The power of TOPMed imputation for the discovery of Latino-enriched rare variants associated with type 2 diabetes.

AIMS/HYPOTHESIS: The Latino population has been systematically underrepresented in large-scale genetic analyses, and previous studies have relied on the imputation of ungenotyped variants based on the 1000 Genomes (1000G) imputation panel, which results in suboptimal capture of low-frequency or Latino-enriched variants. The National Heart, Lung, and Blood Institute (NHLBI) Trans-Omics for Precision Medicine (TOPMed) released the largest multi-ancestry genotype reference panel representing a unique opportunity to analyse rare genetic variations in the Latino population. We hypothesise that a more comprehensive analysis of low/rare variation using the TOPMed panel would improve our knowledge of the genetics of type 2 diabetes in the Latino population. METHODS: We evaluated the TOPMed imputation performance using genotyping array and whole-exome sequence data in six Latino cohorts. To evaluate the ability of TOPMed imputation to increase the number of identified loci, we performed a Latino type 2 diabetes genome-wide association study (GWAS) meta-analysis in 8150 individuals with type 2 diabetes and 10,735 control individuals and replicated the results in six additional cohorts including whole-genome sequence data from the All of Us cohort. RESULTS: Compared with imputation with 1000G, the TOPMed panel improved the identification of rare and low-frequency variants. We identified 26 genome-wide significant signals including a novel variant (minor allele frequency 1.7%; OR 1.37, p=3.4 × 10-9). A Latino-tailored polygenic score constructed from our data and GWAS data from East Asian and European populations improved the prediction accuracy in a Latino target dataset, explaining up to 7.6% of the type 2 diabetes risk variance. CONCLUSIONS/INTERPRETATION: Our results demonstrate the utility of TOPMed imputation for identifying low-frequency variants in understudied populations, leading to the discovery of novel disease associations and the improvement of polygenic scores. DATA AVAILABILITY: Full summary statistics are available through the Common Metabolic Diseases Knowledge Portal ( https://t2d.hugeamp.org/downloads.html ) and through the GWAS catalog ( https://www.ebi.ac.uk/gwas/ , accession ID: GCST90255648). Polygenic score (PS) weights for each ancestry are available via the PGS catalog ( https://www.pgscatalog.org , publication ID: PGP000445, scores IDs: PGS003443, PGS003444 and PGS003445).

Genome-wide association study of colorectal cancer in Hispanics.

Genome-wide association studies (GWAS) have identified 58 susceptibility alleles across 37 regions associated with the risk of colorectal cancer (CRC) with P < 5×10(-8) Most studies have been conducted in non-Hispanic whites and East Asians; however, the generalizability of these findings and the potential for ethnic-specific risk variation in Hispanic and Latino (HL) individuals have been largely understudied. We describe the first GWAS of common genetic variation contributing to CRC risk in HL (1611 CRC cases and 4330 controls). We also examine known susceptibility alleles and implement imputation-based fine-mapping to identify potential ethnicity-specific association signals in known risk regions. We discovered 17 variants across 4 independent regions that merit further investigation due to suggestive CRC associations (P < 1×10(-6)) at 1p34.3 (rs7528276; Odds Ratio (OR) = 1.86 [95% confidence interval (CI): 1.47-2.36); P = 2.5×10(-7)], 2q23.3 (rs1367374; OR = 1.37 (95% CI: 1.21-1.55); P = 4.0×10(-7)), 14q24.2 (rs143046984; OR = 1.65 (95% CI: 1.36-2.01); P = 4.1×10(-7)) and 16q12.2 [rs142319636; OR = 1.69 (95% CI: 1.37-2.08); P=7.8×10(-7)]. Among the 57 previously published CRC susceptibility alleles with minor allele frequency ≥1%, 76.5% of SNPs had a consistent direction of effect and 19 (33.3%) were nominally statistically significant (P < 0.05). Further, rs185423955 and rs60892987 were identified as novel secondary susceptibility variants at 3q26.2 (P = 5.3×10(-5)) and 11q12.2 (P = 6.8×10(-5)), respectively. Our findings demonstrate the importance of fine mapping in HL. These results are informative for variant prioritization in functional studies and future risk prediction modeling in minority populations.

Incidence of type 2 diabetes in Mexico: results of the Mexico City Diabetes Study after 18 years of follow-up.

OBJECTIVE: To estimate the incidence of type 2 diabetes (T2D) in Mexican population. MATERIALS AND METHODS: Population based prospective study. At baseline (1990), the population at risk (1939 non-diabetic adults 35-64 years) was evaluated with oral glucose tolerance test. Subsequent similar evaluations were done (1994, 1998, 2008). American Diabetes Association diagnostic criteria were applied. RESULTS: The period of observation was 27842 person-years, the cumulative incidence of T2D was 14.4 and 13.7 per 1000 person-years for men and women, respectively. Incidence was 15.8, 15.7 and 12.7 per 1 000 person-years for the second (1994), third (1998) and fourth (2008) follow-up phases, respectively. The mean age at diagnosis was 44 years for prevalent cases and 56 years for incident cases. CONCLUSIONS: This is the first estimate of long-term incidence of T2D in Mexican population. The incidence is among the highest reported worldwide. It remained with few changes throughout the study period.

Risk factors associated to diabetes in Mexican population and phenotype of the individuals who will convert to diabetes.

OBJECTIVE: To describe risk factors associated to the incidence of type 2 diabetes (T2D) in Mexican population and to define phenotypic (clinical, anthropometric, metabolic) characteristics present in the individual who will convert to diabetes, regardless of time of onset. MATERIALS AND METHODS: The Mexico City Diabetes Study began in 1990, with 2 282 participants, and had three subsequent phases: 1994, 1998, and 2008. A systematic evaluation with an oral glucose tolerance test was performed in each phase. For diagnosis of T2D, American Diabetes Association criteria were used. RESULTS: The population at risk was 1939 individuals. Subjects who were in the converter stage (initially non diabetic that eventually converted to T2D) had, at baseline, higher BMI (30 vs 27), systolic blood pressure (119 vs 116 mmHg), fasting glucose (90 vs 82mg/dl), triglycerides (239 vs 196mg/dl), and cholesterol (192 vs 190mg/dl), compared with subjects who remained non converters (p<0.05). CONCLUSION: The phenotype described represents a potentially identifiable phase and a target for preventive intervention.

Exome Sequencing Data Analysis and a Case-Control Study in Mexican Population Reveals Lipid Trait Associations of New and Known Genetic Variants in Dyslipidemia-Associated Loci.

Background: Plasma lipid levels are a major risk factor for cardiovascular diseases. Although international efforts have identified a group of loci associated with the risk of dyslipidemia, Latin American populations have been underrepresented in these studies. Objective: To know the genetic variation occurring in lipid-related loci in the Mexican population and its association with dyslipidemia. Methods: We searched for single-nucleotide variants in 177 lipid candidate genes using previously published exome sequencing data from 2838 Mexican individuals belonging to three different cohorts. With the extracted variants, we performed a case-control study. Logistic regression and quantitative trait analyses were implemented in PLINK software. We used an LD pruning using a 50-kb sliding window size, a 5-kb window step size and a r2 threshold of 0.1. Results: Among the 34251 biallelic variants identified in our sample population, 33% showed low frequency. For case-control study, we selected 2521 variants based on a minor allele frequency ≥1% in all datasets. We found 19 variants in 9 genes significantly associated with at least one lipid trait, with the most significant associations found in the APOA1/C3/A4/A5-ZPR1-BUD13 gene cluster on chromosome 11. Notably, all 11 variants associated with hypertriglyceridemia were within this cluster; whereas variants associated with hypercholesterolemia were located at chromosome 2 and 19, and for low high density lipoprotein cholesterol were in chromosomes 9, 11, and 19. No significant associated variants were found for low density lipoprotein. We found several novel variants associated with different lipemic traits: rs3825041 in BUD13 with hypertriglyceridemia, rs7252453 in CILP2 with decreased risk to hypercholesterolemia and rs11076176 in CETP with increased risk to low high density lipoprotein cholesterol. Conclusions: We identified novel variants in lipid-regulation candidate genes in the Mexican population, an underrepresented population in genomic studies, demonstrating the necessity of more genomic studies on multi-ethnic populations to gain a deeper understanding of the genetic structure of the lipemic traits.

The status of diabetes care in Mexican population: are we making a difference? Results of the National Health and Nutrition Survey 2006.

OBJECTIVE: Examine clinical indicators to evaluate diabetes care in Mexico. MATERIAL AND METHODS: Diabetics (self reported, with therapy) were examined with standardized questionnaires, anthropometry, glucose, lipids and glycohemoglobin. Data were analyzed statistically. RESULTS: There were 2 644 patients, 677 cases without access to medical care (73% women), most lived in rural communities and spoke aboriginal dialect. Prevalence of obesity for private access group was 21.2%, for other or non access group was between 31 and 65%. The group without or basic education was most common, 76% of the cases had HDL <40 mg/dl and 36% had hypertriglyceridemia. Only 6.6% of patients had HbA1c <7%. There was no significant difference between HbA1c values observed in the group with or without access. Most patients were treated with oral agents. A significant group was without therapy. Assessments for complications was infrequent. CONCLUSIONS: Current model for diabetes care in Mexico is inefficacious and a paradigm change is necessary.

Applicability of Framingham risk equations for studying a low-income Mexican population.

OBJECTIVE: To compare the predicted risk of coronary heart disease (CHD) and incident myocardial infarction (MI) using Framingham score equations with the observed rate of MI in Mexican subjects. MATERIAL AND METHODS: Longitudinal study that included 1 667 men and women aged 35 to 64 years without MI at baseline. Incident MI was defined by electrocardiogram or death certificate. The predicted risk of fatal MI, non-fatal MI, and both was calculated using Framingham score equations. Predicted to observed risk ratio of MI was estimated. RESULTS: There were 34 incident MI cases and 24 MI deaths (median follow-up 6.2 years). The score equations overestimated the prediction of incident MI and CHD death (ratio 2.27, 95% CI, 1.19-3.34) and incident MI (ratio 2.36, 95% CI, 1.07-3.65) in men. CONCLUSIONS: The Framingham score overestimated incident MI and CHD death risk in men; however, other studies are needed to confirm our results for recalibrating the score for Mexican subjects.

Diabetic by HbA1c, Normal by OGTT: A Frequent Finding in the Mexico City Diabetes Study.

CONTEXT: The agreement between glucose-based and hemoglobin A1c (HbA1c)-based American Diabetes Association criteria in the diagnosis of normal glucose tolerance, prediabetes, or diabetes is under scrutiny. A need to explore the issue among different populations exists. OBJECTIVE: Examine the results obtained with both methods in the diagnosis of the glycemic status. DESIGN: The Mexico City Diabetes Study is a population-based, prospective investigation. SETTING: Low-income elder urban community. PARTICIPANTS: All 854 participants without known diabetes had both oral glucose tolerance test (OGTT) and HbA1c measurements on the same day of the 2008 phase. INTERVENTIONS: Standardized protocol: questionnaires, anthropometry, and biomarkers. MAIN OUTCOME: Diagnostic classification of American Diabetes Association criteria. RESULTS: We found by OGTT normal glucose tolerance (NGT) in 512 (59.9%) participants, prediabetes [impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT)] in 261 (30.5%), and diabetes in 81 (9.4%). In total, 232 in the NGT group (45.3%) and 158 in the prediabetes group (60.5%) had HbA1c ≥6.5%. Body mass index, waist circumference, and blood pressure were significantly different among OGTT-defined diabetic status groups but not in the HbA1c-diagnosed group. We identified 404 participants in the NGT group with confirmed NGT throughout all phases of the Mexico City Diabetes Study. Of these, 184 (45.5%) had HbA1c ≥6.5%. In a vital/diabetes status follow-up performed subsequently, we found that, of these, 133 remained nondiabetic, 3 had prediabetes, 7 had diabetes, and 13 had died without diabetes; we were unable to ascertain the glycemic status in 5 and vital status in 23. CONCLUSIONS: Normal OGTT coexisting with elevated HbA1c is a common finding in this cohort. It is possible that this finding is not mediated by hyperglycemia. This might occur in similar populations.

Microalbuminuria as a predictor of myocardial infarction in a Mexican population: the Mexico City Diabetes Study.

OBJECTIVE: Our objective was to evaluate whether microalbuminuria predicts myocardial infarction (MI) in a Mexican population. METHODS: The study was a prospective, population-based cohort. Baseline examination was carried out in 1989; the first follow-up in 1993 and the second in 1997. All men and non-pregnant women between 35 and 64 years of age at the start of the study were considered eligible. Clinical, anthropometric, and laboratory characteristics were evaluated. All patients with macroalbuminuria at baseline were excluded from the present analyses, as were all prevalent cases with MI. Remaining patients were classified as with or without microalbuminuria. Incident cases of MI were identified during follow-up phases using an electrocardiogram (according to the Minnesota Code) or the death certificate (in which underlying cause of death was listed as MI, Causes of Death codes 410.0-410.9). Results. From 2196 individuals, 1586 satisfied the inclusion criteria. Two hundred fifteen (13.6%) had microalbuminuria, and 1371 (86.4%) did not. During follow-up, 10 patients with microalbuminuria and 31 patients without microalbuminuria developed an MI. Using robust logistic regression, the probability of developing MI, adjusting by Framingham score, was estimated to be 1.90 (95% CI,.97-3.72) times higher in patients with microalbuminuria as compared with patients without microalbuminuria. CONCLUSION: We found that in a Mexican population the relationship between microalbuminuria and incidence of MI was borderline statistically significant after adjusting for other cardiovascular risk factors.

Incidence of type 2 diabetes in Mexico: Results of The Mexico City Diabetes Study after 18 years of follow-up / Incidencia de diabetes tipo 2 en México: Resultados del Estudio de la Diabetes en la Ciudad de México después de 18 años de seguimiento

Objective. To estimate the incidence of type 2 diabetes (T2D) in Mexican population. Materials and methods. Population based prospective study. At baseline (1990), the population at risk (1939 non-diabetic adults 35-64 years) was evaluated with oral glucose tolerance test. Subsequent similar evaluations were done (1994, 1998, 2008). American Diabetes Association diagnostic criteria were applied. Results. The period of observation was 27842 person-years, the cumulative incidence of T2D was 14.4 and 13.7 per 1000 person-years for men and women, respectively. Incidence was 15.8, 15.7 and 12.7 per 1 000 person-years for the second (1994), third (1998) and fourth (2008) follow-up phases, respectively. The mean age at diagnosis was 44 years for prevalent cases and 56 years for incident cases. Conclusions. This is the first estimate of long-term incidence of T2D in Mexican population. The incidence is among the highest reported worldwide. It remained with few changes throughout the study period.

Objetivo. Estimar la incidencia de diabetes mellitus tipo 2 (T2D) en México. Material y métodos. Estudio prospectivo, de base poblacional. En el examen basal (1990) se evaluó a 1939 participantes normoglucémicos, con curva de tolerancia a la glucosa. Se realizó examen similar en tres evaluaciones subsecuentes (1994, 1998, 2008). Se aplicaron criterios recomendados por la American Diabetes Association. Resultados. En el tiempo de observación (27842 años persona), la incidencia acumulada de T2D fue de 14.4 y 13.7 por 1000 años persona en hombres y mujeres, respectivamente. En evaluaciones intermedias de (1994, 1998 y 2008) fue de 15.8, 15.7 y 12.7 por 1 000 años persona, respectivamente. Los casos prevalentes tuvieron edad promedio al diagnóstico de 44 años; los incidentes de 56 años. Conclusiones. Esta es la primera estimación a largo plazo de la incidencia de T2D en población mexicana. Los resultados se encuentran entre los más altos informados en el mundo.

Risk factors associated to diabetes in Mexican population and phenotype of the individuals who will convert to diabetes / Factores de riesgo asociados con diabetes en la población mexicana y fenotipo de los individuos que desarrollarán diabetes

Objective. To describe risk factors associated to the incidence of type 2 diabetes (T2D) in Mexican population and to define phenotypic (clinical, anthropometric, metabolic) characteristics present in the individual who will convert to diabetes, regardless of time of onset. Materials and methods. The Mexico City Diabetes Study began in 1990, with 2 282 participants, and had three subsequent phases: 1994, 1998, and 2008. A systematic evaluation with an oral glucose tolerance test was performed in each phase. For diagnosis of T2D, American Diabetes Association criteria were used. Results. The population at risk was 1939 individuals. Subjects who were in the converter stage (initially non diabetic that eventually converted to T2D) had, at baseline, higher BMI (30 vs 27), systolic blood pressure (119 vs 116 mmHg), fasting glucose (90 vs 82mg/dl), triglycerides (239 vs 196mg/dl), and cholesterol (192 vs 190mg/dl), compared with subjects who remained non converters (p<0.05). Conclusion. The phenotype described represents a potentially identifiable phase and a target for preventive intervention.

Objetivo. Describir los factores de riesgo asociados con la incidencia de diabetes tipo 2 (T2D) en la población mexicana, así como el fenotipo de los sujetos que desarrollarán diabetes, independientemente del tiempo que lleve el desarrollo de esta nueva condición. Material y métodos. El Estudio de la Diabetes de la Ciudad de México inició en 1990 y tuvo un total de 2 282 participantes a los que se dio seguimiento en tres ocasiones: 1994, 1998 y 2008. Se realizó una curva de tolerancia a la glucosa para diagnosticar T2D, para lo cual se siguieron los criterios de la Asociación Americana de Diabetes. Resultados. La población en riesgo fue de 1939 sujetos. Los individuos en proceso de desarrollo (aquellos inicialmente no diabéticos que desarrollaron T2D) mostraron niveles más altos de IMC (30 vs 27), presión arterial sistólica (119 vs 116 mmHg), glucosa en ayuno (90 vs 82 mg/dl), triglicéridos (239 vs 196 mg/dl) y colesterol (192 vs 190 mg/dl), comparados con los sujetos que no desarrollaron T2D (p<0.05). Conclusiones. El estado de los individuos que se convertirán en diabéticos es discernible y representa una fase del padecimiento con potencial para la prevención.

The status of diabetes care in Mexican population: are we making a difference? Results of the National Health and Nutrition Survey 2006 / El cuidado de la diabetes en población mexicana: ¿estamos siguiendo la estrategia correcta? Resultados de la Encuesta Nacional de Salud y Nutrición 2006

OBJECTIVE: Examine clinical indicators to evaluate diabetes care in Mexico. MATERIAL AND METHODS: Diabetics (self reported, with therapy) were examined with standardized questionnaires, anthropometry, glucose, lipids and glycohemoglobin. Data were analyzed statistically. RESULTS: There were 2 644 patients, 677 cases without access to medical care (73 percent women), most lived in rural communities and spoke aboriginal dialect. Prevalence of obesity for private access group was 21.2 percent, for other or non access group was between 31 and 65 percent. The group without or basic education was most common, 76 percent of the cases had HDL <40 mg/dl and 36 percent had hypertriglyceridemia. Only 6.6 percent of patients had HbA1c <7 percent. There was no significant difference between HbA1c values observed in the group with or without access. Most patients were treated with oral agents. A significant group was without therapy. Assessments for complications was infrequent. CONCLUSIONS: Current model for diabetes care in Mexico is inefficacious and a paradigm change is necessary.

OBJETIVO: Examinar indicadores para evaluar la atención de diabetes en México. MATERIAL Y MÉTODOS: Se examinaron diabéticos (autorreportados, con tratamiento) con cuestionario estandarizado, antropometría, glucosa, lípidos y hemoglobina glucosilada. Los datos se analizaron estadísticamente. RESULTADOS: De 2 644 casos, 677 no tenían acceso a atención médica (73 por ciento mujeres), la mayoría eran de comunidades rurales y hablaban un dialecto indígena. La prevalencia de obesidad en el grupo con acceso privado fue 21,2 por ciento; en personas con otro o sin acceso, fue entre 31 y 65 por ciento. El grupo sin o con educación básica fue el más común. El 76 por ciento de los casos tenían colesterol HDL <40 mg/dl y 36 por ciento tenía hipertrigliceridemia. Sólo 6.6 por ciento tenían la HbA1c <7 por ciento. No hubo diferencias entre valores de HbA1c en el grupo con o sin acceso. La mayoría recibían hipoglucemiantes orales, muchos sin tratamiento. La evaluación de complicaciones fue infrecuente. CONCLUSIONES: El modelo de atención de diabetes en México es ineficaz y es preciso cambiar de paradigma.

Retinopatía diabética: aspectos para su detección y tratamiento: una propuesta terapéutica / Diabetic retinopathy: practical aspects for its detection and treatment: an integral therapeutic proposal

El propósito de la presente revisión es generar interés en la comunidad médica para involucrarse en nuestro país con el proyecto ®Diabetes 2000¼ o ®Eliminación de ceguera prevenible por diabetes para el año 2000¼. Es un programa educacional a largo plazo cuya prioridad es proveer los resultados de investigación más reciente a oftalmólogos, médicos de primer contacto y profesionales de la salud, seguido además de educación del paciente diabético y público en general. Estos programas son necesarios para asegurar una transferencia efectiva de los resultados de la investigación clínicamente aplicables a la práctica diaria. El objetivo final será la detección oportuna y el tratamiento adecuado con láser de la retinopatía diabética, utilizando los lineamientos establecidos por estudios sólidos reconocidos internacionalmente y prevenir la ceguera. En esta revisión se analizan, de manera sencilla y útil para el médico de primer contacto, cierta información esencial relacionada con la retinopatía diabética, aspectos epidemiológicos en nuestro país, criterios de referencia y la utilidad del diagnóstico y tratamiento oportunos

Diabetic retinopathy in Mexico: prevalence and clinical characteristics

We present the result of a population based study designed to estimate the prevalence of diabetic retinopathy in a series of 284 type 2 diabetics residing in low income areas of Mexico city. These patients were identified in a survey performed between february 1990 and october 1992 (The Mexico City Diabetes study). We located 214 (75.35 per cent) of the original 284 patients and invited them to attend a clinic where they were interviewed and had a complete opthalmologic examination. All participant had, in addition to the retinal examination by a certified opthalmologist, seven fields stereo fundus photographs taken with a Topcon 50X retinal camera. Photos were taken using ASA 100 Kodak film and processed in their laboratory. All photographs were read and graded for quality and level of diabetic retinopathy (DR) in the Reading Center of the Department of Ophthalmology of the University of Winsconsin. A total of 37 (43.5 per cent) men and 69 (53.5 per cent) women had no evidence of DR. In 16 (18.8 per cent) men and 21 (16.3 per cent) women there was background DR. In 25 (29.4 per cent) men and 30 (23.3 per cent) women there was preproliferative DR. In 5 (5.9 per cent) men and in 7 (5.4 per cent) women there was proliferative DR. Macular edema was diagnosed in 7(8.2 per cent) men and 6 (4.7 per cent) women, of these in 3 (3.5 per cent) men and in 5 (3.9 per cent) women the macular edema was central. There was an association of duration of DM, level of fasting hyuperglycemia and microalbuminuria with the presence of DR. In 5 (7.5 per cent) men and in 7 (10.5 per cent) women with sight threatening DR, the microvascular complication had been previously undiagnosed and untreated. We conclude that DR is very common in Mexican diabetic. This complication is associated with duration of diabetes, chronic poor metabolic control and microalbuminuria. A very significant proportion of cases with sight threatening DR remains undiagnosed and untreated. Consequently there is a significant number of cases developing into blindness that could have been prevented

Incidencia y progresión de la retinopatía diabética en población de nivel socioeconómico bajo de la Ciudad de México / Incidence and progression of diabetic retinopathy in low income population of Mexico city

La retinopatía diabética es de las principales causas de ceguera prevenible en población económicamente activa. La diabetes mellitus afecta frecuentemente a la población mexicana, la retinopatía diabética como complicación microvascular también es frecuente y adquiere formas clínicas más severas cuando se ha comparado con otras poblaciones. No existe ningún estudio de incidencia de esta complicación diabética en nuestro país. En esta investigación, se informa la incidencia y progresión a cuatro años de la retinopatía diabética en una cohorte de pacientes diabéticos tipo 2 habitantes de seis colonias de bajos recursos de la ciudad de México. En la fase de seguimiento, a cuatro años se logró examinar a 164 (76.6 por ciento) del total de la población estudiada en fase inicial, 63 hombres y 101 mujeres. A todos se les realizó un examen oftalmológico completo con esterofotografías de fondo de ojo de siete campos. Estas fotografías fueron graduadas con los criterios internacionalmente aceptados en el Centro de Lectura Fotográfica de nuestra institución. Se concluyó que la incidencia a cuatro años de retinopatía diabética, de cualquier grado es de 22.5 por ciento. Se presentó progresión en 20.6 por ciento y 4.5 por ciento alcanzó la etapa de retinopatía diabética proliferativa. La incidencia se asoció a edad menor de 45 años en el momento del diagnóstico de diabetes mellitus y la progresión, a más de 10 años de tiempo de evolución del padecimiento. La incidencia de edema macular a cuatro es de 8.8 por ciento. Es muy importante difundir estos datos para incrementar el nivel de conciencia y desarrollar estrategias de prevención y atención al paciente diabético en nuestro país

Prevalence of gallbladder disease and associated clinical variables in a low income population of Mexico City

We present the results of a population-bases syrvery carried out in a low income area of Mexico City. The aim of this study is to characterize the prevalence of clinically significant gallbladder disease (CSGD) using the self-reported history of cholecystectomy (CG) or cholelithiasis (CL) demonstrated by cholecystography and/or ultrasonography. The population of the studied area was 15,532 ihabitants, of whom 3505 (22.6 percent) were age elegible (35 - 64 year-old men and non-pregnant women). Home interview were obtained in 2810 (80.2 percent). A physical and laboratory examination was performed in 2282 individuals (65.1 percent; 941 men and 1341 women). The prevalence of CSGD in men was 2.0 percent (95 percent confidence intervals 1.1 - 2.9 percent) and 9.2 percent in women (95 percent confidence intervals 7.7 - 10.7 percent). Patients with CSGD were older, emn (p <0.003) and women (p <0.001). Women with CSGD had higher waist to hip circumference ratio (p <0.06), higher fasting glucose (p <0.03) as well as 2 h post challenge glycemia (p <0.04) and insulinemia (p <0.03) In the multiple logistic regression model only age (p <0.001) and sex (p <0.001) remained significantly associated. We conclude that CSGD is quite prevalent in this population. Is is associated with age in both genders and in women, higher glucose and insulin levels. The prospective follow-up of this cohort is important since it copuld generate the information needed to implement a preventive program to diminish the impact of this condition

Nephropathy in low income diabetics: the Mexico City diabetes study

Among the most serious complications associated with diabetes mellitus (DM) is nephropathy (DN). In Mexico, there is little information on the frequency and clinical characteristics of DN in the Mexican population. We present results of a population-based survey designed to estimate the prevalence of DN. The low income population consisted of 15,532 inhabitants. All 35- to 64-year-old males and non-pregnant women residing in the survey area were identified as eligible for the study (3505; 22.6 percent). A home interview was obtained in 2810 (80.2 percent). A physical exam with oral glucose tolerance test wasobtained in 2282 (81.2 percent of those interviewed). DM was diagnosed in 304 (crude rate 13.3 percent). Mean age for men and women with DM was 51.6 ñ 8.4 and 52.2 ñ 7.5, respectively. Duration of DM in men was 9.2 ñ 8.1 and in women, 7.3 ñ 6.7 years. Hypertension was diagnosed in 19.8 percent of men and 18.1 percent of women. Diabetic retinopathy of any level was found in 55.4 percent of men and 45.7 percent of women. Mean glycohemoglobin in men was 9.6 ñ 2.1 and in women 9.5 ñ 2.2 percent (normal 4 - 8 percent). At baseline, proteinuria (1+ or more, by dipstick) was found in 24.7 percent of men and 9.6 percent of women, microalbuminuria (MA) in 84.4 percent of men and 63.8 percent of women. Quantitative albuminuria was abnormally high in 54.7 percent of men and 40.3 percent or women. In the 203 diabetic studied with 24 h urine collection from creatinine clearance, normal renal function was found in 69.1 percent of men and 47.5 percent of women, reduced renal function was found in 26 percent of men and 50 percent of women, ranl insufficiency was diagnosed in 4.9 percent of men and 1.6 percent of women. One patient was on dialysis and in a subsequent follow up, we found that 2.3 percent of the patients had died of renal failure, six men (46 -63 years) and a woman of 62 years. We concluded that DN is a very serious threat to this population. The high case fatality rate associatd with this condition maintains a low prevalence. It is important to develop a program to diminish the frequency of this condition

A diabetic retinopathy screening program as a strategy for blindness prevention

The most frequent cause of preventable blindness in adults, in the developed world, is diabetic retinopathy (DR). the early treatable phase of this complication is clinically silent. In order to institute effectiv elaser photocoagulation and prevention of blindness, timely detection is crucial. Consequently there is a nedd for periodic funduscopic examinations of all diabetics. Due to the high prevalence of DM in Mexico most of the primary care facilities are limited. We present the results of a DR screening program (DRSP) using a mobile unit equipped with a fundus photography camera, parked outside of a clinic. We report the prevalence of the various stages of DR and clinical characteristics observed in this population as well as our experience working in such an environment. Th estudy period was from september 1 to december 22, 1995. All the diabetics that presented for care to the clinica were identified and all other persons were invited to participate. A total of 231 participants were invited (112 men, 119 women). Non- stereo fundus photos of two retinal fields (macula and optic disk centered) were taken with techique and classification according to international standards. Response rate to the invitation was 95.3 percent. Mean age was 62.4 ñ 13 years and 63.5 ñ 10 years and duration of diabetes was 12.3 ñ 10.1 years and 11.0 ñ 7.5 years for men and women, respectively. DR was detected in 38 percent of the caes, of these only 5.6 percent have received treatment. DR was uncovered in 84.5 percent of the cases and was associated with duration of diabetes (p<0.001 in men and p=0.04 in women) and hyperglycemia (in men p<005, only). DR has a high prevalence in this population and can be detected through a screening program which rveals undiagnosed hig risk DR in an efficient, and standardized manner

High prevalence of cholelithiasis in a low income mexican population: An ultrasonographic syrvey

The authors present the result of a population based survey of cholelititasis carried out in a low income area of Mexico city using high resolution gallbladder ultrasound. The purpose of the study was to estimate the prevalence and selected associated risk factors of cholelithiasis (CL). The population of the studied area was 15,532 subjects, of whom 3,505 (22.6 percent) were eligible for the baseline survey (men and non-pregnant women between 35-64 years of age). Of this group, 1,735 (76.03 percent, 702 men and 1,033 women) were located for a follow-up study. Ultrasonography was performed on all except for 100 subjects who had undergone previous cholecystectomy. Crude prevalence of CL was 14.1 percent (95 percent CI 12.5-15.5). The prevalence was 5.8 percent (95 percent CI 4.1-7.5) in men and 19.7 percent (95 percent CI 17-3-22.1) in women. Presence of gallstones was associated with age, sex (men p<0.006, women p<0.001), and multiparity (p<0.002). Centrality index in men and body mass index in women were positive and significantly associated with CL when compared with subjects without CL. High levels of fasting and post glucose load insulin in women and men respectively were associated with CL. The authors conclude that the population of this study has a high prevalence of CL and confirm some know risk factors such as age, sex, BMI and multiparity. Proper assessment of the magnitude problem and characterization of potentially modifiable risk factors will play a major role in preventing this pathology