Hispanics have become the largest minority group in the United States. Compared to non-Hispanic whites, Hispanics are younger and less educated, with the concomitant problems of unemployment, poverty, lack of insurance and poor health care. In addition to the socioeconomic barriers other minorities face, a significant percentage of Hispanics speak poor or no English. In spite of the weight of Hispanics in the national population and the progress in a half-century of clinical psychopharmacology, we have no truly reliable data about treating mentally ill Hispanic-Americans with psychotropic medications.
For this brief review, I have taken a pragmatic approach, collecting information from heterogeneous sources, with very different degrees of reliability. The goal is not to give an erudite revision but to build a general picture that allows us to draw some conclusions regarding the pharmacotherapy of Hispanic-Americans suffering from depression and schizophrenia. I have focused on these disorders because we have some, albeit poor, information regarding the use of antidepressants and antipsychotics in Hispanics. However, for medication groups as important as mood stabilizers or anxiolytics, we have practically no information at all.Characteristics
Demographics. According to the U.S. Census 2000, Hispanics number 35.3 million or 12.5% of the U.S. population (Guzm'n, 2001). Their ranks grew 60% between 1990 and 2000, and three out of five Hispanics are foreign-born (Brodie et al., 2002). Hispanics are younger than the average American; 35.7% are less than 18 years old (versus 23.5% for non-Hispanic whites) (Therrien and Ramirez, 2001). They tend to concentrate in the central cities of metropolitan areas (46.4% versus 21.2% for non-Hispanic whites), live in larger households (30.6% in households of five or more people versus 11.8% for non-Hispanic whites), be less educated (57% are high school graduates versus 88.4% for non-Hispanic whites) and earn less money (in 1999, 23.3% of Hispanics and 49.3% of non-Hispanic whites earned $35,000 or more, and only 9.6% of Hispanics made $50,000 or more versus 27.4% of non-Hispanic whites) (Therrien and Ramirez, 2001).
Language. Only 28% of foreign-born Hispanics are English-dominant or bilingual versus 96% of U.S.-born Latinos. Forty-two percent of foreign-born and 8% of native-born Latinos report difficulty communicating with doctors or health care providers because of language barriers (Brodie et al., 2002).
Subgroups and heterogeneity. Mexicans are, by far, the largest Hispanic subgroup (60%) in the United States, with the other major subgroups (Puerto Ricans, Central Americans, South Americans and Cubans) in single digits (Guzm'n, 2001). This heterogeneity is a matter of contention, and some researchers prefer to identify their subjects according to specific subgroup. Although the issue is unsettled, I favor considering Hispanics as a single group for pharmacological purposes, because (among other reasons): a) the main Hispanic subgroups seem to share genes from the same ethnic pools, albeit in different proportions; and b) in spite of regional differences, Hispanics seem to be acceptably homogeneous, sharing habits, identities and attitudes. This last point is important, as the response to medications is determined not only by biological but also environmental and social factors (e.g., diet, toxin exposure and expectations).
Cultural traits. At least one--fatalism--needs to be mentioned. Among Hispanics, the differences in fatalism seem to be generational more than geographic. While over half of foreign-born Latinos believe they do not control their destiny, only one-quarter of U.S.-born Latinos feel this way (Brodie et al., 2002).
Health care. Hispanics are more likely to be uninsured and have less access to medical care. In 2002, 35% of Hispanics reported being uninsured (versus 14% of whites and 21% of African-Americans) (Brodie et al., 2002). Even when they are insured, Hispanics receive less medical services. For example, Hispanic Medicare beneficiaries have an odds ratio of 0.36 of receiving a hip replacement, as compared to non-Hispanic Medicare beneficiaries (Escalante et al., 2002). As this procedure is fully covered by Medicare, the finding suggests that underutilization of health services by Hispanics cannot be attributed to lack of health insurance alone.
Regarding mental health, Hispanics have both fewer visits and less chance of their mental problems being detected. For example, Latinos with fair and poor English proficiency reported approximately 22% fewer physician visits than non-Latinos, after adjusting for other determinants (Derose and Baker, 2000). In a review of 19,309 patients and 349 internists and family physicians, Hispanics and African-Americans were found to be at higher risk for non-detection of their mental health problems (Borowsky et al., 2000).
Psychiatric symptoms. The expression and reporting of psychiatric symptoms is partially determined by culture. I will not debate here the controversial issue of misdiagnosis in Hispanics. However, Hispanics with bipolar disorder are more likely to be labeled with schizophrenia, and Hispanics with depression (and probably anxiety) tend to somatize distress, reporting an excess of somatic and hypochondriacal features (Escobar, 1987; Mukherjee et al., 1983).Metabolic Issues
The cytochrome system. The only available data on Hispanics correspond to cytochrome P450 (CYP) 2D6 activity in Mexican-Americans, and show no significant differences with white Americans or African-Americans. Although their genotype for ADH2 and ALDH2 does not seem to be significantly different from whites, Mexican-Americans have shown a higher frequency for the mutant CYP 2E1, a cytochrome whose importance increases with alcohol(Drug information on alcohol) consumption (Konishi et al., 2003). This could play a role in the growing rate of alcoholic liver disease in Mexican-Americans.
Pharmacokinetics. Very few pharmacokinetic studies with psychotropics have been performed in Hispanics. No differences were found in the pharmacokinetics of nortriptyline(Drug information on nortriptyline) (Aventyl, Pamelor) between Hispanic and non-Hispanic subjects (Gaviria et al., 1986). The same is true for the biotransformation of haloperidol(Drug information on haloperidol) (Haldol): the curves of Hispanics, whites and African-Americans were close and differed from the Chinese (Jann et al., 1992).