Prevention of Diabetes and Hypertension
Information source: Istituto Auxologico Italiano
Information obtained from ClinicalTrials.gov on October 19, 2009 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Diabetes Mellitus; Hypertension
Intervention: Diet: total fat < 5%, saturated fat < 10%, vegetables, fruit (Behavioral); Moderate exercise (30 min at least 5 times/week) (Behavioral); enalapril tablets (Drug); losartan tablets (Drug); placebo tablets (Drug)
Phase: Phase 4
Status: Not yet recruiting
Sponsored by: Istituto Auxologico Italiano Official(s) and/or principal investigator(s): Alberto Zanchetti, MD, Principal Investigator, Affiliation: Istituto Auxologico Italiano. Milan. Italy
Overall contact: Alberto Zanchetti, MD, Phone: + 3902619112894, Email: alberto.zanchetti@unimi.it
Summary
Background. Antihypertensive therapy with ß-blockers (ßBs) and diureticts (Ds) is
accompanied by a higher incidence of diabetes mellitus (DM) than therapy with ACE-inhibitors
(ACEIs) or angiotensin-receptor blockers (ARBs). Whether this difference is due to an
antidiabetogenic action of ACEIs and ARBs or to the fact that these agents are free of the
diabetogenic activity of ßBs and Ds is unknown. Prevention of DM as well as of HT is of
primary health concern.
Objectives. The primary objective of PHIDIAS is to test whether in individuals with
components of metabolic syndrome making them predisposed to DM and HT, addition of either an
ACEI or an ARB to periodically reinforced lifestyle counselling can reduce 1) onset of DM
and 2) onset of HT significantly more than lifestyle plus placebo. Secondary objectives are
1) comparing the antidiabetogenic effects of ACEI and ARB, and 2) investigating whether the
effects of ACEI and ARB on DM and HT persist at least 6 months after treatment withdrawal.
Methods. PHIDIAS is a prospective, double-blind, placebo-controlled 3-arm comparison trial.
300 general practitioners (members of SIMG with the assistance of hospital centres of SIIA)
will randomise 6000 untreated individuals aged 40-75 years, with SBP 130-139 or DBP 85-89
mmHg, fasting glucose (FG) 100-125 mg/dl, waist circumference >= 102 (M) or >= 88 cm (W), to
three blinded treatments, given in addition to lifestyle advise: 1) Placebo; 2) the ACE
Enalapril (10 mg, then 20 mg od); 3) the ARB Losartan (50 mg, then 100 mg od).Double-blind
treatment will be maintained until 500 cases of DM are observed (presumably average of 36
months) (Treatment Phase: control visits, BP, FG every 6 months). This will be followed by a
6-month Withdrawal Phase (active treatment substituted by placebo). Primary outcomes are DM
(FG >= 126 mg/dl) and HT (SBP >= 140 or DBP >= 90 mmHg) on 2 consecutive visits. PHIDIAS
will be governed by a Steering Committee assisted by a blinded Event Adjudicating Committee
and an independent DMSB.
Expected results. The sample size is adequate (alfa 5%, power 90%) to evaluate whether
incident DM (expected rate 3. 5%/year) or incident HT is reduced 25% by ACEI and ARB versus
placebo (primary hypothesis) and whether either the ACEI or the ARB reduces incident DM by
30% more than the other agent.
Clinical Details
Official title: Prevention of Hypertension Incidence and Diabetes Italian Assessment Study. Therapeutic Strategies of Prevention of Diabetes and Hypertension in Subjects With Metabolic Syndrome and High-Normal Blood Pressure.
Study design: Prevention, Randomized, Double-Blind, Placebo Control, Parallel Assignment, Safety/Efficacy Study
Primary outcome: Time to first event of: new diabetes or initiation of any antidiabetic treatment during the treatment period of the trialnew hypertension or initiation of any antihypertensive treatment during the treatment period of the trial.
Secondary outcome: Time to first event (during the treatment phase) of: new diabetes or new hypertension, which comes firstmajor cardiovascular events (myocardial infarction, stroke, cardiovascular death, heart failure, new documented angina, revascularization procedures ) plus death by non-cardiovascular causes variations of SBP and DBP during the treatment phase and, separately, during the withdrawal phase variations fasting blood glucose during the treatment phase and, separately, during the withdrawal phase estimated creatinine clearance lower than 60 ml/min in subjects with values >= 60 ml/min at baseline serious adverse effects. Incidence at the end of the final 6-month withdrawal phase of:new diabetes new hypertension variations of SBP and DBP variations of fasting blood glucose.
Detailed description:
1. Background and rationale
1. Evidence available Data obtained from observational studies have shown that
subjects with hypertension have an increased prevalence of type II diabetes
mellitus compared to normotensives, and that the association between diabetes and
hypertension represents a markedly increased risk of cardiovascular disease (1).
Also the recent overview of the Blood Pressure Lowering Treatment Trialists'
Collaboration indicates that the risks for stroke, coronary events, heart failure,
and cardiovascular death are about twice as large in hypertensives with diabetes
than in hypertensives without diabetes, independently of absence of treatment or
use of different antihypertensive regimens (2). On the other hand, a number of
observational and randomised intervention trials has shown that antihypertensive
therapy may increase the risk of developing new diabetes mellitus in hypertensives
patients. This evidence has been reviewed and meta-analysed in several recent
papers (3,4). In brief, of 13 large randomised trials of antihypertensive therapy,
12 have shown a greater incidence of new diabetes mellitus in the treatment arms
using thiazide diuretics or beta-blockers (and often the two types of agent in
association) than in the treatment arms based on angiotensin converting enzyme
inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) or calcium antagonists
(CAs) (often with addition of thiazides and sometimes of beta-blockers) (3).
Furthermore, a recent review analysed 48 groups of subjects without diabetes
mellitus at the time of randomization in 22 clinical trials. 17 of such trials
enrolled patients with hypertension, 3 enrolled high risk patients, and only 1
enrolled patients with heart failure. The primary outcome was represented by
incident diabetes mellitus. Overall, the antihypertensive classes that were found
to be associated with newly developed diabetes mellitus were, in increasing order,
ACEIs, ARBs, followed by CAs and placebo (4). It is debated whether thiazide
diuretics and beta-blockers are really diabetogenic, by exaggerating or
accelerating the time-dependent tendency to develop diabetes, and whether ACEIs
and ARBs are antidiabetogenic by retarding this normal trend, or simply lack the
diabetogenic effect of thiazides/beta-blockers. The issue, of obvious clinical
importance, can only be solved by placebo-controlled studies, but
placebo-controlled studies are ethically difficult to be conducted nowadays when
evidence favouring active treatment of hypertension and cardiovascular risk is
overwhelming.
Nonetheless, data from a small number of placebo-controlled studies are available.
The diuretic chlorthalidone, often associated with a beta-blocker, has been
compared with placebo in elderly patients with isolated systolic hypertension in
the Systolic Hypertension in the Elderly Program (SHEP) trial: when the current
definition of diabetes was used (fasting glucose, FG, >=126 mg/dl), a significant
higher incidence of diabetes was found in the actively treated group (13 vs 8. 7%,
p<0. 0001) (5), a finding which substantiates the hypothesis that diuretic and
beta-blocker therapy exaggerates the trend towards developing diabetes, i. e. has a
diabetogenic effect. Placebo-controlled studies are also available concerning the
effects of ACEIs and ARBs on diabetes onset. Unfortunately, in all these trials
placebo groups were contaminated by administration of multiple therapies required
for the control of the cardiovascular pathologies of the patients under study. In
the Study on Cognition and Prognosis in the Elderly (SCOPE), concerning elderly
patients with hypertension, the use of hydrochlothiazide and beta-blockers was
more extensive in the so called "placebo" arm than in the active (candesartan)
treatment arm, and may explain the higher incidence of diabetes in the placebo
than the candesartan group (6). Likewise, in four large trials in which an ACEI or
ARB were compared to placebo in patients at high cardiovascular risk because of
coronary heart disease or heart failure, both the ACEI or the ARB and the placebo
were given on top of multiple background therapies required by the severity of the
diseases being investigated. Furthermore, little information is available from
publications of these trials as to what extent background therapies were modified
during the trials and whether these changes were balanced between the placebo and
active treatment arms of the trials (see 3). Therefore the issue whether ACEIs and
ARBs have an active antidiabetogenic action or simply lack the diabetogenic action
of thiazides and beta-blockers remains undecided, and any claim that agents
blocking the renin-angiotensin system exert an antidiabetogenic action appears
unjustified. Prevention of the onset of diabetes, as well as of hypertension, and
even more of the ominous association of diabetes and hypertension, remains,
however, of primary public health concern, because of the morbidity burden
represented by these ailments and the health care cost involved. Prevention must
obviously be exerted before a disease develops, and is most effective in those
subjects in whom the risk of developing the disease is high. Conditions
predisposing to both hypertension and diabetes are well known. Individuals with
so-called high-normal blood pressure (i. e., systolic blood pressure, SBP,
130-139,or diastolic blood pressure, DBP, 85-89 mmHg) have a 40% chance of
becoming hypertensives (i. e.,SBP>=140 or DBP>=90 mmHg) over 4 years according to
the Framingham Heart Study (7)and the initial findings of the Trial Of Preventing
Hypertension (TROPHY, 8). High-normal BP together with impaired glucose tolerance
(as indicated by fasting glucose, FG, >=100 mg/dl), abdominal obesity, a low
HDL-cholesterol and high triglycerides are often found clustered in a large
portion of populations both in USA and Europe, the cluster being commonly referred
to as the metabolic syndrome (MS) (9). Independently of the current debate whether
all manifestations of MS are due to a common pathophysiological mechanism (i. e.,
insulin resistance), it is undisputed that coexistence of high-normal BP, a raised
FG and an elevated BMI is a very strong predictor of both hypertension and
diabetes mellitus.
2. Knowledge effect Lifestyle changes (suitable diet and physical exercise) are known
to be effective in preventing both hypertension (10) and diabetes (10-12), but
whether addition of an ACEI or ARB may further reduce both conditions is unknown.
Individuals with MS are ideal subjects for investigating whether agents blocking
the renin-angiotensin system exert a real antidiabetogenic effect in addition to
what can be achieved by non-pharmacologic measures, as there are no compelling
medical indications for treating these subjects with other drugs that may confound
interpretation of the findings. Therefore the PHIDIAS trial plans to study a large
cohort of individuals with high-normal BP, high FG (but below cut-off values of
diabetes) and abdominal obesity, all instructed to lifestyle changes. They will be
randomly and double-blindly assigned to placebo, or an ACEI or an ARB over a
period of approximately 3 years, in order to investigate whether blockade of the
renin-angiotensin system on top of lifestyle advise can further reduce onset of
diabetes, a hypothesis so far based only on animal studies suggesting that some
ARBs may be partial agonists of peroxisome proliferator-activated receptor gamma
(PPAR-gamma) involved in regulating insulin sensitivity (13). Furthermore, the
subject will be followed up for additional 6 months after withdrawal of randomised
medications to investigate whether the preventive actions are enduring and survive
medication.
3. Implication for AIFA and the NHS Both the conduct and the results of PHIDIAS are
expected to have favourable implications both for the Italian Agency for Medicinal
Products (AIFA) and the Italian National Health System (NHS). The conduct of a
trial such as PHIDIAS that is committed to general practitioners and involve
individuals at high risk of cardiovascular disease, will effectively promote
education to healthier lifestyle measures and help prevention of cardiovascular
disease and diabetes. The results of the trial will also have considerable impact
both on AIFA and the NHS: 1) if addition of an ACEI or ARB to lifestyle measures
is shown not to have any further preventive effect on diabetes, the claim of an
antidiabetogenic action of these agents will be disproved, and their use in
diabetes prevention discouraged; 2) if both an ACEI and an ARB are found to
prevent hypertension and/or diabetes, but their effects are not significantly
different or an ACEI is found more effective than an ARB, the use of a generic
ACEI- such as the one to be administered in PHIDIAS- will represent a benefit for
the subjects combined with considerable savings for the NHS; 3) if an ARB is found
to be significantly more effective than an ACEI in preventing diabetes, this will
implicate temporarily increased costs for the NHS, largely compensated on the long
term by the decreased or delayed onset of diabetes and hypertension, as well as
their complications.
4. Differences from other current trials PHIDIAS substantially differs from a few
ongoing trials of diabetes prevention. The Diabetes Reduction Assessment with
Ramipril and Rosiglitazone Medication (DREAM) trial (14-15) and the Nateglinide
and Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR) trial
(16) are only directed to diabetes prevention. Both of them intend to test an ACEI
(DREAM) or an ARB (NAVIGATOR) versus an antidiabetic agent (rosiglitazone in
DREAM, nateglinide in NAVIGATOR ) versus placebo with a factorial design, in
individuals selected primarily on the basis of impaired glucose tolerance, so that
other cardiovascular conditions are not excluded: in DREAM 43% of recruited
subjects are hypertensives and 35% are dyslipidemic, and in NAVIGATOR previous
cardiovascular disease or risk factors are criteria for eligibility. Therefore in
both studies the investigation of the possible antidiabetogenic effect of the ACEI
or ARB is likely to be confounded to some extent by concomitant therapies for
hypertension and cardiovascular disease. Finally the TROPHY trial (8) is only
planned for prevention of hypertension (by the ARB candesartan) and is not
exploring the equally important issue of diabetes prevention by blockade of the
renin-angiotensin system.
2. Objectives of the study
1. Primary objectives. In a group of individuals with high-normal blood pressure (SBP
130-139, or DBP 85-89 mmHg), FG in the high but nondiabetic range (100-125 mg/dl),
and abdominal obesity (abdominal circumference >= 102 cm in men and >= 88 cm in
women), i. e. with those characteristics of the so called MS that are major
predictors of DM and HT, the trial will explore whether addition of an agent
blocking the renin-angiotensin system (either an ACEI or an ARB) over periodically
reinforced instructions for suitable lifestyle changes reduces: 1) onset of
diabetes (defined as FG >= 126 mg/dl or need for antidiabetic therapy) or 2) onset
of hypertension (defined as SBP >= 140 or DBP >= 90 mmHg, or need for
antihypertensive therapy) to a significantly greater extent than addition of a
placebo.
2. Secondary objectives. In the same group of individuals, the trial will also
investigate whether 1) the diabetes preventing effects of an ACEI and ARB
significantly differ, because of the different blocking mechanisms on the
renin-angiotensin system, and the additional action on bradykinin and,
respectively, on PPAR gamma of the two agents, 2) the effects of the ACEI and ARB
on the onset of diabetes and hypertension are enduring, persisting 3 to 6 months
after substitution of the active drugs with placebo. Obviously, preventive effects
substantially surviving medication would strengthen the therapeutic role of these
agents, whereas disappearance of the effects after a short period would suggest a
masking effect only.
3. Study design
1. Study population
1. Inclusion criteria:
. Men or women of any racial background
- Age >= 40 years and <= 75 years
- SBP>= 130 mmHg and < 140 mmHg or DBP >= 85 mmHg and < 90 mmHg, average
of screening and randomisation visits (in absence of any
antihypertensive medication)
- FG >=100 mg/dl (5. 6 mmol/l) and < 126 mg/dl (7. 0 mmol/l) between
screening and randomisation (in absence of any antidiabetic medication)
- Waist circumference >= 102 cm in men and >= 88 cm in women.
2. Exclusion criteria (see below).
2. Enrolment procedures. The study subjects will be enrolled by general practitioners
associated with the Italian Society of General Practitioners (SIMG). Candidates
for enrolment will be identified by the participating physicians among subjects in
their NHS list attending their clinics. Each physician will be asked to enrol and
randomise 21 subjects within 1 year.
3. Trial design.
- Type of the study. This is a prospective, Italian, multicentre, double-blind,
randomised, placebo-controlled, 3-arm, parallel group comparison with a
response dependent on fixed-dose interventions.
- Interventions. At the randomisation visit, as well as at follow-up visits, at
6-month intervals, all subjects will receive written detailed instruction for
an adequate diet and physical exercise, with the goal of a body weight
reduction of at least 5% (see Annex 1).
In addition to lifestyle advise, all subjects will be randomised to one of the
three following blinded treatments:
1. Placebo : 1 Enalapril placebo tablet and 1 Losartan placebo tablet, once
daily.
2. ACEI : 1 Enalapril tablet and 1 Losartan placebo tablet, once daily.
3. ARB : 1 Losartan tablet and 1 Enalapril placebo tablet, once daily. During
the first four weeks, 10 mg Enalapril tablets and 50 mg Losartan tablets will
be used, and 20 mg Enalapril and 100 mg Losartan tablets will be used for the
rest of the treatment phase of the study. At the end of this phase, all
subjects will receive the two placebo tablets daily for six months
(withdrawal phase).
Among the ACEIs enalapril has been chosen as it has been the most widely
prescribed ACEI for about 20 years, is presently available as a generic agent, and
is one of the ACEIs for which a lower incidence of diabetes has been shown (SOLVD
trial [17]).
Among ARBs losartan may be chosen as animal studies indicates it may be a partial
antagonist of PPAR-gamma to a greater extent than other ARBs (18).
The detailed flow-chart of the study is in Annex 2.
4. Subject allocation. At the time of random allocation to double blind treatment an
individual number will be allocated to each individual subject and noted in the
clinical record form (CRF). The individual number determines which of the three
treatment schemes the individual will receive throughout the treatment period of
the study. By a computer-generated randomisation list prepared by the
randomisation centre using appropriate blocks each subject will be assigned to
one of the three treatment groups with identical probability. The individual
numbers given to each participating physician will be assigned to an individual
subject in ascending order.
5. Outcomes - Primary outcomes. Time to first event of:
1) New diabetes, defined as occurrence of a FG>= 126 mg/dl at any six-month visit
during the treatment phase, to be confirmed at a subsequent visit within one
month; or initiation of any antidiabetic treatment during the treatment period of
the trial.
2) New hypertension, defined as occurrence of a SBP>= 140 mmHg or of a DBP>= 90
mmHg at any six-month visit during the treatment phase, to be confirmed at a
subsequent visit within one month; or initiation of any antihypertensive treatment
during the treatment period of the trial.
- Secondary outcomes. Time to first event (during the treatment phase) of:
1. New diabetes (as defined above) or new hypertension (as defined above), which
comes first.
2. Major cardiovascular events (myocardial infarction, stroke, cardiovascular
death, heart failure, new documented angina, revascularization procedures )
plus death by non-cardiovascular causes.
3. Variations of SBP and DBP during the treatment phase and, separately, during
the withdrawal phase.
4. Variations fasting blood glucose during the treatment phase and, separately,
during the withdrawal phase.
5. Estimated creatinine clearance (Cockroft and Gault formula) lower than 60
ml/min in subjects with values >= 60 ml/min at baseline.
6. Serious adverse effects.
Incidence at the end of the final 6-month withdrawal phase of:
1) New diabetes (as defined above). 2) New hypertension (as defined above)[in
order to test the possibility of a "masking" effect of treatment].
3) Variations of SBP and DBP. 4) Variations of fasting blood glucose.
6. Information retrieval.
- Forms. All relevant information will be filled up in CRFs for the screening
and randomisation visits and all subsequent visits. When required additional
documentation will be attached to the related clinical form.
- Physical examination. See Annex 3.
7. Blood pressure measurement. See Annex 4.
8. Clinical laboratory measurements. See Annex 5.
9. Clinical Outcomes. See Annex 6.
l. Checking of bias and confounding. Compliance to randomised treatment will be checked
at each visit by counting return capsules, but even noncompliant individuals, as well
as individuals withdrawn from medication, will be kept in the trial. Careful search
will be made at each visit of concomitant medication used intermittently or
continuously.
m. Follow up. As illustrated in Fig. 1 (Annex 2), follow-up visits will occur every 6
months (± 1). The trial (see Sample size calculation) will be event-driven, but it is
expected that the treatment phase will be of approximately 3 years.
n. Subjects lost to follow up The subjects being all in the NHS list of the
participating physicians, it is expected that loss to follow up will be minimal
(probably less than 5%), and will consist only of those subjects withdrawing their
consent to participate in the study (and not only to take randomised medication).
o. Monitoring of the study Monitoring of the entire study, committees, centres, and
participating practitioners will be the responsibility of the coordinating institution,
under the supervision of the Principal investigator. Monitoring of participating units
will be done electronically on a continuous way, with the support of a professional
agency.
p. Sample size estimates The primary hypothesis is that incidence of diabetes and,
separately, hypertension will be reduced by active treatment (cumulative data of
enalapril and losartan-treated groups) by 25% with respect to placebo treatment. For
evaluating this difference between the placebo group and the two actively treated
groups together, a two-tailed type I error of 5% and a power of 90% will be accepted.
The main secondary hypothesis is that either of the two active treatments (enalapril
versus losartan) will reduce incidence of diabetes by 25-30% more than the other, with
a two-tailed type I error of 5% and a power of 70-90%. On the basis of the Framingham
Heart Study data in high-normal BP subjects (7) and on initial findings of TROPHY (8),
incidence of hypertension in our study population can be expected to be close to 10%
per year. Assessment of the expected incidence of diabetes is more difficult because of
variable data provided by previous studies. In the hypertension trials that have
suggested a possible antidiabetogenic action of ACEIs and ARBs, annual incidence of
diabetes was between 1. 2 and 4% (3), but those trials that have also explored
predictors of new diabetes suggest higher annual incidences in subjects at higher risk
of diabetes, as follows: 2. 6% in ELSA, patients with metabolic syndrome (19), 2. 7% in
CAPPP, upper risk tertile (20), 3. 4% in LIFE, upper risk quartile (21), and 2. 7% and
7. 2% in VALUE, third and fourth risk quartile (22) 6. 2% in DREAM (15). Three recent
trials investigating interventions to prevent diabetes in subjects with impaired
glucose tolerance (presumably rather similar to those in PHIDIAS, as a multivariable
definition of risk such has ours has been shown to outperform a glucose tolerance test
in predicting onset of diabetes report yearly incidences of diabetes of 7. 5% (23), 11%
(23) and 12. 7% (24), reduced to 3. 7-4. 8% by intense lifestyle counselling. Finally, the
DREAM study (15) is based on the hypothesis that patients with impaired glucose
tolerance have a diabetes annual accrue rate of 4. 5%. On the basis of this evidence, we
have chosen a conservative hypothesis of an yearly accrue rate of diabetes of 3. 5%,
i. e. an incidence of 10. 5% in 3 years. This being a lower incidence rate than that
expected for hypertension, the sample size has been calculated on the diabetes rate. It
has been assumed that, supposing a 4. 8% loss to follow-up, a placebo-treated group of
2000 subjects will develop 200 cases of diabetes in three years, and the two actively
treated groups, of 2000 subjects each, will develop altogether 300 cases of diabetes.
These numbers will provide the required alpha of 5% and power of 90% to detect 25%
reduction of diabetes incidence in the two active treatment groups together (7. 5% in 3
years) compared to the placebo group (10% in 3 years). As to the secondary hypothesis,
2000 subjects in each of the enalapril or losartan groups will be sufficient to detect
a lower incidence of 25% in one group (6. 4% incidence in 3 years) versus the other
(8. 5%) (alpha 5%, power 72%) or a lower incidence of 30% (6. 2 versus 8. 8 in 3 years)
(alpha 5%, power 88%), again supposing a 4. 8% loss to follow-up. In any case the study
will be event driven, and continued until 500 cases of diabetes are observed.
q. Organisation PHIDIAS will be governed by a Steering Committee, chaired by the
Principal Investigator (A. Zanchetti) and formed by 7 other members (G. Mancia, B.
Trimarco, M. Volpe, E. Agabiti Rosei, C. Cricelli, A. Filippi, G. Corrao). A Data
Monitoring and Safety Committee, chaired by L. Berrino and formed by G. Corrao, and E.
Ambrosioni, will monitor the study and review two interim analyses (180 and 360
accumulated cases of diabetes) using previously agreed conservative warning rules for
efficacy and harm. An Operating Committee (A. ZAnchetti, M. Valentini, F. Gregorini, A.
Filippi, E. Romagnoli)will supervise the daily management of the trial. An Endpoint
Committee will provide an independent and blinded assessment of efficacy endpoints (G.
Mancia, M. Volpe). Participating Units will be general medicine physicians associated
with SIMG. The Italian Society of Hypertension (SIIA) in accordance with SIMG will
identify a number of hospital hypertension centres located in areas close to the
participating units, able to provide consulting assistance to the participating
physicians, and yearly sessions of lifestyle counselling for the enrolled subjects. A
Monitoring Unit will be established at the coordinating institution, liaising with a
professional agency (Yghea, Bologna, Italy). A Statistical Unit will also be located at
the coordinating institution under the supervision of G. Corrao, with the
responsibility of randomising treatments, collecting data and analysing them at trial
end. No centralized laboratory is considered nor structured lifestyle support, nor oral
glucose tolerance tests for diagnosis of diabetes, as the trial intends to reproduce,
as far as possible, the conditions under which the NHS can operate.
r. Feasibility The Principal Investigator, Alberto Zanchetti, has a long and extensive
experience in running trials of antihypertensive treatment and treatment of
atherosclerosis (see curriculum vitae). As Scientific Director of the Coordinating
Institution, he confirms that Istituto Auxologico Italiano, IRCCS, accepts to conduct
the study and agrees for the use of the human and technological resources described in
the study protocol.
s. Timing The trial is expected to start about 6 months after eventual AIFA approval.
Recruitment of subjects is expected to be completed in one year. The treatment phase,
although its duration is event-driven, is expected to last an average of 3 years,
followed by a controlled withdrawal phase of 6 months. Predefined check points for
recruitment are at 6, 9, 12 months from study start. Interim analyses from the DMSC are
also considered (see above). A final report is expected within 1 year from study end.
t. Statistical analyses Data analysis will proceed according to CONSORT guidelines for
randomised controlled trials and to the intention-to-treat principle. Analysis are
detailed in Annex 7. In brief, there will be summary statistics on baseline variables,
while primary and secondary efficacy variables will be analysed as time to onset of
diabetes or hypertension, using a Cox regression model adjusted for selected number of
variables.
u. Ethical aspects. The trial is not expected to have potential risks for study
subjects. They have clinical characteristics for which no drug treatment is currently
indicated, and all of them will benefit by receiving detailed healthy lifestyle
counselling. The subjects will receive full written information on the study, and sign
an informed consent document. Approval has been obtained from the Ethical Review
Committee of the Coordinating Institution and will be obtained from those of the NHS
units from which the participating physicians depend.
4. Annex
1. Annex 1. Lifestyle Interventions. At the randomising visit, all subjects will
receive written detailed instructions for adequate diet and physical exercise,
with the goal of a body weight reduction of at least 5%, as follows: diet: total
fat intake of less than 5% of energy consumed, saturated fat to less than 10% of
energy consumed, frequent intake of vegetables, fruit, olive oil (see ref. 8);
exercise: moderate exercise, such as walking, jogging, swimming for 30 min at
least 5 days a week Instructions will be reiterated at each 6-month visit, when
adherence to lifestyle measures and their results will be checked and annotated
in the clinical form. Recruited subjects will also be offered the possibility of
an annual teaching session on healthy lifestyle provided by a hospital
hypertension centre located in the vicinity
2. Annex 2. Study Flow-Chart
Notes:
1. The randomised treatment phase may be prolonged or shortened (and the withdrawal phase
delayed or anticipated) according to the accrual time for the primary outcome diabetes (500
cases) 2. Each time a BP or diabetes outcome is measured, an additional confirmatory visit
should be scheduled within one month 3. In individual cases, additional visits may be
scheduled at the physician's discretion 4. The randomised treatment doses are fixed for all
subjects. However in individual cases, the physician may decide to withdraw medication
(possibly temporarily, followed by rechallenge) but the subject should be maintained in the
trial to preserve intention to treatment.
c. Annex 3. Physical examination. For all physical examinations attention should be focused
on cardiovascular signs and symptoms. The initial physical examination (screening visit) and
the final one comprise the examination of the head, thorax, abdomen, spinal column,
auscultation of the heart and lungs, inspection of the skin, and measurement of bodyweight
and body height, and measurement of waist circumference. To measure waist circumference,
locate top of right iliac crest and place a measuring tape in a horizontal plane around the
abdomen at the level of the iliac crest. Measure at the end of a normal expiration. At
follow-up visits, physical examination comprises a short check of all organ systems
including auscultation of the heart and lungs, and a check for signs and symptoms of
cardiovascular diseases. Waist circumference and body weight must be measured at all
follow-up visits. Data will be recorded in specific boxes on Clinical Report Forms
d. Annex 4. Blood pressure measurement. Using a calibrated standard sphygmomanometer or a
validated digital device and appropriate size cuff, blood pressure will be measured with the
subjects' arm supported at heart level. Systolic and diastolic blood pressure will be
recorded by the investigator at phase I and V of Korotkoff sounds, or as indicated by the
digital device. The cuff should be deflated at a rate not greater than 2 mmHg/sec with the
patient sitting quietly for several minutes. Blood pressure will be measured 3 times at 1
min intervals. Blood pressure will be measured in all subjects at the screening and
randomization visits, and during all follow-up visits at 6-month intervals. If a value of
SBP>= 140 or DBP>=90 mmHg (cut-offs for hypertension) is measured at a follow-up visit, this
should be confirmed during a second visit within one month. If the participating physician
decides for antihypertensive treatment, the use of a calcium antagonist is less likely to
interfere in either way with development of diabetes.
e. Annex 5. Clinical laboratory. Haematology: haemoglobin, haematocrit, red blood cell
count, white blood cell count, platelet count will be measured before randomization and
study end. Biochemistry: fasting glucose will be measured before randomization and at all
follow-up visits at 6-month intervals Fasting triglycerides, total cholesterol, HDL-
cholesterol, creatinine, potassium, AST (SGOT), ALT (SGPT), as well as proteinuria (dip
stick) will be measured before randomization and subsequently at yearly intervals.
f. Annex 6. Clinical outcomes. Death and the cause of death will be documented in the
clinical report form of the first visit missed by a deceased individual. Non fatal
cardiovascular and renal events will be documented by careful inquiry with the subject and
family members, and every effort will be made to obtain hospital or similar documentation
when available.
g. Annex 7. Statistical analysis. Data analysis will be performed according to CONSORT
guidelines for randomised controlled trials and to the intention-to-treat principle.
1. Comparability between groups Summary statistics on demographic and clinical baseline
variables will be calculated by treatment group, and comparisons between treatment
groups will be performed. Analysis of variance models or nonparametric tests will be
utilized for continuous variables, whereas Mantel-Haenszel, Cochran-Mantel-Haenszel,
chi-square or Fisher's exact tests will be performed for between-group comparison of
categorical variables, as indicated.
2. Analysis of primary efficacy variables The time-to-event primary efficacy variables
(time to onset of diabetes and time to onset of hypertension, during the treatment
phase of the trial) will be analysed separately for diabetes and hypertension, using a
Cox regression model including treatment (placebo vs treatment), and the following
baseline covariates: age, gender, race, BMI, FG, SBP, DBP. Subgroup analyses will be
performed based at least on the following criteria: age groups, gender, BMI and FG
groups (above and below medians), SBP and DBP (above and below medians). The assumption
of proportional hazards will be checked for using graphic methods, and a secondary
analysis of sensitivity will be performed utilizing the log-rank test.
3. Analyses of secondary efficacy variables Secondary variables for which time-to-event
can be defined will be analysed using the same models as for the primary variable. For
the secondary efficacy variables for which time-to-event cannot properly be calculated
(incidence of diabetes and hypertension at the end of the final 6-month withdrawal
phase), logistic regression models will be utilized adjusting for factors as for
primary variable analysis.
Eligibility
Minimum age: 40 Years.
Maximum age: 75 Years.
Gender(s): Both.
Criteria:
Inclusion Criteria:
- Men or women of any racial background
- Age >= 40 years and <= 75 years
- SBP>= 130 mmHg and < 140 mmHg or DBP >= 85 mmHg and < 90 mmHg, average of screening
and randomisation visits (in absence of any antihypertensive medication)
- FG >=100 mg/dl (5. 6 mmol/l) and < 126 mg/dl (7. 0 mmol/l) between screening and
randomisation (in absence of any antidiabetic medication)
- Waist circumference >= 102 cm in men and >= 88 cm in women.
Exclusion Criteria:
- SBP >= 140 mmHg or DBP >= 90 mmHg
- Any antihypertensive, antidiabetic or antiobesity medication at the time of or during
the 6 months previous to randomisation
- Any current or previous cardiovascular or renal disease requiring continuous
administration of Ds, ßBs, ACEIs, ARBs, CAs, and any other antihypertensive
medication
- Any medical condition preventing adherence to lifestyle measures included in the
protocol
- Hepatic disease as AST (SGOT) or ALT (SGPT) values equal or greater than two times
the upper limit of normal
- Chronic renal dysfunction as serum creatinine > 2. 0 mg/dl
- Any gastrointestinal disorder interfering with drug absorption
- Known allergy or contraindications to ACEIs or ARBs
- Pregnant or lactating women; women in reproductive age not using recognized
contraceptive methods
- Malignancy within the last 5 years
- Clinically significant autoimmune disorders
- Drug abuse or alcohol abuse within the last 5 years
- History of noncompliance to medical regimens
- Incapacity or unwillingness to sign the informed consent
- Participation in any investigational clinical trial within the last 3 months
Locations and Contacts
Alberto Zanchetti, MD, Phone: + 3902619112894, Email: alberto.zanchetti@unimi.it
Istituto Auxologico Italiano., Milan 20145, Italy
Additional Information
Related publications: Zanchetti A, Ruilope LM. Antihypertensive treatment in patients with type-2 diabetes mellitus: what guidance from recent controlled randomized trials? J Hypertens. 2002 Nov;20(11):2099-110. Review. Turnbull F, Neal B, Algert C, Chalmers J, Chapman N, Cutler J, Woodward M, MacMahon S; Blood Pressure Lowering Treatment Trialists' Collaboration. Effects of different blood pressure-lowering regimens on major cardiovascular events in individuals with and without diabetes mellitus: results of prospectively designed overviews of randomized trials. Arch Intern Med. 2005 Jun 27;165(12):1410-9. Mancia G, Grassi G, Zanchetti A. New-onset diabetes and antihypertensive drugs. J Hypertens. 2006 Jan;24(1):3-10. Review. Elliott WJ, Meyer PM. Incident diabetes in clinical trials of antihypertensive drugs: a network meta-analysis. Lancet. 2007 Jan 20;369(9557):201-7. Kostis JB, Wilson AC, Freudenberger RS, Cosgrove NM, Pressel SL, Davis BR; for the SHEP Collaborative Research Group. Long-term effect of diuretic-based therapy on fatal outcomes in subjects with isolated systolic hypertension with and without diabetes. Am J Cardiol. 2005 Jan 1;95(1):29-35. Lithell H, Hansson L, Skoog I, Elmfeldt D, Hofman A, Olofsson B, Trenkwalder P, Zanchetti A; SCOPE Study Group. The Study on Cognition and Prognosis in the Elderly (SCOPE): principal results of a randomized double-blind intervention trial. J Hypertens. 2003 May;21(5):875-86. Vasan RS, Larson MG, Leip EP, Kannel WB, Levy D. Assessment of frequency of progression to hypertension in non-hypertensive participants in the Framingham Heart Study: a cohort study. Lancet. 2001 Nov 17;358(9294):1682-6. Julius S, Nesbitt S, Egan B, Kaciroti N, Schork MA, Grozinski M, Michelson E; TROPHY study group. Trial of preventing hypertension: design and 2-year progress report. Hypertension. 2004 Aug;44(2):146-51. Epub 2004 Jul 6. National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) final report. Circulation. 2002 Dec 17;106(25):3143-421. No abstract available. European Society of Hypertension-European Society of Cardiology Guidelines Committee. 2003 European Society of Hypertension-European Society of Cardiology guidelines for the management of arterial hypertension. J Hypertens. 2003 Jun;21(6):1011-53. No abstract available. Erratum in: J Hypertens. 2003 Nov;21(11):2203-4. J Hypertens. 2994 Feb;22(2):435. Tuomilehto J, Lindstrom J, Eriksson JG, Valle TT, Hamalainen H, Ilanne-Parikka P, Keinanen-Kiukaanniemi S, Laakso M, Louheranta A, Rastas M, Salminen V, Uusitupa M; Finnish Diabetes Prevention Study Group. Prevention of type 2 diabetes mellitus by changes in lifestyle among subjects with impaired glucose tolerance. N Engl J Med. 2001 May 3;344(18):1343-50. Knowler WC, Barrett-Connor E, Fowler SE, Hamman RF, Lachin JM, Walker EA, Nathan DM; Diabetes Prevention Program Research Group. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002 Feb 7;346(6):393-403. Kurtz TW, Pravenec M. Antidiabetic mechanisms of angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists: beyond the renin-angiotensin system. J Hypertens. 2004 Dec;22(12):2253-61. Review. DREAM (Diabetes REduction Assessment with ramipril and rosiglitazone Medication) Trial Investigators; Gerstein HC, Yusuf S, Bosch J, Pogue J, Sheridan P, Dinccag N, Hanefeld M, Hoogwerf B, Laakso M, Mohan V, Shaw J, Zinman B, Holman RR. Effect of rosiglitazone on the frequency of diabetes in patients with impaired glucose tolerance or impaired fasting glucose: a randomised controlled trial. Lancet. 2006 Sep 23;368(9541):1096-105. DREAM Trial Investigators; Bosch J, Yusuf S, Gerstein HC, Pogue J, Sheridan P, Dagenais G, Diaz R, Avezum A, Lanas F, Probstfield J, Fodor G, Holman RR. Effect of ramipril on the incidence of diabetes. N Engl J Med. 2006 Oct 12;355(15):1551-62. Epub 2006 Sep 15. Deedwania PC, Schmieder R. Angiotensin receptor blockers: Cardiovascular protection in the metabolic syndrome. J Renin Angiotensin Aldosterone Syst. 2006 Jun;7 Suppl 1:S12-8. Review. Vermes E, Ducharme A, Bourassa MG, Lessard M, White M, Tardif JC; Studies Of Left Ventricular Dysfunction. Enalapril reduces the incidence of diabetes in patients with chronic heart failure: insight from the Studies Of Left Ventricular Dysfunction (SOLVD). Circulation. 2003 Mar 11;107(9):1291-6. Schupp M, Lee LD, Frost N, Umbreen S, Schmidt B, Unger T, Kintscher U. Regulation of peroxisome proliferator-activated receptor gamma activity by losartan metabolites. Hypertension. 2006 Mar;47(3):586-9. Epub 2005 Dec 19. Cuspidi C, Meani S, Valerio C, Sala C, Fusi V, Zanchetti A, Mancia G. Age and target organ damage in essential hypertension: role of the metabolic syndrome. Am J Hypertens. 2007 Mar;20(3):296-303. Niklason A, Hedner T, Niskanen L, Lanke J; Captopril Prevention Project Study Group. Development of diabetes is retarded by ACE inhibition in hypertensive patients--a subanalysis of the Captopril Prevention Project (CAPPP). J Hypertens. 2004 Mar;22(3):645-52. Lindholm LH, Ibsen H, Borch-Johnsen K, Olsen MH, Wachtell K, Dahlof B, Devereux RB, Beevers G, de Faire U, Fyhrquist F, Julius S, Kjeldsen SE, Kristianson K, Lederballe-Pedersen O, Nieminen MS, Omvik P, Oparil S, Wedel H, Aurup P, Edelman JM, Snapinn S; For the LIFE study group. Risk of new-onset diabetes in the Losartan Intervention For Endpoint reduction in hypertension study. J Hypertens. 2002 Sep;20(9):1879-86. Kjeldsen SE, Julius S, Mancia G, McInnes GT, Hua T, Weber MA, Coca A, Ekman S, Girerd X, Jamerson K, Larochelle P, MacDonald TM, Schmieder RE, Schork MA, Stolt P, Viskoper R, Widimsky J, Zanchetti A; VALUE Trial Investigators. Effects of valsartan compared to amlodipine on preventing type 2 diabetes in high-risk hypertensive patients: the VALUE trial. J Hypertens. 2006 Jul;24(7):1405-12. Chiasson JL, Josse RG, Gomis R, Hanefeld M, Karasik A, Laakso M; STOP-NIDDM Trail Research Group. Acarbose for prevention of type 2 diabetes mellitus: the STOP-NIDDM randomised trial. Lancet. 2002 Jun 15;359(9323):2072-7.
Starting date: September 2007
Ending date: September 2012
Last updated: April 4, 2007
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