Mediterranean diet and essential tremor: A case-control study

Background: Higher adherence to the Mediterranean diet (MeDi) has been related to lower Alzheimer's disease risk. Some dietary factors have been studied in patients with essential tremor (ET), but the MeDi's effect has not been investigated. Methods: Adherence to the MeDi was calculated from a food frequency questionnaire administered in a case-control study of environmental epidemiology of ET in the New York Tri-State area. Logistic regression models were used to examine whether adherence to the MeDi predicted ET (vs. control) outcome. The models adjusted for age, gender, ethnicity, education, caloric intake, body mass index, smoking, ethanol consumption, coffee intake and blood harmane concentrations. Results: 148 ET cases adhered less to MeDi (0-9 scale with higher scores indicating higher adherence) than 250 controls (mean 4.3 ± 1.7 vs. 4.7 ± 1.7; p = 0.03). Higher adherence to MeDi was associated with lower odds for ET [0.78 (0.61-0.99); p = 0.042]. As compared to subjects at the lowest MeDi adherence tertile, those at the middle tertile had lower ET odds [0.41 (0.16-1.05)], while subjects at the highest tertile had an even lower ET odds [0.29 (0.10-0.82); p for trend 0.021]. Conclusions: Compared to controls, ET cases adhered less to MeDi. The gradual reduction in ET odds with higher MeDi adherence tertiles suggests a possible dose-response effect. The mechanisms that underlie this association merit further study.