Exercise Training in Older Diabetic Women
Condition: Cardiovascular Diseases; Diabetes Mellitus, Type 2
MeSH terms: Cardiovascular Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 2
Study type: Interventional
Phase: Phase 1

Summary: 
      Type 2 diabetics (non-insulin-dependent) are more than five times as likely to suffer an
      initial myocardial infarction (MI; heart attack) compared to nondiabetics.Female diabetics in
      particular, have a higher mortality rate for coronary artery disease (CAD) than male
      diabetics.C-reactive protein measurement in the clinical setting enhances the detection of
      individuals who are at high risk for cardiovascular disease (CVD), by providing additional
      predictive value.

      We propose to study the effects of a supervised exercise and diet intervention on
      cardiovascular disease risk in postmenopausal diabetic women. We will recruit 35
      postmenopausal, sedentary type 2 diabetics who will undergo a 3 month exercise and dietary
      intervention. They will exercise 3 times a week for 30 min in a supervised setting. Exercise
      mode will be aerobic and self-selected (i.e. treadmill, bike) at an intensity level of 50-85%
      VO2peak. Blood glucose will be monitored before and after exercise. The dietary intervention
      will consist of 6 meetings with a registered dietitian.

      The study is designed to test the following hypotheses:

        -  Cardiovascular disease risk measures will be different following a 3-month exercise and
           diet intervention.

             -  H1: Blood markers for coronary artery disease risk, as measured by CRP, TC, LDL,
                TG, FG, fasting insulin, and HbA1c, will be different following a 3-month exercise
                and diet intervention.

             -  H2: Anthropometric measures of coronary artery disease risk, as measured by WHR,
                will be different following a 3-month exercise and diet intervention.

             -  H3: Resting blood pressure, as measured by SBP and DBP, will be different following
                a 3-month exercise and diet intervention.

             -  H4: Total body fat, as measured by DXA, will be different following a 3-month
                exercise and diet intervention.

        -  Health-related measures will be different following a 3-month exercise and diet
           intervention.

             -  H1: Cardiorespiratory fitness, as measured by maximal oxygen consumption (VO2max)
                will be different following a 3-month exercise and diet intervention.

             -  H2: Bone-mineral density, as measured by DXA, will be different following a 3-month
                exercise and diet intervention.

             -  H3: Dietary measures (total daily kcal, and daily fat kcal) will be different
                following a 3-month exercise and diet intervention.
    

Detailed description: 
      -  Recruitment: Participants who have signed up for the research recruitment mailing list
           at the UCSF/Mt. Zion Osteoporosis Center will be mailed a CHR approved recruitment
           letter that briefly describes the study purpose and eligibility criteria. Only the
           individual's name and address are on the mailing list; there is no medical information.
           Medical records are not accessed. Telephone screening will take place in the ESS
           Department at USF. A script will be followed.

        -  Pre and Post-Testing: Interested subject candidates will be scheduled to meet with Dr.
           Orri or Dr. Thompson at USF to provide written informed consent and complete a health
           history questionnaire (see appendix) to evaluate their CV risk. They will obtain written
           medical notification from their physician stating that they are in adequate diabetic
           control and cleared to begin an exercise program. Once selected, measurements of HT, WT,
           WHR, SBP, and DBP will take place in the ESS lab at USF.

        -  Blood draws: Subjects will arrive at the UCSF GCRC after a 12-hr fast. The blood
           variables obtained will include: CRP, TC, LDL-C, HDL-C, TG, FG, fasting insulin (HOMA
           calculated for marker of insulin resistance), and HbA1c. Approximately 2 tablespoons of
           blood will be drawn.

        -  Bone mineral density: BMD measurements (dual X-ray absorptiometry, DXA) will take place
           at the General Clinical Research Center at UCSF following the blood draw. A snack will
           be provided to the subjects prior to entering the DXA scanning area.

        -  Cardiorespiratory fitness: Maximal exercise testing will be using a treadmill protocol
           in the Exercise Physiology Laboratory at UCSF General Clinical Research Center. Tests
           will be conducted by Dr. Orri, Dr. Thompson, and Joanne Krasnoff, M.S. The Naughton
           protocol will be used in which the grade is increased 3.5% every 2 min, while the speed
           remains at 2 mph after the warmup. The subject continues until volitional exhaustion or
           the exercise technicians terminate test end as designated by the American College of
           Sports Medicine (ACSM).

      All participants will have a 12-lead electrocardiogram (ECG) during the testing sessions to
      monitor for dysrhythmias or ischemia. Heart rate and blood pressure will be monitored every 2
      minutes. Rating of perceived exertion (RPE) will be assessed every minute of the test.
      Maximal oxygen uptake (VO2max), as well as maximal levels of blood pressure, heart rate,
      respiratory exchange ratio (RER), and RPE will be recorded at the end of the test and used to
      determine the exercise training intensity. Expired gases will be collected throughout the
      test with CO2 and O2 and volume analyzed for calculation of oxygen uptake using a Quinton QMC
      computerized gas analysis system (Quinton Instruments, Bothell WA). All exercise technicians
      will be CPR and first-aid certified.

        -  Body composition and BMD: Per cent body fat (%BF) and BMD will determined using dual
           energy X-ray absorptiometry (DXA). All scans will be done on a GE-Lunar Prodigy
           (Madison, WI). Variables of interest from the DXA scan will be %BF, total fat mass, lean
           body mass (LBM), and bone mineral density in g/cm2.

        -  Exercise intervention: The 3-month exercise intervention will take place at the
           Millberry Union fitness center at UCSF, times per week for 30 min each session,
           accompanied by certified fitness professional who is trained to work with special
           populations. All standard emergency procedures will be followed by the trained UCSF
           staff.

        -  Exercise program design: Study participants will be required to complete 36 exercise
           sessions in the 12 week program. They will exercise a minimum of 3 times per week for 30
           min, accompanied by certified fitness professional who is trained to work with special
           populations. Participants will wear a HR monitor and be instructed to maintain an
           intensity in the range of 50-85% VO2peak obtained through max testing. During the
           initial phase of training (first 4 weeks), participants who are unable to exercise
           continuously for 30 minutes will perform intermittent exercise bouts of 10 minutes
           followed by 5 min of rest. Mode of exercise will be self-selected and will involve large
           muscle groups, incorporating any combination of the following machines: treadmill,
           stationary cycle, elliptical, Stairmaster, or rowing ergometer.

        -  Blood glucose monitoring: Participants will be instructed to consume a snack 30-60 min
           before exercise. Prior to beginning each exercise session, all subjects will monitor
           their blood glucose to verify that it is between 100 and 250 mg/dl, in the absence of
           hypo/hyperglycemic symptoms (6). In addition, subjects will be monitored for 30 min
           post-exercise to verify that their BG is > 70 mg/dl. Juice and protein snacks (peanut
           butter & crackers) will be available to the subjects in case of post-exercise
           hypoglycemia. The exercise supervisor will be aware of those subjects who are taking
           medications that promote insulin production and will carry a glucagon pen. Late-evening
           exercise sessions will be avoided in order to prevent nocturnal hypoglycemia.

        -  Dietary intervention: The subjects will receive six 30-min nutrition group counseling
           sessions with a dietitian. Sessions 1 and 6 will involve instruction on preparing 3-day
           dietary logs, while sessions 2-5 will consist of selected topics (i.e. dietary
           recommendations, low sodium diets, blood glucose control).
    

Intervention name(s): 3-month Exercise Training and Diet Education
Intervention type(s): Behavioral
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Exercise; Diabetes Mellitus, Type 2; Postmenopause; Diet