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Background Elevated apolipoprotein B (apoB) and elevated apoB/apoA-1 ratio increase the risk of myocardial infarction (MI) and stroke, whereas high apoA-1 is protective. We study how these apolipoproteins are associated with major adverse cardiovascular events (MACEs), whether apoA-1 contributes to this association, and whether abnormal values occur decades before such events develop. Methods and findings In the Swedish AMORIS (Apolipoprotein-related MOrtality RISk) cohort study, 137,100 men and women aged 25-84 years were followed an average 17.8 years. ApoB, apoA-1, and the apoB/apoA-1 ratio were analysed in relation to MACEs (non-fatal MI, stroke, and cardiovascular [CV] mortality), yielding 22,473 events. Hazard ratios (HRs) were estimated using Cox regression. Kaplan-Meier estimates were used to investigate the relationship of MACEs with increasing quintiles of the apoB/apoA-1 ratio in all age groups for both sexes. In nested case-control analyses, cases were randomly matched to age- and sex-matched controls, yielding population trajectories for apolipoproteins. Increased level of apoB and increased apoB/apoA-1 ratio were associated with risk of MACE and all clinical sub-components in both men and women across all ages (10th versus first decile in both sexes combined: HR 1.7 for MACE and 2.7 for non-fatal MI). Decreased values of apoA-1 potentiated the impact of apoB at all levels of apoB (on average across apoB range: 40% increase in HR for MACE and 72% increase in HR for non-fatal MI), indicating that the apoB/apoA-1 ratio covers a broader range of persons with dyslipidaemia at risk than apoB alone. In both men and women, MACEs occurred earlier on average for each increasing quintile of the apoB/apoA-1 ratio. Individuals with the highest levels of apoB/apoA-1 ratio experienced CV events on average several years earlier than those with lower ratios. Higher apoB/apoA-1 ratio in cases of MACE versus controls was seen already about 20 years before the event. A li

Previous literature indicates that pre-diagnostic diabetes and blood glucose levels are inversely related to glioma risk. To replicate these findings and determine whether they could be attributed to excess glucose consumption by the preclinical tumour, we used data from the Apolipoprotein MOrtality RISk (AMORIS) (n = 528,580) and the Metabolic syndrome and Cancer project (Me-Can) cohorts (n = 269,365). We identified individuals who were followed for a maximum of 15 years after their first blood glucose test until glioma diagnosis, death, emigration or the end of follow-up. Hazard ratios (HRs), 95% confidence intervals (CIs) and their interactions with time were estimated using Cox time-dependent regression. As expected, pre-diagnostic blood glucose levels were inversely related to glioma risk (AMORIS, P-trend = 0.002; Me-Can, P-trend = 0.04) and pre-diagnostic diabetes (AMORIS, HR = 0.30, 95% CI 0.17 to 0.53). During the year before diagnosis, blood glucose was inversely associated with glioma in the AMORIS (HR = 0.78, 95% CI 0.66 to 0.93) but not the Me-Can cohort (HR = 0.99, 95% CI 0.63 to 1.56). This AMORIS result is consistent with our hypothesis that excess glucose consumption by the preclinical tumour accounts for the inverse association between blood glucose and glioma. We discuss additional hypothetical mechanisms that may explain our paradoxical findings.

Lifestyle-related risk factors such as hyperglycemia and dyslipidemia have been associated with several cancers. However, studies exploring their link with prostate cancer (PCa) clinicopathological characteristics are sparse and inconclusive. Here, we investigated the associations between serum metabolic markers and PCa clinicopathological characteristics. The study comprised 14,294 men from the Swedish Apolipoprotein MOrtality RISk (AMORIS) cohort who were diagnosed with PCa between 1996 and 2011. Univariate and multivariable logistic regression were used to investigate the relation between glucose, triglycerides and total cholesterol and PCa risk categories, PSA, Gleason score, and T-stage. Mean age at time of PCa diagnosis was 69 years. Men with glucose levels >6.9 mmol/L tend to have PSA<4 mu g/L, while those with glucose levels of 5.6-6.9 mmol/L had a greater odds of PSA>20 mu g/L compared to PSA 4.0-9.9 mu g/L. Hypertriglyceridemia was also positively associated with PSA>20 mu g/L. Hyperglycemic men had a greater odds of intermediate-and high-grade PCa and advanced stage or metastatic PCa. Similarly, hypertriglyceridemia was positively associated with high-grade PCa. There was also a trend toward an increased odds of intermediate risk localized PCa and advanced stage PCa among men with hypertriglyceridemia. Total cholesterol did not have any statistically significant association with any of the outcomes studied. Our findings suggest that high serum levels of glucose and triglycerides may influence PCa aggressiveness and severity. Further investigation on the role of markers of glucose and lipid metabolism in influencing PCa aggressiveness and severity is needed as this may help define important targets for intervention.

Prior findings linking allergy and cancer have been inconsistent, which may be driven by diverse assessment methods. We used serum specific immunoglobulin E (IgE) against common inhalant allergens that was assessed prior to cancer diagnosis in studying this association. We selected 8,727 Swedish men and women who had measurements of serum allergen-specific IgE and total IgE between 1992 and 1996. Multivariable Cox regression using age as a timescale was performed to assess the associations of IgE sensitization, defined by any levels of serum specific IgE >= 35 kU/L, with risk of overall and specific cancers. A test for trend was performed by assigning scores derived from allergen-specific IgE levels at baseline as an ordinal scale. Kaplan-Meier curves and log-rank test were used to assess cancer survival by IgE sensitization status. During a mean follow-up of 16 year, 689 persons were diagnosed with cancer. We found an inverse association between IgE sensitization and cancer risk, with a hazard ratio (HR) of 0.83 and 95% confidence intervals (CI) of 0.70-0.99. A similar trend was seen with specific IgE scores overall (P-trend = 0.007) and in women (P-trend = 0.01). Although IgE sensitization was not associated with risk of common site-specific cancers, serum specific IgE scores were inversely associated with melanoma risk in men and women combined, and with risk of female breast and gynecological cancers combined. No association with survival was observed. The association between circulating IgE levels and incident cancer may point toward a role of T-helper 2 (T(H)2)-biased response in development of some cancers.

Background In recent clinical guidelines, individuals with chronic kidney disease are considered to have a similar 10-year absolute risk of cardiovascular death as individuals with diabetes or established cardiovascular disease. There is limited evidence to support this claim. Methods We investigated the 10-year risk for cardiovascular death in individuals with moderate or severe chronic kidney disease (glomerular filtration rate of 30-60 or <30mL/min/1.73m(2), respectively) in a cohort of primary care health check-ups in Stockholm, Sweden (n=295,191, 46% women, 4290 cardiovascular deaths during 10 years follow-up). We also assessed the risk associated with diabetes or cardiovascular disease. The inclusion criteria, exposure, study outcome and follow-up period adhered strictly to the definitions of the European Society of Cardiology guidelines. Results The absolute 10-year risk of cardiovascular death was 3.9% and 14.0% in individuals with moderate and severe chronic kidney disease, respectively, but was substantially lower in women and in younger individuals. The risk in individuals with prevalent diabetes and cardiovascular disease was approximately two and three times higher compared to the risk estimate for moderate chronic kidney disease (hazard ratio (HR) 4.1, 95% confidence interval (CI) 3.8-4.5 and HR 6.2, 95% CI 5.7-6.7 vs. HR 2.3 95% CI 2.0-2.6, respectively) while the risk for individuals with severe chronic kidney disease appeared more congruent to that of diabetes and cardiovascular disease (HR 5.5, 95% CI 3.3-8.9). Conclusions Although moderate chronic kidney disease is an independent predictor for an increased 10-year risk of cardiovascular death, only those with severe chronic kidney disease had similar risk to those with diabetes or cardiovascular disease.

Background: There is evidence that high level of serum lactate dehydrogenase (LDH) is associated with poorer overall survival in several malignancies, but its link to cancer-specific survival is unclear. Methods: A total of 7895 individuals diagnosed with cancer between 1986 and 1999 were selected for this study. Multivariable Cox proportional hazards regression was used to assess overall and cancer-specific death by the z-score and clinical categories of serum LDH prospectively collected within 3 years before diagnosis. Site-specific analysis was performed for major cancers. Analysis was repeated by different lag times between LDH measurements and diagnosis. Results: At the end of follow-up, 5799 participants were deceased. Hazard ratios (HRs) and 95% confidence intervals (CIs) for overall and cancer-specific death in the multivariable model were 1.43 (1.31-1.56) and 1.46 (1.32-1.61), respectively, for high compared with low prediagnostic LDH. Site-specific analysis showed high LDH to correlate with an increased risk of death from prostate, pulmonary, colorectal, gastro-oesophageal, gynaecological and haematological cancers. Serum LDH assessed within intervals closer to diagnosis was more strongly associated with overall and cancer-specific death. Conclusions: Our findings demonstrated an inverse association of baseline serum LDH with cancer-specific survival, corroborating its role in cancer progression.

Background: Abnormal glucose and lipids levels may impact survival after breast cancer (BC) diagnosis, but their association to other causes of mortality such as cardiovascular (CV) disease may result in a competing risk problem. Methods: We assessed serum glucose, triglycerides (TG) and total cholesterol (TC) measured prospectively 3 months to 3 years before diagnosis in 1798 Swedish women diagnosed with any type of BC between 1985 and 1999. In addition to using Cox regression, we employed latent class proportional hazards models to capture any heterogeneity of associations between these markers and BC death. The latter method was extended to include the primary outcome (BC death) and competing outcomes (CV death and death from other causes), allowing latent class-specific hazard estimation for cause-specific deaths. Results: A lack of association between prediagnostic glucose, TG or TC with BC death was observed with Cox regression. With latent class proportional hazards model, two latent classes (Class I and II) were suggested. Class I, comprising the majority (81.5 %) of BC patients, had an increased risk of BC death following higher TG levels (HR: 1.87, 95 % CI: 1.01-3.45 for every log TG increase). Lower overall survival was observed in Class II, but no association for BC death was found. On the other hand, TC positively corresponded to CV death in Class II, and similarly, glucose to death from other causes. Conclusion: Addressing cohort heterogeneity in relation to BC survival is important in understanding the relationship between metabolic markers and cause-specific death in presence of competing outcomes.

Background: Both dietary and serum levels of inorganic phosphate (Pi) have been linked to development of cancer in experimental studies. This is the first population-based study investigating the relation between serum Pi and risk of cancer in humans. Methods: From the Swedish Apolipoprotein Mortality Risk (AMORIS) study, we selected all participants (>20 years old) with baseline measurements of serum Pi, calcium, alkaline phosphatase, glucose, and creatinine (n = 397,292). Multivariable Cox proportional hazards regression analyses were used to assess serum Pi in relation to overall cancer risk. Similar analyses were performed for specific cancer sites. Results: We found a higher overall cancer risk with increasing Pi levels in men (HR: 1.02 (95% CI: 1.00-1.04) for every SD increase in Pi), and a negative association in women (HR: 0.97 (95% CI: 0.96-0.99) for every SD increase in Pi). Further analyses for specific cancer sites showed a positive link between Pi quartiles and the risk of cancer of the pancreas, lung, thyroid gland and bone in men, and cancer of the oesophagus, lung, and nonmelanoma skin cancer in women. Conversely, the risks for developing breast and endometrial cancer as well as other endocrine cancer in both men and women were lower in those with higher Pi levels. Conclusions: Abnormal Pi levels are related to development of cancer. Furthermore, the inverse association between Pi levels and risk of breast, endometrial and other endocrine cancers may indicate the role of hormonal factors in the relation between Pi metabolism and cancer.

Objective: The aim was to investigate country or region of birth-specific prevalence and gender differences of diabetes in residents in Sweden, using Swedish-born men and women as referent. Methods: The Apolipoprotein MOrtality RISk (AMORIS) cohort was used (184,000 men and 151,453 women) aged between 20 and 80 years, with data from the CALAB laboratory, Stockholm, 1985-1996. Diabetes was defined as fasting glucose >= 7.0 mmol/L or a hospital diagnosis of diabetes. Country of birth was obtained by linkage to Swedish Censuses 1970-1990. Standardized prevalence rate ratios (SPRR) with 95% confidence intervals (95% CI) were estimated. Results: Five groups of women and one group of men had a significantly higher prevalence than Swedish-born (based on SPRR): women born in Iraq (6.0 (95% CI 1.3-28.9)), North Africa (6.9 (95% CI 3.1-15.3)), South Asia (3.1 (95% CI 1.0-10.0)), Syria (5.3 (95% CI 1.8-16.0)), Turkey (3.7 (95% CI 1.2-10.9)) and men born in other Middle Eastern countries (2.3 (95% CI 1.0-5.5)). Swedish-born men had a higher age-standardized prevalence of diabetes (3.9%) than Swedish born women ( 2.5%). A higher prevalence among men was also seen in other Western countries. In contrast, a higher age-standardized prevalence among women was observed in immigrants from Turkey (8.9% vs. 3.1%, p < 0.001), Syria (13.1% vs. 4.0%, p = 0.002), and North Africa (16.8% vs. 6.6%, p < 0.001). Conclusion: Female immigrants to Sweden from Iraq, North Africa, South Asia, Syria, and Turkey have an increased prevalence of diabetes of substantial public health concern.

Pre-clinical studies have shown that iron can be carcinogenic, but few population-based studies investigated the association between markers of the iron metabolism and risk of cancer while taking into account inflammation. We assessed the link between serum iron (SI), total-iron binding capacity (TIBC), and risk of cancer by levels of C-reactive protein (CRP) in a large population-based study (n = 220,642). From the Swedish Apolipoprotein Mortality Risk (AMORIS) study, we selected all participants (> 20 years old) with baseline measurements of serum SI, TIBC, and CRP. Multivariate Cox proportional hazards regression was carried out for standardized and quartile values of SI and TIBC. Similar analyses were performed for specific cancers (pancreatic, colon, liver, respiratory, kidney, prostate, stomach, and breast cancer). To avoid reverse causation, we excluded those with follow-up < 3 years. We found a positive association between standardized TIBC and overall cancer [HR 1.03 (95 % CI 1.01-1.05)]. No statistically significant association was found between SI and cancer risk except for postmenopausal breast cancer [HR for standardized SI 1.09 (95 % CI 1.02-1.15)]. The association between TIBC and specific cancer was only statistically significant for colon cancer [i.e., HR for standardized TIBC: 1.17 (95 % CI 1.08-1.28)]. A borderline interaction between SI and levels of CRP was observed only in stomach cancer. As opposed to pre-clinical findings for serum iron and cancer, this population-based epidemiological study showed an inverse relation between iron metabolism and cancer risk. Minimal role of inflammatory markers observed warrants further study focusing on developments of specific cancers.

Background: Observational studies have indicated that high calcium intake may prevent colorectal cancer, but as for randomized trials the results are inconclusive. Meanwhile, limited data on the link between serum calcium and cancer risk is available. We investigated the relation between serum calcium and risk of different gastrointestinal cancers in a prospective study. Methods: A cohort based on 492,044 subjects with baseline information on calcium (mmol/L) and albumin (g/L) was selected from the Swedish Apolipoprotein MOrtality RISk (AMORIS) study. Multivariable Cox proportional hazard models were used to analyse associations between standardised levels, quartiles and age/sex-specific categories of serum calcium and risk of oesophageal, stomach, colon, rectal cancer and also colorectal cancer combined, while taking into account serum albumin and other comorbidities. Results: During 12 years of follow-up, we identified 323 incident oesophageal cancers, 782 stomach cancers, 2519 colon cancers, and 1495 rectal cancers. A positive association was found between albumin-adjusted serum calcium and risk of oesophageal [HR: 4.82 (95% CI: 2.07 - 11.19) for high compared to normal age-specific calcium levels] and colon cancer [e.g. HR: 1.07 (95% CI: 1.00 - 1.14) for every SD increase of calcium] as well as colorectal cancer [e.g. HR: 1.06 (95% CI: 1.02-1.11) for every SD increase of calcium] in women. In men there were similar but weaker non-statistically significant trends. Conclusion: The positive relation between serum calcium, oesophageal cancer and colorectal cancer calls for further studies including calcium regulators to evaluate whether there is a true link between calcium metabolism and development of gastrointestinal cancer.

Background: Obesity is a risk factor for breast and ovarian cancer; the mechanisms of action are not completely understood. Perturbed lipid metabolism often accompanies obesity; we therefore ascertained the associations between lipid components and breast and ovarian cancer risk in a prospective cohort study. Methods: A total of 234,494 women with baseline measurements of triglycerides and total cholesterol and glucose were selected from the AMORIS database.A total of 27,394 had measurements of high-density lipoprotein, low-density lipoprotein, apolipoprotein (Apo) B, and A-I. Associations between quartiles and dichotomized values of lipid components and breast and ovarian cancer risk were analyzed using Cox proportional hazard models. Results: We identified 6,105 women diagnosed with breast cancer and 808 women diagnosed with ovarian cancer. A weak trend was observed between triglycerides and breast cancer (HR, 1.01, 95% Confidence Interval, 0.94-1.09; 0.93 (0.86-1.00) 0.91 (0.84-0.99), second, third, and fourth quartiles; P = 0.01). No other associations between lipid components and risk of breast cancer or ovarian cancer showed statistical significance. Conclusions: A weak protective association was found between levels of triglycerides and risk of breast cancer. Impact: An analysis including information on tumour characteristics of ovarian cancer and breast cancer may provide more insight in possible links between lipid metabolism and the risk of these cancers.