Diabetes Mellitus Type 2
Conditions
Keywords
Type 2 diabetes, Obstructive sleep apnea, Glycemic control, Insulin resistance, Sleep disordered breathing
Brief summary
Obstructive Sleep Apnea (OSA) and type 2 diabetes mellitus are two prevalent medical conditions with significant associated cardiovascular and cerebrovascular morbidity and mortality. Research indicates that the prevalence of OSA is increased in diabetic patients when compared with normoglycemic patients and that OSA is independently associated with type 2 diabetes. Further research suggests that effective treatment of the OSA with continuous positive airway pressure (CPAP) improves insulin responsiveness in both non-diabetic OSA patients and diabetic-OSA patients. We are proposing a clinical trial to evaluate the impact of 6 months of CPAP therapy on glycemic control in type 2 diabetic patients with OSA. The primary objective of this study is to assess the effectiveness of CPAP in improving glycemic control (HbA1c) in type 2 diabetic patients with newly diagnosed OSA. Secondary objectives of this study include: assessment of fasting and post prandial glucose, determination as to whether there are any biochemical markers for OSA in the type 2 diabetic population; assessment of any improvements in cardiovascular outcomes; evaluation of any improvement in quality of life. Patients with OSA will be randomized into one of two groups: either a CPAP treatment group or a non-treatment group. Patients will be followed at 3 months and 6 months with collection of various lab tests to assess glycemic control.
Detailed description
Patients attending clinical sites involved with the trial will be asked to participate in the study. Patients will undergo a sleep test and if positive for Obstructive Sleep Apnea (OSA) will continue in the study. At the time of enrolment baseline history and physical examination will be assessed. Baseline lab samples will also be obtained to measure levels of fasting blood glucose, insulin, HbA1c, lipids, biochemical markers and creatinine/albumin ratio. Post-prandial glucose levels and 24-hour ambulatory blood pressure will be evaluated. Participants will also be asked to complete Quality of Life (QoL) questionnaires. Participants will be randomised into either continuous positive airway pressure CPAP treatment or no treatment. All subjects will be counselled regarding adopting a healthy lifestyle and advised on the Heart Foundation, National Health and Medical Research Council, and American Diabetes Association nutrition and exercise recommendations. Follow-up on adoption of the healthy lifestyle approach will be done for all study participants for the duration of the trial period. Total duration of a patient's participation is 6 months.
Interventions
Positive Airway Pressure (PAP) therapy initiated at Randomization and continued through the entire study duration (6 months), with instructions for use on a daily basis, during periods of sleep.
BEHAVIORALLifestyle counseling
Lifestyle counseling: All subjects were counseled regarding adopting a healthy lifestyle and advised on the Heart Foundation, National Health and Medical Research Council, and American Diabetes Association nutrition and exercise recommendations.
Sponsors
Royal North Shore Hospital
Baker Heart and Diabetes Institute
International Diabetes Center at Park Nicollet
ResMed
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. 18 years of age or older, 2. Known diagnosis of type 2 diabetes for at least 3 months 3. HbA1c \>6.5% and \</= 8.5% 4. BMI \</= 40 kg/m2
Exclusion criteria
1. Requires oxygen therapy 2. OSA is severe (AHI\>70 or SaO2\<70%) 3. Work in transport related industries 4. Previous diagnosis of OSA 5. Known MVA due to sleepiness in the previous 5 years 6. Insulin-requiring 7. Use of GLP-1 mimetic (e.g. Byetta) for \< 6 months or \> 6 months but weight not stable 8. Unstable angina
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| HbA1c Change | Baseline to Month 6 | Month 6 change in HbA1c (%) |
Countries
Australia, Canada, United States
Participant flow
Recruitment details
Subjects for this study were recruited from 15 medical clinics located in the United States and Australia.
Pre-assignment details
Subjects were presented with an Informed Consent Form (and HIPAA in USA) and assessed for eligibility based on inclusion /exclusion criteria. If all IEC met, subjects randomized 1:1. 118 subjects not included in endpoint analysis due to reanalysis of Obstructive Sleep Apnea (OSA) inclusion criteria. 298 of the 416 were included for final analysis.
Participants by arm
| Arm | Count |
|---|---|
| Lifestyle Counseling With PAP Therapy | 151 |
| Lifestyle Counseling | 147 |
| Total | 298 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 1 | 1 |
| Overall Study | Did not meet revised inclusion criteria | 56 | 62 |
| Overall Study | Including: subject change of address | 5 | 2 |
| Overall Study | Lost to Follow-up | 1 | 1 |
| Overall Study | Withdrawal by Subject | 25 | 6 |
Baseline characteristics
| Characteristic | Lifestyle Counseling With PAP Therapy | Lifestyle Counseling | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 67 Participants | 57 Participants | 124 Participants |
| Age, Categorical Between 18 and 65 years | 84 Participants | 90 Participants | 174 Participants |
| Age, Continuous | 62.4 years STANDARD_DEVIATION 9.1 | 62.1 years STANDARD_DEVIATION 9 | 62.3 years STANDARD_DEVIATION 9 |
| Region of Enrollment Australia | 97 participants | 88 participants | 185 participants |
| Region of Enrollment United States | 54 participants | 59 participants | 113 participants |
| Sex: Female, Male Female | 52 Participants | 54 Participants | 106 Participants |
| Sex: Female, Male Male | 99 Participants | 93 Participants | 192 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 78 / 147 | 94 / 151 |
| serious Total, serious adverse events | 5 / 147 | 10 / 151 |
Outcome results
Primary
HbA1c Change
Month 6 change in HbA1c (%)
Time frame: Baseline to Month 6
Population: The following definition was applied to the primary endpoint: included in analysis were all participants that had at least 1 follow-up HbA1c value in addition to the Baseline HbA1c were considered.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Lifestyle Counseling With PAP Therapy | HbA1c Change | -0.1 HbA1c percent | Standard Deviation 0.8 |
| Lifestyle Counseling | HbA1c Change | -0.1 HbA1c percent | Standard Deviation 0.7 |