Rheumatol Int DOI 10.1007/s00296-014-3061-8
Original Article
The effect of coffee, tea, and caffeine consumption on serum uric acid and the risk of hyperuricemia in Korean Multi‑Rural Communities Cohort Jisuk Bae · Pil Sook Park · Byung‑Yeol Chun · Bo Youl Choi · Mi Kyung Kim · Min‑Ho Shin · Young‑Hoon Lee · Dong Hoon Shin · Seong‑Kyu Kim
Received: 10 March 2014 / Accepted: 31 May 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Caffeine, a commonly consumed food constituent, is known to exert beneficial physiological effects in humans. There is a lack of comprehensive population data for the effects of caffeine intake on urate metabolism. Therefore, the aim of this study was to determine whether coffee, tea, and caffeine intake influences serum uric acid and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort. We enrolled 9,400 participants in this study. An assessment of various dietary intake amounts of substances such as coffee and tea was performed using a food frequency questionnaire. The content of caffeine was calculated from coffee (74 mg/cup) and tea (15 mg/cup) intake information from the past year. Multivariate logistic regression models, multiple linear regression models, and analysis of covariance were applied Dong Hoon Shin and Seong-Kyu Kim have contributed equally to this paper. J. Bae Department of Preventive Medicine, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea P. S. Park Department of Food and Nutrition, Kyungpook National University, Daegu, Republic of Korea B.-Y. Chun Department of Preventive Medicine, School of Medicine, Health Promotion Research Center, Kyungpook National University, Daegu, Republic of Korea B. Y. Choi · M. K. Kim Department of Preventive Medicine, College of Medicine, Hanyang University, Seoul, Republic of Korea
to identify any association of dietary intake with serum uric acid levels or the risk of hyperuricemia. No trends for coffee, tea, or caffeine intake were found according to each quintile with serum uric acid in males, although there were weak, marginally significant trends between the content of coffee and caffeine intake and serum uric acid level in females (p = 0.07 for both). Tea intake in males and caffeine intake in females were significantly different between non-hyperuricemia and hyperuricemia (p = 0.04 and p = 0.04, respectively). In addition, a significant association of serum uric acid level with tea intake in males (β = 0.0006, p = 0.02) and with tea intake and caffeine intake in females (β = 0.0003, p = 0.04 and β = 0.0006, p = 0.02, respectively) was observed. There was no effect of coffee, tea, or caffeine intake on the risk of hyperuricemia in either males or females. This study suggests that caffeine consumption might have an effect Y.-H. Lee Department of Preventive Medicine, Institute of Wonkwang Medical Science, Wonkwang University College of Medicine, Iksan, Jeonlabuk‑do, Republic of Korea D. H. Shin (*) Department of Preventive Medicine, School of Medicine Keimyung University, 194 Dong San‑Dong, Jung‑Gu, Daegu 700‑712, Republic of Korea e-mail: [email protected] S.-K. Kim (*) Division of Rheumatology, Department of Internal Medicine, Arthritis and Autoimmunity Research Center, Catholic University of Daegu School of Medicine, 33, Duryugongwon‑ro 17‑gil, Nam‑gu, Daegu 705‑718, Republic of Korea e-mail: [email protected]
M.-H. Shin Department of Preventive Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
13
on serum uric acid in females. However, coffee, tea, and caffeine intake amounts were not associated with the risk of hyperuricemia.
Rheumatol Int
Keywords Uric acid · Hyperuricemia · Coffee · Tea · Caffeine
consumption on serum uric acid levels in the Asian population. This cross-sectional study identified the effect of caffeine intake and caffeine-containing beverage consumption, including coffee and tea, on serum uric acid level and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort.
Introduction
Subjects and methods
Uric acid is an oxidative by-product of xanthine generated from the metabolism of endogenous and exogenous purines [1]. Exogenous sources of purine include purine-rich foods and high caloric diets such as meat, fructose-containing soft drinks, and alcoholic drinks. Some of these dietary factors contribute to increased serum uric acid levels and ultimately lead to the development of gout, which is characterized by gouty arthritis, urate-induced renal functional impairment, and urate renal stones occurring in long-standing hyperuricemic patients [2]. The mechanisms for the development of increased serum uric acid and a hyperuricemic state could be related to an abundant input of uric acid that exceeds its excretion. Caffeine (1,3,7-trimethylxanthine) is widely consumed and ubiquitously present in humans from dietary intake of coffee, tea, energy drinks, and chocolate products [3, 4]. Evidence has demonstrated that moderate caffeine consumption can exert beneficial health effects, including mental alertness, physical performance, and increased tolerance to fatigue [5]. However, the excessive intake of caffeine might also be associated with adverse effects, such as anxiety, restlessness, and an increased risk of hypertension. Previous data on caffeine intake or caffeine-containing beverage consumption for serum uric acid level, hyperuricemia, and the incidence of gout have been reported by clinical trials and epidemiological research studies [6–12, 17]. These authors focused on the association between caffeinated beverages such as coffee and tea and serum uric acid levels. The results of most studies demonstrated that frequent coffee intake might reduce serum uric acid levels [8, 9, 12, 17] and therefore decrease the incidence of gout [10, 11]. In contrast, the intake of green tea or coffee was found to be associated with a higher level of serum uric acid [6, 7]. Regarding the effect of caffeine on uric acid, two epidemiological observations suggested no association existed between caffeine intake and serum uric acid level in the US population [9, 11]. However, an inverse correlation was noted between caffeine intake and the risk of gout in the Nurses’ Health Study [10]. In fact, caffeine intake could be significantly variable due to its sources being from different types of caffeine-containing beverages and also according to the study population [3, 4]. There is still a lack of comprehensive population-based data on the effect of caffeine
Study population
13
The population in this study was recruited from the Korean Multi-Rural Communities Cohort Study in Rural Communities, which was multicenter prospective cohort. The population was aged ≥40 years at enrollment from three rural areas, Yangpyeong, Namwon, and Goryeong in Republic of Korea. The total number of recruited subjects in the cohort was 9,697 from January 2005 to August 2009. This study excluded those with missing data for serum uric acid level and other food items. A total of 9,400 subjects were finally analyzed for this study. This study was performed according to the guidelines of the Declaration of Helsinki. The Institutional Review Boards of Hanyang University, Chonnam National University, and Keimyung University approved the protocol of the study. Assessment of clinical information Baseline characteristics for study population included age, gender, education, marital status, medication history (i.e., anti-hypertensive medication), and lifestyle factors such as cigarette smoking, alcohol consumption, and physical activity. The data collection was performed using standardized protocols for questionnaire survey and examination procedures by well-trained research assistants. Data for body measurements (i.e., height, weight, waist circumference, and systolic and diastolic blood pressures) and laboratory parameters [i.e., uric acid, creatinine, triglyceride, high-density lipoprotein (HDL) cholesterol, and fasting serum glucose] were assessed. Body mass index (BMI, kg/m2) was also calculated. Laboratory parameters from blood samples obtained in the overnight fasting state were measured at same day by the ADVIA 1800 Auto Analyzer (Simens Medical Solutions, Malvern, PA, USA). Glomerular filtration rate (GFR) was determined using the simplified equation of the Modification of Diet in Renal Disease Study [13]. Assessment of dietary factors This study performed assessment of dietary intake using a semi-quantitative food frequency questionnaire (FFQ),
Rheumatol Int
which was already validated [14]. FFQ is composed of the average frequency (nine categories ranging from ‘never or rare’ to ‘three times per day’) and portion size (three specified portion sizes) of consumption of 106 food items over the past year. Each subject was also asked to mark one of the following four duration categories: three, six, nine, and 12 months regarding the consumption of seasonal food items. The average daily intakes of each food item (i.e., intakes of coffee, tea, meat, seafood, dairy food, soft drink, and added sugar and cream in coffee) were estimated using the weighted frequency per day and the portion size per unit of each food item. Caffeine intake was determined by the consumption of coffee and tea over the past year. Using data from the Korea Ministry of Food and Drug Safety [15], we estimated that the caffeine content was 74 mg per cup of coffee (per 2.7 g) and 15 mg per cup of tea (per 120 mL). In order to convert intakes of food items into nutrients (i.e., total energy and vitamin C), we used the seventh edition of the Food Composition Table, a nutrient database produced by the Korean Nutrition Society [16]. Statistical analysis Data were expressed as mean ± standard deviation (SD) for continuous variables and frequency and percentage for categorical variables in comparison with baseline characteristics. Student’s t tests were used to compare the mean differences between two groups. Chi-square tests were used to assess the differences in proportions between two groups. We conducted analyses separately for males and females. Hyperuricemia was defined as serum uric acid levels >7.0 mg/dL in males and >6.0 mg/dL in females. Coffee intake (
Original Article
The effect of coffee, tea, and caffeine consumption on serum uric acid and the risk of hyperuricemia in Korean Multi‑Rural Communities Cohort Jisuk Bae · Pil Sook Park · Byung‑Yeol Chun · Bo Youl Choi · Mi Kyung Kim · Min‑Ho Shin · Young‑Hoon Lee · Dong Hoon Shin · Seong‑Kyu Kim
Received: 10 March 2014 / Accepted: 31 May 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Caffeine, a commonly consumed food constituent, is known to exert beneficial physiological effects in humans. There is a lack of comprehensive population data for the effects of caffeine intake on urate metabolism. Therefore, the aim of this study was to determine whether coffee, tea, and caffeine intake influences serum uric acid and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort. We enrolled 9,400 participants in this study. An assessment of various dietary intake amounts of substances such as coffee and tea was performed using a food frequency questionnaire. The content of caffeine was calculated from coffee (74 mg/cup) and tea (15 mg/cup) intake information from the past year. Multivariate logistic regression models, multiple linear regression models, and analysis of covariance were applied Dong Hoon Shin and Seong-Kyu Kim have contributed equally to this paper. J. Bae Department of Preventive Medicine, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea P. S. Park Department of Food and Nutrition, Kyungpook National University, Daegu, Republic of Korea B.-Y. Chun Department of Preventive Medicine, School of Medicine, Health Promotion Research Center, Kyungpook National University, Daegu, Republic of Korea B. Y. Choi · M. K. Kim Department of Preventive Medicine, College of Medicine, Hanyang University, Seoul, Republic of Korea
to identify any association of dietary intake with serum uric acid levels or the risk of hyperuricemia. No trends for coffee, tea, or caffeine intake were found according to each quintile with serum uric acid in males, although there were weak, marginally significant trends between the content of coffee and caffeine intake and serum uric acid level in females (p = 0.07 for both). Tea intake in males and caffeine intake in females were significantly different between non-hyperuricemia and hyperuricemia (p = 0.04 and p = 0.04, respectively). In addition, a significant association of serum uric acid level with tea intake in males (β = 0.0006, p = 0.02) and with tea intake and caffeine intake in females (β = 0.0003, p = 0.04 and β = 0.0006, p = 0.02, respectively) was observed. There was no effect of coffee, tea, or caffeine intake on the risk of hyperuricemia in either males or females. This study suggests that caffeine consumption might have an effect Y.-H. Lee Department of Preventive Medicine, Institute of Wonkwang Medical Science, Wonkwang University College of Medicine, Iksan, Jeonlabuk‑do, Republic of Korea D. H. Shin (*) Department of Preventive Medicine, School of Medicine Keimyung University, 194 Dong San‑Dong, Jung‑Gu, Daegu 700‑712, Republic of Korea e-mail: [email protected] S.-K. Kim (*) Division of Rheumatology, Department of Internal Medicine, Arthritis and Autoimmunity Research Center, Catholic University of Daegu School of Medicine, 33, Duryugongwon‑ro 17‑gil, Nam‑gu, Daegu 705‑718, Republic of Korea e-mail: [email protected]
M.-H. Shin Department of Preventive Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
13
on serum uric acid in females. However, coffee, tea, and caffeine intake amounts were not associated with the risk of hyperuricemia.
Rheumatol Int
Keywords Uric acid · Hyperuricemia · Coffee · Tea · Caffeine
consumption on serum uric acid levels in the Asian population. This cross-sectional study identified the effect of caffeine intake and caffeine-containing beverage consumption, including coffee and tea, on serum uric acid level and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort.
Introduction
Subjects and methods
Uric acid is an oxidative by-product of xanthine generated from the metabolism of endogenous and exogenous purines [1]. Exogenous sources of purine include purine-rich foods and high caloric diets such as meat, fructose-containing soft drinks, and alcoholic drinks. Some of these dietary factors contribute to increased serum uric acid levels and ultimately lead to the development of gout, which is characterized by gouty arthritis, urate-induced renal functional impairment, and urate renal stones occurring in long-standing hyperuricemic patients [2]. The mechanisms for the development of increased serum uric acid and a hyperuricemic state could be related to an abundant input of uric acid that exceeds its excretion. Caffeine (1,3,7-trimethylxanthine) is widely consumed and ubiquitously present in humans from dietary intake of coffee, tea, energy drinks, and chocolate products [3, 4]. Evidence has demonstrated that moderate caffeine consumption can exert beneficial health effects, including mental alertness, physical performance, and increased tolerance to fatigue [5]. However, the excessive intake of caffeine might also be associated with adverse effects, such as anxiety, restlessness, and an increased risk of hypertension. Previous data on caffeine intake or caffeine-containing beverage consumption for serum uric acid level, hyperuricemia, and the incidence of gout have been reported by clinical trials and epidemiological research studies [6–12, 17]. These authors focused on the association between caffeinated beverages such as coffee and tea and serum uric acid levels. The results of most studies demonstrated that frequent coffee intake might reduce serum uric acid levels [8, 9, 12, 17] and therefore decrease the incidence of gout [10, 11]. In contrast, the intake of green tea or coffee was found to be associated with a higher level of serum uric acid [6, 7]. Regarding the effect of caffeine on uric acid, two epidemiological observations suggested no association existed between caffeine intake and serum uric acid level in the US population [9, 11]. However, an inverse correlation was noted between caffeine intake and the risk of gout in the Nurses’ Health Study [10]. In fact, caffeine intake could be significantly variable due to its sources being from different types of caffeine-containing beverages and also according to the study population [3, 4]. There is still a lack of comprehensive population-based data on the effect of caffeine
Study population
13
The population in this study was recruited from the Korean Multi-Rural Communities Cohort Study in Rural Communities, which was multicenter prospective cohort. The population was aged ≥40 years at enrollment from three rural areas, Yangpyeong, Namwon, and Goryeong in Republic of Korea. The total number of recruited subjects in the cohort was 9,697 from January 2005 to August 2009. This study excluded those with missing data for serum uric acid level and other food items. A total of 9,400 subjects were finally analyzed for this study. This study was performed according to the guidelines of the Declaration of Helsinki. The Institutional Review Boards of Hanyang University, Chonnam National University, and Keimyung University approved the protocol of the study. Assessment of clinical information Baseline characteristics for study population included age, gender, education, marital status, medication history (i.e., anti-hypertensive medication), and lifestyle factors such as cigarette smoking, alcohol consumption, and physical activity. The data collection was performed using standardized protocols for questionnaire survey and examination procedures by well-trained research assistants. Data for body measurements (i.e., height, weight, waist circumference, and systolic and diastolic blood pressures) and laboratory parameters [i.e., uric acid, creatinine, triglyceride, high-density lipoprotein (HDL) cholesterol, and fasting serum glucose] were assessed. Body mass index (BMI, kg/m2) was also calculated. Laboratory parameters from blood samples obtained in the overnight fasting state were measured at same day by the ADVIA 1800 Auto Analyzer (Simens Medical Solutions, Malvern, PA, USA). Glomerular filtration rate (GFR) was determined using the simplified equation of the Modification of Diet in Renal Disease Study [13]. Assessment of dietary factors This study performed assessment of dietary intake using a semi-quantitative food frequency questionnaire (FFQ),
Rheumatol Int
which was already validated [14]. FFQ is composed of the average frequency (nine categories ranging from ‘never or rare’ to ‘three times per day’) and portion size (three specified portion sizes) of consumption of 106 food items over the past year. Each subject was also asked to mark one of the following four duration categories: three, six, nine, and 12 months regarding the consumption of seasonal food items. The average daily intakes of each food item (i.e., intakes of coffee, tea, meat, seafood, dairy food, soft drink, and added sugar and cream in coffee) were estimated using the weighted frequency per day and the portion size per unit of each food item. Caffeine intake was determined by the consumption of coffee and tea over the past year. Using data from the Korea Ministry of Food and Drug Safety [15], we estimated that the caffeine content was 74 mg per cup of coffee (per 2.7 g) and 15 mg per cup of tea (per 120 mL). In order to convert intakes of food items into nutrients (i.e., total energy and vitamin C), we used the seventh edition of the Food Composition Table, a nutrient database produced by the Korean Nutrition Society [16]. Statistical analysis Data were expressed as mean ± standard deviation (SD) for continuous variables and frequency and percentage for categorical variables in comparison with baseline characteristics. Student’s t tests were used to compare the mean differences between two groups. Chi-square tests were used to assess the differences in proportions between two groups. We conducted analyses separately for males and females. Hyperuricemia was defined as serum uric acid levels >7.0 mg/dL in males and >6.0 mg/dL in females. Coffee intake (
