Hye Jeong Kim, Ji Cheol Bae, Hyeong Kyu Park, Dong Won Byun, Kyoil Suh, Myung Hi Yoo, Jee Jae Hwan, Jae Hyeon Kim, Yong-Ki Min, Sun Wook Kim, and Jae Hoon Chung
Several cross-sectional studies have reported that thyroid hormone levels are associated with cardiovascular risk markers and metabolic syndrome (MetS) even in euthyroid subjects. However, the prognostic role of serum thyroid hormone levels in the risk of incident MetS has not been elucidated.
We aimed to investigate the associations of baseline serum thyroid hormone levels with the development of MetS in healthy subjects.
This 6-year, cross-sectional, longitudinal and follow-up study was conducted in 12 037 euthyroid middle-aged subjects without MetS subjected to comprehensive health examinations. Subjects were grouped according to total triiodothyronine (T3) quartiles. The hazard ratio (HR) for the development of MetS according to T3 quartiles was estimated using Cox proportional hazards model.
During the 6-year period, 3544 incident cases of MetS (29%) were identified. The proportion of subjects with incident MetS increased across the T3 quartiles (P for trend <0.001). The HR and 95% confidence interval (CI) for the development of MetS were significantly higher in the highest T3 quartile compared with the lowest T3 quartile even after adjusting for confounding variables including gender, age and smoking (HR: 1.238, 95% CI: 1.128–1.358, P < 0.001).
In euthyroid middle-aged subjects, serum T3 levels are associated with increased risk for future development of MetS.
Ji Eun Jun, Mira Kang, Sang-Man Jin, Kyunga Kim, You-Cheol Hwang, In-Kyung Jeong, and Jae Hyeon Kim
We aimed to investigate the interaction of reduced skeletal muscle mass and abdominal obesity on coronary artery calcification (CAC).
Design and methods
A total of 19 728 adults free of cardiovascular disease (CVD) who contemporaneously underwent cardiac tomography and bioelectrical impedance analysis were enrolled in a cross-sectional and longitudinal cohort. Skeletal muscle mass index (SMI) was calculated using the following formula: SMI (%) = total appendicular muscle mass (kg)/body weight (kg) × 100 according to sex. CAC presence or incidence was defined as CAC score > 0, and CAC progression was defined as √CAC score (follow-up) – √CAC score (baseline)>2.5. Pre-sarcopenia was defined as SMI ≤ −1.0 s.d. of the sex-specific mean of a young reference group. Abdominal obesity was defined as waist circumference ≥ 90 cm for men and ≥85 cm for women. All individuals were further classified into four groups: normal, abdominal obesity alone, pre-sarcopenia alone, and pre-sarcopenic obesity.
Individuals with pre-sarcopenic obesity showed the highest adjusted odds ratio (AOR) for CAC presence (AOR 2.16, 95% CI : 1.98–2.36, P < 0.001) as well as total CAC incidence and progression (adjusted hazard ratio: 1.54, 95% CI: 1.37–1.75, P < 0.001), compared with normal individuals. Pre-sarcopenic obesity significantly increased CAC incidence and progression compared to either pre-sarcopenia or abdominal obesity alone.
Pre-sarcopenia and abdominal obesity together were significantly associated with a higher CAC presence and increased risk of CAC incidence and progression, independent of traditional CVD risk factors.