Atrial Fibrillation Burden in Young Patients With Congenital Heart Disease.

BACKGROUND: Patients with congenital heart disease (CHD) are assumed to be vulnerable to atrial fibrillation (AF) as a result of residual shunts, anomalous vessel anatomy, progressive valvulopathy, hypertension, and atrial scars from previous heart surgery. However, the risk of developing AF and the complications associated with AF in children and young adults with CHD have not been compared with those in control subjects. METHODS: Data from the Swedish Patient and Cause of Death registers were used to identify all patients with a diagnosis of CHD who were born from 1970 to 1993. Each patient with CHD was matched by birth year, sex, and county with 10 control subjects from the Total Population Register in Sweden. Follow-up data were collected until 2011. RESULTS: Among 21 982 patients (51.6% men) with CHD and 219 816 matched control subjects, 654 and 328 developed AF, respectively. The mean follow-up was 27 years. The risk of developing AF was 21.99 times higher (95% confidence interval, 19.26-25.12) in patients with CHD than control subjects. According to a hierarchical CHD classification, patients with conotruncal defects had the highest risk (hazard ratio, 84.27; 95% confidence interval, 56.86-124.89). At the age of 42 years, 8.3% of all patients with CHD had a recorded diagnosis of AF. Heart failure was the quantitatively most important complication in patients with CHD and AF, with a 10.7% (70 of 654) recorded diagnosis of heart failure. CONCLUSIONS: The risk of AF in children and young adults with CHD was 22 times higher than that in matched control subjects. Up to the age of 42 years, 1 of 12 patients with CHD had developed AF, and 1 of 10 patients with CHD with AF had developed heart failure. The patient groups with the most complex congenital defects carried the greatest risk of AF and could be considered for targeted monitoring.

The incidence of atrial fibrillation and the added value of thumb ECG for detecting new cases.

OBJECTIVES: To evaluate the incidence of atrial fibrillation (AF) as well as the value of thumb electrocardiography (ECG) for identification of paroxysmal AF in a Swedish cohort of middle-aged men from the general population. DESIGN: A population based random cohort of 798 men underwent screening at the age of 50 and re-examined at the age of 60 and 71 years. At the last examination, a thumb ECG recording was conducted for 2 weeks twice a day in 479 men from the original cohort. Registered hospital AF diagnoses were retrieved from the Swedish Patient Registry from 1993 to 2014. RESULTS: During a 21-year follow-up, 77 men (9.6%) were diagnosed with AF; of these men, 49.4% (38 of 77) had permanent AF. Fifteen of 479 (3.1%) patients had paroxysmal AF. Of those, seven had been previously diagnosed with paroxysmal AF through Patient Registry. The incidence of AF increased from 2.2 per 1000 years at risk at the age of 50-54 years to 9.3 per 1000 years at risk at the age 65-70 years. The prevalence of AF at the age of 71 years was increased from 7.1% to 9.9% using thumb ECG. CONCLUSIONS: In addition to medical history, patient register and 12-lead -ECG, the use of thumb ECG increased the number of detected paroxysmal AF by 21%.

Trends in out-of-hospital deaths due to coronary heart disease in Sweden (1991 to 2006).

BACKGROUND: Case fatality associated with a first coronary event is often underestimated when only those who survive to reach a hospital are considered. Few studies have examined long-term trends in case fatality associated with a major coronary event that occurs out of the hospital. METHODS AND RESULTS: Record linkage documented all case subjects 35 to 84 years of age in Sweden during 1991 to 2006 with a first major coronary event (out-of-hospital coronary death or hospitalization for acute myocardial infarction). Of the 384 597 cases identified, 111 319 (28.9%) died out of the hospital, and another 36 552 (9.5%) died in the hospital or within 28 days of hospitalization. From 1991 to 2006, out-of hospital deaths as a proportion of all major coronary events declined from 30.5% to 25.6% (adjusted mean annual decrease 2.2%, 95% confidence interval 2.1% to 2.4%), however, with a larger decline in 28-day case fatality in hospitalized cases (adjusted mean annual decrease 5.8%, 95% confidence interval 5.5% to 6.0%). As a result of the faster decline in in-hospital deaths, the relative contribution of out-of-hospital deaths to overall case fatality increased, particularly among younger individuals (eg, among those 35 to 54 years of age, no more than 10.8% of all deaths occurred in hospitalized cases during 2003-2006). Although female sex (odds ratio 0.85, 95% confidence interval 0.83 to 0.87) and older age (odds ratio 0.972, 95% confidence interval 0.971 to 0.974 per year) were associated with lower risk for initial out-of-hospital death, each successive calendar year was associated with increased risk (odds ratio 1.041, 95% confidence interval 1.038 to 1.044). CONCLUSIONS: The great majority of all fatal coronary events occur outside the hospital, and this proportion is increasing, particularly among younger individuals.

Intake of Lactobacillus plantarum reduces certain gastrointestinal symptoms during treatment with antibiotics.

GOALS: To examine if intake of Lactobacillus plantarum can prevent gastrointestinal side effects in antibiotic-treated patients. BACKGROUND: Diarrhea is a common side effect of treatment with antibiotics. Some studies indicate that the risk of antibiotic-associated diarrhea can be reduced by administration of certain probiotic microorganisms. STUDY: Patients treated for infections at a university hospital infectious diseases clinic were randomized to daily intake of either a fruit drink with L. plantarum 299v (10(10) colony forming units/d) or a placebo drink, until a week after termination of antibiotic treatment. Subjects recorded the number and consistency of stools as well as gastrointestinal symptoms until up to 3 weeks after last intake of test drink. Fecal samples were collected before the first intake of test drink and after termination of antibiotic therapy and analyzed for Clostridium difficile toxin. RESULTS: Clinical characteristics on admission were similar in the 2 groups. The overall risk of developing loose or watery stools was significantly lower among those receiving L. plantarum [odds ratio (OR), 0.69; 95% confidence interval (CI), 0.52-0.92; P=0.012], as was development of nausea (OR, 0.51; 95% CI, 0.30-0.85; P=0.0097). Diarrhea defined as > or =3 loose stools/24 h for > or =2 consecutive days was unaffected by the treatment (OR, 1.4; 95% CI, 0.33-6.0; P=0.86). No significant differences regarding carriage of toxin producing C. difficile were observed between the groups. CONCLUSIONS: Our results indicate that intake of L. plantarum could have a preventive effect on milder gastrointestinal symptoms during treatment with antibiotics.

Big men and atrial fibrillation: effects of body size and weight gain on risk of atrial fibrillation in men.

AIMS: Obesity is a recognized risk factor for atrial fibrillation (AF), partly because of the association between body mass index (BMI) and atrial volume. We aimed to determine whether other factors relating to body size were related to AF. METHODS AND RESULTS: Data were derived from a random population sample of 6903 men (mean age 51.5 years) who underwent a single midlife evaluation as part of the multifactor Swedish Primary Prevention Study. A total of 1253 men (18.2%) had a subsequent hospital discharge diagnosis (principal or secondary) of AF during a maximum follow-up of 34.3 years. Body surface area (BSA) at age 20 (calculated from recalled weight and measured height) was strongly related to subsequent AF (P < 0.0001), as were midlife BMI and weight gain from age 20 to midlife (P < 0.0001). In a Cox regression model which adjusted for midlife BMI, weight gain and other risk factors, hazard ratios (HR) [95% confidence intervals (CI)] for AF for the second, third, and fourth quartile of BSA at age 20, compared with the lowest quartile, were 1.47 (95% CI, 1.22-1.76), 1.66 (95% CI, 1.38-2.00), and 2.22 (95% CI, 1.82-2.70) (P for trend <0.0001). CONCLUSION: Large body size in youth, in an era when obesity was rare, as well as weight gain from age 20 to midlife, were both independently related to the development of AF. Given the current trends not only for obesity but also for height, a substantial increase in the incidence of AF is likely.

Impact of socioeconomic status on coronary artery calcification.

Background Low socioeconomic status is associated with an increased risk of coronary artery disease, but few studies have investigated the potential link between living in an area with a low versus a high socioeconomic status and coronary artery calcification, a marker of subclinical coronary artery disease. Design The design of this study was a cross-sectional study. Methods We evaluated 1067 participants with no history of coronary artery disease from the pilot phase of the Swedish CArdioPulmonary bioImage Study (SCAPIS). Men and women aged 50-64 years were recruited from three high-socioeconomic status ( n = 541) and three low-socioeconomic status ( n = 526) areas in the city of Gothenburg (550,000 inhabitants). The coronary artery calcification score was assessed with the Agatston method using computed tomography, with individuals classified into either no coronary calcification ( n = 625; mean age, 57 years) or any coronary artery calcification ( n = 442; mean age, 59 years (men, 68.5%)). Results Coronary artery calcification was present in 244 (46.3%) and 198 (36.6%) individuals from the low- and high-socioeconomic status areas, respectively. Participants from the low-socioeconomic status areas had a significantly higher risk factor burden. In a multivariable logistic regression model with adjustment for age, sex and cardiovascular risk factors, the odds for coronary artery calcification were not significantly higher among persons living in low-socioeconomic status areas (odds ratio = 1.18, 95% confidence interval = 0.87-1.60). Conclusion In this relatively small cross-sectional study, we observed an association between living in a low-socioeconomic status area and coronary artery calcification. However, this was mostly explained by higher levels of cardiovascular disease risk factors, indicating that the effect of socioeconomic status on the atherosclerotic process works through an increased burden of cardiovascular disease risk factors.

Ischemic heart disease in children and young adults with congenital heart disease in Sweden.

BACKGROUND: An increasing proportion of congenital heart disease (CoHD) patients survive to an age associated with increased risk of developing ischemic heart disease (IHD). The aim was to investigate the risk of developing IHD among children and young adults with CoHD. METHODS: Using the Swedish National Patient Register, we created a cohort of all CoHD patients born between January 1970 and December 1993. Ten controls matched for age, sex, county were randomly selected from the general population for each patient (n=219,816). Patients and controls were followed from birth until first IHD event, death, or December 31, 2011. RESULTS: We identified 21,982 patients with CoHD (51.6% men), mean follow-up was 26.4 (21.2-33.9) years. CoHD patients had 16.5 times higher risk of being hospitalized with or dying from IHD compared to controls (95% CI: 13.7-19.9), p<0.0001. Patients with conotruncal defects and severe nonconotruncal defects, had the highest IHD incidence rate (71.1 and 56.3 cases per 100,000 person-years, respectively, compared to 2.9 and 2.3 in controls). Hypertension and diabetes were less common among CoHD patients with IHD than among controls with IHD (hypertension 9.7% vs 19.7%, diabetes 1.8% vs 7.7% in CoHD patients and controls). Patients with aortic coarctation did not have a specific increase in the risk of developing IHD or acute myocardial infarction. CONCLUSIONS: In this large case-control cohort study, the relative risk of developing IHD was markedly higher in CoHD patients than in controls. However, the absolute risk was low in both groups.

Long-term risk factors for stroke: twenty-eight years of follow-up of 7457 middle-aged men in Göteborg, Sweden.

BACKGROUND AND PURPOSE: To estimate the predictive value of risk factors for stroke measured in midlife over follow-up extending through 28 years. METHODS: A cohort of 7457 men 47 to 55 years of age and free of stroke at baseline year 1970 were examined. Risk of stroke was analyzed for the entire period and for 0 to 15, 16 to 21, and 22 to 28 years of follow-up using age-adjusted and multiple Cox regression analyses. RESULTS: Age, diabetes, and high blood pressure were independently associated with increased risk of stroke for the entire 28 years and for each of the periods. Previous transient ischemic attacks, atrial fibrillation, history of chest pain, smoking, and psychological stress were independently related to stroke for the entire follow-up period and also during the first 1 or 2 successive periods. Family history of stroke or of coronary disease carried no independent prognostic information, nor did serum cholesterol. Elevated body mass index predicted stroke during the later part of the follow-up and so did (almost) low physical activity during leisure time, together with antihypertensive medication at baseline. CONCLUSIONS: High blood pressure and diabetes retain their importance as stroke risk factors also over an extended follow-up into old age. A family history of cardiovascular disease was not significantly related to outcome. Transient ischemic attacks, atrial fibrillation, stress, smoking, and a history of chest pain were associated with outcome only for the first or the first 2 periods. High body mass index and antihypertensive medication at baseline emerged as risk factors in the second and third decades.

Considerable disturbances of cardiovascular risk factors in women with diabetes and myocardial infarction.

OBJECTIVE: To investigate to which extent differences in cardiovascular risk factors explain the increased risk of myocardial infarction (MI) and complication rate in women with diabetes mellitus (DM). DESIGN: Case-control study. SUBJECTS: We compared women with diabetes and previous MI (n=29), diabetes but no MI (n=46), prior MI but no diabetes (n=64), and healthy controls (n=125). MEASUREMENTS: Smoking habits, physical activity, blood pressure (BP), body mass index (BMI), waist/hip ratio (WHR), serum lipids, plasma fibrinogen, and serum sex hormones. RESULTS: Despite the fact that diabetic women had similar BMI, those with a past MI, compared to diabetic women without MI, had significantly higher WHR (mean, 95% CI) [0.89 (0.87, 0.92) vs. 0.84 (0.81, 0.86) mmol/l, P=.001] and very high S-triglycerides [3.03 (2.23, 3.83) vs. 1.69, (1.39, 1.99) mmol/l, P=.001] and low HDL-cholesterol [1.09 (0.94, 1.24) vs. 1.56 (1.41, 1.71) mmol/l, P<.001], indicating pronounced metabolic disturbances. Women with MI but no diabetes had intermediate values for WHR, triglycerides, and HDL-cholesterol. Furthermore, women with diabetes and MI had significantly higher p-fibrinogen, were smokers, and lived a more sedentary life than the other women. Over half of all women with prior MI were on lipid-lowering therapy and tended to have nonsignificantly lower S-cholesterol than women without MI. CONCLUSIONS: Women with diabetes who have manifested an MI carry a very substantial cardiovascular risk factor burden, which probably explain their increased morbidity and mortality. In order to improve prognosis, studies targeted at investigating treatment modalities for these abnormalities are needed.

["Proportion of contact"--an alternative attempt to estimate health care needs]. / "Kontaktgrad"--alternativt ansats för att belysa behov av sjukvård.

The Swedish Health and Medical Care Act declares that health and medical care should be planned according to the needs of the population. Assessments of health care needs should begin with the total need of health care for any given population since the different forms of health care are dependent on each other. In Sweden, information on utilisation of care could estimate immediate short term health care needs. Individual self-perceived ill health is a reasonable basis for measures of health care needs, allowing for the fact that individuals often are in contact with several different forms of health care. Information regarding the 1.5 million individuals of the Västra Götaland Region and the associated utilisation of different forms of health care were collected for 2000 and 2001 . The proportion of contact is defined as the proportion of unique individuals from a specified geographical area who have been in contact with the health care system during a specified period of time. Each form of health care and the combinations thereof are regarded as a distinct category. The proportion of contact could be regarded as an estimate of the immediate overall self-perceived health care need and a reasonable measure for further studies on how to allocate resources.

Trends in stroke incidence after hospitalization for atrial fibrillation in Sweden 1987 to 2006.

BACKGROUND: To investigate recent trends in incidence of hemorrhagic and non-hemorrhagic strokes in patients with atrial fibrillation (AF). METHODS: The Swedish Hospital Discharge and Cause of Death Registries were linked to provide outcome data. RESULTS: 321,276 patients 35 to 84 years (56.5% male, mean age 71.5 years) free of prior stroke with a first AF diagnosis during 1987-2006 were included. Over 3 year follow-up 24,733 patients (7.7%) were diagnosed with ischemic stroke and 2292 (0.7%) with hemorrhagic stroke. The 3-year incidence of ischemic stroke decreased from 8.7% for patients diagnosed in 1987-1991 to 6.6% for those diagnosed in 2002 to 2006. The corresponding incidence of hemorrhagic stroke increased from 0.38% for patients diagnosed in 1987-1991 to 0.57% for those diagnosed in 2002 to 2006. Covariable-adjusted risk of ischemic stroke was significantly reduced (HR 0.65; 0.63-0.68) while risk of hemorrhagic stroke was significantly increased (HR 1.19; 1.05-1.36). Compared to the general population, total stroke risk decreased more among AF patients. CONCLUSION: We found a considerable decrease in risk of ischemic stroke in Sweden in patients without prior stroke and with a first hospital diagnosis of AF. There was an increased risk of hemorrhagic stroke, but because hemorrhagic stroke represented only a small proportion of all strokes, the overall risk of stroke declined.

Long-term prognosis after hospital admission for acute myocardial infarction from 1987 to 2006.

BACKGROUND: Recent population-based estimates for long-term cardiovascular disease (CVD) mortality after hospitalization for a first acute myocardial infarction (AMI) are not well established. METHODS: Data from the Swedish hospital discharge and death registries were used to record all first-ever hospital admissions in patients (n=348,772) 35-84 years with AMI from 1987 to 2006 and subsequent all-cause and CVD case fatality during up to 5 years. RESULTS: During the 20-year period, 28-day case fatality was reduced by almost two thirds in patients aged <75 years. For cases with a first AMI 1999-2002 long-term case fatality for men surviving the first 28 days and <55 years was 10.3/1000 person years, with rates of 23.6, 58.0 and 137.0 for men aged 55-64, 65-74 and 75-84 years. Corresponding figures for women were 10.5, 24.3, 51.8, 124.1 deaths/1000 years. In 1999-2002 estimated long-term risk of fatal CVD (based on survival until 2007) for men below 55 years was 6.1/1000 years, and 13.8, 34.6, 92.9 for men aged 55-64, 65-74, and 75-84 years, respectively. Corresponding figures for women were 4.8, 11.9, 30.1, 86.2/1000 years. The total reduction in CVD case fatality was two thirds among patients aged <55 and approximately one third among those aged 75-84. CONCLUSIONS: Long-term case fatality after hospitalization for AMI decreased markedly from 1987 to 2006, particularly with respect to CVD mortality and in younger patients. However, because of a steep increase in case fatality with age and a large proportion of older patients, long-term prognosis overall still remains poor.

Differences between coronary disease and stroke in incidence, case fatality, and risk factors, but few differences in risk factors for fatal and non-fatal events.

AIMS: To compare incidence and mortality of coronary and stroke events, and risk factors for non-fatal and fatal events, respectively. METHODS AND RESULTS: Incidence and mortality were compared in all coronary (n=559 341) and stroke (n=530 689) events in Sweden from 1987 to 2001. Data from 28 years of follow-up of a random sample of 7400 men aged 47-55 and free of disease at baseline were used to compare risk factors. Incidence and 28 days of case fatality were considerably higher for coronary disease than for stroke, especially for men. Incidence of coronary disease decreased, especially for men (P=0.0001 for both sexes), and mortality declined for both men and women during 1987-2001 (P=0.0001 for both sexes). Stroke incidence declined slightly (P=0.0001 for both sexes), and there was a decline of mortality (P=0.0001 for both sexes). Out-of-hospital mortality during the first 28 days was higher than in-hospital mortality for coronary events, whereas for stroke, in-hospital mortality was higher (in men) or the same (in women) as out-of-hospital mortality. High serum cholesterol was a strong risk factor for coronary events, but not for stroke. High blood pressure was a stronger risk factor for stroke. About 50% of men with both stroke and coronary disease died from coronary disease. CONCLUSION: Several differences regarding incidence, mortality, prognosis, and risk factors for stroke and coronary disease point towards different pathologies.

High lipid levels and coronary disease in women in Göteborg--outcome and secular trends: a prospective 19 year follow-up in the BEDA*study.

AIMS: To provide contemporary data on the effect of high cholesterol and high triglycerides on the risk of coronary heart disease (CHD) and mortality in Swedish women and to describe secular trends with respect to serum lipids, body mass index (BMI) and smoking in the source population. METHODS: We followed 1372 women aged 39-64 years and without prior cardiovascular disease from 1980 to 1999 through record-linkage with the Swedish hospital discharge and cause-specific death registers. Risk factor measurements were done at baseline. Every fifth year between 1980 and 1995 coronary risk factors were assessed in independent samples of the source population. RESULTS: In multivariate analyses, a 1 mmol increase in cholesterol was associated with a 51% increased risk of myocardial infarction (MI) and/or revascularisation (MI; p<0.0001) and a 30% increased risk of being hospitalised for CHD (p<0.0004). Women with cholesterol, 7-7.9 mmol/l, had a threefold risk of MI (HR 3.44 (1.63-7.23)) and hazard ratios in the highest cholesterol category, > or =8 mmol/l, was 4.49 (1.92-10.50) as compared to women with cholesterol below 6 mmol/l. A 1 mmol increase in triglycerides was associated with a 49% increased risk of MI (p=0.002) and a 45% increased risk of being hospitalised for CHD (p=0.001) after adjustment for major coronary risk factors. A moderate increase in triglycerides, 1.0-1.5 mmol/l, conferred no significant increase in risk of coronary events as compared to below 1.0 mmol/l. Women with high triglycerides, 1.5-1.9 mmol/l, had a doubled risk of MI (HR 2.55 (1.20-5.42)) and hazard ratios in the highest triglyceride category, > or =2.0 mmol/l, was 3.35 (1.48-7.60). Both high cholesterol and high triglycerides predicted mortality but the magnitude was smaller than for coronary events. During the study period the proportion of women with low cholesterol profile, below 6.0 mmol/l, increased on average from 49 to 68% and the proportion of women with low triglyceride levels, below 1.0 mmol/l, decreased from 59 to 36% in the source population. A modest increase in BMI was noted. CONCLUSIONS: Both high fasting cholesterol and high fasting triglycerides strongly predicted coronary events in middle-aged Swedish women. The favourable decline in cholesterol levels and smoking rates during the study period was offset by a marked increase in triglyceride levels. The findings suggest that interventional strategies directed to correct abnormalities in the triglyceride metabolism may be specifically warranted in women.

Body mass index, coronary heart disease and stroke in Swedish women. A prospective 19-year follow-up in the BEDA study.

BACKGROUND: Although obesity is an important determinant of an unfavourable risk factor pattern reported associations between cardiovascular disease and obesity in women have been remarkably inconsistent. DESIGN: Longitudinal observational population study. METHODS: 1408 Göteborg women without prior cardiovascular disease aged 39 to 65 years at baseline were examined with respect to cardiovascular risk factors, including body mass index (BMI), in 1979 to 1981. Quartiles of BMI were formed of <22 (reference), 22 to 24, 24 to 27, and >27 kg/m(-2). Follow-up was conducted by use of the Swedish patient and cause-specific death registers. RESULTS: All trends with respect to incident coronary heart disease (CHD--myocardial infarction or revascularization), stroke and all cardiovascular disease were positive and significant (P<0.05). No significant increase in risk was noted in women with BMI 22-24, compared with women below 22. After adjustment for smoking, women with BMI 24 to 27 had a doubled risk of CHD [hazard ratio(HR) 2.41 (1.06-5.50)] and of any cardiovascular disease [HR 1.89 (1.05-3.37)] whereas the increase in stroke risk was non-significant [HR 1.80 (0.81-4.01)]. Hazard ratios in the heaviest women, with BMI >27, were 3.75 (1.68-8.37) for CHD, 2.84 (1.32-6.12) for stroke, and 2.98 (1.70-5.21) for any cardiovascular disease, after adjustment for smoking. After further adjustment for other cardiovascular risk factors, all trends became non-significant. However, women with BMI >27 still displayed a statistically independent association with respect to coronary disease [adjusted HR 2.67 (1.10-6.47)] and all cardiovascular disease [HR 2.23 (1.23-4.04)], but not stroke [HR 2.08 (0.94-4.61)]. CONCLUSION: The influence of BMI on cardiovascular disease in women may be greater than previously thought and, although to a great extent explained by the influence of obesity on other risk factors, associated with adverse outcomes already at moderately increased body weight.

Insulin-like growth factor I levels in healthy adults.

Insulin-like growth factor I (IGF-I) levels mainly reflect secretion of growth hormone (GH) in the body. The aims of this study were to compare different IGF-I assay methods in healthy individuals, test the reliability of the methods and discuss the utility of IGF-I measurement in adults. The Nichols Institute Diagnostics radioimmunoassay was used to evaluate IGF-I in two random population samples of men and women (aged 25-64 years, n = 392) taken 10 years apart, in 1985 and 1995. This method for IGF-I testing was also compared with an immunoradiometric assay (IRMA) method in 387 men and women participating in the World Health Organization MONICA (MONItoring of trends and determinants for CArdiovascular diseases) Project, Goteborg, Sweden, in 1995. Serum IGF-I decreased with increasing age in both men and women. IGF-I was higher in young women compared with young men in both cohorts, while the opposite was found in the highest age group. Age-adjusted significant correlations were found between IGF-I and smoking, fibrinogen, coffee consumption, lipoprotein (a), osteocalcin and IGF-binding protein 3. The two cohorts showed similar mean IGF-I concentrations irrespective of method. The correlation between the Nichols and the IRMA methods was high: r = 0.93 (p < 0.0001). Based on this and previous studies, population-based IGF-I measurements are robust irrespective of which commercially available method of assay is used. IGF-I levels can be used in diagnosing acromegaly as well as providing target values. IGF-I assay can be used as a complement to stimulation testing in the diagnosis of GH deficiency, and as a tool for GH dose titration.