 patients. In the cases of more serious retinopathy associated with glomerulopathy, a significantly lower level of PSA was observed than in patients with mild retinopathy without glomerular diseases. The plasma concentrations of total and LDL-cholesterol were significantly higher, while the level of HDL-cholesterol was lower than in the controls. There was a positive correlation between PSA and HDL-cholesterol values and a negative correlation between PSA and LDL-cholesterol levels, which relates to an inhibitory effect of LDL and a protective role of HDL in PGI2 synthesis.

Factors associated with treatment escalation among MS specialists and general neurologists: Results from an International cojoint study

BACKGROUND

Previous studies in multiple sclerosis (MS) showed that therapeutic inertia (TI) affects 60-90% of neurologists and up to 25% of daily treatment decisions. The objective of this study was to determine the most common factors and attribute levels associated with decisions to treatment escalation in an international study in MS care.

METHODS

300 neurologists with MS expertise from 20 countries were invited to participate. Participants were presented with 12 pairs of simulated MS patient profiles described by 13 clinically relevant factors. We used disaggregated discrete choice experiments to estimate the weight of factors and attributes affecting physicians' decisions when considering treatment selection. Participants were asked to select the ideal candidate for treatment escalation from modest to higher-efficacy therapies.

RESULTS

Overall, 229 neurologists completed the study (completion rate: 76.3%). The top 3 weighted factors associated with treatment escalation were: previous relapses (20%), baseline expanded disability status scale [EDSS] (18%), and MRI activity (13%). Patient demographics and desire for pregnancy had a modest influence (≤ 3%). We observed differences in the weight of factors associated with treatment escalation between MS specialists and non-MS specialists.

CONCLUSIONS

Our results provide critical information on factors influencing neurologists' treatment decisions and should be applied to continuing medical education strategies.

NfL and GFAP in serum are associated with microstructural brain damage in progressive multiple sclerosis

BACKGROUND

The potential of neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) as biomarkers of disease activity and severity in progressive forms of multiple sclerosis (MS) is unclear.

OBJECTIVE

To investigate the relationship between serum concentrations of NfL, GFAP, and magnetic resonance imaging (MRI) in progressive MS.

METHODS

Serum concentrations of NfL and GFAP were measured in 32 healthy controls and 32 patients with progressive MS from whom clinical and MRI data including diffusion tensor imaging (DTI) were obtained during three years of follow-up.

RESULTS

Serum concentrations of NfL and GFAP at follow-up were higher in progressive MS patients than in healthy controls and serum NfL correlated with the EDSS score. Decreasing fractional anisotropy (FA) in normal-appearing white matter (NAWM) correlated with worsening EDSS scores and higher serum NfL. Higher serum NfL and increasing T2 lesion volume correlated with worsening paced autitory serial addition test scores. In multivariable regression analyses with serum GFAP and NfL as independent factors and DTI measures of NAWM as dependent factors, we showed that high serum NfL at follow-up was independently associated with decreasing FA and increasing MD in NAWM. Moreover, we found that high serum GFAP was independently associated with decreasing MD in NAWM and with decreasing MD and increasing FA in cortical gray matter.

CONCLUSION

Serum concentrations of NfL and GFAP are increased in progressive MS and are associated with distinct microstructural changes in NAWM and CGM.

[Iodine deficiency in cardiovascular diseases]

The thyroid hormone deficiency on cardiovascular function can be characterized with decreased myocardial contractility and increased peripheral vascular resistance as well as with the changes in lipid metabolism. 42 patients with cardiovascular disease (mean age 65 +/- 13 yr, 16 males) were investigated if iodine insufficiency can play a role as a risk factor for the cardiovascular diseases. The patients were divided in 5 subgroups on the ground of the presence of hypertension, congestive heart failure, cardiomyopathy, coronary disfunction and arrhythmia. Urine iodine concentration (5.29 +/- 4.52 micrograms/dl) was detected with Sandell-Kolthoff colorimetric reaction. The most decreased urine iodine concentration was detected in the subgroups with arrhythmia and congestive heart failure (4.7 +/- 4.94 micrograms/dl and 4.9 +/- 4.81 micrograms/dl, respectively). An elevated TSH level was found by 3 patients (5.3 +/- 1.4 mlU/l). An elevation in lipid metabolism (cholesterol, triglyceride) associated with all subgroups without arrhythmia. In conclusion, the occurrence of iodine deficiency in cardiovascular disease is frequent. Iodine supplementation might prevent the worsing effect of iodine deficiency on cardiovascular disease.