Transcript （HbA1C 6.0%未満）、または通常療法

Journal Club
Whitmer RA, Karter AJ, Yaffe K, Quesenberry CP Jr, Selby JV.
Hypoglycemic episodes and risk of dementia in older patients with type 2 diabetes
mellitus.
JAMA. 2009 Apr 15;301(15):1565-72.
Young LH, Wackers FJ, Chyun DA, Davey JA, Barrett EJ, Taillefer R, Heller GV,
Iskandrian AE, Wittlin SD, Filipchuk N, Ratner RE, Inzucchi SE; DIAD Investigators.
Cardiac outcomes after screening for asymptomatic coronary artery disease in patients
with type 2 diabetes: the DIAD study: a randomized controlled trial.
JAMA. 2009 Apr 15;301(15):1547-55.
2009年5月7日 8:30-8:55
８階 医局
埼玉医科大学 総合医療センター 内分泌・糖尿病内科
Department of Endocrinology and Diabetes,
Saitama Medical Center, Saitama Medical University
松田 昌文
Matsuda, Masafumi
Diabetes Center, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
Couri et al describe long-term follow-up and insulin secretion status of patients
from their original study, in which they performed nonmyeloablative autologous
stem cell transplantation to treat very recent–onset type 1 diabetes.
Clinicians are left with trying to achieve an HbA1c goal of less than 7%, which
reduces microvascular and cardiovascular disease over time, but no rationale to
try to achieve an HbA1c of less than6%if more than lifestyle changes are required.
Based on an analysis of registry data from a large ongoing epidemiologic cohort,
the authors report that among elderly patients with type 2 diabetes who had no
documented prior diagnoses of dementia, cognitive impairment, or memory
complaints, episodes of hypoglycemia severe enough to result in emergency
department or hospital treatment were associated with increased risk of being
diagnosed with dementia.
The DIAD study results suggest that more aggressive screening for coronary
artery disease does not appear to improve the outcome of asymptomatic
individuals with type 2 diabetes.
In the observational study by Kosiborod et al, the occurrence of hypoglycemia
was associated with higher mortality among patients who did not receive insulin
(compared with patients who did not experience hypoglycemia), but not in
patients who were treated with insulin.
Hypoglycemic Episodes and Risk of Dementia in Older Patients With Type 2
Diabetes Mellitus
JAMA. 2009;301(15):1565-1572.
JAMA Report Video
This JAMA Report summarizes key findings from the article in video format and includes an
interview with one of the authors. The video script and links to the video are available at
http://pubs.ama-assn.org/media/2009j/0414.dtl#vnrscript.
ACCORD ～HbA1Cの推移～
（%）
9.0
中央値
バーは四分位範
囲
8.5
HbA1C
8.0
7.5
通常療法
7.0
6.5
強化療法
6.0
0
症例数
通常療法
強化療法
0
1
2
5,109
5,119
4,774
4,768
4,588
4,585
3
4
観察期間
3,186
3,165
1,744
1,706
5
455
476
6 （年）
436
471
2型糖尿病10,251例（平均年齢62.2歳）を無作為に強化療法群（HbA1C 6.0%未満、SBP 120mmHg未満）または通常
療法（HbA1C 7.0～7.9%、SBP 140mmHg）に割り付けた。なお、脂質代謝異常に関してはシンバスタチンでLDL-Cをコ
ントロールした状態でフェノフィブラートまたはプラセボを二重盲験下で投与した。そして、非致死性心筋梗塞、非致死性
脳卒中、心血管死の複合エンドポイントを主要評価項目とし、平均3.5年のフォローアップを行った。
ACCORD Study Group：N.Engl.J.Med.,358,2545,2008.
ACCORD ～主要評価項目～
（%）
25
累 20
積
イ 15
ベ
ン
ト 10
発
症 5
率
0
症例数
強化療法
通常療法
ハザード比
95%信頼区間
p値
0.90
0.78,1.04
0.16
通常療法
強化療法
0
1
2
5,128
5,123
4,843
4,827
4,390
4,262
3
観察期間
2,839
2,702
4
5
1,337
1,186
475
440
6 （年）
448
395
【主要評価項目】
初発の非致死心筋梗塞または非致死脳卒中、心血管死（心筋梗塞、心不全、不整脈、侵襲的冠インターベンション、
心血管以外の手術後による心血管イベント、脳卒中、症状発現24時間以内における突然の心血管疾患死または
心血管疾患が推定される死亡、他の血管疾患による死亡など）の複合エンドポイント
2型糖尿病10,251例（平均年齢62.2歳）を無作為に強化療法群（HbA1C 6.0%未満、SBP 120mmHg未満）または通常
療法（HbA1C 7.0～7.9%、SBP 140mmHg）に割り付けた。なお、脂質代謝異常に関してはシンバスタチンでLDL-Cをコ
ントロールした状態でフェノフィブラートまたはプラセボを二重盲験下で投与した。そして、非致死性心筋梗塞、非致死性
脳卒中、心血管死の複合エンドポイントを主要評価項目とし、平均3.5年のフォローアップを行った。
ACCORD Study Group：N.Engl.J.Med.,358,2545,2008.
ACCORD ～総死亡～
（%）
25
累
積
イ
ベ
ン
ト
発
症
率
20
ハザード比
95%信頼区間
p値
15
1.22
1.01,1.46
0.04
強化療法
10
5
通常療法
0
症例数
強化療法
通常療法
0
1
2
3
観察期間
4
5
5128
5123
4972
4971
4803
4700
3250
3180
1748
1642
523
499
6 （年）
506
480
2型糖尿病10,251例（平均年齢62.2歳）を無作為に強化療法群（HbA1C 6.0%未満、SBP 120mmHg未満）または通常
療法（HbA1C 7.0～7.9%、SBP 140mmHg）に割り付けた。なお、脂質代謝異常に関してはシンバスタチンでLDL-Cをコ
ントロールした状態でフェノフィブラートまたはプラセボを二重盲験下で投与した。そして、非致死性心筋梗塞、非致死性
脳卒中、心血管死の複合エンドポイントを主要評価項目とし、平均3.5年のフォローアップを行った。
ACCORD Study Group：N.Engl.J.Med.,358,2545,2008.
平均HbA1C
ADVANCE trial ～HbA1Cの推移～
（%）
10.0
9.5
9.0
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
p<0.001
通常療法
強化療法
0.0
0
HbA1C値
通常療法
強化療法
6
12
7.32 7.30
7.01 6.93
18
24
30 36 42
観察期間
48
7.29
6.70
7.29
6.53
7.31
6.50
54
60
66 （ヵ月）
7.33 7.29
6.52 6.53
2型糖尿病患者11,140例を通常療法群と強化療法群に無作為に割り付け、5年間（中央値）にわたり大血管症と細小血管
症の発症を検討した。なお、強化療法群はグリクラジド徐放性製剤30～120mg/日に他の糖尿病治療薬を併用し、
HbA1C 6.5%以下を目指す。
The ADVANCE Collaborative Group：N.Engl.J.Med.,358,2560,2008.
ADVANCE trial ～大血管症＋細小血管症への影響～
（%）
25
通常療法
累 20
積
イ 15
ベ
ン
ト
発 10
症
率 5
0
症例数
強化療法
通常療法
強化療法
0
6
12
18
24
ハザード比
95%信頼区間
p値
0.90
0.82,0.98
0.01
30 36 42
観察期間
48
54 60
5,570 5,457 5,369 5,256 5,100 4,957 4,867 4,756 4,599 4,044 1,883
5,569 5,448 5,342 5,240 5,065 4,903 4,808 4,703 4,545 3,992 1,921
66 （ヵ月）
447
470
2型糖尿病患者11,140例を通常療法群と強化療法群に無作為に割り付け、5年間（中央値）にわたり大血管症と細小血管
症の発症を検討した。なお、強化療法群はグリクラジド徐放性製剤30～120mg/日に他の糖尿病治療薬を併用し、
HbA1C 6.5%以下を目指す。
The ADVANCE Collaborative Group：N.Engl.J.Med.,358,2560,2008.
ADVANCE trial ～総死亡への影響～
（%）
25
累
積
イ
ベ
ン
ト
発
症
率
ハザード比
95%信頼区間
p値
0.93
0.83,1.06
0.28
20
通常療法
15
10
強化療法
5
0
0
6
12
18
24
30 36 42
観察期間
48
54
60
症例数
強化療法 5,571 5,533 5,490 5,444 5,411 5,361 5,312 5,246 5,189 4,653 2,211
通常療法 5,569 5,537 5,503 5,445 5,399 6,354 5,301 5,237 5,178 4,643 2,240
66 （ヵ月）
523
544
2型糖尿病患者11,140例を通常療法群と強化療法群に無作為に割り付け、5年間（中央値）にわたり大血管症と細小血管
症の発症を検討した。なお、強化療法群はグリクラジド徐放性製剤30～120mg/日に他の糖尿病治療薬を併用し、
HbA1C 6.5%以下を目指す。
The ADVANCE Collaborative Group：N.Engl.J.Med.,358,2560,2008.
VADT ～HbA1Cの推移～
（%）
10.5
10.0
9.5
9.0
8.5
8.0
7.5
7.0
*
HbA1C
8.4%
6.5
6.0
5.5 ～
～
0
*
6.9%
通常療法
強化療法
登録時
1
*中央値
2
3
観察期間
4
5
6
（年）
2型糖尿病1,791例を無作為にロシグリタゾンを中心とした治療により強化療法群（HbA1C 6.0%未満）、または通常療法
（HbA1C 8.0～9.0%）に割り付けた。そして、主要心血管イベント（心血管死、心筋梗塞、脳卒中、うっ血性心不全、手術で
きない冠動脈疾患）、虚血部位の切断、冠動脈疾患へのインターベンション、末梢血管疾患を主要評価項目とした。
Duckworth W et al: N Engl J Med 360:129-39, 2009
VADT ～非致死性イベント～
100
80
非 60
発
症
率 40
通常療法
強化療法
ハザード比
95%信頼区間
p値
0.845
0.704,1.016
0.0725
20
0
0
1
2
3
4
観察期間
5
6
7 （年）
2型糖尿病1,791例を無作為にロシグリタゾンを中心とした治療により強化療法群（HbA1C 6.0%未満）、または通常療法
（HbA1C 8.0～9.0%）に割り付けた。そして、主要心血管イベント（心血管死、心筋梗塞、脳卒中、うっ血性心不全、手術で
きない冠動脈疾患）、虚血部位の切断、冠動脈疾患へのインターベンション、末梢血管疾患を主要評価項目とした。
Duckworth W et al: N Engl J Med 360:129-39, 2009
VADT ～総死亡～
100
80
非 60
発
症
率 40
通常療法
強化療法
20
ハザード比
95%信頼区間
p値
1.065
0.801,1.416
0.67
0
0
1
2
3
4
観察期間
5
6
7 （年）
2型糖尿病1,791例を無作為にロシグリタゾンを中心とした治療により強化療法群（HbA1C 6.0%未満）、または通常療法
（HbA1C 8.0～9.0%）に割り付けた。そして、主要心血管イベント（心血管死、心筋梗塞、脳卒中、うっ血性心不全、手術で
きない冠動脈疾患）、虚血部位の切断、冠動脈疾患へのインターベンション、末梢血管疾患を主要評価項目とした。
Duckworth W et al: N Engl J Med 360:129-39, 2009
強化療法群の低血糖発現率が高かった
ACCORD ～医療処置を必要とする重症低血糖～
（%）
25
重
症
低
血
糖
発
現
率
20
強化療法
15
10
5
通常療法
0
強化療法群
通常療法群
0
1
2
3
4
5
6
5,128
5,123
4,601
4,699
4,494
4,589
2,965
3,066
1,549
1,556
437
478
414
452
7
（年）
ACCORD Study Group：ADA 68th Scientific Sessions,2008,San Francisco.
強化療法群の低血糖発現率が高かった
ACCORD
～無作為割り付け後の使用薬剤の総死亡に対するハザード比～
（ベースライン時患者背景で補正）
ハ
ザ
ー
ド
比
2.25
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
リ
ス
ク
増
大
リ
ス
ク
減
少
英語で表記している薬剤は日本では未発売です。
ACCORD Study Group：ADA 68th Scientific Sessions,2008,San Francisco.
低血糖は心血管死の予測因子である
VADT 各因子と心血管死の関係
ハザード比
95%信頼区間
p値
低血糖
4.042（1.449，11.276）
0.01
HbA1C
1.213（1.038，1.417）
0.02
HDL
0.699（0.536，0.910）
0.01
年齢
2.090（1.518，2.877）
<0.01
冠動脈疾患
イベントの既往
3.116（1.744，5.567）
<0.01
0
2
4
6
8
10
12
2型糖尿病1,791例を強化療法群（目標値：HbA1C 6.0%未満）、または通常療法群（目標値：HbA1C 8.0～9.0%）に割り
付けた。そして、主要心血管イベント（心血管死、心筋梗塞、脳卒中、うっ血性心不全、手術できない冠動脈疾患）、虚血
部位の切断、冠動脈疾患へのインターベンション、末梢血管疾患を主要評価項目とした。
Abraira C.：ADA 68th Scientific Sessions,2008,San Francisco.
Original Article
Long-Term Effect of Diabetes and Its Treatment on
Cognitive Function
The Diabetes Control and Complications Trial/Epidemiology of Diabetes
Interventions and Complications (DCCT/EDIC) Study Research Group
The members of the writing committee — Alan M. Jacobson, M.D., and Gail Musen, Ph.D.,
Joslin Diabetes Center and Harvard Medical School, Boston; Christopher M. Ryan, Ph.D., and
Nancy Silvers, R.N., University of Pittsburgh School of Medicine, Pittsburgh; Patricia Cleary,
M.S., and Barbara Waberski, M.S., George Washington University, Rockville, MD; Amanda
Burwood, B.S., and Katie Weinger, Ed.D., Joslin Diabetes Center, Boston; Meg Bayless, R.N.,
University of Iowa College of Medicine, Iowa City; William Dahms, M.D. (deceased), Case
Western Reserve University, Cleveland; and Judith Harth, R.N., University of Western Ontario
Schulich School of Medicine, London, ON, Canada — and the DCCT/EDIC Study Research
Group assume responsibility for the overall content and integrity of the article.
N Engl J Med
Volume 356(18):1842-1852
May 3, 2007
No evidence of substantial long-term declines in cognitive function
Effects of DCCT Treatment Group, Severe Hypoglycemia, and Glycated Hemoglobin on
Changes in Cognition, from Entry into DCCT to Year 12 in the EDIC Study
The bars show the changes within
cognitive domains between cognitive
testing at baseline in DCCT and
follow-up testing (a mean of 18 years
after baseline) expressed as changes
in z scores for intensive versus
conventional treatment (Panel A),
frequency of episodes of severe
hypoglycemia (coma or seizure)
(Panel B), and mean glycated
hemoglobin values (Panel C).
Across the three groups, higher levels
of glycated hemoglobin were
associated with moderate declines in
psychomotor efficiency (P<0.001) and
motor speed (P=0.001), but no other
cognitive domain was affected
significantly.
Cognitive domains are numbered as
follows: 1, problem solving; 2,
learning; 3, immediate memory; 4,
delayed recall; 5, spatial information;
6, attention; 7, psychomotor
efficiency; and 8, motor speed.
Division of Research, Section of
Etiology and Prevention, Kaiser
Permanente, Oakland, California (Drs
Whitmer, Karter, Quesenberry, and
Selby); Departments of Psychiatry,
Neurology and Epidemiology,
University of California, San Francisco
(Dr Yaffe).
JAMA. 2009;301(15):1565-1572
Background and Aim
Although acute hypoglycemia may be
associated with cognitive impairment in
children with type 1 diabetes, no studies to
date have evaluated whether hypoglycemia
is a risk factor for dementia in older patients
with type 2 diabetes.
To determine if hypoglycemic episodes
severe enough to require hospitalization are
associated with an increased risk of
dementia in a population of older patients
with type 2 diabetes followed up for 27 years.
Methods
Design, Setting, and Patients: A longitudinal cohort study
from 1980-2007 of 16,667 patients with a mean age of 65
years and type 2 diabetes who are members of an integrated
health care delivery system in northern California.
Main Outcome Measure: Hypoglycemic events from 19802002 were collected and reviewed using hospital discharge
and emergency department diagnoses. Cohort members with
no prior diagnoses of dementia, mild cognitive impairment, or
general memory complaints as of January 1, 2003, were
followed up for a dementia diagnosis through January 15,
2007. Dementia risk was examined using Cox proportional
hazard regression models, adjusted for age, sex, race/
ethnicity, education, body mass index, duration of diabetes,
7-year mean glycated hemoglobin, diabetes treatment,
duration of insulin use, hyperlipidemia, hypertension,
cardiovascular disease, stroke, transient cerebral ischemia,
and end-stage renal disease.
Cox Regression
打ち切り症例を含む生存データについて、従属変数に事象発生までの時間を使用す
る有用な回帰モデルが1972年David Coxによって紹介され、比例ハザードモデルあ
るいはCoxのモデルと呼ばれている。
Population
Characteristics by
Hospital or
Emergency
DepartmentAssociated
Hypoglycemia
Whitmer, R. A. et al. JAMA 2009;301:1565-1572.
Copyright restrictions may
apply.
Frequency of Hypoglycemic Episodes by Dementia Status
Whitmer, R. A. et al. JAMA 2009;301:1565-1572.
Copyright restrictions may
apply.
Hypoglycemia and Risk of Incident Dementiaa
Whitmer, R. A. et al. JAMA 2009;301:1565-1572.
Copyright restrictions may
apply.
Subgroup Analyses of Hypoglycemia and Dementia Riska
Copyright restrictions may
apply.
Whitmer, R. A. et al. JAMA 2009;301:1565-1572.
Results
At least 1 episode of hypoglycemia was diagnosed in 1465 patients
(8.8%) and dementia was diagnosed in 1822 patients (11%) during
follow-up; 250 patients had both dementia and at least 1 episode of
hypoglycemia (16.95%). Compared with patients with no
hypoglycemia, patients with single or multiple episodes had a
graded increase in risk with fully adjusted hazard ratios (HRs): for
1 episode (HR, 1.26; 95% confidence interval [CI], 1.10-1.49); 2
episodes (HR, 1.80; 95% CI, 1.37-2.36); and 3 or more episodes (HR,
1.94; 95% CI, 1.42-2.64). The attributable risk of dementia between
individuals with and without a history of hypoglycemia was 2.39%
per year (95% CI, 1.72%-3.01%). Results were not attenuated when
medical utilization rates, length of health plan membership, or time
since initial diabetes diagnosis were added to the model. When
examining emergency department admissions for hypoglycemia
for association with risk of dementia (535 episodes), results were
similar (compared with patients with 0 episodes) with fully
adjusted HRs: for 1 episode (HR, 1.42; 95% CI, 1.12-1.78) and for 2
or more episodes (HR, 2.36; 95% CI, 1.57-3.55).
Limitation
A possible weakness is that our dementia diagnoses are based on clinical
diagnoses obtained from electronic medical records, rather than the results of
standardized neurological assessments administered periodically to all cohort
members.
Another potential concern is that due to the observational nature of our cohort
study, we cannot be certain of the temporality of our findings, and cognitive
problems due to undiagnosed dementia may have contributed to the occurrence
of hypoglycemia. However, individuals with diagnoses of dementia, mild cognitive
impairment, or general memory impairment before 2003 were excluded. In
addition, we designed the study to increase the temporal separation of earlier
hypoglycemic episodes from later occurrences of dementia and also conducted
analyses with further lags between exposure to hypoglycemia and the beginning
of observation for incident dementia. These lagged-model findings demonstrated
similar associations. Even when considering only hypoglycemic episodes during
the first 5 years of the study, when the patients were between the ages of 52 and
57 years (when dementia is highly unlikely), there was still an association with an
elevated risk of dementia more than 2 decades later.
Finally, our study involves the association between severe hypoglycemic
episodes and risk of dementia; implications from our study do not address the
role of less severe but more frequent episodes of hypoglycemia on dementia risk.
The clinical significance of minor hypoglycemic episodes on dementia risk is
unknown.
Conclusions
Among older patients with type 2
diabetes, a history of severe
hypoglycemic episodes was associated
with a greater risk of dementia. Whether
minor hypoglycemic episodes increase
risk of dementia is unknown.
Department of Internal Medicine, Section of
Cardiovascular Medicine (Drs Young and Wackers
and Ms Davey) and Section of Endocrinology (Dr
Inzucchi), Yale University School of Medicine, New
Haven, Connecticut; College of Nursing at the
College of Dentistry, New York University, New
York (Dr Chyun); Department of Endocrinology,
University of Virginia, Charlottesville (Dr Barrett);
Medecine Nucleaire, University of Montreal,
Montreal, Quebec, Canada (Dr Taillefer);
Department of Cardiology, Hartford Hospital,
Hartford, Connecticut (Dr Heller); Department of
Cardiology, University of Alabama, Birmingham
(Dr Iskandrian); Department of Endocrinology,
University of Rochester, Rochester, New York (Dr
JAMA. 2009;301(15):1547-1555
Background and Aim
Coronary artery disease (CAD) is the
major cause of mortality and morbidity in
patients with type 2 diabetes. But the
utility of screening patients with type 2
diabetes for asymptomatic CAD is
controversial.
To assess whether routine screening for
CAD identifies patients with type 2
diabetes as being at high cardiac risk and
whether it affects their cardiac outcomes.
Methods
The Detection of Ischemia in Asymptomatic
Diabetics (DIAD) study is a randomized
controlled trial in which 1123 participants with
type 2 diabetes and no symptoms of CAD were
randomly assigned to be screened with
adenosine-stress radionuclide myocardial
perfusion imaging (MPI) or not to be screened.
Participants were recruited from diabetes clinics
and practices and prospectively followed up
from August 2000 to September 2007. Main
Outcome Measure is Cardiac death or nonfatal
myocardial infarction (MI).
Flow of Study Participants
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Young, L. H. et al. JAMA 2009;301:1547-1555.
Baseline Characteristics
According to Randomization
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Young, L. H. et al. JAMA 2009;301:1547-1555.
Events in No-Screening vs Screening Group
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Young, L. H. et al. JAMA 2009;301:1547-1555.
Cumulative Incidence of Cardiac Events in Participants With Type 2 Diabetes Without
Symptomatic or Previously Diagnosed Coronary Artery Disease
A, Cumulative incidence of cardiac events in 561 participants randomized to systematic baseline
screening with stress myocardial perfusion imaging (MPI) and 562 participants randomized to receive no
screening. B, Cumulative incidence of cardiac events according to results of systematic screening with
stress MPI: normal, small defect, moderate or large defect, and nonperfusion abnormality. No cardiac
events occurred in participants who were randomized to but did not complete screening MPI. The y-axis
scale in blue indicates range from 0 to 0.06.
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Young, L. H. et al. JAMA 2009;301:1547-1555.
Events According to Findings of Screening Myocardial Perfusion Imaging (n = 522)
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Young, L. H. et al. JAMA 2009;301:1547-1555.
Follow-up and Medication Use
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Young, L. H. et al. JAMA 2009;301:1547-1555.
Factors Associated With Primary
Events
Young, L. H. et al. JAMA 2009;301:1547-1555.
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Results
The cumulative cardiac event rate was 2.9% over a mean (SD)
follow-up of 4.8 (0.9) years for an average of 0.6% per year.
Seven nonfatal MIs and 8 cardiac deaths (2.7%) occurred among
the screened group and 10 nonfatal MIs and 7 cardiac deaths
(3.0%) among the not-screened group (hazard ratio [HR], 0.88;
95% confidence interval [CI], 0.44-1.88; P=.73). Of those in the
screened group, 409 participants with normal results and 50
with small MPI defects had lower event rates than the 33 with
moderate or large MPI defects; 0.4% per year vs 2.4% per year
(HR, 6.3; 95% CI, 1.9-20.1; P=.001). Nevertheless, the positive
predictive value of having moderate or large MPI defects was
only 12%. The overall rate of coronary revascularization was low
in both groups: 31 (5.5%) in the screened group and 44 (7.8%) in
the unscreened group (HR, 0.71; 95% CI, 0.45-1.1; P=.14). During
the course of study there was a significant and equivalent
increase in primary medical prevention in both groups.
Limitation
The cardiac event rates were significantly lower than originally anticipated at the
time of the design of the study and therefore the DIAD study does not have the
power to exclude a small difference between the screened and unscreened
participants. Based on the observed cardiac event rate, we would estimate that
the study only had 14% power to detect a 20% difference between the 2 groups. A
3- to 4-fold larger study would be required to exclude such a difference, and it is
not clear that a reduction in cardiac events from 0.6% to 0.5% per year even if
proved would justify cardiac screening.
Another potential limitation to consider is that nonprotocol stress tests were done
during follow-up when clinically indicated in both groups. In addition, screening
led to only a modest reduction in subsequent diagnostic testing. Testing was
typically performed to evaluate potential cardiac symptoms but may have also
been undertaken for risk stratification in some participants. In the no-screening
group, such testing represents a crossover to a physician-directed screening
strategy and theoretically might have counter-balanced a benefit of protocolmandated systematic screening. However, because the DIAD study did not
prohibit physician directed cardiac evaluation, the results are more applicable to
current day medicine in which patients are often evaluated for symptoms or
preoperative risk stratification or when considered particularly high risk by their
physicians.
Conclusion
In this contemporary study
population of patients with diabetes,
the cardiac event rates were low and
were not significantly reduced by
MPI screening for myocardial
ischemia over 4.8 years.
Trial Registration clinicaltrials.gov
Identifier: NCT00769275