FM2-3 Slave to the rhythm: seasonal differences in non-motor symptoms in parkinson’s

Objectives To determine the effect of the change of season on non-motor symptoms in Parkinson’s disease (PD). Design Cross-sectional retrospective study. Subjects 364 consecutive Parkinson’s patients in the London area taking part in the Non-motor Longitudinal International Study (NILS) study at King’s College Hospital London between November 2011 and April 2018. Methods Participants were divided into three groups based on their assessment date, using a simplified ecological seasonal model: November until February; March until 15 June; 16 June until October. The primary outcome was a seasonal difference in non-motor symptom scale (NMSS) total scores and the secondary outcomes were NMSS subscores. Outcomes were adjusted for multiple testing using formal Bonferroni correction. Results 102 patients were allocated to group 1, 105 patients to group 2 and 157 patients to group 3. Seasonal differences were present in NMSS total scores (p=0.042), especially between groups 1 and 3 (p=0.037). Differences were also present for NMSS domain 1 (cardiovascular and falls; p=0.004), 2 (sleep and fatigue; p=0.049), 4 (hallucinations; p=0.003) and 9 (miscellaneous; p=0.031). Within domain 9 there was only a significant difference for question 28 (smell; p=0.008). Conclusions These results indicate that non-motor symptoms in Parkinson’s fluctuate throughout the year with lowest scores in the summer months and highest in the winter months. These variations need to be taken into account to avoid inappropriate changes in medication regimes.