Biomedical subjects

Michael Manno

Publications and source records attributed to Michael Manno.

11 recordsLinked to original sources

PubMed2007

Dermatologist and family practitioner practice patterns for occupational contact dermatitis.

Medical practitioners have a role in the recognition of occupational contact dermatitis. The longer the duration of symptoms before diagnosis, the poorer the outcome. Our objective was to understand practice patterns, barriers and needs for early diagnosis of occupational contact dermatitis. A survey to obtain information on practice patterns was developed based on the literature and interviews with dermatologists and family practitioners. The survey was sent to all dermatologists and a random sample of 600 family practitioners in Ontario. Fifty-seven per cent of dermatologists and 9% of family practitioners report seeing more than 20 patients per year with occupational contact dermatitis. The majority of practitioners report taking a workplace exposure history. Barriers to taking a workplace exposure history include time constraints and lack of knowledge. Reasons for referral to specialists include a lack of expertise, testing facilities and knowledge about workers' compensation, time constraints and inadequate reimbursement, whereas lack of access to specialists is a barrier for referral. Although most practitioners identify a need for further education, a low volume of patients and time constraints are key barriers to continuing education. Opportunities are identified to improve educational initiatives and health services delivery for occupational contact dermatitis, tailored to each practitioner group.

Dermatitis, Allergic Contact↗

PubMed2006

Reducing musculoskeletal burden through ergonomic program implementation in a large newspaper.

OBJECTIVES: To assess the impact of a workplace ergonomic program to reduce musculoskeletal burden among newspaper employees and to understand relationships among participation, risk factor changes and health status within an employee cohort. METHODS: We conducted repeat cross-sectional surveys, with 1,003 employees from all major departments in 1996 and 813 in 2001, generating a cohort of 433 participants in both surveys. Elements of the ergonomic program included employee RSI (repetitive strain injury) training, pro-active assessment of workstations and workstation modifications, and encouragement of early treatment through on-site physiotherapy. Potential risk factors included biomechanical and work organizational aspects of office work. Health status measures included pain intensity and the Work-Disability of the Arm, Shoulder, and Hand (DASH). Repeat cross-sectional analyses incorporated modifications for shared variance. For the cohort, a theory of change informed path analyses using MPLUS. RESULTS: Among respondents in 2001, 69% reported participation in RSI training and 56% had workstation assessments. Among those with pain, 57% had consulted a health practitioner, including the on-site physiotherapist. In repeat cross-sectional analyses, the proportion reporting moderate pain or worse, at least once per month or for longer than 1 week, declined from 20 to 16% (p=0.01). Among the cohort, pain intensity and work disability in 1996 were the strongest predictors of 2001 health status (both p<0.001). Stable or increased supervisor awareness and concern about RSI was associated with decreased pain in 2001(p<0.01). Participation in RSI training was associated with increases in decision latitude (p<0.05), which themselves were associated with decreased work disability in 2001 (p<0.05). Increased time mousing was associated with increases in work disability (p<0.05). CONCLUSIONS: Implementation of a worksite ergonomics program was associated with a reduction in frequent and severe pain in the workforce. Changes in work disability were affected by multiple factors.

Adult↗

PubMed2006

Dietary phytoestrogen intake is associated with reduced colorectal cancer risk.

Evidence suggests dietary phytoestrogens may reduce the risk of certain hormonal cancers (e.g. breast and prostate). There is a paucity of data regarding phytoestrogens and colorectal cancer risk. Phytoestrogens are plant compounds with estrogen-like activities. Main classes include isoflavones (found in legumes such as soy) and lignans (found in grains, seeds, nuts, fruits, and vegetables). Although isoflavones have dominated phytoestrogen cancer research, lignans may be more relevant to North American diets. Food questionnaires and analytic databases have recently been modified to incorporate some lignan information. We conducted a case-control study to evaluate the association between phytoestrogen intake and colorectal cancer risk. Colorectal cancer cases were diagnosed in 1997-2000, aged 20-74 y, identified through the population-based Ontario Cancer Registry, and recruited by the Ontario Familial Colorectal Cancer Registry. Controls were a sex and age-group matched random sample of the population of Ontario. Epidemiologic and food frequency questionnaires were completed by 1095 cases and 1890 control subjects. Multivariate logistic regression analysis was used to obtain adjusted odds ratio (OR) estimates. Dietary lignan intake was associated with a significant reduction in colorectal cancer risk [OR (T3 vs. T1) = 0.73; 95% CI: 0.56, 0.94], as was isoflavone intake [OR (T3 vs. T1) = 0.71; 95% CI: 0.58, 0.86]. We evaluated interactions between polymorphic genes that encode enzymes possibly involved in metabolism of phytoestrogens (CYPs, catechol O-methyl transferase, GSTs, and UGTs) and found no significant effect modification with respect to phytoestrogen intake. This finding that phytoestrogen intake may reduce colorectal cancer risk is important, because dietary intake is potentially modifiable.

Colorectal Neoplasms↗

PubMed2006

Prognosis in soft tissue disorders of the shoulder: predicting both change in disability and level of disability after treatment.

BACKGROUND AND PURPOSE: Clinicians often are faced with questions about prognosis and outcome of shoulder disorders. The purpose of this study was to identify predictors of both change in disability and level of disability following physical therapy treatment. SUBJECTS: The subjects were consecutive patients (n=361) who were receiving physical therapy for soft tissue shoulder disorders. METHODS: Clinical response to physical therapy, which was measured using the Disabilities of the Arm, Shoulder, and Hand (DASH) measure, was assessed over 12 weeks. The 28 independent baseline predictors included demographics, disorder-related and disability measures, medication use, clinical findings, and expectations for recovery. Multiple linear regression techniques were used. RESULTS: Predictors of greater disability at discharge were: higher initial disability, therapist prediction of restricted activities at discharge, workers' compensation claim, older age, and being female. Predictors of greater improvement in disability were: shoulder surgery, higher pain intensity, shorter duration of symptoms, younger age, and poorer general physical health (measured using the 36-Item Short-Form Health Survey [SF-36]). DISCUSSION AND CONCLUSIONS: Prognostic factors differ depending on the format of the outcome. Only age was significant in both models.

Adolescent↗

PubMed2005

Colorectal screening is associated with reduced colorectal cancer risk: a case-control study within the population-based Ontario Familial Colorectal Cancer Registry.

OBJECTIVE: This is the first study to evaluate the association between colonic screening and colorectal cancer risk among Canadians. METHODS: A case-control study was conducted. Cases were diagnosed with cancer of the colorectum, between 1997 and 2000, aged 20 to 74 years, identified through the population-based Ontario Cancer Registry and recruited by the Ontario Familial Colorectal Cancer Registry. Controls were a sex- and age-matched random sample of the population of Ontario. 971 cases and 1944 controls completed questionnaires (including colorectal screening history and many risk factors). Multivariate logistic regression analysis was used to obtain adjusted odds ratios (OR) estimates. RESULTS: Having had a fecal occult blood screen was associated with reduced colorectal cancer risk (OR=0.76; 95% confidence interval (CI): 0.59, 0.97). Having had a screening sigmoidoscopy was associated with a halving of colorectal cancer risk (OR = 0.52; 95% CI: 0.34, 0.80). Having had a screening colonoscopy did not significantly reduce colorectal cancer risk (OR = 0.69; 95% CI: 0.44, 1.07); however, having had either screening endoscopy was associated with a significant reduction in colorectal cancer risk (OR = 0.62; 95% CI: 0.44, 0.87). Findings differed slightly by anatomic sub-site (proximal and distal colorectum). CONCLUSIONS: We report a reduction in colorectal cancer risk among persons who underwent colorectal cancer screening; in particular, sigmoidoscopy. Findings are of great importance for the prevention of colorectal cancer.

Adult↗

PubMed2005

Methods to account for attrition in longitudinal data: do they work? A simulation study.

Attrition threatens the internal validity of cohort studies. Epidemiologists use various imputation and weighting methods to limit bias due to attrition. However, the ability of these methods to correct for attrition bias has not been tested. We simulated a cohort of 300 subjects using 500 computer replications to determine whether regression imputation, individual weighting, or multiple imputation is useful to reduce attrition bias. We compared these results to a complete subject analysis. Our logistic regression model included a binary exposure and two confounders. We generated 10, 25, and 40% attrition through three missing data mechanisms: missing completely at random (MCAR), missing at random (MAR) and missing not at random (MNAR), and used four covariance matrices to vary attrition. We compared true and estimated mean odds ratios (ORs), standard deviations (SDs), and coverage. With data MCAR and MAR for all attrition rates, the complete subject analysis produced results at least as valid as those from the imputation and weighting methods. With data MNAR, no method provided unbiased estimates of the OR at attrition rates of 25 or 40%. When observations are not MAR or MCAR, imputation and weighting methods may not effectively reduce attrition bias.

Bias↗

PubMed2005

Association between subject factors and colorectal cancer screening participation in Ontario, Canada.

Colorectal cancer screening reduces colorectal cancer incidence and mortality. This population-based study was conducted to evaluate (i) the association between subject factors and colorectal screening participation and (ii) the lifetime prevalence of colorectal screening among the general population of Ontario, Canada. Population-based controls were recruited by the Ontario Familial Colorectal Cancer Registry during 1998-2000. The 1944 persons completed an epidemiologic questionnaire. Descriptive statistics were computed and step-wise multivariate logistic regression was used to estimate odds ratios and 95% confidence intervals. Overall, 23% of persons greater than 50 years of age reported ever having had colorectal cancer screening; 17% reported fecal occult blood test (FOBT), 6% sigmoidoscopy, and 4% colonoscopy. Family history of colorectal cancer, increased age, higher household income, and use of hormone replacement therapy (among women) were all significantly associated with ever having had colorectal cancer screening. The low prevalence of colorectal cancer screening among the target population suggests the need for an increased awareness of the public health importance of colorectal cancer screening.

Adult↗

PubMed2005

Association between colonic screening, subject characteristics, and stage of colorectal cancer.

OBJECTIVES: Colorectal cancer remains a significant cause of mortality and morbidity in North America. Colorectal cancer survival is highly dependent on stage at diagnosis, therefore it is important to identify factors related to stage. This study evaluated the association between subject factors (e.g., colonic screening, family history) and stage of colorectal cancer at diagnosis. METHODS: Population-based colorectal cancer cases recruited by the Ontario Familial Colon Cancer Registry between 1997 and 1999 were staged according to the tumor-nodal-metastasis (TNM) staging system and classified as early (TNM I/II) or late (TNM III/IV) stage. Epidemiologic information and stage was available for 768 cases. Multivariate logistic regression was used to obtain odds ratios (OR) estimates. RESULTS: Having had screening endoscopy reduced the risk of late stage diagnosis (OR = 0.46, 95% CI 0.22-0.98). Being older (>45 yr) was associated with a reduced risk of late stage cancer (OR = 0.36, 95% CI 0.18-0.74), as was having a first degree relative with colorectal cancer (OR =0.66, 95% CI 0.46-0.95). Rural residence (OR = 1.48, 95% CI 1.01-2.17) and non-white ethnicity (OR = 3.34, 95% CI 1.20-9.36) were associated with an increased risk of late stage cancer. CONCLUSIONS: Several factors are independently associated with late stage colorectal cancer. Colorectal cancer screening awareness and education programs need to consider targeting persons most likely to present with late stage colorectal cancer.

Adult↗

PubMed2004

Association between biallelic and monoallelic germline MYH gene mutations and colorectal cancer risk.

The MutY human homologue (MYH) gene encodes a member of the base excision repair pathway that is involved in repairing oxidative damage to DNA. Two germline MYH gene mutations that result in Myh proteins containing amino acid substitutions Y165C and G382D (hereafter called the Y165C and G382D mutations) are associated with adenomatous poly-posis and colorectal cancer among patients from several European poly-posis registries. We used a population-based series of 1238 colorectal cancer patients and 1255 healthy control subjects from Ontario, Canada, to examine the risk of colorectal cancer among biallelic and monoallelic germline MYH Y165C and G382D mutation carriers. The entire MYH gene coding region was screened in all MYH Y165C and G382D mutation carriers. Compared with noncarriers, biallelic and monoallelic germline MYH gene mutation carriers had an increased risk of colorectal cancer and were more likely to have first-or second-degree relatives with colorectal cancer (relative risk = 1.54, 95% confidence interval = 1.10 to 2.16). The increased risk of colorectal cancer in biallelic and monoallelic MYH gene mutation carriers was not consistently associated with the development of multiple adenomatous polyps. Loss of heterozygosity in at least one of four loci in MYH was detected in eight (47%) of 17 colorectal tumors from monoallelic MYH gene mutation carriers but in only two (20%) of 10 colorectal tumors from biallelic MYH gene mutation carriers. These two MYH gene mutations may account for a substantial fraction of hereditary colorectal cancer.

Adenomatous Polyposis Coli↗

PubMed2004

Loss to follow-up in cohort studies: how much is too much?

Loss to follow-up is problematic in most cohort studies and often leads to bias. Although guidelines suggest acceptable follow-up rates, the authors are unaware of studies that test the validity of these recommendations. The objective of this study was to determine whether the recommended follow-up thresholds of 60-80% are associated with biased effects in cohort studies. A simulation study was conducted using 1000 computer replications of a cohort of 500 observations. The logistic regression model included a binary exposure and three confounders. Varied correlation structures of the data represented various levels of confounding. Differing levels of loss to follow-up were generated through three mechanisms: missing completely at random (MCAR), missing at random (MAR) and missing not at random (MNAR). The authors found no important bias with levels of loss that varied from 5 to 60% when loss to follow-up was related to MCAR or MAR mechanisms. However, when observations were lost to follow-up based on a MNAR mechanism, the authors found seriously biased estimates of the odds ratios with low levels of loss to follow-up. Loss to follow-up in cohort studies rarely occurs randomly. Therefore, when planning a cohort study, one should assume that loss to follow-up is MNAR and attempt to achieve the maximum follow-up rate possible.

Bias↗

PubMed2002

Transitions in self-reported musculoskeletal pain and interference with activities among newspaper workers.

Active surveillance of symptoms and disability due to musculoskeletal disorders (MSD) in working populations can map individual transitions in symptom intensity or disability level. Using repeat surveys, this study examined if aetiological risk factors for new symptoms or disability, measured by interference with activities, were similar to prognostic risk factors for subsequent outcomes of symptoms and disability. This paper reports on 379 Toronto newspaper workers who completed questionnaires in 1996 and 1997. Questions on pain/discomfort during the last year, episode frequency and duration formed the basis for constructing three mutually exclusive symptom levels: noncases (Level 1); mild cases (Level 2); and more severe or frequent pain cases (Level 3). A similar construction of overall interference levels was based on the frequency with which musculoskeletal pain/discomfort interfered with daily, recreational, social and family activities, or ability to do one's job during the previous 12 months. The last was also examined as work interference alone. Levels of symptoms were cross-tabulated by overall and work interference at the two time points and Markov models of transitions between states were formulated. Results indicate that period prevalence of symptoms and overall interference increased between phases, though only significantly for symptoms (Levels 2 and 3, 65.7-70.7%, p = 0.04), while work interference was unchanged (17.9-17.0%). Equivalent proportions of workers improved as worsened in symptoms (21.1 and 22.4%, respectively), overall interference (16.7 and 17.8%), and work interference (7.4 and 6.6%). The only significant predictor for those without work interference at time one was job tenure, which was protective against work interference (Odds Ratio (OR) 1.06, 95% Confidence Interval (CI) 1.01-1.12). Among those who had more severe/frequent symptoms at time one, lack of improvement over time was predicted by longer job tenure (OR = 0.92 per year, CI: 0.87-0.97), greater psychological demands of work (OR = 0.65 per point, CI: 0.51-0.84) and marginally by greater upper extremity disability score. At time one, women with work interference were more likely to have persistent interference at time two (OR = 7.22, CI: 1.57-33.20). Suggestive findings included opposite effects of social support at work: reduced risk of development of new symptoms but increased risk of persistence at the highest symptom level.

Activities of Daily Living↗