Prevalence and factors affecting glucosamine use in Korea: a survey-based study.

Glucosamine and chondroitin are widely used as pharmaceutical and dietary supplements. However, there is a lack of information regarding consumer consumption of glucosamine and chondroitin in the Republic of Korea. We investigated the prevalence and factors affecting the use of glucosamine products in the general population aged 40 years and older in the Republic of Korea. We conducted this descriptive and exploratory study using a telephone-based survey with a structured questionnaire. We randomly selected subjects using a proportional allocation method based on age, gender, and region. We started the survey on September 19, 2009, and continued the survey until we obtained 1,000 respondents who were currently taking glucosamine or chondroitin, which occured on September 30, 2009. Among the 8,135 people approached, the response rate was 29.6%. A total of 12.2% of respondents (n = 991) were current users of glucosamine, while only 0.1% (n = 9) were current users of chondroitin. Two-fifths of current glucosamine users were not diagnosed with osteoarthritis by a doctor nor did they experience arthritis pain. These participants used glucosamine to maintain and promote joint health. Information on glucosamine was mainly obtained through advertisements on television or the Internet. Seventy percent of current users indicated that they did not know the composition of the glucosamine they took. Appropriate information and guides concerning glucosamine or chondroitin usage should be provided by expert clinicians because of the accessibility of both these cartilage derivatives as supplements and medical drugs in the Republic of Korea.