Economic evaluation of toric intraocular lens: a short- and long-term decision analytic model.

OBJECTIVE: To assess the economic value of improved uncorrected visual acuity among patients with cataract and preexisting astigmatism treated with toric intraocular lenses (IOLs) compared with conventional monofocal IOLs. METHODS: We developed a decision analytic model of hypothetical patients with preexisting astigmatism. We examined costs and outcomes among patients 65 years and older with cataract and preexisting astigmatism (1.5-3.0 diopters) who were receiving either toric or conventional IOLs with and without intraoperative refractive correction (IRC). Data were obtained from the literature and from a survey of 60 US ophthalmologists. Total medical costs of bilateral treatment were calculated for the first posttreatment year and remaining lifetime. Cost-effectiveness and cost-utility outcomes were computed. Future costs and utilities were discounted by 3%. RESULTS: A larger proportion of patients receiving toric IOLs achieved distance vision spectacle independence (67%) and uncorrected visual acuity of 20/25 or better OU (53%) compared with conventional IOLs with (63% and 48%, respectively) or without IRC (53% and 44%, respectively), resulting in fewer future vision corrections. Toric IOLs provided an additional 10.20 quality-adjusted life years (QALYs) compared with conventional IOLs with (10.14 QALYs) and without IRC (10.10 QALYs). Higher first-year costs of the toric IOL ($5739) compared with the conventional IOL with ($5635) or without ($4687) IRC were offset by lifetime cost savings of $34 per patient, $393 per patient achieving uncorrected visual acuity of 20/25 or better, and $349 per QALY compared with the conventional IOL without IRC. CONCLUSIONS: Toric IOLs reduce lifetime economic costs by reducing the need for glasses or contact lenses following cataract removal. These results can inform physicians and patients regarding the value of toric IOLs in the treatment of cataract and preexisting astigmatism.

Cost-effectiveness of amiodarone in cardiac surgery.

Atrial fibrillation is the most common complication after open-heart surgery. The incidence rate is 25-50%. This review summarizes findings of economic studies of amiodarone prophylaxis in cardiac surgery patients. Data were pooled from more than 15 studies. Four meta-analyses combining six to 19 amiodarone trials indicated a significant decrease in the incidence of postoperative atrial fibrillation (odds ratio range: 0.50-0.54). Other studies (individual randomized controlled trials, naturalistic studies and economic models) supported this finding. A majority of studies showed that amiodarone prophylaxis was cost neutral and resulted in a decrease in the length of stay, the main cost driver in postoperative atrial fibrillation. Selective use of amiodarone in high-risk patients (over 70 years, history of atrial fibrillation and chronic obstructive pulmonary disease, and concurrent valve surgery) will potentially enhance its cost-effectiveness.

Intestinal antiinflammatory effects of thiazolidenedione peroxisome proliferator-activated receptor-gamma ligands on T helper type 1 chemokine regulation include nontranscriptional control mechanisms.

Crohn's disease is associated with an excessive T helper (TH) type 1 inflammatory immune response. Reducing the influx of disease-associated CD4+ TH1 cells into the inflamed intestine is likely to be beneficial in preventing a disease flare-up and even possibly in reducing the effect of acute disease. Thiazolidenedione (TZD) ligands, which activate peroxisome proliferator-activated receptor-gamma (PPARgamma), have been shown to reduce TH1 inflammation in murine models of colitis, primarily in a preventative fashion. To determine whether PPARgamma ligands reduce this inflammation in part by reducing TH1 chemoattractant levels in vivo, the TZD pioglitazone was tested for its effects on a TH1 chemokine (CXCL10) in 2 models of colitis (i.e., dextran sodium sulfate and 2,4,6-dinitrobenzene sulfonic acid-mediated colitis). In both models, CXCL10 levels were significantly reduced by pioglitazone. Because TZDs can affect gene expression either directly, by regulating the binding of PPARgamma to consensus promoter elements, or indirectly, by modulating other signaling pathways that can affect gene transcription, the regulation of CXCL10 by TZDs was investigated in vitro in both HT-29 colon epithelial cells and THP-1 monocyte/macrophage cells. TZDs significantly reduced CXCL10 protein levels from activated HT-29 cells and THP-1-derived macrophages in a dose-dependent manner at nanomolar concentrations. However, TZDs did not affect messenger RNA levels or nuclear factor-kappaB activation at these concentrations in these cells. These findings imply the existence of a novel posttranscriptional regulatory antiinflammatory mechanism by TZDs that is not associated with reductions in nuclear factor-kappaB activation.

Inhibition kinetics of the gastric H,K-ATPase by K-competitive inhibitor SCH28080 as a tool for investigating the luminal ion pathway.

The gastric H,K-ATPase and the Na,K-ATPase both are stimulated by luminal K(+), but differ in sensitivity to K(+)-competitive inhibitors (ouabain and SCH28080), which implies a difference in structure near the luminal ion pathways in these two pumps. Knowledge of the amino acids in the H,K-ATPase that affect the mode of inhibition by SCH28080 and inhibitor affinity should provide insight into the regions of the membrane domain influencing the inhibitor selectivity and the luminal route to the ion transport site. Mutational scans in M4, 5, 6, and 8 have shown that amino acid residues affecting ion affinity (E343, K791, E795, E820, D824, E936) with either no or a lesser effect on the inhibitor affinity are located in the middle of the membrane domain. The residues significantly reducing inhibitor affinity, but not ion affinity (L809, P810, L811, T813, I816, Y925, T929), are located in the exoplasmic 5-6 loop and the luminal ends of M6 and M8. This suggests that the binding domain for SCH28080 contains the surface between L809 in the 5-6 loop and C813 at the luminal end of M6, approximately two helical turns out from the ion binding region, where it blocks an ion access pathway. The mutations that change inhibitor kinetics are on the opposing faces of M6 and M8 and apparently modify the normal ion pathway or, perhaps, create an alternate ion pathway.