Background: Asthma can be difficult to diagnose, but bronchial provocation with methacholine, exercise or mannitol is helpful when used to identify bronchial hyperresponsiveness (BHR), a key feature of the disease. The utility of these tests in subjects with signs and symptoms of asthma but without a clear diagnosis has not been investigated. We investigated the sensitivity and specificity of mannitol to identify exercise-induced bronchoconstriction (EIB) as a manifestation of BHR; compared this with methacholine; and compared the sensitivity and specificity of mannitol and methacholine for a clinician diagnosis of asthma.

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OBJECTIVE:To compare longitudinal changes in weight, body fat, and ratio of central to peripheral fat mass among first-time depot-medroxyprogesterone acetate (DMPA) users to women using no hormonal contraception, and to evaluate user characteristics associated with that change. DESIGN: Prospective longitudinal study. SUBJECTS: Healthy women, aged 18-35 y, using DMPA for contraception (n ¼ 178) and women using no hormonal contraception (n ¼ 145). MEASUREMENTS: Weight, body fat, and the central distribution of fat, measured at 3-month intervals for 30 months, by electronic scale and dual-energy X-ray absorptiometry (DEXA). The ratio of central to peripheral distribution of body fat was computed by dividing the body fat in the conventional DEXA trunk region of interest (ROI) by the ROI's that encompass the arms, hips and legs. RESULTS: Women using DMPA had a significantly greater increase in all measures of fatness than women using no hormonal method of contraception (Po0. In contrast, weight, fat mass and the ratio of central to peripheral fat mass of control participants remained virtually unchanged over the same time period. Women with higher baseline physical activity levels had a smaller increase in body fat (P ¼ 0.003) and the fat ratio (P ¼ 0.03), but not weight (P ¼ 0.48). No other user characteristics including, smoking, past oral contraceptive use or previous pregnancies predicted change in level of fatness. CONCLUSIONS: This study has demonstrated a change in body composition toward greater fatness and toward a central redistribution of fat among DMPA users as compared to controls and provides important information to be used when counseling women regarding contraceptive methods. Given the potential long-term implication of these changes, further study is recommended to determine whether the gains in fatness are reversed following DMPA discontinuation and to examine the role of progestins in the development and maintenance of obesity.

BackgroundExercise testing to aid diagnosis of exercise-induced bronchoconstriction (EIB) is commonly performed. Reproducibility of the airway response to a standardized exercise protocol has not been reported in subjects being evaluated with mild symptoms suggestive of asthma but without a definite diagnosis. This study examined reproducibility of % fall in FEV1 and area under the FEV1 time curve for 30 minutes in response to two exercise tests performed with the same intensity and duration of exercise, and inspired air conditions.MethodsSubjects with mild symptoms of asthma exercised twice within approximately 4 days by running for 8 minutes on a motorized treadmill breathing dry air at an intensity to induce a heart rate between 80-90% predicted maximum; reproducibility of the airway response was expressed as the 95% probability interval.ResultsOf 373 subjects challenged twice 161 were positive (≥10% fall FEV1 on at least one challenge). The EIB was mild and 77% of subjects had <15% fall on both challenges. Agreement between results was 76.1% with 56.8% (212) negative (< 10% fall FEV1) and 19.3% (72) positive on both challenges. The remaining 23.9% of subjects had only one positive test. The 95% probability interval for reproducibility of the % fall in FEV1 and AUC0-30 min was ± 9.7% and ± 251% for all 278 adults and ± 13.4% and ± 279% for all 95 children. The 95% probability interval for reproducibility of % fall in FEV1 and AUC0-30 min for the 72 subjects with two tests ≥10% fall FEV1 was ± 14.6% and ± 373% and for the 34 subjects with two tests ≥15% fall FEV1 it was ± 12.2% and ± 411%. Heart rate and estimated ventilation achieved were not significantly different either on the two test days or when one test result was positive and one was negative.ConclusionsUnder standardized, well controlled conditions for exercise challenge, the majority of subjects with mild symptoms of asthma demonstrated agreement in test results. Performing two tests may need to be considered when using exercise to exclude or diagnose EIB, when prescribing prophylactic treatment to prevent EIB and when designing protocols for clinical trials.

Women are at higher risk for osteoporosis, but most of the literature examining the effect of alcohol abuse on bone mineral density (BMD) has been in men. The aim of this study was to determine differences in BMD and fracture prevalence among women in treatment for alcohol abuse, in recovery and non-alcohol-dependent women. This cross-sectional study was completed at two residential substance abuse centers in Iowa (USA). The patients were Caucasian women, aged 18-70 years, in treatment for alcohol abuse and dependence ( n=228); in recovery and abstaining from alcohol ( n=156); and women with no history of alcohol abuse ( n=447). The main outcome measures were femoral neck and lumbar spine BMD measured by dual-energy X-ray absorptiometry (DXA); self-reported lifetime fracture prevalence. After adjusting for age and menopausal status, women in treatment had BMDs that were 7.7% ( p<0.01) and 6.3% ( p<0.01) lower at the femoral neck and lumbar spine, respectively, than non-alcohol-abusing women, and 4.8% lower at both bone sites ( p<0.01) than women in recovery. Femoral neck BMD of women in recovery was 3.1% lower ( p<0.01) than in non-alcohol-dependent women; however, the difference was not significant following multivariate analysis. Women in treatment and recovery reported more fractures during childhood and early adolescence than non-alcohol-dependent women ( p<0.01). Women in recovery also reported significantly greater numbers of fractures following sobriety than their paired non-alcohol-dependent counterparts. Alcohol abuse and dependence was associated with lower femoral neck and lumbar spine BMD. Women with histories of alcohol dependence had a higher lifetime prevalence of fractures, including time periods before the onset of problem drinking and following abstinence, suggesting that factors other than acute intoxication contributed to the greater fracture prevalence.