Psychiatric morbidity and the menopause; screening of general population sample.

A survey of 539 women from the general population indicated a high prevalence of minor psychiatric illness in women aged 40-55 years. There was evidence of an increase in psychiatric morbidity occurring before the menopause and lasting until about one year after menstrual periods had ended. Vasomotor symptoms increased dramatically when periods stopped and persisted up to five years after the menopause. Both these features seemed to have a clear relation to the menopause but not the same relation. The findings suggested that further investigation of the relation between perimenopausal hormonal changes and psychiatric morbidity should be directed towards premenopausal women. Environmental factors, particularly in relation to children, seemed to be associated with increased psychiatric morbidity at this time of life.     

Breast cancer risk and the interaction between adolescent body size and weight gain in later life: A case-control study

BackgroundWhile the breast cancer risk associated with increasing adult BMI in postmenopausal women can be explained by increases in concentrations of endogenous estrogens the biologic mechanisms behind the inverse association between adolescent BMI and breast cancer risk are still a subject of controversial debate.MethodsWe investigated the association of breast cancer with body size and changes in body size across life time estimated by age-specific BMI Z scores and changes in BMI Z scores from teenage years to middle age in an age-matched population-based case-control study of 2994 Australian women. Logistic regression adjusted for the matching factor age and further potential confounders was used.ResultsAdolescent body leanness in postmenopausal women and excess adult weight gain in all study participants were associated with an increased breast cancer risk with an odds ratio [95% confidence interval] of 1.29 [1.08,1.54] and 1.31 [1.09,1.59], respectively. Interaction analyses restricted to postmenopausal women revealed an increased risk of breast cancer in those who were lean during adolescence and gained excess weight during adulthood (odds ratio [95% confidence interval]: 1.52 [1.19,1.95]) but not in women who were lean during adolescence and did not gain excess weight during adulthood (1.20 [0.97,1.48]) and not in women who were not lean during adolescence and but gained excess weight during adulthood (1.10 [0.95,1.27]) compared to postmenopausal women who were neither lean during adolescence nor gained excess weight.ConclusionIn postmenopausal women adolescent leanness was only associated with increased breast cancer risk when excess weight was gained during adulthood.     

Gender differences in musculotendinous stiffness and range of motion after an acute bout of stretching

The purpose of the present study was to examine musculotendinous stiffness (MTS) and ankle joint range of motion (ROM) in men and women after an acute bout of passive stretching. Thirteen men (mean ± SD age = 21 ± 2 years; body mass = 79 ± 15 kg; and height = 177 ± 7 cm) and 19 women (21 ± 3 years; 61 ± 9 kg; 165 ± 8 cm) completed stretch tolerance tests to determine MTS and ROM before and after a stretching protocol that consisted of 9 repetitions of passive, constant-torque stretching. The women were all tested during menses. Each repetition was held for 135 seconds. The results indicated that ROM increased after the stretching for the women (means ± SD pre to post: 109.39° ± 10.16° to 116.63° ± 9.63°; p ≤ 0.05) but not for the men (111.79° ± 6.84° to 113.93° ± 8.15°; p > 0.05). There were no stretching-induced changes in MTS (women's pre to postchange in MTS: -0.35 ± 0.38; men's MTS: +0.17 ± 0.40; p > 0.05), but MTS was higher for the men than for the women (MTS: 1.34 ± 0.41 vs. 0.97 ± 0.38; p ≤ 0.05). electromyographic amplitude for the soleus and medial gastrocnemius during the stretching tests was unchanged from pre to poststretching (p > 0.05); however, it increased with joint angle during the passive movements (p ≤ 0.05). Passively stretching the calf muscles increased stretch tolerance in women but not in men. But the stretching may not have affected the viscoelastic properties of the muscles. Practitioners may want to consider the possible gender differences in passive stretching responses and that increases in ROM may not always reflect decreases in MTS.     

Effect of age and Gender on Fasting and Food-Stimulated Levels of Calcitonin,Parathyroid, and Gastrin Hormones in Healthy Adults

Objective: To investigate the effect of age and gender on basal and food-stimulated serum calcitonin (CT), parathyroid hormone (PTH), and gastrin levels among healthy adults.Methods: Ninety-six healthy adults (76 men and 20 women) aged between 21 and 43 years were recruited. Serum CT, PTH, and gastrin levels were measured after a 9-hour overnight fast, and 1 and 3 hours postprandially.Results: PTH levels decreased early and increased late after feeding. This change was significant in men but not in women. CT levels increased in response to food intake in men but not in women. Gastrin levels were significantly increased after feeding in both men and women. Mean basal and food stimulated CT, PTH, and gastrin levels did not significantly differ between genders. Fasting and post-prandial PTH levels were higher while gastrin levels were lower in older subjects (>30 years old) compared to younger subjects (≤30 years old). Fasting and postprandial CT levels were not significantly different between age groups.Conclusion: Age had a significant effect on fasting and food-stimulated PTH and gastrin hormone levels. The effect of age on PTH levels was independent of baseline vitamin D levels. Men showed significant changes in CT and PTH levels in response to feeding compared to women, although the mean hormone levels were not significantly different between men and women.Abbreviations: CT = calcitonin; MTC = medullary thyroid carcinoma; PTH = parathyroid hormone; SD = standard deviation     

A prospective study of overweight, physical activity, and depressive symptoms in young women

This study examined the prospective associations of BMI, physical activity (PA), changes in BMI, and changes in PA, with depressive symptoms. Self-reported data on height, weight, PA, selected sociodemographic and health variables and depressive symptoms (CESD-10) were provided in 2000 and 2003 by 6,677 young adult women (22-27 years in 2000) participating in the Australian Longitudinal Study on Women's Health (ALSWH). Results of logistic regression analyses showed that the odds of developing depressive symptoms at follow-up (2003) were higher in women who were overweight or obese in 2000 than in healthy weight women, and lower in women who were active in 2000 than in sedentary women. Changes in BMI were significantly associated with increased odds of depressive symptoms at follow-up. Sedentary women who increased their activity had lower odds of depressive symptoms at follow-up than those who remained sedentary. Increases in activity among initially sedentary young women were protective against depressive symptoms even after adjusting for BMI changes. These findings indicate that overweight and obese young women are at risk of developing depressive symptoms. PA appears to be protective against the development of depressive symptoms, but does not attenuate the depressive symptoms associated with weight gain. However, among initially sedentary young women, even small increases in PA over time may reduce the odds of depressive symptoms, regardless of weight status.     

Effects of aging on bone mineral content and bone biomarkers in female cynomolgus monkeys.

Age-related changes in bone mineral content and bone biomarkers were assessed over the complete lifespan of female cynomolgus monkeys. The bone mass of the lumbar spine increased linearly from birth to about 2.5 years of age, and this increase gradually slowed thereafter until a peak bone mass was achieved at 9 years of age. The bone mass stabilized after 9 years of age, showing no sign of further reduction with age. In contrast with the significant increase in bone mass before 2.5 years of age, significant decreases occurred in the serum concentrations of the following bone formation markers: intact osteocalcin, bone-specific alkaline phosphatase and amino-terminal propeptide of type I procollagen, but the serum concentration of carboxy-terminal propeptide of type I procollagen did not change significantly throughout the entire lifespan. Concerning the bone resorption markers, the levels of tartrate-resistant acid phosphatase fluctuated throughout the entire lifespan. The skeleton of an aging female monkey undergoes changes similar to those observed in senescent humans, but did not undergo the menopausal changes seen in women. The use of female cynomolgus monkeys to model human skeletal interventions should therefore be undertaken with consideration of the similarities and differences between cynomolgus monkeys and humans.     

My father's life.

Medicine has many unsung heroes, and among them are physicians who spend their careers providing medical care in remote areas. In this article, Ronald Porth remembers the life of his father, Dr. Frank Porth, who for more than 30 years provided medical care on native reserves and in rural parts of the Prairies.     

Sex-specific HDL cholesterol changes with weight loss and their association with anthropometric variables: the LIFE study

Decrease in the level of high-density lipoprotein cholesterol (HDLC) has been observed in women who start dieting, but not in men. Patterns of HDLC change during intentional weight loss through 30-months of follow-up, and their association with changes in anthropometric measurements were examined in obese women (N = 112) and men (N = 100). Missing HDLC values at 6-, 12-, 18-, and 30-month follow-up (N = 16, 34, 55, and 50, respectively) due to dropout were imputed by multiple imputation. Mean ages and BMIs of subjects at baseline were 47.2 years and 34.8 kg/m(2) for women, and 50.4 years and 35.0 kg/m(2) for men. On average, participants lost weight steadily for 12 months, followed by slow regain. During the first 6 months, HDLC decreased significantly in women (-4.1 mg/dl, P = 0.0007), but not in men. Significant HDLC increases were observed in both men and women from 6- to 12-month follow-up. HDLC changes in women were positively associated with changes in hip circumference from baseline to 12-month independent of changes in triglycerides (TG), glucose, and insulin. Rapid decrease of predominantly subcutaneous fat in the femoral and gluteal area might be associated with HDLC decrease in women during initial weight loss.     

Gender Difference in Accumulation of Calcium and Phosphorus in the Left Coronary Arteries of Thais

To examine whether there were gender differences in compositional changes of the coronary artery with aging, the authors investigated the gender difference in age-related changes of elements in the left coronary arteries of Thais by direct chemical analysis. After ordinary dissections by students at Chiang Mai University were finished, the left coronary arteries were resected from Thai subjects. The Thai subjects consisted of 69 men and 34 women. The ages of the male subjects ranged from 25 to 87?years (average age?=?62.6?±?11.4?years) and of the female subjects from 24 to 86?years (average age?=?59.4?±?14.6?years). After incinerating the arteries with nitric acid and perchloric acid, the element content was determined by inductively coupled plasma-atomic emission spectrometry. The Ca and P contents tended to increase in the left coronary arteries of men with age, but the increases were not statistically significant. In the left coronary arteries of women, the Ca and P contents increased significantly and progressively with aging. In addition, the Na content increased significantly in the left coronary arteries of both men and women with aging. The differences in the average contents of Ca and P by age group were observed between the left coronary arteries of men and women. With Student's t test, significant gender differences in the average contents of Ca and P were found in both the 40s and the 70s. The Ca and P contents of the left coronary arteries in the 40s were significantly higher in men than in women. In contrast, the Ca and P contents in the 70s were significantly higher in women than in men. These results indicated that the accumulation of Ca and P in the left coronary arteries of Thais occurred at least 10?years earlier in men than in women, but a higher accumulation of Ca and P in old age occurred in the left coronary arteries of women compared with those of men. The present study revealed that there were significant gender differences in the left coronary arteries with regard to the accumulation of Ca and P with aging. It is reasonable to presume that taking clinical findings into consideration, the gender differences in the left coronary arteries may result from hormonal and/or genetic factors rather than lifestyle factors.     

Population based study of rates of multiple pregnancies in Denmark, 1980-94.

OBJECTIVE: To study trends in multiple pregnancies not explained by changes in maternal age and parity patterns. DESIGN: Trends in population based figures for multiple pregnancies in Denmark studied from complete national records on parity history and vital status. POPULATION: 497,979 Danish women and 803,019 pregnancies, 1980-94. MAIN OUTCOME MEASURES: National rates of multiple pregnancies, infant mortality, and stillbirths controlled for maternal age and parity. Special emphasis on primiparous women > or = 30 years of age, who are most likely to undergo fertility treatment. RESULTS: The national incidence of multiple pregnancies increased 1.7-fold during 1980-94, the increase primarily in 1989-94 and almost exclusively in primiparous women aged > or = 30 years, for whom the adjusted population based twinning rate increased 2.7-fold and the triplet rate 9.1-fold. During 1989-94, the adjusted yearly increase in multiple pregnancies for these women was 19% (95% confidence interval 16% to 21%) and in dizygotic twin pregnancies 25% (21% to 28%). The proportion of multiple births among infant deaths in primiparous women > or = 30 years increased from 11.5% to 26.9% during the study period. The total infant mortality, however, did not increase for these women because of a simultaneous significant decrease in infant mortality among singletons. CONCLUSIONS: A relatively small group of women has drastically changed the overall national rates of multiple pregnancies. The introduction of new treatments to enhance fertility has probably caused these changes and has also affected the otherwise decreasing trend in infant mortality. Consequently, the resources, both economical and otherwise, associated with these treatments go well beyond those invested in specific fertility enhancing treatments.     

Effect of canopy size and shape on the tuber yield of sixteen potato genotypes

An experiment was conducted to evaluate the utility of visual assessment of canopy characteristics in the selection of high-yielding clones for the southern Canadian Prairies. Over a 3-yr period the yield development characteristics of 16 genotypes, selected to represent a range of canopy types, both in size and shape, were studied by destructive sampling at five stages during the growing season. While the response over harvest dates was not consistent for the canopy size or shape groups for most yield variables, it was demonstrated that under the short season growing conditions in southern Alberta, canopies intermediate in size and degree of upright growth habit appear to be most efficient in terms of maximising tuber bulking rates. It was concluded that for the southern Canadian Prairies, selection of genotypes with these types of canopy structure is consistent with the objective of developing early-maturing cvs with high tuber yield.     

Oxytocinergic activity is linked to lower blood pressure and vascular resistance during stress in postmenopausal women on estrogen replacement

Estrogen administration results in increased release of the oxytocin (OT) prohormone reflected by increases in oxytocin intermediate peptide (OT Int) in both animal models and humans, and sequential treatment of ovariectomized rats with estrogen/progesterone then progesterone withdrawal leads to increased hypothalamic OT mRNA. Blood pressure (BP) reductions have been related to increased exogenous and endogenous OT in rats and to higher endogenous OT activity in premenopausal women, but not previously in postmenopausal women. Thus, we used plasma obtained at rest and during a speech stressor from 54 postmenopausal women who participated in a 6-month randomized trial of oral conjugated estrogens vs. placebo to examine effects of estrogen replacement therapy (ERT) on plasma OT and OT Int levels and their relationships to changes in BP during the trial. ERT alone and with progesterone (but not placebo) led to significant increases in plasma levels of OT Int, but no change in plasma OT levels. Women showing greater increases in OT Int during treatment showed greater decreases in BP and total vascular resistance during a series of behavioral stressors compared to women with moderate or no increases in OT Int, even after controlling for effects related to treatment condition or to changes in plasma estradiol. The findings suggest that enhanced oxytocinergic activity may contribute to BP decreases associated with ERT in more responsive postmenopausal women.     

Effects of estrogen replacement therapy on abdominal fat compartments as related to glucose and lipid metabolism in early postmenopausal women.

The effects of estrogen replacement therapy on lipid and glucose metabolism as related to abdominal fat distribution were investigated in fifty-one healthy postmenopausal women aged 52-53 years. They were randomized to treatment with either estradiol 2 mg or placebo daily for three months in a double-blind design. Forty-six women continued with estradiol for another nine months in an open design with the addition of medroxyprogesterone for ten days every three months. Intra-abdominal and subcutaneous abdominal fat, and intrapelvic and subcutaneous pelvic fat was estimated by computed tomography before and after one year of estrogen treatment. Euglycemic hyperinsulinemic clamp, oral glucose tolerance test and analyses of blood lipids were performed after 3 and 12 months of treatment. Estrogen replacement therapy decreased body fat mass as well as intra-abdominal and intrapelvic fat, but not the subcutaneous fat compartments. LDL cholesterol decreased and HDL cholesterol increased, whereas triglycerides were not changed by one year of estrogen treatment. Insulin sensitivity and glucose tolerance were not affected by estrogen treatment. In postmenopausal women estrogen treatment for one year decreased intra-abdominal and intrapelvic fat compartments, but this was not related to changes in plasma lipid levels. Insulin sensitivity and plasma triglycerides were not affected by estrogen treatment.     

The effect of weight loss on serum concentrations of FAS and tumour necrosis factor alpha in obese women

INTRODUCTION: Apoptosis can influence both adipose tissue mass and its distribution. The suprafamily of tumour necrosis factor (TNF) receptors stimulate apoptosis. The aim of the study was to assess serum concentrations of tumour necrosis factor alpha (TNF-alpha), TNF soluble receptors (sTNFRs) and FAS in obese subjects and to examine the changes in these parameters after weight loss. MATERIAL AND METHODS: The study group consisted of 23 obese women without additional disease aged 36.6 +/- 10.9 years. These were examined before and after three-month weight reduction treatment consisting of a diet of 1000 kcal/day and physical exercise. The control group comprised 17 lean healthy women aged 40.3 +/- 5.5 years. Blood samples were taken in the morning after an overnight fast. Serum concentrations of TNF-alpha, sTNFRs and FAS were measured by enzyme linked immunosorbent assay (ELISA). Serum concentrations of insulin were measured by RIA. Serum concentrations of glucose, total cholesterol, HDL cholesterol and triglycerides were measured by an enzymatic procedure. RESULTS: The mean weight loss over the three-month treatment was 11.4 +/- 3.1 kg. Following weight loss, serum TNF-alpha concentrations decreased significantly (7.3 +/- 3.0 vs. 5.4 +/- 1.6 pg/ml; p < 0.005) and concentrations of sTNFRs increased significantly (1222.6 +/- 211.8 vs. 1325.6 +/- 261.6 pg/ml; p < 0.05 and 1881.5 +/- 337.2 vs. 2057.4 +/- 358.7 pg/ml; p < 0.05 respectively). However, no changes in serum concentrations of FAS were observed after weight loss. CONCLUSION: We observed increased serum concentrations of TNF-alpha but not of FAS in obese women. The concentrations of TNF decreased and those of sTNFRs increased after weight loss. However, the weight reduction therapy did not change serum concentrations of FAS.     

The prevalence of hypertension among elderly Navajos: A test of the acculturative stress hypothesis

This is a study of the prevalence of hypertension among a sample of Navajo Indians 65 years of age and above. It is not clear whether prevalence has increased over the past generation in this age group. When men and women are compared, conventional measures of "acculturation" are related to hypertension among women but not among men. The differences between men and women seem most probably related to differences in the situation of men and women within both Navajo and Anglo-American society. Several alternative explanations are discussed as well.     

Contribution from geriatric medicine within acute medical wards.

In 1977 a scheme of attachment to acute medical wards of consultants in geriatric medicine and associated junior medical staff was instituted in a large Edinburgh teaching hospital. The effect on admissions of patients aged 65 and over was examined for comparable periods before and during this arrangement. Mean and median stays were reduced for both sexes but more noticeably for women. The mean stay for all women aged over 65 was reduced from 25 to 16 days and for women aged over 85 from 50 to 19 days. The proportion staying under two weeks was significantly increased in both sexes, and the proportion discharged home also increased, correspondingly fewer patients being transferred to convalescent wards. These changes were not accompanied by increased transfers to the geriatric department, and probably the skills and extra resources available to the geriatric service were the factors mainly responsible for the changes in performance.     

Reproductive and external hormonal factors and the risk of renal cell cancer in the Netherlands Cohort Study

BackgroundSeveral reproductive and hormonal factors, like age at menarche, parity, age at menopause, use of oral contraceptives and postmenopausal treatment, have been associated with the risk of renal cell cancer (RCC) in women, but results have not always been consistent. We therefore investigated the association between these factors and the risk of RCC in postmenopausal women participating in the Netherlands Cohort Study on Diet and Cancer.MethodsInformation on reproductive history, exogenous hormone use and gynecological surgery was obtained through a self-administered questionnaire at baseline in 1986. After 20.3 years of follow-up, 204 cases and 2280 subcohort members were available for case-cohort analysis. Multivariable hazard ratios (HR) were calculated using Cox Proportional Hazard analysis.ResultsWomen who reported a hysterectomy had an increased RCC risk compared to women who did not (HR, 1.42, 95%CI, 1.01–2.00). Women with a natural age at menopause between 45 and 49 years compared to 50–54 years had an increased RCC risk (HR, 1.61; 95%CI, 1.10–2.35). RCC risk was slightly and not statistically significant increased among parous women with three or more children and age at first birth before 25 years compared to nulliparous women (HR, 1.36; 95% confidence interval (CI), 0.84–2.20). No associations were observed with RCC risk for age at menarche, use of oral contraceptives and use of hormonal replacement therapy.ConclusionHysterectomy and age at natural menopause were associated with an increased RCC risk. Other hormonal and reproductive factors and RCC risk were not increased. Further studies are required to establish the mechanism(s) that explain the observed association.     

Participation in clinical trials among women living with HIV in Canada

BACKGROUND: To describe participation in clinical trials among HIV-positive women enrolled since 1993 in the Canadian Women''s HIV Study, a prospective open cohort study. METHODS: All HIV-positive women being followed at hospital-based or community-based clinics at 28 sites in 11 Canadian cities were eligible to participate in the Canadian Women''s HIV Study. Baseline and follow-up information was collected for 413 women every 6 months by study nurses using standardized questionnaires. Data included sociodemographic variables, HIV exposure group, CD4 count, disease classification, use of antiretroviral therapies and participation in clinical trials. RESULTS: At study intake 15.0% (62/413) of the women had participated in a clinical trial; an additional 8.5% (35/413) participated during a median follow-up of 18 months. Multivariate analysis revealed that the following factors were independently associated with participation in a clinical trial: white race (adjusted odds ratio [OR] 3.38, p = 0.001), current use of antiretroviral therapy (adjusted OR 2.01, p = 0.008), completion of secondary school (adjusted OR 1.97, p = 0.024) and residence in the Prairies or Atlantic provinces (adjusted OR 1.98, p = 0.043). INTERPRETATION: Although the overall clinical trial participation rate of 23.5% was relatively high among HIV-positive women, injection drug users were underrepresented in this study population, and non-white women, women who did not complete high school and women not receiving antiretroviral therapy were less likely than white women, women of higher education and women receiving antiretroviral therapy to participate in clinical trials in Canada. Because of the importance of trial participants being representative of the population for which therapeutic agents are intended, HIV clinical trials must recruit women with lower literacy levels, non-white women, women not receiving antiretroviral therapy and women who are injection drug users to ensure generalizability of research findings. Further study is needed to assess factors that act as barriers and motivators to women''s participation in HIV clinical trials.     

Smoking Kills,Obesity Disables: A Multistate Approach of the US Health and Retirement Survey

Increasing BMI causes concerns about the consequences for health care. Decreasing cardiovascular mortality has lowered obesity‐related mortality, extending duration of disability. We hypothesized increased duration of disability among overweight and obese individuals. We estimated age‐, risk‐, and state‐dependent probabilities of activities of daily living (ADL) disability and death and calculated multistate life tables, resulting in the comprehensive measure of life years with and without ADL disability. We used prospective data of 16,176 white adults of the Health and Retirement Survey (HRS). Exposures were self‐reported BMI and for comparison smoking status and levels of education. Outcomes were years to live with and without ADL disability at age 55. The reference categories were high normal weight (BMI: 23–24.9), nonsmoking and high education. Mild obesity (BMI: 30–34.9) did not change total life expectancy (LE) but exchanged disabled for disability‐free years. Mild obesity decreased disability‐free LE with 2.7 (95% confidence limits 1.2; 3.2) year but increased LE with disability with 2.0 (0.6; 3.4) years among men. Among women, BMI of 30 to 34.9 decreased disability‐free LE with 3.6 (2.1; 5.1) year but increased LE with disability with 3.2 (1.6;4.8) years. Overweight (BMI: 25–29.9) increases LE with disability for women only, by 2.1 (0.8; 3.3) years). Smoking compressed disability by high mortality. Smoking decreased LE with 7.2 years, and LE with disability with 1.3 (0.5; 2.5) years (men) and 1.4 (0.3; 2.6) years (women). A lower education decreased disability‐free life, but not duration of ADL disability. In the aging baby boom, higher BMI will further increase care dependence.     

Associations between obesity and changes in adult BMI over time and colon cancer risk

Obesity has been associated with increased colon cancer risk in epidemiological studies; however, the specific time periods during which obesity may be most relevant as well as how changes in adult body size over time affect colon cancer risk have not been well explored. We evaluated potential associations between BMI in each age decade(20s, 30s, 40s, 50s, and 2 years before study recruitment ("recruitment period")) and in BMI changes over timeand colon cancer risk in a population-based case-control study comprising 438 cases and 491 controls. We found that obese (BMI>or=30.0 kg/m2) compared to normal (BMI>or=18.5 to <25.0 kg/m2) body size at the recruitment period was associated with increased colon cancer risk (odds ratio (OR)=1.54; 95% confidence interval (CI)=1.03-2.31; P=0.03). No associations were observed for obese body size in the other age decades. An increased risk was found for changes in BMI between the 30s decade and the recruitment period of 5-10 kg/m2 (OR=1.54; 95%CI=1.02-2.34; P=0.04) and >10 kg/m2 (OR=2.40; 95% CI=1.23-4.66; P=0.01) (P trend=0.01). Stratification by gender revealed that BMI changes>10 kg/m2 increased risk in women but not men. Similar results were found for BMI changes between the 20s decade and the recruitment period but effect sizes were smaller. Our results provide additional support to obesity's role in colon cancer and suggest large body size increases exceeding 10 kg/m2 may potentially be more important after age 30, particularly among women; however, prospective studies with sex hormone, growth factor, and pro-inflammatory biomarkers are needed to provide insights to the underlying biological mechanism(s).