Characteristics of metabolic factors related to arterial stiffness in young and old adults.

It has not been adequately studied which biomarkers for cardiovascular risk indicate changes of atherosclerosis by aging process. The current study aimed to investigate the characteristics of metabolic factors related to arterial stiffness in young and old adults. Our cross-sectional study enrolled 851 healthy young adults and 719 old adults. Metabolic biomarkers included glucose, lipid profiles, and liver enzymes. In young adults, additional biomarkers such as C-reactive protein, apolipoproteins, lipoprotein(a), ferritin, and 25-hydroxycholecalciferol were measured. Arterial stiffness was evaluated by measuring brachial-ankle pulse wave velocity (baPWV). The mean age was 37.8 and 65.1 years old in the young and old groups, respectively. Without adjustment, most parameters were significantly correlated with baPWV in both young and old groups. Mean baPWV was significantly different according to metabolic syndrome (MetS) in both groups (13.1 and 12.1 m/s in the young subjects with and without MetS, respectively; 17.4 and 15.8 m/s, respectively, in the old group). After adjusting for age, sex, and hemodynamic factors, the difference in baPWV according to MetS was significant only in the old group. The relationship between most biomarkers and baPWV was influenced by metabolic disorders such as hypertension and diabetes in old adults. Total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), and apolipoprotein B were significant in young group. In conclusion, the metabolic biomarkers related to arterial stiffness were different between young and old adults. Contrary to old adults, TC, LDLC, and apolipoprotein B were independent biomarkers for arterial stiffness in healthy young adults.

Total testosterone may not decline with ageing in Korean men aged 40 years or older.

OBJECTIVE: It is generally believed that gonadal function in men declines with ageing. However, observations on ageing-related decrease in total testosterone (TT) are not consistent. The aim of this study is to examine the ageing-related changes of testosterone and to investigate the influence of the ageing-related factors on TT. DESIGN: Changes of TT with ageing were observed in longitudinal design in a single health promotion centre. SUBJECTS: A total of 220 Korean men aged ≥40 years were included between 2002 and 2011. TT assay was repeated for all subjects, with an interval of ≥3 years. MEASUREMENTS: Information of medical history and lifestyle habits was collected. Anthropometry and blood pressure were measured. TT, glucose, creatinine, highly sensitive C-reactive protein, liver enzymes and lipid profiles were tested. RESULTS: Mean TT level did not decline significantly with ageing during median 4·3 years follow-up (18·1 vs 17·8 nm, P = 0·439). Longitudinal change of TT was approximately + 0·8% per year. TT was negatively correlated with body mass index (BMI), waist circumference and glucose. With mixed effects model, diabetes (P = 0·038) and BMI (P = 0·007) affected TT level, but age and follow-up interval did not. CONCLUSIONS: TT did not change significantly in 220 Korean men for a median 4·3 years follow-up. TT was not influenced by the age and follow-up interval. BMI and diabetes mellitus affected TT decline.

Bowel preparation for colonoscopy may decrease the levels of testosterone in Korean men.

Although colonoscopy is commonly conducted for medical check-ups in Korea, investigations for the influence of bowel preparation on various health conditions are insufficient. This cross-sectional study investigated whether bowel preparation has an influence on serum levels of testosterone. A total of 1114 men were divided into the bowel preparation group and control groups. The median total and free testosterone levels were significantly lower in the bowel preparation group (14.89 and 0.26 nmol/L, respectively) than in the control groups (15.72 and 0.28 nmol/L, respectively). The level of total testosterone significantly increased with age in the bowel preparation group (r = 0.103). The differences in the levels of total and free testosterone between the 2 groups were more prominent in younger men than in older men. In multivariate regression models, bowel preparation was independently associated with the levels of total and free testosterone. In these models, the interaction between age and bowel preparation was significant for the levels of total and free testosterone. In conclusion, bowel preparation may independently decrease the serum levels of total and free testosterone. The decline in testosterone was more evident in younger men than in older men.

Hair mercury level in smokers and its influence on blood pressure and lipid metabolism.

OBJECT: Smoking is a major risk factor for the development and progression of cardiovascular disease and cigarettes contain a slight amount of mercury. Mercury has been causally linked to cardiovascular diseases. This study evaluated the mercury content in hair according to smoking exposure status and the influence of the mercury level on blood pressure and lipid metabolism. METHODS: We examined mercury concentration in the hair samples from 236 healthy people 16-75-years-of-age who had visited the health promotion center of a university hospital from January 2004 to January 2007. Self-reported cigarette smoking status and baseline health information were obtained using a questionnaire. Blood pressure and serum lipid level according to the mercury concentration were assessed. RESULTS: The mean systolic blood pressure in the smoking exposure group and non-exposure group were 123.2±15.4mmHg and 117.2±15.9mmHg, respectively (p=0.005). The mean diastolic pressure in the smoking exposure group and non-exposed group were 80.2±10.9mmHg and 75.1±11.3mmHg, respectively (p<0.001). Mercury concentration had a positive relationship with systolic and diastolic blood pressure. Compared with the normal and high mercury groups, the normal mercury group demonstrated lower blood pressure, lower triglyceride, and lower smoking amount, but higher high density lipoprotein cholesterol than the high mercury group. There was an increase of mercury concentration in the smoking exposure group. The 20-29 packyear group showed significantly increased odds ratio of mercury content, compared with the non-exposure group (14.00, 95% confidence interval, 5.03-38.96). CONCLUSIONS: Smoking is positively associated with mercury accumulation, and high mercury concentration is associated with increased blood pressure and abnormal lipid metabolism.

Total testosterone and sex hormone-binding globulin are associated with metabolic syndrome independent of age and body mass index in Korean men.

OBJECTIVE: The purpose of this study is to investigate the relationship between sex hormones and metabolic syndrome independent of age and BMI in Korean men. STUDY DESIGN: We conducted a cross-sectional study with data from a health promotion center during the period from March 2007 to February 2010. 2172 Korean men aged 21-79 were enrolled. Total testosterone, sex hormone-binding globulin (SHBG), high density lipoprotein (HDL) cholesterol, triglyceride (TG), and glucose were assessed with overnight fasting serum samples. MAIN OUTCOME MEASURES: Sex hormones were divided into quartiles; odds ratios for metabolic syndrome and each component were analyzed. RESULTS: Total testosterone showed negative associations with waist circumference (WC), fasting glucose, TG, blood pressure and body mass index (BMI), and a positive relationship with HDL cholesterol (P for trend <0.001, respectively). SHBG was negatively associated with WC, fasting glucose, TG, and BMI, and positively associated with total testosterone and age. Comparing with the highest quartile, odds ratios of lowest quartile of total testosterone and SHBG for metabolic syndrome were 3.01 (95% CI, 2.11-4.28) and 6.34 (95% CI, 2.29-17.58), respectively, after adjusting for age, smoking status, alcohol intake, exercise, and BMI. Total testosterone was significantly associated with each metabolic component and SHBG was associated with glucose and TG after adjustment for age, smoking status, alcohol intake, and BMI. Calculated free testosterone had no significant relationship with metabolic syndrome or its components. CONCLUSION: Total testosterone and SHBG are negatively associated with prevalence of metabolic syndrome independent of age and BMI in Korean men.

Prevalence of sarcopenia and sarcopenic obesity in the Korean population based on the Fourth Korean National Health and Nutritional Examination Surveys.

BACKGROUND: Sarcopenia is an important factor of functional impairment related to aging. This study is conducted to investigate the prevalence of sarcopenia and sarcopenic obesity in Korean population. METHODS: Representative Korean men (4,486) and women (5,999) aged 20 years or older were analyzed from the Fourth Korean National Health and Nutritional Examination Surveys. Sarcopenia was classified into Class I defined relative skeletal muscle mass loss within 1-2 SD of the gender-specific mean for healthy young adults and Class II below 2 SD. Relative skeletal muscle mass was represented by the appendicular skeletal muscle mass adjusted by height and body weight. Sarcopenic obesity was considered present in Class II sarcopenic participants whose waist circumference was more than or equal to 90 cm for men and more than or equal to 85 cm for women, respectively. RESULTS: The prevalence of Class II sarcopenia in the Korean elderly population was 12.4% for men and 0.1% for women by height-adjusted definition and 9.7% for men and 11.8% for women by weight-adjusted definition. The prevalence of sarcopenic obesity was 7.6% for men and 9.1% for women by weight-adjusted definition but nearly zero for men and women by height-adjusted definition. The prevalence of sarcopenia increased with age for men but for women only when applied with weight-adjusted definition. CONCLUSIONS: The prevalence of sarcopenia and sarcopenic obesity differs by gender and definition criteria. The height-adjusted definition may tend to underestimate the prevalence of sarcopenia and sarcopenic obesity, especially in women.