Step Monitoring to Improve ARTERial Health
Märksõnad
Abstraktne
Kirjeldus
BACKGROUND: High walking levels reduce myocardial infarction, stroke, and mortality rates in overweight/obese patients with diabetes and/or hypertension, but our own work, led by Nominated Principal Applicant K. Dasgupta, indicates low daily step counts in these patients, at approximately 5,000 steps/day on average with a further 15% reduction during fall and winter. A meta-analysis of physical activity programs indicates that pedometer-based monitoring programs can lead to higher daily step counts, but evidence for impact on arterial health is limited, as is evidence for the effectiveness of a pedometer-based strategy specifically implemented into the usual clinical care of patients with diabetes and/or hypertension. The SMARTER trial will address these knowledge gaps.
PRIMARY RESEARCH QUESTION: Among sedentary overweight/obese adults with diabetes and/or hypertension do physician-delivered step count prescriptions integrated into usual care reduce arterial stiffness more than usual care alone, over a one-year period? Arterial stiffness (primary outcome), a summative indicator of arterial health, is more precise and reliable than individual risk factors. An analysis of the Framingham Heart Study demonstrated that, even after adjustment for traditional risk factors, increased arterial stiffness was independently associated with a 48% increase in vascular disease risk. Co-Principal Applicant S. Daskalopoulou is an expert in the noninvasive assessment of arterial stiffness and has a well-equipped Vascular Lab funded through a CFI grant.
STUDY DESIGN: Randomized, allocation concealed, single-blind (outcome assessors), intervention allocation ratio 1:1, multisite clinical trial. This design will allow for the level A evidence necessary to justify widespread change in clinical practice.
TRIAL SYNOPSIS: Given that the majority of diabetes and hypertension patients are managed in primary care settings, the SMARTER trial interventions will be delivered through the large network of primary care clinics accessible to Co-Principal Applicant E. Rosenberg as well as diabetes and internal medicine clinics throughout Montreal where patients may receive their primary diabetes and hypertension follow-up. Twenty-four collaborating physicians have been identified. Physicians/clinic staff will obtain assent from candidates within their practice for contact by the SMARTER coordinator. The number of collaborating physicians continues to be increased, including physicians at primary care, diabetes, hypertension, internal medicine, and endocrinology clinics. Eligibility: Candidates will be adults with 25≤BMI<40 kg/m2 followed for diabetes and/or hypertension and sedentary to somewhat active. Evaluations: Formal trial evaluations, conducted at baseline and 12 months, will include assessments of arterial stiffness (carotid femoral pulse wave velocity measured noninvasively with applanation tonometry); step counts (pedometer with concealed window) and physical activity (accelerometer) worn for one week; fitness (exercise stress test; ˙VO2max); anthropometric parameters; and individual vascular risk factors. Intervention arm: The physician gives the active trial participants a pedometer, log book, and a step count prescription based on the baseline daily step count. The time frame for a > 3,000 steps/day net increase is 10 months for sedentary participants (<5,000 steps/day), 7 months for low active participants (5,000-7,499 steps/day), and 5 months for somewhat active participants (7,500-9,999 steps/day). There will be four clinic visits over one year. Control arm: Same visit frequency with advice to engage in 30-60 minutes of activity on most days of the week. Sample Size: Allowing for a loss to follow-up of up to 17% based on our previous studies, investigators will require a sample size of 364 individuals (i.e. 182 per arm) to detect a 10% difference in change in arterial stiffness between our active and control arms to an accuracy of +/- 5% over a one-year period. Analysis: Intention-to-treat. Between-arm differences in 'after minus before changes' with 95% CIs for main analysis.
Addedum to stress testing: Due to timeline limitations, we were obliged to forego stress testing assessments as of October 20, 2014. This does not impact our primary outcome. Moreover, stress testing is not required when engaging in a walking program in type 2 diabetes. We will be able to assess impacts of the intervention on fitness (secondary outcome) in a subgroup of patients (i.e., those who completed assessments before October 20, 2014).
IMPORTANCE: With increasing numbers of diabetes and hypertension patients, there is a pressing need for effective and efficient clinical practice strategies to help physicians support their patients to achieve the arterial health benefits of higher physical activity levels. The SMARTER trial seeks to provide such a tool. If effectiveness is demonstrated, all efforts will be made for the inclusion of our approach in Clinical Practice Guidelines for diabetes and hypertension, and investigators will develop training tools (manuals, websites, CD-ROMs) to allow maximal uptake of our proposed strategy.
AN OBSERVATIONAL SUBSTUDY: Novel Real-Time Measurement of Physical Activity Patterns in Type 2 Diabetes and Hypertension Through GPS Monitoring and Accelerometry
In addition to the main clinical trial, we are conducting additional measurements among consenting type 2 diabetes patients in order to examine the effects of the walkability of their home neighbourhood on their baseline step count and time at different physical activity intensities (accelerometer measurement already being performed through SMARTER). The additional measurements include wearing a Geographical Positioning Systems (GPS) device for the 7-day period that they wear the pedometer with concealed viewing window and accelerometer. The GPS device collects time-stamped location information such that X,Y coordinates are collected. These are used to determine the times that they are within or outside neighbourhood buffer zones.
For the assessment of neighbourhood walkability,the parameters assessed include population density, pedestrian-friendly design and diversity of destinations - commonly referred to in the urban planning literature as the 3D's. The variables that best capture density, design, and diversity include residential density, street connectivity and land use mix. Residential density is defined as the number of residences per square kilometre of residential land area. Street connectivity is defined as the number of ≥3-way intersections per square kilometre in neighbourhood, where a greater number of intersections facilitates movement between origins (e.g., residences) and destinations (e.g., shops and parks).Land-use mix is a measure of the number of different land uses located within a neighbourhood.Land use mix is assessed via an entropy score - a value between zero and one that captures the degree of heterogeneity of land uses in a neighbourhood. A subcomponent of land use mix that may be a particularly important for encouraging individuals to walk within their neighbourhood and that is easily incorporated into the design of new neighbourhoods is greenspace/recreational land area.
We are using Geographical Information System (GIS) mapping (computer-based assessment of neighbourhood characteristics derived from existing data sources that have some spatially referenced identification, such as a home address) to measure these facets of neighbourhood walkability.In brief, each of the variables will be derived by geocoding participants six-digit home postal codes, constructing 1-kilometre polygonal buffers zones around each participants home address (i.e., a geographical zone around the centroid of the postal code area) and calculating the measures of interest for each neighbourhood using tools within a GIS software package (ArcGIS) and publically available shape files.
Means and standard deviations will be used to describe the number of steps per day occurring specifically in home neighbourhoods (i.e., as determined through GPS) and overall. Multiple linear regression analyses will be used to assess the relationship between 1) home neighbourhood environments and the number of steps taken per day in the home neighbourhood and 2) home neighbourhood environments and the number of steps taken per day taken in any location. These analyses will be repeated with time at moderate to vigorous activity in lieu of steps as the outcome variable. Several variables measured through SMARTER will be considered for exclusion in models (e.g., age, sex, educational level, BMI).
This observational substudy is partly funded by an operating grant from the Heart and Stroke Foundation (Quebec) awarded to K. Dasgupta (Principal Investigator) and Nancy Ross (Co-Principal Investigator on substudy) and is being led by Samantha Hajna, their doctoral candidate student.
Kuupäevad
Viimati kinnitatud: | 02/28/2017 |
Esmalt esitatud: | 11/15/2011 |
Hinnanguline registreerumine on esitatud: | 11/17/2011 |
Esmalt postitatud: | 11/20/2011 |
Viimane värskendus on esitatud: | 03/20/2017 |
Viimati värskendus postitatud: | 03/22/2017 |
Õppe tegelik alguskuupäev: | 01/31/2012 |
Eeldatav esmane lõpetamise kuupäev: | 02/29/2016 |
Eeldatav uuringu lõpetamise kuupäev: | 02/29/2016 |
Seisund või haigus
Sekkumine / ravi
Behavioral: Step Count Prescription Arm
Behavioral: Usual care arm
Faas
Käerühmad
Arm | Sekkumine / ravi |
---|---|
Experimental: Step Count Prescription Arm The active trial arm intervention consists of usual care plus step count prescription delivered by the treating doctor, over a one-year period. | Behavioral: Step Count Prescription Arm Treating physicians will provide a pedometer, pedometer log, and step count prescription. The aim is a net increase of at least 3,000 steps/day over one year. The time frame for this increase will be 10 months for sedentary participants (<5,000 steps/day), 7 months for low active participants (5,000-7,499 steps/day), and 5 months for somewhat active participants (7,500-9,999 steps/day). If goals are not met, the doctor and participant will review barriers and facilitators, and a more individualized prescription will be formulated (e.g. lower incremental step count targets or slower rate of dose escalation). For participants who meet goals, the doctor and participant will together decide whether to aim for a further increase. |
Active Comparator: Usual care arm The control trial arm will receive usual care alone, over a one-year period (i.e. no step count prescription but, in accordance with guidelines, including advice to engage in 30-60 minutes of activity on most days of the week). Consistent with clinical practice guidelines, our collaborating doctors have indicated that the usual care of the target population requires clinic visits at roughly three-month intervals to ensure vascular risk factor monitoring and management. | Behavioral: Usual care arm The control trial arm will receive usual care alone, over a one-year period (i.e. no step count prescription but, in accordance with guidelines, including advice to engage in 30-60 minutes of activity on most days of the week). |
Abikõlblikkuse kriteeriumid
Õppimiseks sobivad vanused | 18 Years To 18 Years |
Uuringuks kõlblikud sood | All |
Võtab vastu tervislikke vabatahtlikke | Jah |
Kriteeriumid | Inclusion Criteria: - Followed by a SMARTER collaborating doctor - BMI ≥ 25 kg/m2 but < 40 kg/m2 (i.e. overweight to class II obese) - Type 2 diabetes and/or hypertension - Conversant in either English or French Exclusion Criteria: - ≥ 150 minutes of leisure time physical activity per week be self- report - Acute or chronic co-morbid conditions that may affect the ability or likelihood to adhere to trial procedures (e.g. inflammatory arthritis, active malignancy, major depression or other significant psychiatric disorders, and/or significant visual impairment) - Pregnancy/planning a pregnancy - Baseline step count averaging ≥ 10,000 steps/day at baseline assessment - Arrhythmia that prevents accurate assessment of carotid-femoral pulse wave velocity (e.g., atrial fibrillation) |
Tulemus
Esmased tulemusnäitajad
1. change in arterial stiffness [one year]
Sekundaarsed tulemusmõõdud
1. change in daily step count [one year]
2. change in physical activity [one year]
3. change in physical fitness [one year]
4. weight change from baseline [one year]
5. body mass index change from baseline [one year]
6. change in waist circumference [one year]
7. change in waist- to- hip ratio [one year]
8. change in systolic blood pressure [one year]
9. change in insulin resistance [one year]
10. change in hemoglobin A1C in diabetes patients [one year]
11. change in total cholesterol [one year]
12. change in high density lipoprotein cholesterol [One year]
13. Change in triglyceride levels [One year]
14. change in low density lipoprotein cholesterol [one year]
15. change in apolipoprotein A1 [one year]
16. change in Apolipoprotein B [One year]
17. change in Apolipoprotein A1 to B ratio [one year]
18. change in total cholesterol to high density lipoprotein cholesterol ratio [one year]
19. change in high sensitivity C-reactive protein [one year]
20. change in antihypertensive medication use [one year]
21. change in antihyperglycemic medication [one year]
22. change in lipid- lowering medications [one year]
23. change in diastolic blood pressure [one year]