Based on the results of the Diabetes Prevention Program Outcomes Study (DPPOS), in which metformin significantly decreased the development of diabetes in individuals with baseline fasting plasma ...glucose (FPG) concentrations of 110-125 vs. 100-109 mg/dL (6.1-6.9 vs. 5.6-6.0 mmol/L) and A1C levels 6.0-6.4% (42-46 mmol/mol) vs. <6.0% and in women with a history of gestational diabetes mellitus, it has been suggested that metformin should be used to treat people with prediabetes. Since the association between prediabetes and cardiovascular disease is due to the associated nonglycemic risk factors in people with prediabetes, not to the slightly increased glycemia, the only reason to treat with metformin is to delay or prevent the development of diabetes. There are three reasons not to do so. First, approximately two-thirds of people with prediabetes do not develop diabetes, even after many years. Second, approximately one-third of people with prediabetes return to normal glucose regulation. Third, people who meet the glycemic criteria for prediabetes are not at risk for the microvascular complications of diabetes and thus metformin treatment will not affect this important outcome. Why put people who are not at risk for the microvascular complications of diabetes on a drug (possibly for the rest of their lives) that has no immediate advantage except to lower subdiabetes glycemia to even lower levels? Rather, individuals at the highest risk for developing diabetes-i.e., those with FPG concentrations of 110-125 mg/dL (6.1-6.9 mmol/L) or A1C levels of 6.0-6.4% (42-46 mmol/mol) or women with a history of gestational diabetes mellitus-should be followed closely and metformin immediately introduced only when they are diagnosed with diabetes.
Over 700 men were assigned to radical prostatectomy or observation after receiving a diagnosis of prostate cancer, usually on the basis of elevated PSA levels. After a median of 10 years, ...between-group differences in all-cause and prostate-cancer mortality were not significant.
The treatment of early-stage prostate cancer remains controversial, especially for tumors detected by means of prostate-specific antigen (PSA) testing.
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Systematic reviews have provided inadequate information for assessing the comparative effectiveness of treatments and any associated harms.
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Although the lifetime risk of receiving a diagnosis of prostate cancer is about 17%, the risk of dying from the disease is approximately 3%, suggesting that conservative management may be appropriate for many men.
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Two randomized trials compared radical prostatectomy with observation but were conducted before PSA testing became widespread.
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One study failed to show a significant difference in overall mortality after . . .
The libRadtran software package is a suite of tools for radiative transfer calculations in the Earth's atmosphere. Its main tool is the uvspec program. It may be used to compute radiances, ...irradiances and actinic fluxes in the solar and terrestrial part of the spectrum. The design of uvspec allows simple problems to be easily solved using defaults and included data, hence making it suitable for educational purposes. At the same time the flexibility in how and what input may be specified makes it a powerful and versatile tool for research tasks. The uvspec tool and additional tools included with libRadtran are described and realistic examples of their use are given. The libRadtran software package is available from http://www.libradtran.org.
In 1997, the ADA recommended an IFG criterion for diagnosing prediabetes/intermediate hyperglycemia of FPG concentrations of 6.1–6.9 mmol/L (110–125 mg/dL). In 2003, they lowered it to 5.6–6.9 mmol/L ...(100–125 mg/dL) to equalize developing diabetes between IGT and IFG. International organizations accepted the first IFG criterion but not the second. The ADA subsequently recommended HbA1c levels for diagnosing prediabetes/intermediate hyperglycemia of 39–47 mmol/mol (5.7–6.4%) based on a model that utilized the composite risk of developing diabetes and CVD. However, the evidence that the intermediate hyperglycemia that defines prediabetes is independently associated with CVD is weak. Rather, the other risk factors for CVD in the metabolic syndrome are responsible. The WHO opined that prediabetes/intermediate hyperglycemia could not be diagnosed by HbA1c levels but the Canadians and Europeans recommended its diagnosis by values of 42–47 mmol/mol (6.0–6.4%). With the ADA criteria, approximately one-half of people are normal on re-testing, one-third spontaneously revert to normal over time and two-thirds never develop diabetes in their lifetimes. The international criteria for prediabetes/intermediate hyperglycemia increase the risk of developing diabetes and might motivate these individuals to more seriously undertake lifestyle interventions as a preventive measure.
Efforts to reduce the burden of type 2 diabetes include attempts to prevent or delay the onset of the disease. Landmark clinical trials have shown that lifestyle modification programs focused on ...weight loss can delay the onset of type 2 diabetes in subjects at high risk of developing the disease. Building on this knowledge, many community-based studies have attempted to replicate the trial results and, simultaneously, payers have begun to cover diabetes prevention services. This article focuses on the evidence supporting the premise that community prevention efforts will be successful. Unfortunately, no study has shown that diabetes can be delayed or prevented in a community setting, and efforts to replicate the weight loss achieved in the trials have been mostly disappointing. Furthermore, both the clinical trials and the community-based prevention studies have not shown a beneficial effect on any diabetes-related clinical outcome. While the goal of diabetes prevention is extremely important, the absence of any persuasive evidence for the effectiveness of community programs calls into question whether the use of public funds or national prevention initiatives should be supported at this time.
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