Faculty Bibliography

BACKGROUND: Work-related musculoskeletal disorders (WMSDs) have a significant impact on physical therapists, but few studies have addressed the issue. Research is needed to determine the scope of the problem and the effects of specific risk factors. OBJECTIVES: The objectives of this study were: (1) to determine the 1-year incidence rate of WMSDs in physical therapists and (2) to determine the effects of specific risk factors. DESIGN: This was a prospective cohort study with 1-year follow-up. METHODS: Subjects were randomly selected American Physical Therapy Association members (N=882). Exposure assessment included demographic data, physical risk factors, job strain, and specific physical therapy tasks. The primary outcome was WMSDs, with a severity rating of at least 4/10 and present at least once a month or lasting longer than a week. RESULTS: The response rate to the baseline questionnaire was 67%. Ninety-three percent of the subjects who responded to the baseline questionnaire responded to the follow-up questionnaire. The 1-year incidence rate of WMSDs was 20.7%. Factors that increased the risk for WMSDs included patient transfers, patient repositioning, bent or twisted postures, joint mobilization, soft tissue work, and job strain. LIMITATIONS: The primary limitation of this study was the number of therapists who had a change in their job situation during the follow-up year. CONCLUSIONS: Work-related musculoskeletal disorders are prevalent in physical therapists. Physical therapy exposures, patient handling, and manual therapy, in particular, increase the risk for WMSDs

The vitamin D receptor (VDR) is a critical mediator of the cellular effects of vitamin D. The associations between four common VDR polymorphisms (BSMI, APAI, TAQI, and FOKI) and risk of epithelial ovarian cancer (EOC) were assessed in a case-control study nested within two prospective cohorts. One hundred seventy incident cases of EOC and 323 individually matched controls were genotyped. Overall, no associations were observed in genotype analyses. Haplotypes combining three SNPs in high linkage disequilibrium (BSMI, APAI, and TAQI) were also not associated with risk. These observations do not support a role for BSMI, APAI, TAQI, and FOKI polymorphisms in epithelial ovarian cancer in a predominantly Caucasian population

PURPOSE: The aim of the study is to determine the reliability during a 2-year period of several newly developed iron-related assays to assess their potential for use in prospective epidemiologic studies. METHODS: We assessed the temporal reliability of several iron-related assays by using three serum samples collected at yearly intervals from 50 postmenopausal participants in a large prospective study. RESULTS: We observed high reliability coefficients for ferritin (0.78; 95% confidence interval [CI], 0.67-0.86), soluble transferrin receptor (sTfR; 0.79; 95% CI, 0.69-0.87), sTfR/ferritin ratio (0.74; 95% CI, 0.62-0.83), and hepcidin (0.89; 95% CI, 0.84-0.94). In a subset of 30 women, lower reliability was observed for serum iron (0.50; 95% CI, 0.29-0.70), unsaturated iron-binding capacity (0.55; 95% CI, 0.34-0.73), total iron-binding capacity (0.60; 95% CI, 0.40-0.76), and serum transferrin saturation rate (0.44; 95% CI, 0.22-0.65). The reliability of anti-5-hydroxymethyl-2'-deoxyuridine autoantibody titers, a biomarker of oxidized DNA damage, one of the mechanisms by which iron is thought to impact disease risk, was very high (0.97, 95% CI, 0.5-0.99). CONCLUSIONS: Our results show that some newly developed iron-related assays could be useful tools to assess iron-disease associations in prospective cohorts that collect a single blood sample

It has been suggested that phytoestrogens protect against hormone-dependent cancers. Lignans are the main class of phytoestrogens in Western diets. We conducted a prospective study of endometrial cancer and circulating levels of the main human lignan, enterolactone. The design was a case-control study nested within 3 prospective cohort studies, in New York, Sweden and Italy. Serum or plasma samples had been collected at enrollment and stored at -80 degrees C. A total of 153 cases, diagnosed a median of 5.3 years after blood donation, and 271 matched controls were included. No difference in circulating enterolactone was observed between cases (median, 19.2 nmol/L) and controls (18.5 nmol/L). Adjusting for body mass index, the odds ratio for the top tertile of enterolactone, as compared to the lowest was 1.2 (95% CI, 0.7-2.0; p for trend = 0.53). Lack of association was observed in both pre- and postmenopausal women. No correlation was observed between enterolactone and circulating estrogens or SHBG in healthy postmenopausal women. These results do not support a protective role of circulating lignans, in the range of levels observed, against endometrial cancer

Fat and cholesterol are theorized to promote ovarian carcinogenesis by increasing circulating estrogen levels. Although case-control studies have reported positive associations between total and saturated fat intake and ovarian cancer risk, two cohort studies have observed null associations. Dietary cholesterol and eggs have been positively associated with ovarian cancer risk. A pooled analysis was conducted on 12 cohort studies. Among 523,217 women, 2,132 incident epithelial ovarian cancer cases were identified. Study-specific relative risks (RR) and 95% confidence intervals (CI) were calculated by Cox proportional hazards models, and then pooled using a random effects model. Total fat intake was not associated with ovarian cancer risk (pooled multivariate RR = 1.08, 95% CI 0.86-1.34 comparing > or =45 to 30-<35% of calories). No association was observed for monounsaturated, polyunsaturated, trans-unsaturated, animal and vegetable fat, cholesterol and egg intakes with ovarian cancer risk. A weakly positive, but non-linear association, was observed for saturated fat intake (pooled multivariate RR = 1.29, 95% CI: 1.01-1.66 comparing highest versus lowest decile). Results for histologic subtypes were similar. Overall, fat, cholesterol and egg intakes were not associated with ovarian cancer risk. The positive association for saturated fat intake at very high intakes merits further investigation

OBJECTIVES: The authors assessed whether home and occupational exposure to organic solvents is associated with risk of NHL in women. METHODS: A population-based, incidence case-control study was conducted in upstate New York, involving 376 NHL cases and 463 population controls selected from the Medicare beneficiary files and State driver's license records. Exposure information was obtained by telephone interview. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using an unconditional logistic regression model, adjusting for a number of risk factors for NHL. RESULTS: Overall, history of exposure to organic solvents was not associated with the risk of NHL. A statistically significant increase in risk associated with occupational exposure was observed only for the subjects whose first exposure occurred before 1970 (OR=1.87, 95% CI 1.03-3.40). When occupational and home exposures to paint thinners/turpentine were combined and analyzed together, the risk of NHL associated with any exposure, compared to no exposure at either job or home, was a statistically significantly increased (OR=1.46, 95% CI: 1.05-2.03). This observation was more pronounced for B-cell lymphoma and for low-grade lymphoma with ORs of 1.52 (95 CI: 1.08-2.14) and 2.20 (95% CI; 1.42-3.41), respectively. CONCLUSIONS: The results of this case-control study do support of a major role of organic solvents in the development of NHL among women currently living in the US. However, relatively intensive exposure in past occupations and use of paint thinners/turpentine may deserve further investigation

Prospective cohort studies on breast cancer risk among premenopausal women and insulin-like growth factor I (IGF-I) concentrations have so far included only few cases, and have shown inconsistent relative risk estimates. We pooled 220 cases of breast cancer diagnosed before age 50, and 434 control subjects, from three prospective studies in New York (USA), Umea (Northern Sweden) and Milan (Italy), and we measured IGF-I and insulin-like growth factor binding protein 3 (IGFBP-3) with common enzyme-linked immunosorbent assays. Overall, IGF-I and IGFBP-3 measurements obtained by the common method showed a positive but not significant relationship with breast cancer risk (odds ratios (ORs) 0.90 [95% confidence intervals (95% CI) 0.50-1.62], 1.63 [0.89-2.97], 1.46 [0.78-2.73] and 1.41 [0.75-2.63] for quintiles of IGF-I, and ORs 0.98 [0.54-1.75], 1.06 [0.59-1.91], 1.04 [0.58-1.87] and 1.77 [0.97-3.24] for quintiles of IGFBP-3). Our results give only moderate support for an association of blood IGF-I with breast cancer risk in young women

Because fruits and vegetables are rich in bioactive compounds with potential cancer-preventive actions, increased consumption may reduce the risk of ovarian cancer. Evidence on the association between fruit and vegetable intake and ovarian cancer risk has not been consistent. We analyzed and pooled the primary data from 12 prospective studies in North America and Europe. Fruit and vegetable intake was measured at baseline in each study using a validated food-frequency questionnaire. To summarize the association between fruit and vegetable intake and ovarian cancer, study-specific relative risks (RR) were estimated using the Cox proportional hazards model, and then combined using a random-effects model. Among 560,441 women, 2,130 cases of invasive epithelial ovarian cancer occurred during a maximum follow-up of 7 to 22 years across studies. Total fruit intake was not associated with ovarian cancer risk-the pooled multivariate RR for the highest versus the lowest quartile of intake was 1.06 [95% confidence interval (95% CI), 0.92-1.21; P value, test for trend = 0.73; P value, test for between-studies heterogeneity = 0.74]. Similarly, results for total vegetable intake indicated no significant association (pooled multivariate RR, 0.90; 95% CI, 0.78-1.04, for the highest versus the lowest quartile; P value, test for trend = 0.06; P value, test for between-studies heterogeneity = 0.31). Intakes of botanically defined fruit and vegetable groups and individual fruits and vegetables were also not associated with ovarian cancer risk. Associations for total fruits and vegetables were similar for different histologic types. These results suggest that fruit and vegetable consumption in adulthood has no important association with the risk of ovarian cancer