The impact of lifetime coffee and tea loads on Multiple Sclerosis severity

Abstract

Background and aims: The association between lifestyle factors and Multiple Sclerosis (MS) disease severity and progression has been investigated to a lesser extent compared with susceptibility to the disease. We aimed to assess the impact of lifetime coffee and tea consumption on MS severity.

Methods: Design: cross-sectional study. Two hundred and eight patients (139 females and 69 males) consecutively recruited at the Department of Neurology in Novara, Italy were asked about their lifetime consumption of coffee and tea. The lifetime intensity of consumption (cups/day) was estimated as the weighted sum of the mean number of standard cups drunk per day at different ages. A measure of cumulative lifetime load of the exposure was expressed in terms of cup-years. Disease severity was estimated by the Multiple Sclerosis Severity Score (MSSS). HLA-DRB1∗15 and HLA-A∗02 genotyping was performed in 167 patients.

Results: The MSSS was not associated with the status of coffee or tea consumer, or the amount of cups/day or cup-years. The Odds Ratios (OR) for falling in the upper tertile of the MSSS distribution was 1.30 (95% Confidence Interval (CI): 0.47-3.58) for coffee consumers of 1-3 cups/day and 1.14 (95%CI: 0.33-3.95) for 4-8 cups/day vs. non-consumers. The OR was 0.69 (95%CI: 0.35-1.34) for tea consumers vs. non-consumers. However, heavy consumers of coffee (4-8 cups/day) more frequently had a progressive form than small consumers (1-3 cups/day) and non-consumers (19% vs. 14% vs. 0%), and had a significantly higher age at MS onset (36.6 ± 10.3; 31.5 ± 9.5; 28.6 ± 8.1 years, p = 0.001). Although not reaching statistical significance, coffee consumers positive for HLA-A∗02 had a six-fold risk of being in the worst tertile compared to never consumers, whereas the risk was only 1.3 for coffee consumers negative for the same allele.

Conclusions: Coffee or tea intake is not associated with different severity of MS. However, we cannot exclude a possible effect of higher doses of coffee for the subgroup of progressive patients.

Keywords: Coffee; Cross-sectional study; HLA; Multiple Sclerosis; Risk factors; Tea.