Systemic lupus erythematosus (SLE) and its immunosuppressive treatment have a great impact on the patient__s life. Previous studies on SLE have focused on the optimisation of diagnosis and... Show moreSystemic lupus erythematosus (SLE) and its immunosuppressive treatment have a great impact on the patient__s life. Previous studies on SLE have focused on the optimisation of diagnosis and treatment. Less attention has been given to the impact of diagnosis and treatment on patients__ well-being. According to Engel__s biopsychosocial model there is a reciprocal and multifactorial relationship between disease characteristics and patients__ well-being and therefore the patient and not the disease should be the centre of focus. This thesis aimed to produce a biopsychosocial perspective on SLE by investigating both medical care and psychological functioning in patients with SLE. The main results show that a selective use of diagnostic procedures and monitoring of serum drug concentrations do not hamper disease outcome and may even reduce treatment burden. However, also low dose immunosuppressive treatment for SLE remains burdensome. This burden is reflected by a lowered HRQoL and lowered sexual functioning. In view of limitations in the extent to which immunosuppressive treatment can be further lowered, patients' illness perceptions may be targeted to enhance psychological functioning. In addition, treatment outcome may benefit from illness perception modification through a beneficial effect of positive (i.e. more adaptive) treatment perceptions on level of treatment adherence. Show less