Iron, hemochromatosis genotypes, and risk of infections: a cohort study of 142 188 general population individuals.

ABSTRACT: It is unclear whether risk of infection is increased in individuals with hereditary hemochromatosis and in individuals with low or high plasma iron, transferrin saturation, or ferritin. Therefore, we tested whether high and low iron, transferrin saturation, and ferritin are associated with risk of infections observationally and genetically through HFE genotypes. We studied 142 188 Danish general population individuals. Iron, transferrin saturation, and ferritin were measured in 136 656, 136 599, and 38 020 individuals, respectively. HFE was genotyped for C282Y and H63D in 132 542 individuals. Median follow-up after study enrollment was 8 years (range, 0-38) for hospital and emergency room admissions with infections (n = 20 394) using the National Patient Register, covering all Danish hospitals. Hazard ratios for any infection were 1.20 (95% confidence interval [CI], 1.12-1.28) and 1.14 (95% CI, 1.07-1.22) in individuals with plasma iron ≤5th or ≥95th percentile compared with individuals with iron from 26th to 74th percentiles. Findings for transferrin saturation were similar, whereas infection risk was not increased in individuals with ferritin ≤5th or ≥95th percentile. Hazard ratios in C282Y homozygotes vs noncarriers were 1.40 (95% CI, 1.16-1.68) for any infection, 1.69 (95% CI, 1.05-2.73) for sepsis, and 2.34 (95% CI, 1.41-3.90) for death from infectious disease. Risk of infection was increased in C282Y homozygotes with normal plasma iron, transferrin saturation, or ferritin, and in C282Y homozygotes without liver disease, diabetes, and/or heart failure. In summary, low and high plasma iron and transferrin saturation were independently associated with increased infection risk. C282Y homozygotes had increased risk of any infection, sepsis, and death from infections. Even C282Y homozygotes with normal iron, transferrin saturation, or ferritin, not currently recommended for genotyping, had increased infection risk.

Type-2 inflammation and lung function decline in chronic airway disease in the general population.

BACKGROUND: It is unclear if type-2 inflammation is associated with accelerated lung function decline in individuals with asthma and chronic obstructive pulmonary disease (COPD). We tested the hypothesis that type-2 inflammation indicated by elevated blood eosinophils (BE) and fraction of exhaled nitric oxide (FeNO) is associated with accelerated lung function decline in the general population. METHODS: We included adults from the Copenhagen General Population Study with measurements of BE (N=15 605) and FeNO (N=2583) from a follow-up examination and assessed forced expiratory volume in 1 s (FEV1) decline in the preceding 10 years. Based on pre- and post-bronchodilator lung function, smoking history and asthma at follow-up examination, participants were assigned as not having airway disease, asthma with full reversibility (AR), asthma with persistent obstruction (APO), COPD, and not classifiable airflow limitation (NAL). RESULTS: FEV1 decline in mL/year increased with 1.0 (95% CI 0.6 to 1.4, p<0.0001) per 100 cells/µL higher BE and with 3.2 (95% CI 2.0 to 4.5, p<0.0001) per 10 ppb higher FeNO. Adjusted FEV1 decline in mL/year was 18 (95% CI 17 to 20) in those with BE<300 cells/µL and FeNO<20 ppb, 22 (19-25) in BE≥300 cells/µL or FeNO≥20 ppb, and 27 (21-33) in those with BE≥300 cells/µL and FeNO≥20 ppb (p for trend<0.0001). Corresponding FEV1 declines were 24 (19-29), 33 (25-40) and 44 (31-56) in AR (0.002), 26 (14-37), 36 (12-60) and 56 (24-89) in APO (0.07), 32 (27-36), 31 (24-38) and 44 (24-65) in COPD (0.46), and 27 (21-33), 35 (26-45), and 37 (25-49) in NAL (0.10), respectively. CONCLUSIONS: Type-2 inflammation indicated by elevated BE and FeNO is associated with accelerated FEV1 decline in individuals with chronic airway disease in the general population, and this association was most pronounced in an asthma-like phenotype.

Subclinical Coronary Atherosclerosis and Risk for Myocardial Infarction in a Danish Cohort : A Prospective Observational Cohort Study.

BACKGROUND: Coronary atherosclerosis may develop at an early age and remain latent for many years. OBJECTIVE: To define characteristics of subclinical coronary atherosclerosis associated with the development of myocardial infarction. DESIGN: Prospective observational cohort study. SETTING: Copenhagen General Population Study, Denmark. PARTICIPANTS: 9533 asymptomatic persons aged 40 years or older without known ischemic heart disease. MEASUREMENTS: Subclinical coronary atherosclerosis was assessed with coronary computed tomography angiography conducted blinded to treatment and outcomes. Coronary atherosclerosis was characterized according to luminal obstruction (nonobstructive or obstructive [≥50% luminal stenosis]) and extent (nonextensive or extensive [one third or more of the coronary tree]). The primary outcome was myocardial infarction, and the secondary outcome was a composite of death or myocardial infarction. RESULTS: A total of 5114 (54%) persons had no subclinical coronary atherosclerosis, 3483 (36%) had nonobstructive disease, and 936 (10%) had obstructive disease. Within a median follow-up of 3.5 years (range, 0.1 to 8.9 years), 193 persons died and 71 had myocardial infarction. The risk for myocardial infarction was increased in persons with obstructive (adjusted relative risk, 9.19 [95% CI, 4.49 to 18.11]) and extensive (7.65 [CI, 3.53 to 16.57]) disease. The highest risk for myocardial infarction was noted in persons with obstructive-extensive subclinical coronary atherosclerosis (adjusted relative risk, 12.48 [CI, 5.50 to 28.12]) or obstructive-nonextensive (adjusted relative risk, 8.28 [CI, 3.75 to 18.32]). The risk for the composite end point of death or myocardial infarction was increased in persons with extensive disease, regardless of degree of obstruction-for example, nonobstructive-extensive (adjusted relative risk, 2.70 [CI, 1.72 to 4.25]) and obstructive-extensive (adjusted relative risk, 3.15 [CI, 2.05 to 4.83]). LIMITATION: Mostly White persons were studied. CONCLUSION: In asymptomatic persons, subclinical, obstructive coronary atherosclerosis is associated with a more than 8-fold elevated risk for myocardial infarction. PRIMARY FUNDING SOURCE: AP Møller og Hustru Chastine Mc-Kinney Møllers Fond.

Low levels of small HDL particles predict but do not influence risk of sepsis.

BACKGROUND: Low levels of high-density lipoprotein (HDL) cholesterol have been associated with higher rates and severity of infection. Alterations in inflammatory mediators and infection are associated with alterations in HDL cholesterol. It is unknown whether the association between HDL and infection is present for all particle sizes, and whether the observed associations are confounded by IL-6 signalling. METHODS: In the UK Biobank, ~ 270,000 individuals have data on HDL subclasses derived from nuclear magnetic resonance analysis. We estimated the association of particle count of total HDL and HDL subclasses (small, medium, large, and extra-large HDL) with sepsis, sepsis-related death, and critical care admission in a Cox regression model. We subsequently utilised genetic data from UK Biobank and FinnGen to perform Mendelian randomisation (MR) of each HDL subclass and sepsis to test for a causal relationship. Finally, we explored the role of IL-6 signalling as a potential causal driver of changes in HDL subclasses. RESULTS: In observational analyses, higher particle count of small HDL was associated with protection from sepsis (Hazard ratio, HR 0.80; 95% CI 0.74-0.86, p = 4 × 10-9 comparing Quartile 4, highest quartile of HDL to Quartile 1, lowest quartile of HDL), sepsis-related death (HR 0.80; 95% CI 0.74-0.86, p = 2 × 10-4), and critical care admission with sepsis (HR 0.72 95% CI 0.60-0.85, p = 2 × 10-4). Parallel associations with other HDL subclasses were likely driven by changes in the small HDL compartment. MR analyses did not strongly support causality of small HDL particle count on sepsis incidence (Odds ratio, OR 0.98; 95% CI 0.89-1.07, p = 0.6) or death (OR 0.94, 95% CI 0.75-1.17, p = 0.56), although the estimate on critical care admission with sepsis supported protection (OR 0.73, 95% CI 0.57-0.95, p = 0.02). Bidirectional MR analyses suggested that increased IL-6 signalling was associated with reductions in both small (beta on small HDL particle count - 0.16, 95% CI - 0.10 to - 0.21 per natural log change in SD-scaled CRP, p = 9 × 10-8).and total HDL particle count (beta - 0.13, 95% CI - 0.09 to - 0.17, p = 7 × 10-10), but that the reverse effect of HDL on IL-6 signalling was largely null. CONCLUSIONS: Low number of small HDL particles are associated with increased hazard of sepsis, sepsis-related death, and sepsis-related critical care admission. However, genetic analyses did not strongly support this as causal. Instead, we demonstrate that increased IL-6 signalling, which is known to alter infection risk, could confound associations with reduced HDL particle count, and suggest this may explain part of the observed association between (small) HDL particle count and sepsis.

Genetic variants in the adenosine triphosphate-binding cassette transporter A1 and risk of age-related macular degeneration.

Genetic variants in ABCA1 are associated with higher concentrations of high-density lipoprotein (HDL) cholesterol. Higher HDL cholesterol concentrations are observationally and genetically associated with higher risk of age-related macular degeneration (AMD). However, whether amino acid-changing genetic variants in ABCA1 associated with high HDL cholesterol concentrations confer a higher risk of AMD in the general population is currently unknown. We tested this hypothesis. The study included 80,972 individuals (1,370 AMD cases) from the Copenhagen General Population Study (CGPS) and 9,584 individuals (142 AMD cases) from the Copenhagen City Heart Study (CCHS) with 10 to 18 years of follow-up. We created an HDL cholesterol weighted allele score based on amino acid-changing ABCA1 variants with a minor allele frequency above 0.001 and divided it into tertiles. The study included 55% women. Mean age was 58 years. The ABCA1 allele score for the third versus the first tertile was associated with HRs (95% confidence intervals (CIs)) of 1.30 (1.14-1.49) for all-cause AMD, 1.26 (1.06-1.50) for nonneovascular AMD, and 1.31 (1.12-1.53) for neovascular AMD in a multivariable adjusted model. On a continuous scale, higher concentrations of genetically determined HDL cholesterol were associated with higher risk of all-cause AMD, nonneovascular AMD, and neovascular AMD in an age- and sex adjusted model and in a multivariable adjusted model. In conclusion, amino acid-changing genetic variants in ABCA1 associated with higher HDL cholesterol concentrations were also associated with higher risk of AMD, suggesting a role for ABCA1 in AMD pathogenesis.

Elevated remnant cholesterol increases the risk of peripheral artery disease, myocardial infarction, and ischaemic stroke: a cohort-based study.

AIMS: The atherogenic potential of cholesterol in triglyceride-rich lipoproteins, also called remnant cholesterol, is being increasingly acknowledged. Elevated remnant cholesterol is associated with increased risk of myocardial infarction and ischaemic stroke. We tested the hypothesis that elevated remnant cholesterol is also associated with increased risk of peripheral artery disease (PAD). METHODS AND RESULTS: We studied 106 937 individuals from the Copenhagen General Population Study recruited in 2003-15. During up to 15 years of follow-up, 1586 were diagnosed with PAD, 2570 with myocardial infarction, and 2762 with ischaemic stroke. We also studied 13 974 individuals from the Copenhagen City Heart Study recruited in 1976-78. During up to 43 years of follow-up, 1033 were diagnosed with PAD, 2236 with myocardial infarction, and 1976 with ischaemic stroke. Remnant cholesterol was calculated from a standard lipid profile. Diagnoses were from Danish nationwide health registries. In the Copenhagen General Population Study, elevated remnant cholesterol levels were associated with higher risk of PAD, up to a multivariable adjusted hazard ratio (HR) of 4.8 (95% confidence interval 3.1-7.5) for individuals with levels ≥1.5 mmol/L (58 mg/dL) vs. <0.5 mmol/L (19 mg/dL). Corresponding results were 4.2 (2.9-6.1) for myocardial infarction and 1.8 (1.4-2.5) for ischaemic stroke. In the Copenhagen City Heart Study, corresponding HRs were 4.9 (2.9-8.5) for PAD, 2.6 (1.8-3.8) for myocardial infarction, and 2.1 (1.5-3.1) for ischaemic stroke. CONCLUSION: Elevated remnant cholesterol is associated with a five-fold increased risk of PAD in the general population, higher than for myocardial infarction and ischaemic stroke.

Severe α1-antitrypsin deficiency associated with lower blood pressure and reduced risk of ischemic heart disease: a cohort study of 91,540 individuals and a meta-analysis.

BACKGROUND: Increased elastase activity in α1-antitrypsin deficiency may affect elasticity of the arterial walls, and thereby blood pressure and susceptibility to cardiovascular disease. We hypothesized that severe α1-antitrypsin deficiency is associated with reduced blood pressure and susceptibility to cardiovascular disease. METHODS: We genotyped 91,353 adults randomly selected from the Danish general population and 187 patients from the Danish α1-Antitrypsin Deficiency Registry and recorded baseline blood pressure, baseline plasma lipids and cardiovascular events during follow-up. 185 participants carried the ZZ genotype, 207 carried the SZ genotype and 91,148 carried the MM genotype. RESULTS: α1-Antitrypsin deficiency was associated with decreases in blood pressure of up to 5 mmHg for systolic blood pressure and up to 2 mmHg for diastolic blood pressure, in ZZ vs SZ vs MM individuals (trend test, P's ≤ 0.01). Plasma triglycerides and remnant cholesterol were reduced in ZZ individuals compared with MM individuals (t-test, P's < 0.001). α1-Antitrypsin deficiency was associated with lower risk of myocardial infarction (trend test P = 0.03), but not with ischemic heart disease, ischemic cerebrovascular disease or hypertension (trend test, P's ≥ 0.59). However, when results for ischemic heart disease were summarized in meta-analysis with results from four previous studies, individuals with versus without α1-antitrypsin deficiency had an odds ratio for ischemic heart disease of 0.66 (95% CI:0.53-0.84). CONCLUSIONS: Individuals with severe α1-antitrypsin deficiency have lower systolic and diastolic blood pressure, lower plasma triglycerides and remnant cholesterol, reduced risk of myocardial infarction, and a 34% reduced risk of ischemic heart disease.

Risk of ulcerative colitis and Crohn's disease in smokers lacks causal evidence.

Smoking has been associated with opposing risks of ulcerative colitis and Crohn's disease. Whether these observational associations reflect actual causal associations, confounding, or reverse causation is unclear. Using a Mendelian randomization approach, we tested the hypothesis that smoking protects against ulcerative colitis and is a cause of Crohn's disease. We included 118,683 white Danes aged ≥ 20 from the Copenhagen General Population Study (2003-2015) and the Copenhagen City Heart Study (1991-94 and 2001-03). During follow-up until 2018, we investigated the association of smoking and CHRNA3 rs1051730, where the T-allele is strongly associated with nicotine dependence, with risk of ulcerative colitis and Crohn's disease. We identified 1312 cases of ulcerative colitis and 671 cases of Crohn's disease. Compared to never-smokers, multivariable adjusted hazard ratios (HRs) for ulcerative colitis were 1.69(95% confidence interval [CI] 1.32-2.15) in former smokers and 2.27(1.74-2.96) in current smokers. Corresponding HRs for Crohn's disease were 1.31(0.93-1.84) and 1.93(1.34-2.78), respectively. Among ever-smokers when compared to non-carriers of the CHRNA3 rs1051730 T-allele, age and sex adjusted HRs for risk of ulcerative colitis were 1.03(95%CI 0.89-1.18) in heterozygotes and 0.91(0.72-1.16) in homozygotes. Corresponding HRs for Crohn's disease were 1.05(0.87-1.28) and 1.02(0.74-1.41), respectively. In a meta-analysis combined with UK Biobank, there was no evidence that CHRNA3 rs1051730 was associated with risk of ulcerative colitis or Crohn's disease. In conclusion, current versus never-smoking was associated with unexpected 2.3-fold risk of ulcerative colitis and expected 1.9-fold risk of Crohn's disease in prospective analyses; however, genetic evidence of lifelong increased smoking intensity did not support causal relationships.

The physical activity paradox in cardiovascular disease and all-cause mortality: the contemporary Copenhagen General Population Study with 104 046 adults.

AIMS: Leisure time physical activity associates with reduced risk of cardiovascular disease and all-cause mortality, while these relationships for occupational physical activity are unclear. We tested the hypothesis that leisure time physical activity associates with reduced major adverse cardiovascular events (MACE) and all-cause mortality risk, while occupational physical activity associates with increased risks. METHODS AND RESULTS: We studied 104 046 women and men aged 20-100 years in the Copenhagen General Population Study with baseline measurements in 2003-2014 and median 10-year follow-up. Both leisure and occupational physical activity were based on self-report with four response categories. We observed 7913 (7.6%) MACE and 9846 (9.5%) deaths from all causes. Compared to low leisure time physical activity, multivariable adjusted (for lifestyle, health, living conditions, and socioeconomic factors) hazard ratios for MACE were 0.86 (0.78-0.96) for moderate, 0.77 (0.69-0.86) for high, and 0.85 (0.73-0.98) for very high activity; corresponding values for higher occupational physical activity were 1.04 (0.95-1.14), 1.15 (1.04-1.28), and 1.35 (1.14-1.59), respectively. For all-cause mortality, corresponding hazard ratios for higher leisure time physical activity were 0.74 (0.68-0.81), 0.59 (0.54-0.64), and 0.60 (0.52-0.69), and for higher occupational physical activity 1.06 (0.96-1.16), 1.13 (1.01-1.27), and 1.27 (1.05-1.54), respectively. Similar results were found within strata on lifestyle, health, living conditions, and socioeconomic factors, and when excluding individuals dying within the first 5 years of follow-up. Levels of the two domains of physical activity did not interact on risk of MACE (P = 0.40) or all-cause mortality (P = 0.31). CONCLUSION: Higher leisure time physical activity associates with reduced MACE and all-cause mortality risk, while higher occupational physical activity associates with increased risks, independent of each other.

HIV infection is associated with thoracic and abdominal aortic aneurysms: a prospective matched cohort study.

AIMS: Little is known about the prevalence of aortic aneurysms among people living with HIV (PLWH). We investigated whether HIV status is independently associated with having aortic aneurysms. Furthermore, we determined risk factors associated with aortic aneurysms in PLWH. METHODS AND RESULTS: PLWH aged ≥40 years (n = 594) were recruited from the Copenhagen Comorbidity in HIV Infection study and matched for age and sex with uninfected controls (n = 1188) from the Copenhagen General Population Study. Aortic dimensions were assessed using contrast enhanced computed tomography. Aortic aneurysms were defined according to the European Society of Cardiology guidelines, i.e. an aortic dilation of ≥50% or an infrarenal aortic diameter of ≥30 mm. Among PLWH and uninfected controls, the median (interquartile range) age was 52 (47-60) and 52 (48-61) and 88% and 90% were male, respectively. We found 46 aneurysms in 42 (7.1%) PLWH and 31 aneurysms in 29 (2.4%) uninfected controls (P < 0.001). PLWH had a significantly higher prevalence of ascending aortic aneurysms and infrarenal aortic aneurysms. In an adjusted model, HIV was independently associated with aortic aneurysms (adjusted odds ratio; 4.51 [95% confidence interval 2.56-8.08], P < 0.001). Within PLWH, obesity and hepatitis B co-infection were associated with aortic aneurysms. CONCLUSION: PLWH had four-fold higher odds of aortic aneurysms compared to uninfected controls, and HIV status was independently associated with aortic aneurysms. Among PLWH, age, obesity and hepatitis B co-infection were associated with higher odds of aortic aneurysms. Our findings suggest that increased attention to aortic aneurysms in PLWH may be beneficial.

Elevated LDL cholesterol and increased risk of myocardial infarction and atherosclerotic cardiovascular disease in individuals aged 70-100 years: a contemporary primary prevention cohort.

BACKGROUND: Findings of historical studies suggest that elevated LDL cholesterol is not associated with increased risk of myocardial infarction and atherosclerotic cardiovascular disease in patients older than 70 years. We aimed to test this hypothesis in a contemporary population of individuals aged 70-100 years. METHODS: We included in our analysis individuals (aged 20-100 years) from the Copenhagen General Population Study (CGPS) who did not have atherosclerotic cardiovascular disease or diabetes at baseline and who were not taking statins. Standard hospital assays were used to measure LDL cholesterol. We calculated hazard ratios (HRs) and absolute event rates for myocardial infarction and atherosclerotic cardiovascular disease, and we estimated the number needed to treat (NNT) in 5 years to prevent one event. FINDINGS: Between Nov 25, 2003, and Feb 17, 2015, 91 131 individuals were enrolled in CGPS. During mean 7·7 (SD 3·2) years of follow-up (to Dec 7, 2018), 1515 individuals had a first myocardial infarction and 3389 had atherosclerotic cardiovascular disease. Risk of myocardial infarction per 1·0 mmol/L increase in LDL cholesterol was augmented for the overall population (HR 1·34, 95% CI 1·27-1·41) and was amplified for all age groups, particularly those aged 70-100 years. Risk of atherosclerotic cardiovascular disease was also raised per 1·0 mmol/L increase in LDL cholesterol overall (HR 1·16, 95% CI 1·12-1·21) and in all age groups, particularly those aged 70-100 years. Risk of myocardial infarction was also increased with a 5·0 mmol/L or higher LDL cholesterol (ie, possible familial hypercholesterolaemia) versus less than 3·0 mmol/L in individuals aged 80-100 years (HR 2·99, 95% CI 1·71-5·23) and in those aged 70-79 years (1·82, 1·20-2·77). Myocardial infarction and atherosclerotic cardiovascular disease events per 1000 person-years for every 1·0 mmol/L increase in LDL cholesterol were highest in individuals aged 70-100 years, with number of events lower with younger age. The NNT in 5 years to prevent one myocardial infarction or atherosclerotic cardiovascular disease event if all people were given a moderate-intensity statin was lowest for individuals aged 70-100 years, with the NNT increasing with younger age. INTERPRETATION: In a contemporary primary prevention cohort, people aged 70-100 years with elevated LDL cholesterol had the highest absolute risk of myocardial infarction and atherosclerotic cardiovascular disease and the lowest estimated NNT in 5 years to prevent one event. Our data are important for preventive strategies aimed at reducing the burden of myocardial infarction and atherosclerotic cardiovascular disease in the growing population aged 70-100 years. FUNDING: None.

High Risk of Fatty Liver Disease Amplifies the Alanine Transaminase-Lowering Effect of a HSD17B13 Variant.

A common loss-of-function variant in HSD17B13 (rs72613567:TA) was recently found to protect from chronic liver disease. Whether the variant confers protection from specific risk factors for liver disease is unclear. We tested the association of rs72613567 with plasma levels of alanine transaminase (ALT) and clinical liver disease and mortality in 111,612 individuals from the Danish general population, including 497 with cirrhosis and 113 with hepatocellular carcinoma. HSD17B13 rs72613567:TA was associated with stepwise lower levels of plasma ALT of up to 1.3 U/L in TA/TA homozygotes versus T/T homozygotes. For each TA-allele, the risk of cirrhosis and hepatocellular carcinoma was reduced by 15% and 28%, respectively. In prospective analyses, the TA-allele was associated with up to 33% lower rates of liver-related mortality in the general population, and with up to 49% reduced liver-related mortality in patients with cirrhosis. The ALT-lowering effect of rs72613567:TA was amplified by increasing adiposity, alcohol consumption, and genetic risk of fatty liver disease. The TA-allele was associated with only marginally lower ALT in lean nondrinkers with low genetic risk of hepatic steatosis. In contrast, compared with T/T homozygotes, TA/TA homozygotes had 12% to 18% lower plasma ALT among the most obese, in heavy drinkers, and in individuals carrying three or four steatogenic alleles in patatin-like phospholipase domain-containing protein 3 (PNPLA3) and transmembrane 6 superfamily 2 (TM6SF2). Conclusion: High risk of fatty liver disease amplifies the ALT-lowering effect of HSD17B13 rs72613567:TA in the Danish general population.

The Danish comorbidity in liver transplant recipients study (DACOLT): a non-interventional prospective observational cohort study.

BACKGROUND: Liver transplantation is the only curative treatment for patients with end-stage liver disease. Short-term survival has improved due to improved surgical techniques and greater efficacy of immunosuppressive drugs. However, long-term survival has not improved to the same extent as the short-term survival, and the 10-year survival after liver transplantation is 60%. In addition to liver- and transplant-related causes, comorbidities such as cardiovascular, pulmonary, renal, and metabolic diseases have emerged as leading causes of morbidity and mortality in liver transplant recipients. The objective of this study is to assess the burden of comorbidities and identify both liver- and transplant-related risk factors as well as traditional risk factors that contribute to the pathogenesis of comorbidity in liver transplant recipients. METHODS/DESIGN: The Danish Comorbidity in Liver Transplant Recipients (DACOLT) study is an observational, longitudinal study. We aim to include all adult liver transplant recipients in Denmark (n = approx. 600). Participants will be matched by sex and age to controls from the Copenhagen General Population Study (CGPS) and the Copenhagen City Heart Study (CCHS). Physical and biological measures including blood pressure, ankle-brachial index, spirometry, exhaled nitric oxide, electrocardiogram, transthoracic echocardiography, computed tomography (CT) angiography of the heart, unenhanced CT of chest and abdomen and blood samples will be collected using uniform protocols in participants in DACOLT, CGPS, and CCHS. Blood samples will be collected and stored in a research biobank. Follow-up examinations at regular intervals up to 10 years of follow-up are planned. DISCUSSION: There is no international consensus standard for optimal clinical care or monitoring of liver transplant recipients. This study will determine prevalence, incidence and risk factors for comorbidity in liver transplant recipients and may be used to provide evidence for guidelines on management, treatment and screening and thereby contribute to improvement of the long-term survival. Trial registration ClinicalTrials.gov: NCT04777032; date of registration: March 02, 2021.

2019 vs. 2016 ESC/EAS statin guidelines for primary prevention of atherosclerotic cardiovascular disease.

AIMS: The 2019 vs. 2016 European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) dyslipidaemia guidelines contains new recommendations for primary prevention with statins; however, the potential impact of these changes is unclear. We compared the 2019 and 2016 guidelines regarding statin eligibility and potential impact on prevention of atherosclerotic cardiovascular disease (ASCVD) in the general population. METHODS AND RESULTS: We examined 45 750 individuals aged 40-75 from the Copenhagen General Population Study, all free of ASCVD and statin use at baseline. During the 9.2-year follow-up, 3337 experienced ASCVD (myocardial infarction, stroke, and cardiovascular death). For Class I/A recommendations, 32.3% (95% confidence interval: 31.8-32.7) and 15.4% (15.1-15.7) of individuals were statin eligible according to the 2019 and 2016 guidelines. The increased statin eligibility by the 2019 guidelines was explained by lower low-density lipoprotein cholesterol (LDL-C) thresholds alone (explaining 33.2%), older age range alone (49.4%), older age range in combination with lower LDL-C thresholds (14.7%), and updated SCORE risk algorithm (2.8%). If fully implemented, the estimated percentage of ASCVD events that can be prevented by using high-intensity statins for 10 years were 25% and 11% with the 2019 and 2016 guidelines. Mainly because of older age range in the 2019 guidelines, the corresponding estimated numbers needed to treat (NNT) to prevent one ASCVD event were 19 and 20. CONCLUSION: Due to lower LDL-C threshold and older age range, the 2019 vs. 2016 ESC/EAS guidelines doubles the number of individuals eligible for primary prevention with statins. This considerably improves the potential for ASCVD prevention in the general population, with similar NNT to prevent one event.

Causal Relationship between Plasma Adiponectin and Body Mass Index: One- and Two-Sample Bidirectional Mendelian Randomization Analyses in 460 397 Individuals.

BACKGROUND: Adiponectin is a protein hormone produced by adipocytes that may play an important role in obesity. However, the causal interrelation between plasma adiponectin and body mass index (BMI) is still uncertain. We tested the hypotheses that (a) plasma adiponectin and BMI are inversely associated observationally, (b) genetically high BMI is associated with lower plasma adiponectin, and (c) genetically high plasma adiponectin is associated with lower BMI. METHODS: Information on 108 896 individuals from the Copenhagen General Population Study was used in observational and bidirectional one-sample Mendelian randomization analyses, using 5 genetic variants for BMI and 3 for adiponectin. For independent confirmation, information on 322 154 individuals from the GIANT consortium, and 29 347 individuals from the ADIPOGen consortium was used in bidirectional two-sample Mendelian randomization analysis, using 68 genetic variants for BMI and 14 for adiponectin. RESULTS: In observational analyses, a 1 kg/m2 increase in BMI was associated with -0.44 µg/mL (95% confidence interval: -0.46, -0.42) in plasma adiponectin, whereas a 1 µg/mL increase in plasma adiponectin was associated with -0.11 kg/m2 (-0.12, -0.11) in BMI. In causal genetic analyses, no associations were observed between BMI and plasma adiponectin and vice versa. In one-sample Mendelian randomization analyses, a 1 kg/m2 genetically determined increase in BMI was associated with -0.13 µg/mL (-0.53, 0.28) in plasma adiponectin, whereas a 1 µg/mL genetically determined increase in plasma adiponectin was associated with 0.01 kg/m2 (-0.05, 0.07) in BMI. Corresponding estimates in the two-sample Mendelian randomization analyses were 0.03 µg/mL (-0.02, 0.07) and 0.03 kg/m2(-0.02, 0.07), respectively. CONCLUSIONS: Observationally, plasma adiponectin and BMI are inversely associated. In contrast, genetically high plasma adiponectin is unlikely to influence BMI, and genetically high BMI is unlikely to influence plasma adiponectin.

Smoking and Increased White and Red Blood Cells.

Objective- Whether tobacco smoking causally affects white and red blood cells and thrombocyte counts is unknown. Using a Mendelian randomization approach, we tested the hypothesis that smoking causes increases in these blood cell indices. Approach and Results- We included 104 607 white Danes aged 20 to 100 years from the Copenhagen General Population Study with information on blood cell indices, smoking habits, and CHRNA3 (alpha 3 nicotinic cholinergic receptor) rs1051730 genotype, where the T allele causes higher tobacco consumption; 41 759 were former smokers and 17 852 current smokers. In multivariable adjusted observational analyses and compared with never smokers, white blood cells were associated with up to 19% increases, thrombocytes with up to 4.7% increases, and red blood cell indices with up to 2.3% increases in former and current smokers. All associations were dose dependent, with tobacco consumption but for white blood cells and thrombocytes also dependent on smoking cessation time in former smokers; highest increases were for <1-year smoking cessation and lowest increases for >10-year smoking cessation. In age- and sex-adjusted genetic analyses, percent differences per T allele increase in current smokers were 1.15% (95% CI, 0.61%-1.68%) for leukocytes, 1.07% (0.38%-1.76%) for neutrophils, 1.34% (0.66%-2.02%) for lymphocytes, 1.50% (0.83%-2.18%) for monocytes, -0.60% (-1.91% to 0.74%) for eosinophils, 0.17% (-0.94% to 1.29%) for basophils, 0.38% (-0.17% to 0.93%) for thrombocytes, 0.04% (-0.14% to 0.23%) for erythrocytes, 0.34% (0.17% to 0.50%) for hematocrit, 0.26% (0.09% to 0.43%) for hemoglobin, and 0.29% (0.18% to 0.41%) for mean corpuscular volume. Conclusions- Smoking causes increased blood leukocytes, neutrophils, lymphocytes, and monocytes, as well as increased hematocrit, hemoglobin, and mean corpuscular volume. The observational smoking relationships were long term for white blood cells and short term for red blood cell indices.

Incidental lymphopenia and mortality: a prospective cohort study.

BACKGROUND: It is unknown if incidental lymphopenia detected in the general population is associated with higher all-cause and cause-specific mortality. We aimed to identify the associations between lymphopenia and all-cause and cause specific mortality. METHODS: In a prospective cohort study, we examined and followed participants enrolled in the Copenhagen General Population Study between November 2003 and April 2015. In our analysis, we modelled risks using Cox proportional hazards regression for 3 groups: participants with a lymphocyte count below the 2.5th percentile; those with a lymphocyte count at or between the 2.5th and 97.5th percentiles (reference category); and those with a lymphocyte count above the 97.5th percentile. RESULTS: The cohort included 108 135 participants with a median age of 68 years. During a median follow-up of 9 (interquartile range [IQR] 0-14) years, 10 372 participants died. We found that participants with lymphopenia (lymphocyte count < 1.1 × 109/L) compared with those with a lymphocyte count in the reference range (1.1-3.7 × 109/L) had higher mortality with multivariable adjusted hazard ratios (HRs) of 1.63 (95% confidence interval [CI] 1.51-1.76) for all causes, 1.67 (95% CI 1.42-1.97) for nonhematologic cancers, 2.79 (95% CI 1.82-4.28) for hematologic cancers, 1.88 (95% CI 1.61-2.20) for cardiovascular diseases, 1.88 (95% CI 1.55-2.29) for respiratory diseases, 1.86 (95% CI 1.53-2.25) for infectious diseases, and 1.50 (95% CI 1.19-1.88) for other causes. For all-cause mortality, the highest absolute 2-year risks of death were observed in women (61%) and men (75%) who smoked and were aged 80 years or older with lymphocyte counts less than 0.5 × 109/L. Participants with a lymphocyte count higher than the reference category had increased mortality (adjusted HR 1.17, 95% CI 1.04-1.31). INTERPRETATION: We found that lymphopenia was associated with an increased risk of all-cause and cause-specific mortality.

Comparison of Five Major Guidelines for Statin Use in Primary Prevention in a Contemporary General Population.

Background: Five major organizations recently published guidelines for using statins to prevent atherosclerotic cardiovascular disease (ASCVD): in 2013, the American College of Cardiology/American Heart Association (ACC/AHA); in 2014, the United Kingdom's National Institute for Health and Care Excellence (NICE); and in 2016, the Canadian Cardiovascular Society (CCS), the U.S. Preventive Services Task Force (USPSTF), and the European Society of Cardiology/European Atherosclerosis Society (ESC/EAS). Objective: To compare the utility of these guidelines for primary prevention of ASCVD. Design: Observational study of actual ASCVD events during 10 years, followed by a modeling study to estimate the effectiveness of different guidelines. Setting: The Copenhagen General Population Study. Participants: 45 750 Danish persons aged 40 to 75 years who did not use statins and did not have ASCVD at baseline. Measurements: The number of participants eligible to use statins according to each guideline and the estimated number of ASCVD events that statins could have prevented. Results: The percentage of participants eligible for statins was 44% by the CCS guideline, 42% by ACC/AHA, 40% by NICE, 31% by USPSTF, and 15% by ESC/EAS. The estimated percentage of ASCVD events that could have been prevented by using statins for 10 years was 34% for CCS, 34% for ACC/AHA, 32% for NICE, 27% for USPSTF, and 13% for ESC/EAS. Limitation: This study was limited to primary prevention in white Europeans. Conclusion: Guidelines recommending that more persons use statins for primary prevention of ASCVD should prevent more events than guidelines recommending use by fewer persons. Primary Funding Source: Copenhagen University Hospital.

Lymphopenia and risk of infection and infection-related death in 98,344 individuals from a prospective Danish population-based study.

BACKGROUND: Neutropenia increases the risk of infection, but it is unknown if this also applies to lymphopenia. We therefore tested the hypotheses that lymphopenia is associated with increased risk of infection and infection-related death in the general population. METHODS AND FINDINGS: Of the invited 220,424 individuals, 99,191 attended examination. We analyzed 98,344 individuals from the Copenhagen General Population Study (Denmark), examined from November 25, 2003, to July 9, 2013, and with available blood lymphocyte count at date of examination. During a median of 6 years of follow-up, they developed 8,401 infections and experienced 1,045 infection-related deaths. Due to the completeness of the Danish civil and health registries, none of the 98,344 individuals were lost to follow-up, and those emigrating (n = 385) or dying (n = 5,636) had their follow-up truncated at the day of emigration or death. At date of examination, mean age was 58 years, and 44,181 (44.9%) were men. Individuals with lymphopenia (lymphocyte count < 1.1 × 109/l, n = 2,352) compared to those with lymphocytes in the reference range (1.1-3.7 × 109/l, n = 93,538) had multivariable-adjusted hazard ratios of 1.41 (95% CI 1.28-1.56) for any infection, 1.31 (1.14-1.52) for pneumonia, 1.44 (1.15-1.79) for skin infection, 1.26 (1.02-1.56) for urinary tract infection, 1.51 (1.21-1.89) for sepsis, 1.38 (1.01-1.88) for diarrheal disease, 2.15 (1.16-3.98) for endocarditis, and 2.26 (1.21-4.24) for other infections. The corresponding hazard ratio for infection-related death was 1.70 (95% CI 1.37-2.10). Analyses were adjusted for age, sex, smoking status, cumulative smoking, alcohol intake, body mass index, plasma C-reactive protein, blood neutrophil count, recent infection, Charlson comorbidity index, autoimmune diseases, medication use, and immunodeficiency/hematologic disease. The findings were robust in all stratified analyses and also when including only events later than 2 years after first examination. However, due to the observational design, the study cannot address questions of causality, and our analyses might theoretically have been affected by residual confounding and reverse causation. In principle, fluctuating lymphocyte counts over time might also have influenced analyses, but lymphocyte counts in 5,181 individuals measured 10 years after first examination showed a regression dilution ratio of 0.68. CONCLUSIONS: Lymphopenia was associated with increased risk of hospitalization with infection and increased risk of infection-related death in the general population. Notably, causality cannot be deduced from our data.

Complement C3 and Risk of Diabetic Microvascular Disease: A Cohort Study of 95202 Individuals from the General Population.

BACKGROUND: Whether the complement system is involved in the development of diabetic microvascular disease is unknown. We tested the hypothesis that high concentrations of complement C3 are associated with increased risk of diabetic retinopathy, nephropathy, and neuropathy in individuals from the general population. METHODS: We studied 95202 individuals from the general population with baseline measurements of complement C3, genotyped for rs1065489, rs429608, and rs448260 determining concentrations of complement C3, and enrolled in the Copenhagen General Population Study from 2003 through 2013, following them until April 10, 2013. Rs1065489, rs429608, and rs448260 were identified with genome-wide association scans in 3752 individuals from the Copenhagen City Heart Study. RESULTS: The cumulative incidence was increased from the lowest tertile to the highest tertile of complement C3 for diabetic retinopathy (log-rank trend, P = 1 × 10-20), nephropathy (P = 7 × 10-15), and neuropathy (P = 5 × 10-10). Multifactorially adjusted hazard ratios for a 1 SD higher concentration of complement C3 were 1.87 (95% CI, 1.61-2.18) for diabetic retinopathy, 1.90 (1.62-2.23) for diabetic nephropathy, and 1.56 (1.29-1.89) for diabetic neuropathy. The multifactorially adjusted hazard ratio for individuals with the highest vs lowest tertile of complement C3 was 3.29 (1.78-6.07) for retinopathy, 2.71 (1.42-5.16) for nephropathy, and 2.40 (1.26-4.54) for neuropathy. CONCLUSIONS: High baseline concentrations of complement C3 were associated with increased risk of diabetic retinopathy, nephropathy, and neuropathy in individuals from the general population. These epidemiological findings were substantiated by a Mendelian randomization approach, potentially indicating causality.