Biomedical subjects

Mina Torres

Publications and source records attributed to Mina Torres.

8 recordsLinked to original sources

PubMed2006

Effect of peroxisome proliferator-activated receptor gamma agonist treatment on subclinical atherosclerosis in patients with insulin-requiring type 2 diabetes.

OBJECTIVE: To determine the effect of thiazolidinedione treatment on subclinical atherosclerosis progression in insulin-requiring patients with clinical characteristics suggesting type 2 diabetes. RESEARCH DESIGN AND METHODS: Eligible participants (n = 299) were randomized within strata of baseline common carotid artery (CCA) intima-media thickness (IMT) (<0.8 mm, >or=0.8 mm) to 400 mg troglitazone daily or placebo for 2 years. A general linear mixed-effects model was used to compare the rate of change in CCA-IMT between treatment groups. RESULTS: Overall, average rates of CCA-IMT change were not significantly different between troglitazone- and placebo-treated subjects (0.0030 +/- 0.021 vs. 0.0066 +/- 0.021 mm/year; P = 0.17). In the stratum of subjects with CCA-IMT >or=0.8 mm, troglitazone significantly reduced the progression of CCA-IMT relative to placebo (0.0013 +/- 0.022 vs. 0.0084 +/- 0.023 mm/year; P = 0.03). Fasting glucose, insulin, and HbA(1c) were significantly lower in troglitazone- versus placebo-treated subjects (P < 0.01). Whereas blood pressure significantly differed between treatment groups in the >or=0.8-mm stratum, there was no difference between treatment groups in the <0.8-mm stratum. CONCLUSIONS: Insulin sensitization and reduction in blood pressure may be contributory mechanisms by which troglitazone reduced subclinical atherosclerosis progression in this cohort of well-controlled insulin-dependent patients with clinical characteristics suggesting type 2 diabetes.

Adult↗

PubMed2005

Self-reported comorbidities and visual function in a population-based study: the Los Angeles Latino Eye Study.

OBJECTIVE: To assess the association of self-reported systemic and ocular comorbid disease and visual function in Latino subjects. METHODS: National Eye Institute 25-item Visual Function Questionnaire (NEI-VFQ-25) and eye examination data were obtained from 5380 participants in the Los Angeles Latino Eye Study, a population-based prevalence study of eye disease in Latino subjects 40 years and older. We developed and contrasted 5 comorbidity measures. One-way analysis of variance was used to assess the association between comorbidity and visual impairment and self-reported visual function. Regression analyses determined the association of sociodemographic variables, clinical variables, and the best measure of comorbidity with the NEI-VFQ-25 composite score. The main outcome measure was self-reported visual function as assessed by the NEI-VFQ-25 composite score. RESULTS: On average, visual function subscale scores were lowest for those participants with the most systemic comorbid conditions (P<.05). This was more evident in participants with moderate or severe visual impairment compared with those with mild or no visual impairment (P<.05). CONCLUSIONS: Self-reported systemic comorbidities were associated with self-reported visual function. This association was greater at more severe levels of visual impairment. Of the 5 comorbidity measures assessed, the measure that summed the number of self-reported systemic comorbidities correlated most with self-reported visual function.

Adult↗

PubMed2005

Refractive error, ocular biometry, and lens opalescence in an adult population: the Los Angeles Latino Eye Study.

PURPOSE: To characterize age- and gender-related differences in refractive error, ocular biometry, and lens opalescence (NOP) in a population-based sample of adult Latinos. Also assessed were the determinants of age-related refractive differences. METHODS: Participants in the Los Angeles Latino Eye Study (LALES), a population-based study of Latinos aged 40 years and more, underwent an ophthalmic examination, including ultrasonic measurements of axial length (AL), vitreous chamber depth (VCD), anterior chamber depth (ACD), lens thickness (LT), and noncycloplegic automated and subjective refraction. Corneal curvature/power (CP) was measured using an autorefractor. NOP was graded at the slit lamp by an ophthalmologist using the Lens Opacity Classification System II. Age- and gender-related differences were calculated. Multiple regression models were used to identify the determinants of age-related refractive differences. RESULTS: Of the 6357 LALES participants, 5588 phakic individuals with biometric data were included in this analysis. Older individuals had shallower ACDs, thicker lenses, more NOP, and more hyperopia compared to younger individuals (P < 0.001). There was no age-related difference in AL (P > or = 0.05). Women had significantly shorter AL, shallower ACD and VCD, than did men (P < or = 0.01). The strongest determinants of refractive error were AL (primarily VCD) and CP. NOP was a small but significant determinant of refractive error in older individuals. CONCLUSIONS: Age- and gender-related differences in ocular biometric, refractive error, and NOP measurements are present in adult Latinos. While the relative contribution of NOP in determining refractive error is small, it is greater in older persons compared to younger individuals.

Adult↗

PubMed2004

Prevalence of lens opacities in Latinos: the Los Angeles Latino Eye Study.

OBJECTIVE: To estimate the age- and gender-specific prevalence of posterior subcapsular (PSC), nuclear, cortical, and mixed lens opacities in a population-based sample of Latinos 40 years and older. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in Los Angeles, California. METHODS: A population-based sample of Latinos underwent a complete eye examination, including assessment of presence and severity of lens opacification, using the slit lamp-based Lens Opacities Classification System II (LOCS II). All lens changes (including pseudophakia/aphakia); any nuclear, PSC, and cortical opacities; and nuclear-only, PSC-only, and cortical-only opacities were evaluated. Frequency distributions and chi-square test analyses were used to determine the age- and gender-specific prevalences for each opacity type. MAIN OUTCOME MEASURES: Prevalences of cortical, nuclear, and posterior subcapsular opacities. RESULTS: Of the 7789 eligible subjects, 6357 completed a clinical examination (82% participation rate). Of all participants with LOCS II grading, 20% had all lens changes, 7.6% had cortical-only opacities, 3.5% had nuclear-only opacities, 0.4% had PSC-only opacities, and 5.9% had mixed-type opacities. The prevalence of all types of lens opacities increased with age (P<0.0001). Of all participants with mixed opacities, 49% had monocular visual impairment and 20% had binocular impairment. Of all 6357 participants, 3.9% had undergone cataract extraction in at least one eye. CONCLUSION: Our data provide the first population-based estimates of the prevalence and severity of lens opacities in Latinos. Cortical opacities were the most common type. The high rate of visual impairment from lens opacities suggests that programs that increase access to cataract surgery for older Latinos could help to reduce the burden of visual impairment in the United States.

Adult↗

PubMed2004

The Los Angeles Latino Eye Study: design, methods, and baseline data.

OBJECTIVE: To describe the study design, operational strategies, procedures, and baseline characteristics of the Los Angeles Latino Eye Study (LALES), a population-based assessment of the prevalence of visual impairment, ocular disease, and visual functioning in Latinos. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in Los Angeles, California. METHODS: A detailed interview and eye examination were performed on each eligible participant. The interview included an assessment of demographic, behavioral, and ocular risk factors and health-related and vision-related quality of life. The eye examination included a measurement of visual acuity, intraocular pressure, and visual fields; fundus and optic disc photography; a detailed anterior and posterior segment examination; and measurement of blood pressure, glycosylated hemoglobin levels, and blood glucose levels. MAIN OUTCOME MEASURES: Prevalence of visual impairment, blindness, cataract, glaucoma, diabetic retinopathy, and age-related macular degeneration constitute the study's primary outcome variables. Secondary outcomes include odds ratios for risk factors associated with eye disease, health-related quality of life, and vision-related quality of life. Response rates and baseline characteristics are presented. RESULTS: Of the 7789 individuals eligible for LALES, 6357 (82%) had a clinical examination; an additional 524 completed only an in-home interview. The majority of participants were female (58%), the average (+/- standard deviation) age was 54.9 (+/-10.8) years, and 80.0% were of Mexican origin and 0.4% self-identified as American Indian or Alaskan Native. The age distribution of LALES participants was similar to that of Latinos of Mexican origin in the rest of the United States. CONCLUSION: The LALES has recruited Latinos 40 and older for an ophthalmic epidemiologic study. The LALES cohort will provide information about the prevalence and risk factors of ocular disease in the largest and fastest growing minority in the United States.

Adult↗

PubMed2004

Prevalence of diabetic retinopathy in adult Latinos: the Los Angeles Latino eye study.

OBJECTIVE: To estimate age- and gender-specific prevalence of diabetic retinopathy (DR) and to determine the association of type, duration, and treatment of diabetes with the prevalence of DR in adult Latinos. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Six thousand three hundred fifty-seven Latinos aged 40 years and older from 6 census tracts in Los Angeles, California. METHODS: The study cohort consisted of all self-identified Latinos of primarily Mexican ancestry aged 40 years and older residing in 6 census tracts in La Puente, Los Angeles County, California. All participants diagnosed with diabetes underwent a complete ophthalmologic examination, including stereoscopic fundus photography (7 standard Early Treatment Diabetic Retinopathy Study fields). Photographs were graded in a masked manner using a modified Airlie House Grading System to assess presence and severity of DR. MAIN OUTCOME MEASURES: Prevalence of nonproliferative DR, proliferative DR, and macular edema. RESULTS: Of 1263 participants with definite diabetes mellitus, gradable fundus photographs were available in 1217 participants (96%). Of those 1217 participants, 46.9% had DR. Severe nonproliferative DR and proliferative DR were present in 4.4% and 6.1% of diabetics, respectively. Macular edema was observed in 10.4% and clinically significant macular edema was observed in 6.2% of all diabetics. No age- or gender-related differences were present. After adjusting for duration of diabetes, the prevalence of DR was similar in persons with type 1 and type 2 diabetes. CONCLUSIONS: Our data suggest that the prevalence of DR is high among Latinos of primarily Mexican ancestry. The increase in prevalence of DR with longer duration of diabetes emphasizes the public health importance of early diagnosis and management in Latinos. Further data on incidence and progression are required to understand better the natural history of DR in Latinos.

Adult↗

PubMed2003

Hormone therapy and the progression of coronary-artery atherosclerosis in postmenopausal women.

BACKGROUND: In postmenopausal women with coronary artery disease, conjugated equine estrogen with or without continuous administration of medroxyprogesterone acetate has failed to slow the progression of atherosclerosis. Whether 17beta-estradiol (the endogenous estrogen molecule) alone or administered sequentially with medroxyprogesterone acetate can slow the progression of atherosclerosis is unknown. METHODS: We conducted a double-blind, placebo-controlled trial in 226 postmenopausal women (mean age, 63.5 years) who had at least one coronary-artery lesion. Participants were randomly assigned to usual care (control group), estrogen therapy with micronized 17beta-estradiol alone (estrogen group), or 17beta-estradiol plus sequentially administered medroxyprogesterone acetate (estrogen-progestin group). In all patients the low-density lipoprotein (LDL) cholesterol level was reduced to a target of less than 130 mg per deciliter. The primary outcome was the average per-participant change between base-line and follow-up coronary angiograms in the percent stenosis measured by quantitative coronary angiography. RESULTS: After a median of 3.3 years of follow-up, the mean (+/-SE) change in the percent stenosis in the 169 participants who had a pair of matched angiograms was 1.89+/-0.78 percentage points in the control group, 2.18+/-0.76 in the estrogen group, and 1.24+/-0.80 in the estrogen-progestin group (P=0.66 for the comparison among the three groups). The mean difference in the percent stenosis between the estrogen group and the control group was 0.29 percentage point (95 percent confidence interval, -1.88 to 2.46), and the mean difference between the estrogen-progestin group and the control group was -0.65 (95 percent confidence interval, -2.87 to 1.57). CONCLUSIONS: In older postmenopausal women with established coronary-artery atherosclerosis, 17beta-estradiol either alone or with sequentially administered medroxyprogesterone acetate had no significant effect on the progression of atherosclerosis.

Coronary Angiography↗

PubMed2003

Time from diagnosis of type 2 diabetes to initiation of insulin therapy is related to carotid artery intima-media thickness.

To investigate the association between time from diagnosis of type 2 diabetes to initiation of insulin therapy (pre-exogenous insulin period) and intima-media thickness (IMT) of the common carotid artery (CCA), a cross-sectional analysis was conducted among 98 males and 193 females (90% Hispanic) with type 2 diabetes, aged 30-70 years old. The association between the pre-exogenous insulin period and the primary outcome was examined in men and women using analysis of covariance (ANCOVA) with adjustment for current age, duration of insulin therapy, low-density lipoprotein (LDL) cholesterol, systolic blood pressure and hemoglobin A1c. The pre-exogenous insulin period was significantly and linearly associated with mean IMT of the CCA in men. In women, the linear trend was not significant while a significant quadratic trend was noted across three categories of the pre-exogenous insulin period (0-5, 6-10, 11-24 years). Longitudinal data are needed to determine the effect of early initiation of insulin therapy on the progression of subclinical atherosclerosis among persons with diabetes.

Adult↗