Prevalence of diabetes mellitus and obesity in the general adult population of Greece: a door‐to‐door epidemiological study

In this cross-sectional, door-to-door, epidemiological study, we examined the prevalence of known diabetes mellitus (DM) and obesity, an established risk factor of Type 2 DM [1], in a sample of theadult Greek population. This studywas run in parallel with the ESORDIG Study, which examined the prevalence of rheumatic diseases in Greece. Details of the ESORDIG study design, study population, subject recruitment and evaluation have been reported previously [2,3]. Briefly, the study was conducted from 1996 to 1999 and included the total adult population (aged ‡ 19 years) of seven areas covering urban, suburban and rural areas located in the northern, central and southern mainland of Greece (8547 subjects) and on a random sample of 2100 subjects of one rural and one suburban area. Thus, the final target adult population was 10 647 subjects. As described in detail previously, the study sample was representative of the general adult population of Greece [2,3]. The study protocol was approved by the appropriate local and central committees and was conducted according to the recommendations of the Declaration of Helsinki. Diagnosis of DM was based on the following: participants had a history of DM diagnosed by the family doctor or the primary care physician and ⁄ or they were prescribed treatment with oral glucose-lowering agents, insulin alone or combination of oral glucose-lowering agents and insulin [4]. Gestational and other types of DM were excluded. When the onset of DM was < 30 years of age in the presence of symptoms of diabetes and ⁄ or ketoacidosis and the patients had been treated continuously with insulin, DM was considered as Type 1 DM; all other cases were considered asType 2DM. Participants wereasked to report their weight and height, which were used to calculate the body mass index (BMI), and they were classified as normal weight (BMI < 25.0 kg ⁄ m), overweight (BMI 25.0–29.99 kg ⁄ m) and obese (BMI ‡ 30.0 kg ⁄ m). Of the final target adult population of 10 647 subjects, 8740 participated in the study (participation rate 82.1%). Forty-nine per cent of the participants were men and 51% were women, while 31% were residents in urban, 34% in suburban and 35% in rural areas; the mean age was 47.0 17.7 years. Analysis in a random sample of non-participants (n = 60), who did not participate in the full survey, but who later agreed to complete a brief questionnaire on diabetes, showed no significant differences from responders with respect to age, sex, BMI and prevalence of DM. Additionally, the reasons for nonparticipation were unrelated to DM or to BMI status. Of the 8740 participants, 375 [4.29%, 95% confidence interval (CI) 4.24–4.33] had known DM; 360 (4.11%, 95% CI 3.70–4.52) had Type 2 DM and 15 (0.17%, 95% CI 0.14–0.19) had Type 1 DM. Table 1 illustrates the age and gender distribution of Type 2 DM. An increasing prevalence of the disease was observed by age group for both genders (P for trend < 0.001). Prevalence of known Type 2 DM did not differ significantly between males and females or among the northern, central and southern areas of the country. The mean age at diagnosis of Type 1 DM was 13.2 3.5 years. No significant gender differences were found in the prevalence of Type 1 DM and the prevalence was similar in all age groups, in northern, central and southern areas, and in those living in rural, urban and suburban areas of the country. Overall, 38.6% (95% CI 37.57–39.62) of the participants were overweight and 12.3% (95% CI 11.61–12.98) were obese (Table 1). Men were significantly more likely to be overweight than women (P < 0.001), while no gender differences were found in the prevalence of obesity. Of those with obesity, 10.2% had BMI 30.0–34.99 kg ⁄ m, 1.7% had BMI 35.0–39.99 kg ⁄ m and 0.4% had BMI ‡ 40 kg ⁄ m.