Influence of Apolipoprotein E Plasma Levels and Tobacco Smoking on the Induction of Neutralising Antibodies to Interferon-Beta

Interferon-beta (IFN-beta) therapy for multiple sclerosis (MS) is associated with a potential for induction of neutralizing antibodies (NAbs). Because immune reactivity depends on changes in lipoprotein metabolism, we investigated whether plasma lipoprotein profiles could be associated with the development of NAbs. Thirty-one female MS patients treated with subcutaneously administered IFN-beta were included. Demographic and clinical characteristics were compared between NAbs response groups using t tests for continuous and logistic regression analysis and Fisher's exact tests for categorical data, respectively. Multivariate logistic regression was used to evaluate the effect of potential confounders. Patients who developed NAbs had lower apoE levels before treatment, 67 (47-74) mg/L median (interquartile range), and at the moment of NAb analysis, 53 (50-84) mg/L, in comparison to those who remained NAb-negative, 83 (68-107) mg/L, P = 0.03, and 76 (66-87) mg/L, P = 0.04, respectively. When adjusting for age and smoking for a one-standard deviation decrease in apoE levels, a 5.6-fold increase in the odds of becoming NAb-positive was detected: odds ratios (OR) 0.18 (95% CI 0.04-0.77), P = 0.04. When adjusting for apoE, smoking habit became associated with NAb induction: OR 5.6 (95% CI 1.3-87), P = 0.03. These results suggest that apoE-containing lipoprotein metabolism and, possibly, tobacco smoking may be associated with risk of NAb production in female MS patients treated with IFN-beta.

Slipped Capital Femoral Epiphysis. A Report of 4 Cases Occurring in One Family

We describe slipped capital femoral epiphysis in 4 members of a black, obese family, who were all first-degree relatives. The aetiology of slipped capital femoral epiphysis is unknown, although it is thought to be multifactorial. Genetic predisposition and environmental factors have been associated with the condition. A familial incidence with at least two cases in the same family has been reported. In epidemiological studies, this incidence ranges from 3% to 35%. Our cases were investigated in an attempt to find a possible aetiological genetic factor. A genetic predisposition with an autosomal dominant pattern of transmission is suggested, although environmental variables must be considered as provocative factors.