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DESIGN: Cohort study.
SETTING: The unique disability-focused National Long Term Care Survey (NLTCS) data that assessed the health and well-being of older individuals in 1994 were analyzed.
PARTICIPANTS: Four thousand seven hundred ninety-one individuals in the 1994 survey.
MEASUREMENTS: BMI (kg/m
RESULTS: The relative risk of death as a function of BMI formed a nonsymmetric U-shaped pattern, with larger risks associated with lower BMI (<22.0) and minimal risks for BMI of 25.0 to 34.9. (BMI 22.0–24.9 was the reference.) Adjustments for demographic and health-related factors had little effect on this pattern. Nondisabled individuals exhibited a similar U-shaped pattern but with lower risks associated with lower BMI. For disabled individuals, the mortality–risk pattern was higher for lower BMI (<22.0) and flat for higher BMI, thus exhibiting an inverse J shape. BMI patterns were age sensitive, with disability status affecting sensitivity.
CONCLUSION: Overweight or mild (grade 1) obesity was not a risk factor for 9-year mortality in older Americans participating in the 1994 NLTCS. A flatter BMI pattern of the relative risk of death for disabled than for nondisabled individuals suggests that optimal body weight can be sensitive to age and health and well-being. 相似文献
The purpose of the study was to assess the feasibility and diagnostic performance of FDG-PET/MR imaging compared to PET/CT for staging of patients with a gynecological malignancy.
Methods25 patients with a gynecological malignancy were prospectively enrolled into this pilot study. Patients underwent sequential full-body PET/CT and PET/MR of the abdomen and pelvis after administration of a single dose of F-18 FDG. PET/MRI and PET/CT images were independently reviewed by two expert radiologists. Readers were blinded to the results of the other imaging procedures. Clinical and pathologic information was abstracted from medical charts.
Results18 patients were included in the final analysis with a median age of 62 years (range 31–88). 61% of patients (11/18) had cervical cancer, while the remaining patients had endometrial cancer. PET/MRI as compared to PET/CT detected all primary tumors, 7/7 patients with regional lymph nodes, and 1/1 patient with an abdominal metastasis. Two patients had additional lymph nodes outside of the abdominopelvic cavity detected on PET/CT that were not seen on PET/MRI, whereas 6 patients had parametrial invasion and one patient had invasion of the bladder seen on PET/MRI not detected on PET/CT. Five cervical cancer patients had discordant clinical vs. radiographic staging based on PET/MRI detection of soft tissue involvement. Management changed for two patients who had clinical stage IB1 and radiographic stage IIB cervical cancer.
ConclusionsPET/MRI is feasible and has at least comparable diagnostic ability to PET/CT for identification of primary cervical and endometrial tumors and regional metastases. PET/MRI may be superior to PET/CT for initial radiographic assessment of cervical cancers.
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