The sense-of-coherence predicts health-related quality of life and emotional distress but not disability in Parkinson’s disease

BACKGROUND Personality traits are deemed important in many fields of Medicine. The present study aimed at evaluating i) the presence of Sense-of-Coherence (SOC) in patients suffering from Parkinson's Disease (PD) in comparison with an age-matched general control population, ii) the influence of SOC on health-related variables, such as depression and anxiety, quality of life (Qol), and activities of daily living (ADL). METHODS SOC was measured in 50 PD patients and in 50 matched controls enrolled in cross-sectional study. The other clinical measures included: Mini Mental State Examination (MMSE), Movement Disorder Society revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS), Well-being Index (WHO-5), Hospital Anxiety and Depression Scale (HADS) and the Barthel Index of ADL (BI). Data were analysed with univariate statistics and loglinear adjusted regression models. RESULTS No difference emerged between PD and controls on socio-demographic and SOC. A statistically significant positive correlation was found between SOC and Qol (0.40, p < 0.004) and a negative significant correlation between SOC and emotional distress (-0.37, p < 0.008). The multivariate regression analysis confirmed the negative effect of SOC on total emotional distress (-3%, p = 0.01) and positive effect on Qol (2%, p = 0.01). SOC and BI were uncorrelated. CONCLUSIONS SOC is predictive of QoL and emotional distress in PD, whereas no evidence of a predictive effect for disability could be found. These results support only partially, the Salutogenic Theory in PD, i.e. a strong SOC positively influences psychosocial health, but does not influence physical health.