Higher protein intake is associated with increased risk for incident end-stage renal disease among blacks with diabetes in the Southern Community Cohort Study.

BACKGROUND AND AIMS: Diabetes, a risk factor for end-stage renal disease (ESRD), is associated with impaired protein metabolism. We investigated whether protein intake is associated with ESRD and whether the risk is higher among blacks with diabetes. METHODS AND RESULTS: We conducted a nested case-control study of ESRD within the Southern Community Cohort Study, a prospective study of low-income blacks and whites in the southeastern US (2002-2009). Through 2012, 1057 incident ESRD cases were identified by linkage with the United States Renal Data System and matched to 3198 controls by age, sex, and race. Dietary intakes were assessed from a validated food frequency questionnaire at baseline. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed from logistic regression models that included matching variables, BMI, education, income, hypertension, total energy intake, and percent energy from saturated and polyunsaturated fatty acids. Mean (±SD) daily energy intake from protein was higher among ESRD cases than controls (15.7 ± 3.3 vs. 15.1 ± 3.1%, P < 0.0001). For a 1% increase in percent energy intake from protein, the adjusted ORs (95% CIs) for ESRD were 1.06 (1.02-1.10) for blacks with diabetes, 1.02 (0.98-1.06) for blacks without diabetes, 0.99 (0.90-1.09) for whites with diabetes and 0.94 (0.84-1.06) for whites without diabetes. Protein intake in g/kg/day was also associated with ESRD (4th vs. 1st quartile OR = 1.76; 95% CI: 1.17-2.65). CONCLUSION: Our results raise the possibility that among blacks with diabetes, increased dietary protein is associated with increased incidence of ESRD. Studies on how protein intake and metabolism affect ESRD are needed.

Intake of polyunsaturated fat in relation to mortality among statin users and non-users in the Southern Community Cohort Study.

BACKGROUND AND AIMS: Consumption of polyunsaturated fatty acids (PUFA), especially the n3-series, may protect against cardiovascular disease (CVD), but recent randomized studies have failed to demonstrate these benefits. One of the prevailing hypotheses is that PUFA intake may not confer benefits beyond those provided by statins, but studies comparing statin users to non-users with regard to effects of PUFA are lacking. METHODS AND RESULTS: Black and white men and women (n = 69,559) in the Southern Community Cohort Study were studied. Cox regression models adjusting for age, sex, race, BMI, recruitment site, education, income, smoking, diabetes, and dietary variables were used. RESULTS: At baseline the mean ± SD age was 52 ± 9 years, 60% of participants were women, 54% had hypertension and 16% used statins. We observed modest inverse associations between n3-PUFA and n6-PUFA intake with mortality among non-statin users but not among statin users. In adjusted analyses, the HRs (95% CIs) for all-cause mortality (6,396 deaths over a median of 6.4 years) comparing the highest to the lowest quintile were 0.90 (0.82-1.00) for n3-PUFA and 0.80 (0.70-0.92) for n6-PUFA among non-statin users, whereas they were 1.06 (0.87-1.28) and 0.96 (0.78-1.19) for n3-PUFA and n6-PUFA, respectively, among statin users. CONCLUSIONS: Our results suggest potential benefits of PUFA consumption on mortality which are only apparent in the absence of statin therapy. It seems prudent to consider the potential benefit of PUFA consumption in the primary prevention of CVD among patients who are not candidates for statin therapy but are at increased risk for CVD and mortality.

Maternal and cord blood hormone levels in the United States and China and the intrauterine origin of breast cancer.

BACKGROUND: Breast cancer is less common in China than in the United States and perinatal characteristics predict breast cancer risk in the offspring. We determined levels of pregnancy hormones in Boston and Shanghai to identify those possibly involved in the intrauterine origin of breast cancer. PARTICIPANTS AND METHODS: We compared maternal and cord blood levels of estradiol, estriol, testosterone, progesterone, prolactin, insulin-like growth factors (IGF) 1 and 2, insulin-like growth factor-binding protein 3, adiponectin and sex hormone-binding globulin (SHBG) in 241 Caucasian and 295 Chinese women. RESULTS: In both centers, hormone levels at the 16th were predictive of those at the 27th gestational week, but there was little correlation between maternal and cord blood levels. In cord blood, we found significantly (P < 0.01) higher levels of estradiol (44.2%), testosterone (54.5%), IGF-2 (22.7%) and strikingly SHBG (104.6%) in Shanghai women, whereas the opposite was true for IGF-1 (-36.8%). CONCLUSIONS: Taking into account the current understanding of the plausible biological role of the examined endocrine factors, those likely to be involved in the intrauterine origin of breast cancer are SHBG and IGF-2, with higher cord blood levels among Chinese, and IGF-1, with higher cord blood levels among Caucasian women.

Insulin-like growth factor levels in cord blood, birth weight and breast cancer risk.

Breast cancer incidence and birth weight are higher among Caucasian than Asian women, and birth size has been positively associated with breast cancer risk. Pregnancy hormone levels, however, have been generally lower in Caucasian than Asian women. We studied components of the insulin-like growth factor (IGF) system in cord blood from 92 singleton babies born in Boston, USA, and 110 born in Shanghai, China, in 1994-1995. Cord blood IGF-1 was significantly higher among Caucasian compared with Chinese babies (P<10(-6)). The opposite was noted for IGF-2 (P approximately 10(-4)). IGF-1 was significantly positively associated with birth weight and birth length in Boston, but not Shanghai. In contrast, stronger positive, though statistically non-significant, associations of IGF-2 with birth size were only evident in Shanghai. The associations of birth weight and birth length were positive and significant in taller women (for IGF-1 in Boston P approximately 0.003 and 0.03, respectively; for IGF-2 in Shanghai P approximately 0.05 and approximately 0.04, respectively), among whom maternal anthropometry does not exercise strong constraints in foetal growth. The documentation of higher cord blood levels of IGF-1, a principal growth hormone that does not cross the placenta, among Caucasian than in Asian newborns is concordant with breast cancer incidence in these populations.

Dietary vitamin D and cancers of the oral cavity and esophagus.

BACKGROUND: Data on the association between vitamin D and upper digestive tract neoplasms are limited. METHODS: In two case-control studies in Italy, we examined the relation between dietary vitamin D intake and squamous cell carcinoma of the esophagus (SCCE; 304 cases) and oral/pharyngeal cancer (804 cases). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by multiple logistic regression. RESULTS: Adjusted ORs for SCCE and oral/pharyngeal cancer were 0.58 (95% CI 0.39-0.86) and 0.76 (95% CI 0.60-0.94), respectively, for the highest tertile of vitamin D intake. Using a reference group of those in the highest tertile of vitamin D who were never/former smokers, ORs were 8.7 (95% CI 4.1-18.7) for SCCE and 10.4 (95% CI 6.9-15.5) for oral/pharyngeal cancer among heavy smokers in the lowest vitamin D tertile; similarly, compared with those in the highest tertile of vitamin D who drank <3 alcoholic drinks/day, corresponding ORs were 41.9 (95% CI 13.7-128.6) for SCCE and 8.5 (95% CI 5.7-12.5) for oral/pharyngeal cancer, among heavy alcohol drinkers in the lowest vitamin D tertile. CONCLUSION: We observed inverse associations between dietary vitamin D intake and risk of SCCE and, perhaps, oral/pharyngeal cancer, which were most pronounced among heavy current smokers and heavy consumers of alcohol.

Vitamin D intake and breast cancer risk: a case-control study in Italy.

BACKGROUND: Vitamin D has been suggested to play a protective role against several cancers, including breast cancer. PATIENTS AND METHODS: We used data from a case-control study conducted in Italy from 1991 to 1994 to study the relation between dietary intake of vitamin D and breast cancer risk. Subjects were 2569 women with incident, histologically confirmed breast cancer and 2588 hospital controls. Odds ratios (ORs) and 95% confidence intervals (CIs) according to deciles of vitamin D intake were estimated by multiple logistic regression models. RESULTS: After allowance for major risk factors for breast cancer and dietary covariates including calcium and energy intake, there was no association with vitamin D up to the seventh decile. Thereafter, the OR declined, so that the overall trend was statistically significantly inverse. The OR for subjects in the three highest deciles of consumption compared with those in the lowest ones combined was 0.79 (95% CI 0.70-0.90). Intake of vitamin D >3.57 microg or 143 IU appeared to have a protective effect against breast cancer. The inverse association was consistent across strata of menopausal status. CONCLUSIONS: This study adds to the existing evidence that vitamin D intake in inversely associated with breast cancer risk.

Dietary glycemic load and hepatocellular carcinoma with or without chronic hepatitis infection.

BACKGROUND: Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major risk factors for hepatocellular carcinoma (HCC). The association of diabetes mellitus with HCC suggests that dietary glycemic load (GL) may influence HCC risk. We have examined the association between dietary GL and HCC. PATIENTS AND METHODS: We conducted a hospital-based case-control study in Italy in 1999-2002, including 185 HCC cases and 412 controls who answered a validated food frequency questionnaire and provided blood samples. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were computed using unconditional multiple logistic regression. RESULTS: We observed a positive association between GL and HCC overall, with an OR of 3.02 (95% CI 1.49-6.12) for the highest quintile of GL compared with the lowest and a significant trend. The OR among HCC cases with evidence of chronic infection with HBV and/or HCV was 3.25 (95% CI 1.46-7.22), while the OR among those with no evidence of infection was 2.45 (95% CI 0.69-8.64), with no significant trend. The association was not explained by the presence of cirrhosis or diabetes. CONCLUSIONS: High dietary GL is associated with increased risk for HCC. The positive association was most pronounced among HCC cases with HBV and/or HCV markers.

History of breast-feeding in relation to breast cancer risk: a review of the epidemiologic literature.

The purpose of this review is to critically evaluate the collective epidemiologic evidence that a history of breast-feeding may decrease the risk of breast cancer. Original data for inclusion were identified through a MEDLINE(R) search of the English language literature from 1966 through 1998. To date, virtually all epidemiologic data regarding breast-feeding and breast cancer risk are derived from case-control studies, which vary according to classification of breast-feeding history. Overall, the evidence with respect to "ever" breast-feeding remains inconclusive, with results indicating either no association or a rather weak protective effect against breast cancer. An inverse association between increasing cumulative duration of breast-feeding and breast cancer risk among parous women has been reported in some, but not all, studies; the failure to detect an association in some Western populations may be due to the low prevalence of prolonged breast-feeding. It appears that the protective effect, if any, of long-term breast-feeding is stronger among, or confined to, premenopausal women. It has been hypothesized that an apparently protective effect of breast-feeding may be due to elevated breast cancer risk among women who discontinue breast-feeding or who take medication to suppress lactation; however, the evidence is limited and should be interpreted with caution. The biology underlying a protective effect of breast-feeding and why this should be restricted to premenopausal women remain unknown, although several mechanisms have been postulated (hormonal changes, such as reduced estrogen; removal of estrogens through breast fluid; excretion of carcinogens from breast tissue through breast-feeding; physical changes in the mammary epithelial cells, reflecting maximal differentiation; and delay of the re-establishment of ovulation). While breast-feeding is a potentially modifiable behavior, the practical implication of reduced breast cancer risk among premenopausal women with prolonged durations of breast-feeding may be of marginal importance, particularly in Western societies.

Intrauterine environment and breast cancer risk in women: a population-based study.

BACKGROUND: The established risk factors for female breast cancer, including nulliparity, age at first birth, age at menarche, and age at menopause, do not adequately explain the occurrence pattern of this cancer. Therefore, additional factors need to be considered to advance our understanding of the causes of breast cancer. Evidence obtained from animals and humans indicates that the perinatal period may be particularly important. Our earlier studies, based on a subsample of the present investigation, suggested that factors thought to be positively associated with estrogen levels during pregnancy are positively associated with breast cancer risk. However, the associated confidence intervals (CIs) were generally wide, indicating considerable variability in the data. PURPOSE: We studied a large number of incident breast cancer case patients and evaluated several perinatal variables in relation to breast cancer risk. These variables included some not previously studied, such as gestational age and neonatal jaundice. We also investigated twin membership as a predictor variable and death from breast cancer, in addition to occurrence of breast cancer, as an alternative outcome variable. METHODS: Birth records for all deliveries at five different hospitals in Sweden during the period from 1874 through 1961 were used to define a large cohort of women. Incident case patients with breast cancer in this cohort were ascertained through the National Cancer Registry or the Uppsala Regional Cancer Registry from 1958 through 1994. In a case-control study nested in the cohort, we abstracted data from birth records on 1068 women with incident breast cancer and on 2727 control subjects individually matched to the case patients on date of birth. We modeled the data through conditional logistic regression. All P values were derived from two-sided statistical tests. RESULTS: We found a markedly reduced risk for breast cancer in women whose mothers had pregnancy toxemia (odds ratio [OR] = 0.41; 95% CI = 0.22-0.79) and an excess risk on women who had neonatal jaundice (OR = 2.16; 95% CI = 1.27-3.67) or who were born before 33 weeks of gestation (OR = 3.96; 95% CI = 1.45-10.81). Compared with the risk for breast cancer in the singleton, the risk for breast cancer in dizygotic twins was increased, although this increase was not statistically significant (OR = 1.72; 95% CI = 0.92-3.20). There was no evidence in these data for a statistically significant or substantial association of breast cancer risk with birth size indicators (i.e., weight and length at birth and placental weight). CONCLUSION AND IMPLICATIONS: Because pregnancy toxemia is associated with low levels of estrogens and neonatal jaundice, severe prematurity, and dizygotic twins with high levels of estrogens, our findings suggest that estrogens and other hormonal factors, known to influence breast cancer risk in the adult, may also play a critical role during the intrauterine period.

Nationwide study of cancer risk among hip replacement patients in Sweden.

BACKGROUND: Orthopedic implants and their fixatives contain materials with carcinogenic potential. Whether these implants are linked to subsequent cancer development remains unknown, mainly because large-scale, long-term follow-up data are scarce. METHODS: We conducted a nationwide cohort study in Sweden to examine cancer incidence among 116,727 patients who underwent hip replacement surgery during the period from 1965 through 1994. Through record linkage to the Swedish Cancer Register, we identified all incident cancers through 1995 in this population (693,954 person-years of observation). For each cancer type, the observed number of cases was divided by that expected in the general Swedish population to produce standardized incidence ratios (SIRs). RESULTS: Relative to the general population, the cohort had no overall cancer excess (SIR = 1.01; 95% confidence interval [CI] = 0.99 to 1.03). However, we observed elevated SIRs for prostate cancer (SIR = 1.16; 95% CI = 1.11 to 1.22) and melanoma (SIR = 1.15; 95% CI = 1.01 to 1.30) and a reduction in stomach cancer risk (SIR = 0.83; 95% CI = 0.75 to 0.92). Long-term follow-up (>or=15 years) revealed an excess of multiple myeloma (SIR = 1.86; 95% CI = 1.01 to 3.11) and a statistically nonsignificant increase in bladder cancer (SIR = 1.42; 95% CI = 0.98 to 1.99). There was no material increase in risk for bone or connective tissue cancer for either men or women in any follow-up period. CONCLUSIONS: In this, the largest study to date, hip implant patients had similar rates of most types of cancer to those in the general population. Although the excesses of melanoma, multiple myeloma, and prostate and bladder cancers may be due to chance, confounding, or detection bias and should be interpreted cautiously, they warrant further investigation because of the ever-increasing use of hip implants at younger ages.

Connective tissue disease and other rheumatic conditions following cosmetic breast implantation in Denmark.

OBJECTIVE: To examine the occurrence of connective tissue diseases (CTDs) as well as ill-defined and other rheumatic conditions among Danish women with cosmetic silicone breast implants. PATIENTS AND METHODS: A total of 2761 women with breast implants and 8807 control subjects were identified from plastic surgery private clinics and from public hospital plastic surgery departments. Women operated on at plastic surgery private clinics were identified through the files of each clinic, while women operated on at public hospitals were identified using the nationwide Danish National Registry of Patients. The control group consisted of women who underwent cosmetic surgery other than breast implantation or who only had a consultation. All women were followed up from January 1, 1977, through December 31, 1996, through the Danish National Registry of Patients for the occurrence of CTD as well as ill-defined and other rheumatic conditions. For the study period January 1, 1977, through December 31, 1994, the Danish National Registry of Patients contains information on hospitalization only, whereas data on outpatient visits are included from 1995 on, thus improving the sensitivity of the data. The implant and control groups were compared with the Danish population rates for CTD and ill-defined and other rheumatic conditions, and a direct comparison between the implant and control groups was also performed. RESULTS: When compared with rates from the general population, no excess of definite CTD was observed in the implant cohorts. For ill-defined and other rheumatic conditions, statistically significant excesses of unspecified rheumatism were observed in both the implant and control cohorts when compared with national rates. A direct comparison between the implant and control cohorts found no material differences between the groups. CONCLUSIONS: The findings of this study support previous investigations and independent review panel conclusions that an association between silicone breast implants and definite CTDs is unlikely. The observation of an excess of unspecified rheumatism among women with implants and among control women suggests that women undergoing cosmetic plastic surgery have hospitalization rates for this condition in excess of those from the general population.

Epidemiologic aspects of renal cell cancer.

Renal cell cancer accounts for about 2% of cancers worldwide. It has been increasing in incidence in North America and northern Europe, but not in other areas of the world. In the United States the rate of increase has been about 3% per year, with the highest rates now seen among blacks. Survival has improved, with the 5-year relative survival rate increasing from 30% to 40% in the 1960s to between 50% and 60% in the 1990s. A large number of epidemiologic studies, particularly case-control investigations, have searched for clues to the etiology. Cigarette smoking is a causal factor in the development of renal cell cancer. Virtually every study has identified obesity or high relative weight as another major determinant, particularly among women. High blood pressure or its medications may also play a role, although the mechanism is unknown. Occupational exposures such as asbestos, coke oven emissions, gasoline, and solvents have been related to an excess risk, but no convincing evidence exists regarding these or any other occupational factor. An inverse association between risk and intake of fruits and vegetables has been seen in a number of studies and remains one of the few consistent dietary findings. A relation with coffee, alcohol, or any other beverage has not been demonstrated for renal cell cancer and is unlikely to exist. Genetic susceptibility plays a significant role in an unknown portion of cases, likely through a number of mechanisms. Future etiologic studies should focus on the mechanism by which obesity increases risk, the role of high blood pressure and its medications, and the reasons for the remarkedly rapid increase in incidence among blacks in the United States.

Characterization and experimental use of a monospecific antiserum to factor IX.

Purified human factor IX was used to develop xenogeneic neutralizing and precipitating antibodies. The final antiserum (R2) neutralized only factor IX and was equivalent to 220 Bethesda-inhibitory units. It showed two precipitating lines, one of which disappeared after absorption with human albumin. On immunodiffusion and Laurell immunoelectrophoresis, the albumin-absorbed R2 antiserum showed one precipitin line of identity, or one rocket respectively, with normal plasma, a Red Cross factor IX preparation (rich in factors IX, II and X), the original antigen, and Hemophilia-B antigen-positive plasmas. No line or rocket developed with normal plasma absorbed with aluminum hydroxide or with antigen-negative contained only factor IX neutralizing and precipitating antibodies. Experiments with various factor IX concentrates revealed that the majority contained excess factor IX antigen compared to their coagulant activity. In addition, crossed antigen-antibody electrophoresis uncovered differences in the migration of the factor IX of Konyne preparations, when done in the presence of EDTA or calcium. This monospecific antiserum to human factor IX was subsequently used to investigate a large population of hemophilia B patients and carriers.

Genetic effects on the liability of developing pre-eclampsia and gestational hypertension.

Genetic factors are known to be important in the etiology of pre-eclampsia and possibly also gestational hypertension, but the degree of genetic influence has not been quantified. To estimate the genetic and environmental effects on the liability of developing pre-eclampsia and gestational hypertension, we cross-linked the population-based Swedish Twin Register and the Swedish Medical Birth Register. We included female twin pairs with known zygosity, both of whom gave birth in Sweden from 1973 through 1993; in all 917 monozygotic and 1,199 dizygotic twin pairs. For pre-eclampsia, the estimates of heritability and nonshared environmental effect were 0. 54 (95% confidence interval 0-0.71) and 0.46 (0.29-0.67), respectively; corresponding estimates for gestational hypertension were 0.24 (0-0.53) and 0.76 (0.47-1.00), respectively. When considering both diseases as a single entity (pregnancy-induced hypertensive diseases), the heritability estimate was 0.47 (0.13-0. 61). These results suggest that genetic factors are important in the development of pre-eclampsia as well as gestational hypertension. The heritability estimates can be of importance when planning genetic linkage studies. In efforts to identify women with elevated risk of developing pre-eclampsia during pregnancy, a question about family history of pre-eclampsia should be included.

Predictors of sex hormone levels among the elderly: a study in Greece.

This study examines the relationship between a series of epidemiologic parameters (age, height, body mass index (BMI), smoking, alcohol consumption, and coffee drinking) and serum concentrations of testosterone, estradiol, sex hormone-binding globulin (SHBG), and dehydroepiandrosterone sulfate (DHEAS). Among 52 healthy, elderly Greek men, we observed that serum levels of DHEAS decreased with increasing age [19% decline per 5-year increase in age, 95% CI, -2.1-(-33.5)], obesity [48% decline for BMI >30 kg/m2 compared to <27 kg/m2, CI, -15.7-(-68.7)], and current smoking [37% decline compared to nonsmokers, CI, -9.5-(-57.2)]. Estradiol concentrations increased with increasing BMI [77.1% increase for BMI >30 kg/m2 compared to <27 kg/m2, CI, -12.0-256.3], alcohol drinking [66% increase for > or = 7 glasses/week compared to <7 glasses/week, CI, 4.4-164.4], and coffee drinking [59% increase for > or = 14 cups/week compared to > or = 14 cups/ week, CI, -0.5-155.9], and decreased among current smokers [40% decline compared to nonsmokers, CI, -64.9-0.8]. SHBG was marginally positively associated with increasing age [13% increase per 5 years, CI, -0.5-29.6]. Testosterone was significantly related only to current smoking [27% decline compared to nonsmokers, CI, -45.4-(-3.1)]. These findings suggest that several variables appear to be associated with sex steroid levels and the influence of these findings on the occurrence of hormone-related conditions warrants further exploration.

Comparison of surrogate with self-respondents regarding medical history and prior medication use.

BACKGROUND: The self-report of medical history and medication use is a common feature of epidemiological research. METHODS: In a unique re-interview study, we evaluated the concordance of medical conditions and past medication use reported in two similar interviews 5 years apart. RESULTS: In 196 re-interviews with the subjects themselves, and in 107 with next-of-kin of subjects who died after the first interview, agreement was good or excellent (kappa > or =0.40) for 90% (9/10) of the conditions asked about in the personal medical history for both next-of-kin and self-respondents. Agreement was excellent (kappa >0.75) for two conditions, high blood pressure and hysterectomy, among self-respondents. Self- and surrogate respondents also showed similar reproducibility for prescription medications, but next-of-kin respondents tended to have poor agreement (kappa <0.40) for over-the-counter (OTC) medications such as antacids, antihistamines, and analgesics. Next-of-kin also less reliably reported a family history of cancer. When analyses were stratified by type of surrogate respondent, concordance between the two interviews was generally higher for spouses than for other surrogate respondents. CONCLUSIONS: This research demonstrates that personal medical history and prescription medication use may be as reliably reported by next-of-kin as self-respondents, but suggests that additional information may be needed to validate measures of OTC medication use and family history of cancer for next-of-kin respondents, possibly through the review of hospital records.

Laboratory prediction of the carrier state in hemophilia B: role of replication of assays.

The authors studied the effect of averaging replicated assays of Factor IX coagulation activity and Factor IX antigen on each plasma specimen in improving the ability to detect carriers of hemophilia B. The improvement resulting from this procedure is particularly marked in tests depending on the linear regression of one characteristic on another to diagnose the carrier state. The effects of averaging assays on the ratio of Factor IX coagulation activity to Factor IX antigen were also explored. The benefits of averaging replications were not greatly increased by use of more than four replications.

Effect of starvation on hypothalamic-pituitary-thyroid function in the rat.

Total starvation in the rat for 2 days did not alter the hypothalamic content of thyrotropin-releasing hormone (TRH), but did decrease both pituitary TSH content and serum TSH concentration. Five days starvation resulted in a significant decrease in serum TSH and a slightly enhanced serum TSH response to exogenous TRH, suggesting that the pituitary retains its sensitivity to TRH. Fasting for 5 days resulted in a decreased 1 and 4th, but an increased 24th thyroid 131I uptake. Other starvation-induced abnormalities of intrathyroid 131I metabolism were a consistent increase in the percent of organified 131I present as MIT and DIT and a decreased percent 131I labeled T4 AND T3. These alterations in the intrathyroid metabolism of 131I in the starved rat probably reflect both a decrease in serum TSH concentration and a decrease in urinary and fecal loss of administered 131I. The serum total and free T4 and total and free T3 concentrations were decreased following 2 and 5 days of starvation.

Occupational exposure to vinyl chloride and cancer risk: a review of the epidemiologic literature.

Occupational exposure to vinyl chloride (VC) is causally related to liver angiosarcoma, whereas there is inconsistent epidemiologic evidence for other neoplasms. Two pooled analyses of worker cohorts from 56 plants in North America and Europe provide the most comprehensive and updated data on cancer risk among workers exposed to VC. These included over 22,000 workers, with a total of 640,000 person-years of observation, followed-up for up to 50 years. Overall, a total of 1,778 cancer deaths were observed versus 1,829.46 expected, corresponding to a standardized mortality ratio (SMR) of 0.97 (95% confidence interval (CI)=0.93-1.02). Excluding 71 confirmed angiosarcomas, there were 60 deaths from liver cancers versus 44.35 expected (SMR=1.35, 95% CI=1.03-1.74). Lung and laryngeal cancer mortality were significantly lower than expected (SMR=0.88 and 0.59, respectively). The SMRs for soft tissue sarcoma, brain, lymphoid and haematopoietic system cancers were not materially different from unity. Thus, the aggregate data from over 20,000 VC workers in North America and Europe exclude any excess mortality from lung, laryngeal, soft tissue sarcoma, brain, lymphoid and haematopoietic neoplasms. There appears to be a slight excess of liver cancer other than angiosarcoma, which is difficult to interpret and is likely due to residual misclassification of angiosarcomas.