Analysis of correlation between the consumption of beverages and the risk of radiographic knee osteoarthritis in Korean people: A cross-sectional study using the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-1, 2)

Lim CO, Park HJ, Koo BM, Kim BT, Kim JG, Choi GW · Medicine (Baltimore)

Soft drinks, green tea and milk showed no significant relationship with radiographic knee OA in either sex. The only association was coffee, inversely, in women only: adjusted odds ratio 0.65 (95% CI 0.45-0.94) for any coffee and 0.60 (0.41-0.89) for daily coffee against none, p for trend 0.03 — which points the opposite way from the Mendelian randomization literature on coffee.

Population

5,503 adults aged 50 and over (2,314 men, 3,189 women) in the Fifth Korea National Health and Nutrition Examination Survey with knee radiographs, 41% with Kellgren-Lawrence grade 2 or worse

Intervention

Frequency of drinking coffee, green tea, milk or soft drinks

Comparator

Non-drinkers of each

Limitations

Cross-sectional national survey data, beverage frequency by questionnaire, prevalent radiographic disease. A single-sex association among eight tested beverage-sex combinations is what multiple comparisons produce. Daily soft-drink drinkers were 0.56% of men and 0.34% of women, so the soft-drink null is a test with almost no exposed people, which the authors say themselves. No funding or conflicts declared.