Emilie Friberg

Diabetes mellitus and risk of endometrial cancer: a meta-analysis

Aims/hypothesisDiabetes has been associated with a statistically significantly increased risk of endometrial cancer in most, but not all studies. To provide a quantitative assessment of the association between diabetes and risk of endometrial cancer, we conducted a meta-analysis of case-control studies and cohort studies.Subjects and methodsWe identified studies by a literature search of PubMed and Embase through to January 2007 and by searching the reference lists of relevant articles. Summary relative risks (RRs) with 95% CIs were calculated using random-effects model.ResultsThe analysis of diabetes (largely type 2) and endometrial cancer is based on 16 studies (three cohort and 13 case-control studies), including 96,003 participants and 7,596 cases of endometrial cancer. Twelve of the studies showed a statistically significantly increased risk and four a non-significant increased risk of endometrial cancer. In our meta-analysis we found that diabetes was statistically significantly associated with an increased risk of endometrial cancer (summary RR 2.10, 95% CI 1.75–2.53). The risk estimates were somewhat stronger among case-control (RR 2.22, 95% CI 1.80–2.74) than among cohort studies (RR 1.62, 95% CI 1.21–2.16), stronger among studies adjusting only for age (RR 2.74, 95% CI 1.87–4.00) compared with multivariate adjustment (RR 1.92, 95% CI 1.58–2.33) and slightly lower in studies performed in the USA than in those performed Europe. The analysis of type 1 diabetes and endometrial cancer was based on three studies and found a statistically significant positive association (summary RR 3.15, 95%CI 1.07–9.29).Conclusions/interpretationResults from the meta-analysis support a relationship between diabetes and increased risk of endometrial cancer.

Diabetes and Risk of Endometrial Cancer: A Population-Based Prospective Cohort Study

Although there is accumulating evidence that hyperinsulinemia in the context of insulin resistance is associated with carcinogenesis, only one prospective study of endometrial cancer incidence, in relation to diabetes, addressed this issue and showed no significant positive association. No previous study has investigated whether physical activity can modify the association between diabetes and endometrial cancer. We examined the association between diabetes and incidence of endometrial cancer and the potential effect modification by obesity and physical activity in the Swedish Mammography Cohort, a prospective cohort of 36,773 women, including 225 incident endometrial adenocarcinoma cases. After adjustments, the relative risk (RR) for endometrial cancer among women with diabetes comparing with nondiabetic women was 1.94 [95% confidence interval (95% CI), 1.23-3.08]. Among obese diabetics, the RR was 6.39 (95% CI, 3.28-12.06) compared with nonobese nondiabetic women. Among diabetics with low physical activity, the RR for endometrial cancer was 2.80 (95% CI, 1.62-4.85) compared with physically active nondiabetic women. Obese diabetics with low physical activity had a RR of 9.61 (95% CI, 4.66-19.83) compared with normal weight nondiabetic women with high physical activity. Diabetes was associated with a 2-fold increased risk, and combination of diabetes with obesity and low physical activity was associated with a further increased risk for endometrial cancer. Interventions to reduce body weight and increase physical activity may have important implications in terms of prevention of endometrial cancer and future management of diabetic subjects. (Cancer Epidemiol Biomarkers Prev 2007;16(2):268–72)

Physical Activity and Risk of Endometrial Cancer: A Population-Based Prospective Cohort Study

Physical activity is involved in the regulation of metabolic and hormonal pathways and is one of the factors important for the maintenance of body weight; obesity is a risk factor for endometrial cancer. A connection between physical activity and endometrial cancer risk through hormonal mechanisms, possibly mediated by body weight, is biologically plausible. Only one study has investigated total physical activity, and no previous study has examined leisure time inactivity directly. We investigated the association of total physical activity and different types of physical activity with risk of endometrial cancer in the Swedish Mammography Cohort, a population-based prospective cohort, including 33,723 women and 199 endometrial cancer cases. After adjustments for potential confounders (age, body mass index, parity, history of diabetes, total fruit and vegetable intake, and education), the relative risks for endometrial cancer for the second to fourth quartile of total physical activity compared with the lowest one were 0.80 [95% confidence interval (95% CI), 0.54-1.18], 0.87 (95% CI, 0.59-1.28), and 0.79 (95% CI, 0.53-1.17). High leisure time inactivity (watching TV/sitting ≥5 hours daily) compared with low was associated with increased risk of endometrial cancer (relative risk, 1.66; 95% CI, 1.05-2.61). The associations were not modified by body mass index. Findings from this study suggest that total physical activity is weakly inversely associated with endometrial cancer risk and that leisure time inactivity is statistically significantly associated with increased risk for endometrial cancer. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2136–40)

Carbohydrate intake, glycemic index and glycemic load in relation to risk of endometrial cancer: A prospective study of Swedish women

The associations of carbohydrate intake, glycemic index and glycemic load with endometrial cancer risk were examined among 61,226 participants of the Swedish Mammography Cohort who were cancer‐free at enrollment between 1987 and 1990 and completed a food frequency questionnaire. During a mean follow‐up of 15.6 years, through June 2005, 608 incident cases of endometrial adenocarcinoma were diagnosed. We observed no overall association between carbohydrate intake, glycemic index or glycemic load and incidence of endometrial cancer; the rate ratios (RRs) for the highest versus the lowest quintile were 1.12 (95% CI, 0.85–1.47) for carbohydrate intake, 1.00 (95% CI, 0.77–1.30) for glycemic index and 1.15 (95% CI, 0.88–1.51) for glycemic load. However, among obese women (body mass index, BMI ≥30 kg/m2), endometrial cancer incidence was nonsignificantly elevated in the top versus bottom quintiles of carbohydrate intake (RR, 1.68; 95% CI, 0.86–3.29) and glycemic load (RR, 1.57; 95% CI, 0.82–2.99). In a subanalysis of women who completed a follow‐up questionnaire in 1997, which collected information on physical activity, carbohydrate intake and glycemic load were positively related to endometrial cancer risk among overweight women (BMI ≥25 kg/m2) with low physical activity. In this subgroup, the multivariate RRs comparing extreme quartiles were 1.90 (95% CI, 0.84–4.31) for carbohydrate intake and 2.99 (95% CI, 1.17–7.67) for glycemic load. Results from this cohort study suggest that a high carbohydrate intake and a high glycemic load may increase the risk of endometrial cancer among overweight women with low physical activity.

Coffee drinking and risk of endometrial cancer--a population-based cohort study.

Coffee drinking has been reported to have beneficial effects on insulin resistance, which has been directly associated with endometrial cancer. Although a relationship between coffee consumption and endometrial cancer risk is biologically plausible, this hypothesis has been previously explored in only 2 prospective studies, with a small number of cases. We used data from the Swedish Mammography Cohort, a population‐based prospective cohort study of 60,634 women. During 17.6 years of follow‐up, 677 participants were diagnosed with incident endometrial cancer (adenocarcinoma). We examined the association between self‐reported coffee consumption (at baseline 1987–90 and in 1997) and endometrial cancer risk using Cox proportional hazards models. Each additional cup (200 g) of coffee per day was associated with a rate ratio (RR) of 0.90 [95% confidence interval (CI), 0.83–0.97]. In women drinking 4 or more cups of coffee a day, the RR for the risk reduction of endometrial cancer was 0.75 (95% CI, 0.58–0.97) when compared with those who drank 1 cup or less. The association seemed largely confined to overweight and obese women, who showed a respective risk reduction of 12% (95% CI, 0–23%) and 20% (95% CI, 7–31%) for every cup of coffee, but was not observed among normal‐weight women. There was a statistically significant interaction between coffee consumption and body mass index (pinteraction < 0.001). These data indicate that coffee consumption may be associated with decreased risk of endometrial cancer, especially among women with excessive body weight. If confirmed by other prospective studies, these results are of major public health significance.

Cost of Illness of Multiple Sclerosis : A Systematic Review

Background Cost-of-illness (COI) studies of Multiple Sclerosis (MS) are vital components for describing the economic burden of MS, and are frequently used in model studies of interventions of MS. We conducted a systematic review of studies estimating the COI of MS, to compare costs between studies and examine cost drivers, emphasizing generalizability and methodological choices. Material and method A literature search on studies published in English on COI of MS was performed in PubMed for the period January 1969 to January 2014, resulting in 1,326 publications. A mapping of studies using a bottom-up approach or top-down approach, respectively, was conducted for the 48 studies assessed as relevant. In a second analysis, the cost estimates were compared between the 29 studies that used a societal perspective on costs, human capital approach for indirect costs, presenting number of patients included, time-period studied, and year of price level used. Results The mapping showed that bottom-up studies and prevalence approaches were most common. The cost ratios between different severity levels within studies were relatively stable, to the ratio of 1 to 2 to 3 for disability level categories. Drugs were the main cost drivers for MS-patients with low disease severity, representing 29% to 82% of all costs in this patient group, while the main cost components for groups with more advanced MS symptoms were production losses due to MS and informal care, together representing 17% to 67% of costs in those groups. Conclusion The bottom-up method and prevalence approach dominated in studies of COI of MS. Our findings show that there are difficulties in comparing absolute costs across studies, nevertheless, the relative costs expressed as cost ratios, comparing different severity levels, showed higher resemblance. Costs of drugs were main cost drivers for less severe MS and informal care and production losses for the most severe MS.

Sickness Absence Due to Otoaudiological Diagnoses and Risk of Disability Pension: A Nationwide Swedish Prospective Cohort Study

Background Hearing difficulties are a large public health problem. Knowledge is scarce regarding risk of disability pension among people who have been sickness absent due to these difficulties. Methods A cohort including all 4,687,756 individuals living in Sweden in 2005, aged 20–64, and not on disability or old-age pension, was followed through 2009. Incidence rate ratios (RR) of disability pension with 95% confidence intervals (CI) were estimated using Cox proportional hazard models. Results In multivariable models, individuals who had a sick-leave spell due to otoaudiological diagnoses in 2005 had a 1.52-fold (95% CI: 1.43–1.62) increased risk of being granted a disability pension compared to individuals on sick leave due to other diagnoses. Hearing and tinnitus sick-leave diagnoses were associated with risk of disability pension: RR 3.38, 95% CI: 3.04–3.75, and 3.30, 95% CI: 2.95–3.68, respectively. No association was observed between sick leave due to vertigo diagnoses and disability pension whereas otological diagnoses and no sick leave were inversely associated with risk of disability pension compared to non-otoaudiological sick-leave diagnoses. Sick leave due to otoaudiological diagnoses was positively associated with risk of disability pension due to otoaudiological diagnoses and sick leave due to a tinnitus diagnosis was also associated with risk of disability pension due to mental diagnoses. The risk of disability pension among individuals with hearing or tinnitus sick-leave diagnoses was highest in the age group 35–44. Moreover, men had a slightly higher risk. Conclusion This large cohort study suggests an increased risk of disability pension among those with sickness absence due to otoaudiological diagnoses, particularly hearing and tinnitus diagnoses, compared to those with sickness absence due to non-otoaudiological diagnoses.

Long-term Alcohol Consumption and Risk of Endometrial Cancer Incidence: A Prospective Cohort Study

Alcohol consumption has been hypothesized to increase the risk of endometrial cancer. We used data from the prospective population-based Swedish Mammography Cohort including 61,226 women to examine the association between alcohol and endometrial cancer incidence. Alcohol consumption was assessed with validated food frequency questionnaires at baseline 1987 to 1990 and at follow-up in 1997. During a mean follow-up of 17.6 years, 687 endometrial cancer cases were identified in the Swedish cancer registries. We found no association between alcohol consumption and endometrial cancer risk after adjustment for age, body mass index, and smoking. The multivariable rate ratios (95% confidence intervals) for the three upper categories of long-term alcohol consumption as compared with no consumption were 1.01 (0.84-1.22) for <3.4 g/d, 1.01 (0.80-1.27) for 3.4 to 9.9 g/d, and 1.09 (0.71-1.67) for ≥10 g/d, respectively. The association did not differ by age, body mass index, folic acid intake, or postmenopausal hormone use in stratified analysis. In conclusion, our results suggest that low alcohol consumption (up to one drink per day) is unlikely to substantially influence risk of endometrial cancer. (Cancer Epidemiol Biomarkers Prev 2009;18(1):355–8)

Sucrose, High-Sugar Foods, and Risk of Endometrial Cancer—a Population-Based Cohort Study

Background: Consumption of high-sugar foods stimulates insulin production, which has been associated with endometrial cancer. Although a relationship between sucrose, high-sugar food consumption, and endometrial cancer risk is biologically plausible, this hypothesis has previously been explored in very few studies. Methods: We used data from the Swedish Mammography Cohort, including 61,226 women aged 40 to 74 years. We examined the association between consumption of total sucrose, high-sugar foods (at baseline 1987–1990 and 1997) and endometrial cancer risk by using Cox proportional hazards models to estimate incidence rate ratios (RR) with 95% CI. Results: During 18.4 years of follow-up, 729 participants were diagnosed with incident endometrial cancer. Total sucrose intake and consumption of sweet buns and cookies was associated with increased risk of endometrial cancer. RRs (with 95% CIs) for consuming more than 35 grams of sucrose per day and consuming sweet buns and cookies more than 3 times per week were 1.36 (1.04–1.77) and 1.42 (1.15–1.75) as compared with less than 15 grams of sucrose per day and consuming sweet buns and cookies less than 0.5 times per week, respectively. RRs for consuming more than 15 grams of sucrose per day as compared with 15 grams or less were 1.97 (1.27–3.04) among obese women and 1.56 (1.20–2.04) among women with low fat intake. Conclusions: These data indicate that sucrose intake and consumption of sweet buns and cookies may be associated with increased risk of endometrial cancer. Impact: Given the high intake of sweetened foods, these results have public health implications in terms of prevention of endometrial cancer. Cancer Epidemiol Biomarkers Prev; 20(9); 1831–7. ©2011 AACR.

Sources and level of income among individuals with multiple sclerosis compared to the general population: A nationwide population-based study:

Introduction: Multiple sclerosis (MS) is associated with reduced work capacity, but there is limited knowledge about MS patients’ sources of income. Objectives: The purpose of this study was to elucidate MS patients’ earnings and social benefits compared to those of the general population. Methods: From nationwide registers of all residents in Sweden aged 21–64 years in 2010 (n=5,291,764), those with an MS diagnosis (n=13,979) were compared to a propensity score matched reference group (n=69,895). Descriptive statistics and regression models were used to estimate the percentage difference between the MS patients and the matched references regarding the following annual incomes: earnings, disability pension, sickness absence, disability allowance, unemployment compensation and social assistance. Results: Both MS patients and the matched references received most of their income from earnings followed by disability pension and sickness absence. MS patients that were diagnosed in 2010 had 15% lower earnings than the matched references, while MS patients diagnosed before 2005 had 38% lower earnings. Corresponding figures regarding summed social benefits were 33% and 130% higher for MS patients, respectively. Conclusion: The results indicate that MS patients are overrepresented, in relative and absolute terms, regarding health-related benefits and have lower levels of earnings. However, the redistributing welfare systems appear to financially compensate the MS patients considerably.