Objective: To characterize nutritional status (body weight, body mass index [BMI]), dietary habits, and lifestyle factors (smoking) of twins discordant for Parkinson’s disease (PD).

Background: Previous studies suggest environmental and behavioral factors, in addition to genetic predisposition, contribute to PD pathophysiology.Twins, particularly monozygotic ones, sharing many important early-life events and life-course factors, offer a unique model for exploring the role of environmental and behavioral factors independently of a genetic predisposition. Modifiable lifestyle risk factors could represent a target for prevention.

Method: Fifty-four twin pairs discordant for idiopathic PD were recruited through a national campaign. Zygosity (monozygotic [MZ]/dizygotic [DZ]) was determined by genetic testing. Anthropometric assessment: body weight, height and BMI. Lifestyle factors (smoking and dietary habits) were investigated using structured questionnaires, while nutrient intake by means of food diaries was analyzed using WinFood software. Clinical evaluation focused on the presence of constipation and metabolic disorders. Paired-data analysis addressed two groups: all discordant twin pairs (n=54); MZ twin pairs (n=26).

Results: In our cohort (mean age±SD 66.2±10.8 years; men 55.5%), body weight and BMI did not differ between patients and controls regardless of zygosity. Active smoking was reported in 7.4% of cases vs 14.8% of healthy twins (p=0.22), and former smoking in 25.9% vs 22.2% (p=0.75), with similar distribution in MZ twins. Dietary analysis showed a significant difference in preserved fish consumption in all pairs (p=0.021) and MZ twins (p=0.041). Added sugars showed a borderline difference in all pairs (p=0.050), while low fruit intake was significant in MZ twins (p=0.001). Constipation prevalence was higher in cases (p=0.004). Non-neurological comorbidities were comparable.

Conclusion: The nutritional features, the dietary habits and the lifestyle substantially overlap in twins discordant for PD but the higher prevalence of constipation in cases supports the hypothesis of early gut–brain axis involvement. However, the cross-sectional design limits the inference for a cause-effect relationship of the differences detected. Further prospective investigations are needed in this area.

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MDS Abstracts - https://www.mdsabstracts.org/abstract/nutritional-status-clinical-features-and-lifestyle-of-twins-discordant-for-parkinsons-disease/