Omid Beiki

Breast cancer incidence and case fatality among 4.7 million women in relation to social and ethnic background: a population-based cohort study

IntroductionIncidence of breast cancer is increasing around the world and it is still the leading cause of cancer mortality in low- and middle-income countries. We utilized Swedish nationwide registers to study breast cancer incidence and case fatality to disentangle the effect of socioeconomic position (SEP) and immigration from the trends in native Swedes.MethodsA nation-wide cohort of women in Sweden was followed between 1961 and 2007 and incidence rate ratio (IRR) and hazard ratio (HR) with 95% confidence intervals (CIs) were estimated using Poisson and Cox proportional regression models, respectively.ResultsIncidence continued to increase; however, it remained lower among immigrants (IRR = 0.88, 95% CI = 0.86 to 0.90) but not among immigrants daughters (IRR = 0.97, 95% CI = 0.94 to 1.01) compared to native Swedes. Case fatality decreased over the last decades and was similar in native Swedes and immigrants. However, case fatality was significantly 14% higher if cancer was diagnosed after age 50 and 20% higher if cancer was diagnosed in the most recent years among immigrants compared with native Swedes. Women with the highest SEP had significantly 20% to 30% higher incidence but had 30% to 40% lower case fatality compared with women with the lowest SEP irrespective of country of birth. Age at immigration and duration of residence significantly modified the incidence and case fatality.ConclusionsDisparities found in case fatality among immigrants by age, duration of residence, age at immigration and country of birth emphasize the importance of targeting interventions on women that are not likely to attend screenings or are not likely to adhere to the therapy suggested by physicians. The lower risk of breast cancer among immigrant women calls for more knowledge about how the lifestyle factors in these women differ from those with high risk, so that preventative measures may be implemented.

Incidence and case fatality after day 28 of first time myocardial infarction in Sweden 1987-2008.

Aims: We studied trends in first-time myocardial infarction (MI) incidence and case fatality after day 28 and to examine the role of sex, education as an indicator for socioeconomic position, and birth country on these events in Sweden. Methods and results: Nationwide cohort including 6,752,655 individuals aged 35–89 years living in Sweden between January 1987 and December 2008, of which, 6,464,968 individuals and 366,085 nonfatal first-time MI patients were classified according to their sex, birth country, and education and followed over two decades. Main outcome measures: Incidence and case-fatality rate after day 28 of first-time MI and their trends. A decreasing trend for first-time MI incidence and case fatality after day 28 for both sexes regardless of birth country was observed (p-trend<0.0001). The trend was, however, less pronounced among female and foreign-born. Men had higher incidence than women (incidence rate ratio, IRR 2.09, 95% CI 2.08–2.11). Men born in Southern and Western Asia had 50% (95% CI 40−60%) higher risk than men born in Sweden. Incidence was 50–80% higher in the least educated irrespective of sex and birth country (p-trend<0.0001). This association was stronger for female and foreign-born. We observed a 15% higher case fatality after day 28 among men than women (hazard ratio, HR 1.15, 95% CI 1.13–1.17) and 20−40% lower case fatality after day 28 among patients with no diabetes. Low education was associated with 50% higher case fatality after day 28 regardless of sex and birth country (p-trend <0.0001). Conclusion: Although incidence of, and fatality after, first-time MI continued to decrease, low socioeconomic position, independent of birth country and sex, remained an important risk indicator for both events.

Subtype-Specific Risk of Testicular Tumors among Immigrants and Their Descendants in Sweden, 1960 to 2007

Background: Testicular cancer is the most common cancer among young male adults in several populations. We compared subtype-specific risk of testicular cancer among migrants and their descendants to that of Swedish-born men to elucidate importance of genetic and environmental factors in testicular cancer etiology and the potential timing of exposures. Methods: We followed a nationwide cohort of 3.6 million men ages 15 to 54 years between 1960 and 2007 through linkage between Swedish National Registers. Incidence rate ratio (IRR) adjusted for age and calendar year with 95% confidence intervals (CI) was estimated using Poisson regression. Results: A total of 5,801 cases of testicular cancer occurred during 80 million person-years of follow-up. Compared with Swedish-born men, first-generation immigrants from low-risk countries had a lower risk (IRR, 0.43; 95% CI, 0.38-0.49) and first-generation immigrants from high-risk countries had a higher risk (IRR, 1.61; 95% CI, 1.42-1.83) of testicular cancer. The risk among first-generation immigrants varied remarkably by birthplace, reflecting the risk in their countries of birth. The risk of seminomas was statistically significantly modified by age at immigration and duration of residence among immigrants born in high-risk areas. We observed a statistically significantly convergence of risk among second-generation immigrants toward the risk in Sweden (IRR, 1.02; 95% CI, 0.93-1.12). The risk among second-generation immigrants was not affected by the duration of stay of their mothers in Sweden before pregnancy. Conclusions: Our study provides evidence that life-style and environmental factors play an important role in the etiology of testicular cancer. Cancer Epidemiol Biomarkers Prev; 19(4); 1053–65. ©2010 AACR.

Parental educational level and injury incidence and mortality among foreign-born children: a cohort study with 46 years follow-up

Abstract: Background: Injury risk during childhood and adolescence vary depending on socio-economic factors. The aim of this study was to study if the risk of fatal and non-fatal unintentional injuries among foreign-born children was similar across parental educational level or not. Methods: In this retrospective cohort study we followed 907,335 children between 1961 and 2007 in Sweden. We established the cohort by linkage between Swedish national registers including cause of death register and in-patient register, through unique Personal Identification Numbers. The main exposure variable was parental (maternal and paternal) educational level. The cohorts was followed from start date of follow-up period, or date of birth whichever occurred last, until exit date from the cohort, which was date of hospitalization or death due to unintentional injury, first emigration, death due to other causes than injury or end of follow-up, whichever came first. We calculated hazard ratios (HR) with 95% confidence intervals (95% CI) by Cox proportional hazards regression models. Results: Overall, we found 705 and 78,182 cases of death and hospitalization due to unintentional injuries, respectively. Risk of death and hospitalization due to unintentional injuries was statistically significantly 1.48 (95% CI: 1.24-1.78) and 1.10 (95% CI: 1.08-1.12) times higher among children with lowest parental educational level (9 years and shorter years of study) compared to children with highest parental educational level (+13 years of study). We found similar results when stratified our study group by sex of children, by maternal and paternal educational level separately, and injury type (traffic-related, fall, poisoning, burn and drowning). Conclusions: It seems injury prevention work against unintentional injuries is less effective among children with low parental education compared with those with higher parental education. We recommend designing specific preventive interventions aiming at children with low parental education.

Risk of prostate cancer among Swedish‐born and foreign‐born men in Sweden, 1961–2004

To elucidate the importance of environmental and genetic factors in prostate cancer etiology, we compared the risk of prostate cancer among foreign‐born men to that of Swedish‐born men in Sweden and to that in the country of origin. We estimated rate ratios (RRs) with 95% confidence intervals (CIs) adjusted for age, calendar period of year and education using Poisson regression in a cohort of 3.8 million men aged 45 years and older between 1961 and 2004. During the 45 years of follow‐up, 8,244 and 187,675 cases of prostate cancer occurred among foreign‐born and Swedish‐born men, respectively. Overall, foreign‐born men had a significantly 40% decreased risk of prostate cancer compared to Swedish‐born men (RR = 0.62, 95% CI = 0.61–0.63). Men born in Middle Africa and in the Caribbean had an increased risk (RR = 1.89, 95% CI = 0.95–3.78 and RR = 1.24, 95% CI = 0.71–2.19, respectively). The overall risk in both strata of duration of residence or age at immigration was lower among immigrants compared to Swedish‐born men. After additional adjustment for birthplace and age at immigration, although the risk remained lower among immigrants compared to Swedish‐born, but it was increased among immigrants who stayed 35 years and longer compared to those who stayed shorter (RR = 1.33, 95% CI = 1.21–1.46). Both environmental and genetic factors seem to be involved in the etiology of prostate cancer. Duration of residence was an important factor affecting the risk among immigrants. Studies focusing on the etiology of prostate cancer specifically in African immigrants and their descendants and increasing preventive and diagnostic activities on old immigrants are recommended.

An assessment of suicide attempts by self-poisoning in the west of Iran

Intentional self-poisoning that is widely used all over the world is one of the most common methods of suicide. This study aim was to determine the rate of attempted intentional self-poisoning and to identify high risk persons in the west of Iran (Kermanshah). A total of 3138 people (1279 M and 1859 F) studied. The average annual rate of suicide in Kermanshah was 153 persons per 100xa0000 people. The most number of attempted intentional self-poisoning (55.5%) were in the 20-29 year age group. The most popular toxic substances for self-poisoning were drugs (71%) and oil and fuels (15%), respectively. The most number of intentional self-poisoning suicides are attempted by drugs. By considering the high rate of intentional self-poisoning, low age of suicide attempts and also its high mortality rate in Kermanshah, it is necessary to stop the opportunity to buy over-the-counter (OTC) drugs, especially those being most misused.

Challenges to promoting population-based cancer registration in Iran: a workshop report.

In December 2011, the Cancer Research Centre of the Cancer Institute of Iran sponsored a 3-day workshop on Cancer Registration Principle and Challenges in Iran, which convened cancer registry experts. The objectives of the workshop were: to introduce standard cancer registration, to review the policy and procedure of cancer registration in Iran, and to review the best practices in the cancer registries in Iran. Challenges to cancer registration were discussed and recommendations were developed. The workshop was evaluated by participants for better organization of subsequent workshops. The objective of publication of this report is that based on Cancer in 5 Continents, many low- or middle-income countries do not meet the criteria for a standard population-based cancer registry (PBCR); on the other hand cancer is the most important cause of mortality and the essential part of any cancer control program is the cancer registry. Therefore this report focuses on problems and challenges of PBCR and provides recommendations which might help other developing countries to decrease their PBCR defects.

Downward trend in the risk of second myocardial infarction in Sweden, 1987–2007: breakdown by socioeconomic position, gender, and country of birth

Background Second myocardial infarction (SMI) is a significant health problem. There are no nationwide studies on SMI among foreign-born populations that include detailed information about country of birth. Design Nationwide cohort study of 331,748 men and 186,755 women aged 30–84, living in Sweden, and diagnosed with first myocardial infarction (FMI) between January 1987 and December 2007. Methods Trends in, and risk of, SMI after day 28 of FMI association with gender, educational level, and country of birth were analysed. A hazard ratio (HR) with a 95% confidence interval (CI) yielded a risk estimate of SMI among FMI patients based on the Cox proportional hazard model. Results Men had a higher risk of SMI than women (HR 1.14, 95% CI 1.12–1.55) with a downward trend over time, regardless of country of birth (p-trendu2009<0.0001). Low educational level increased the HR of SMI irrespective of gender or country of birth. Foreign-born men and women had a slightly increased HR than Sweden-born. Men born in India, Palestine, Uganda, Algeria, and Tunisia and women born in India, Palestine, and Lebanon had approximately a 2-fold risk. Men born in the Netherlands had the lowest risk (HR 0.65, 95% CI 0.44–0.94). Foreign-born who had lived in Sweden for less than 35 years had a higher risk than those that had lived there for 35 years or longer. Conclusions Although the risk of SMI continued to decrease over time, low socioeconomic position independent of country of birth and gender remained an important risk indicator deserving further attention.

Short and Long Term Mortality after Coronary Artery Bypass Grafting (CABG) Is Influenced by Socioeconomic Position but Not by Migration Status in Sweden, 1995–2007

Background There are no nationwide studies on mortality after coronary artery bypass grafting (CABG) among foreign-born populations that include detailed information about country of birth and information about socioeconomic position. The objective was to investigate the risk of mortality after CABG considering socioeconomic position, sex and country of birth. Material and Methods We included all 72 333 patients undergoing a first isolated CABG in Sweden, during 1995 - 2007 of whom 12.7% were foreign-born. The patients were classified according to educational level, sex, and country of birth and were followed up to December 2007. We estimated the risk of short and long term mortality after CABG in a multivariable model adjusted for age, calendar year of surgery, diabetes, educational level, and waiting time for surgery. Hazard ratios (HR) with 95% confidence intervals (CI) were calculated based on the Cox proportional hazard model. Findings There were 15,284 deaths during the follow-up, 10.4% of whom were foreign-born. The foreign-born patients were 3 to 4 years younger than Sweden-born patients at the time of CABG surgery. There were no significant differences in overall early or late mortality between foreign-born and Sweden-born men and women after CABG. All-cause mortality differed in between regions and was highest in foreign-born men from Eastern Africa (HR 3.80, 95% CI 1.58–9.17), China (HR 3.61, 95% CI 1.50–8.69), and in Chile (HR 2.12, 95% CI 1.01–4.47). Patients with low level of education had worse survival compared to those with longer than 12 years of education irrespective of sex and country of birth. This difference was more pronounced among foreign-born women (HR 1.50, 95% CI 1.00–2.33). Conclusion This national study showed higher CABG mortality in patients from lower socioeconomic position. Early and late mortality did not differ after isolated CABG in foreign-born and Sweden-born patients.

Treatment with disease-modifying drugs for people with a first clinical attack suggestive of multiple sclerosis.

BACKGROUNDnThe treatment of multiple sclerosis has changed over the last 20 years. The advent of disease-modifying drugs in the mid-1990s heralded a period of rapid progress in the understanding and management of multiple sclerosis. With the support of magnetic resonance imaging early diagnosis is possible, enabling treatment initiation at the time of the first clinical attack. As most of the disease-modifying drugs are associated with adverse events, patients and clinicians need to weigh the benefit and safety of the various early treatment options before taking informed decisions.nnnOBJECTIVESn1. to estimate the benefit and safety of disease-modifying drugs that have been evaluated in all studies (randomised or non-randomised) for the treatment of a first clinical attack suggestive of MS compared either with placebo or no treatment;2. to assess the relative efficacy and safety of disease-modifying drugs according to their benefit and safety;3. to estimate the benefit and safety of disease-modifying drugs that have been evaluated in all studies (randomised or non-randomised) for treatment started after a first attack (early treatment) compared with treatment started after a second attack or at another later time point (delayed treatment).nnnSEARCH METHODSnWe searched the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Group Trials Register, MEDLINE, Embase, CINAHL, LILACS, clinicaltrials.gov, the WHO trials registry, and US Food and Drug Administration (FDA) reports, and searched for unpublished studies (until December 2016).nnnSELECTION CRITERIAnWe included randomised and observational studies that evaluated one or more drugs as monotherapy in adult participants with a first clinical attack suggestive of MS. We considered evidence on alemtuzumab, azathioprine, cladribine, daclizumab, dimethyl fumarate, fingolimod, glatiramer acetate, immunoglobulins, interferon beta-1b, interferon beta-1a (Rebif®, Avonex®), laquinimod, mitoxantrone, natalizumab, ocrelizumab, pegylated interferon beta-1a, rituximab and teriflunomide.nnnDATA COLLECTION AND ANALYSISnTwo teams of three authors each independently selected studies and extracted data. The primary outcomes were disability-worsening, relapses, occurrence of at least one serious adverse event (AE) and withdrawing from the study or discontinuing the drug because of AEs. Time to conversion to clinically definite MS (CDMS) defined by Poser diagnostic criteria, and probability to discontinue the treatment or dropout for any reason were recorded as secondary outcomes. We synthesized study data using random-effects meta-analyses and performed indirect comparisons between drugs. We calculated odds ratios (OR) and hazard ratios (HR) along with relative 95% confidence intervals (CI) for all outcomes. We estimated the absolute effects only for primary outcomes. We evaluated the credibility of the evidence using the GRADE system.nnnMAIN RESULTSnWe included 10 randomised trials, eight open-label extension studies (OLEs) and four cohort studies published between 2010 and 2016. The overall risk of bias was high and the reporting of AEs was scarce. The quality of the evidence associated with the results ranges from low to very low. Early treatment versus placebo during the first 24 months follow-upThere was a small, non-significant advantage of early treatment compared with placebo in disability-worsening (6.4% fewer (13.9 fewer to 3 more) participants with disability-worsening with interferon beta-1a (Rebif®) or teriflunomide) and in relapses (10% fewer (20.3 fewer to 2.8 more) participants with relapses with teriflunomide). Early treatment was associated with 1.6% fewer participants with at least one serious AE (3 fewer to 0.2 more). Participants on early treatment were on average 4.6% times (0.3 fewer to 15.4 more) more likely to withdraw from the study due to AEs. This result was mostly driven by studies on interferon beta 1-b, glatiramer acetate and cladribine that were associated with significantly more withdrawals for AEs. Early treatment decreased the hazard of conversion to CDMS (HR 0.53, 95% CI 0.47 to 0.60). Comparing active interventions during the first 24 months follow-upIndirect comparison of interferon beta-1a (Rebif®) with teriflunomide did not show any difference on reducing disability-worsening (OR 0.84, 95% CI 0.43 to 1.66). We found no differences between the included drugs with respect to the hazard of conversion to CDMS. Interferon beta-1a (Rebif®) and teriflunomide were associated with fewer dropouts because of AEs compared with interferon beta-1b, cladribine and glatiramer acetate (ORs range between 0.03 and 0.29, with substantial uncertainty). Early versus delayed treatmentWe did not find evidence of differences between early and delayed treatments for disability-worsening at a maximum of five years follow-up (3% fewer participants with early treatment (15 fewer to 11.1 more)). There was important variability across interventions; early treatment with interferon beta-1b considerably reduced the odds of participants with disability-worsening during three and five years follow-up (OR 0.52, 95% CI 0.32 to 0.84 and OR 0.57, 95% CI 0.36 to 0.89). The early treatment group had 19.6% fewer participants with relapses (26.7 fewer to 12.7 fewer) compared to late treatment at a maximum of five years follow-up and early treatment decreased the hazard of conversion to CDMS at any follow-up up to 10 years (i.e. over five years follow-up HR 0.62, 95% CI 0.53 to 0.73). We did not draw any conclusions on long-term serious AEs or discontinuation due to AEs because of inadequacies in the available data both in the included OLEs and cohort studies.nnnAUTHORS CONCLUSIONSnVery low-quality evidence suggests a small and uncertain benefit with early treatment compared with placebo in reducing disability-worsening and relapses. The advantage of early treatment compared with delayed on disability-worsening was heterogeneous depending on the actual drug used and based on very low-quality evidence. Low-quality evidence suggests that the chances of relapse are less with early treatment compared with delayed. Early treatment reduced the hazard of conversion to CDMS compared either with placebo, no treatment or delayed treatment, both in short- and long-term follow-up. Low-quality evidence suggests that early treatment is associated with fewer participants with at least one serious AE compared with placebo. Very low-quality evidence suggests that, compared with placebo, early treatment leads to more withdrawals or treatment discontinuation due to AEs. Difference between drugs on short-term benefit and safety was uncertain because few studies and only indirect comparisons were available. Long-term safety of early treatment is uncertain because of inadequately reported or unavailable data.