Primary Prevention of Type 2 Diabetes: A Randomized Control Trial With Interactive Smartphone App to Restore Optimal Weight in Women With Recent Gestational Diabetes
Phase: NA
Conditions: Gestational Diabetes, Weight Loss, Diet Habit
Sponsor: National University Hospital, Singapore

POST GDM APP STUDY PROTOCOL V3.0, 01/11/2017 
 
SPAROW STUDY PROTOCOL 
Objectives: 
1. To conduct a randomized control trial to examine the efficacy of an INTERACTIVE 
SMARTPHONE APP, customized for Singaporean women with recent GDM, in optimizing 
post-delivery weight and metabolic profiles compared with standard care. 
 Primary outcome: Restoration of booking weight if previous booking BMI = 23; Weight 
loss of 5% with respect to booking weight if BMI > 23 
 Secondary outcomes: Improved cardiometabolic and inflammatory markers: fasting 
and 2h post-glucose load plasma glucose in an oral glucose tolerance test, HbA1C, 
advanced glycation end-products, C-peptide, HOMA-IR, lipid profile, liver function, 
hsCRP, IL-6.2. 
2. Evaluate the relative cost-effectiveness of this INTERACTIVE SMARTPHONE APP compared 
to standard care within the Singapore healthcare system in terms of improvements in 
quality of life, feasibility, acceptability, scalability and sustainability. 
 
Design: 
During the antenatal period, subjects will be informed about the study during regular NUH 
GDM consultations. After delivery, women will be offered the opportunity to join the study. 
Informed consent will be obtained at the 36-41 week follow-up visit or if the patient is 
admitted to hospital between 36-41 weeks of gestation. An appointment will be given for the 
first study visit at 6-12 weeks post-delivery. After delivery before discharge, subject’s height 
and weight will be taken. Women will undergo a 75gm OGTT. Fasting blood would be stored 
for metabolic assessments. Validated questionnaires on health status, diet, physical activity, 
and quality of life as listed below in secondary outcomes will be obtained. 
 
RANDOMIZATION: 
Participants would be randomized after informed consent has been obtained to either 
STANDARD care or INTERACTIVE SMARTPHONE APP arms of the study. The team aims to 
randomize 200 subjects (n=100 in each arm) and estimate that a minimum of 64 subjects 
will complete the study in each arm. The team has factored in a total of 15% attrition from 
postnatal diagnosis of type 2 diabetes, voluntary attrition and lost to follow-up. 
 
INTERVENTIONS: 
A) STANDARD CARE ARM: Subjects in the standard care arm will be informed of their 
increased risk of developing type 2 diabetes in the future, and given general lifestyle advice 
to maintain a healthy weight, eat a well-balanced diet and do regular exercise during their 6- 
week postnatal visit. Women found to have impaired fasting glucose (6.1-6.9 mmol/L) or 
impaired glucose tolerance (2H post glucose of 7.8-11.0 mmol/L) will be issued a letter 
reinforcing lifestyle changes namely weight loss (if raised BMI), diet, exercise, and 
encouragement to consult a family physician to discuss the appropriateness of starting 
medications that can prevent the progression to type 2 diabetes, or restore the blood glucose 
to normal levels. Those with a normal OGTT result will just be informed that it is normal. 
B) INTERACTIVE SMARTPHONE APP ARM: Participants will download the INTERACTIVE 
SMARTPHONE APP and will be briefed on its use by our team of nutritionists/ dieticians, 
exercise physiologists and lifestyle coaches. Patients will also be given a digital weighing 

POST GDM APP STUDY PROTOCOL V3.0, 01/11/2017 
 
machine to chart their weight weekly if they do not already own one. About 4 months after 
delivery, participants will return to the outpatient clinic for OGTT, HbA1C, advanced glycation 
end-products, C-peptide, HOMA-IR, lipid profile, liver function, hsCRP, and IL-6 testing, as well 
as the same validated questionnaires that they had completed during their previous visit. This 
will be their last visit pertaining to the study and will be discharged from the study. 
 
Methods: 
For the main analysis, the primary outcomes are the proportion of women attaining a 
satisfactory weight at 4 months post-delivery. The team will aim for a minimally important 
effect of a doubling in the proportion of women who attain their target weight, corresponding 
to 40% of women in the intervention group attaining their target weight (or less) and 20% in 
the control group. For a standard power of 80% and alpha of 0.05, the sample size required 
in each group to detect this effect is 64 individuals. To account for a potential 15% attrition 
rate, the team aims to recruit 75 individuals in each group. 
 
Subject’s visits: 
VISIT 1 (6-12 weeks postnatal): Blood taking: at 0hr and 2hr for oral glucose tolerance test. 
HbA1C, advanced glycation end-products, C-peptide, HOMA-IR, lipid profile, liver function, 
hsCRP, and IL-6. Questionnaires: Patients will be asked to fill up a series of questionnaires that 
will cover their health status, diet, physical activity, and quality of life. An optional 10ml of 
additional blood will be collected for storage for use in future studies regarding the 
management of recent gestational diabetes. 
 
VISIT 2 (about 4 months postnatal): Blood taking: at 0hr and 2hr for oral glucose tolerance 
test. HbA1C, advanced glycation endproducts, C-peptide, HOMA-IR, lipid profile, liver 
function, hsCRP, and IL-6. Patients will be asked to fill up a series of questionnaires that will 
cover their health status, diet, physical activity, and quality of life. An optional 10ml of 
additional blood will be collected for storage for use in future studies regarding the 
management of recent gestational diabetes. 
 
Details of investigations performed: 
 Blood taking for: OGTT, blood metabolic markers (C-peptide, insulin, HbA1C, lipid profile, 
liver function, hsCRP), blood for future research 
 Measurements: Height, weight 
 Questionnaires: 
1) 3-Day food diary, 
2) Self-Efficacy to regulate eating habits questionnaire, 
3) Self-Efficacy to regulate exercise questionnaire, 
4) Health Education Impact (heiQ), 
5) RAND-12 health questionnaire, 
6) Health Expenditure questionnaire. 
 
Inclusion criteria: 
Female aged 21 years and above; Plans to deliver in NUH; Diagnosed with GDM antenatally 
(between 12-34 weeks gestation) defined using the 2013 World Health Organization criteria; 

POST GDM APP STUDY PROTOCOL V3.0, 01/11/2017 
 
Has a smartphone and able to independently use a smartphone app; Willing to provide a 
blood sample; Able to give written informed consent; Able to speak and read English. 
 
Exclusion criteria: 
Subjects with type 1 and type 2 diabetes (including suspected cases diagnosed by an 
abnormal oral glucose tolerance test in the 1st and early 2nd trimesters of pregnancy); Drugs 
that affect glucose or lipid metabolism; Terminal or life threatening condition; Physical or 
mental condition that would prevent completion of a majority of study instruments.