Trends in population attributable fraction of acute coronary syndrome and ischaemic stroke due to diabetes in Finland.

AIMS/HYPOTHESIS: Cardiovascular disease (CVD) event rates are decreasing, but the prevalence of diabetes is increasing. The effect of these developments on the population attributable fraction (PAF) of CVD events due to diabetes is not known. METHODS: We used country-wide healthcare registers to identify all persons aged 25-80 years treated for diabetes in Finland during 1992-2002. These data were further linked to the National Cardiovascular Disease Register to identify the first CVD events (acute coronary syndrome and ischaemic stroke) among the individuals with and without diabetes. We calculated the annual PAF of the first CVD events due to diabetes separately for men and women. RESULTS: The number of men treated for diabetes each year almost doubled during the study period from 37,073 to 69,158 between 1992 and 2002. Among women, the number increased from 42,485 to 57,372. The annual number of first CVD events in the country declined among men with diabetes from 13,436 to 12,678 and among women with diabetes from 8,658 to 7,521 between 1992 and 2002. During the same period, the PAF due to diabetes of the first CVD events increased among men from 11.4% (95% CI 10.8, 12.0%) to 13.8% (95% CI 13.2, 14.5%) and decreased among women from 20.1% (95% CI 19.2, 21.0%) to 16.9% (95% CI 15.9, 17.8%). The trends in PAF were different between the sexes (p < 0.001 for the interaction year × sex). CONCLUSIONS/INTERPRETATION: Despite the very large increase in the prevalence of diabetes, the PAF of the first CVD events due to diabetes decreased in women and increased only slightly in men.

Feasibility and compliance in a nutritional primary prevention trial in infants at increased risk for type 1 diabetes.

AIM: The international Trial to Reduce IDDM in the Genetically at Risk (TRIGR) was launched to determine whether weaning to a highly hydrolysed formula in infancy reduces the incidence of type 1 diabetes in children at increased genetic disease susceptibility. We describe here the findings on feasibility and compliance from the pilot study. METHODS: The protocol was tested in 240 children. The diet of the participating children was assessed by self-administered dietary forms, a structured questionnaire and a food record. Blood samples were taken and weight and height measured at birth and at 3, 6, 9, 12, 18 and 24 months. RESULTS: A majority of the subjects (84%) were exposed to the study formula at least for 2 months. Linear growth or weight gain over the first 2 years of life was similar in the two study groups. The levels of IgA and IgG antibodies to cow's milk and casein were higher in the cow's milk-based formula group than in the hydrolysed formula group during the intervention period (p<0.05), reflecting the difference in the intake of cow's milk protein. CONCLUSION: This randomized trial on infant feeding turned out to be feasible, and dietary compliance was acceptable. Valuable experience was gained for the planning and sample size estimation of the study proper.

Case fatality rates after first acute coronary syndrome in persons treated for type 2 diabetes show an improving trend.

AIMS/HYPOTHESIS: We analysed whether the prognosis of a first acute coronary syndrome (ACS) in patients treated for type 2 diabetes has improved. We also compared the trends in patients with and without diabetes. METHODS: We used national registers to identify all patients with clinically known type 2 diabetes in Finland during the years 1988 to 2002 (n = 222,940). All first-ever ACS events (n = 43,412) among these patients were identified using the Hospital Discharge Register and the Causes of Death Register. From the National Cardiovascular Disease Register we identified all first ACS attacks (n = 191,403) among non-diabetic patients in the country. Finally, we calculated annual age-standardised case fatality rates for ACS for three time periods: prehospital, days 0 to 27 and days 28 to 364 after the first ACS. RESULTS: The case fatality rate of first ACS declined significantly in both sexes at all time points considered. The declining trends were not different between patients with type 2 diabetes and those without. Among men aged 35 to 74 years, 58.5% (95% CI 57.6-59.4%) with type 2 diabetes and 44.1% (95% CI 43.8-44.5%) without diabetes had died from cardiovascular causes 1 year after their first ACS. Among women of the same age, the corresponding figures were 54.2% (95% CI 53.0-55.4%) and 36.5% (95% CI 35.9-37.1%). Men generally had higher case fatality rates than women. However, except for prehospital deaths, diabetic women had the same or even higher case fatality rates than non-diabetic men. CONCLUSIONS/INTERPRETATION: The case fatality rates for first ACS show similar improving trends in patients with type 2 diabetes and in those without. However, case fatality rates have remained higher in patients with type 2 diabetes.

Malignancies in cases with screening-identified evidence of coeliac disease: a long-term population-based cohort study.

BACKGROUND AND AIMS: The association between diagnosed coeliac disease and malignancy has been established. The present study was conducted to determine whether previously unrecognised and thus untreated adults with screening-identified evidence of coeliac disease carry an increased risk of malignancies. METHODS: A Finnish population-based adult-representative cohort of 8000 individuals was drawn in 1978-1980. Stored sera of the participants with no history of coeliac disease or any malignancy were tested for immunoglobulin A (IgA) class tissue transglutaminase antibodies (Eu-tTG) in 2001. Positive sera were further analysed by another tissue transglutaminase antibody test (Celikey tTG) and for endomysial antibodies (EMAs). Malignant diseases were extracted from the nationwide database and antibody-positive cases were compared with negative cases during a follow-up of nearly 20 years. RESULTS: Altogether 565 of all the 6849 analysed serum samples drawn in 1978-80 were Eu-tTG positive. In further analyses, 202 (2.9%) of the participants were Celikey tTG positive and 73 (1.1%) were EMA positive. The overall risk of malignancy was not increased among antibody-positive cases in the follow-up of two decades; the age- and sex-adjusted relative risk was 0.91 (95% CI 0.60 to 1.37) for those who were Celikey tTG positive and 0.67 (95% CI 0.28 to 1.61) for those who were EMA positive. CONCLUSIONS: The prognosis of adults with unrecognised coeliac disease with positive coeliac disease antibody status is good as regards the overall risk of malignancies. Thus, current diagnostic practice is sufficient and there is no need for earlier diagnosis of coeliac disease by mass screening on the basis of the findings of this study.

Common candidate gene variants are associated with QT interval duration in the general population.

OBJECTIVES: QT interval prolongation is associated with increased risk of sudden cardiac death at the population level. As 30-40% of the QT-interval variability is heritable, we tested the association of common LQTS and NOS1AP gene variants with QT interval in a Finnish population-based sample. METHODS: We genotyped 12 common LQTS and NOS1AP genetic variants in Health 2000, an epidemiological sample of 5043 Finnish individuals, using Sequenom MALDI-TOF mass spectrometry. ECG parameters were measured from digital 12-lead ECGs and QT intervals were adjusted for age, gender and heart rate with a nomogram (Nc) method derived from the present study population. RESULTS: The KCNE1 D85N minor allele (frequency 1.4%) was associated with a 10.5 ms (SE 1.6) or 0.57 SD prolongation of the adjusted QT(Nc) interval (P=3.6 x 10(-11)) in gender-pooled analysis. In agreement with previous studies, we replicated the association with QT(Nc) interval with minor alleles of KCNH2 intronic SNP rs3807375 [1.6 ms (SE 0.4) or 0.08 SD, P=4.7 x 10(-5)], KCNH2 K897T [-2.6 ms (SE 0.5) or -0.14 SD, P=2.1 x 10(-7)] and NOSA1P variants including rs2880058 [4.0 ms (SE 0.4) or 0.22 SD, P=3.2 x 10(-24)] under additive models. CONCLUSIONS: We demonstrate that each additional copy of the KCNE1 D85N minor allele is associated with a considerable 10.5 ms prolongation of the age-, gender- and heart rate-adjusted QT interval and could thus modulate repolarization-related arrhythmia susceptibility at the population level. In addition, we robustly confirm the previous findings that three independent KCNH2 and NOSA1P variants are associated with adjusted QT interval.

Prevalence and prognostic significance of short QT interval in a middle-aged Finnish population.

BACKGROUND: Short-QT syndrome is an inherited disorder characterized by a short QT interval and an increased risk of sudden cardiac death. The clinical significance of a short QT interval observed in a randomly recorded ECG is not known. Therefore, we assessed the prevalence and prognostic significance of a short QT interval in a general population. METHODS AND RESULTS: QT intervals were measured from the 12-lead ECGs of 10 822 randomly selected middle-aged subjects (5658 males, mean age 44+/-8.4 years) enrolled in a population study and followed up for 29+/-10 years. The end points were all-cause and cardiovascular mortality. In addition to Bazett's method (corrected QT interval, or QTc), the Fridericia (QTfc) and nomogram (QTnc) methods were used to correct the QT interval for heart rate. The cutoff values for short QT intervals were defined as 320 ms (very short) and 340 ms (short). The prevalence of QT interval <320 ms based on QTc, QTfc, and QTnc was 0.10%, 0.08%, and 0.06%, and the prevalence of QT interval <340 ms was 0.4%, 0.3%, and 0.3%, respectively. The majority of subjects with short QT intervals were males. All-cause or cardiovascular mortality did not differ between subjects with a very short or short QT interval and those with normal QT intervals (360 to 450 ms). There were no sudden cardiac deaths, aborted sudden cardiac deaths, or documented ventricular tachyarrhythmias among subjects with a QTfc <340 ms. CONCLUSIONS: A short QT interval does not appear to indicate an increased risk for all-cause or cardiovascular mortality in middle-aged nonreferral, community-based individuals.

Prospective study of coffee consumption and risk of Parkinson's disease.

OBJECTIVE: To examine the prediction of coffee consumption on the incidence of Parkinson's disease. SUBJECTS AND METHODS: The study population comprised 6710 men and women, aged 50-79 years and free from Parkinson's disease at the baseline. At baseline, enquiries were made about coffee consumption in a self-administered questionnaire as the average number of cups per day. During a 22-year follow-up, 101 incident cases of Parkinson's disease occurred. Parkinson's disease cases were identified through a nationwide registry of patients receiving medication reimbursement, which is based on certificates from neurologist. RESULTS: After adjustments for age, sex, marital status, education, community density, alcohol consumption, leisure-time physical activity, smoking, body mass index, hypertension and serum cholesterol, the relative risk for subjects drinking 10 or more cups of coffee per day compared with non-drinkers was 0.26 (95% confidence interval 0.07-0.99, P-value for trend=0.18). The association was stronger among overweight persons and among persons with lower serum cholesterol level (P-value for interaction=0.04 and 0.03, respectively). CONCLUSIONS: The results support the hypothesis that coffee consumption reduces the risk of Parkinson's disease, but protective effect of coffee may vary by exposure to other factors.

Indoleamine 2,3-dioxygenase activity associates with cardiovascular risk factors: the Health 2000 study.

Indoleamine 2,3-dioxygenase (IDO) is an important immunomodulator suppressing the activation of T lymphocytes, and its level in blood is increased in several autoimmune and inflammatory diseases. We have previously shown that this activity associates with several signs and risk factors of atherosclerosis in 24 to 39-year-old females. Now we repeat this analysis in an older population (n = 921, age range 46-76 years), i.e. in a population with more advanced atherosclerosis. IDO activity had a significant positive correlation in both sexes with carotid artery intima/media thickness (IMT), an early marker of atherosclerosis. In females, a significant negative correlation with HDL cholesterol and a positive correlation with triglycerides levels was observed. The association with IMT did not remain significant after adjustment with classical risk factors of atherosclerosis. It is thus concluded that IDO is a sensitive marker of atherosclerosis--or the inflammatory response associated with it--but does not have an independent role in the pathogenesis of this disease.

Increasing prevalence of coeliac disease over time.

BACKGROUND: The number of coeliac disease diagnoses has increased in the recent past and according to screening studies, the total prevalence of the disorder is around 1%. AIM: To establish whether the increased number of coeliac disease cases reflects a true rise in disease frequency. METHODS: The total prevalence of coeliac disease was determined in two population-based samples representing the Finnish adult population in 1978-80 and 2000-01 and comprising 8000 and 8028 individuals, respectively. Both clinically-diagnosed coeliac disease patients and previously unrecognized cases identified by serum endomysial antibodies were taken into account. RESULTS: Only two (clinical prevalence of 0.03%) patients had been diagnosed on clinical grounds in 1978-80, in contrast to 32 (0.52%) in 2000-01. The prevalence of earlier unrecognized cases increased statistically significantly from 1.03% to 1.47% during the same period. This yields a total prevalence of coeliac disease of 1.05% in 1978-80 and 1.99% in 2000-01. CONCLUSIONS: The total prevalence of coeliac disease seems to have doubled in Finland during the last two decades, and the increase cannot be attributed to the better detection rate. The environmental factors responsible for the increasing prevalence of the disorder are issues for further studies.

Home-measured blood pressure is more strongly associated with electrocardiographic left ventricular hypertrophy than is clinic blood pressure: the Finn-HOME study.

Electrocardiographic evidence of left ventricular hypertrophy (ECG-LVH) has a grave prognostic significance in hypertensive patients. The purpose of our study was to assess whether ECG-LVH is more strongly associated with home-measured blood pressure (BP) than with clinic BP, and whether the correlation between home BP and ECG-LVH increases with the number of home measurements performed. We studied a representative sample of the general adult population (1989 subjects 45-74 years of age) in Finland. Subjects included in the study underwent a clinical interview, electrocardiography and measurement of clinic BP (mean of two clinic measurements) and home BP (mean of 14 duplicate home measurements performed during 1 week). Home BP correlated significantly better than clinic BP with the Sokolow-Lyon voltage (home/clinic systolic: r=0.23/0.22, P=0.60; diastolic: r=0.17/0.12, P=0.009), Cornell voltage (systolic: r=0.30/0.25, P=0.004; diastolic: r=0.21/0.12, P<0.001) and Cornell product (systolic: r=0.30/0.24, P=0.001; diastolic r=0.22/0.14, P<0.001) criteria of ECG-LVH. The correlation between home BP and ECG-LVH increased slightly with the number of home measurements, but even the mean of the initial two home BP measurements correlated equally well (systolic BP), or better (diastolic BP) with ECG-LVH than did clinic BP. In conclusion, home BP measurement allows us to obtain a large number of measurements that have a strong association with ECG-LVH. Our data support the application of home BP measurement in clinical practice.

Pulse wave velocity reference values in healthy adults aged 26-75 years.

The stiffening of arteries is associated with various cardiovascular diseases. Arterial stiffening can be studied utilizing arterial pulse wave velocity (PWV), but the absence of reliable reference values for PWV has limited its use in clinical practice. The aim of this study was to establish a range of reference values for PWV. PWV was examined by measuring the time difference of systolic pulse waves in arteries from the aortic arch to the popliteal artery using whole-body impedance cardiography (ICG). The study population consisted of 799 individuals (age range 25-76 years), 283 of whom had no evidence of cardiovascular disease, and a low burden of risk factors was selected to represent an apparently healthy population. In healthy study population, PWV was higher in males (8 x 9 +/- 1 x 8 m s(-1)) than females (8 x 1 +/- 2 x 0 m s(-1), P<0 x 001). Young males had lower PWV values than old males. Correspondingly, young females also had lower PWV values than old females. PWV was clearly associated with age, and PWV was higher in young and middle-aged males than in females. There was no statistically significant difference between old males and females in PWV. In conclusion, whole-body ICG provides a practical method for PWV measurement. Reference values can be useful in the clinical management of patients, especially in detecting early vascular disease or an increased risk of cardiovascular complications.

Food consumption and the incidence of type II diabetes mellitus.

OBJECTIVE: The consumption of different foods was studied for their ability to predict type II diabetes mellitus. DESIGN: The study design was a cohort study, based on the Finnish Mobile Clinic Health Examination Survey. SETTING: A total of 30 communities from different parts of Finland. SUBJECTS: A total of 4304 men and women, 40-69 y of age and free of diabetes at baseline in 1967-1972 and followed up for incidence of diabetes medication during 23 y (383 incident cases). RESULTS: Higher intakes of green vegetables, fruit and berries, oil and margarine, and poultry were found to predict a reduced risk of type II diabetes. The relative risks of developing type II diabetes between the extreme quartiles of the intakes were 0.69 (95% confidence interval (CI) = 0.50-0.93; P for trend (P) = 0.02) for green vegetables, 0.69 (CI = 0.51-0.92; P = 0.03) for fruit and berries, 0.71 (CI = 0.52-0.98; P = 0.01) for margarine and oil, and 0.71 (CI = 0.54-0.94; P = 0.01) for poultry. CONCLUSION: The results suggest that prevention of type II diabetes might be aided by consumption of certain foods that are rich in nutrients with hypothesized health benefits.

Hyperhomocystinemia: a risk factor or a consequence of coronary heart disease?

BACKGROUND: Mild hyperhomocystinemia has been suggested as an indicator of an increased risk of cardiovascular disease. OBJECTIVE: To examine whether serum homocysteine concentration is a predictor of coronary heart disease (CHD) events. METHODS: A case-control study, nested in a population-based cohort study was used. During a follow-up of 13 years, 166 major coronary events (death from CHD or nonfatal myocardial infarction) occurred in men with evidence of heart disease at baseline and 272 events in men without a history of heart disease. Two controls per case were selected by individual matching. RESULTS: Among men with known heart disease at baseline, the relative risk (95% confidence interval) of CHD events adjusted for age, smoking, hypertension, diabetes mellitus, serum cholesterol level, body mass index, and alcohol consumption was 2.23 (95% confidence interval, 1.03-4.85) in the highest serum homocysteine quintile compared with the lowest quintile. Among the men free of heart disease at baseline, the corresponding relative risk was 0.90 (95% confidence interval, 0.51-1.60). CONCLUSIONS: This prospective study does not support the hypothesis that a high concentration of serum homocysteine is a risk factor for coronary events in a population free of heart disease. However, it does suggest that mild hyperhomocystinemia predicts secondary coronary events in men with heart disease, possibly as a consequence of atherosclerotic changes.

The epidemiology of insulin-dependent diabetes mellitus (IDDM) in Finland and in northern Europe.

The incidence and prevalence of IDDM are high by international standards in all Nordic countries, and Finland has the highest incidence and prevalence figures of the disease in the world. During the period 1970-1980, the mean annual incidence (per 100,000) in 0-14-yr-old children was 28.6 in Finland, 22.7 in Sweden, 17.6 in Norway, and 14.0 in Denmark. The corresponding prevalence figures were: Finland 191, Sweden 148, Iceland 141, Norway 120, and Denmark 83. Thus, on a countrywide basis the incidence increased from south to north (and from west to east). However, within some of the Nordic countries (Finland, Norway, and Sweden) there were regional variations not compatible with the above "latitude rule." As in many studies from other countries, the following characteristics were observed in the IDDM epidemiology in children and adolescents: a steady rise of incidence throughout childhood until puberty, the peak occurring earlier in girls than in boys, a male excess in young children and adolescents, a seasonal variation, and a secular trend. The possible causes of the high incidence and prevalence are briefly discussed.

Nationwide survey of comorbidity, use, and costs of all medications in Finnish diabetic individuals.

OBJECTIVE: To investigate comorbidity and overall use and costs of medication for all Finnish individuals with diabetes treated with drugs compared with sex- and age-matched control subjects. RESEARCH DESIGN AND METHODS: According to a cross-sectional population study using national registries, 116,224 individuals purchased antidiabetic medications in Finland in 1995. The same number of nondiabetic individuals matched for sex, age, and area of residence were chosen as control subjects. Age at onset of diabetes was used as a criterion for distinguishing between type 1 and type 2 diabetes. The criterion could be applied in 74% of cases. A total of 16,955 individuals were defined as having type 1 diabetes, and 68,517 were defined as having type 2 diabetes. Comorbidity was determined by linkage with a national register including all individuals entitled to special reimbursement for drug treatment for a range of chronic diseases. Data on use and costs of all medications prescribed were obtained from drug purchase records. RESULTS: Cardiovascular diseases and uremia were, as expected, the chronic diseases most closely associated with diabetes. Use of almost all kinds of medication was significantly greater in individuals with type 1 and type 2 diabetes than in control subjects. The greatest differences were observed in relation to cardiovascular drugs and antibiotics. Unexpectedly low use of antiasthmatics was observed in individuals with both types of diabetes, low use of neuroleptics was observed in type 1 diabetic individuals, and low use of hormone replacement therapy was observed in women with type 2 diabetes. Total costs of medications for individuals with diabetes were 3.5 times greater than those for nondiabetic control subjects. The higher costs were mostly attributable to insulin therapy for individuals with type 1 diabetes. The higher costs for individuals with type 2 diabetes were related to the cost of medications other than antidiabetic medication. The possible selection bias in omitting diabetic individuals treated with diet only and individuals in whom diabetes type could not be determined must be considered in interpreting the results. CONCLUSIONS: Greater use by and costs of medications for individuals with diabetes than for nondiabetic individuals is related not only to antidiabetic treatment but also to all other kinds of medications. Although drug treatment and the prevalence of several chronic conditions were overall greater in individuals with diabetes versus other individuals, some exceptions merit further study

Hospital use among diabetic patients and the general population.

OBJECTIVE: This register-based linkage study compared hospital use among diabetic and nondiabetic populations. The study focused on overall use, use by disease categories, and inpatient care caused by complications. RESEARCH DESIGN AND METHODS: The patient data were derived from the Hospital Discharge Register and the Central Drug Register in Finland. All drug-treated diabetic patients and discharges of patients in a 3-year period were included in the study. Hospital use was measured by inpatient days, mean length of stay, and discharge rate. RESULTS: Among diabetic patients were eligible for drug reimbursement, 14.2% had at least one hospital stay because of diabetes in a year, while 50.7% had at least one hospital stay for any cause. Only 12.4% of the nondiabetic population was hospitalized annually. Patients with diabetes as the principal diagnosis consumed about 3% of all inpatient days; patients who had diabetes either as the principal or as a subsidiary diagnosis used 8.3%; and people who were eligible for antidiabetic drug reimbursement used 13.3% of total inpatient days. Among diabetic children, the risk for hospitalization was 6.5 times higher than among nondiabetic children. With advancing age, causes other than diabetes increasingly dominated hospitalization among diabetic patients. Inpatient days because of cardiovascular diseases were 1.6-18 times more common among diabetic patients than among nondiabetic patients, depending on gender and age-group. Diabetic patients used many more hospital inpatient days than did the nondiabetic population for a number of other disease categories that are usually not related to diabetes. CONCLUSIONS: Hospital use among diabetic patients is substantially greater than that among the nondiabetic population, mainly because of cardiovascular and microvascular complications, but also because of diseases unrelated to diabetes.

Glycemic control in patients with diabetes in Finland.

OBJECTIVE: To evaluate the quality of diabetes care at a national level in Finland, using level of glycemia as a determinant of success in treatment. RESEARCH DESIGN AND METHODS: Physicians and diabetes nurses in 76 randomly selected clinics (59 primary care units and 17 hospitals) evenly covering the whole of Finland were asked to fill in a questionnaire asking for data based on the 1993 medical records of a random sample of 50 diabetic patients from each center (total n = 3,800). HbAlc was used as an index of glycemic control. RESULTS: Information on 3,195 (84%) diabetic patients was received. HbAlc was measured in 67% of the patients in 1993. The mean HbAlc in the whole population was 8.6 +/- 1.9% (normal range 4-6%). Some 25% of patients had HbAlc < or = 7.3%, while 25% had HbAlc > or = 9.7%. The mean HbAlc was 8.8 +/- 1.9% in type 1 and 8.5 +/- 1.9% in type 2 diabetic patients. There was no sex difference in the HbAlc level in type 1 diabetic patients. However, male type 2 diabetic patients had better glycemic control than female patients (8.3 +/- 1.9 vs. 8.8 +/- 1.9%, P < 0.0001). The sex difference was independent of the type of therapy. The mean level of glycemic control was lowest among individuals with the shortest duration of diabetes. After 7-9 years after the diagnosis, there was no change in the mean level of glycemia. CONCLUSIONS: Average glycemic control is poor in a majority of the diabetic patients in Finland. Better treatment strategies and methods should be used to improve glycemic control and to reduce long-term complications.

Structure and costs of health care of diabetic patients in Finland.

OBJECTIVE: The aim of the present study was to examine both the structure, including modes of drug treatment, ambulatory care, and hospital inpatient care, and the costs of health care for drug-treated diabetic patients in Finland. RESEARCH DESIGN AND METHODS: The modes of drug treatment and ambulatory care were studied with the help of a questionnaire given to all diabetic patients obtaining their medication through pharmacies in Finland during a 7-week period in 1989. The questionnaire sought information on drug treatment, site of health care, and frequency of visits to physicians. Hospital inpatient care was evaluated by linking the patient data from the Hospital Discharge Register and the Central Drug Register. The direct costs of health care were calculated by using relevant average costs. RESULTS: A total of 30,266 questionnaires were returned, representing > 70% of all drug-treated diabetic patients receiving medication in the period studied. Of the diabetic patients, 63% were treated by oral medication only, 31% by insulin only, and 6% by a combination of insulin and oral agents. Of the patients in whom diabetes was diagnosed at > or = 30 years of age, 75% were treated at health centers, whereas > 60% of those in whom diabetes was diagnosed at < 30 years of age were treated at outpatient clinics. The mean annual frequency of visits was 4.0 for patients receiving insulin treatment and 3.3 for patients receiving treatment with oral medications. The diabetic patients used 1.5 million hospital inpatient days per year, which was 13% of the total inpatient days in Finland. Of the inpatient days, 20% were for diabetes as the principal cause, 52% for diabetes-related diseases, and 28% for causes unrelated to diabetes. The direct costs of the health care of drug-treated diabetic patients in 1989 were 5.8% of the total costs of health care in Finland and were three times higher than the average costs of care for nondiabetic individuals. The direct costs were divided into inpatient care (81%), medication (9%), ambulatory care (8%), and self-care equipment (2%). CONCLUSIONS: Hospital inpatient care is the major contributor to the excess of health care expenditures for diabetic patients.

Comparison of incidence of IDDM in childhood between Estonia and Finland, 1980-1988.

OBJECTIVE: To compare nationwide incidence of childhood insulin-dependent diabetes mellitus (IDDM) in children aged 0-14 yr between Estonia and Finland during 1980-1988. For Estonia, which has a population genetically and linguistically related to Finland, only limited information was available. Finland has the highest incidence of IDDM in the world. RESEARCH DESIGN AND METHODS: The registration of all new cases of IDDM in Estonia was conducted by the local district pediatricians who reported every newly diagnosed diabetic patient to the Republic Endocrinology Centre. Registration of all new cases of IDDM in Finland was based on the statistics of the Social Insurance Institution, which approves free-of-charge insulin treatment for diabetes. These data were validated with one or more additional data sources. The case ascertainment rate approached 100% in both countries. RESULTS: The average yearly incidence of IDDM standardized for age for the years 1980-1988 in Estonia was approximately 33% of that in Finland. Among males it was 11.3 (95% confidence interval [CI] 10.3-12.3) per 100,000 in Estonia and 35.1 (95% CI 33.4-36.9) per 100,000 in Finland, and among females 10.1 (95% CI 9.2-11.1) per 100,000 in Estonia and 30.4 (95% CI 28.8-32.1) per 100,000 in Finland. When the two periods 1980-1982 and 1986-1988 were compared, the age-standardized incidence in Estonia remained unchanged, whereas in Finland it increased approximately 20%. CONCLUSIONS: The data between two populations who are ethnically and linguistically similar and live geographically close but in a different environment, provides further evidence that both genetic and environmental factors are contributing to the risk of IDDM.

The unchanging incidence of hospitalization for diabetic nephropathy in a population-based cohort of IDDM patients in Finland.

OBJECTIVE: Finland has the highest documented incidence of childhood IDDM in the world, but the incidence of diabetic nephropathy in Finland is unknown. The aim of the present study was to determine the incidence of hospitalization for diabetic nephropathy in a population-based cohort of Finnish IDDM patients and to analyze the prognostic effect of sex, age at diagnosis, and calendar year of diagnosis of IDDM. RESEARCH DESIGN AND METHODS: We included all Finnish patients who had onset of IDDM before age 18 years, were diagnosed between January 1965 and December 1979 (n = 5,149), and were traced for hospitalizations between January 1970 and the end of December 1989 in the Hospital Discharge Register, using the unique personal identification code given to all Finnish citizens. The development of diabetic nephropathy was defined as the first hospitalization with a diagnosis of nephropathy (International Classification of Diseases-8th Revision [ICD-8] 250.04, or 9th Revision [ICD-9] 2503B/2503X). RESULTS: Among the 5,149 patients included, we identified 446 cases of diabetic nephropathy. The incidence of hospitalization for diabetic nephropathy was very low during the first 8 years of diabetes duration, and after that increased to a maximum of 1.6-2.0% per year. Female subjects developed nephropathy slightly earlier than male subjects, but the cumulative risk was independent of sex. Patients diagnosed at ages 5-14 years had the highest risk of hospitalization for diabetic nephropathy. We observed no effect of calendar year of diagnosis. CONCLUSIONS: We found a 20% cumulative incidence of hospitalization for diabetic nephropathy during a total 24 years of IDDM duration. This finding is compatible with the cumulative incidence of hospitalization for diabetic nephropathy found in other European populations. The incidence of hospitalization for diabetic nephropathy did not decrease during the 20-year observation period.