Consumption of tea increases risk of Rheumatoid Arthritis in women

Association between coffee consumption and RA not found

Women who drink tea have an increased risk of developing Rheumatoid Arthritis (RA) compared with those who drink none.

The results of the US based longitudinal cohort study involving 76,643 women showed a positive association of incident RA in tea drinkers with an increasing Hazard Ratio (HR) observed alongside tea consumptions own healthy cells and tissues.

"We set out to determine whether tea or coffee consumption, or the method of preparation of the drinks was associated with an increased risk of RA or SLE - it is surprising that we saw such differences in results between tea and coffee drinkers," said Professor Christopher Collins, Assistant Professor of Medicine, Georgetown University Medical Center, Washington, USA. "This does make us wonder what it is in tea, or in the method of preparation of tea that causes the significant increase in risk of developing RA."

Data on women aged 50-79 were taken from the Women's Health Initiative Observational Study database (a major 15-year research program to address the most common causes of death, disability and poor quality of life in postmenopausal women) where participants completed a self-administered questionnaire providing information on daily consumption of coffee and tea.

The relationships between drinking tea and coffee and the risk of RA or SLE were assessed in age-adjusted models and in multivariate Cox proportional hazard models (a statustical approach to estimating survival data). At three years follow up, the diagnosis of incident RA was determined using self-reporting and respondent's feedback on use of disease modifying anti-rheumatic drugs (DMARDS). The variables studied in the RA population were also investigated in women with SLE, but no significant associations were found.

"These are very interesting findings and we hope that additional research will investigate this topic further. We do assert the need for caution in the interpretation of these findings as no strong causation effect has been confirmed, and encourage patients with rheumatic diseases to consult their physician before making any significant changes to their diet or caffeine intake" said Professor Paul Emery, President of EULAR and arc Professor of Rheumatology, Leeds Institute of Molecular Medicine, University of Leeds, UK