Changes in bone mineral density over time by body mass index in the health ABC study.

UNLABELLED: Obesity appears protective against osteoporosis in cross-sectional studies. However, results from this longitudinal study found that obesity was associated with bone loss over time. Findings underscore the importance of looking at the longitudinal relationship, particularly given the increasing prevalence and duration of obesity among older adults. INTRODUCTION: Cross-sectional studies have found a positive association between body mass index (BMI) and bone mineral density (BMD), but little is known about the longitudinal relationship in US older adults. METHODS: We examined average annual rate of change in BMD by baseline BMI in the Health, Aging, and Body Composition Study. Repeated measurement of BMD was performed with dual-energy X-ray absorptiometry (DXA) at baseline and years 3, 5, 6, 8, and 10. Multivariate generalized estimating equations were used to predict mean BMD (femoral neck, total hip, and whole body) by baseline BMI (excluding underweight), adjusting for covariates. RESULTS: In the sample (n = 2570), 43 % were overweight and 24 % were obese with a mean baseline femoral neck BMD of 0.743 g/cm(2), hip BMD of 0.888 g/cm(2), and whole-body BMD of 1.09 g/cm(2). Change in total hip or whole-body BMD over time did not vary by BMI groups. However, obese older adults lost 0.003 g/cm(2) of femoral neck BMD per year more compared with normal weight older adults (p < 0.001). Femoral neck BMD change over time did not differ between the overweight and normal weight BMI groups (p = 0.74). In year 10, adjusted femoral neck BMD ranged from 0.696 g/cm(2) among obese, 0.709 g/cm(2) among normal weight, and 0.719 g/cm(2) among overweight older adults. CONCLUSIONS: Findings underscore the importance of looking at the longitudinal relationship between body composition and bone mineral density among older adults, indicating that high body mass may not be protective for bone loss over time.

The association between body mass index, weight loss and physical function in the year following a hip fracture.

OBJECTIVES: To determine whether body mass index (BMI) at the time of hospitalization or weight change in the period immediately following hospitalization predict physical function in the year after hip fracture. DESIGN: Prospective observational study. SETTING: Two hospitals in Baltimore, Maryland. PARTICIPANTS: Female hip fracture patients age 65 years or older (N=136 for BMI analysis, N=41 for analysis of weight change). MEASUREMENTS: Body mass index was calculated based on weight and height from the medical chart. Weight change was based on DXA scans at 3 and 10 days post fracture. Physical function was assessed at 2, 6 and 12 months following fracture using the lower extremity gain scale (LEGS), walking speed and grip strength. RESULTS: LEGS score and walking speed did not differ across BMI tertiles. However, grip strength differed significantly across BMI tertiles (p=0.029), with underweight women having lower grip strength than normal weight women at all time points. Women experiencing the most weight loss (>4.8%) had significantly lower LEGS scores at all time points, slower walking speed at 6 months, and weaker grip strength at 12 months post-fracture relative to women with more modest weight loss. In adjusted models, overall differences in function and functional change across all time points were not significant. However, at 12 months post fracture,women with the most weight loss had an average grip strength 7.0 kg lower than women with modest weight loss (p=0.030). CONCLUSIONS: Adjustment for confounders accounts for much of the relationships between BMI and function and weight change and function in the year after fracture. However, weight loss is associated with weakness during hip fracture recovery. Weight loss during and immediately after hospitalization appears to identify women at risk of poor function and may represent an important target for future interventions.

Effect on time in quarantine of the choice of program for eradication of footrot from 196 sheep flocks in southern New South Wales.

OBJECTIVE: To identify and compare programs for eradicating virulent footrot (VFR) chosen by owners of quarantined sheep flocks in southern New South Wales. METHOD: Data from 196 sheep flocks in the Wagga Wagga and Young Rural Lands Protection Boards were used to determine the program chosen, the influence of flock size on the program chosen and the effects of the program chosen and the use of contractors on the time in quarantine. RESULTS: The most popular programs in flocks using a single program were: total destocking (61/173; 35.3%) and inspection and culling of affected animals (71/173; 41.0%). Treatment of known infected animals was chosen in 41 flocks and of those, 10 (5.8%) used antibiotics for treatment and 31 (17.9%) used foot-bathing. Combined programs were used in 23 flocks and in 10 flocks a change of program occurred before eradication was achieved. The choice of program was, to some extent, affected by flock size, with owners of small flocks (<500 sheep) more likely to destock. The chosen program strongly influenced the time in quarantine, the shortest time being for destocking (mean 284 days), followed by culling of infected sheep (395 days), treatment with antibiotics (433 days) and finally foot-bathing (502 days). Time in quarantine was significantly shorter when contractors were used. CONCLUSION: All the options chosen led to the eradication of VFR. However, in this sample both the choice of program and the use of contractors influenced the time taken to achieve eradication and therefore the time in quarantine. Based on time in quarantine, foot-bathing was the least desirable option for the eradication of VFR because of the significantly greater time involved, perpetuation of risk to neighbours and increased cost of inspections. These findings were derived from flocks that were quarantined, but they are relevant to all flock owners considering eradication of VFR.

The effect of obesity combined with low muscle strength on decline in mobility in older persons: results from the InCHIANTI study.

OBJECTIVE: Both obesity and muscle impairment are increasingly prevalent among older persons and negatively affect health and physical functioning. However, the combined effect of coexisting obesity and muscle impairment on physical function decline has been little studied. We examined whether obese persons with low muscle strength experience significantly greater declines in walking speed and mobility than persons with only obesity or low muscle strength. DESIGN: Community-dwelling adults aged > or = 65 years (n = 930) living in the Chianti geographic area (Tuscany, Italy) were followed for 6 years in the population-based InCHIANTI study. MEASUREMENTS: On the basis of baseline measurements (1998-2000), obesity was defined as body mass index (BMI) > or = 30 kg/m(2) and low muscle strength as lowest sex-specific tertile of knee extensor strength. Walking speed and self-reported mobility disability (ability to walk 400 m or climb one flight of stairs) were assessed at baseline and at 3- and 6-year follow-up. RESULTS: At baseline, obese persons with low muscle strength had significantly lower walking speed compared with all other groups (P < or = 0.05). In longitudinal analyses, obese participants with low muscle strength had steeper decline in walking speed and high risk of developing new mobility disability over the 6-year follow-up compared with those without obesity or low muscle strength. After the age of 80, the differences between groups were substantially attenuated. The differences seen in walking speed across combination of low muscle strength and obesity groups were partly explained by 6-year changes in muscle strength, BMI and waist circumference. CONCLUSIONS: Obesity combined with low muscle strength increases the risk of decline in walking speed and developing mobility disability, especially among persons < 80 years old.

Socioeconomic disparities in the seroprevalence of cytomegalovirus infection in the US population: NHANES III.

There is a strong relationship between socioeconomic status (SES) and health outcomes in the United States, although the mechanisms are poorly understood. Increasing evidence points to links between lifelong exposure to infectious disease and subsequent chronic disease. Exposure and susceptibility to infections may be one way SES affects long-term health, although little population-based research to date has examined social patterning of infections in the United States. This paper tests the relationship between income, education, race/ethnicity and seroprevalence of cytomegalovirus (CMV) infection at different ages in a representative sample of the US population, and tests potential mediators for these relationships. The study finds significant racial and socioeconomic disparities in CMV seroprevalence beginning at early ages and persisting into middle age. Potential exposures do not explain the relationship between SES and CMV positivity. Because reactivation of latent CMV infections may contribute to chronic disease and immune decline later in life, future research should determine the exposure or susceptibility pathways responsible for these disparities in the prevalence of CMV infection.

Efficacy of a novel copper-based footbath preparation for the treatment of ovine footrot during the spread period.

OBJECTIVE: To determine the efficacy of a novel copper based footbath preparation (CHF-1020) for treatment of ovine footrot during the spread period. DESIGN: A series of field trials with treated and control groups run together. ANIMALS: Mobs of at least 125 sheep on each of six properties in southern New South Wales with equal numbers of controls. PROCEDURE: Sheep of group A were treated after minimal paring by making them stand in CHF-1020 for 15 minutes. Treatment was undertaken at intervals throughout the period of the trials (14 September to 17 December 1993). Group A sheep were run on the same pasture as those from group B (untreated sheep). RESULTS: The percentage of sheep exhibiting clinical signs of ovine footrot at the start of the trial ranged from 35 to 88% at score 3 or higher, using a 0 to 5 footscoring system. During the trial, the percentage of infected sheep (greater or equal to score 2) in group B increased and ranged from 40 to 90%. The level of infected sheep in group A on each property was reduced progressively to 1 to 16%. Cure rates of 45 to 94% were achieved, with the lowest rate being on a property with a metal footbath. The next lowest cure rate was 73%. Results indicated that treatment should be undertaken at 2-weekly intervals while spread continues. Treated sheep can be returned to contaminated pastures. CONCLUSION: CHF-1020 is effective during the spread period and can be used for the progressive eradication of ovine footrot.

Prenatal sonographic findings in trisomy 13, 18, 21 and 22. A review of 46 cases.

A study of 46 patients with trisomic fetuses was performed to determine if there are one or more second-trimester ultrasonic findings predictive of aneuploidy. Videotapes of ultrasonography performed prior to amniocentesis on the 46 fetuses with autosomal trisomy and from a control group of 50 chromosomally normal fetuses were reviewed without knowledge of the karyotype. Fetuses with autosomal trisomies had short long bones, especially femurs, as well as high biparietal diameter/femur length ratios. In addition, a nuchal thickness of > 5 mm, abnormal heart anatomy, slight pyelectasis, increased bowel echogenicity and/or abnormal flexion of the hands were all predictive of autosomal trisomies.

Antenatal classification of hydrops fetalis.

Among 12,572 pregnant women referred for ultrasound examination from 1985-1990, 76 fetuses had ultrasonographic findings of hydrops fetalis, ten immune and 66 nonimmune. Fetuses with cystic hygroma (20), heart defects or arrhythmias (13), or other congenital anomalies (15) accounted for the majority of the nonimmune cases. Antenatal chromosomal studies were available in 42 fetuses with nonimmune hydrops, of which 14 (34%) were abnormal with seven monosomes and six trisomies. Seventeen cases of hydrops (22%) were classified as idiopathic because they had no recognizable etiology. It is concluded that: 1) The ultrasonographic incidence of fetal hydrops in referral centers can be as high as one in 165 pregnancies; 2) most cases of fetal hydrops are of the nonimmune type, which can occur in a low-risk population and can be detected with early second-trimester ultrasound screening; and 3) the complexity of this condition and the high rate of chromosomal abnormalities require referral to a high-risk center for evaluation and pregnancy management.