Maria-Pia Hergens

Swedish Moist Snuff and Myocardial Infarction Among Men

Background: Previous studies have provided inconsistent results on possible increased risk of cardiovascular disease with the use of smokeless tobacco. The aim of this study was to assess whether long-term use of Swedish moist snuff (widely used among Swedish men) increases the risk of acute myocardial infarction. Methods: This case-control study was conducted in 2 Swedish counties. We identified 1760 men, age 45–70 years, who had a myocardial infarction in 1992–1994. We randomly selected male controls from the study base after stratification for age and hospital catchment area. Information about snuff consumption, smoking history, hypertension, and other factors was obtained by mailed questionnaire and medical examination. The participation rate was 77% among cases and 78% among controls, with tobacco use data available for 1432 cases and 1810 controls. Results: After adjustment for age, hospital catchment area, and smoking, the relative risk of first acute myocardial infarction was 1.1 (95% confidence interval = 0.8–1.5) for former snuff users and 1.0 (0.8–1.3) for current snuff users. Analyses limited to either nonfatal or fatal cases did not change the results. Among the controls, the consumption of smokeless tobacco was strongly associated with certain risk factors for myocardial infarction such as smoking, hypertension, and high body mass index. Conclusion: The hypothesis that smokeless tobacco increases the risk for myocardial infarction is not supported in the present study.

Long-term use of Swedish moist snuff and the risk of myocardial infarction amongst men

Background.  The scientific evidence on cardiovascular risks associated with long‐term use of snuff is limited and inconclusive. The use of this smokeless tobacco has increased in recent decades, and adverse health effects associated with snuff use could be of great public health concern.

Smokeless tobacco and the risk of stroke

Background: In Sweden, use of smokeless tobacco (oral moist snuff) is common among adult men. Research on cerebrovascular effects associated with long-term use of snuff is limited and inconclusive. We aimed to study whether long-term use of snuff affects the risk of stroke. Methods: Information on tobacco use was collected by questionnaire among Swedish construction workers attending health check-ups between 1978 and 1993. In total, 118,465 never-smoking men without a history of stroke were followed through 2003. We used the Inpatient Register and Causes of Death Register to identify subsequent morbidity and mortality from stroke and its subtypes (ischemic, hemorrhagic, and unspecified stroke). Relative risk estimates were derived from Cox proportional hazards regression model. Results: Almost 30% of the nonsmoking men had ever used snuff. Overall, 3248 cases of stroke were identified during follow-up. Compared with nonusers of tobacco, the multivariable-adjusted relative risks for ever-users of snuff were 1.02 (95% confidence interval; 0.92–1.13) for all cases and 1.27 (0.92–1.76) for fatal cases. Further analyses on subtypes of stroke revealed an increased risk of fatal ischemic stroke associated with current snuff use (1.72; 1.06–2.78), whereas no increased risk was noted for hemorrhagic stroke. Conclusion: Snuff use may elevate the risk of fatal stroke, and particularly of fatal ischemic stroke.

Risk of hypertension amongst Swedish male snuff users: a prospective study.

Background.  The scientific evidence on whether long‐term use of snuff is associated with high blood pressure is limited, inconsistent and based only on cross‐sectional data.

Blood pressure, body size and prostate cancer risk in the Swedish Construction Workers cohort.

Data from prospective studies on blood pressure and prostate cancer risk are limited, and results are inconclusive. Baseline measurements of height, weight and blood pressure were available in 336,159 men in the Swedish Construction Workers cohort. During an average of 22.2 years of follow‐up, 10,002 incident cases and 2,601 fatal cases of prostate cancer were identified in National registers. For 5,219 cases, tumor characteristics were available; 2,817 tumors were classified as nonaggressive and 2,402 as aggressive. Relative risks of disease were estimated from Cox regression models, using attained age as time‐scale, and adjusting for birth year, smoking status and body mass index (BMI). Top compared to bottom quintile level of systolic or diastolic blood pressure was associated with a significant 15–20% decreased risk of incident prostate cancer (p for trend: systolic < 0.0001, diastolic = 0.3), but blood pressure was not significantly associated with risk of fatal prostate cancer. BMI was not associated with prostate cancer incidence, but was positively associated with fatal prostate cancer; men in the top quintile had a 30% increased risk (p for trend = 0.0004). The associations between blood pressure and BMI and nonaggressive tumors were similar to those of incident prostate cancer, and associations with aggressive tumors were similar to those of fatal prostate cancer. Data from our study suggest that hypertension is associated with a decreased risk of incident prostate cancer, but the explanation for this finding is unclear. Our study support a positive association between overweight and risk of fatal prostate cancer.

Smokeless tobacco (snus) and risk of heart failure: results from two Swedish cohorts

Background: Oral moist snuff (snus) is discussed as a safer alternative to smoking, and its use is increasing. Based on its documented effect on blood pressure, we hypothesized that use of snus increases the risk of heart failure. Design: Two independent Swedish prospective cohorts; the Uppsala Longitudinal Study of Adult Men (ULSAM), a community-based sample of 1076 elderly men, and the Construction Workers Cohort (CWC), a sample of 118,425 never-smoking male construction workers. Methods: Cox proportional hazards models were used to investigate possible associations of snus use with risk of a first hospitalization for heart failure. Results: In ULSAM, 95 men were hospitalized for heart failure, during a median follow up of 8.9 years. In a model adjusted for established risk factors including past and present smoking exposure, current snus use was associated with a higher risk of heart failure [hazard ratio (HR) 2.08, 95% confidence interval (CI) 1.03⊟4.22] relative to non-use. Snus use was particularly associated with risk of non-ischaemic heart failure (HR 2.55, 95% CI 1.12⊟5.82). In CWC, 545 men were hospitalized for heart failure, during a median follow up of 18 years. In multivariable-adjusted models, current snus use was moderately associated with a higher risk of heart failure (HR 1.28, 95% CI 1.00⊟1.64) and non-ischaemic heart failure (HR 1.28, 95% CI 0.97⊟1.68) relative to never tobacco use. Conclusion: Data from two independent cohorts suggest that use of snus may be associated with a higher risk of heart failure.

Tick borne encephalitis (TBE)-vaccination coverage and analysis of variables associated with vaccination, Sweden

To estimate the tick borne encephalitis (TBE)-vaccination coverage in the greater Stockholm region, we sent a questionnaire to a randomized sample of 8000 individuals in 2013. Fifty-three percent of all respondents (n=4307) reported being vaccinated against TBE at least once. Reasons for not vaccinating included: no perceived risk (28.6%), too expensive (25.6%), did not have the time or opportunity (23%) and worried about vaccine side-effects (20.5%). Multiple logistic regression revealed that the probability of being vaccinated was higher among those who reported ≥2 weeks outdoor exposure in a known high risk area (OR 4.13 95% CI 3.54-4.81) and in individuals ≥60 years of age compared to all other age groups (OR 0.67 95% CI 0.55-0.81). A high net household income was associated with a higher probability of being vaccinated (OR 2.10 95% CI 1.6-2.73). Being born outside Europe was negatively correlated (OR 0.57 95% CI 0.39-0.83). Based on our findings the estimated TBE-incidence in the unvaccinated regional population was 8.5-12/100,000 which is comparable with high endemic areas as the Baltic region and Central Europe. We suggest targeted vaccination and reimbursement strategies in high-endemic areas of Sweden. Our results indicate a need for improved public information about TBE.

Use of Scandinavian Moist Smokeless Tobacco (Snus) and the Risk of Atrial Fibrillation.

Background: Snus is a smokeless tobacco product, widely used among Swedish men and increasingly so elsewhere. There is debate as to whether snus is an acceptable “harm-reduction” tobacco product. Since snus use delivers a dose of nicotine equivalent to cigarettes, and has been implicated in cardiac arrhythmia because of associations with sudden cardiovascular death, a relation with atrial fibrillation is plausible and important to investigate. Methods: To assess the relation between use of snus and risk of atrial fibrillation, we carried out a pooled analysis of 7 prospective Swedish cohort studies. In total, 274,882 men, recruited between 1978 and 2004, were followed via the National Patient Register for atrial fibrillation. Primary analyses were restricted to 127,907 never-smokers. Relative risks were estimated using Cox proportional hazard regression. Results: The prevalence of snus use was 25% among never-smokers. During follow-up, 3,069 cases of atrial fibrillation were identified. The pooled relative risk of atrial fibrillation was 1.07 (95% confidence interval = 0.97–1.19) in current snus users, compared with nonusers. Conclusion: Findings from this large national pooling project indicate that snus use is unlikely to confer any important increase in risk of atrial fibrillation.

Weight gain and incident obesity among male snus users

BackgroundSnus is a moist smokeless tobacco product which has recently reached beyond its original market of Scandinavia. Snus is now being increasingly used in both the United States and South Africa. The effect of snus use on weight is unknown. This study has therefore investigated the relationship between the use of snus, weight gain (≥5%) and the incidence of obesity (body mass index ≥30 kg/m2).MethodsThe study participants (n = 9,954 males living in Stockholm County, Sweden) were recruited in 2002 and reassessed in 2007. Tobacco use was categorized according to information obtained in both the baseline and follow-up surveys. Outcomes were assessed by comparing self-reported weight and body mass index between the baseline and follow-up surveys.ResultsStable current snus use (according to both surveys), compared to never having used any kind of tobacco, seemed to be associated with both weight gain (odds ratio = 1.31, 95% confidence interval: 1.04-1.65) and incident obesity (odds ratio = 1.93, 95% confidence interval: 1.13-3.30) after adjustment for age, baseline weight, alcohol consumption, physical activity, education, consumption of fruit and berries, and the frequency of having breakfast. No associations with incident obesity or weight gain were seen for stable former users of snus (according to both surveys) or among men who quit or began using snus during follow-up.ConclusionsThese data suggest that the use of snus is moderately associated with weight gain and incident obesity among men.

Barriers to Trace-back in a Salad-associated EHEC Outbreak, Sweden, June 2013.

In June-July 2013, six counties notified the Swedish Institute for Communicable Disease Control of enterohaemorrhagic E.coli (EHEC) infections among attendees at a hotel in Dalarna, Sweden. An outbreak control team investigated to identify the source and implement control measures. We included individuals who attended the hotel between June 19th-25th in a cohort. We asked them about animal contact, swimming, and consumption of food items during this time using a questionnaire. A confirmed case was an EHEC O157:H7 outbreak strain positive individual who developed abdominal pain or diarrhoea between June 20th-July 2nd. We described the outbreak in time, place and person, calculated risk ratios (RR) and 95% confidence intervals (CI). We investigated the kitchen, tested and traced back implicated food items. 172 individuals responded. We identified 19 confirmed cases (Median age: 17 years, 64% female) with symptom onset between June 22nd-27th. Eating green salad on June 20th was associated with illness (RR:3.7;CI:1.3–11). The kitchen mixed green salads without records and destroyed leftovers immediately. Hence we could not conduct trace-back or obtain microbiological confirmation. Green salad contaminated before entering the kitchen was the likely outbreak source. We recommended early collaboration with food agencies and better restaurant records to facilitate future investigations.