***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background and Purpose — Impaired glucose tolerance (IGT)–a prediabetic state – is an important risk factor for atherosclerosis . Acarbose , an & agr;-glucosidase inhibitor , was shown in the placebo-controlled prospect i ve study to prevent noninsulin-dependent diabetes mellitus ( STOP-NIDDM ) trial to reduce the risk of diabetes by 36 % in IGT subjects . This article reports on a placebo-controlled subgroup analysis of the STOP-NIDDM study to examine the efficacy of acarbose to slow progression of intima-media thickness ( IMT ) in subjects with IGT . Methods — One hundred thirty-two IGT subjects were r and omized to placebo ( n=66 ) or acarbose ( n=66 ) 100 mg 3 times daily ; the study duration was at least 3 years , mean follow-up time 3.9 ( SD 0.6 ) years . Carotid IMT was determined at study entry and the end of the trial . The intent-to-treat analysis included 56 subjects in the acarbose and 59 in the control group who had a baseline and endpoint measurement . Results — A significant reduction of the progression of IMTmean was observed in the acarbose group versus placebo . After an average time of 3.9 years , IMTmean increased by 0.02 ( 0.07 ) mm in the acarbose group versus 0.05 ( 0.06 ) mm in the placebo group ( P = 0.027 ) . The annual increase of IMTmean was reduced by ≈50 % in the acarbose group versus placebo . Multiple linear regression revealed IMT progression as significantly related to acarbose intake . Conclusions — Acarbose slows progression of IMT in IGT subjects , a high-risk population for diabetes and atherosclerosis . This is the first placebo-controlled prospect i ve subgroup analysis , demonstrating that counterbalancing of postpr and ial hyperglycemia may be vasoprotective CONTEXT The worldwide explosive increase in type 2 diabetes mellitus and its cardiovascular morbidity are becoming major health concerns . OBJECTIVE To evaluate the effect of decreasing postpr and ial hyperglycemia with acarbose , an alpha-glucosidase inhibitor , on the risk of cardiovascular disease and hypertension in patients with impaired glucose tolerance ( IGT ) . DESIGN , SETTING , AND PARTICIPANTS International , multicenter double-blind , placebo-controlled , r and omized trial , undertaken in hospitals in Canada , Germany , Austria , Norway , Denmark , Sweden , Finl and , Israel , and Spain from July 1998 through August 2001 . A total of 1429 patients with IGT were r and omized with 61 patients ( 4 % ) excluded because they did not have IGT or had no postr and omization data , leaving 1368 patients for a modified intent-to-treat analysis . Both men ( 49 % ) and women ( 51 % ) participated with a mean ( SD ) age of 54.5 ( 7.9 ) years and body mass index of 30.9 ( 4.2 ) . These patients were followed up for a mean ( SD ) of 3.3 ( 1.2 ) years . INTERVENTION Patients with IGT were r and omized to receive either placebo ( n = 715 ) or 100 mg of acarbose 3 times a day ( n = 714 ) . MAIN OUTCOME MEASURES The development of major cardiovascular events ( coronary heart disease , cardiovascular death , congestive heart failure , cerebrovascular event , and peripheral vascular disease ) and hypertension ( > or = 140/90 mm Hg ) . RESULTS Three hundred forty-one patients ( 24 % ) discontinued their participation prematurely , 211 in the acarbose-treated group and 130 in the placebo group ; these patients were also followed up for outcome parameters . Decreasing postpr and ial hyperglycemia with acarbose was associated with a 49 % relative risk reduction in the development of cardiovascular events ( hazard ratio [ HR ] , 0.51 ; 95 % confidence interval [ CI ] ; 0.28 - 0.95 ; P = .03 ) and a 2.5 % absolute risk reduction . Among cardiovascular events , the major reduction was in the risk of myocardial infa rct ion ( HR , 0.09 ; 95 % CI , 0.01 - 0.72 ; P = .02 ) . Acarbose was also associated with a 34 % relative risk reduction in the incidence of new cases of hypertension ( HR , 0.66 ; 95 % CI , 0.49 - 0.89 ; P = .006 ) and a 5.3 % absolute risk reduction . Even after adjusting for major risk factors , the reduction in the risk of cardiovascular events ( HR , 0.47 ; 95 % CI , 0.24 - 0.90 ; P = .02 ) and hypertension ( HR , 0.62 ; 95 % CI , 0.45 - 0.86 ; P = .004 ) associated with acarbose treatment was still statistically significant . CONCLUSION This study suggests that treating IGT patients with acarbose is associated with a significant reduction in the risk of cardiovascular disease and hypertension OBJECTIVE Whereas new diagnostic criteria based on a fasting plasma glucose ( FPG ) of > 126 mg/dl ( 7.8 mmol/l ) have improved the detection of diabetes , multiple reports indicate that many people with diabetes diagnosed by 2-h oral glucose tolerance test ( OGTT ) glucose measurements > or = 11.1 mmol/l ( 200 mg/dl ) would remain undiagnosed based on this FPG criteria . Thus , improved methods to detect diabetes are particularly needed for high-risk individuals . We evaluated whether the combination of FPG and HbA1c measurements enhanced detection of diabetes in those individuals at risk for diabetes with nondiagnostic or minimally elevated FPG . RESEARCH DESIGN AND METHODS We analyzed FPG , OGTT , and HbA1c data  from 244 subjects screened for participation in the Early Diabetes Intervention Program ( EDIP ) .  RESULTS Of 244 high-risk subjects studied by FPG measurements and OGTT , 24 % of the individuals with FPG levels of 5.5 - 6.0 mmol/l ( 100 - 109 mg/dl ) had OGTT-diagnosed diabetes , and nearly 50 % of the individuals with FPG levels of 6.1 - 6.9 mmol/l ( 110 - 125 mg/dl ) had OGTT-diagnosed diabetes . In the subjects with OGTT-diagnosed diabetes and FPG levels between 5.5 and 8.0 mmol/l , detection of an elevated HbA1c ( > 6.1 % or mean + 2 SDs ) led to a substantial improvement in diagnostic sensitivity over the FPG threshold of 7.0 mmol/l ( 61 vs. 45 % , respectively , P = 0.002 ) . Concordant FPG levels > or = 7.0 mmol/l ( currently recommended for diagnosis ) occurred in only 19 % of our cohort with type 2 diabetes . CONCLUSIONS Diagnostic criteria based on FPG criteria are relatively insensitive in the detection of early type 2 diabetes in at-risk subjects . HbA1c measurement improves the sensitivity of screening in high-risk individuals Context Lifestyle and pharmaceutical interventions can prevent overt diabetes in people with impaired glucose tolerance .  Oral glucose tolerance testing is the reference st and ard for identifying impaired glucose tolerance , but it is inconvenient and relatively expensive . Contribution The authors developed multivariable models that use readily available clinical variables to predict the development of diabetes . The models were more accurate than oral glucose tolerance testing alone . Adding results of oral glucose tolerance testing did not substantially improve the model 's predictions . Caution s More than half the study sample was Mexican American . Validation in other population s and translation for bedside calculation is needed before clinicians can use the model . The Editors In 1979 , the National Diabetes Data Group defined an entity called impaired glucose tolerance , which reflects a degree of glucose tolerance that , although abnormal , is considered insufficient to merit a diagnosis of diabetes mellitus ( 1 ) . This entity , which was later endorsed by the World Health Organization ( WHO ) ( 2 , 3 ) and the American Diabetes Association ( 4 ) , requires a 2-hour oral glucose tolerance test for its detection . It is important to emphasize that impaired glucose tolerance is by itself entirely asymptomatic and unassociated with any functional disability . Indeed , insulin secretion is typically greater in response to a mixed meal than in response to a pure glucose load ( 5 ) ; as a result , most persons with impaired glucose tolerance are rarely , if ever , hyperglycemic in their daily lives ( 5 , 6 ) , except when they undergo diagnostic glucose tolerance tests . Thus , the importance of impaired glucose tolerance resides exclusively in its ability to identify persons at increased risk for future disease . The st and ard method for identifying persons at high risk for developing diabetes mellitus has been to identify persons with impaired glucose tolerance without regard to other diabetes risk factors . For example , nearly all of the clinical trials on prevention of type 2 diabetes have used impaired glucose tolerance as the principal enrollment criterion . Three of these trialsthe Finnish Diabetes Prevention Study ( 7 ) , the Diabetes Prevention Program ( 8) , and the Study To Prevent Non-Insulin-Dependent Diabetes Mellitus ( STOP-NIDDM ) (9)have recently reported positive results . Therefore , a need has arisen to identify persons at high risk for diabetes so that physicians can offer them preventive interventions . Because the 2-hour oral glucose tolerance test , which is necessary for the diagnosis of impaired glucose tolerance , is time consuming , costly , and inconvenient , it becomes relevant to ask whether other , more efficient means exist for identifying persons at high risk for diabetes . A popular method of assessing the predictive discrimination of a test is to use a receiver-operating characteristic ( ROC ) curve ( 10 ) that plots the sensitivity of the test against the corresponding false-positive rate . In the present context , sensitivity refers to the percentage of persons whose initial values were above a given cut point among all persons who later developed diabetes ; false-positive rate refers to the percentage of persons whose initial values were above the cut point among persons who nevertheless remained free of diabetes . The area under the ROC curve is a measure of how well a continuous variable can predict the outcome of interest : If the sensitivity increases steeply as the threshold for diagnosis is relaxed , with only a relatively slow accumulation of false-positive results , the area under the ROC curve will be large ; conversely , if the sensitivity increases slowly as the threshold for diagnosis is relaxed , with a rapid accumulation of false-positive results , the area under the ROC curve will be correspondingly smaller . The differences in the areas under two curves may be tested to see whether the apparent superiority of one continuous variable over another is statistically significant . We have used this approach to compare the  2-hour glucose value  after an oral glucose load  to various multivariable models for predicting future diabetes . Methods Participants Our analyses are based on data gathered in the San Antonio Heart Study . The methods of this study have been described elsewhere ( 11 - 13 ) . Briefly , households were r and omly sample d from three types of neighborhoods : low , middle , and high income . Residents of these households were eligible if they were 25 to 64 years of age and not pregnant . Because the number of nonMexican-American persons residing in the low-income areas was negligible , only Mexican Americans were recruited from these neighborhoods . Stratified r and om sampling was used to recruit an approximately equal number of Mexican Americans and non-Hispanic whites from the middle-income and high-income neighborhoods . The baseline data were collected in two phases , from 1979 to 1982 and from 1984 to 1988 . A total of 5158 participants were enrolled in these two phases , representing a response rate of 65.3 % of all eligible participants from the selected households . A follow-up examination was performed 7 to 8 years after the baseline examination on 3682 persons , representing 73.7 % of the 4998 surviving study participants . The Institutional Review Board of the University of Texas Health Science Center at San Antonio approved the protocol . All participants gave informed consent . Measurements Fasting plasma glucose levels were measured for all participants ; they then drank a st and ardized 75-g glucose load ( Koladex or Orangedex , Custom Laboratories , Baltimore , Maryl and ) . The plasma glucose level was measured again 2 hours later . Although various protocol s have been used for oral glucose tolerance testing , the glucose level obtained 2 hours after the administration of the oral glucose load is the only postload value that has been used as the basis for diagnostic categories ( 1 - 4 ) ; therefore , this was the only postload value that we considered . In line with common usage , we refer to this value as the 2-hour glucose value . Diabetes was diagnosed according to WHO criteria ( fasting glucose level 7.0 mmol/L [ 126 mg/dL ] or 2-hour glucose level 11.1 mmol/L [ 200 mg/dL ] ) ( 3 ) . Persons who 
    Output:
    
There is evidence that acarbose reduces the incidence of type 2 diabetes in patients with IGT .
However , it is unclear whether this should be seen as prevention , delay or masking of diabetes .