Jan Stålhammar

Prevalence and incidence of Type 2 diabetes and its complications 1996-2003-estimates from a Swedish population-based study

Aims  To determine the prevalence and incidence of Type 2 diabetes and its complications in Uppsala county, Sweden between 1996 and 2003.

Effects of losartan vs candesartan in reducing cardiovascular events in the primary treatment of hypertension

Although angiotensin receptor blockers have different receptor binding properties no comparative studies with cardiovascular disease (CVD) end points have been performed within this class of drugs. The aim of this study was to test the hypothesis that there are blood pressure independent CVD-risk differences between losartan and candesartan treatment in patients with hypertension without known CVD. Seventy-two primary care centres in Sweden were screened for patients who had been prescribed losartan or candesartan between the years 1999 and 2007. Among the 24 943 eligible patients, 14 100 patients were diagnosed with hypertension and prescribed losartan (n=6771) or candesartan (n=7329). Patients were linked to Swedish national hospitalizations and death cause register. There was no difference in blood pressure reduction when comparing the losartan and candesartan groups during follow-up. Compared with the losartan group, the candesartan group had a lower adjusted hazard ratio for total CVD (0.86, 95% confidence interval (CI) 0.77–0.96, P=0.0062), heart failure (0.64, 95% CI 0.50–0.82, P=0.0004), cardiac arrhythmias (0.80, 95% CI 0.65–0.92, P=0.0330), and peripheral artery disease (0.61, 95% CI 0.41–0.91, P=0.0140). No difference in blood pressure reduction was observed suggesting that other mechanisms related to different pharmacological properties of the drugs may explain the divergent clinical outcomes.

Resource use and costs of type 2 diabetes in Sweden – estimates from population-based register data

Aims:  To examine medical resource use of Swedish patients with type 2 diabetes during 2000–2004 and to estimate annual costs of care.

Time to insulin treatment and factors associated with insulin prescription in Swedish patients with type 2 diabetes

AIMS The purpose of this study was to investigate the time between the start of OAD treatment and the initiation of insulin therapy and to identify the factors associated with insulin prescription among Swedish patients with type 2 diabetes in Uppsala County. METHODS Retrospective, population-based, primary-care data gathered within the Swedish RECAP-DM study were used to identify type 2 diabetic patients who initiated OAD treatment. A Kaplan-Meier survival estimate for time to initiation of insulin therapy was generated and factors associated with insulin prescription were tested using a Cox proportional-hazards model. RESULTS Within 6 years of starting OAD treatment, an estimated 25% of Swedish patients with type 2 diabetes will be prescribed insulin (95% CI: 0.23-0.26) and, within 10 years, this figure will rise to 42% (95% CI: 0.39-0.45). The probability of insulin prescription was increased in patients aged less than 65 years (HR=1.24, 95% CI: 1.03-1.50) and in those who initiated OAD treatment with more than one agent (HR=2.71, 95% CI: 2.15-3.43). HbA(1c) at the time of starting OAD treatment was also related to the probability of insulin prescription (HR=1.20, 95% CI: 1.146-1.25). CONCLUSION Many type 2 diabetic patients who begin treatment with an OAD will eventually be prescribed insulin. Age, disease severity and the type of prior treatment may affect the rate of the transition.

Automated data extraction—A feasible way to construct patient registers of primary care utilization

Abstract Introduction. Electronic medical records (EMRs) enable analysis of health care data by using data mining techniques to build research databases. Though the reliability of the data extraction process is crucial for the credibility of the final analysis, there are few published validations of this process. In this paper we validate the performance of an automated data mining tool on EMR in a primary care setting. Methods. The Pygargus Customized eXtraction Program (CXP) was programmed to find and then extract data from patients meeting criteria for type 2 diabetes mellitus (T2DM) at one primary health care clinic (PHC). The ability of CXP to extract relevant cases was assessed by comparing cases extracted by an EMR integrated search engine. The concordance of extracted data with the original EMR source was manually controlled. Results. Prevalence of T2DM was 4.0%, which correspond well to previous estimations. By searching for drug prescriptions, diagnosis codes, and laboratory values, 38%, 53%, and 91% of relevant cases were found, respectively. The sensitivity of CXP regarding extraction of relevant cases was 100%. The specificity was 99.9% due to 12 non-T2DM cases extracted. The congruity at single-item level was 99.6%. The 13 incorrect data items were all located in the same structural module. Conclusion. The CXP is a reliable and accurate data mining tool to extract selective data from EMR.

Association between achieving treatment goals for lipid-lowering and cardiovascular events in real clinical practice

Background There is substantial evidence that treatment with lipid-lowering agents can decrease cardiovascular morbidity and total mortality in patients with elevated serum lipid values and/or prior ischaemic heart disease. However, only a minority of these high-risk patients are believed to receive treatment, and among those who do receive pharmaceutical treatment the majority do not reach the therapeutic goal. Our goal was to investigate if this translates to a higher risk of cardiovascular events in real clinical practice. Design A retrospective cohort study using linkage of electronic medical records, the Swedish national inpatient registry and cause of death registry was performed, enrolling a total of 4976 patients who received treatment with a lipid-lowering agent at any time between 1 January 1993 and 1 December 2001. Methods Cox proportional hazards regression was used to evaluate the impact of goal attainment along with potential confounding factors. Results Patients who reached treatment goals were 24% less likely to suffer a cardiovascular event (relative risk: 0.76, 95% confidence interval: 0.60–0.96) than patients who did not reach treatment goals. A substantial proportion of patients treated with lipid-lowering agents do not achieve the treatment goals. Conclusions Failure to reach treatment goals translates into a higher risk of cardiovascular events, and it is thus of importance to ensure that patients reach goals.

Metabolic Control in Diabetic Subjects in Three Swedish Areas With High, Medium, and Low Sales of Antidiabetic Drugs

Objective The relationship between use of antidiabetic drugs and metabolic control was studied in Swedish diabetic populations in areas with high (Gotland), medium (Tierp), and low (Skellefteå) sales of antidiabetic drugs. Research Design and Methods The study population consisted of 405 drug-treated diabetic subjects aged 50–74 yr. In all three areas, glyburide comprised ∼75% of the oral treatment. Results In accordance with sales, Gotland was found to be a heavy-use area, characterized by a high prevalence of insulin treatment (43%), combination therapy with sulfonylureas and biguanide (28%), and high prescribed daily doses (PDDs) of glyburide (15.5 ± 0.8 mg) compared with other areas. In Skellefteå, 38% were on insulin, 4% were on combination therapy, and the PDD of glyburide was 7.1 ± 0.6 mg. In Tierp, 27% were on insulin, 26% were on combination therapy, and the PDD of glyburide was 11.4 ± 0.7 mg. In Gotland, both men and women had significantly lower HbA1c levels, regardless of treatment mode, and a tendency to be more overweight compared with the area with the least pharmacological intensity (Skellefteå). Conclusions In the three diabetic populations, good metabolic control, defined as an HbA1c level of < 7% and acceptable weight control (body mass index < 27 for men and < 25 for women), was achieved among only 16% in Gotland, 17% in Skellefteå, and 12% in Tierp.

Cost of care for patients treated with lipid-lowering drugs.

AbstractObjective: To investigate the relationship between attainment of treatment goals with lipid-lowering therapy and healthcare costs. Participants: 9789 patients who received treatment with a lipid-lowering agent at any time between 1 January 1993 and 14 April 2003. Design and methods: A cohort study using linkage of patient medical records from 29 Swedish primary care centres and the Swedish national inpatient register. The primary outcomes of interest were the total costs of medical care and costs of cardiovascular-related inpatient care during the year before treatment initiation and during years 1, 2 and 3 of treatment. The cost data were analysed with a two-part randomeffects regression model. Results: Of the 9789 patients identified in the database for the study, 6316 had at least one cholesterol measurement during the year after the index prescription and were included in the analysis. 37% of the patients attained the goal of low-density lipoprotein cholesterol <3.0 mmol/L and total cholesterol <5.0 mmol/L. Patients who attained treatment goal had 44% higher pre-treatment costs of care. During the first year of treatment, patients who attained treatment goal had 28% higher costs of care. After the first year, costs for goal-attaining patients were 17% higher. However, the cost of cardiovascular-related inpatient care in patients attaining cholesterol treatment goal was twice as high as in patients not achieving goal before treatment start and 40% lower 2–3 years after treatment start. Conclusion: Patients reaching target cholesterol levels showed a trend of cost reductions over time, whereas no such trend could be found for patients not reaching goal levels. Reductions in costs were substantial for cardiovascular-related inpatient care for patients attaining cholesterol goals compared with patients not attaining cholesterol goals.

The impact of acute myocardial infarction and stroke on health care costs in patients with type 2 diabetes in Sweden

Background Estimates of the economic impact of cardiovascular events in patients with type 2 diabetes are scarce. The aim of this study was to determine the health care costs associated with acute myocardial infarction (AMI) and stroke in patients with type 2 diabetes in Sweden. Design Population-based open cohort study of 9941 patients with type 2 diabetes retrospectively identified in primary care records at 26 centres in Uppsala County. Methods Episodes of AMI and stroke suffered by study patients were tracked in the Swedish National Inpatient Register. Annual per patient costs of health care were computed for the years 2000-2004 using register data covering inpatient care, outpatient hospital care, primary care and drugs. Panel data regression was applied to determine the impact of suffering a first or repeat AMI or stroke on health care costs during the year of the event and in subsequent years. Results Total health care costs of patients suffering a first AMI/stroke increased by 4.1/6.5 during the year of the event [95% confidence interval (CI): 3.1-5.4/4.9-8.5] and by 1.1/1.4 during subsequent years (95% CI: 1.0-1.3/1.2-1.6), controlling for age, sex, the event of amputation and presence of renal failure, heart failure and diabetic eye disease. Total health care costs of patients suffering a first or repeat AMI/stroke increased by 4.1/6.4 during the year of an event (95% CI: 3.2-5.2/5.0-8.1) but were not significantly higher during subsequent years. Conclusion Estimates of the costs related to major cardiovascular complications of type 2 diabetes are critical input to economic evaluations.

Resource Utilization and Cost of Heart Failure associated with Reduced Ejection Fraction in Swedish Patients

Abstract Aim: The purpose of this study was to assess healthcare utilization and costs for heart failure patients with reduced ejection fraction (HF-REF) in Sweden. Methods and Results: This was a retrospective, population-based cohort study of patients diagnosed with HF-REF during a period of 18 months at 31 primary care centers in Uppsala County, Sweden. Data was obtained from computerized records from these centers, the Swedish Patient Registry, the Swedish Prescription Registry, the Cause of Death Registry, and a local echocardiography registry maintained by the Department of Physiology, Uppsala University Hospital. Main outcome measures were cardiovascular and heart-failure-related hospitalizations, outpatient visits, medication utilization, mortality (all-cause, cardiovascular, and heart-failure), and healthcare costs for HF-REF patients. During the index period, 252 heart failure patients had a left ventricular ejection fraction measurement ≤40% and were categorized as having HF-REF. More than half of the patients had ≥1 cardiovascular or heart failure-related hospitalization. On average, patients had >2 such hospitalizations annually. They also averaged ∼1 cardiovascular or heart-failure-related outpatient visit per year. All-cause mortality was high: 15.9% patients died within 1 year after the index date. The mean annual cost per patient for heart-failure-related hospitalizations was SEK 72,613 (EUR 7610). In contrast, annual prescription costs were low, on average 3% of total cost (SEK 3503, EUR 367 per patient) Limitations: The main limitations of this study include a short follow-up time and small sample size. Also, certain data were missing, such as echocardiograms (available for only 28% of patients), and information on patients’ New York Heart Association (NYHA) functional class, validity period for prescriptions or the units of medication prescribed, and medication dosing. Furthermore, the overall mortality could have been under-estimated, as only the primary cause of death was included in the analysis. Conclusions: The main burden associated with HF-REF is related to hospitalizations for heart-failure events. Effective treatment options that decrease hospitalization rates could reduce patients’ suffering and potentially offer considerable cost savings.