Epidemiology, Screening, and Diagnosis of Diabetes in Spain

Epidemiology

Diabetes is a major health problem in Spain, affecting about 3,000,000 people out of a total population of approximately 43,000,000; this number is expected to rise to 3,752,000 in the next 25 years.[1],[2] Currently, Spain has one of the highest diabetes prevalence rates in Europe (see Table 1).[3] Some estimates reach as high as 9.9%, placing it among the top 10 countries in the world. The average prevalence among countries in the European Union (EU) was 7.5% in 2003, ranging from 10.2% in Germany to 3.4% in Ireland.[3] Further, there may be as many as 3 cases of undiagnosed diabetes for every known case in the Spanish population.[] Of patients with diabetes in Spain, about 10% have type 1, and about 90% percent, have type 2.[4] Other categories of disease, such as gestational diabetes and maturity onset diabetes of the young (MODY), constitute a smaller percentage of cases and will not be discussed in this article.

Data from population screening programs across the EU indicate that up to 50% of all people with diabetes are undiagnosed, and about half of those who are diagnosed with type 2 diabetes already have evidence of at least one complication.[3] The number of patients with diabetes is expected to increase across the EU by approximately 20% over the next 20 years, as the incidence of type 2 diabetes in ever-younger patients increases.[3] One 1987 study by the Spanish Ministry of Health and Consumption (Ministerio de Sanidad y Consumo) showed a prevalence of diagnosed diabetes among persons aged 1 to 15 years of 0.3%.[5]

Table 1. Top 10 countries based upon prevalence of diabetes among the 20-79 year-old age group, 2003 data[4]

The increasing prevalence of diabetes takes a tremendous toll on society, both in terms of general economic impact and the quality of life of the individual patient. Direct costs of the treatment of patients with diabetes in Spain totaled between €2.4-2.6 billion in 2002, representing 5-6% of total national healthcare spending.[6] Specific costs are detailed in Table 2. A recent study estimated the direct costs of diabetes in Spain at 7.4% of the total national healthcare expenditure.[6]

Table 2. Direct costs of diabetes care in Spain, 2002[6]

The Cost of Diabetes in Europe—Type 2 study (CODE-2), which measured the total healthcare costs for patients with type 2 diabetes in 8 European countries (Belgium, France, Germany, Italy, the Netherlands, Spain, Sweden, and the UK), found the total yearly (1998) costs for people with type 2 diabetes across these 8 countries to be approximately €28,500,000,000, and in Spain alone to be almost €1,900,000,000, a per-patient expenditure of at least €1300.[7] Among patients with type 2 diabetes in Spain examined by the CODE-2 study, 8.3% were hospitalized during the 6-month study, with an average hospital stay of 8 days.[7] The cost of hospitalizations accounted for the largest portion of total costs for all countries in the study, at 55%, leading non-antidiabetic drugs (21%), outpatient care (18%) and antidiabetic drugs (7%).[7] Among non-antidiabetic drugs, the majority of them were cardiovascular and lipid-lowering (42%).[7]

Screening for Diabetes

The Ministerio de Sanidad y Consumo recommends screening with fasting blood glucose for all people older than 45 years.[7] A person with a normal result should be retested at 3-year intervals thereafter.[8] Regardless of age, screening fasting blood glucose should be conducted every year in individuals with any of the following risk factors:[8]

• History of gestational diabetes,impaired glucose tolerance (IGT), or impaired fasting glucose (IFG)[8]
• Women with previous birth to macrosomic child (more than 4500 g)[8]
• Obesity (BMI of 27 or greater, or weight ≥120% of ideal weight)[8]
• Hypertension (>140/90 mm Hg)[8]
• Dyslipidemia (HDL <35mg/dL) and/or hypertriglyceridemia (>250 mg/dL)[8]
• Family history of diabetes in first-degree relatives[8]

Fasting blood glucose (FBG) levels at diagnosis may indicate to a degree the duration or severity of diabetes.[9] A post-hoc analysis of t he United Kingdom Prospective Diabetes Study (UKPDS) demonstrated that FBG at study entry was related to the frequency of subsequent complications, with lower FBG (<7.8 mmol/L) associated with lower rates of all major endpoints, diabetes-related death rates, and myocardial infarction rates, suggesting a benefit of intervening either at lower FBG levels or earlier in the history of disease.[9] This finding suggests that clinical benefits can be derived from early detection.[9]

Screening for diabetes may also identify individuals with lesser degrees of hyperglycemia (eg, IGT, IFG) who would benefit from interventions to prevent or delay progression to diabetes.[9]

Diagnosis

Diagnosis of diabetes is made on the basis of clinical symptoms and/or elevated plasma glucose concentration as set forth by accepted criteria. The diagnostic criteria for diabetes adopted by the World Health Organization (WHO) and the American Diabetes Association (ADA) are both generally accepted in Spain.[8] In classically symptomatic patients (eg, patients with polyuria, polydipsia, weight loss), only 1 positive test is required for diagnosis; 2 tests, performed on separate days, are required in asymptomatic patients.[8] In addition to the etiological distinction between type 1 and type 2 diabetes, the terms “impaired glucose tolerance” (IGT, known in Spain as Tolerancia alterada a la glucosa or TAG) and “impaired fasting glycemia” (IFG, known in Spain as Glucemia basal alterada or GBA) are used to describe risk categories for cardiovascular disease (IGT/TAG) and/or future diabetes (IFG/GBA).[8] Diagnostic criteria for diabetes, IGT (TAG), and IFG (GBA) appear in Table 3.

Table 3. Current diagnostic criteria for diabetes, IGT (TAG), and IFG (GBA)[8]

References

1. http://www.who.int/diabetes/facts/world_figures/en/index4.html. Accessed May 2006.
2. http://www.who.int/countries/esp/en/. Accessed May 2006.
3. International Diabetes Federation. Diabetes: the policy puzzle: towards benchmarking in the EU 25. Available at http://www.idf.org/webdata/docs/idf-europe/DiabetesReport2005.pdf. Accessed May 2006.
4. IDF Diabetes Atlas Executive Summary. Available at: http://www.eatlas.idf.org/Diabetes_Atlas___Executive_Summary_download/.
5. Goday A. Epidemiology of diabetes and its non-coronary complications. Rev Esp Cardiol. 2002;55:657-670. Available at: www.revespcardiol.org.
6. Oliva J, Lobo F, Molina B, Monereo S. Direct health care costs of diabetics in Spain. Diabetes Care. 2004;27:2616-2621.
7. Jönsson B. Revealing the cost of Type II diabetes in Europe. Diabetologia. 2002;45:S5–S12.
8. www.msc.es/ en/ciudadanos/enfLesiones/enfNoTransmisibles/diabetes/diabetes.htm#prevencion.
9. IDF Global guideline for Diabetes. Available at: http://www.idf.org/webdata/docs/IDF%20GGT2D.pdf. Accessed March 2006.