Search PubMed⌕ Search

Biomedical subjects

T J Thompson

Publications and source records attributed to T J Thompson.

At least 19 recordsLinked to original sources
PubMed2006

Single-center experience using three shockwave lithotripters with different generator designs in management of urinary calculi.

PURPOSE: We retrospectively reviewed the treatment outcomes of extracorporeal shockwave lithotripsy (SWL) in a single center using either the Wolf Piezolith 2300 (a piezoelectric lithotripter), the Dornier MPL9000 (an electrohydraulic lithotripter), or the Dornier Compact Delta (an electromagnetic lithotripter) from January 1992 to June 2002. PATIENTS AND METHODS: A series of 3123 (1449 Piezolith 2300, 780 MPL9000, and 894 Compact Delta) solitary radiopaque urinary stones of < or =15 mm receiving primary SWL were identified. "Stone free" was defined as the absence of evidence of stone on plain radiography. Treatment outcomes were assessed by the stone-free rate 3 months after one treatment session, the retreatment rate, the auxiliary procedure rate, the complication rate, and the effectiveness quotient (EQ). In order to have a better assessment of the efficacy of individual lithotripters, multiple logistic regression was performed to control various factors affecting treatment outcomes, including lithotripter-type, patients' sex and age, history of previous SWL, the stone characteristics (side, site, and size), and the presence of a stent or nephrostomy tube. RESULTS: There were significant differences in the stone site distribution and mean stone size among the three groups. The overall EQ for the Piezolith 2300, MPL9000, and Compact Delta were 0.345, 0.303, and 0.257, respectively. However, using the multiple logistic regression model, the adjusted odds ratio (AOR) of a patient being stone-free after 3 month for the Piezolith 2300 and MPL9000 (using the Compact Delta as the referent category) were 1.38 (95% CI 1.15, 1.65) and 1.72 (95% CI 1.39, 2.11), respectively. Patients treated using the MPL9000 had significantly less re-treatment (AOR = 0.57; 95% CI 0.48, 0.69) than the other groups. No significant difference in the auxiliary procedure rate and complication rate for the three machines was observed. CONCLUSION: Based on multivariate analysis results, the Dornier MPL9000 had the best treatment outcomes in terms of stone-free rate and re-treatment rate among the three lithotripters.

Electromagnetic Phenomena↗
PubMed2004

Comparison of 2 generations of piezoelectric lithotriptors using matched pair analysis.

PURPOSE: The Piezolith 3000 (Richard Wolf, Knittlingen, Germany) is the newest piezoelectric lithotriptor. Using a matched pair analysis model we compared treatment outcomes of this machine with those of an older generation Piezolith 2300 lithotriptor (Richard Wolf). MATERIALS AND METHODS: Patients with solitary, radio-opaque urinary calculi undergoing primary lithotripsy using the Piezolith 3000 were identified. All patients had a 3-month followup. These patients were matched with those from our database treated between 1992 and 1999 with a Piezolith 2300. Patients were initially matched for gender, side and site of the stone. For stones other than those in the lower calix and lower ureter, matching was performed for size in terms of maximum and minimum diameter of the index stone. Additional anatomical factors of caliceal pelvic height and vertical distance of the lower ureteral stone from pubic symphysis were also measured. Thereafter stones with size +/- 1 mm of the index stone were selected and the stone with the best matched anatomical factors was chosen. The initial stone fragmentation rate and stone-free rates at 3 months in the matched pairs were then compared. RESULTS: A total of 25 matched pairs were found between October 2002 and December 2002. There was no statistical difference between the initial fragmentation rate for the Piezolith 3000 (68%) and the Piezolith 2300 (84%, McNemar's test p = 0.388). The stone-free rate at 3 months for the Piezolith 3000 and the Piezolith 2300 were 36% and 48%, respectively, again with no statistical difference (McNemar's test p = 0.581). CONCLUSIONS: Despite significant design changes and technical modifications, the new piezoelectric lithotriptor does not appear to provide a better treatment outcome than the older generation machine.

Equipment Design↗
PubMed2002

Body weight and obesity in adults and self-reported abuse in childhood.

BACKGROUND: Little is known about childhood factors and adult obesity. A previous study found a strong association between childhood neglect and obesity in young adults. OBJECTIVE: To estimate associations between self-reported abuse in childhood (sexual, verbal, fear of physical abuse and physical) adult body weight, and risk of obesity. DESIGN: Retrospective cohort study with surveys during 1995-1997. PATIENTS: A total of 13,177 members of California health maintenance organization aged 19-92 y. MEASUREMENTS: Body weight measured during clinical examination, followed by mailed survey to recall experiences during first 18 y of life. Estimates adjusted for adult demographic factors and health practices, and characteristics of the childhood household. RESULTS: Some 66% of participants reported one or more type of abuse. Physical abuse and verbal abuse were most strongly associated with body weight and obesity. Compared with no physical abuse (55%), being 'often hit and injured' (2.5%) had a 4.0 kg (95% confidence interval: 2.4-5.6 kg) higher weight and a 1.4 (1.2-1.6) relative risk (RR) of body mass index (BMI) > or = 30. Compared with no verbal abuse (53%), being 'often verbally abused' (9.5%) had an RR of 1.9 (1.3-2.7) for BMI > or = 40. The abuse associations were not mutually independent, however, because the abuse types strongly co-occurred. Obesity risk increased with number and severity of each type of abuse. The population attributable fraction for 'any mention' of abuse (67%) was 8% (3.4-12.3%) for BMI > or = 30 and 17.3% (-1.0-32.4%) for BMI > or = 40. CONCLUSIONS: Abuse in childhood is associated with adult obesity. If causal, preventing child abuse may modestly decrease adult obesity. Treatment of obese adults abused as children may benefit from identification of mechanisms that lead to maintenance of adult obesity.

Adult↗
PubMed2001

Population-based estimates of mortality associated with diabetes: use of a death certificate check box in North Dakota.

OBJECTIVES: Overall and cause-specific mortality among persons with diabetes in North Dakota was estimated and compared with estimates from previous population-based studies. METHODS: Data were derived from North Dakota death certificate data, which included unique information on decedents' diabetes status and Behavioral Risk Factor Surveillance System estimates of the diabetic and nondiabetic adult populations of North Dakota. RESULTS: The risk of death among adults with diabetes was 2.6 (2.2, 2.9) times that of adults without diabetes. Relative risks of death among adults with diabetes were at least twice as high for heart disease, cerebrovascular disease, accidents and adverse events, and kidney disease and 70% to 80% higher for pneumonia and influenza, malignant neoplasms, arterial disease, and other causes. Risks remained substantial in the oldest age group. These findings are comparable to results of other population-based studies. CONCLUSIONS: Diabetes status information enhanced the usefulness of death certificate data in examining mortality associated with diabetes and confirms that the effect of diabetes on death is substantial.

Adult↗
PubMed2001

Performance of recommended screening tests for undiagnosed diabetes and dysglycemia.

OBJECTIVE: To evaluate the performance, in settings typical of opportunistic and community screening programs, of screening tests currently recommended by the American Diabetes Association (ADA) for detecting undiagnosed diabetes. RESEARCH DESIGN AND METHODS: Volunteers aged > or =20 years without previously diagnosed diabetes (n = 1,471) completed a brief questionnaire and underwent recording of postprandial time and measurement of capillary blood glucose (CBG) with a portable sensor. Participants subsequently underwent a 75-g oral glucose tolerance test; fasting serum glucose (FSG) and 2-h postload serum glucose (2-h SG) concentrations were measured. The screening tests we studied included the ADA risk assessment questionnaire, the recommended CBG cut point of 140 mg/dl, and an alternative CBG cut point of 120 mg/dl. Each screening test was evaluated against several diagnostic criteria for diabetes (FSG > or =126 mg/dl, 2-h SG > or =200 mg/dl, or either) and dysglycemia (FSG > or =110 mg/dl, 2-h SG > or =140 mg/dl, or either). RESULTS: Among all participants, 10.7% had undiagnosed diabetes (FSG > or =126 or 2-h SG > or =200 mg/dl), 52.1% had a positive result on the questionnaire, 9.5% had CBG > or =140 mg/dl, and 18.4% had CBG > or =120 mg/dl. The questionnaire was 72-78% sensitive and 50-51% specific for the three diabetes diagnostic criteria; CBG > or =140 mg/dl was 56-65% sensitive and 95-96% specific, and CBG > or =120 mg/dl was 75-84% sensitive and 86-90% specific. CBG > or =120 mg/dl was 44-62% sensitive and 89-90% specific for dysglycemia. CONCLUSIONS: Low specificity may limit the usefulness of the ADA questionnaire. Lowering the cut point for a casual CBG test (e.g., to 120 mg/dl) may improve sensitivity and still provide adequate specificity.

Adult↗
PubMed2001

Projection of diabetes burden through 2050: impact of changing demography and disease prevalence in the U.S.

OBJECTIVE: To project the number of people with diagnosed diabetes in the U.S. through 2050, accounting for changing demography and diabetes prevalence rates. RESEARCH DESIGN AND METHODS: We combined age-, sex-, and race-specific diagnosed diabetes prevalence rates-predicted from 1980-1998 trends in prevalence data from the National Health Interview Survey-with Bureau of Census population demographic projections. Sensitivity analyses were performed by varying both prevalence rate and population projections. RESULTS: The number of Americans with diagnosed diabetes is projected to increase 165%, from 11 million in 2000 (prevalence of 4.0%) to 29 million in 2050 (prevalence of 7.2%). The largest percent increase in diagnosed diabetes will be among those aged > or =75 years (+271% in women and +437% in men). The fastest growing ethnic group with diagnosed diabetes is expected to be black males (+363% from 2000-2050), with black females (+217%), white males (+148%), and white females (+107%) following. Of the projected 18 million increase in the number of cases of diabetes in 2050, 37% are due to changes in demographic composition, 27% are due to population growth, and 36% are due to increasing prevalence rates. CONCLUSIONS: If recent trends in diabetes prevalence rates continue linearly over the next 50 years, future changes in the size and demographic characteristics of the U.S. population will lead to dramatic increases in the number of Americans with diagnosed diabetes.

Adolescent↗
PubMed2000

Intentional weight loss and mortality among overweight individuals with diabetes.

OBJECTIVE: To estimate the effect of intentional weight loss on mortality in overweight individuals with diabetes. RESEARCH DESIGN AND METHODS: We performed a prospective analysis with a 12-year mortality follow-up (1959-1972) of 4,970 overweight individuals with diabetes, 40-64 years of age, who were enrolled in the American Cancer Society's Cancer Prevention Study I. Rate ratios (RRs) were calculated, comparing overall death rates, and death from cardiovascular disease (CVD) or diabetes in individuals with and without reported intentional weight loss. RESULTS: Intentional weight loss was reported by 34% of the cohort. After adjustment for initial BMI, sociodemographic factors, health status, and physical activity, intentional weight loss was associated with a 25% reduction in total mortality (RR = 0.75; 95% CI 0.67-0.84), and a 28% reduction in CVD and diabetes mortality (RR = 0.72; 0.63-0.82). Intentional weight loss of 20-29 lb was associated with the largest reductions in mortality (approximately 33%). Weight loss >70 lb was associated with small increases in mortality CONCLUSIONS: Intentional weight loss was associated with substantial reductions in mortality in this observational study of overweight individuals with diabetes.

Adult↗
PubMed1999

Estimating prevalence of type 1 and type 2 diabetes in a population of African Americans with diabetes mellitus.

The pathogenesis, treatment, and outcomes of type 1 and type 2 diabetes differ. Current surveys derive population-based estimates of diabetes prevalence by type using limited clinical information and applying classification rules developed in white populations. How well these rules perform when deriving similar estimates in African American populations is unknown. For this study, data were collected on a group of African Americans with diabetes who enrolled at the Diabetes Unit of Grady Memorial Hospital in Atlanta, Georgia, from April 16, 1991, to November 1, 1996. The data were used to develop some simple classification rules for African Americans based on a classification tree and a logistic regression model. Sensitivities and specificities, in which fasting C-peptide was used as the gold standard, were determined for these rules and for two current rules developed in mostly white, non-Hispanic populations. Rules that yielded precise (minimum variance unbiased) estimates of the prevalence of type 1 diabetes were preferred. The authors found that a rule based on the logistic regression model was best for estimating type 1 prevalences ranging from 1% to 17%. They concluded that simple classification rules can be used to estimate prevalence of diabetes by type in African American populations and that the optimal rule differs somewhat from the current rules.

Adult↗
PubMed1999

The use of population attributable risk to estimate the impact of prevention and early detection of type 2 diabetes on population-wide mortality risk in US males.

The Population Attributable Risk (PAR) represents the proportion of the deaths (in a specified time) in the whole population that may be preventable if a cause of mortality were totally eliminated. This population-based measure was used to assess the potential impact of three public health interventions for type 2 diabetes (early detection + standard therapy; early detection + intensive therapy; and primary prevention) on the mortality risk from all causes and from cardiovascular (CVD) diseases. Potential reduction in mortality risks for several levels of compliance or implementation (25%, 50%, 75%, 100%) for each intervention were also estimated. Results suggest that among males aged 45-74 years, the interventions may have greater population-wide impact on total deaths among black males, and greater impact on the CVD deaths among white males. Overall, primary prevention (reduction in all-cause mortality 6.2-10.0%, and CVD mortality 7.9-9.0%) may offer greater marginal benefit than screening and early treatment (reduction in all-cause mortality 3.5-8.3%, and CVD mortality 2.8-8.6%). Often the question facing policy makers is not simply whether to but how much of an intervention is worth implementing? Estimated benefits for various intensities of intervention (as provided) may be useful to assess the likely marginal benefits of each intervention, and can be especially useful if combined with estimated marginal costs.

Black or African American↗
PubMed1999

To determine whether the temperature of 2% lignocaine gel affects the initial discomfort which may be associated with its instillation into the male urethra.

OBJECTIVE: To determine whether the temperature of 2% lignocaine hydrochloride gel affects the initial discomfort during instillation into the male urethra. PATIENTS AND METHODS: Sixty consenting men were randomized to receive 11 mL of 2% lignocaine hydrochloride gel (Instillagel, Farco-Pharma GmbH, Cologne, Germany) at 4 degrees C, 22 degrees C or 40 degrees C. The three groups were well matched for age and numbers of previous flexible cystoscopies. The gel was instilled by one operator and the patients were then immediately asked to score the pain on instillation using a 100-mm nongraphical visual analogue scale. RESULTS: Compared with the control group (at 22 degrees C), there was a statistically significant reduction in pain score in the group receiving cold gel (Student's t-test, P<0.05). CONCLUSION: The cooling of 2% lignocaine gel significantly reduced the initial discomfort associated with its delivery into the male urethra before any form of urethral instrumentation.

Administration, Topical↗
PubMed1998

Diabetes mellitus in Egypt: glycaemic control and microvascular and neuropathic complications.

We performed a cross-sectional, population-based survey of persons 20 years of age and older living in Cairo and surrounding rural villages. The purpose was to describe glycaemic control and the prevalence of microvascular and neuropathic complications among Egyptians with diagnosed diabetes, previously undiagnosed diabetes, impaired glucose tolerance, and normal glucose tolerance. A total of 6052 households were surveyed. The response rate was 76% for the household survey and 72% for the medical examination. Among people with previously diagnosed diabetes, mean haemoglobin A1c, was 9.0%. Forty-two per cent had retinopathy, 21% albuminuria, and 22% neuropathy. Legal blindness was prevalent (5%) but clinical nephropathy (7%) and foot ulcers (1%) were uncommon in persons with diagnosed diabetes. Among people with diagnosed diabetes, microvascular and neuropathic complications were associated with hyperglycaemia. Retinopathy was also associated with duration of diabetes; albuminuria with hypertension and hypercholesterolaemia; and neuropathy with age, female sex, and hypercholesterolaemia. Albuminuria was as common in people with previously undiagnosed diabetes (22%) as those with diagnosed disease (21%). Mean haemoglobin A1c was lower (7.8%) and retinopathy (16%) and neuropathy (14%) were less prevalent in people with previously undiagnosed disease. Ocular conditions, blindness, and neuropathy were prevalent in the non-diabetic population. The microvascular and neuropathic complications of diabetes are a major clinical and public health problem in Egypt.

Adult↗
PubMed1998

Utilizing increased response effort to reduce chronic hand mouthing.

The effects of increased response effort on levels of hand mouthing, leisure engagement, and adaptive elbow flexion were investigated with 2 individuals who had been diagnosed with profound disabilities. Arm restraints designed to alter the amount of physical effort necessary to engage in hand mouthing were used. Results indicated that the treatment strategy reduced levels of hand mouthing but produced only small to moderate reductions in levels of leisure engagement and adaptive elbow flexion. At follow-up, the effects of increased response effort on hand mouthing and leisure engagement were maintained for both participants; however, the restraints were associated with substantial reductions in adaptive elbow flexion for 1 participant.

Adaptation, Psychological↗
PubMed1998

Diabetes mellitus and its complications in an African-American community: project DIRECT.

Project DIRECT (Diabetes Intervention Reaching and Educating Communities Together) is a multilevel community-based intervention project designed to address diabetes and its complications in an African-American community. This article presents results of the Project DIRECT pilot study and describes risk factors for diabetes, diabetes prevalence, complications, and care practices. During 1993, a pilot study was conducted among persons 20 to 74 years of age in Wake County, North Carolina. The study involved household interviews and examinations, and more extensive health center interviews and examinations based on the race of the head of the household, previous diagnosis of diabetes, and results of capillary glucose tests done in the household. Of the black population aged 20 to 74 years, 52 +/- 3% reported being inactive and 51 +/- 3% were overweight; the prevalence of diagnosed diabetes was 5.2 +/- 0.9%; the prevalence of undiagnosed diabetes was 5.7 +/- 2.7%; and the prevalence of impaired glucose tolerance was 11.4 +/- 7.5%. Blacks with diabetes were significantly more likely than nonblacks with diabetes to have uncontrolled hypertension and to smoke cigarettes. Blacks with diabetes were significantly less likely to report having health insurance or to have a private health-care provider. Diabetes mellitus is a major public health problem in the African-American community of Wake County. Modifiable risk factors for diabetes and undiagnosed diabetes are common. Project DIRECT is attempting to improve the health-related quality of life of this population by reducing the burden of diabetes and its complications through a multilevel, community-based intervention.

Adult↗
PubMed1998

A project to reduce the burden of diabetes in the African-American Community: Project DIRECT.

Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) is the first comprehensive community diabetes demonstration project in the United States in an African-American community. This article describes its intervention components and evaluation design. The development and implementation of Project DIRECT has included the community since the project's beginning. Interventions are targeted in three areas: health promotion (improving diet and physical activity levels), outreach (improving diabetes awareness, detection of undiagnosed diabetes, and ensuring that persons with diabetes who are not receiving continuing diabetes care are integrated into the health-care system), and diabetes care (improving self-care, increasing access, and improving the quality of diabetes preventive care received within the health-care system). Evaluation will be internal (conducted by Project DIRECT staff to assess process outcomes in persons directly exposed to each specific intervention) and external (review of outcomes to assess the impact of the multi-intervention program at the level of the entire community). Because diabetes exacts a disproportionate toll among African Americans, the findings from this project should aid in developing strategies to lessen the burden of this disorder, particularly among minority populations.

Black or African American↗
PubMed1997

A model for interval-censored tuberculosis outbreak data.

As the incidence of tuberculosis (TB) has increased in the United States, occupationally acquired TB has increased among the health care workers (HCWs). This paper describes a model developed in response to the needs of an outbreak of multidrug-resistant TB. One of the goals of the outbreak investigation was to estimate the risk of tuberculin skin test (TST) conversion as a function of HCW job type and the period during which persons were employed over the study period. TST conversions were evaluated at periodic examinations and data are interval-censored. We present a generalized linear model that extends Efron's survival model for censored survival data to the case of interval-censored data.

Bias↗