Trends in the prevalence of diabetes and impaired fasting glucose in association with obesity in Iran: 2005-2011.
OBJECTIVE
To estimate the prevalence and trends of diabetes mellitus (DM) and impaired fasting glucose (IFG), 2005-2011, and to determine the contribution of obesity to DM prevalence.


METHODS
Data from Surveillance of Risk Factors of Non-communicable Diseases (SuRFNCD) conducted in 2005, 2007, and 2011 were gathered. DM was defined as presence of self-reported previous diagnosis or a fasting plasma glucose (FPG)≥7 mmol/L. IFG was diagnosed with FPG levels between 5.6 and 6.9 mmol/L. Prevalence rates for 2011 and trends for 2005-2011 were determined by extrapolating survey results to Iran's adult population. Population attributable fraction (PAF) of obesity was also calculated.


RESULTS
In 2011, IFG and total DM prevalence rates were 14.60% (95%CI: 12.41-16.78) and 11.37% (95%CI: 9.86-12.89) among 25-70 years, respectively. DM was more common in older age (p < 0.0001), in women (p = 0.0216), and in urban-dwellers (p = 0.0001). In 2005-2011, trend analysis revealed a 35.1% increase in DM prevalence (OR: 1.04, 95%CI: 1.01-1.07, p = 0.011); albeit, IFG prevalence remained relatively unchanged (OR: 0.98, 95%CI: 0.95-1.00, p = 0.167). In this period, DM awareness improved; undiagnosed DM prevalence decreased from 45.7% to 24.7% (p < 0.001). PAF analysis demonstrated that 33.78%, 10.25%, and 30.56% of the prevalent DM can be attributed to overweight (BMI≥25kg/m(2)), general obesity (BMI≥30 kg/m(2)), and central obesity (waist circumference≥90 cm), respectively. Additionally, the DM increase rate in 2005-2011, was 20 times higher in morbidly obese compared with lean individuals.


CONCLUSIONS
More than four million Iranian adults have DM which has increased by 35% over the past seven years, owing in large part, to expanding obesity epidemic.
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Esteghamati@tums.ac.ir.
Alireza
A
Esteghamati
Center for Disease Control, Tehran, Iran. Electronic address: Etemad@Health.gov.ir.
Koorosh
K
Etemad
Center for Disease Control, Tehran, Iran. Electronic address: J-koohpayezadeh@sina.tums.ac.ir.
Jalil
J
Koohpayehzadeh
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Meabbasi@sina.tums.ac.ir.
Mehrshad
M
Abbasi
Department of Preventive Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Meysamie@tums.ac.ir.
Alipasha
A
Meysamie
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Sina.noshad@gmail.com.
Sina
S
Noshad
Center for Disease Control, Tehran, Iran. Electronic address: Asgarifcdc@yahoo.com.
Fereshteh
F
Asgari
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: S.m.mousavizadeh@gmail.com.
Mostafa
M
Mousavizadeh
Center for Disease Control, Tehran, Iran. Electronic address: Rafei@health.gov.ir.
Ali
A
Rafei
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Elyas.khajeh@gmail.com.
Elias
E
Khajeh
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: M.neishaboury@gmail.com.
Mohamadreza
M
Neishaboury
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Shb.sara@yahoo.com.
Sara
S
Sheikhbahaei
Endocrinology and Metabolism Research Center (EMRC), Vali-Asr Hospital, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: Nakhjavanim@tums.ac.ir.
Manouchehr
M
Nakhjavani
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D003920:Diabetes Mellitus / Q000097:blood / Q000453:epidemiology*; D005215:Fasting / Q000097:blood*; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000453:epidemiology*; D015995:Prevalence; D055105:Waist Circumference
D001786:Blood Glucose
Diabetes mellitus; Impaired fasting glucose; Obesity; Population attributable fraction; Surveillance of Risk Factors of Non-communicable Diseases; Trends