Effects of telephone-delivered lifestyle support on the development of diabetes in participants at high risk of type 2 diabetes: J-DOIT1, a pragmatic cluster randomised trial.
OBJECTIVE
To examine the effects of telephone-delivered lifestyle coaching on preventing the development of type 2 diabetes mellitus (T2DM) in participants with impaired fasting glucose (IFG).


METHODS
Cluster randomised trial.


METHODS
40 groups from 17 healthcare divisions in Japan: companies (31), communities (6) and mixed settings (3).


METHODS
Participants aged 20-65 years with fasting plasma glucose (FPG) of 5.6-6.9 mmol/L were invited from the 17 healthcare divisions.


METHODS
The groups were then randomly assigned to an intervention or a control arm by independent statisticians according to a computer-generated list.


METHODS
The intervention arm received a 1-year telephone-delivered intervention provided by three private lifestyle support centres (at different frequencies: low-frequency (3 times), middle-frequency (6 times) and high-frequency (10 times) support calls). The intervention and control arms both received self-help devices such as a weight scale and pedometer.


RESULTS
Participants were followed up using data from annual health check-ups and a questionnaire regarding lifestyle. The primary outcome was the development of T2DM defined as FPG ≥ 7.0 mmol/L, the diagnosis of diabetes, or use of an antidiabetic drug, confirmed by referring to medical cards.


RESULTS
Of 14,473 screened individuals, participants were enrolled in either the intervention (n = 1240) arm or control (n = 1367) arm. Overall, the HR for the development of T2DM in the intervention arm during 5.5 years was 1.00 (95% CI 0.74 to 1.34). In the subanalysis, the HR was 0.59 (95% CI 0.42 to 0.83) in the subgroup that received phone calls the most frequently, compared with the control arm. A limitation of the study includes a lack of blinding.


CONCLUSIONS
High-frequency telephone-delivered lifestyle support could effectively prevent T2DM in participants with IFG in a primary healthcare setting, although low-frequency and middle-frequency phone calls did not.


BACKGROUND
This trial has been registered with the University Hospital Medical Information Network (UMIN000000662).
Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
Naoki
N
Sakane
Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan Division of Community and Family Medicine, Juichi Medical University, Shimotsuke, Japan.
Kazuhiko
K
Kotani
Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan Hyogo Health Service Association, Kobe, Japan.
Kaoru
K
Takahashi
Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan Kanagawa University of Human Services Faculty of Health & Social Services School of Nutrition & Dietetics, Yokosuka, Japan.
Yoshiko
Y
Sano
Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
Kokoro
K
Tsuzaki
Department of Development for Community-oriented Healthcare System, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Kentaro
K
Okazaki
Department of General Medicine/Family and Community Medicine, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Juichi
J
Sato
Department of Public Health, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Sadao
S
Suzuki
Department of Biomedical Statistics and Bioinformatics, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Satoshi
S
Morita
University of Marketing and Distribution Sciences, Kobe, Japan.
Yoshitake
Y
Oshima
Department of Diabetes and Metabolic Medicine, National Center for Global Health and Medicine, Tokyo, Japan.
Kazuo
K
Izumi
Department of Diabetes Research, Diabetes Research Center, National Center for Global Health and Medicine, Tokyo, Japan.
Masayuki
M
Kato
Clinical trial department, Cancer Institute hospital, Tokyo, Japan.
Naoki
N
Ishizuka
Department of Diabetes Research, Diabetes Research Center, National Center for Global Health and Medicine, Tokyo, Japan.
Mitsuhiko
M
Noda
Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan Takeda Hospital, Kyoto, Japan.
Hideshi
H
Kuzuya
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D003362:Cost-Benefit Analysis; D003376:Counseling; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D015438:Health Behavior; D006293:Health Promotion / Q000379:methods*; D006296:Health Services; D006801:Humans; D007564:Japan; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011236:Prediabetic State / Q000097:blood; D011320:Primary Health Care; D012306:Risk; D013689:Telephone
D001786:Blood Glucose
HEALTH SERVICES ADMINISTRATION & MANAGEMENT; PUBLIC HEALTH