The relationship between body mass index and quality of life in community-living older adults living in the United States.

BACKGROUND: Carrying excess weight is associated with various chronic conditions especially in older adults, and can have a negative influence on the quality of life of this population. OBJECTIVE: The objective of this study was to estimate the independent (i.e. adjusted for demographic, socioeconomic and health status differences) impact of Body Mass Index (BMI) on health-related quality of life. DESIGN: A mail survey was sent to 60,000 older adults living in 10 states. METHODS: The survey assessed quality of life using the average physical component scores (PCS) and mental component scores (MCS) obtained from the Veterans Rand 12-item (VR-12) health status tool embedded in the survey. Ordinary least squares (OLS) regression techniques were used to estimate the independent impact of each BMI category on quality of life, compared to the impact of other chronic conditions. RESULTS: A total of 22,827 (38%) eligible sample members responded to the survey. Of those, 2.2% were underweight, 38.5% had a normal BMI, 37.0% were overweight, 18.5% were obese and 1.9% were morbidly obese. Following OLS regression techniques, respondents' PCS values were statistically significantly lower for the underweight, overweight, obese and morbidly obese BMI categories, compared to the normal BMI group. Compared with all other chronic conditions, being morbidly obese (-6.0 points) had the largest negative impact on the PCS. Underweight was the only BMI category with a statistically significantly lower MCS value. CONCLUSIONS: The greatest negative impacts of the various BMI categories on quality of life were on physical rather than mental aspects, especially for those in the underweight, obese and morbidly obese categories, more so than many other chronic conditions.

Effects of retinoic acid on airspace development and lung collagen in hyperoxia-exposed newborn rats.

Impaired septal formation and decreased alveolarization are often caused by hyperoxic injury to the developing lung and are characteristic features of bronchopulmonary dysplasia. Dexamethasone, frequently administered to infants during oxygen exposure, also inhibits septal formation in the newborn lung. Vitamin A administration reduces the incidence of bronchopulmonary dysplasia in vitamin A-deficient premature infants, and retinoic acid improves alveolarization in newborn rats treated with dexamethasone, indicating that retinoic acid may be useful in preventing hyperoxia-induced impaired septation in bronchopulmonary dysplasia. To investigate whether treatment with retinoic acid during exposure to hyperoxia would improve septal formation, newborn rats exposed to > or =90% O(2) from d 3 of life to d 14 were treated with retinoic acid (d 3-13 of life) and/or dexamethasone (d 4-13 of life). In contrast with the effects of retinoic acid on dexamethasone-induced inhibition of alveolarization, we found that retinoic acid did not improve septal formation or decrease airspace size in animals exposed to hyperoxia alone or to hyperoxia plus dexamethasone. Retinoic acid did, however, increase collagen in airspace walls as demonstrated by staining and immunohistochemistry. There was no increase in procollagen mRNA by Northern hybridization analysis, indicating that retinoic acid-associated increases in lung collagen are likely due to posttranscriptional regulation. There was a trend toward increased survival in hyperoxia in animals treated with retinoic acid to the extent that combined therapy with retinoic acid and dexamethasone resulted in the greatest improvement in animal survival. These results suggest that although retinoic acid may be of benefit in hyperoxia-induced lung injury and may have important effects on lung matrix, it does not prevent impairment of septation or induce alveolar formation during exposure to hyperoxia.