Statins and age-related macular degeneration.
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Biomedical subjects
Publications and source records attributed to Gerald McGwin.
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BACKGROUND: Older drivers (licensed drivers aged 60 years and older) have among the highest rates of motor vehicle collision involvement per mile driven of all age groups. Educational programs that promote safe driving strategies among seniors are a popular approach for addressing this problem, but their safety benefit has yet to be demonstrated. The objective of this study was to determine whether an individualized educational program that promoted strategies to enhance driver safety reduces the crash rate of high-risk older drivers. DESIGN/ SETTING: Randomized, controlled, single-masked intervention evaluation at an ophthalmology clinic. PARTICIPANTS: A total of 403 older drivers with visual acuity deficit or slowed visual processing speed or both who were crash-involved in the previous year, drove at least 5 days or 100 miles per week or both, and were at least 60 years old. INTERVENTION: Patients were randomly assigned to usual care (comprehensive eye examination) or usual care plus an individually tailored and administered educational intervention promoting safe-driving strategies. MAIN OUTCOME MEASURE: Police-reported vehicle collision rate, expressed both in terms of person-years of follow-up and person-miles of travel for 2 years postintervention. RESULTS: The intervention group did not differ significantly from the usual care only group in crash rate per 100 person-years of driving (relative risk [RR], 1.08; 95% confidence interval [CI], 0.71-1.64) and per 1 million person-miles of travel (RR, 1.40; 95% CI, 0.92-2.12). The intervention group reported more avoidance of challenging driving maneuvers and self-regulatory behaviors during follow-up than did the usual care only group (p<0.0001). CONCLUSIONS: An educational intervention that promoted safe-driving strategies among visually impaired, high-risk older drivers did not enhance driver safety, although it was associated with increased self-regulation and avoidance of challenging driving situations and decreased driving exposure by self-report.
Recently, there has been an awareness of the variable phenotypic expression of numerous disorders between individuals from different ethnicities, systemic lupus erythematosus (SLE) one of them. These disparities probably arise from the interaction between genetic and non-genetic (environmental, socioeconomic-demographic, cultural and behavioral) factors. To delineate the influence of these factors on SLE outcome, we established a multiethnic (Hispanic, African American and Caucasian) United States (US) early cohort (<5 years disease duration). Ten years later, interesting data have emerged from the LUMINA (Lupus in Minorities: Nature vs. nurture) cohort. For example, African Americans and Hispanics from Texas have a more severe disease than Caucasians and Hispanics from Puerto Rico. Lack of private insurance, acute SLE onset, expression of HLA-DRB1*01 (DR1) and C4A*3 alleles were associated with higher disease activity, whereas age, the number of American College of Rheumatology criteria met, disease activity, corticosteroid use and abnormal illness behaviors were consistent predictors of damage. In turn, damage and poverty were found to predict mortality. We now plan to apply new approaches (genetic admixture) to deconfound the complex interaction between genetic and non-genetic factors influencing SLE outcome. These data may have impact on the development of policies aimed at eliminating health disparities in the US.
PURPOSE: Motor vehicle collisions (MVCs) are the leading cause of maxillofacial fractures. Additionally, maxillofacial injuries are the most common injury related to air bag deployment. We sought to characterize the occupant restraint system (seat belt and air bag) and collision characteristics associated with MVC-related maxillofacial injuries. MATERIALS AND METHODS: The 1991-2000 National (United States) Automotive Sampling System Crashworthiness Data System (CDS) data files were used. The CDS is a national probability sample of passenger vehicles involved in police-reported tow-away MVCs. Analysis was limited to front seat occupants involved in frontal collisions of delta-V (estimated change in velocity) of greater than 15 km/hr. The risk of facial injury was calculated according to occupants' restraint use (unrestrained, seat belt only, air bag only, and seat belt and air bag combined) and compared using risk ratios (RRs) and associated 95% confidence intervals (CIs). RESULTS: Occupants restrained with a seat belt only (RR, 0.48; 95% CI, 0.40 to 0.57) or a seat belt and an air bag (RR, 0.83; 95% CI, 0.73 to 0.94) had a significantly reduced risk of any facial injury compared with completely unrestrained occupants. There was no association for those restrained with an air bag only (RR, 1.19; 95% CI, 0.82 to 1.73). A similar pattern of results was observed for moderate to severe facial injuries and for facial fractures. CONCLUSION: Seat belt use significantly reduces the risk of facial injury in frontal MVCs. Air bag use was not associated with the risk of facial injury.
PURPOSE: We sought to evaluate the frequency and distribution of maxillofacial injuries associated with all-terrain vehicle (ATV) collisions and to compare this with patients involved in motorcycle accidents over the same 5-year period at the University of Alabama at Birmingham. Patients and methods The records of all patients involved in ATV collisions who were admitted to the University of Alabama at Birmingham Trauma Center from January 1998 to January 2003 were reviewed. Age, gender, mechanism of injury, length of stay, Glasgow Coma Scale (GCS) score, maxillofacial injuries, Injury Severity Score (ISS), and maxillofacial Abbreviated Injury Scale (AIS) score were the factors considered for the study. These variables were also analyzed for patients involved in motorcycle collisions who sustained maxillofacial trauma. RESULTS: There were a total of 72 ATV collisions; 23 patients (32%) sustained maxillofacial injuries. The mean age was 31, and there were 59 males (82%) and 13 females (18%). The most common mechanism of injury was an ATV rollover. The warmer seasons and weekend days had the highest frequency of ATV trauma. Of the 23 patients who sustained maxillofacial injuries, the average maxillofacial AIS score was 2. The length of stay and GCS score were 8 days and 12, respectively, compared to 5 days and 15 in the nonmaxillofacial injury group. The most common maxillofacial fracture seen was a zygomaticomaxillary complex fracture (n = 8), followed by mandibular fractures (n = 6), and orbital floor blowout fractures (n = 5). Eighty-three percent of patients with maxillofacial injuries required an operative intervention during their hospitalization. The distribution of maxillofacial fractures in the ATV group was similar to that of an equivalent motorcycle group, but the frequency for the ATV group was higher (32% versus 8%). The length of stay for the motorcycle group was 11 days versus 8 days for the ATV group. The GCS scores, maxillofacial AIS scores, and ISS were similar between the 2 groups (12, 2, and 18, respectively). In patients who sustained maxillofacial fractures, neurologic injuries were the most frequent concomitant injury in the ATV group, whereas orthopedic injuries occurred more often in the motorcycle group. CONCLUSIONS: Maxillofacial injuries are common findings in ATV collisions. ATV patients with maxillofacial fractures have more neurologic impairment at admission and longer hospitalizations than patients sustaining motorcycle injuries. There needs to be an increase in the public health effort to educate individuals about the dangers of ATVs and to provide proper safety guidelines before the purchase of a vehicle.
PURPOSE: To evaluate the efficacy and safety of arteriovenous sheathotomy surgery to decompress branch retinal vein occlusion (BRVO). DESIGN: Prospective, nonrandomized, comparative interventional trial with concurrent control group. PARTICIPANTS: Twenty eyes with decreased visual acuity secondary to BRVO who underwent vitrectomy and surgical decompression by means of arteriovenous sheathotomy were compared with 20 control eyes (10 observation and 10 laser treated). INTERVENTION: The 20 surgical eyes underwent pars plana vitrectomy and arteriovenous sheathotomy with a microvitreoretinal blade. Of the 20 control eyes, 10 had no intervention (observation), and 10 had grid laser photocoagulation a mean of 9 months after diagnosis. RESULTS: The mean preoperative visual acuity was 20/250 in the surgical group and 20/180 in the control group (statistically similar in the observation group and laser-treated group). The mean 14-month visual acuity was 20/63 in the surgical group and 20/125 in the control group (P = 0.02). Seventy-five percent of the surgical group halved their visual angle compared with 40% of the control group (40% observation vs. 40% laser; P = 0.025). Average lines of visual acuity gained were 4.55 in the surgical group and 1.55 in the control group (P = 0.0226; 1.1 lines in observation group and 2.0 lines in laser group). CONCLUSIONS: Surgical arteriovenous sheathotomy to decompress BRVO results in significantly better visual outcomes than a matched control group of observation and laser-treated eyes. A randomized multicenter clinical trial is warranted to determine the efficacy of this procedure.
PURPOSE: To determine if hypothyroidism is associated with an increased risk of glaucoma using a large cohort of patients. DESIGN: Nested case-control study. PARTICIPANTS: Patients seen at the Veterans Affairs Medical Center in Birmingham, Alabama with newly diagnosed glaucoma between 1997 and 2001 were selected (n = 590) and age-matched to nonglaucoma controls (n = 5897). METHODS: Patient information was extracted from the Birmingham Veterans Affairs Medical Center data files containing demographic, clinical, and medication information. An index date was assigned to the glaucoma subjects corresponding to the time of diagnosis. Patients who had a glaucoma diagnosis before the observation period of the study were excluded. Ten controls were randomly selected for each patient and matched on age (+/-1 year) and an encounter on or before the index date of the matched case. MAIN OUTCOME MEASURES: Odds ratios (ORs) for the association between the prior diagnosis of hypothyroidism and the risk of developing glaucoma with adjustment for the presence of diabetes, lipid metabolism disorders, hypertension, cardiovascular disease, cerebrovascular disease, arterial disease, and migraines. RESULTS: After adjustment for the other potential risk factors, patients were significantly more likely to have prior hypothyroidism than controls (OR, 1.40; 95% confidence interval, 1.01-1.97). CONCLUSIONS: Our study has demonstrated a significantly greater risk of subjects with a preexisting diagnosis of hypothyroidism developing glaucoma, compared with controls, in a large Veterans Affairs Medical Center population.
PURPOSE: To examine the impact of depression in older adults on responses to the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) independent of demographics, vision, and general health. DESIGN: Cross-sectional. PARTICIPANTS: We took the opportunity of an ongoing study on older drivers to address the specific aim stated above. The recruitment population consisted of 6342 older adults (> or =60 years) who were licensed drivers residing in Birmingham, Alabama; who had been involved in a crash in the prior year, as identified by Alabama Department of Public Safety records; and whose phone numbers could be located. Additional eligibility criteria were visual acuity impairment, slowed visual processing speed, or both, and a Mini-Mental State Examination score of > or =23. Persons in the recruitment population who met these eligibility criteria and agreed to enroll in a study on driver safety (purpose of the main study) numbered 403. METHODS: The following questionnaires were interviewer administered in person and scored per standard procedures: the NEI VFQ-25, the Center for Epidemiological Studies Depression Scale (CES-D), a general health questionnaire, and a review of demographic information. Depressed persons were defined as those with CES-D scores of > or =16. There were complete data on 397 persons. MAIN OUTCOME MEASURE: Reduced score on the NEI VFQ-25 (defined by a score of <87.5) on the total questionnaire and 12 subscales. RESULTS: After adjusting for demographics, vision, mental status, and general health, depression was significantly associated with a reduced NEI VFQ-25 score for total score and the subscales of distance vision, peripheral vision, role difficulties, dependencies, and mental health. Odds ratio point estimates in these adjusted associations ranged from 2.9 to 4.6. CONCLUSIONS: The results imply that older persons who are depressed may have reduced scores on the NEI VFQ-25 independent of the impact of vision problems. Depression in the elderly could be influencing their self-perception of the burden of eye disease and treatment effectiveness in clinical and epidemiologic studies.
This study compared data from death certificates (DC), medical examiner (ME) reports, and Uniform Crime Reporting (UCR) Program for homicides among children age 5 years or younger in Jefferson County, Alabama between 1988 and 1998. Records from each source were matched independently to records from the other two sources. Kappa coefficients measured the chance-corrected agreement between sources. The strongest correlations were for victim's gender and race. Correlations were weakest for victim's relationship to the offender and offender's gender. DC and ME data demonstrated excellent agreement and provided a comprehensive count of homicides in Jefferson County, whereas UCR comparisons had lower correlations. However, the UCR is a valuable source of child homicide data in the United States that is underutilized in public health research.
PURPOSE: The purpose of this project is to evaluate the association of vision limitation and function among a population of older and younger adults. METHODS: The effects of self-reported serious difficulty with vision and legal blindness were evaluated on six activities of daily living (ADLs) and six instrumental activities of daily living (IADLs). Subjects were 67,570 adults over the age of 18 who participated in the 1995 National Health Interview Survey on Disability. RESULTS: Serious difficulty with vision (SDV) and legal blindness (LB) were independently associated with increased odds of poorer function for each of the ADLs and IADLs. In stratified analysis, the effect of vision on function was modified by age. Both SDV and LB produced a greater impact on performance of ADLs and IADLs among younger rather than older subjects. CONCLUSIONS: Vision had an impact on all ADLs and IADLs evaluated, with greater impact on self-reported function for younger adults. This suggests that younger adults perceive limitations associated with visual disability differently than do older adults.
Proposed mechanisms by which sudden unexplained death syndrome in epilepsy (SUDEP) occurs include cardiac dysrhythmias. We hypothesized that individuals dying of SUDEP would have enlarged hearts compared with normal, increasing the risk of sudden cardiac death should the autonomic nervous system initiate a dysrhythmia. We performed a retrospective case-control study in a medical examiner population, comparing the mean heart mass in a group of individuals who died of SUDEP to a group of individuals with epilepsy who died suddenly due to some unrelated cause (non-SUDEP). We found no significant difference in the mean heart mass between the 2 groups when analyzing the unadjusted data. Upon stratifying the cases by age, however, we found a significant reduction in the frequency of SUDEP in individuals 40 or more years of age with an increased heart mass compared with those younger. This reduced frequency disappeared when cases where the cause of death was indeterminate between SUDEP and heart disease were reclassified from non-SUDEP to SUDEP. With increasing age, the likelihood of finding a cause of death that competes with the possibility of SUDEP increases, making SUDEP appear to be a phenomenon of the young. The inclusion of seizure deaths evaluated in a medical examiner office in studies of SUDEP would provide the benefit of a more certain diagnosis in each given case. Moreover, the inclusion of cases from the medical examiner population would stem attrition in a clinical study due to loss to follow-up.
OBJECTIVE: The purpose of this study was to evaluate the association between motorcycle licensing and operation regulations and motorcycle mortality rates in the United States during 1997 through 1999. METHODS: A population-based ecologic study was used. RESULTS: Lower mortality rates were observed in states with the following motorcycling requirements: skill test for a motorcycle permit (rate ratio [RR], 0.76; 95% confidence interval [CI], 0.69-0.84), driver training (RR, 0.80; 95% CI, 0.74-0.86), longer duration of learner's permits (95-190 days [RR, 0.86; 95% CI, 0.79-0.95] and >190 days [RR, 0.87; 95% CI, 0.81-0.93], three or more learner's permit restrictions (RR, 0.78; 95% CI, 0.73-0.84), and a full helmet law (RR, 0.76; 95% CI, 0.71-0.81). CONCLUSION: Specific motorcycle licensure policies appear to be associated with lower mortality rates.
BACKGROUND: Head injury is a significant cause of both morbidity and mortality. Motor vehicle collisions (MVCs) are the most common source of head injury in the United States. No studies have conclusively determined the applicability of computer models for accurate prediction of head injuries sustained in actual MVCs. This study sought to determine the applicability of such models for predicting head injuries sustained by MVC occupants. METHODS: The Crash Injury Research and Engineering Network (CIREN) database was queried for restrained drivers who sustained a head injury. These collisions were modeled using occupant dynamic modeling (MADYMO) software, and head injury scores were generated. The computer-generated head injury scores then were evaluated with respect to the actual head injuries sustained by the occupants to determine the applicability of MADYMO computer modeling for predicting head injury. RESULTS: Five occupants meeting the selection criteria for the study were selected from the CIREN database. The head injury scores generated by MADYMO were lower than expected given the actual injuries sustained. In only one case did the computer analysis predict a head injury of a severity similar to that actually sustained by the occupant. CONCLUSION: Although computer modeling accurately simulates experimental crash tests, it may not be applicable for predicting head injury in actual MVCs. Many complicating factors surrounding actual MVCs make accurate computer modeling difficult. Future modeling efforts should consider variables such as age of the occupant and should account for a wider variety of crash scenarios.
BACKGROUND: Among older trauma patients, those with preexisting chronic medical conditions (CMCs) appear to have an elevated risk of death. Whether this association is dependent on the severity of injury or other occult factors remains unanswered. This study evaluated the association between preexisting CMCs and risk of death among older trauma patients according to injury severity. METHODS: This was a retrospective cohort study using data from the National Trauma Data Bank, a registry of trauma patients admitted to 131 trauma centers across the United States. The main outcome measure was in-hospital mortality. RESULTS: In patients 50 to 64 years of age who sustain severe (Injury Severity Score [ISS] of 26+) and moderate injuries (ISS of 16-25), the presence of one or more CMCs is not associated with an increased relative risk (RR) of death (RR, 0.80 and 95% confidence interval [CI], 0.71-0.90; RR, 1.09 and 95% CI, 0.95-1.24, respectively). Those with minor injuries (ISS < 16) have increased risk of death (RR, 2.80; 95% CI, 2.33-3.36). For those patients 65 years of age and older who sustain severe, moderate, and minor injuries, the pattern of results is similar (RR, 0.91 and 95% CI, 0.83-1.00; RR, 1.13 and 95% CI, 1.04-1.23; and RR, 1.88 and 95% CI, 1.73-2.05, respectively). CONCLUSION: Older trauma patients with CMCs who present with minor injuries should be considered to have an increased risk of death when compared with their nonchronically ill counterparts.
BACKGROUND: Seat belts and air bags have been shown to significantly reduce morbidity and mortality following MVCs. Research suggests that restraint use does not protect against lower extremity fracture; however, no population-based studies of this association exist. The purpose of this study is to compare the effectiveness of combined seat belt and airbag restraint systems with airbag alone, seat belt alone, and no restraints with respect to incidence and location of lower extremity fractures. METHODS: A retrospective analysis of front seat occupants involved in police-reported, tow-away frontal MVCs was conducted using data from the 1995 through 2000 National Automotive Sampling System (NASS). Incidence and relative risk (RR) of fracture to specific bony regions were measured according to seat belt use and airbag deployment. RESULTS: Compared with unrestrained occupants, occupants restrained with airbag only had significantly higher risk for all types of lower extremity fractures whereas those occupants restrained with either seat belt only or seat belt and airbag had lower risk of fracture. The greatest difference was seen with tibia/fibula fractures in airbag only (RR, 2.14) but this trend continued to be significant with femur and pelvic fractures (RR, 1.13 and 1.23, respectively). CONCLUSION: While airbags may reduce the risk of death when used alone or in combination with seat belts, the results of this study demonstrate that air bags increase the risk of lower extremity fractures when used as the sole method of passenger protection. Also, they may do so differentially according to skeletal region. This data strongly support the consideration of developing accessory knee bolster airbags to prevent the "submarining" or sliding under the airbag that may be responsible for this finding.
BACKGROUND: Blunt cerebrovascular artery injury (BCI) remains difficult to diagnose but is recognized with increasing frequency after motor vehicle collisions (MVCs). Failure to detect this injury in a timely fashion can be devastating. Criteria that can be used to heighten the suspicion of this injury have been suggested; however, more encompassing screening has been recommended. To address this need, we sought to describe occupant, vehicle, and collision characteristics among MVC occupants who sustained a BCI. METHODS: All cases of BCI identified in the National Automotive Sampling System Crashworthiness Data System, a national probability sample of passenger vehicles involved in police-reported tow-away MVCs, between 1993 and 2001 were selected. Information on occupant (e.g., demographics, seating position, and restraint use), collision (e.g., collision type and severity), and vehicle characteristics were obtained and summarized using descriptive statistics. RESULTS: Nine-hundred forty individuals with BCI were identified in the Crashworthiness Data System data files. Over half were belted (57.4%) and 82.3% had airbag deployment; 16.2% were partially or completely ejected from the vehicle. Head and thoracic injuries were common (44.4% and 40.8%, respectively); 27.8% sustained a cervical spine fracture and 21.0% sustained a soft-tissue injury to the neck. The mean Injury Severity Score was 33.6. The case fatality rate was 44.5%. The majority of BCI occupants were drivers (76.0%). Among belted occupants, the lap/shoulder was the most commonly attributed as the injury source (61.4%). Among unbelted occupants, frequent injury sources included air bags (15.0%), windshield (13.7%), and other interior objects. With respect to collision characteristics, the average change in velocity (Delta V) was 43.3 km/h. The majority of collisions were frontal (76.2%). CONCLUSION: This study indicates that BCI is both a rare and lethal injury typified by specific occupant and collision characteristics. These characteristics provide insight as to the cause of this injury that may aid in the evaluation and management of the blunt trauma patient at risk for BCI.
BACKGROUND: Chest computed tomography (CT) is an excellent screening tool for blunt aortic injuries (BAIs). Aortography is considered the "gold standard" for diagnosis. Recent evidence suggests that new-generation, multislice, helical CT technology can accurately diagnose BAI. METHODS: A retrospective review of aortograms performed to evaluate for BAI was compared with the results of CT and operative findings. BAIs definitively diagnosed by CT alone were also studied. RESULTS: Between July 1, 1996, and June 30, 2002, 113 aortograms were obtained, with 28 BAI cases confirmed. Of these, 27 were congruently diagnosed by CT. Only one computed tomographic scan diagnostic for BAI had a subsequent negative aortogram. Seventeen BAIs were diagnosed with CT alone. Ten were confirmed operatively and seven were treated nonoperatively because of age, comorbid conditions, severity of injury, or the presence of small intimal defects. CONCLUSION: CT technology has evolved to allow for the definitive diagnosis and treatment of BAI. Aortography should still be used where new-generation CT is not available.
BACKGROUND: Side airbags (SABs) were developed as an energy-absorbing barrier to protect specific occupant body regions in near side impact motor vehicle collisions. METHODS: The National Automotive Sampling System Crashworthiness Data System was used to evaluate drivers and front-seated passengers in 1998 or newer vehicles involved in near side impact collisions. Risk ratios were calculated comparing the risk of head and thoracic injury among occupants in vehicles with and without SABs adjusting for occupant, vehicle, and collision characteristics. RESULTS: Occupants in vehicles equipped with head protection SABs had a 75% lower risk of head injury (p = 0.008) after near side collisions. With respect to thoracic injury, SABs that provide thoracic protection are associated with a 68% reduction (p = 0.01) in thoracic injury risk. CONCLUSION: As SAB-equipped vehicles become an increasingly larger segment of the on-road vehicle fleet, the impact of head and thoracic injury after near side impact collision is likely to be reduced.