Obesity and reduced levels of physical activity are directly associated with the insulin resistance that characterizes type 2 diabetes (1,2). Physical activity is one of the cornerstones of type 2 diabetes management (3). Few large studies have assessed the impact of intensity and quality of exercise on metabolic control in these patients, and the influence of age on the metabolic response to physical activity is still controversial (4). We conducted the Intervention on Key Cardiovascular Risk Factors in Type 2 Diabetes National Study (KAREN), a country-based case-control study nested in a survey of 1,485 consecutive type 2 diabetic patients treated by 208 endocrinologists across Spain to assess the impact of physical activity on metabolic control. Patient risk factors, history characteristics, medication and diet compliance, glycemia, fasting HbA1c, and lipids were determined.

Patient characteristics are presented in Table 1 by quartile of physical activity. After adjustment for age, sex, triglycerides, BMI, and diet compliance, patients in the lowest quartile of physical activity had an OR of 1.52 and a 95% CI of 1.11–2.08 for having an HbA1c >7.5%. The ORs for patients <65 years of age and in the lowest quartile of physical activity were 1.55 (95% CI 1.04–2.31) compared with the fourth, 1.64 (1.09–2.47) with the third, and 1.84 (1.22–2.75) with the second quartile. Patients >65 years of age and in the lowest quartile of physical activity had a similar adjusted risk compared with the rest of quartiles (OR 1.14, 95% CI 0.70–1.85; 1.38, 0.84–2.26, and 0.87, 0.53–1.43, respectively). A significant reduction of 0.2% (95% CI −0.36 to −0.04) in HbA1c was observed for patients expending >50 kcal/day versus the first quartile; the reduction for patients ≤65 years of age was 0.27% (−0.49 to −0.06), but for patients >65 there was no significant difference.

These results suggest that physical activity produces better glycemic control and improved cardiovascular risk profile in diabetic patients, particularly in those <65 years of age.

The KAREN Investigators comprise 208 Spanish endocrinologists who work in primary outpatient diabetes clinics of the National Health Service.

The KAREN investigators are as follows: Abellán T, Acha FJ, Acosta D, Aguilar M, Aguillo E, Albero R, Alcaraz M, Alvarez JA, Alvarez P, Alvarez J, Andia VM, Aranda S, Arranz A, Arribas LD, Arteaga R, Asensio C, Ayala C, Ballester E, Barril R, Becerra A, Blanco B, Blay V, Botas P, Brito MA, Bruscas M, Bueno J, Burgo R, Cabezas J, Calderón D, Calero M, Calvo F, Cáncer E, Carrasco R, Casal F, Castaño G, Castro JC, Cepero D, Cervello G, Chena JA, Conget I, Corrales JJ, Costilla E, Coves MJ, Darías R, de la Cuesta C, de Pablos P, Díaz C, Diez A, Domínguez JR, Duran S, Duran M, Elviro R, Enríquez L, Escalada FJ, Escobar L, Esmatges E, Espiga J, Estopiñan V, Ezquerra R, Famades A, Fernández JI, Fernández M, Fernández JM, Fernández F, Fernández T, Fernández JA, Fernández J, Flández B, Flaquert P, Fraile AL, Fraile J, Freijanes J, Galvez A, García JA, García A, García C, García G, García I, García J, García M, Garcia-Hierro V, Gargallo MA, Gentil AC, Gil A, Gilsanz A, Giménez G, Gippini A, Girbés AJ, Goday A, Godoy DV, Goena M, Goicolea I, Gómez F, González A, González JM, González O, Goñi F, Guerrero E, Hernández C, Hernández A, Hernández JA, Hernández C, Hernández A, Hernández C, Iglesias P, Ikobalceta P, Illan F, Iñigo P, Iriarte A, Irigoyen L, Jaunsolo MA, Lain T, Levy I, Llorente I, López AJ, López de la Torre M, López-Guzman A, Losada F, Luna R, Macanas G, Macia C, Maldonado JA, Mangas MA, Manzanares JM, Maravall FJ, Marco A, Marco AL, Marin M, Martín T, Martín A, Martínez MP, Martínez FJ, Martínez MA, Matia P, Mato JA, Megia A, Menéndez E, Meoro A, Merino JF, Mesa J, Mezquita P, Micalo T, Miralles JM, Molina MJ, Monereo S, Morales MJ, Moreno A, Moreno C, Mories T, Muñoz L, Muñoz M, Muñoz A, Muros T, Nubiola A, Oleaga A, Oliván B, Palacios N, Palomares R, Pazos F, Pena E, Peñafiel FJ, Pereyra F, Pérez A, Pesquera C, Picon MJ, Piedrola G, Pinedo R, Piniés J, Pizarro E, Prieto J, Puig M, Puigdevall V, Pumar A, Recas I, Recio JM, Reverter J, Ricart W, Rius F, Rivas M, Rosell R, Rubio JA, Ruiz JM, Sagarra E, Sales J, Salinas I, Sánchez C, Sánchez JC, Santiago P, Santiago L, Sastre J, Segura P, Simo R, Simón I, Solache I, Soriano J, Soto A, Suarez-Lledo E, Surruca L, Tebar FJ, Tenes T, Todolí J, Tofe S, Tolosa M, Torras R, Torres A, Vadillo V, Velasco JL, Vences LF, Vendrell JJ, Vicente A, Vidal JI, Villa M, Villar A, Zurro J.

Table 1—

Demographic, comorbidity, lifestyle, biochemical, and somatometric characteristics by physical activity levels (quartiles) of type 2 diabetic patients who participated in the KAREN study

<51 kcal/day51–148 kcal/day149–264 kcal/day>264 kcal/dayP
n 368 373 375 369  
Age (years) 62 ± 10 61 ± 10 61 ± 9 61 ± 10 NS 
Women (%) 49.6 45.3 54.4 69.6 <0.001 
Time with diabetes (years) 10.3 ± 6.4 9.9 ± 6.3 10.1 ± 6.4 10.3 ± 6.2 NS 
Hypertension (%) 51.8 58.3 50.7 46.3 0.017 
Current smokers (%)* 19.4 18.9 19.0 16.0 NS 
Systolic BP (mmHg) 140 ± 17 139 ± 17 139 ± 16 139 ± 19 NS 
Diastolic BP (mmHg) 80 ± 10 79 ± 9 79 ± 10 78 ± 11 NS 
BMI (kg/m2) 28.8 ± 3.4 28.5 ± 3.5 28.1 ± 3.3 28.3 ± 3.3 0.035 
Coronary heart disease (%)† 17.9 14.4 18.0 14.0 NS 
Cerebrovascular disease (%)‡ 8.5 6.4 6.6 5.1 NS 
Glycemia (mg/dl) 9.5 ± 3.2 9.1 ± 2.9 9.1 ± 3.0 8.8 ± 2.7 <0.001 
HbA1c (%)* 7.9 ± 1.6 7.6 ± 1.4 7.6 ± 1.4 7.4 ± 1.0 <0.001 
Total cholesterol (mmol/l) 5.3 ± 1.0 5.4 ± 1.0 5.2 ± 1.0 5.1 ± 1.0 <0.001 
HDL cholesterol (mmol/l) 1.2 ± 0.3 1.3 ± 0.3 1.2 ± 0.3 1.3 ± 0.4 0.014 
LDL cholesterol (mmol/l) 3.4 ± 0.9 3.4 ± 0.9 3.2 ± 34.7 3.3 ± 0.9 NS 
Triglycerides (mmol/l) 1.9 ± 1.8 1.7 ± 0.9 1.7 ± 1.1 1.5 ± 0.9 <0.001 
Creatinine (μmol/l) 91.9 ± 31.8 85.7 ± 24.7 86.6 ± 26.5 88.4 ± 19.4 0.035 
Good diet compliance (%) 37.1 35.1 49.2 52.2 <0.001 
Daily alcohol consumption (g) 12.9 ± 12.8 12.5 ± 12.3 12.8 ± 13.3 12.5 ± 12.3 NS 
<51 kcal/day51–148 kcal/day149–264 kcal/day>264 kcal/dayP
n 368 373 375 369  
Age (years) 62 ± 10 61 ± 10 61 ± 9 61 ± 10 NS 
Women (%) 49.6 45.3 54.4 69.6 <0.001 
Time with diabetes (years) 10.3 ± 6.4 9.9 ± 6.3 10.1 ± 6.4 10.3 ± 6.2 NS 
Hypertension (%) 51.8 58.3 50.7 46.3 0.017 
Current smokers (%)* 19.4 18.9 19.0 16.0 NS 
Systolic BP (mmHg) 140 ± 17 139 ± 17 139 ± 16 139 ± 19 NS 
Diastolic BP (mmHg) 80 ± 10 79 ± 9 79 ± 10 78 ± 11 NS 
BMI (kg/m2) 28.8 ± 3.4 28.5 ± 3.5 28.1 ± 3.3 28.3 ± 3.3 0.035 
Coronary heart disease (%)† 17.9 14.4 18.0 14.0 NS 
Cerebrovascular disease (%)‡ 8.5 6.4 6.6 5.1 NS 
Glycemia (mg/dl) 9.5 ± 3.2 9.1 ± 2.9 9.1 ± 3.0 8.8 ± 2.7 <0.001 
HbA1c (%)* 7.9 ± 1.6 7.6 ± 1.4 7.6 ± 1.4 7.4 ± 1.0 <0.001 
Total cholesterol (mmol/l) 5.3 ± 1.0 5.4 ± 1.0 5.2 ± 1.0 5.1 ± 1.0 <0.001 
HDL cholesterol (mmol/l) 1.2 ± 0.3 1.3 ± 0.3 1.2 ± 0.3 1.3 ± 0.4 0.014 
LDL cholesterol (mmol/l) 3.4 ± 0.9 3.4 ± 0.9 3.2 ± 34.7 3.3 ± 0.9 NS 
Triglycerides (mmol/l) 1.9 ± 1.8 1.7 ± 0.9 1.7 ± 1.1 1.5 ± 0.9 <0.001 
Creatinine (μmol/l) 91.9 ± 31.8 85.7 ± 24.7 86.6 ± 26.5 88.4 ± 19.4 0.035 
Good diet compliance (%) 37.1 35.1 49.2 52.2 <0.001 
Daily alcohol consumption (g) 12.9 ± 12.8 12.5 ± 12.3 12.8 ± 13.3 12.5 ± 12.3 NS 

Data are means ± SD and %.

*

Smokers of at least one cigarette per day in average;

†

myocardial infarction or angina;

‡

transient ischemic attack or stroke.

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Address correspondence to Dr. Jaume Marrugat, Lipid and Cardiovascular Epidemiology Unit, Institut Municipal d’Investigació Mèdica (IMIM), Carrer Dr. Aiguader, 80, E-08003 Barcelona, Spain. E-mail: [email protected].

DIABETES CARE
2003