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1.  Age-specific effects of hormone therapy use on overall mortality and ischemic heart disease mortality among women in the California Teachers Study 
Menopause (New York, N.y.)  2011;18(3):253-261.
Objective
Although the Women’s Health Initiative trial (WHI) suggested that menopausal hormone therapy (HT) does not reduce coronary heart disease mortality overall, subsequent results have suggested that there may be a benefit in younger women. The California Teachers Cohort Study (CTS) questionnaire and mortality data was used to examine whether age modified the association between HT and the relative risk of overall mortality and ischemic heart disease (IHD) deaths.
Methods
Participants from the CTS were 71,237 postmenopausal women (mean age = 63, range 36 to 94 years) followed prospectively for mortality and other outcomes from 1995–1996 through 2004.
Results
Age at baseline was a much more important modifier of HT effects than age at start of therapy. Risks for all-cause mortality (n=8,399) were lower for younger current HT users at baseline than for never users (for women ≤60 years: HR=0.54, 95% CI=0.46–0.62). These risk reductions greatly diminished, in a roughly linear fashion, with increasing baseline age (for women 85–94 years HR=0.94, 95% CI=0.81–1.10 for all-cause mortality). Similar results were seen for IHD deaths (n=1,464). No additional significant modifying effects of age at first use, duration of use, or formulation were apparent.
Conclusions
These results provide evidence that reduced risks of mortality associated with HT use are observed among younger users but not for older postmenopausal women even those starting therapy close to their time of menopause.
doi:10.1097/gme.0b013e3181f0839a
PMCID: PMC3253313  PMID: 20881652
Overall mortality; heart disease; menopausal hormone therapy; risk; survival; age
2.  Alcohol Consumption Over Time and Risk of Lymphoid Malignancies in the California Teachers Study Cohort 
American Journal of Epidemiology  2010;172(12):1373-1383.
Several previous studies found inverse associations between alcohol consumption and risk of non-Hodgkin lymphoma (NHL) and multiple myeloma. However, most studies were retrospective, and few distinguished former drinkers or infrequent drinkers from consistent nondrinkers. Therefore, the authors investigated whether history of alcohol drinking affected risks of NHL and multiple myeloma among 102,721 eligible women in the California Teachers Study, a prospective cohort study in which 496 women were diagnosed with B-cell NHL and 101 were diagnosed with multiple myeloma between 1995–1996 and December 31, 2007. Incidence rate ratios and 95% confidence intervals were estimated using Cox proportional hazards regression. Risk of all types of B-cell NHL combined or multiple myeloma was not associated with self-reported past consumption of alcohol, beer, wine, or liquor at ages 18–22 years, at ages 30–35 years, or during the year before baseline. NHL subtypes were inconsistently associated with alcohol intake. However, women who were former alcohol drinkers at baseline were at elevated risk of overall B-cell NHL (rate ratio = 1.46, 95% confidence interval: 1.08, 1.97) and follicular lymphoma (rate ratio = 1.81, 95% confidence interval: 1.00, 3.28). The higher risk among former drinkers emphasizes the importance of classifying both current and past alcohol consumption and suggests that factors related to quitting drinking, rather than alcohol itself, may increase B-cell NHL risk.
doi:10.1093/aje/kwq309
PMCID: PMC3105275  PMID: 20952595
alcohol drinking; cohort studies; lymphoma, non-Hodgkin; multiple myeloma
3.  Body size and the risk of ovarian cancer by hormone therapy use in the California Teachers Study cohort 
Cancer causes & control : CCC  2010;21(12):2241-2248.
Objective
To investigate whether obesity and hormone therapy (HT) are associated with ovarian cancer risk among women in the California Teachers Study cohort.
Methods
Of 56,091 women age ≥45 years, 277 developed epithelial ovarian cancer between 1995 and 2007. Multivariate Cox regression was performed.
Results
Among women who never used HT, greater adult weight gain, waist circumference and waist-to-height ratio, but not adult BMI, increased risk of ovarian cancer. Compared to women who never used HT and had a stable adult weight, risk of ovarian cancer was increased in women who gained ≥40 lb (relative risk (RR) 1.8, 95% confidence interval (CI): 1.0–3.0) or used HT for >5 years (RR 2.3 95% CI: 1.3–4.1). Having both exposures (RR 1.9, 95% CI: 0.99–3.5), however, did not increase risk more than having either alone. Results were similar for waist circumference and weight-to-height ratio; however, differences across HT groups were not statistically significant.
Conclusions
This study suggests that abdominal adiposity and weight gain, but not overall obesity, increase ovarian cancer risk and that there may be a threshold level beyond which additional hormones, whether exogenous or endogenous, do not result in additional elevation in risk. However, large pooled analyses are needed to confirm these findings.
doi:10.1007/s10552-010-9647-x
PMCID: PMC3120052  PMID: 20924664
Ovarian cancer; Obesity; Abdominal adiposity; Hormone therapy
4.  Body size and the risk of endometrial cancer by hormone therapy use in postmenopausal women in the California Teachers Study cohort 
Cancer causes & control : CCC  2010;21(9):1407-1416.
Objective
To investigate whether hormone therapy (HT) and obesity are associated with endometrial cancer risk among postmenopausal women in the California Teachers Study cohort.
Methods
Of 28,418 postmenopausal women, 395 developed type 1 endometrial cancer between 1995 and 2006. Multivariate Cox regression was performed to estimate relative risks (RR), stratified by HT use (never used, ever estrogen-alone (ET), or exclusively estrogen-plus-progestin (EPT)).
Results
Among women who never used HT, overall and abdominal adiposity were associated with increased risk; when evaluated simultaneously, abdominal adiposity was more strongly associated (RR 2.2, 95% confidence interval (CI): 1.1–4.5 for waist ≥35 vs. <35 inches). Among women who ever used ET, risk was increased in women with BMI ≥25 kg/m2 (RR 1.6, 95% CI: 1.1–2.3 vs. <25 kg/m2). Neither overall nor abdominal obesity was associated with risk in women who exclusively used EPT (P-interaction<0.001 for BMI by HT use).
Conclusions
Among women who never used HT, risk was strongly positively related to obesity and may have been influenced more by abdominal than overall adiposity; however, due to small numbers, this latter finding requires replication. Among women who ever used ET, being overweight at baseline predicted higher risk, whereas use of EPT mitigated any effect of obesity.
doi:10.1007/s10552-010-9568-8
PMCID: PMC2925506  PMID: 20431936
endometrial cancer; obesity; abdominal adiposity; hormone therapy
5.  Body Size, Recreational Physical Activity, and B-Cell Non-Hodgkin Lymphoma Risk Among Women in the California Teachers Study 
American Journal of Epidemiology  2009;170(10):1231-1240.
Nutritional status and physical activity are known to alter immune function, which may be relevant to lymphomagenesis. The authors examined body size measurements and recreational physical activity in relation to risk of B-cell non-Hodgkin lymphoma (NHL) in the prospective California Teachers Study. Between 1995 and 2007, 574 women were diagnosed with incident B-cell NHL among 121,216 eligible women aged 22–84 years at cohort entry. Multivariable-adjusted relative risks and 95% confidence intervals were estimated by fitting Cox proportional hazards models for all B-cell NHL combined and for the 3 most common subtypes: diffuse large B-cell lymphoma, follicular lymphoma, and B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma. Height was positively associated with risk of all B-cell NHLs (for >1.70 vs. 1.61–1.65 m, relative risk = 1.50, 95% confidence interval: 1.16, 1.96) and chronic lymphocytic leukemia/small lymphocytic lymphoma (relative risk = 1.93, 95% confidence interval: 1.09, 3.41). Weight and body mass index at age 18 years were positive predictors of B-cell NHL risk overall. These findings indicate that greater height, which may reflect genetics, early life immune function, infectious exposures, nutrition, or growth hormone levels, may play a role in NHL etiology. Adiposity at age 18 years may be more relevant to NHL etiology than that in later life.
doi:10.1093/aje/kwp268
PMCID: PMC2781760  PMID: 19822569
body mass index; body size; cohort studies; exercise; hip; lymphoma, non-Hodgkin; waist-hip ratio
6.  Long-term and recent recreational physical activity and survival after breast cancer: the California Teachers Study 
Introduction
Long-term physical activity is associated with lower breast cancer risk. Little information exists on its association with subsequent survival.
Methods
California Teachers Study cohort members provided information in 1995–1996 on long-term (high school through age 54 years) and recent (past 3 years) participation in moderate and strenuous recreational physical activities. The 3,539 women diagnosed with invasive breast cancer after cohort entry and through December 31, 2004, were followed through December 31, 2005. Of these, 460 women died, 221 from breast cancer. Moderate and strenuous physical activities were combined into low (≤0.50 hr/wk/yr of any activity), intermediate (0.51–3.0 hr/wk/yr of moderate or strenuous activity but no activity >3.0 hr/wk/yr) or high activity (>3.0 hr/wk/yr of either activity type). Multivariable relative risks (RR) and 95% confidence intervals (CI) for mortality were estimated using Cox proportional hazards methods, adjusting for race/ethnicity, estrogen receptor status, disease stage, and baseline information on comorbidities, body mass index, and caloric intake.
Results
Women with high or intermediate levels of long-term physical activity had lower risk of breast cancer death (RR=0.53, 95% CI=0.35–0.80; and RR=0.65, 95% CI=0.45–0.93, respectively) than women with low activity levels. These associations were consistent across estrogen receptor status and disease stage, but confined to overweight women. Deaths due to causes other than breast cancer were related only to recent activity.
Conclusions
Consistent long-term participation in physical activity before breast cancer diagnosis may lower risk of breast cancer death, providing further justification for public health strategies to increase physical activity throughout the lifespan.
doi:10.1158/1055-9965.EPI-09-0538
PMCID: PMC2783945  PMID: 19843680
7.  Incomplete pregnancy is not associated with breast cancer risk: the California Teachers Study 
Contraception  2008;77(6):391-396.
Background
Early studies of incomplete pregnancy and development of breast cancer suggested that induced abortion might increase risk. Several large prospective studies, which eliminate recall bias, did not detect associations but this relationship continues to be debated.
Study design
To further inform this important question, we examined invasive breast cancer as it relates to incomplete pregnancy, including total number of induced abortions, age at first induced abortion and total number of miscarriages among women participating in the ongoing California Teachers Study (CTS) cohort. Incomplete pregnancy was self-reported on the CTS baseline questionnaire in 1995–96. Incident breast cancers were ascertained in 3,324 women through 2004 via linkage with the California Cancer Registry.
Results
Using Cox multivariable regression, we found no statistically significant association between any measure of incomplete pregnancy and breast cancer risk among nulliparous or parous women.
Conclusion
These results provide strong evidence that there is no relationship between incomplete pregnancy and breast cancer risk.
doi:10.1016/j.contraception.2008.02.004
PMCID: PMC2473863  PMID: 18477486
breast cancer; incomplete pregnancy

Results 1-7 (7)