Biomedical subjects

D M Freedman

Publications and source records attributed to D M Freedman.

At least 19 recordsLinked to original sources

PubMed2007

Mortality due to amyotrophic lateral sclerosis and Parkinson's disease among melanoma patients.

Recent studies in the USA and elsewhere have identified a possible association between Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and melanoma. However, empirical evidence is very limited. We conducted a study of all people diagnosed as having melanoma in Australia since 1982 (n = 127,037). The subjects, excluding those who had died within 12 months of diagnosis, were followed until 31 December 2001. We then compared their mortality risk of ALS and PD to that of the general population. There were a total of 53 ALS deaths and 129 deaths due to PD. Although the absolute risk is small, the melanoma cohort had a risk of death due to ALS 70% higher (standardised mortality ratio = 169.4, 95% CI = 127-221) than the general population, and nearly a 3-fold increased risk of dying from PD (standardised mortality ratio = 266.3, 95% CI = 222-317). These increased risks continued for long-term survivors, arguing against a surveillance effect (particularly for ALS). The consistency of these results in 2 separate populations (Australia and USA) strengthens the evidence for an association between melanoma and each of the 2 neurodegenerative diseases.

Amyotrophic Lateral Sclerosis↗

PubMed2006

Body mass index and all-cause mortality in a nationwide US cohort.

OBJECTIVE: To investigate whether the nature of the relationship between body mass index (BMI (kg/m2)) and all-cause mortality is direct, J- or U-shaped, and whether this relationship changes as people age. DESIGN: Prospective nationwide cohort study of US radiologic technologists (USRT). SUBJECTS: Sixty-four thousand seven hundred and thirty-three female and 19 011 male certified radiation technologists. METHODS: We prospectively followed participants from the USRT study who completed a mail survey in 1983-1989 through 2000. During an average of 14.7 years of follow-up or 1.23 million person-years, 2278 women and 1495 men died. Using Cox's proportional-hazards regression analyses, we analyzed the relationship between BMI and all-cause mortality by gender and by age group (<55 years; > or = 55 years). We also examined risk in never-smokers after the first 5 years of follow-up to limit bias owing to the confounding effects of smoking and illness-related weight loss on BMI and mortality. RESULTS: Risks were generally J-shaped for both genders and age groups. When we excluded smokers and the first 5 year of follow-up, risks were substantially reduced in those with low BMIs. In never-smoking women under the age of 55 years (excluding the initial 5-year follow-up period), risk rose as BMI increased above 21.0 kg/m2, whereas in older women, risk increased beginning at a higher BMI (> or = 25.0 kg/m2). Among younger men who never smoked (excluding the initial 5-year follow-up period), risk began to rise above a BMI of 23.0 kg/m2, whereas in older men, risk did not begin to increase until exceeding a BMI of 30.0 kg/m2. CONCLUSIONS: In younger/middle-aged, but not older, women and men, mortality risks appear directly related to BMI. The more complicated relationship between BMI and mortality in older subjects suggests the importance of assessing whether other markers of body composition better explain mortality risk in older adults.

Adult↗

PubMed2005

Incidence of haematopoietic malignancies in US radiologic technologists.

BACKGROUND: There are limited data on risks of haematopoietic malignancies associated with protracted low-to-moderate dose radiation. AIMS: To contribute the first incidence risk estimates for haematopoietic malignancies in relation to work history, procedures, practices, and protective measures in a large population of mostly female medical radiation workers. METHODS: The investigators followed up 71,894 (77.9% female) US radiologic technologists, first certified during 1926-80, from completion of a baseline questionnaire (1983-89) to return of a second questionnaire (1994-98), diagnosis of a first cancer, death, or 31 August 1998 (731,306 person-years), whichever occurred first. Cox proportional hazards regression was used to compute risks. RESULTS: Relative risks (RR) for leukaemias other than chronic lymphocytic leukaemia (non-CLL, 41 cases) were increased among technologists working five or more years before 1950 (RR = 6.6, 95% CI 1.0 to 41.9, based on seven cases) or holding patients 50 or more times for x ray examination (RR = 2.6, 95% CI 1.3 to 5.4). Risks of non-CLL leukaemias were not significantly related to the number of years subjects worked in more recent periods, the year or age first worked, the total years worked, specific procedures or equipment used, or personal radiotherapy. Working as a radiologic technologist was not significantly linked with risk of multiple myeloma (28 cases), non-Hodgkin's lymphoma (118 cases), Hodgkin's lymphoma (31 cases), or chronic lymphocytic leukaemia (23 cases). CONCLUSION: Similar to results for single acute dose and fractionated high dose radiation exposures, there was increased risk for non-CLL leukaemias decades after initial protracted radiation exposure that likely cumulated to low-to-moderate doses.

Adult↗

PubMed2002

Compartment reconstruction for De Quervain's disease.

A new surgical treatment for De Quervain's disease is presented, in which the anatomy and function of the first dorsal compartment is preserved. Our findings in 11 wrists in ten patients revealed complete relief of the pre-operative symptoms in all instances. The advantages of this technique are its ease, its restoration of normal anatomy, and the prevention of tendon prolapse.

Adult↗

PubMed2002

Sunlight and mortality from breast, ovarian, colon, prostate, and non-melanoma skin cancer: a composite death certificate based case-control study.

OBJECTIVES: To explore whether mortality from female breast, ovarian, colon, and prostate cancer were negatively associated with exposure to sunlight. METHODS: A death certificate based case-control study of mortality was conducted into five cancers: female breast, ovarian, colon, prostate, and non-melanoma skin cancer (as a positive control) to examine associations with residential and occupational exposure to sunlight. Cases were all deaths from these cancers between 1984 and 1995 in 24 states of the United States. Controls, which were age frequency matched to a series of cases, excluded deaths from cancer and certain neurological diseases. Multiple logistic regression was used in a model that included age, sex, race, residential exposure to sunlight (based on region), and socioeconomic status, occupational exposure to sunlight, and physical activity (the last three based on usual occupation). RESULTS: Residential exposure to sunlight was negatively and significantly associated with mortality from female breast, ovarian, prostate, and colon cancer. Only female breast and colon cancer, however, also showed significant negative associations with jobs with the highest occupational exposure to sunlight (odds ratio (OR) 0.82 (95% confidence interval (95% CI) 0.70 to 0.97) for female breast cancer; OR 0.90 (95% CI 0.86 to 0.94) for colon cancer). For both cancers, the negative association with occupational sunlight was greatest in the geographical region of highest exposure to sunlight and was independent of physical activity on the job. Non-melanoma skin cancer, as expected, was positively associated with both residential and occupational sunlight. CONCLUSIONS: In this exploratory study, unlike mortality from non-melanoma skin cancer, mortality from female breast cancer and colon cancer were negatively associated with both residential and occupational sunlight.

Adult↗

PubMed2001

Vascularity of the carpus.

Relatively few studies investigating the vascular patterns of the carpus have been performed. Technical difficulties in identifying small vessels in three dimensions and in determining their location within the thick ligaments about the wrist have led to conflicting anatomic reports. Studies on cadavers in which improved techniques with arterial injection, chemical debridement, and decalcification were used allowed the arterial anatomy of the carpus to be delineated more accurately. The current authors review these arterial patterns, with attention given to the extraosseous and intraosseous vascularities.

Carpal Bones↗

PubMed2001

Household solvent exposures and childhood acute lymphoblastic leukemia.

OBJECTIVES: This study explored the risk of childhood acute lymphoblastic leukemia (ALL) associated with participation by household members in hobbies or other home projects involving organic solvents. METHODS: Participants in this case-control study were 640 subjects with ALL and 640 matched controls. RESULTS: Childhood ALL was associated with frequent (> 4 times/month) exposure to model building (odds ratio [OR] = 1.9; 95% confidence interval [95% CI] = 0.7, 5.8) and artwork using solvents (OR = 4.1; 95% CI = 1.1, 15.1). We also found elevated risk (OR = 1.7; 95% CI = 1.1, 2.7) among children whose mothers lived in homes painted extensively (> 4 rooms) in the year before the children's birth. CONCLUSIONS: In this exploratory study, substantial participation by household members in some common household activities that involve organic solvents was associated with elevated risks of childhood ALL.

Child↗

PubMed2000

Long-term results of volar ligament reconstruction for symptomatic basal joint laxity.

It has been hypothesized that instability of the thumb trapeziometacarpal joint is a major factor in the etiology of degenerative disease. Theoretically, surgically stabilized joints should be subject to less shear force and, hence, will be less likely to develop degenerative changes. The long-term results of volar ligament reconstruction were assessed in 19 patients (24 thumbs). The average age at surgery was 33 years (range, 18-55 years). Twenty-three thumbs were radiographic stage I; a preoperative x-ray was not available in 1. The follow-up period averaged 15 years (range, 10-23 years). At the final follow-up visit 15 thumbs were stage I, 7 were stage II, and 2 were stage III. Fifteen patients were at least 90% satisfied with the results of the surgery. Only 8% of thumbs advanced to radiographic arthritic disease, which compares favorably with the 17% to 33% reported incidence of stage III/IV basal joint arthritis in the general population.

Adolescent↗

PubMed2000

Mortality from multiple sclerosis and exposure to residential and occupational solar radiation: a case-control study based on death certificates.

OBJECTIVES: To explore whether mortality from multiple sclerosis is negatively associated with exposure to sunlight. METHODS: Two case-control studies based on death certificates were conducted for mortality from multiple sclerosis and non-melanoma skin cancer (as a positive control) to examine associations with residential and occupational exposure to sunlight. Cases were all deaths from multiple sclerosis between 1984 and 1995 in 24 states of the United States. Controls, which were age frequency matched to a series of cases, excluded cancer and certain neurological deaths. The effects of occupational exposure to sunlight were assessed among subjects with usual occupations requiring substantial activity, so as to exclude those whose indoor jobs resulted from disabilities subsequent to the onset of the disease. Multiple logistic regression analyses were applied, with adjustment for age, sex, race, and socioeconomic status. RESULTS: Unlike mortality from skin cancer, mortality from multiple sclerosis was negatively associated with residential exposure to sunlight (odds ratio (OR)=0.53 (multiple sclerosis) and OR=1.24 (skin cancer)). Odds ratios for the highest occupational exposure to sunlight were 0.74 (95% confidence interval (95% CI) 0.61 to 0.89) for mortality from multiple sclerosis, compared with 1.21 (1.09 to 1.34) for mortality from non-melanoma skin cancer. The OR was 0.24 for the combined effect of the highest levels of residential and occupational exposure to sunlight on multiple sclerosis, compared with an OR of 1.38 for skin cancer. CONCLUSIONS: In this exploratory study, mortality from multiple sclerosis, unlike mortality from skin cancer, was negatively associated with both residential and occupational exposure to sunlight.

Adult↗

PubMed1999

Tomography versus computed tomography for assessing step off in intraarticular distal radial fractures.

Computed tomography scans have supplanted conventional tomography for many applications and often are considered the imaging study of choice for assessing intraarticular distal radial fractures. Concern about cost containment in healthcare delivery prompts the question of whether the two studies provide comparable information and at what cost. Common intraarticular distal radial fractures were created in 12 lightly embalmed cadaveric specimens. The fractures were fixed with radiolucent Kirschner wires. Articular step off was measured with a caliper. Plain radiographs, computed tomography scans, and trispiral tomograms were obtained of each specimen. Maximal step off was measured blindly by two musculoskeletal radiologists and four hand surgeons. The radiographic measurements were compared with the actual step off and expressed as a positive or negative deviation from the actual value. There was no statistically significant difference between computed tomography scans and tomograms in predicting step off. In addition, the difference between actual and radiographic measurements was insignificant in tomogram readings and different in one of the computed tomography measurements. In the authors' institution, a tomogram costs $200, and a computed tomography scan costs $562. Trispiral tomography is more accurate and cost effective than computed tomography, and thus when available should be considered the imaging modality of choice for assessing articular step off in distal radius fractures.

Analysis of Variance↗

PubMed1999

The effect of beta-carotene supplementation on serum vitamin D metabolite concentrations.

In the alpha-Tocopherol, beta-Carotene Cancer Prevention (ATBC) study, a large randomized placebo-controlled trial designed to test the cancer prevention effects of alpha-tocopherol (50 mg/day) and beta-carotene (20 mg/day), participants receiving supplemental beta-carotene had significantly higher rates of lung cancer than those not receiving beta-carotene. It has been hypothesized that the supplemental beta-carotene may have interfered with the synthesis of vitamin D and that the resulting lower concentrations of vitamin D contributed to the elevated cancer incidence. We evaluated whether supplementation with beta-carotene altered the serum concentrations of either 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D in the ATBC Study, by comparing on-study changes between baseline and follow-up serum samples among 20 randomly selected matched pairs of subjects from the beta-carotene and placebo groups. In a matched-pair analysis, the difference between the changes in both 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D in the beta-carotene supplement and placebo groups were small and statistically nonsignificant. These results provide no evidence that beta-carotene supplementation interferes with the endogenous production of 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D and suggest that it is unlikely that an interaction between supplemental beta-carotene and vitamin D metabolites contributed to the modest increase in lung cancer incidence observed in the ATBC Study.

Age Factors↗

PubMed1998

Iatrogenic posterior tibial nerve division during ankle arthroscopy.

Ankle arthroscopy has been increasingly applied to the diagnostic and therapeutic treatment of ankle disorders. Owing to the complex cutaneous anatomy of the ankle, neurological injuries are a potential complication of this procedure. All reports of neurological complications resulting from ankle arthroscopy have attributed them to use of a distractor pin or to portal placement. Several authors have noted the possibility of damage to the deep peroneal nerve from the use of motorized arthroscopic tools within the anterior ankle joint capsule. We present what we believe to be the first reported case of complete division of the posterior tibial nerve resulting from an apparently overaggressive intra-articular manipulation during ankle arthroscopy performed for loose body removal.

Ankle Injuries↗

PubMed1998

Right versus left symmetry of ulnar variance. A radiographic assessment.

One hundred skeletally mature healthy volunteers underwent standardized bilateral posteroanterior radiographs in unloaded (static) and loaded (dynamic) conditions to determine the symmetry of ulnar variance. The mean age was 32 +/- 9 years (range, 19-61 years), with 58 women and 42 men. Ulnar variance was measured to the closest 0.5 mm using the method of perpendiculars. Three separate measurements were made of each radiograph in a blinded fashion by the same investigator. An intraobserver standard deviation of 0.21 was used to calculate a 95% tolerance interval of 0.7 mm (rounded up to 1 mm) as a measure of significance. The average static ulnar variance was -0.13 +/- 1.5 mm on the left and -0.29 +/- 1.6 mm on the right. The average dynamic ulnar variance was 0.93 +/- 1.5 mm on the left and 0.82 +/- 1.5 mm on the right. When compared individually, there was a greater than or equal to 1 mm side to side difference in 37% of volunteers under static and 38% under dynamic conditions. There were no significant correlations between ulnar variance measurements and patient age, gender, race, or handedness. Use of the normal wrist radiograph as a baseline for static radial length measurements is valid in only 63% of cases.

Adult↗

PubMed1997

Residential and occupational exposure to sunlight and mortality from non-Hodgkin's lymphoma: composite (threefold) case-control study.

OBJECTIVE: To determine whether non-Hodgkin's lymphoma mortality is associated with sunlight exposure. DESIGN: Three case-control studies based on death certificates of non-Hodgkin's lymphoma, melanoma, and skin cancer mortality examining associations with potential sunlight exposure from residence and occupation. SETTING: 24 states in the United States. SUBJECTS: All cases were deaths from non-Hodgkin's lymphoma, melanoma, and non-melanotic skin cancer between 1984 and 1991. Two age, sex, and race frequency matched controls per case were selected from non-cancer deaths. MAIN OUTCOME MEASURES: Odds ratios for non-Hodgkin's lymphoma, melanoma, and skin cancer from residential and occupational sunlight exposure adjusted for age, sex, race, socioeconomic status, and farming occupation. RESULTS: Non-Hodgkin's lymphoma mortality was not positively associated with sunlight exposure based on residence. Both melanoma and skin cancer were positively associated with residential sunlight exposure. Adjusted odds ratios for residing in states with the highest sunlight exposure were 0.83 (95% confidence interval 0.81 to 0.86) for non-Hodgkin's lymphoma, 1.12 (1.06 to 1.19) for melanoma, and 1.30 (1.18 to 1.43) for skin cancer. In addition, non-Hodgkin's lymphoma mortality was not positively associated with occupational sunlight exposure (odds ratio 0.88; 0.81 to 0.96). Skin cancer was slightly positively associated with occupational sunlight exposure (1.14; 0.96 to 1.36). CONCLUSIONS: Unlike skin cancer and to some extent melanoma, non-Hodgkin's lymphoma mortality was not positively associated with exposure to sunlight. The findings do not therefore support the hypothesis that sunlight exposure contributes to the rising rates of non-Hodgkin's lymphoma.

Adult↗

PubMed1997

Bladder cancer and drinking water: a population-based case-control study in Washington County, Maryland (United States).

A population-based case-control study was conducted in Washington County, Maryland (United States) to explore the association between incident bladder cancer and exposure to drinking water from chlorinated surface sources. Cancer cases were White residents, enumerated in a 1975 county census and reported to the Washington County Cancer Registry (n = 294) between 1975 and 1992. White controls, frequency matched by age (+/- 5 years) and gender, were selected randomly from the census (n = 2,326). Households receiving municipal water, which generally derived from chlorinated surface waters, were treated as having 'high exposure' and all others, as 'low exposure.' Duration of exposure to type of drinking water was based on length of residence in the census household prior to 1975. Odds ratios (OR) were calculated using logistic regression methods, adjusting for age, gender, tobacco use, and urbanicity. Bladder cancer risk was associated weakly in the general population with duration of exposure to municipal water. The association was limited to those who had smoked cigarettes. In ever-smokers compared with never-smokers with low exposure, the adjusted ORs for bladder cancer risk with increasing exposure were 1.3, 1.4, 1.4, 1.7, 2.2, 2.8, respectively, for 0, 1-10, 11-20, 21-30, 31-40, > 40 years' exposure duration. The ORs in smokers were not diminished after adjusting for smoking history and intensity.

Adult↗

PubMed1996

Heterotopic ossification following total knee arthroplasty requiring surgical excision.

We present a case of progressive heterotopic ossification (HO) after cementless total knee arthroplasty causing painful stiffness that was treated with surgical excision. The patient had few risk factors associated with HO, including minimal anterior notching and dissection of the distal femoral cortex. The patient did undergo manipulation; however, this occurred after the diagnosis of HO was made. This report documents a rare case of HO following total knee arthroplasty that required surgical excision.

Humans↗

PubMed1995

Metastatic breast carcinoma to the os calcis presenting as heel pain.

A 47-year-old woman who had been treated for breast carcinoma 11 years previously developed significant heel pain of unclear etiology, which ultimately proved to be metastatic adenocarcinoma. A low index of suspicion and falsely negative plain radiographs contributed to a delay in diagnosis. No other osseous metastases besides those to the foot were identifiable at the time of diagnosis. Breast carcinoma is one of the most common malignancies and frequently metastasizes to bone. Despite this, metastases to the hands or feet (acrometastases) have been identified in only a few cases. It is likely that acrometastases are more common than reported but unrecognized.

Adenocarcinoma↗

PubMed1994

Ipsilateral hip and knee dislocation.

Hip and knee dislocations individually are two of the relatively limited orthopaedic emergencies. Long-term results of treatment of these two types of injury are associated with avascular necrosis of the femoral head, knee instability, and knee stiffness. Correct early diagnosis, including arteriography in the case of knee dislocation, is crucial. Prompt treatment consisting of closed or open reduction of the dislocations is necessary. Additional treatment involving knee ligament reconstruction is warranted to maximize knee function in healthy, active patients. Simultaneous occurrence of ipsilateral hip and knee dislocations is a particularly morbid injury. We report such a case to emphasize that early, aggressive treatment and extensive physical therapy can result in a functional and painless lower extremity.

Adult↗