Selected health and lifestyle factors, cytosine‐adenine‐guanine status, and phenoconversion in Huntington's disease

Background: In Huntington's disease, 60% of the variance in onset age is not explained by the huntingtin gene mutation. Huntington's disease onset was earlier in caffeine users. Objective: The objective of this study was to assess the relationship of lifestyle factors with motor phenoconversion among persons at risk for Huntington's disease. Methods: The associations of motor phenoconversion and exposure to selected lifestyle and health factors were examined using Cox proportional hazards analyses adjusted for age, gender, and repeat length. Results: Of 247 participants, 36 (14.6%) phenoconverted. Mean follow‐up was 4.2 years. Greater caffeinated soda use was associated with an increased hazard of phenoconversion: moderate use hazard ratio 2.26 (95% confidence interval 0.59‐8.71), high use hazard ratio 4.05 (95% confidence interval 1.18‐13.96). Conclusions: Huntington's disease onset was earlier among consumers of caffeinated soda, but not other caffeinated beverages. This finding may be spurious or not related to caffeine. © 2018 International Parkinson and Movement Disorder Society