Health-related Quality of Life decreases with disease severity in German HSP Patients

Background: The Hereditary Spastic Paraplegias (HSP) comprise of a clinically and genetically heterogeneous group of neurodegenerative disorders characterised by a slowly progressive spastic gait disorder. Clinically, „pure“ and „complicated“ forms are distinguished. The impact of HSP on quality of life is not known so far. Therefore, we assessed the health-related quality of life with the Short-Form 36 (SF-36) quality of life questionnaire in a sample of HSP patients of the GeNeMove network project.

Patients and Methods: 123 patients with HSP (47.2% women, mean age 47.4; 16–80 years) participating in the GeNeMove project were included. Inheritance was predominantly autosomal-dominant (61.0%), 34.1% had mutations in the most common SPG4 („Spastin“) gene. Patients were examined using the standardized Spastic Paraplegia Rating Scale (SPRS, range 0–52 points, Schüle et al., 2006). The SF-36 questionnaires were filled in during regular visits. The SF-36 consists of 36 questions concerning different aspects of health related quality of life (QoL). Answers are computed in 8 scales representing distinct fields of QoL. These subscales are again computed in 2 summary scores, the mental and physical component scores (MCS and PCS). These scores simplify the interpretation of results and have been shown to be a reliable instrument. MCS and PCS normal values are 50 (SD 10) with higher scores indicating positive results.

Results: 68.3% of the patients had a clinically „pure“ form of HSP. Age of onset was 30.6 years (SD 15.9, 0–66). The mean SPRS score was 18.0 (SD 9.7, 0–42) and differed significantly (p<0.000) between „pure“ (15.8, SD 8.5) and „complicated“ (22.6, SD 10.4) HSP. PCS (35.1; SD 11.5) was significantly (p<0.000) lower than MCS (42.7; SD 12.6). No significant differences between „pure“ and „complicated“ HSP were found between MCS and PCS. High SPRS scores correlated significantly with low PCS (r=-.66; p<0.01) and MCS (r=-.42; p<0.01) scores.

Discussion: German HSP patients present a wide spectrum of disease severity which can be demonstrated by the broad range of SPRS results between 0 and 42 points. The influence of HSP on QoL was different between PCS and MCS. As expected, patients were more affected by the physical restraints of their disease resulting in low PCS scores. In contrast, the mental affection in the MCS was significantly less severe. Nevertheless, both the physical and mental health decrease with higher SPRS scores. Compared to a sample of 576 German MS patients (Haupts et al., 2003), the HSP patients scored lower on the PCS (MS-patients: 43.9; SD 9.9) but were similar to a subgroup of 62 more affected patients with an EDSS ≥4.0 (36.5; SD9.0). In contrast, MCS results were comparable between HSP and MS patients.

Conclusion: Health related QoL is impaired in German HSP patients depending on disease severity. This is more pronounced concerning physical aspects, whereas the mental aspects seem to be more preserved. The reduced QoL is comparable to more disabled MS patients. This study was conducted within the BMBF granted GeNeMove project. We thank the Tom-Wahlig-Stiftung and the Selbsthilfegruppe for HSP-Patients for supporting the project.