OBJECTIVE: To assess the risk of invasive breast cancer associated with total and beverage-specific alcohol consumption and to evaluate whether dietary and nondietary factors modify the association. DATA SOURCES: We included in these analyses 6 prospective studies that had at least 200 incident breast cancer cases, assessed long-term intake of food and nutrients, and used a validated diet assessment instrument. The studies were conducted in Canada, the Netherlands, Sweden, and the United States. Alcohol intake was estimated by food frequency questionnaires in each study. The studies included a total of 322647 women evaluated for up to 11 years, including 4335 participants with a diagnosis of incident invasive breast cancer. DATA EXTRACTION: Pooled analysis of primary data using analyses consistent with each study's original design and the random-effects model for the overall pooled analyses. DATA SYNTHESIS: For alcohol intakes less than 60 g/d (reported by >99% of participants), risk increased linearly with increasing intake; the pooled multivariate relative risk for an increment of 10 g/d of alcohol (about 0.75-1 drink) was 1.09 (95% confidence interval [CI], 1.04-1.13; P for heterogeneity among studies, .71). The multivariate-adjusted relative risk for total alcohol intakes of 30 to less than 60 g/d (about 2-5 drinks) vs nondrinkers was 1.41 (95% CI, 1.18-1.69). Limited data suggested that alcohol intakes of at least 60 g/d were not associated with further increased risk. The specific type of alcoholic beverage did not strongly influence risk estimates. The association between alcohol intake and breast cancer was not modified by other factors. CONCLUSIONS: Alcohol consumption is associated with a linear increase in breast cancer incidence in women over the range of consumption reported by most women. Among women who consume alcohol regularly, reducing alcohol consumption is a potential means to reduce breast cancer risk.
Comment In: JAMA. 1998 Oct 7;280(13):1138-99777807
BACKGROUND: The prenatal period has been suggested to be important for future cancer risk. Conditions in utero are also important for the development of the kidney, and birth weight, a marker of fetal nutrition and growth, is linearly correlated with the number of nephrons and the structural and functional unit of the kidney. An association between birth weight and renal cell cancer, the major form of kidney cancer, is biologically plausible, but has never been studied. METHODS: We conducted a population-based, case-controlled study in Sweden of men and women aged 20 to 79 years. We collected self-reported information on categories of birth weight from 648 patients with newly diagnosed renal cell cancer and from 900 frequency-matched control subjects. We used unconditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs) as estimates of the relative risks. RESULTS: An increased risk of renal cell cancer was observed among men with a birth weight of > or =3500 g (adjusted OR = 1.3, 95% CI, 1.0 to 1.8) compared with men with a birth weight between 3000 and 3499 g, especially in the subgroup without hypertension or diabetes (adjusted OR = 1.8, 95% CI, 1.2 to 2.6). No clear association among men with a birth weight
The impact of multiple healthy lifestyle factors on survival time is unclear.
The aim of this study was to examine differences in survival time associated with a healthy lifestyle versus a less healthy lifestyle.
This study consisted of 33 454 men (Cohort of Swedish Men) and 30 639 women (Swedish Mammography Cohort) aged 45-83 years and free of cancer and cardiovascular disease at baseline. The healthy lifestyle factors included the following: (i) nonsmoking; (ii) physical activity at least 150 min per week; (iii) alcohol consumption of 0-14 drinks per week; (iv) and healthy diet defined as a modified Dietary Approaches to Stop Hypertension Diet score above the median. Cox proportional hazards regression models and Laplace regression were used to estimate, respectively, hazard ratios of all-cause mortality and differences in survival time.
During follow-up from 1998 through 2014, 8630 deaths amongst men and 6730 deaths amongst women were ascertained through linkage to the Swedish Cause of Death Register. Each of the four healthy lifestyle factors was inversely associated with all-cause mortality and increased survival time. Compared with individuals with no or one healthy lifestyle factor, the multivariable hazard ratios of all-cause mortality for individuals with all four health behaviours were 0.47 (95% 95% confidence interval [CI]: 0.44-0.51) in men and 0.39 (95% CI: 0.35-0.44) in women. This corresponded to a difference in survival time of 4.1 (95% CI: 3.6-4.6) years in men and 4.9 (95% CI: 4.3-5.6) years in women.
Adopting healthy lifestyle behaviours may markedly increase lifespan.
To determine the relationships among nutrients intake, bone mass, and bone turnover in women we have investigated these issues in a population-based, cross-sectional, observational study in one county in central Sweden. A total of 175 women aged 28-74 at entry to the study were included. Dietary assessment was made by both a semiquantitative food frequency questionnaire and by four 1-week dietary records. Dual energy X-ray absorptiometry was performed at five sites: total body, L2-L4 region of the lumbar spine, and three regions of the proximal femur. Serum concentrations of osteocalcin (an osteoblast-specific protein reflecting bone turnover) were measured by a radioimmunoassay. Linear regression models, with adjustment for possible confounding factors were used for statistical analyses. A weak positive association was found between dietary calcium intake as calculated from the semiquantitative food frequency questionnaire and total body bone mineral density (BMD) among premenopausal women. No association emerged between dietary calcium intake and site-specific bone mass, i.e., lumbar spine and femoral neck, nor was an association found between dietary calcium intake and serum osteocalcin. BMD at some of the measured sites was positively associated with protein and carbohydrates and negatively associated with dietary fat. In no previous studies of diet and bone mass have dietary habits been ascertained so carefully and the results adjusted for possible confounding factors. Neither of the two methods of dietary assessment used in this study revealed any effect of calcium intake on BMD at fracture-relevant sites among these healthy, mostly middle-aged women.(ABSTRACT TRUNCATED AT 250 WORDS)
The incidence of adenocarcinoma of the oesophagus has increased rapidly in recent decades. In order to appreciate the potential for prevention by means of dietary modification, we estimated the aetiological fractions and the increments in absolute risk attributable to low intake of fruit and vegetables for adenocarcinoma and squamous cell carcinoma of the oesophagus and for adenocarcinoma of the gastroesophageal junction. We conducted a nationwide population-based case-control study in Sweden, with participation of 608 cases and 815 controls. We used unconditional logistic regression to estimate relative risks, from which we calculated aetiological fractions. Individuals in the highest exposure quartile (median 4.8 servings/day) versus the lowest (median 1.5 servings/day) showed approximately 50% lower risk of oesophageal adenocarcinoma and 40% lower risk of oesophageal squamous cell carcinoma, but no risk reduction for gastric cardia adenocarcinoma. Approximately 20% of oesophageal adenocarcinoma, and likewise squamous cell carcinoma, in Sweden was attributed to consuming less than three servings of fruit and vegetables per day. A very large number of individuals (over 25,000) would need to increase their fruit and vegetable consumption moderately in order to prevent one oesophageal cancer per year. Moderate relative risk reductions translate into weak absolute risk reductions for oesophageal cancers in Sweden.
Persistent organochlorines (POCs), such as polychlorinated biphenyls (PCBs) and DDT, are present at relatively high concentrations in food and show estrogenic, anti-estrogenic or anti-androgenic activity in biological test systems. Because bone mineral density (BMD) in men is influenced by sex hormones, we looked for associations between BMD and serum concentrations of POCs in 115 men (mean age 63 years, range 40-75 years) from the general Swedish population. Ten PCB congeners, five DDT isomers, hexachlorobenzene, three hexachlorocyclohexane isomers, trans-nonachlor and oxychlordane were analyzed by gas chromatography. Quantitative bone measurements were performed by dual-energy X-ray absorptiometry at three sites: whole body, the L2-L4 region of the lumbar spine, and the neck region of the proximal femur, as well as by quantitative ultrasound on the left os calcis (broadband ultrasound attenuation (BUA) and speed of sound (SOS)). After adjustment for confounding factors in linear regression analyses we found no strong association between serum concentrations of single POCs and the five BMD and ultrasound variables. When POCs were grouped according to hormonal activity (estrogenic, anti-estrogenic, anti-androgenic) and the study subjects were divided into organochlorine concentration quartiles, a weak association was indicated between increased serum concentrations of p,p'-DDE (antiandrogenic) and decreased BMD, BUA and SOS. This may suggest that p,p'-DDE could cause negative effects on bone density, but the findings might also be due to chance since multiple comparisons were made in the statistical analysis. Overall our results do not suggest that the studied POCs caused major effects on bone density in our study group.
There is a great need for simple means of identifying persons at low risk of developing osteoporosis, in order to exclude them from screening with bone mineral measurements, since this procedure is too expensive and time-consuming for general use in the unselected population. We have determined the relationships between body measure (weight, height, body mass index, lean tissue mass, fat mass, waist-to-hip ratio) and bone mineral density (BMD) in 175 women of ages 28-74 years in a cross-sectional study in a county in central Sweden. Dual-energy X-ray absorptiometry was performed at three sites: total body, L2-4 region of lumbar spine, and neck region of the proximal femur. Using multiple linear regression models, the relationship between the dependent variable, BMD, and each of the body measures was determined, with adjustment for confounding factors. Weight alone, in a multivariate model, explained 28%, 21% and 15% of the variance in BMD of total body, at the lumbar spine and at the femoral neck according to these models. The WHO definition of osteopenia was used to dichotomize BMD, which made it possible, in multivariate logistic regression models, to estimate the risk of osteopenia with different body measures categorized into tertiles. Weight of over 71 kg was associated with a very low risk of being osteopenic compared with women weighing less than 64 kg, with odds ratios (OR) of 0.01 (95% confidence interval (CI) 0.00-0.09), 0.06 (CI 0.02-0.22) and 0.13 (CI 0.04-0.42) for osteopenia of total body, lumbar spine and femoral neck, respectively. Furthermore a sensitivity/specificity analysis revealed that, in this population, a woman weighing over 70 kg is not likely to have osteoporosis. Test specifics of a weight under 70 kg for osteoporosis (BMD less than 2.5 SD compared with normal young women) of femoral neck among the postmenopausal women showed a sensitivity of 0.94, a specificity of 0.36, positive predictive value (PPV) of 0.21, and negative predictive value (NPV) of 0.97. Thus, exclusion of the 33% of women with the highest weight meant only that 3% of osteoporotic cases were missed. The corresponding figures for lumbar spine were sensitivity 0.89, specificity 0.38, PPV 0.33, and NPV 0.91. All women who were defined as being osteoporotic of total body weighed under 62 kg. When the intention was to identify those with osteopenia of total body among the postmenopausal women we attained a sensitivity of 0.92 and a NPV of 0.91 for a weight under 70 kg, whereas we found that weight could not be used as an exclusion criterion for osteopenia of femoral neck and lumbar spine. Our data thus indicate that weight could be used to exclude women from a screening program for postmenopausal osteoporosis.
BACKGROUND. In retrospective studies of dietary habits and breast cancer risk, recall bias is a concern since diet has been publicized as a cause of breast cancer. METHODS. In a case-control study of diet and breast cancer risk nested within a cohort of women screened with mammography, we contrasted answers to a retrospective dietary interview with answers to a dietary questionnaire which was filled out before any diagnostic procedures for breast cancer were undertaken. The source population was all women aged 40-74 in two counties in Sweden invited to mammographic screening and asked to fill out a questionnaire before the screening. Cases and controls were subsequently defined -- matched on age, county of residence, and time of mammography -- and approached for an interview. RESULTS. In all, 265 cases and 431 controls participated in the study. Means of frequencies differed between the agreement in the questionnaire's and the interview's classifications of study subjects into quartiles of monthly intake varied between 31 percent and 57 percent. Kappa statistics in all food groups were below 0.41. In a regression analysis, case subjects with low responses on the questionnaire about intake of meat, snacks, and coffee and tea gave higher responses on interview than did controls who had low questionnaire responses for these food groups. The reverse was also true: cases' responses that were high on the questionnaire were lower on interview for these food groups than were controls' responses. CONCLUSIONS. We found few signs of recall bias, and the few indications of a differential misclassification that we found were not in food groups that have been publicly discussed as causes of breast cancer.