Background and objective: Sexual dysfunction severely affects the quality of life of patients, but longitudinal studies of sexual function in multiple sclerosis are lacking. We performed a study on a group of patients with multiple sclerosis to evaluate the change in sexual function and to examine the relationship between sexual dysfunction and other clinical variables over time.
Methods: A 2-year follow-up study on 99 patients with definite multiple sclerosis. Information on sexual and sphincteric disturbances have been collected through face-to-face structured interviews. Disability, independence, cognitive performances and psychological functioning have also been assessed. Spearman rank correlation analysis corrected for multiple comparisons, and linear regression analysis have been performed to test variables relationship and remove the effect of potential confounding covariates.
Results: The proportion of patients with sexual dysfunction remained over 70% and did not change during the 2-year follow-up, but the extent and number of symptoms increased significantly The number of symptoms of sexual dysfunction did not change significantly after an exacerbation. Significantly, more patients than before the study resorted to counseling and discussed with doctors of sexual matters. In the univariate analysis, changes in sexual function over time correlated with changes in bladder function (r=0.47, p<0.0001) and EDSS score (r=0.41, p<0.0001), but the multivariate analysis demonstrated that only bladder dysfunction was independently related to sexual dysfunction (R=0.36, p=0.003) when the effect of psychological factors were removed.
Conclusions: Symptoms of sexual dysfunction increase in significance and number over time in patients with multiple sclerosis. Relapses did not influence the number of symptoms of sexual dysfunction, but a worsening of pre-existing symptoms cannot be excluded. The change of sexual function appears to be independently associated to bladder dysfunction.