Objective To assess risks of mortality associated with use of individual antipsychotic drugs in elderly residents in nursing homes.Design Population based cohort study with linked data from Medicaid, Medicare, the Minimum Data Set, the National Death Index, and a national assessment of nursing home quality. Setting Nursing homes in the United States.Participants 75 445 new users of antipsychotic drugs (haloperidol, aripiprazole, olanzapine, quetiapine, risperidone, ziprasidone). All participants were aged ≥65, were eligible for Medicaid, and lived in a nursing home in 2001-5. Main outcome measuresCox proportional hazards models were used to compare 180 day risks of all cause and cause specific mortality by individual drug, with propensity score adjustment to control for potential confounders.Results Compared with risperidone, users of haloperidol had an increased risk of mortality (hazard ratio 2.07, 95% confidence interval 1.89 to 2.26) and users of quetiapine a decreased risk (0.81, 0.75 to 0.88). The effects were strongest shortly after the start of treatment, remained after adjustment for dose, and were seen for all causes of death examined. No clinically meaningful differences were observed for the other drugs. There was no evidence that the effect measure modification in those with dementia or behavioural disturbances. There was a dose-response relation for all drugs except quetiapine.Conclusions Though these findings cannot prove causality, and we cannot rule out the possibility of residual confounding, they provide more evidence of the risk of using these drugs in older patients, reinforcing the concept that they should not be used in the absence of clear need. The data suggest that the risk of mortality with these drugs is generally increased with higher doses and seems to be highest for haloperidol and least for quetiapine. IntroductionUp to a third of all elderly patients in nursing homes are treated with antipsychotic drugs. [1][2][3][4][5] In the past, inappropriate prescribing of antipsychotics in nursing homes has primarily been considered a marker of suboptimal care.6 7 Federal action thus focused primarily on defining and enforcing specific diagnostic criteria for the initiation and monitoring of these drugs (Omnibus Budget Reconciliation Act). 8 In recent years, evidence has accumulated that their use is a drug safety issue as well. After earlier warnings of increased risks of cerebrovascular events (with risperidone, olanzapine, and aripiprazole), 9 the Food and Drug Administration issued an advisory warning in 2005 that atypical antipsychotics were associated with a 60-70% increased risk of death compared with placebo in randomised controlled trials among older patients with dementia, and black box warnings were added to the labels of all atypical drugs. 10 Subsequent studies found risks at least as high among users of conventional antipsychotics, [11][12][13] RESEARCHpeople with dementia, the perceived need for some type of intervention in patients with severe persistent symptoms, ...
Bladder outlet obstruction secondary to benign prostatic hyperplasia induces numerous changes in bladder morphology, physiology, and pharmacology. These changes have been studied experimentally in various animal models, and while each species has advantages and disadvantages, it is unclear which is most like man. It has been shown that tissue hypertrophy leading to an increase in tissue mass develops rapidly after bladder outlet obstruction. Ischemia induced by the obstruction results in acute muscle dysfunction. The degree of functional impairment is directly related to the degree of tissue hypertrophy. However, the bladder contractile apparatus appears to have a surprising regenerative ability, such that recovery of bladder function becomes obvious 14 days after obstruction. Urody‐namic changes include an increase in urinary frequency and voiding pressure and a decrease in voided volume. Clinically, involuntary bladder contractions are often present. Determination of which of these specific aspects of outlet obstruction the investigator is interested in studying will dictate the selection of the most appropriate animal model.
Rapid structural and functional alterations have been noted in several models of partial outlet obstruction. To better characterize the rapid progression of alterations, the partially obstructed urinary bladders of mature NZW male rabbits were studied at 1, 3, 5, 7 and 14 days of outlet obstruction with respect to muscarinic receptor density, DNA, RNA, lipid and hydroxyproline content. Functional characteristics were assessed by measuring the in vitro response of the whole bladder to cholinergic and field stimulation. Wet weight increased eight-fold by day 7, decreasing to four-fold at day 14. Receptor density decreased by 50% by day 1 and remained low throughout. Although DNA concentration varied only slightly from controls, RNA increased four-fold by day 7. Hydroxyproline concentration per mg. tissue decreased in the obstructed bladder, yet total hydroxyproline content of the obstructed bladder significantly increased. Total lipids increased significantly during day 3 through 7 and decreased by day 14. Cystometry revealed a large capacity low pressure system at day 1 which rapidly changed to a low compliance system of lesser volume by day 14. Bladder emptying was significantly impaired in all obstructed specimens. Additionally, electrical field stimulation was significantly less effective than cholinergic stimulation in effecting bladder emptying. The above findings suggest that rapid changes in biochemical parameters occur during the early stage of acute obstruction which may in part be secondary to metabolic or inflammatory alterations in the detrusor. It additionally suggests that the myogenic alterations in partial outlet obstruction are rapid and partially adaptive, while neurogenic alterations appear degenerative and display a lesser degree of short term adaptation.
The current study investigated the relationship between duration of outlet obstruction, magnitude of bladder mass, and functional dysfunction on the rabbit urinary bladder. Following the production of obstruction with the "cuff model", bladder wet weight increased to twice control weight within one week, and then slowly to four times control weight by one month, and remained at this level for the six month period. Bladder capacity decreased significantly by one week but returned to control volumes by one month. The in vitro ability of the bladder to empty in response to field stimulation and bethanechol decreased significantly in the one and two week obstructed bladders and remained decreased for six months. One of the major observations of this study was the relatively large variation of bladder weight and histology observed for the one to six month obstructed rabbits. Although the bladders with mild mass increase (less than 3 gm./kg. body weight) had normal distribution of urothelium and muscular elements, the bladders with moderate mass increase (3 to 6 gm./kg.) had thick extrinsic connective tissue deposits and the bladders with severe mass increase (greater than 6 gm./kg.) had thick extrinsic and intrinsic connective tissue deposits and muscular degeneration. The percentage occurrence of mild, moderate and severe mass increase was approximately the same (58%, 30% and 12%, respectively) for the one, three, and six month groups. The bladders with mild mass increase had normal bladder capacities and increased pressure responses to field stimulation and bethanechol. The bladders with moderate-to-severe mass increase showed enlarged bladder capacities and had progressively smaller pressure responses. As the magnitude of bladder mass increased, the ability of the bladder to empty in response to field stimulation and bethanechol decreased proportionally. We conclude that the functional impairment of the bladder is related to the amount of extrinsic and intrinsic connective tissue and the degree of muscle degeneration.
Aims:The aims of the present study were to investigate voiding patterns, tissue constituents and the expressions of cyclooxygenase-2 (COX-2) and nitric oxide synthase (NOS) involved in ketamine-induced ulcerative cystitis in rat urinary bladder. Methods: Thirty Sprague-Dawley rats were distributed into three groups which received saline or ketamine (25 mg/kg/day) for a period of 14 and 28 days. In each group, cystometry was performed weekly and the concentration of ketamine and its metabolites (norketamine) was assayed. Paraffin-embedded sections were stained with Masson's trichrome stain, and ketamine-induced morphological changes were examined. Western blot analyses were carried out to examine the expressions of COX-2 and different NOS isoforms in bladder tissues. Immunofluorescence study was done to evaluate the expressions of COX-2 and macrophage infiltration (stained with ED-1 macrophage cell surface antigen) within the bladder. Results: Ketamine treatment resulted in bladder hyperactivity and the non-voiding contractions were significantly increased. The urine concentrations of ketamine and norketamine were much higher in ketamine-treated group. Moreover, ulcerated urothelium and mononuclear cell infiltration were noted in ketamine-treated group. These alterations in urodynamic functions and tissue constituents were accompanied by increases in the expression of COX-2. Two NOS isoforms (iNOS and eNOS) were also overexpressed, but no significant change was observed for nNOS. COX-2 positive stained cells were significantly increased. Meanwhile, increased amounts of ED-1 positive stained macrophages were present and most of COX-2 expressed cells were co-stained with ED-1 in the early stage of ketamine treatment. Conclusions: Ketamine treatment affected bladder tissues by enhancing interstitial fibrosis and accelerating macrophages infiltration. Ketamine also initiated the up-regulations of COX-2 and iNOS and eNOS expressions. These up-regulated enzymes might play an important role in contributing to ketamine-induced alterations in micturition patterns and ulcerative cystitis.
These findings demonstrate that bladder function and structure can be significantly affected by modulating the circulating estrogen level. In addition, estrogen given in pharmacological doses can have a significant hypertrophic effect on bladder smooth muscle, resulting in increased contractile function.
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