[Association of abdominal fat distribution by computed tomography with body mass index and metabolic syndrome in Chinese elders].

OBJECTIVE: To explore the gender and age difference of abdominal fat distribution in Chinese older adults and examine the effects of metabolic syndrome (MS) on abdominal fat distribution by computed tomography (CT).

METHODS: Chinese elders (aged ≥ 65 years old) undergoing abdominal CT scanning at our hospital from January 2009 to December 2010 were collected through retrospective analysis. A total of 52 healthy normal-weight subjects and gender-specific body mass index (BMI)-matched middle-aged adults were selected (28 males, 24 females) to compare the difference of abdominal fat during the same period. Visceral fat area (VFA) and subcutaneous fat area (SFA) were measured at the cross-sections of L4 and L5 intervertebral space.

RESULTS: A total of 390 subjects were enrolled. There were 252 males and 138 females. Total abdominal fat (TAF) was not significantly different in both genders [female (323 ± 122 cm²) vs male (303 ± 141 cm²) , P = 0.146]. However, females had higher TAF than males after height correction (128 ± 49 vs 105 ± 49 cm²/m², P = 0.000). VFA and SFA were higher with higher BMI values across lean, normal weight, overweight and obese groups in both genders. VFA and SFA were not significantly different in both genders among 3 different age groups (>65-75, >75-85, >85 years; P > 0.05). Compared with healthy normal weight elders and BMI-matched middle-aged adults, VFA and SFA increased with more components of MS except in only one component group. When the patients were excluded suffering from 2 or more components of MS, VFA was not significantly different between normal weight elders and those with only one component of MS (diabetes/hyperlipidemia/hypertension). Logistic regression analysis showed VFA was a risk factor for elders with MS (male: OR = 1.03, 95%CI: 1.012- 1.047; female: OR = 1.06, 95%CI: 1.026-1.088) . However, SFA and age were not.

CONCLUSIONS: The elder females have more TAF than the elder males while abdominal fat does not increase with age in elders. TAF, VFA and SFA have a highly positively correlation with BMI. Visceral fat, not subcutaneous fat, is a risk factor for elders with MS and it increases with an increment of more than 2 components of MS.