Body composition during childhood and adolescence: relations to bone strength and microstructure.

CONTEXT: Numerous studies have examined the association of body composition with bone development in children and adolescents, but none have used micro-finite element (µFE) analysis of high-resolution peripheral quantitative computed tomography images to assess bone strength. OBJECTIVE: This study sought to examine the relations of appendicular lean mass (ALM) and total body fat mass (TBFM) to bone strength (failure load) at the distal radius and tibia. DESIGN, PARTICIPANTS, AND SETTING: This was a cross-sectional study of 198 healthy 8- to <15-year-old boys (n = 109) and girls (n = 89) performed in a Clinical Research Unit. RESULTS: After adjusting for bone age, height, fracture history, ALM, and TBFM, multiple linear regression analyses in boys and girls, separately, showed robust positive associations between ALM and failure loads at both the distal radius (boys: ß = 0.92, P < .001; girls: ß = 0.66, P = .001) and tibia (boys: ß = 0.96, P < .001; girls: ß = 0.66, P < .001). By contrast, in both boys and girls the relationship between TBFM and failure load at the distal radius was virtually nonexistent (boys: ß = -0.07; P = .284; girls: ß = -0.03; P = .729). At the distal tibia, positive, albeit weak, associations were observed between TBFM and failure load in both boys (ß = 0.09, P = .075) and girls (ß = 0.17, P = .033). CONCLUSIONS: Our data highlight the importance of lean mass for optimizing bone strength during growth, and suggest that fat mass may have differential relations to bone strength at weight-bearing vs non-weight-bearing sites in children and adolescents. These observations suggest that the strength of the distal radius does not commensurately increase with excess gains in adiposity during growth, which may result in a mismatch between bone strength and the load experienced by the distal forearm during a fall. These findings may explain, in part, why obese children are over-represented among distal forearm fracture cases.

Semi-automated vectorial analysis of anorectal motion by magnetic resonance defecography in healthy subjects and fecal incontinence.

BACKGROUND: Inter-observer variability limits the reproducibility of pelvic floor motion measured by magnetic resonance imaging (MRI). Our aim was to develop a semi-automated program measuring pelvic floor motion in a reproducible and refined manner. METHODS: Pelvic floor anatomy and motion during voluntary contraction (squeeze) and rectal evacuation were assessed by MRI in 64 women with fecal incontinence (FI) and 64 age-matched controls. A radiologist measured anorectal angles and anorectal junction motion. A semi-automated program did the same and also dissected anorectal motion into perpendicular vectors representing the puborectalis and other pelvic floor muscles, assessed the pubococcygeal angle, and evaluated pelvic rotation. KEY RESULTS: Manual and semi-automated measurements of anorectal junction motion (r = 0.70; P < 0.0001) during squeeze and evacuation were correlated, as were anorectal angles at rest, squeeze, and evacuation; angle change during squeeze or evacuation was less so. Semi-automated measurements of anorectal and pelvic bony motion were also reproducible within subjects. During squeeze, puborectalis injury was associated (P ≤ 0.01) with smaller puborectalis but not pelvic floor motion vectors, reflecting impaired puborectalis function. The pubococcygeal angle, reflecting posterior pelvic floor motion, was smaller during squeeze and larger during evacuation. However, pubococcygeal angles and pelvic rotation during squeeze and evacuation did not differ significantly between FI and controls. CONCLUSION & INFERENCES: This semi-automated program provides a reproducible, efficient, and refined analysis of pelvic floor motion by MRI. Puborectalis injury is independently associated with impaired motion of puborectalis, not other pelvic floor muscles in controls and women with FI.

The changing incidence of oesophageal and gastric adenocarcinoma by anatomic sub-site.

BACKGROUND: The incidence rates of gastric and oesophageal adenocarcinoma are changing significantly, but little is known about specific sub-sites. AIM: To use a population-based approach to describe the trends in the site-specific incidence of oesophageal and gastric adenocarcinoma. METHODS: Using the Rochester Epidemiology Project, all cases of gastric and oesophageal adenocarcinoma among Olmsted County, Minnesota, residents first diagnosed between 1971 and 2000 were identified (n = 186). Complete in-patient and out-patient records were reviewed and site determined from pathological, surgical, endoscopic and radiological reports. RESULTS: Between the decades of 1971-1980 and 1991-2000, the incidence of oesophageal adenocarcinoma increased significantly from 0.4 to 2.5 per 100 000 person-years. The incidence of adenocarcinoma of the oesophagogastric junction also increased from a rate of 0.6 to 2.2 per 100 000 person-years. The incidence rate of cancer involving the gastric cardia was stable but the incidence of adenocarcinoma involving distal gastric sites declined. Combined oesophageal and oesophagogastric junction adenocarcinoma (4.7 per 1 000 000 person-years) was as common as gastric adenocarcinoma (3.4 per 100 000 person-years) in 1991-2000. CONCLUSIONS: The incidence rates of adenocarcinoma involving proximal gastric sub-sites do not appear to be increasing in a manner similar to those involving oesophageal sub-sites.

Relationship of tobacco use to depressive disorders and suicidality among patients treated for alcohol dependence.

This population-based, retrospective cohort study examined the association of tobacco use and diagnosis of a depressive disorder (DD) and suicide attempts (SA) before and after discharge from an inpatient addiction program (IAP). All 813 Olmsted County, Minnesota residents (537 males, 276 females) admitted for the first time to the IAP for treatment of alcoholism during the period 1972-1983 were studied. Tobacco use status at admission was classified as ever (current or former use) (85.5%), never (8.6%), or missing (5.9%). Subjects were followed through 1994. Current or former use of tobacco was markedly lower among those with a prior diagnosis of DD than those without this diagnosis (73.6% vs. 89.3%, p<0.001). Although females were more likely to have a diagnosis of DD and were less likely to have ever used tobacco than males, gender did not explain the relationship between tobacco use and DD. Tobacco use status was unrelated to a DD diagnosis after discharge from the IAP and was not associated with SA.

Impact of case ascertainment on recent trends in diabetes incidence in Rochester, Minnesota.

The authors previously reported an increase in the incidence of diabetes mellitus among Rochester, Minnesota, residents during the period 1970-1989. This study provides updated rates from data collected through 1994. Trends in diabetes surveillance, i.e., the proportion of residents who had a blood glucose measurement in each year between 1987 and 1994, are also provided. The authors reviewed medical records to identify residents aged 30 years or more who first met National Diabetes Data Group criteria for diabetes between January 1, 1970, and December 31, 1994. Age- and sex-adjusted incidence rates were calculated for successive quinquennia (5-year periods), and Poisson regression was used to test for an effect of calendar year; calendar period (1970-1989 vs. 1990-1994) was added to assess whether the association with calendar year varied in the most recent quinquennium. Altogether, 1,992 Rochester residents first met National Diabetes Data Group criteria for diabetes between 1970 and 1994. The age-adjusted incidence per 100,000 person-years increased 67% for males (267.0 vs. 444.8) and 42% for females (225.4 vs. 319.1) between 1970-1974 and 1990-1994. Calendar year (p < 0.001) and calendar period (p = 0.026) were significant, suggesting that rates accelerated during 1990-1994. The proportion of residents with at least one blood glucose measurement per year was unchanged (p = 0.181) from 1987 to 1994, while the incidence of diabetes increased (p = 0.033). Thus, the authors conclude that the increase in diabetes incidence accelerated over the last quinquennium and was not due to increased surveillance.