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Background: Non-specific bronchial hyperresponsiveness (NSBH) is a known predictor of accelerated rate of decline in lung function in smokers. Polymorphisms of the beta(2) adrenergic receptor (ADRB2) have previously been associated with NSBH and bronchodilator response (BDR) in asthmatics. Based on these associations, we hypothesised that ADRB2 polymorphisms would be associated with NSBH and BDR as well as an accelerated rate of decline in lung function among smokers.Methods: The prevalence of two ADRB2 polymorphisms, Arg16-->Gly and Gln27-->Glu, was examined in 587 smokers chosen from the NHLBI Lung Health Study for having the fastest (n=282) and slowest (n=305) 5 year rate of decline in forced expiratory volume in 1 second (FEV(1); mean DeltaFEV(1) -4.14 and +1.08% predicted/year, respectively).Results: Contrary to our hypothesis, no ADRB2 allele or haplotype was associated with NSBH, BDR, or rate of decline in lung function. However, there was a significant negative association between heterozygosity at position 27 and a fast decline in lung function (adjusted odds ratio 0.56, 95% CI 0.40 to 0.78, p=0.0007).Conclusions: Heterozygosity at position 27 may be protective against an accelerated rate of decline in lung function. The polymorphism at position 16 does not contribute to the rate of decline in lung function, measures of NSBH, or BDR in smokers. [ABSTRACT FROM AUTHOR]

The article presents a study on the effectiveness of simvastatin in preventing exacerbations in a large, multicenter, randomized trial, Topics discussed include patients excluded in the study, a comparison of the low-density lipoprotein cholesterol levels in the simvastatin-treated patients and those who received placebo, and the number of nonfatal serious adverse events per person-year.

We extend Wei and Tanner's (1991) multiple imputation approach in semi-parametric linear regression for univariate censored data to clustered censored data. The main idea is to iterate the following two steps: 1) using the data augmentation to impute for censored failure times; 2) fitting a linear model with imputed complete data, which takes into consideration of clustering among failure times. In particular, we propose using the generalized estimating equations (GEE) or a linear mixed-effects model to implement the second step. Through simulation studies our proposal compares favorably to the independence approach (Lee et al., 1993), which ignores the within-cluster correlation in estimating the regression coefficient. Our proposal is easy to implement by using existing softwares. [ABSTRACT FROM AUTHOR]

Objective: To determine whether a program incorporating smoking intervention and use of an inhaled bronchodilator can slow the rate of decline in forced expiratory volume in 1 second (FEV1) in smokers aged 35 to 60 years who have mild obstructive pulmonary disease.Design: Randomized clinical trial. Participants randomized with equal probability to one of the following groups: (1) smoking intervention plus bronchodilator, (2) smoking intervention plus placebo, or (3) no intervention.Setting: Ten clinical centers in the United States and Canada.Participants: A total of 5887 male and female smokers, aged 35 to 60 years, with spirometric signs of early chronic obstructive pulmonary disease.Interventions: Smoking intervention: intensive 12-session smoking cessation program combining behavior modification and use of nicotine gum, with continuing 5-year maintenance program to minimize relapse. Bronchodilator: ipratropium bromide prescribed three times daily (two puffs per time) from a metered-dose inhaler.Main Outcome Measures: Rate of change and cumulative change in FEV1 over a 5-year period.Results: Participants in the two smoking intervention groups showed significantly smaller declines in FEV1 than did those in the control group. Most of this difference occurred during the first year following entry into the study and was attributable to smoking cessation, with those who achieved sustained smoking cessation experiencing the largest benefit. The small noncumulative benefit associated with use of the active bronchodilator vanished after the bronchodilator was discontinued at the end of the study.Conclusions: An aggressive smoking intervention program significantly reduces the age-related decline in FEV1 in middle-aged smokers with mild airways obstruction. Use of an inhaled anticholinergic bronchodilator results in a relatively small improvement in FEV1 that appears to be reversed after the drug is discontinued. Use of the bronchodilator did not influence the long-term decline of FEV1. [ABSTRACT FROM AUTHOR]

Objective: To determine whether optimized glycemic control in type I diabetic recipients of renal allografts will prevent or delay diabetic renal lesions in the allograft.Design: Prospective, controlled, and randomized trial of glycemic control in an inception cohort of type I diabetic renal allograft recipients. The experimental group underwent maximized glycemic control, and the standard group was treated in the same way as other patients in the transplant clinic. Patients underwent baseline (before transplant) and 5-year posttransplant allograft biopsies.Setting: University of Minnesota Hospital and Clinic and the Clinical Research Center and Hennepin County Medical Center, Minneapolis.Patients: Type I diabetics with terminal diabetic renal failure undergoing renal transplantation. Forty-eight patients randomized to maximized or standard control completed the trial.Intervention: Subcutaneous insulin given several times a day or continuously (maximized group) and once or twice each day (standard group) was used throughout the trial. A significant difference for hemoglobin A1 level was maintained (mean +/- SD: standard, 0.117 +/- 0.013; maximized, 0.096 +/- 0.016; P < 0.001).Main Outcome: The primary end point of this trial was the difference between the groups in renal glomerular mesangial expansion as determined by electron microscopy.Results: There was a more than twofold increase in the volume fraction of mesangial matrix per glomerulus in the standard group (mean +/- SD, 0.043 +/- 0.034) compared with the maximized group (0.019 +/- 0.038; P = .024). The threefold increase in arteriolar hyalinosis, the greater widening of the glomerular basement membrane, and increase of volume fraction of the total mesangium in the patients who received standard treatment all approached significance (P = .10 or less). The incidence of severe hypoglycemic episodes was greater in the maximized group (1.7 per patient per year) than in the standard treatment group (< 0.1 per patient per year; P < .001).Conclusions: This trial indicates a causal relationship between hyperglycemia and an important lesion of diabetic nephropathy, mesangial matrix expansion, in renal allografts transplanted into diabetic recipients. In addition, the results with other lesions central to the development of diabetic nephropathy support the major conclusion. [ABSTRACT FROM AUTHOR]