Neutralizing antibodies (NABs) occur frequently in patients receiving interferon (IFN)-beta for multiple sclerosis (MS), but it is unclear whether occurrence of NABs is predictive for the persistence of NABs during continued IFN-beta therapy.
The authors used an antiviral neutralization bioassay to measure NABs blindly from 6 months up to 78 months in patients with MS who were followed for at least 24 months during treatment with IFN-beta. Patients were classified into three groups: 1) persistently NAB-negative patients, defined as patients without any positive samples at any time; 2) definitely NAB-positive patients, defined as patients who had at least two consecutive positive samples; and 3) patients with fluctuating NAB-positive and NAB-negative samples.
A total of 455 patients were included in the study. Overall, 52.3% of the patients were persistently NAB-negative, 40.9% became definitely NAB-positive, and the remaining 6.8% were fluctuating. More patients treated with IFN-beta-1a (Avonex) remained NAB-negative (p
Neutralising antibodies (NAbs) against interferon (IFN)-beta reduce the treatment effect in multiple sclerosis (MS). However, data from pivotal trials of IFN-beta in MS suggest that NAb-positive patients may have a reduced relapse rate during the first six to 12 months of therapy. We collected clinical data and plasma samples for NAb measurements prospectively, every six months, in 468 patients treated with the same IFN-beta preparation for at least 24 months. NAbs were measured blindly with a cytopathic effect (CPE) assay. During treatment months 0-6, patients who became NAb-positive had significantly fewer relapses compared to patients who maintained the NAb-negative status, whereas the opposite was observed after month 6. This is in accordance with observations in randomised studies of the three different IFN-beta preparations, showing that patients who become NAb-positive have lower relapse rates during the first six or 12 months of therapy. We hypothesise that low affinity NAbs, present early after the start of IFN-beta therapy, though neutralising in vitro in sensitive assays increase the half-life of IFN-beta in vivo and, thereby, enhance the therapeutic effect. With affinity maturation, NAbs effectively prevent IFN-beta binding to its receptors also in vivo and, hence, abolish the treatment effect.
The Danish Multiple Sclerosis Registry was established in 1948 in continuation with a nationwide survey of the prevalence of Multiple Sclerosis (MS) in Denmark. The register has since collected information on MS patients from all Danish departments of neurology, practising neurologists, MS rehabilitation centres, the National Patient Registry, the Danish MS Society, and departments of neuropathology. The registry is linked with the Danish Central Population Registry. The completeness has been estimated at more than 90%. All cases are reclassified by two neurologists as to diagnosis and year of onset. 12 070 cases with a confirmed diagnosis of MS are kept in the databases. They were prevalent in 1949 or have had onset in the period 1948 - 1993. The registry is continuously updated with new information on registered cases and new cases. The crude average annual incidence rate 1980 - 89 was 4.99/105; the prevalence rate was 112/105 by 1 January 1990. Cross-linking with other registers have enabled analytical prospective epidemiological studies, and the registry has provided population based unbiased samples of patients for a number of clinical studies.
The Danish Multiple Sclerosis Registry was formally established in 1956 but started operating in 1949 with a nationwide prevalence survey. Since then, the Registry has continued collecting data on new and old cases of multiple sclerosis (MS) or suspected MS from multiple sources. The Registry reclassifies cases according to standardized diagnostic criteria (currently those of Poser et al). A total of 14,441 cases fulfilling the diagnostic criteria had been registered at the most recently completed follow-up by 1 January 1997; 10,851 had onset from 1948 to 1996 and 3560 before 1948. The completeness has formerly been estimated at about 90%, higher for cohorts with older onset and lower for cohorts with onset close to follow-up. The estimated validity of the diagnosis for autopsy cases classified as definite MS in the Registry is 94%. A long-term nationwide Registry has proved to be a valuable instrument for monitoring incidence and prevalence, analysing survival, performing genetic analysis, providing unselected patient samples for clinical analyses, performing case-control studies and prospective studies and estimating the need for treatment and care.
Initiation of fingolimod treatment is associated with a transient decrease of heart rate, and atrioventricular (AV) conduction block may occur.
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.
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.
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.
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.
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.
Previous studies of natalizumab (Tysabri) in relapsing multiple sclerosis (MS) patients have included patients with moderate disease activity. We studied a patient population with high disease activity.
We analyzed data from 234 consecutive, natalizumab-treated patients, followed for at least 3 months. Three groups of patients were eligible for natalizumab therapy: patients with two or more documented relapses or sustained increase of 2 EDSS points on disease modifying therapy (DMT) in the previous year; patients switching from mitoxantrone; and patients with very active MS as de novo therapy.
During a median observation time of 11.3 months (range 3.0-21.5) the annualized relapse rate decreased to 0.68 from a pre-treatment rate of 2.53 (73% reduction). We assessed the annualized relapse rate in three subgroups: (i) 0.83 in 14 (6.0%) de novo treated patients; (ii) 0.71 in 175 (74.8%) patients with >or=2 relapses or sustained increase in EDSS of >or=2 points on a first-line DMT; and (iii) 0.56 in 45 (19.2%) patients switching from mitoxantrone. Nine anaphylactoid reactions, two severe, were reported. Out of 215 patients 7 (3%) were persistently positive for antibodies to natalizumab.
Tysabri appears to be effective in MS patients with high disease activity, but the relapse rate was higher than in the pivotal study after the first treatment year. This is likely to reflect differences in disease activity before the initiation of natalizumab treatment.
The Danish Multiple Sclerosis Registry (DMSR) is a national register based upon the ethnically homogeneous Danish population of about 5 millions. The DMSR was founded in 1956 following a nationwide Danish prevalence survey of MS in 1949 and a continuous registration of incident cases of MS since January 1, 1948. Included in DMSR are all Danish cases of MS (or suspicion of MS) diagnosed by a neurologist or a department of neurology. The sources of notification are the 22 neurological departments in Denmark, the National Patient Registry, the neuropathological departments, the Registry of Causes of Death, and, up to 1975, the Disablement Insurance Court. Notified cases which do not comply with the standardized diagnostic criteria of the DMSR are excluded. An estimate of the completeness of the DMSR is 90-95% and the validity is around 94%. Age- and sex-specific incidence rates of MS for the interval 1948-64 are presented. The crude annual incidence rate of MS in Denmark was in the year 1948-64 4.42 per 100,000 population, 22% higher in females than males. There was a significant geographical variation of incidence rates and a significant downward trend in incidence rates during the interval, whereas the prevalence rates showed a slight increase.
The Danish National Patient Register, Landspatientregistret (LPR), is a register of all hospital discharges and outpatient treatments in Denmark.
It is increasingly used in research so it is important to understand to what extent this can be used as an accurate source of information. Virtually all patients in Denmark with multiple sclerosis (MS) are reported to the Combined MS Registry (DMSR), so this was used as the standard which the LPR was compared against.
All residents of Denmark are assigned a unique Civil Register (CPR) number; this was used to compare data between registers. The LPR completeness was estimated by the proportion of cases from the DMSR that could be retrieved from the LPR. The LPR validity was estimated by the proportion of cases, listed in the LPR and DMSR, in whom the MS diagnosis could be confirmed as definite/probable/possible by the DMSR.
We found that 86.9% of those who were DMSR listed with an approved MS diagnosis were also listed in the LPR with a MS diagnosis. The diagnosis was valid in 96.3% of patients listed in the LPR when compared against the DMSR.
The low completeness reduces the usefulness of the LPR in epidemiological MS research, in particular incidence studies. The study also found that the completeness of the LPR could be increased to 92.8% by including LPR records from other departments in addition, but this reduced the validity of the LPR to 95.1%. However, these results cannot uncritically be applied to registration of other diseases in the LPR.
The incidence rates of multiple sclerosis (MS) in Denmark were estimated as a result of a continuous nationwide epidemiological survey since 1948 by the Danish Multiple Sclerosis Registry (DMSR). Among cases notified to the DMSR, 6,478 met the diagnostic criteria and had onset of MS from 1948 through 1982. The crude annual incidence rate was 4.45/100,000 and the lifetime cumulative incidence rate was 0.32%. The female/male ratio was 1.37:1. Crude incidence rates declined during the period 1952-1967. After 1967 the incidence seemed to rise again but in an irregular pattern. The decline in incidence involved only cases up to the age of 35. The subsequent increase was most marked in females and in the age groups over 45 years.