Recent developments in the epidemiology of diabetes in the Americas.

The prevalence of diabetes recorded in population surveys in the American region varies from < 1% (rural Mapuche Indians aged 20 years and over, Chile) to almost 50% (Pima Indians aged 20 years and over, United States of America). The prevalence of non-insulin-dependent diabetes mellitus (NIDDM) was approximately 2.5 times higher among Mexican Americans than in non-Hispanic white Americans. In the Mexican Americans, prevalence followed a sociocultural gradient: 16% in low-income barrios, about 10% in middle-income neighbourhoods and 5% in high-income suburbs in San Antonio, Texas. Data from the Hispanic Health and Nutrition Examination Survey indicate prevalence of diabetes in the age range 45-74 years of 24% for Mexican Americans, 26% for Puerto Ricans and 16% for Cuban Americans, compared to 12% for non-Hispanic whites. Figures for a low-income district of Mexico City show a 36% lower prevalence than for Mexican Americans in the USA. Prevalence in Brazil is approximately 7% in subjects aged 30-69 years. Black Americans have a relatively high prevalence of NIDDM, though not as high as the Mexican Americans. There is evidence that complications of diabetes may vary between populations, and that they may be particularly severe in Mexican Americans, and higher in black than in white Americans. The extent to which these differences relate to access to health care and treatment remains to be clarified.     

Access to health care for migrants returning to Mexico

Continued migration from Mexico over the past several decades has created a large population of elderly Mexicans in the U.S. There is no system in Mexico for those Mexicans who would like to retire there to obtain health insurance during their retirement years. Using a nationally representative dataset of Mexican elders, we explore the current state of health insurance status for Mexican elders with a history of migration to the U.S. We find a robust negative association between years spent in the U.S. and the probability of being insured. Coordination between the U.S. and Mexico on policy options to insure Mexicans migrants may prove beneficial to the social security systems in both countries as well as to migrants themselves.     

Diabetes-related mortality among Mexican Americans, Puerto Ricans, and Cuban Americans in the United States.

OBJECTIVES: Hispanics are the most rapidly growing minority group in the United States, and Mexican Americans, Puerto Ricans and Cuban Americans are the three largest Hispanic subgroups. Among Hispanics, type 2 diabetes is the fifth leading cause of death. This paper examines diabetes-related mortality in Mexican Americans, Puerto Ricans, and Cuban Americans over 35 years of age in the United States during 1996 and 1997. METHODS: Using data from the National Vital Statistics System and the 1990 and 2000 censuses, we calculated age-adjusted and age-specific diabetes-related death rates for Mexican Americans, Puerto Ricans, and Cuban Americans over 35 years of age. Diabetes-related deaths were determined to be any death for which diabetes was coded as either the underlying or contributing cause of death. RESULTS: The diabetes-related mortality rate for Mexican Americans (251 per 100,000) and Puerto Ricans (204 deaths per 100,000) was twice as high as the diabetes-related mortality rate for Cuban Americans (101 deaths per 100,000). Cuban American decedents had the highest proportion of deaths with diabetes coded as the underlying cause of death (44%). After diabetes, heart disease (31%) followed by cancer (8%) and stroke (6%) were the most frequent primary underlying causes of diabetes-related deaths in all three ethnic groups. CONCLUSION: Our analyses of these data demonstrate that diabetes-related mortality differed among Mexican Americans, Puerto Ricans and Cuban Americans more than 35 years of age in the United States in 1996 and 1997. Socioeconomic factors such as low educational attainment and low income may be factors that contributed to the disparities in these mortality rates for different subgroups. Further research is needed to update these findings and to investigate explanatory risk factors. Diversity among Hispanic subgroups has persisted in recent years and should be considered when health policies and services targeted at these populations are developed.     

Diabetes is a major cause of influenza-associated mortality in Mexico

BackgroundInfluenza is a major cause of mortality worldwide. Most influenza-associated deaths are associated with cardiovascular or respiratory disorders. However, a large proportion of influenza-associated deaths do not have respiratory or cardiovascular disorders declared as the underlying cause of death. Diabetic individuals are at increased risk for influenza-mortality. In this study, we assessed the contribution of diabetes to influenza-associated mortality in Mexico.MethodsDiabetes influenza-associated mortality was estimated for the Mexican population using National Mortality Databases from the Mexican Ministry of Health from 1998 through 2015. Diabetes influenza-associated mortality was calculated applying Serfling cyclical regression models to weekly mortality rates for persons 20–59 years, 60 and more years, and all ages, and by sex.ResultsThere was a high correlation between weekly pneumonia and influenza mortality and diabetes-related mortality. Yearly influenza-associated diabetes mortality rates varied between 2.0 and 5.9/100,000. Up until the 2005–2006 season, diabetes-associated mortality rates were higher in females, while after that season rates were higher in males. Yearly influenza-associated diabetes mortality rates for adults 20–59 years of age ranged between 1.7 and 3.4/100,000, while estimates for adults 60 years and older ranged between 16.3 and 46.1/100,000. Approximately one third of estimated diabetes influenza-associated deaths occurred in adults 20–59 years of age. On average, diabetes deaths accounted for 19.6% of estimated influenza-associated all-cause mortality.ConclusionDiabetes is a major cause of estimated influenza-associated mortality in Mexico. Health-care authorities and professionals in countries with high diabetes prevalence should be aware of the potential impact of influenza in individuals with this condition.     

Early onset type 2 diabetes in Jamaica and in Mexico. Opportunities derived from an interethnic study

Populations with Amerindian or African heritages are the one with the highest prevalence of diabetes worldwide. A large percentage of these individuals survived famine. However, the survival effect has become detrimental to their descendents living in an environment of caloric surplus. In countries, like Mexico and Jamaica, in which diabetes is highly prevalent, the onset of the disease happens at earlier ages. Our objective is to summarize diabetes data from Mexico and Jamaica and to discuss the opportunities that can result from an interethnic study. On one hand, the prevalence of diabetes in Jamaica is 17.9% in the 15+ age group. Jamaican researchers have built a cohort of families with early onset type 2 diabetes. In this population, this form of the disease is unrelated to MODY genes. On the other hand, the prevalence of diabetes in adult Mexicans is 14.4%. The group in which the greater percentual changes have occurred is the adults who are below the age of 40. More than two thirds of the early onset cases studied have a body mass index that is >25 kg/m2 and the clinical characteristics of metabolic syndrome. A minority of them has mutations in the MODY genes. The joint study of Mexican and Jamaican cohorts of early onset type 2 diabetes cases will be useful to identify new genetic and environmental players in the pathogenesis of this entity.     

Cost-effectiveness of rotavirus vaccination in Ghana: Examining impacts from 2012 to 2031

BackgroundDiarrhea causes about 10% of all deaths in children under five years globally, with rotavirus causing about 40% of all diarrhea deaths. Ghana introduced rotavirus vaccination as part of routine immunization in 2012 and it has been shown to be effective in reducing disease burden in children under five years. Ghana’s transition from low to lower-middle income status in 2010 implies fewer resources from Gavi as well as other major global financing mechanisms. Ghana will soon bear the full cost of vaccines. The aim of this study was to estimate the health impact, costs and cost-effectiveness of rotavirus vaccination in Ghana from introduction and beyond the Gavi transition.MethodsThe TRIVAC model is used to estimate costs and effects of rotavirus vaccination from 2012 through 2031. Model inputs include demographics, disease burden, health system structure, health care utilization and costs as well as vaccine cost, coverage, and efficacy. Model inputs came from local data, the international literature and expert consultation. Costs were examined from the health system and societal perspectives.ResultsThe results show that continued rotavirus vaccination could avert more than 2.2 million cases and 8900 deaths while saving US$6 to US$9 million in costs over a 20-year period. The net cost of vaccination program is approximately US$60 million over the same period. The societal cost per DALY averted is US$238 to US$332 with cost per case averted ranging from US$27 to US$38. The cost per death averted is approximately US$7000.ConclusionThe analysis shows that continued rotavirus vaccination will be highly cost-effective, even for the period during which Ghana will assume responsibility for purchasing vaccines after transition from Gavi support.     

The Rural–Urban Divide: Health Services Utilization Among Older Mexicans in Mexico

Context: Mexico. Purpose: Using the health care service utilization model as a framework, this paper will analyze the differences in health care service use among older Mexicans living in urban and rural areas in Mexico. Methods: The Mexican Health and Aging Survey (MHAS) data were used to test the applicability of Andersen's “model of health services” of predisposing (ie, age, sex, etc.), enabling (education, insurance coverage, etc.) and need factors (diabetes, hypertension, etc.) to predict ever being in the hospital and physician visits in the past year by place of residence (urban, rural, semi-rural). Findings: Results showed that older Mexicans living in the most rural areas (populations of 2,500 or fewer) were significantly less likely to have been hospitalized in the previous year and visited the physician less often (P < .0001) than their urban counterparts. The significant difference in hospitalization between rural and urban residing older Mexicans was largely accounted for by having health care coverage. Certain need factors such as diabetes, previous heart attack, hypertension, depression, and functional limitations predicted frequency of physician visits and hospitalization, but they did not explain variations between rural and urban older Mexicans. Conclusions: Not having insurance coverage was associated with a lower likelihood of spending an overnight visit in the hospital and visiting a physician for older Mexicans. This lower utilization may be due to barriers to access rather than better health.     

Carga de la mortalidad por diabetes mellitus en América Latina 2000-2011: los casos de Argentina,Chile, Colombia y México

ObjectiveTo analyze trends in mortality in Argentina, Chile, Colombia and Mexico, between 2000 and 2011, by sex and 5-year age groups (between 20 and 79 years of age).Material and methodsMortality vital statistics and census data or projected population estimates were used for each country. Age-specific mortality rates and the years of life lost were calculated.ResultsAmong the countries analyzed, Mexico had the highest mortality rate and lost the most years of life due to diabetes. Between 2000 and 2011, Mexicans lost an average of 1.13 years of life, while Colombia (0.24), Argentina (0.21) and Chile (0.18) lost considerably fewer life years. In general, deaths from diabetes were higher in men than in women except in Colombia. Nearly 80% of years of life lost due to diabetes occurred between 50 and 74 years of age in the four countries.DiscussionDiabetes is a huge challenge for Latin America, especially in Mexico where mortality due to diabetes is accelerating. Even though the proportion of deaths due to diabetes in Argentina, Chile and Colombia is smaller, this disease figures among the main causes of death in these countries.     

Diabetes among Mexican Americans in Starr County, Texas

An increasing body of evidence suggests that diabetes mellitus constitutes a major health burden among the Mexican-American population. For example, county-wide death rates in Texas attributable to diabetes from 1970-1981 range from 2.5-52.0 diabetes deaths per 1000 total deaths with the highest rates generally occurring in counties whose populations are more than 75% Spanish ancestry. To assess the prevalence and morbidity of noninsulin-dependent diabetes mellitus among Mexican Americans, 14% of the Starr County, Texas, population (97% Mexican-American) was randomly sampled. The reference population, sampling strategy, and screening results are described. Age-specific prevalences of diabetes for males ranged from 0% in males aged 15-24 years to 17.6% in those above 75 years of age. Rates for females ranged from 0.4% in those aged 15-24 years to a high of 19.0% in the 55- to 64-year age group. In both sexes, the rates are relatively low for persons under age 45 with a sharp increase in those aged 45-54 years and high rates prevailing in the older age groups. Comparisons of the rates in Starr County to those of the general US population indicate a two- to fivefold greater risk in Starr County. In terms of impact on this community, these results imply that over 50% of individuals older than 35 years are directly affected by diabetes by virtue of their having the disease or by being a first-degree relative of a diabetic.     

Racial disparities in diabetes mortality among persons aged 1-19 years--United States, 1979-2004

Diabetes is a chronic disease with a U.S. prevalence of 18 cases per 10,000 youths aged <20 years. With proper management and access to care, morbidity and mortality from diabetes are preventable, particularly in the pediatric population. Although diabetes is more common among non-Hispanic white youths, some studies report higher death rates among racial/ethnic minorities and among those in lower socioeconomic strata. In 2004, age-adjusted diabetes death rates for black persons in the United States were approximately twice those for white persons. However, no recent studies on racial disparities that focus specifically on the pediatric population have been conducted. To assess racial disparities in diabetes mortality among youths, CDC analyzed data on deaths with an underlying cause of diabetes among persons aged 1-19 years for the period 1979-2004. This report summarizes the results of that analysis, which determined that, during 1979-2004, diabetes death rates for black youths were approximately twice those for white youths. During 2003-2004, the annual average diabetes death rate per 1 million youths was 2.46 for black youths and 0.91 for white youths. Further study is needed to discern the specific reasons for increased diabetes mortality in black youths. Better identification and management of the disease among youths, especially among black youths, might help decrease racial disparities and prevent deaths from diabetes.     

Risk Factors for Liver Disease and Associated Knowledge and Practices Among Mexican Adults in the US and Mexico

Latinos in the US are disproportionately affected by chronic liver disease, which is the sixth most common cause of death among this group. In Mexico, cirrhosis and other liver diseases are the fourth leading cause of general mortality. The objective of this study was to contrast the liver disease risk factors, knowledge, and prevention practices reported among separate samples of Mexicans living in Los Angeles, CA and in Cuernavaca, Mexico. We assessed the prevalence of specific risk factors (body mass index, waist circumference, and alcohol consumption), the level of knowledge about liver disease in general, hepatitis B (HBV), and hepatitis C (HCV), as well as prevention activities such as screening and vaccination. Data were collected from in-person interviews and anthropometric measures obtained from Mexican adults aged 18–70 years. Chi-square and t tests were used to compare the results between groups. Numerous similarities were observed in the bi-national samples, including high prevalence of obesity, abdominal obesity, and high levels of alcohol consumption. Most participants in both countries recognized that excessive alcohol consumption is a risk factor for liver disease, but only 60% correctly identified hepatitis C, being overweight or obese, or having diabetes as risk factors. Few participants reported having been screened for HBV or HCV, vaccinated for HBV, or having the intention of getting screened for HBV or HCV. US participants reported significantly higher levels of prevention activities and screening intentions than those in Mexico. Identifying the specific risk factors, levels of knowledge and prevention activities that affect specific racial/ethnic populations is important in order to effectively target efforts to prevent liver disease.     

Cost-Effectiveness of Maraviroc for Antiretroviral Treatment-Experienced HIV-infected Individuals in Mexico

ObjectiveMaraviroc is the first approved drug in a new class of antiretrovirals, the CCR5 antagonists. The objective of this study was to predict the long-term clinical impact and cost-effectiveness of maraviroc in treatment-experienced adults with HIV/AIDS in Mexico.MethodsThe AntiRetroviral Analysis by Monte Carlo Individual Simulation (ARAMIS) model was adapted to the Mexican context to predict clinical and economic outcomes of treating with optimized background therapy (OBT) versus testing for viral tropism status and treating with OBT ± maraviroc accordingly in treatment-experienced adults in Mexico. Baseline characteristics and efficacy were from the MOTIVATE trials' screening cohort. Costs and population mortality data were specific to Mexico. Results were reported from the perspective of health care payers in 2008 Mexican pesos (converted to 2008 US$ in parentheses).ResultsCompared to treatment with OBT alone, treatment with OBT ± maraviroc contingent on tropism test result increased projected undiscounted life expectancy and discounted quality-adjusted life expectancy from 7.54 to 8.71 years and 4.42 to 4.92 quality-adjusted life years (QALYs), respectively, at an incremental cost of $228,215 (US$21,329). The resultant incremental cost-effectiveness ratio (ICER) was $453,978 (US$42,429) per QALY gained. The ICER was somewhat lower when maraviroc was modeled in individuals susceptible to ≤2 components of OBT ($407,329; US$38,069), while the ICER was higher in individuals susceptible to ≥3 OBT components ($718,718; US$67,171).ConclusionIn treatment-experienced individuals with HIV/AIDS in Mexico, maraviroc may be cost-effective, particularly in individuals with limited options for active antiretroviral therapy (ART).     

A POPULATION-BASED DIABETES REGISTER — DEVELOPMENT & APPLICATIONS

Population-based registers for chronic disorders are invaluable for better understanding the epidemiology, aetiology and natural history of a particular disorder. Insulin-dependent diabetes mellitus is one example where registers have been used. The disorder often develops at a relatively young age continuing throughout life with adverse influences on health, frequently causing premature mortality. It is well suited to systematised data collection and register development. In this paper, the rationale for registers is considered and methods used in development of a diabetes register in the Canterbury region of New Zealand (pop. one-third of a million) are described. A preliminary analysis of data using prevalence date of 1 January 1984, has shown that there are 1,148 (M = 574, F = 574) insulin-treated diabetic persons on the register. Ages range from two to 93 years (median = 52 years). Only 11.1 per cent of the diabetic population were aged under 20 years whereas 27 per cent were 65 or more years of age. Duration of diabetes was one to 58 years (median = 12 years). Only 28 per cent of cases had presented with diabetes at age under 20 years, most being diagnosed in adult life. The overall prevalence of insulin-treated diabetes was 3.3 per 1,000 population and peak prevalence was observed in those aged 60–69 years (7.5 per 1,000). Ongoing research with this register will document the natural history of the disorder, its morbidity and mortality, and will measure the use of secondary health care resources, particularly in-patient services.     

Cysticercosis-related deaths, California

Cysticercosis is an increasingly important disease in the United States, but information on the occurrence of related deaths is limited. We examined data from California death certificates for the 12-year period 1989-2000. A total of 124 cysticercosis deaths were identified, representing a crude 12-year death rate of 3.9 per million population (95% confidence interval [CI] 3.2 to 4.6). Eighty-two (66%) of the case-patients were male; 42 (34%) were female. The median age at death was 34.5 years (range 7-81 years). Most patients (107, 86.3%) were foreign-born, and 90 (72.6%) had emigrated from Mexico. Seventeen (13.7%) deaths occurred in U.S.-born residents. Cysticercosis death rates were higher in Latino residents of California (13.0/106) than in other racial/ethnic groups (0.4/106), in males (5.2/106) than in females (2.7/106), and in persons >14 years of age (5.0/106). Cysticercosis is a preventable cause of premature death, particularly among young Latino persons in California and may be a more common cause of death in the United States than previously recognized.     

Human T-cell lymphotropic virus testing of blood donors in Norway: a cost-effect model

BACKGROUND: Human T-cell lymphotropic virus type I and II (HTLV-I and II) are human retroviruses that can be transmitted by transfusion of whole blood. An HTLV-I infection is associated with adult T-cell leukaemia (ATL) and with tropical spastic paraparesis (TSP). Antibody tests from 5.5 million European blood donors have shown that the HTLV prevalence is low, ranging from 0 to 0.02%. This paper examines costs and effects associated with the intervention of testing all new blood donors for HTLV. METHODS: A mathematical model was used to calculate the number of cases prevented by the intervention. For a given prevalence of HTLV in the blood donor population, the model calculates the number of recipients infected by transfusion, and the number of partners and offspring that will in turn be infected. The model then calculates the number of subjects with disease due to HTLV-I infection and the number of deaths from disease. From these numbers the measures of cost and effect are calculated. RESULTS: Testing all new blood donors for HTLV is calculated to cost US$ 9.2 million per life saved, or US$ 420,000 per quality adjusted life year gained by the intervention, when the HTLV prevalence among donors is 1 per 100,000. When the prevalence among donors is 10 per 100,000 the intervention will cost US$ 0.9 million per life saved, or US$ 41,000 per quality adjusted life year gained. The same analysis shows that testing blood donors for human immunodeficiency virus (HIV) saves money when the HIV prevalence among donors is above 0.7 per 100,000. CONCLUSION: For Norway, studies suggest a willingness to pay to save a statistical life of approximately US$ 1.2 million. The costs fall under this value when the number of infected persons is > or = 8 per 100,000 donors. The results are uncertain because of the uncertainty in HTLV infection and disease parameters.     

"Only the best class of immigration": public health policy toward Mexicans and Filipinos in Los Angeles, 1910-1940

Public health officials contributed to the early 20th-century campaign against Mexicans and Filipinos in Los Angeles. In 1914, the newly established city and county health departments confronted the overwhelming task of building a public health infrastructure for a rapidly growing population spread over a large area. However, for several years public health reports focused almost exclusively on the various infectious diseases associated with Mexican immigrants.Although the segregation of Mexicans was illegal in California until 1935, county officials established separate clinics for Whites and Mexicans during the 1920s. With assistance from state officials, local health authorities participated actively in efforts to restrict Mexican immigration throughout the 1920s and to expel both Mexicans and Filipinos during the 1930s.     

Assessment of the economic impact of the antiretroviral vaccine in Venezuela]

OBJECTIVE: To assess the cost of medical care for rotavirus gastroenteritis and the cost-effectiveness of the antiretroviral vaccine in Venezuelan children under five. METHODS: We used an economic model that comprises epidemiologic information, vaccine efficacy, and the cost of medical care in connection with rotavirus gastroenteritis, viewed from a social perspective. In order to determine the effectiveness of the vaccine, we estimated the number of hospitalized cases, of medical visits, and of deaths averted after vaccination. The cost-effectiveness of the vaccine was determined on the basis of the number of disability-adjusted life years (DALYs) and cases averted. RESULTS: In Venezuela, health services spend approximately 4.2 million US$ yearly on covering the costs of medical care for rotavirus-related disease. In a vaccinated cohort, an antiretroviral vaccination program would prevent around 52% (186) of the deaths, 54% (7,232) of the hospitalizations, and 50% (55,168) of the ambulatory visits that take place during the first five years of life. For an estimated cost of approximately 24 US$ per individual vaccination schedule, the cost-effectiveness ratio obtained is 1,352 US$ per DALY. CONCLUSIONS: The results of this study suggest that antiretroviral vaccination is a cost-effective strategy for preventing rotavirus gastroenteritis in Venezuela, since it can prevent deaths and DALYs in the population under five years of age.     

A Transnational Study of Migration and Smoking Behavior in the Mexican-Origin Population

Objectives. We examined migration-related changes in smoking behavior in the transnational Mexican-origin population.Methods. We combined epidemiological surveys from Mexico (Mexican National Comorbidity Survey) and the United States (Collaborative Psychiatric Epidemiology Surveys). We compared 4 groups with increasing US contact with respect to smoking initiation, persistence, and daily cigarette consumption: Mexicans with no migrant in their family, Mexicans with a migrant in their family or previous migration experience, migrants, and US-born Mexican Americans.Results. Compared with Mexicans with a migrant in their family or previous migration experience, migrants were less likely to initiate smoking (odds ratio [OR] = 0.56; 95% confidence interval [CI] = 0.38, 0.83) and less likely to be persistent smokers (OR = 0.41; 95% CI = 0.26, 0.63). Among daily smokers, the US-born smoked more cigarettes per day than did Mexicans with a migrant in their family or previous migration experience for men (7.8 vs 6.5) and women (8.6 vs 4.3).Conclusions. Evidence suggests that smoking is suppressed among migrants relative to the broader transnational Mexican-origin population. The pattern of low daily cigarette consumption among US-born Mexican Americans, noted in previous research, represents an increase relative to smokers in Mexico.Epidemiological studies have found large differences in smoking between Latinos and non-Hispanic Whites in the United States. Latinos are less likely than non-Hispanic Whites to initiate smoking. For instance, in the 2003 Tobacco Use Supplement to the Current Population Survey (CPS), a large nationally representative sample, the lifetime prevalence of smoking was 25% among Latinos and 44% among non-Hispanic Whites.1 Among smokers, Latinos are more likely to be nondaily smokers2–4 and smoke fewer cigarettes per day3 than non-Hispanic Whites. The 2003 CPS found that 36% of Latino smokers were nondaily smokers, compared with 17% of non-Hispanic White smokers and that among daily smokers 63% of Latinos smoked 10 or fewer cigarettes per day, compared with only 29% of non-Hispanic Whites.3 A recent study suggests that differences in smoking account for close to three quarters of the advantage in life expectancy at age 50 years that Latinos have relative to non-Hispanic Whites.5The immigrant origins of a large portion of the Latino population may be one factor contributing to these differences. Immigrant Latinos are less likely to be current smokers than are US-born Latinos,6–9 leading some to suggest that there may be positive selection among immigrants. However, our previous study found that in the years before arrival in the United State, migrants were more likely to have smoked than the general Mexican population.10 In addition, the increase in smoking in 2nd and higher generations of Latinos suggests that the distinctive patterns among immigrants become less common with assimilation and, therefore, that the differences in lifetime smoking patterns may narrow or disappear as the US-born portion of the Latino population grows.11 However, no information is available on the extent to which the distinctive patterns of smoking among Latinos reflect continuity with the source population in the countries of origin of Latino immigrants or environmental influences on migrants and their US-born descendants that occur in the context of assimilation.We examined the trajectory of smoking behaviors related to migration and assimilation to the United States across the transnational Mexican-origin population of Mexico and the United States. Mexican Americans constitute more than 60% of the US Latino population, and about 40% of Mexican Americans were born in Mexico.12 Immigrants from Mexico are by far the largest group of immigrants in the United States, constituting about 30% of the total foreign-born population.12 Combining population-based surveys from both countries, we examined differences in initiation and cessation of smoking and in cigarette consumption among daily smokers across a series of groups with increasing contact with the United States, from Mexicans with no familial connection to migration at one extreme, through US-born Mexican Americans at the other.     

Substance Use and Cumulative Exposure to American Society: Findings From Both Sides of the US–Mexico Border Region

Objectives. We investigated whether Mexican immigration to the United States exerts transnational effects on substance use in Mexico and the United States.Methods. We performed a cross-sectional survey of 2336 Mexican Americans and 2460 Mexicans in 3 Texas border metropolitan areas and their sister cities in Mexico (the US–Mexico Study on Alcohol and Related Conditions, 2011–2013). We collected prevalence and risk factors for alcohol and drug use; Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, alcohol-use disorders; and 2 symptoms (hazardous use and quit or control) of drug use disorder across a continuum of migration experiences in the Mexican and Mexican American populations.Results. Compared with Mexicans with no migrant experience, the adjusted odds ratios for this continuum of migration experiences ranged from 1.10 to 8.85 for 12-month drug use, 1.09 to 5.07 for 12-month alcohol use disorder, and 1.13 to 9.95 for 12-month drug-use disorder. Odds ratios increased with longer exposure to US society. These findings are consistent with those of 3 previous studies.Conclusions. People of Mexican origin have increased prevalence of substance use and disorders with cumulative exposure to US society.During the past 25 years, epidemiological research in the United States has consistently found that alcohol and drug use and disorders of use among Mexican immigrants and Mexican Americans tend to be associated with increasing immersion into US society.1–8 More recently, transnational effects of migration on substance use in both the United States and Mexico have become apparent. First, in a comparable Mexican population without any migration experience as a reference group, it was found that Mexican immigrants in the United States and US-born persons of Mexican origin exhibited increased risk of alcohol and drug use.9,10 Second, it was also shown that, in Mexico, substance use of return migrants and families of migrants was also affected by this immigration flow.11,12 These findings suggest a transnational pattern whereby Mexican immigrants increase their use of substances while in the United States by means of early age at immigration and years living in the United States,13–15 and transmit, directly and indirectly, substance use behaviors back into Mexico. This conceptualization is intriguing, but the data provided so far are limited to studies either in the United States or in Mexico. The only previous binational study9 collected data from a wide range of communities in Mexico and the United States and evidence with greater geographic detail is needed to corroborate and extend our understanding.The border regions of Mexico and the United States are particularly important as settings in which the cultures of the 2 countries come into contact and as transit points for migrants moving in both directions. The border region is also filled with contrasts. The US counties are much richer than the Mexican municipalities, but some of the US counties in the border area are among the poorest in the United States. At the same time, some of the Mexican border municipalities are among the richest when compared with national Mexican averages. Research in this region has documented the impact that US nativity, age at immigration, and years living in the United States have in increasing alcohol and drug use and disorders among those of Mexican ancestry living in the US borderland.8,16–18 On the Mexican side of the border, research generally documented higher prevalence rates for substance use and disorders of use when compared with cities off the border or against national averages.19Previous research nevertheless lacks a binational approach—with a common framework and risk factors. Our project, the first simultaneous study that includes the dynamic experiences of contemporary Mexican immigration on both sides of the border, has started to shed new insights on the alleged differences of alcohol and drug use and disorders of use in the US–Mexico border area.20,21 Our main hypothesis is that with early age of immigration, and increasing time and contact with the US culture, alcohol use, drug use, alcohol use disorders (AUDs) and symptoms of drug use disorder (DUD) will increase along a continuum of immigration experiences in this transnational population. Our main goal is to report the prevalence of, and risk factors for, the occurrence of alcohol use, drug use, AUD, and symptoms of DUD for this population of Mexican ancestry. A second goal is to put these new results in the context of previous findings and to examine the consistency of risk estimates for substance use across the full spectrum of the Mexican immigrant groups.