Every-other-day interferon beta-1b versus once-weekly interferon beta-1a for multiple sclerosis (INCOMIN Trial) II: analysis of MRI responses to treatment and correlation with Nab

BACKGROUND

In RRMS, clinical exacerbations are usually associated with different types of active lesions at MRI, including: hyperintense lesions on T1-weighted post-gadolinium sequences; new hyperintense lesions or enlarging old lesions on PD/T2-weighted scans; or new hypointense lesions on T1-weighted pre-Gd sequences.

OBJECTIVE/METHODS

Primary outcome was the occurrence of patients with at least one active MRI lesion of the different types indicated above during treatment with 250 microg every other day (EOD) interferon beta (IFNbeta)-1b or 30 microg once weekly (OW) IFNbeta-1a in outpatients with RRMS (INCOMIN Trial).

RESULTS

The number of patients with at least one 'active' lesion, evaluated over the two-year follow-up, was significantly (P = 0.014) lower in the EOD IFNbeta-1 b arm (1 3/76, 17%) then in the OW IFNbeta-1a arm (25/73, 34%). NAb frequency over two-year follow-up was 22/65 (33.8%) in the EOD IFNbeta-1b arm and 4/62 (6.5%) in the OW IFNbeta-1a arm, significantly greater in the EOD IFNbeta-1b arm.

CONCLUSIONS

The development of MRI active lesions is strongly reduced by EOD-IFNbeta-1b compared with OW-IFNbeta-1a, indicating that EOD-IFNbeta-1b is more effective than OW-IFNbeta-1a in reducing ongoing inflammation and demyelination in MS. Logistic regression showed that NAb status did not affect the risk of MRI activity.

Terminal latency index in polyneuropathy with IgM paraproteinemia and anti-MAG antibody

Criteria for the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) are met by the polyneuropathy associated with immunoglobulin M (IgM) paraproteinemia and anti-myelin-associated glycoprotein (MAG) antibody (MAG-CIDP). However, MAG-CIDP differs from other types of CIDP, mainly in its poorer response to treatment. The utility of terminal latency index (TLI) as an electrophysiological marker for MAG-CIDP has been debated. In this study we confirmed its diagnostic usefulness and evaluated TLI threshold values for motor nerves investigated in routine nerve conduction studies. Median, ulnar, peroneal, and tibial TLIs of 11 subjects with MAG-CIDP, 18 with CIDP, and 76 healthy controls were compared, and threshold values for MAG-CIDP evaluated as the lowest value with a likelihood ratio higher than 10. Mean TLI values and TLIs of all but the peroneal nerve were significantly lower in MAG-CIDP. Median nerve TLI of 0.26 and ulnar nerve TLI of 0.33 were identified as the threshold TLI values for MAG-CIDP.

Interferon-beta dose and efficacy: the OPTIMS study

Interferon beta (IFN-beta) reduces exacerbation rates in patients with relapsing-remitting multiple sclerosis (MS), but some patients do not respond to treatment. Recent studies have shown a clear dose-response effect on the reduction of exacerbation rates, and on burden of disease accumulation and active lesion frequency seen on MRI. During treatment with 8 MIU IFN-beta we noticed a 30% rate of treatment failure. We then treated non-responders with 12 MIU IFN-beta and observed significant improvement in the clinical signs of disease activity. In order to compare the efficacy of two different doses of IFN-beta-1b, a multicenter study for the optimization of interferon for MS (OPTIMS) has been organized. The design of the study is presented here.

Anti-GM1 and anti-sulfatide antibodies in polyneuropathies. Threshold titers and accuracy

OBJECTIVES

To determine threshold titers and diagnostic accuracy of anti-GM1 and anti-sulfatide antibodies (Ab) for autoimmune polyneuropathies (PN) in overall and for particular subtypes of them.

MATERIALS AND METHODS

In this study 84 PN patients, 120 epileptics and 93 healthy controls' sera were tested by enzyme-linked immunosorbent assay for autoAbs and results confirmed by thin-layer chromatography. Frequencies of positive patients at increasing cut-off were compared to determine threshold titers. Accuracy was determined by Receiver Operator Characteristic analysis.

RESULTS

A 1:2,000 titer for IgM anti-GM1 and a 1:4,000 titer for IgM anti-sulfatide Ab resulted to be threshold titers for autoimmune PN in overall. IgM anti-GM1 and anti-sulfatide Ab had low discriminating capacity between autoimmune PN and other PN, but good discriminating capacity between motor neuropathy (for anti-GM1 Ab) or PN in IgM-paraproteinemia or chronic painful sensory axonal PN (for anti-sulfatide Ab) and other PN.

CONCLUSION

Our results suggest that testing IgM anti-GM1 or anti-sulfatide Ab is useful only for diagnostic confirmation of specific subtypes of autoimmune PN.

Autonomic nervous function in de novo parkinsonian patients in basal condition and after acute levodopa administration

The aims of this study were to assess autonomic nervous function in subjects with recently diagnosed Parkinson's disease (de novo patients) and to evaluate its changes following acute levodopa administration. In 13 patients (8 males, 5 females) and 13 age-matched control subjects, three cardiovascular autonomic function tests (Deep Breathing, Valsalva, Lying to Standing) were performed, the QT interval was calculated on a 12-lead electrocardiogram, and the response of plasma norepinephrine to standing was assessed in basal conditions. The cardiovascular tests and the measurement of the QT interval were repeated in de novo Parkinsonian patients 90 minutes after the administration of levodopa 200 mg per os. The results of the Deep Breathing and Valsalva tests were worse and the QT interval longer in patients than in control subjects (although the differences were not statistically significant). The heart rate increase at 30 seconds after standing up was significantly higher in Parkinsonian patients than in the control group. The response of plasma norepinephrine to standing was similar in both groups. Levodopa administration produced a slight improvement in the Deep Breathing test, a shortening of the QT interval and increased tachycardia on standing. Our data suggest that a mild subclinical impairment of parasympathetic function can be a feature of de novo Parkinsonian patients and that levodopa therapy could have a beneficial effect on this autonomic dysfunction.